diff --git a/src/interfaces/chain.cpp b/src/interfaces/chain.cpp
index 9d4e16f5f..dbf53ca9b 100644
--- a/src/interfaces/chain.cpp
+++ b/src/interfaces/chain.cpp
@@ -1,418 +1,431 @@
 // Copyright (c) 2018-2019 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <interfaces/chain.h>
 
 #include <chain.h>
 #include <chainparams.h>
 #include <interfaces/handler.h>
 #include <interfaces/wallet.h>
 #include <net.h>
 #include <net_processing.h>
 #include <node/coin.h>
 #include <node/context.h>
 #include <node/transaction.h>
 #include <policy/mempool.h>
 #include <policy/policy.h>
 #include <policy/settings.h>
 #include <primitives/block.h>
 #include <primitives/blockhash.h>
 #include <rpc/protocol.h>
 #include <rpc/server.h>
 #include <shutdown.h>
 #include <sync.h>
 #include <timedata.h>
 #include <txmempool.h>
 #include <ui_interface.h>
 #include <univalue.h>
 #include <util/system.h>
 #include <validation.h>
 #include <validationinterface.h>
 
 #include <utility>
 
 namespace interfaces {
 namespace {
 
+    bool FillBlock(const CBlockIndex *index, const FoundBlock &block,
+                   UniqueLock<RecursiveMutex> &lock) {
+        if (!index) {
+            return false;
+        }
+        if (block.m_hash) {
+            *block.m_hash = index->GetBlockHash();
+        }
+        if (block.m_height) {
+            *block.m_height = index->nHeight;
+        }
+        if (block.m_time) {
+            *block.m_time = index->GetBlockTime();
+        }
+        if (block.m_max_time) {
+            *block.m_max_time = index->GetBlockTimeMax();
+        }
+        if (block.m_mtp_time) {
+            *block.m_mtp_time = index->GetMedianTimePast();
+        }
+        if (block.m_data) {
+            REVERSE_LOCK(lock);
+            if (!ReadBlockFromDisk(*block.m_data, index,
+                                   Params().GetConsensus())) {
+                block.m_data->SetNull();
+            }
+        }
+        return true;
+    }
+
     class LockImpl : public Chain::Lock, public UniqueLock<RecursiveMutex> {
         Optional<int> getHeight() override {
             LockAssertion lock(::cs_main);
             int height = ::ChainActive().Height();
             if (height >= 0) {
                 return height;
             }
             return nullopt;
         }
         Optional<int> getBlockHeight(const BlockHash &hash) override {
             LockAssertion lock(::cs_main);
             CBlockIndex *block = LookupBlockIndex(hash);
             if (block && ::ChainActive().Contains(block)) {
                 return block->nHeight;
             }
             return nullopt;
         }
         BlockHash getBlockHash(int height) override {
             LockAssertion lock(::cs_main);
             CBlockIndex *block = ::ChainActive()[height];
             assert(block != nullptr);
             return block->GetBlockHash();
         }
         int64_t getBlockTime(int height) override {
             LockAssertion lock(::cs_main);
             CBlockIndex *block = ::ChainActive()[height];
             assert(block != nullptr);
             return block->GetBlockTime();
         }
         int64_t getBlockMedianTimePast(int height) override {
             LockAssertion lock(::cs_main);
             CBlockIndex *block = ::ChainActive()[height];
             assert(block != nullptr);
             return block->GetMedianTimePast();
         }
         bool haveBlockOnDisk(int height) override {
             LockAssertion lock(::cs_main);
             CBlockIndex *block = ::ChainActive()[height];
             return block && (block->nStatus.hasData() != 0) && block->nTx > 0;
         }
         Optional<int>
         findFirstBlockWithTimeAndHeight(int64_t time, int height,
                                         BlockHash *hash) override {
             LockAssertion lock(::cs_main);
             CBlockIndex *block =
                 ::ChainActive().FindEarliestAtLeast(time, height);
             if (block) {
                 if (hash) {
                     *hash = block->GetBlockHash();
                 }
                 return block->nHeight;
             }
             return nullopt;
         }
         Optional<int> findPruned(int start_height,
                                  Optional<int> stop_height) override {
             LockAssertion lock(::cs_main);
             if (::fPruneMode) {
                 CBlockIndex *block = stop_height ? ::ChainActive()[*stop_height]
                                                  : ::ChainActive().Tip();
                 while (block && block->nHeight >= start_height) {
                     if (block->nStatus.hasData() == 0) {
                         return block->nHeight;
                     }
                     block = block->pprev;
                 }
             }
             return nullopt;
         }
         Optional<int> findFork(const BlockHash &hash,
                                Optional<int> *height) override {
             LockAssertion lock(::cs_main);
             const CBlockIndex *block = LookupBlockIndex(hash);
             const CBlockIndex *fork =
                 block ? ::ChainActive().FindFork(block) : nullptr;
             if (height) {
                 if (block) {
                     *height = block->nHeight;
                 } else {
                     height->reset();
                 }
             }
             if (fork) {
                 return fork->nHeight;
             }
             return nullopt;
         }
         CBlockLocator getTipLocator() override {
             LockAssertion lock(::cs_main);
             return ::ChainActive().GetLocator();
         }
         Optional<int> findLocatorFork(const CBlockLocator &locator) override {
             LockAssertion lock(::cs_main);
             if (CBlockIndex *fork =
                     FindForkInGlobalIndex(::ChainActive(), locator)) {
                 return fork->nHeight;
             }
             return nullopt;
         }
         bool contextualCheckTransactionForCurrentBlock(
             const Consensus::Params &params, const CTransaction &tx,
             TxValidationState &state) override {
             LockAssertion lock(::cs_main);
             return ContextualCheckTransactionForCurrentBlock(params, tx, state);
         }
 
         using UniqueLock::UniqueLock;
     }; // namespace interfaces
 
     class NotificationsProxy : public CValidationInterface {
     public:
         explicit NotificationsProxy(
             std::shared_ptr<Chain::Notifications> notifications)
             : m_notifications(std::move(notifications)) {}
         virtual ~NotificationsProxy() = default;
         void TransactionAddedToMempool(const CTransactionRef &tx) override {
             m_notifications->TransactionAddedToMempool(tx);
         }
         void TransactionRemovedFromMempool(const CTransactionRef &tx) override {
             m_notifications->TransactionRemovedFromMempool(tx);
         }
         void BlockConnected(
             const std::shared_ptr<const CBlock> &block,
             const CBlockIndex *index,
             const std::vector<CTransactionRef> &tx_conflicted) override {
             m_notifications->BlockConnected(*block, tx_conflicted,
                                             index->nHeight);
         }
         void BlockDisconnected(const std::shared_ptr<const CBlock> &block,
                                const CBlockIndex *index) override {
             m_notifications->BlockDisconnected(*block, index->nHeight);
         }
         void UpdatedBlockTip(const CBlockIndex *index,
                              const CBlockIndex *fork_index,
                              bool is_ibd) override {
             m_notifications->UpdatedBlockTip();
         }
         void ChainStateFlushed(const CBlockLocator &locator) override {
             m_notifications->ChainStateFlushed(locator);
         }
         std::shared_ptr<Chain::Notifications> m_notifications;
     };
 
     class NotificationsHandlerImpl : public Handler {
     public:
         explicit NotificationsHandlerImpl(
             std::shared_ptr<Chain::Notifications> notifications)
             : m_proxy(std::make_shared<NotificationsProxy>(
                   std::move(notifications))) {
             RegisterSharedValidationInterface(m_proxy);
         }
         ~NotificationsHandlerImpl() override { disconnect(); }
         void disconnect() override {
             if (m_proxy) {
                 UnregisterSharedValidationInterface(m_proxy);
                 m_proxy.reset();
             }
         }
         std::shared_ptr<NotificationsProxy> m_proxy;
     };
 
     class RpcHandlerImpl : public Handler {
     public:
         explicit RpcHandlerImpl(const CRPCCommand &command)
             : m_command(command), m_wrapped_command(&command) {
             m_command.actor = [this](Config &config,
                                      const JSONRPCRequest &request,
                                      UniValue &result, bool last_handler) {
                 if (!m_wrapped_command) {
                     return false;
                 }
                 try {
                     return m_wrapped_command->actor(config, request, result,
                                                     last_handler);
                 } catch (const UniValue &e) {
                     // If this is not the last handler and a wallet not found
                     // exception was thrown, return false so the next handler
                     // can try to handle the request. Otherwise, reraise the
                     // exception.
                     if (!last_handler) {
                         const UniValue &code = e["code"];
                         if (code.isNum() &&
                             code.get_int() == RPC_WALLET_NOT_FOUND) {
                             return false;
                         }
                     }
                     throw;
                 }
             };
             ::tableRPC.appendCommand(m_command.name, &m_command);
         }
 
         void disconnect() override final {
             if (m_wrapped_command) {
                 m_wrapped_command = nullptr;
                 ::tableRPC.removeCommand(m_command.name, &m_command);
             }
         }
 
         ~RpcHandlerImpl() override { disconnect(); }
 
         CRPCCommand m_command;
         const CRPCCommand *m_wrapped_command;
     };
 
     class ChainImpl : public Chain {
     public:
         explicit ChainImpl(NodeContext &node, const CChainParams &params)
             : m_node(node), m_params(params) {}
         std::unique_ptr<Chain::Lock> lock(bool try_lock) override {
             auto lock = std::make_unique<LockImpl>(
                 ::cs_main, "cs_main", __FILE__, __LINE__, try_lock);
             if (try_lock && lock && !*lock) {
                 return {};
             }
             // Temporary to avoid CWG 1579
             std::unique_ptr<Chain::Lock> result = std::move(lock);
             return result;
         }
-        bool findBlock(const BlockHash &hash, CBlock *block, int64_t *time,
-                       int64_t *time_max) override {
-            CBlockIndex *index;
-            {
-                LOCK(cs_main);
-                index = LookupBlockIndex(hash);
-                if (!index) {
-                    return false;
-                }
-                if (time) {
-                    *time = index->GetBlockTime();
-                }
-                if (time_max) {
-                    *time_max = index->GetBlockTimeMax();
-                }
-            }
-            if (block &&
-                !ReadBlockFromDisk(*block, index, Params().GetConsensus())) {
-                block->SetNull();
-            }
-            return true;
+        bool findBlock(const BlockHash &hash,
+                       const FoundBlock &block) override {
+            WAIT_LOCK(cs_main, lock);
+            return FillBlock(LookupBlockIndex(hash), block, lock);
         }
         void findCoins(std::map<COutPoint, Coin> &coins) override {
             return FindCoins(coins);
         }
         double guessVerificationProgress(const BlockHash &block_hash) override {
             LOCK(cs_main);
             return GuessVerificationProgress(Params().TxData(),
                                              LookupBlockIndex(block_hash));
         }
         bool hasDescendantsInMempool(const TxId &txid) override {
             LOCK(::g_mempool.cs);
             auto it = ::g_mempool.GetIter(txid);
             return it && (*it)->GetCountWithDescendants() > 1;
         }
         bool broadcastTransaction(const Config &config,
                                   const CTransactionRef &tx,
                                   std::string &err_string,
                                   const Amount &max_tx_fee,
                                   bool relay) override {
             const TransactionError err = BroadcastTransaction(
                 m_node, config, tx, err_string, max_tx_fee, relay,
                 /*wait_callback*/ false);
             // Chain clients only care about failures to accept the tx to the
             // mempool. Disregard non-mempool related failures. Note: this will
             // need to be updated if BroadcastTransactions() is updated to
             // return other non-mempool failures that Chain clients do not need
             // to know about.
             return err == TransactionError::OK;
         }
         void getTransactionAncestry(const TxId &txid, size_t &ancestors,
                                     size_t &descendants) override {
             ::g_mempool.GetTransactionAncestry(txid, ancestors, descendants);
         }
         void getPackageLimits(size_t &limit_ancestor_count,
                               size_t &limit_descendant_count) override {
             limit_ancestor_count = size_t(
                 std::max<int64_t>(1, gArgs.GetArg("-limitancestorcount",
                                                   DEFAULT_ANCESTOR_LIMIT)));
             limit_descendant_count = size_t(
                 std::max<int64_t>(1, gArgs.GetArg("-limitdescendantcount",
                                                   DEFAULT_DESCENDANT_LIMIT)));
         }
         bool checkChainLimits(const CTransactionRef &tx) override {
             LockPoints lp;
             CTxMemPoolEntry entry(tx, Amount(), 0, 0, false, 0, lp);
             CTxMemPool::setEntries ancestors;
             auto limit_ancestor_count =
                 gArgs.GetArg("-limitancestorcount", DEFAULT_ANCESTOR_LIMIT);
             auto limit_ancestor_size =
                 gArgs.GetArg("-limitancestorsize",
                              DEFAULT_ANCESTOR_SIZE_LIMIT) *
                 1000;
             auto limit_descendant_count =
                 gArgs.GetArg("-limitdescendantcount", DEFAULT_DESCENDANT_LIMIT);
             auto limit_descendant_size =
                 gArgs.GetArg("-limitdescendantsize",
                              DEFAULT_DESCENDANT_SIZE_LIMIT) *
                 1000;
             std::string unused_error_string;
             LOCK(::g_mempool.cs);
             return ::g_mempool.CalculateMemPoolAncestors(
                 entry, ancestors, limit_ancestor_count, limit_ancestor_size,
                 limit_descendant_count, limit_descendant_size,
                 unused_error_string);
         }
         CFeeRate estimateFee() const override {
             return ::g_mempool.estimateFee();
         }
         CFeeRate relayMinFee() override { return ::minRelayTxFee; }
         CFeeRate relayDustFee() override { return ::dustRelayFee; }
         bool havePruned() override {
             LOCK(cs_main);
             return ::fHavePruned;
         }
         bool isReadyToBroadcast() override {
             return !::fImporting && !::fReindex && !isInitialBlockDownload();
         }
         bool isInitialBlockDownload() override {
             return ::ChainstateActive().IsInitialBlockDownload();
         }
         bool shutdownRequested() override { return ShutdownRequested(); }
         int64_t getAdjustedTime() override { return GetAdjustedTime(); }
         void initMessage(const std::string &message) override {
             ::uiInterface.InitMessage(message);
         }
         void initWarning(const std::string &message) override {
             InitWarning(message);
         }
         void initError(const std::string &message) override {
             InitError(message);
         }
         void showProgress(const std::string &title, int progress,
                           bool resume_possible) override {
             ::uiInterface.ShowProgress(title, progress, resume_possible);
         }
         std::unique_ptr<Handler> handleNotifications(
             std::shared_ptr<Notifications> notifications) override {
             return std::make_unique<NotificationsHandlerImpl>(
                 std::move(notifications));
         }
         void
         waitForNotificationsIfTipChanged(const BlockHash &old_tip) override {
             if (!old_tip.IsNull()) {
                 LOCK(::cs_main);
                 if (old_tip == ::ChainActive().Tip()->GetBlockHash()) {
                     return;
                 }
             }
             SyncWithValidationInterfaceQueue();
         }
 
         std::unique_ptr<Handler>
         handleRpc(const CRPCCommand &command) override {
             return std::make_unique<RpcHandlerImpl>(command);
         }
         bool rpcEnableDeprecated(const std::string &method) override {
             return IsDeprecatedRPCEnabled(gArgs, method);
         }
         void rpcRunLater(const std::string &name, std::function<void()> fn,
                          int64_t seconds) override {
             RPCRunLater(name, std::move(fn), seconds);
         }
         int rpcSerializationFlags() override { return RPCSerializationFlags(); }
         void requestMempoolTransactions(Notifications &notifications) override {
             LOCK2(::cs_main, ::g_mempool.cs);
             for (const CTxMemPoolEntry &entry : ::g_mempool.mapTx) {
                 notifications.TransactionAddedToMempool(entry.GetSharedTx());
             }
         }
         NodeContext &m_node;
         const CChainParams &m_params;
     };
 
 } // namespace
 
 std::unique_ptr<Chain> MakeChain(NodeContext &node,
                                  const CChainParams &params) {
     return std::make_unique<ChainImpl>(node, params);
 }
 
 } // namespace interfaces
diff --git a/src/interfaces/chain.h b/src/interfaces/chain.h
index 8c8e0774a..1a56ac6fa 100644
--- a/src/interfaces/chain.h
+++ b/src/interfaces/chain.h
@@ -1,313 +1,346 @@
 // Copyright (c) 2018-2019 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #ifndef BITCOIN_INTERFACES_CHAIN_H
 #define BITCOIN_INTERFACES_CHAIN_H
 
 #include <optional.h>
 #include <primitives/transaction.h>
 #include <primitives/txid.h>
 
 #include <cstddef>
 #include <cstdint>
 #include <memory>
 #include <string>
 #include <vector>
 
 class CBlock;
 class CChainParams;
 class Coin;
 class Config;
 class CRPCCommand;
 class CScheduler;
 class TxValidationState;
 
 struct BlockHash;
 struct CBlockLocator;
 struct NodeContext;
 
 namespace Consensus {
 struct Params;
 }
 
 namespace interfaces {
 
 class Handler;
 class Wallet;
 
+//! Helper for findBlock to selectively return pieces of block data.
+class FoundBlock {
+public:
+    FoundBlock &hash(BlockHash &hash) {
+        m_hash = &hash;
+        return *this;
+    }
+    FoundBlock &height(int &height) {
+        m_height = &height;
+        return *this;
+    }
+    FoundBlock &time(int64_t &time) {
+        m_time = &time;
+        return *this;
+    }
+    FoundBlock &maxTime(int64_t &max_time) {
+        m_max_time = &max_time;
+        return *this;
+    }
+    FoundBlock &mtpTime(int64_t &mtp_time) {
+        m_mtp_time = &mtp_time;
+        return *this;
+    }
+    //! Read block data from disk. If the block exists but doesn't have data
+    //! (for example due to pruning), the CBlock variable will be set to null.
+    FoundBlock &data(CBlock &data) {
+        m_data = &data;
+        return *this;
+    }
+
+    BlockHash *m_hash = nullptr;
+    int *m_height = nullptr;
+    int64_t *m_time = nullptr;
+    int64_t *m_max_time = nullptr;
+    int64_t *m_mtp_time = nullptr;
+    CBlock *m_data = nullptr;
+};
+
 //! Interface giving clients (wallet processes, maybe other analysis tools in
 //! the future) ability to access to the chain state, receive notifications,
 //! estimate fees, and submit transactions.
 //!
 //! TODO: Current chain methods are too low level, exposing too much of the
 //! internal workings of the bitcoin node, and not being very convenient to use.
 //! Chain methods should be cleaned up and simplified over time. Examples:
 //!
 //! * The Chain::lock() method, which lets clients delay chain tip updates
 //!   should be removed when clients are able to respond to updates
 //!   asynchronously
 //!   (https://github.com/bitcoin/bitcoin/pull/10973#issuecomment-380101269).
 //!
 //! * The initMessage() and showProgress() methods which the wallet uses to send
 //!   notifications to the GUI should go away when GUI and wallet can directly
 //!   communicate with each other without going through the node
 //!   (https://github.com/bitcoin/bitcoin/pull/15288#discussion_r253321096).
 //!
 //! * The handleRpc, registerRpcs, rpcEnableDeprecated methods and other RPC
 //!   methods can go away if wallets listen for HTTP requests on their own
 //!   ports instead of registering to handle requests on the node HTTP port.
 class Chain {
 public:
     virtual ~Chain() {}
 
     //! Interface for querying locked chain state, used by legacy code that
     //! assumes state won't change between calls. New code should avoid using
     //! the Lock interface and instead call higher-level Chain methods
     //! that return more information so the chain doesn't need to stay locked
     //! between calls.
     class Lock {
     public:
         virtual ~Lock() {}
 
         //! Get current chain height, not including genesis block (returns 0 if
         //! chain only contains genesis block, nullopt if chain does not contain
         //! any blocks).
         virtual Optional<int> getHeight() = 0;
 
         //! Get block height above genesis block. Returns 0 for genesis block,
         //! 1 for following block, and so on. Returns nullopt for a block not
         //! included in the current chain.
         virtual Optional<int> getBlockHeight(const BlockHash &hash) = 0;
 
         //! Get block hash. Height must be valid or this function will abort.
         virtual BlockHash getBlockHash(int height) = 0;
 
         //! Get block time. Height must be valid or this function will abort.
         virtual int64_t getBlockTime(int height) = 0;
 
         //! Get block median time past. Height must be valid or this function
         //! will abort.
         virtual int64_t getBlockMedianTimePast(int height) = 0;
 
         //! Check that the block is available on disk (i.e. has not been
         //! pruned), and contains transactions.
         virtual bool haveBlockOnDisk(int height) = 0;
 
         //! Return height of the first block in the chain with timestamp equal
         //! or greater than the given time and height equal or greater than the
         //! given height, or nullopt if there is no block with a high enough
         //! timestamp and height. Also return the block hash as an optional
         //! output parameter (to avoid the cost of a second lookup in case this
         //! information is needed.)
         virtual Optional<int>
         findFirstBlockWithTimeAndHeight(int64_t time, int height,
                                         BlockHash *hash) = 0;
 
         //! Return height of last block in the specified range which is pruned,
         //! or nullopt if no block in the range is pruned. Range is inclusive.
         virtual Optional<int>
         findPruned(int start_height = 0,
                    Optional<int> stop_height = nullopt) = 0;
 
         //! Return height of the highest block on the chain that is an ancestor
         //! of the specified block, or nullopt if no common ancestor is found.
         //! Also return the height of the specified block as an optional output
         //! parameter (to avoid the cost of a second hash lookup in case this
         //! information is desired).
         virtual Optional<int> findFork(const BlockHash &hash,
                                        Optional<int> *height) = 0;
 
         //! Get locator for the current chain tip.
         virtual CBlockLocator getTipLocator() = 0;
 
         //! Return height of the latest block common to locator and chain, which
         //! is guaranteed to be an ancestor of the block used to create the
         //! locator.
         virtual Optional<int> findLocatorFork(const CBlockLocator &locator) = 0;
 
         //! Check if transaction will be final given chain height current time.
         virtual bool contextualCheckTransactionForCurrentBlock(
             const Consensus::Params &params, const CTransaction &tx,
             TxValidationState &state) = 0;
     };
 
     //! Return Lock interface. Chain is locked when this is called, and
     //! unlocked when the returned interface is freed.
     virtual std::unique_ptr<Lock> lock(bool try_lock = false) = 0;
 
     //! Return whether node has the block and optionally return block metadata
     //! or contents.
-    //!
-    //! If a block pointer is provided to retrieve the block contents, and the
-    //! block exists but doesn't have data (for example due to pruning), the
-    //! block will be empty and all fields set to null.
-    virtual bool findBlock(const BlockHash &hash, CBlock *block = nullptr,
-                           int64_t *time = nullptr,
-                           int64_t *max_time = nullptr) = 0;
+    virtual bool findBlock(const BlockHash &hash,
+                           const FoundBlock &block = {}) = 0;
 
     //! Look up unspent output information. Returns coins in the mempool and in
     //! the current chain UTXO set. Iterates through all the keys in the map and
     //! populates the values.
     virtual void findCoins(std::map<COutPoint, Coin> &coins) = 0;
 
     //! Estimate fraction of total transactions verified if blocks up to
     //! the specified block hash are verified.
     virtual double guessVerificationProgress(const BlockHash &block_hash) = 0;
 
     //! Check if transaction has descendants in mempool.
     virtual bool hasDescendantsInMempool(const TxId &txid) = 0;
 
     //! Transaction is added to memory pool, if the transaction fee is below the
     //! amount specified by max_tx_fee, and broadcast to all peers if relay is
     //! set to true. Return false if the transaction could not be added due to
     //! the fee or for another reason.
     virtual bool broadcastTransaction(const Config &config,
                                       const CTransactionRef &tx,
                                       std::string &err_string,
                                       const Amount &max_tx_fee, bool relay) = 0;
 
     //! Calculate mempool ancestor and descendant counts for the given
     //! transaction.
     virtual void getTransactionAncestry(const TxId &txid, size_t &ancestors,
                                         size_t &descendants) = 0;
 
     //! Get the node's package limits.
     //! Currently only returns the ancestor and descendant count limits, but
     //! could be enhanced to return more policy settings.
     virtual void getPackageLimits(size_t &limit_ancestor_count,
                                   size_t &limit_descendant_count) = 0;
 
     //! Check if transaction will pass the mempool's chain limits.
     virtual bool checkChainLimits(const CTransactionRef &tx) = 0;
 
     //! Estimate fee
     virtual CFeeRate estimateFee() const = 0;
 
     //! Relay current minimum fee (from -minrelaytxfee settings).
     virtual CFeeRate relayMinFee() = 0;
 
     //! Relay dust fee setting (-dustrelayfee), reflecting lowest rate it's
     //! economical to spend.
     virtual CFeeRate relayDustFee() = 0;
 
     //! Check if any block has been pruned.
     virtual bool havePruned() = 0;
 
     //! Check if the node is ready to broadcast transactions.
     virtual bool isReadyToBroadcast() = 0;
 
     //! Check if in IBD.
     virtual bool isInitialBlockDownload() = 0;
 
     //! Check if shutdown requested.
     virtual bool shutdownRequested() = 0;
 
     //! Get adjusted time.
     virtual int64_t getAdjustedTime() = 0;
 
     //! Send init message.
     virtual void initMessage(const std::string &message) = 0;
 
     //! Send init warning.
     virtual void initWarning(const std::string &message) = 0;
 
     //! Send init error.
     virtual void initError(const std::string &message) = 0;
 
     //! Send progress indicator.
     virtual void showProgress(const std::string &title, int progress,
                               bool resume_possible) = 0;
 
     //! Chain notifications.
     class Notifications {
     public:
         virtual ~Notifications() {}
         virtual void TransactionAddedToMempool(const CTransactionRef &tx) {}
         virtual void TransactionRemovedFromMempool(const CTransactionRef &ptx) {
         }
         virtual void
         BlockConnected(const CBlock &block,
                        const std::vector<CTransactionRef> &tx_conflicted,
                        int height) {}
         virtual void BlockDisconnected(const CBlock &block, int height) {}
         virtual void UpdatedBlockTip() {}
         virtual void ChainStateFlushed(const CBlockLocator &locator) {}
     };
 
     //! Register handler for notifications.
     virtual std::unique_ptr<Handler>
     handleNotifications(std::shared_ptr<Notifications> notifications) = 0;
 
     //! Wait for pending notifications to be processed unless block hash points
     //! to the current chain tip.
     virtual void waitForNotificationsIfTipChanged(const BlockHash &old_tip) = 0;
 
     //! Register handler for RPC. Command is not copied, so reference
     //! needs to remain valid until Handler is disconnected.
     virtual std::unique_ptr<Handler> handleRpc(const CRPCCommand &command) = 0;
 
     //! Check if deprecated RPC is enabled.
     virtual bool rpcEnableDeprecated(const std::string &method) = 0;
 
     //! Run function after given number of seconds. Cancel any previous calls
     //! with same name.
     virtual void rpcRunLater(const std::string &name, std::function<void()> fn,
                              int64_t seconds) = 0;
 
     //! Current RPC serialization flags.
     virtual int rpcSerializationFlags() = 0;
 
     //! Synchronously send TransactionAddedToMempool notifications about all
     //! current mempool transactions to the specified handler and return after
     //! the last one is sent. These notifications aren't coordinated with async
     //! notifications sent by handleNotifications, so out of date async
     //! notifications from handleNotifications can arrive during and after
     //! synchronous notifications from requestMempoolTransactions. Clients need
     //! to be prepared to handle this by ignoring notifications about unknown
     //! removed transactions and already added new transactions.
     virtual void requestMempoolTransactions(Notifications &notifications) = 0;
 };
 
 //! Interface to let node manage chain clients (wallets, or maybe tools for
 //! monitoring and analysis in the future).
 class ChainClient {
 public:
     virtual ~ChainClient() {}
 
     //! Register rpcs.
     virtual void registerRpcs() = 0;
 
     //! Check for errors before loading.
     virtual bool verify(const CChainParams &chainParams) = 0;
 
     //! Load saved state.
     virtual bool load(const CChainParams &chainParams) = 0;
 
     //! Start client execution and provide a scheduler.
     virtual void start(CScheduler &scheduler) = 0;
 
     //! Save state to disk.
     virtual void flush() = 0;
 
     //! Shut down client.
     virtual void stop() = 0;
 };
 
 //! Return implementation of Chain interface.
 std::unique_ptr<Chain> MakeChain(NodeContext &node, const CChainParams &params);
 
 //! Return implementation of ChainClient interface for a wallet client. This
 //! function will be undefined in builds where ENABLE_WALLET is false.
 //!
 //! Currently, wallets are the only chain clients. But in the future, other
 //! types of chain clients could be added, such as tools for monitoring,
 //! analysis, or fee estimation. These clients need to expose their own
 //! MakeXXXClient functions returning their implementations of the ChainClient
 //! interface.
 std::unique_ptr<ChainClient>
 MakeWalletClient(Chain &chain, std::vector<std::string> wallet_filenames);
 
 } // namespace interfaces
 
 #endif // BITCOIN_INTERFACES_CHAIN_H
diff --git a/src/sync.h b/src/sync.h
index b044294bb..ed8550aad 100644
--- a/src/sync.h
+++ b/src/sync.h
@@ -1,361 +1,361 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
 // Copyright (c) 2009-2016 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #ifndef BITCOIN_SYNC_H
 #define BITCOIN_SYNC_H
 
 #include <threadsafety.h>
 #include <util/macros.h>
 
 #include <condition_variable>
 #include <mutex>
 #include <thread>
 
 /////////////////////////////////////////////////
 //                                             //
 // THE SIMPLE DEFINITION, EXCLUDING DEBUG CODE //
 //                                             //
 /////////////////////////////////////////////////
 
 /*
 RecursiveMutex mutex;
     std::recursive_mutex mutex;
 
 LOCK(mutex);
     std::unique_lock<std::recursive_mutex> criticalblock(mutex);
 
 LOCK2(mutex1, mutex2);
     std::unique_lock<std::recursive_mutex> criticalblock1(mutex1);
     std::unique_lock<std::recursive_mutex> criticalblock2(mutex2);
 
 TRY_LOCK(mutex, name);
     std::unique_lock<std::recursive_mutex> name(mutex, std::try_to_lock_t);
 
 ENTER_CRITICAL_SECTION(mutex); // no RAII
     mutex.lock();
 
 LEAVE_CRITICAL_SECTION(mutex); // no RAII
     mutex.unlock();
  */
 
 ///////////////////////////////
 //                           //
 // THE ACTUAL IMPLEMENTATION //
 //                           //
 ///////////////////////////////
 
 #ifdef DEBUG_LOCKORDER
 void EnterCritical(const char *pszName, const char *pszFile, int nLine,
                    void *cs, bool fTry = false);
 void LeaveCritical();
 void CheckLastCritical(void *cs, std::string &lockname, const char *guardname,
                        const char *file, int line);
 std::string LocksHeld();
 void AssertLockHeldInternal(const char *pszName, const char *pszFile, int nLine,
                             void *cs) ASSERT_EXCLUSIVE_LOCK(cs);
 void AssertLockNotHeldInternal(const char *pszName, const char *pszFile,
                                int nLine, void *cs);
 void DeleteLock(void *cs);
 
 /**
  * Call abort() if a potential lock order deadlock bug is detected, instead of
  * just logging information and throwing a logic_error. Defaults to true, and
  * set to false in DEBUG_LOCKORDER unit tests.
  */
 extern bool g_debug_lockorder_abort;
 #else
 static inline void EnterCritical(const char *pszName, const char *pszFile,
                                  int nLine, void *cs, bool fTry = false) {}
 static inline void LeaveCritical() {}
 static inline void CheckLastCritical(void *cs, std::string &lockname,
                                      const char *guardname, const char *file,
                                      int line) {}
 static inline void AssertLockHeldInternal(const char *pszName,
                                           const char *pszFile, int nLine,
                                           void *cs) ASSERT_EXCLUSIVE_LOCK(cs) {}
 static inline void AssertLockNotHeldInternal(const char *pszName,
                                              const char *pszFile, int nLine,
                                              void *cs) {}
 static inline void DeleteLock(void *cs) {}
 #endif
 #define AssertLockHeld(cs) AssertLockHeldInternal(#cs, __FILE__, __LINE__, &cs)
 #define AssertLockNotHeld(cs)                                                  \
     AssertLockNotHeldInternal(#cs, __FILE__, __LINE__, &cs)
 
 /**
  * Template mixin that adds -Wthread-safety locking annotations and lock order
  * checking to a subset of the mutex API.
  */
 template <typename PARENT> class LOCKABLE AnnotatedMixin : public PARENT {
 public:
     ~AnnotatedMixin() { DeleteLock((void *)this); }
 
     void lock() EXCLUSIVE_LOCK_FUNCTION() { PARENT::lock(); }
 
     void unlock() UNLOCK_FUNCTION() { PARENT::unlock(); }
 
     bool try_lock() EXCLUSIVE_TRYLOCK_FUNCTION(true) {
         return PARENT::try_lock();
     }
 
     using UniqueLock = std::unique_lock<PARENT>;
 };
 
 /**
  * Wrapped mutex: supports recursive locking, but no waiting
  * TODO: We should move away from using the recursive lock by default.
  */
 using RecursiveMutex = AnnotatedMixin<std::recursive_mutex>;
 
 /** Wrapped mutex: supports waiting but not recursive locking */
 typedef AnnotatedMixin<std::mutex> Mutex;
 
 #ifdef DEBUG_LOCKCONTENTION
 void PrintLockContention(const char *pszName, const char *pszFile, int nLine);
 #endif
 
 /** Wrapper around std::unique_lock style lock for Mutex. */
 template <typename Mutex, typename Base = typename Mutex::UniqueLock>
 class SCOPED_LOCKABLE UniqueLock : public Base {
 private:
     void Enter(const char *pszName, const char *pszFile, int nLine) {
         EnterCritical(pszName, pszFile, nLine, (void *)(Base::mutex()));
 #ifdef DEBUG_LOCKCONTENTION
         if (!Base::try_lock()) {
             PrintLockContention(pszName, pszFile, nLine);
 #endif
             Base::lock();
 #ifdef DEBUG_LOCKCONTENTION
         }
 #endif
     }
 
     bool TryEnter(const char *pszName, const char *pszFile, int nLine) {
         EnterCritical(pszName, pszFile, nLine, (void *)(Base::mutex()), true);
         Base::try_lock();
         if (!Base::owns_lock()) {
             LeaveCritical();
         }
         return Base::owns_lock();
     }
 
 public:
     UniqueLock(Mutex &mutexIn, const char *pszName, const char *pszFile,
                int nLine, bool fTry = false) EXCLUSIVE_LOCK_FUNCTION(mutexIn)
         : Base(mutexIn, std::defer_lock) {
         if (fTry) {
             TryEnter(pszName, pszFile, nLine);
         } else {
             Enter(pszName, pszFile, nLine);
         }
     }
 
     UniqueLock(Mutex *pmutexIn, const char *pszName, const char *pszFile,
                int nLine, bool fTry = false) EXCLUSIVE_LOCK_FUNCTION(pmutexIn) {
         if (!pmutexIn) {
             return;
         }
 
         *static_cast<Base *>(this) = Base(*pmutexIn, std::defer_lock);
         if (fTry) {
             TryEnter(pszName, pszFile, nLine);
         } else {
             Enter(pszName, pszFile, nLine);
         }
     }
 
     ~UniqueLock() UNLOCK_FUNCTION() {
         if (Base::owns_lock()) {
             LeaveCritical();
         }
     }
 
     operator bool() { return Base::owns_lock(); }
 
 protected:
     // needed for reverse_lock
     UniqueLock() {}
 
 public:
     /**
      * An RAII-style reverse lock. Unlocks on construction and locks on
      * destruction.
      */
     class reverse_lock {
     public:
         explicit reverse_lock(UniqueLock &_lock, const char *_guardname,
                               const char *_file, int _line)
             : lock(_lock), file(_file), line(_line) {
             CheckLastCritical((void *)lock.mutex(), lockname, _guardname, _file,
                               _line);
             lock.unlock();
             LeaveCritical();
             lock.swap(templock);
         }
 
         ~reverse_lock() {
             templock.swap(lock);
             EnterCritical(lockname.c_str(), file.c_str(), line,
                           (void *)lock.mutex());
             lock.lock();
         }
 
     private:
         reverse_lock(reverse_lock const &);
         reverse_lock &operator=(reverse_lock const &);
 
         UniqueLock &lock;
         UniqueLock templock;
         std::string lockname;
         const std::string file;
         const int line;
     };
     friend class reverse_lock;
 };
 
 #define REVERSE_LOCK(g)                                                        \
-    decltype(g)::reverse_lock PASTE2(revlock, __COUNTER__)(g, #g, __FILE__,    \
-                                                           __LINE__)
+    typename std::decay<decltype(g)>::type::reverse_lock PASTE2(               \
+        revlock, __COUNTER__)(g, #g, __FILE__, __LINE__)
 
 template <typename MutexArg>
 using DebugLock = UniqueLock<typename std::remove_reference<
     typename std::remove_pointer<MutexArg>::type>::type>;
 
 #define LOCK(cs)                                                               \
     DebugLock<decltype(cs)> PASTE2(criticalblock,                              \
                                    __COUNTER__)(cs, #cs, __FILE__, __LINE__)
 #define LOCK2(cs1, cs2)                                                        \
     DebugLock<decltype(cs1)> criticalblock1(cs1, #cs1, __FILE__, __LINE__);    \
     DebugLock<decltype(cs2)> criticalblock2(cs2, #cs2, __FILE__, __LINE__);
 #define TRY_LOCK(cs, name)                                                     \
     DebugLock<decltype(cs)> name(cs, #cs, __FILE__, __LINE__, true)
 #define WAIT_LOCK(cs, name)                                                    \
     DebugLock<decltype(cs)> name(cs, #cs, __FILE__, __LINE__)
 
 #define ENTER_CRITICAL_SECTION(cs)                                             \
     {                                                                          \
         EnterCritical(#cs, __FILE__, __LINE__, (void *)(&cs));                 \
         (cs).lock();                                                           \
     }
 
 #define LEAVE_CRITICAL_SECTION(cs)                                             \
     {                                                                          \
         (cs).unlock();                                                         \
         LeaveCritical();                                                       \
     }
 
 //! Run code while locking a mutex.
 //!
 //! Examples:
 //!
 //!   WITH_LOCK(cs, shared_val = shared_val + 1);
 //!
 //!   int val = WITH_LOCK(cs, return shared_val);
 //!
 #define WITH_LOCK(cs, code)                                                    \
     [&] {                                                                      \
         LOCK(cs);                                                              \
         code;                                                                  \
     }()
 
 class CSemaphore {
 private:
     std::condition_variable condition;
     std::mutex mutex;
     int value;
 
 public:
     explicit CSemaphore(int init) : value(init) {}
 
     void wait() {
         std::unique_lock<std::mutex> lock(mutex);
         condition.wait(lock, [&]() { return value >= 1; });
         value--;
     }
 
     bool try_wait() {
         std::lock_guard<std::mutex> lock(mutex);
         if (value < 1) {
             return false;
         }
         value--;
         return true;
     }
 
     void post() {
         {
             std::lock_guard<std::mutex> lock(mutex);
             value++;
         }
         condition.notify_one();
     }
 };
 
 /** RAII-style semaphore lock */
 class CSemaphoreGrant {
 private:
     CSemaphore *sem;
     bool fHaveGrant;
 
 public:
     void Acquire() {
         if (fHaveGrant) {
             return;
         }
         sem->wait();
         fHaveGrant = true;
     }
 
     void Release() {
         if (!fHaveGrant) {
             return;
         }
         sem->post();
         fHaveGrant = false;
     }
 
     bool TryAcquire() {
         if (!fHaveGrant && sem->try_wait()) {
             fHaveGrant = true;
         }
         return fHaveGrant;
     }
 
     void MoveTo(CSemaphoreGrant &grant) {
         grant.Release();
         grant.sem = sem;
         grant.fHaveGrant = fHaveGrant;
         fHaveGrant = false;
     }
 
     CSemaphoreGrant() : sem(nullptr), fHaveGrant(false) {}
 
     explicit CSemaphoreGrant(CSemaphore &sema, bool fTry = false)
         : sem(&sema), fHaveGrant(false) {
         if (fTry) {
             TryAcquire();
         } else {
             Acquire();
         }
     }
 
     ~CSemaphoreGrant() { Release(); }
 
     operator bool() const { return fHaveGrant; }
 };
 
 // Utility class for indicating to compiler thread analysis that a mutex is
 // locked (when it couldn't be determined otherwise).
 struct SCOPED_LOCKABLE LockAssertion {
     template <typename Mutex>
     explicit LockAssertion(Mutex &mutex) EXCLUSIVE_LOCK_FUNCTION(mutex) {
 #ifdef DEBUG_LOCKORDER
         AssertLockHeld(mutex);
 #endif
     }
     ~LockAssertion() UNLOCK_FUNCTION() {}
 };
 
 #endif // BITCOIN_SYNC_H
diff --git a/src/test/CMakeLists.txt b/src/test/CMakeLists.txt
index 36a239c95..42c3f85ec 100644
--- a/src/test/CMakeLists.txt
+++ b/src/test/CMakeLists.txt
@@ -1,247 +1,248 @@
 # Copyright (c) 2018 The Bitcoin developers
 
 project(bitcoin-test)
 
 # Process json files.
 file(MAKE_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/data")
 
 function(gen_json_header NAME)
 	set(HEADERS "")
 	foreach(f ${ARGN})
 		set(h "${CMAKE_CURRENT_BINARY_DIR}/${f}.h")
 
 		# Get the proper name for the test variable.
 		get_filename_component(TEST_NAME ${f} NAME_WE)
 		add_custom_command(OUTPUT ${h}
 			COMMAND
 				"${Python_EXECUTABLE}"
 				"${CMAKE_CURRENT_SOURCE_DIR}/data/generate_header.py"
 				"${TEST_NAME}"
 				"${CMAKE_CURRENT_SOURCE_DIR}/${f}" > ${h}
 			MAIN_DEPENDENCY ${f}
 			DEPENDS
 				"data/generate_header.py"
 			VERBATIM
 		)
 		list(APPEND HEADERS ${h})
 	endforeach(f)
 	set(${NAME} "${HEADERS}" PARENT_SCOPE)
 endfunction()
 
 gen_json_header(JSON_HEADERS
 	data/base58_encode_decode.json
 	data/blockfilters.json
 	data/key_io_valid.json
 	data/key_io_invalid.json
 	data/script_tests.json
 	data/sighash.json
 	data/tx_invalid.json
 	data/tx_valid.json
 )
 
 include(TestSuite)
 create_test_suite(bitcoin)
 add_dependencies(check check-bitcoin)
 
 # An utility library for bitcoin related test suites.
 add_library(testutil OBJECT
 	util/blockfilter.cpp
 	util/logging.cpp
 	util/mining.cpp
 	util/setup_common.cpp
 	util/str.cpp
 	util/transaction_utils.cpp
 	util/wallet.cpp
 )
 
 target_link_libraries(testutil server)
 
 if(BUILD_BITCOIN_WALLET)
 	set(BITCOIN_WALLET_TEST_FIXTURE
 		../wallet/test/init_test_fixture.cpp
 		../wallet/test/wallet_test_fixture.cpp
 	)
 	set(BITCOIN_WALLET_TESTS
 		../wallet/test/db_tests.cpp
 		../wallet/test/coinselector_tests.cpp
 		../wallet/test/init_tests.cpp
 		../wallet/test/ismine_tests.cpp
 		../wallet/test/psbt_wallet_tests.cpp
 		../wallet/test/wallet_tests.cpp
 		../wallet/test/walletdb_tests.cpp
 		../wallet/test/wallet_crypto_tests.cpp
 	)
 endif()
 
 add_boost_unit_tests_to_suite(bitcoin test_bitcoin
 	fixture.cpp
 	jsonutil.cpp
 	scriptflags.cpp
 	sigutil.cpp
 
 	# Tests generated from JSON
 	${JSON_HEADERS}
 
 	# Wallet test fixture
 	${BITCOIN_WALLET_TEST_FIXTURE}
 
 	TESTS
 		activation_tests.cpp
 		addrman_tests.cpp
 		allocator_tests.cpp
 		amount_tests.cpp
 		arith_uint256_tests.cpp
 		base32_tests.cpp
 		base58_tests.cpp
 		base64_tests.cpp
 		bip32_tests.cpp
 		bitmanip_tests.cpp
 		blockchain_tests.cpp
 		blockcheck_tests.cpp
 		blockencodings_tests.cpp
 		blockfilter_tests.cpp
 		blockfilter_index_tests.cpp
 		blockindex_tests.cpp
 		blockstatus_tests.cpp
 		bloom_tests.cpp
 		bswap_tests.cpp
 		cashaddr_tests.cpp
 		cashaddrenc_tests.cpp
 		checkdatasig_tests.cpp
 		checkpoints_tests.cpp
 		checkqueue_tests.cpp
 		coins_tests.cpp
 		compilerbug_tests.cpp
 		compress_tests.cpp
 		config_tests.cpp
 		core_io_tests.cpp
 		crypto_tests.cpp
 		cuckoocache_tests.cpp
 		dbwrapper_tests.cpp
 		denialofservice_tests.cpp
 		descriptor_tests.cpp
 		dstencode_tests.cpp
 		excessiveblock_tests.cpp
 		feerate_tests.cpp
 		finalization_tests.cpp
 		flatfile_tests.cpp
 		fs_tests.cpp
 		getarg_tests.cpp
 		hash_tests.cpp
+		interfaces_tests.cpp
 		inv_tests.cpp
 		key_io_tests.cpp
 		key_tests.cpp
 		lcg_tests.cpp
 		limitedmap_tests.cpp
 		mempool_tests.cpp
 		merkle_tests.cpp
 		merkleblock_tests.cpp
 		miner_tests.cpp
 		monolith_opcodes_tests.cpp
 		multisig_tests.cpp
 		net_tests.cpp
 		netbase_tests.cpp
 		op_reversebytes_tests.cpp
 		pmt_tests.cpp
 		policyestimator_tests.cpp
 		prevector_tests.cpp
 		radix_tests.cpp
 		raii_event_tests.cpp
 		random_tests.cpp
 		rcu_tests.cpp
 		reverselock_tests.cpp
 		rpc_tests.cpp
 		rpc_server_tests.cpp
 		rwcollection_tests.cpp
 		sanity_tests.cpp
 		scheduler_tests.cpp
 		schnorr_tests.cpp
 		script_bitfield_tests.cpp
 		script_commitment_tests.cpp
 		script_p2sh_tests.cpp
 		script_standard_tests.cpp
 		script_tests.cpp
 		scriptnum_tests.cpp
 		serialize_tests.cpp
 		settings_tests.cpp
 		sigcache_tests.cpp
 		sigencoding_tests.cpp
 		sighash_tests.cpp
 		sighashtype_tests.cpp
 		sigcheckcount_tests.cpp
 		skiplist_tests.cpp
 		streams_tests.cpp
 		sync_tests.cpp
 		timedata_tests.cpp
 		torcontrol_tests.cpp
 		transaction_tests.cpp
 		txindex_tests.cpp
 		txvalidation_tests.cpp
 		txvalidationcache_tests.cpp
 		uint256_tests.cpp
 		undo_tests.cpp
 		util_tests.cpp
 		util_threadnames_tests.cpp
 		validation_block_tests.cpp
 		validation_tests.cpp
 		validationinterface_tests.cpp
 		versionbits_tests.cpp
 		work_comparator_tests.cpp
 
 		# RPC Tests
 		../rpc/test/server_tests.cpp
 
 		# Wallet tests
 		${BITCOIN_WALLET_TESTS}
 )
 
 function(add_boost_test_runners_with_upgrade_activated SUITE EXECUTABLE)
 	set(SUITE_UPGRADE_ACTIVATED "${SUITE}-upgrade-activated")
 	get_target_from_suite(${SUITE_UPGRADE_ACTIVATED} TARGET_UPGRADE_ACTIVATED)
 
 	if(NOT TARGET ${TARGET_UPGRADE_ACTIVATED})
 		create_test_suite_with_parent_targets(
 			${SUITE_UPGRADE_ACTIVATED}
 			check-upgrade-activated
 			check-upgrade-activated-extended
 		)
 		add_dependencies(${TARGET_UPGRADE_ACTIVATED} ${EXECUTABLE})
 	endif()
 
 	get_target_from_suite(${SUITE} SUITE_TARGET)
 	get_target_property(BOOST_TESTS ${SUITE_TARGET} UNIT_TESTS)
 
 	get_target_from_suite(${SUITE_UPGRADE_ACTIVATED} SUITE_UPGRADE_ACTIVATED_TARGET)
 
 	set(HRF_LOGGER "HRF,test_suite")
 
 	foreach(_test_name ${BOOST_TESTS})
 		if(ENABLE_JUNIT_REPORT)
 			set(JUNIT_LOGGER ":JUNIT,message,${SUITE_UPGRADE_ACTIVATED}-${_test_name}.xml")
 		endif()
 
 		add_test_runner(
 			${SUITE_UPGRADE_ACTIVATED}
 			"${_test_name}"
 			${EXECUTABLE}
 			JUNIT
 			"--run_test=${_test_name}"
 			"--logger=${HRF_LOGGER}${JUNIT_LOGGER}"
 			# Dec. 1st, 2019 at 00:00:00
 			--
 			"-testsuitename=Bitcoin ABC unit tests with next upgrade activated"
 			-axionactivationtime=1575158400
 		)
 	endforeach()
 endfunction()
 
 add_boost_test_runners_with_upgrade_activated(bitcoin test_bitcoin)
 
 target_link_libraries(test_bitcoin rpcclient testutil)
 if(TARGET bitcoinconsensus-shared)
 	target_link_libraries(test_bitcoin bitcoinconsensus-shared)
 else()
 	target_link_libraries(test_bitcoin bitcoinconsensus)
 endif()
 
 add_subdirectory(fuzz)
diff --git a/src/test/interfaces_tests.cpp b/src/test/interfaces_tests.cpp
new file mode 100644
index 000000000..66729da77
--- /dev/null
+++ b/src/test/interfaces_tests.cpp
@@ -0,0 +1,53 @@
+// Copyright (c) 2020 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <chainparams.h>
+#include <interfaces/chain.h>
+#include <test/util/setup_common.h>
+#include <validation.h>
+
+#include <boost/test/unit_test.hpp>
+
+using interfaces::FoundBlock;
+
+BOOST_FIXTURE_TEST_SUITE(interfaces_tests, TestChain100Setup)
+
+BOOST_AUTO_TEST_CASE(findBlock) {
+    auto chain = interfaces::MakeChain(m_node, Params());
+    auto &active = ChainActive();
+
+    BlockHash hash;
+    BOOST_CHECK(
+        chain->findBlock(active[10]->GetBlockHash(), FoundBlock().hash(hash)));
+    BOOST_CHECK_EQUAL(hash, active[10]->GetBlockHash());
+
+    int height = -1;
+    BOOST_CHECK(chain->findBlock(active[20]->GetBlockHash(),
+                                 FoundBlock().height(height)));
+    BOOST_CHECK_EQUAL(height, active[20]->nHeight);
+
+    CBlock data;
+    BOOST_CHECK(
+        chain->findBlock(active[30]->GetBlockHash(), FoundBlock().data(data)));
+    BOOST_CHECK_EQUAL(data.GetHash(), active[30]->GetBlockHash());
+
+    int64_t time = -1;
+    BOOST_CHECK(
+        chain->findBlock(active[40]->GetBlockHash(), FoundBlock().time(time)));
+    BOOST_CHECK_EQUAL(time, active[40]->GetBlockTime());
+
+    int64_t max_time = -1;
+    BOOST_CHECK(chain->findBlock(active[50]->GetBlockHash(),
+                                 FoundBlock().maxTime(max_time)));
+    BOOST_CHECK_EQUAL(max_time, active[50]->GetBlockTimeMax());
+
+    int64_t mtp_time = -1;
+    BOOST_CHECK(chain->findBlock(active[60]->GetBlockHash(),
+                                 FoundBlock().mtpTime(mtp_time)));
+    BOOST_CHECK_EQUAL(mtp_time, active[60]->GetMedianTimePast());
+
+    BOOST_CHECK(!chain->findBlock(BlockHash(), FoundBlock()));
+}
+
+BOOST_AUTO_TEST_SUITE_END()
diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp
index 4e1693031..9663688d4 100644
--- a/src/wallet/rpcwallet.cpp
+++ b/src/wallet/rpcwallet.cpp
@@ -1,4890 +1,4892 @@
 // Copyright (c) 2010 Satoshi Nakamoto
 // Copyright (c) 2009-2019 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <amount.h>
 #include <chainparams.h> // for GetConsensus.
 #include <coins.h>
 #include <config.h>
 #include <consensus/validation.h>
 #include <core_io.h>
 #include <interfaces/chain.h>
 #include <key_io.h>
 #include <node/context.h>
 #include <outputtype.h>
 #include <policy/fees.h>
 #include <rpc/rawtransaction_util.h>
 #include <rpc/server.h>
 #include <rpc/util.h>
 #include <script/descriptor.h>
 #include <util/bip32.h>
 #include <util/error.h>
 #include <util/moneystr.h>
 #include <util/string.h>
 #include <util/system.h>
 #include <util/translation.h>
 #include <util/url.h>
 #include <util/validation.h>
 #include <validation.h>
 #include <wallet/coincontrol.h>
 #include <wallet/psbtwallet.h>
 #include <wallet/rpcwallet.h>
 #include <wallet/wallet.h>
 #include <wallet/walletdb.h>
 #include <wallet/walletutil.h>
 
 #include <univalue.h>
 
 #include <event2/http.h>
 
+using interfaces::FoundBlock;
+
 static const std::string WALLET_ENDPOINT_BASE = "/wallet/";
 
 static inline bool GetAvoidReuseFlag(CWallet *const pwallet,
                                      const UniValue &param) {
     bool can_avoid_reuse = pwallet->IsWalletFlagSet(WALLET_FLAG_AVOID_REUSE);
     bool avoid_reuse = param.isNull() ? can_avoid_reuse : param.get_bool();
 
     if (avoid_reuse && !can_avoid_reuse) {
         throw JSONRPCError(
             RPC_WALLET_ERROR,
             "wallet does not have the \"avoid reuse\" feature enabled");
     }
 
     return avoid_reuse;
 }
 
 /**
  * Used by RPC commands that have an include_watchonly parameter. We default to
  * true for watchonly wallets if include_watchonly isn't explicitly set.
  */
 static bool ParseIncludeWatchonly(const UniValue &include_watchonly,
                                   const CWallet &pwallet) {
     if (include_watchonly.isNull()) {
         // if include_watchonly isn't explicitly set, then check if we have a
         // watchonly wallet
         return pwallet.IsWalletFlagSet(WALLET_FLAG_DISABLE_PRIVATE_KEYS);
     }
 
     // otherwise return whatever include_watchonly was set to
     return include_watchonly.get_bool();
 }
 
 /**
  * Checks if a CKey is in the given CWallet compressed or otherwise
  */
 bool HaveKey(const SigningProvider &wallet, const CKey &key) {
     CKey key2;
     key2.Set(key.begin(), key.end(), !key.IsCompressed());
     return wallet.HaveKey(key.GetPubKey().GetID()) ||
            wallet.HaveKey(key2.GetPubKey().GetID());
 }
 
 bool GetWalletNameFromJSONRPCRequest(const JSONRPCRequest &request,
                                      std::string &wallet_name) {
     if (request.URI.substr(0, WALLET_ENDPOINT_BASE.size()) ==
         WALLET_ENDPOINT_BASE) {
         // wallet endpoint was used
         wallet_name =
             urlDecode(request.URI.substr(WALLET_ENDPOINT_BASE.size()));
         return true;
     }
     return false;
 }
 
 std::shared_ptr<CWallet>
 GetWalletForJSONRPCRequest(const JSONRPCRequest &request) {
     std::string wallet_name;
     if (GetWalletNameFromJSONRPCRequest(request, wallet_name)) {
         std::shared_ptr<CWallet> pwallet = GetWallet(wallet_name);
         if (!pwallet) {
             throw JSONRPCError(
                 RPC_WALLET_NOT_FOUND,
                 "Requested wallet does not exist or is not loaded");
         }
         return pwallet;
     }
 
     std::vector<std::shared_ptr<CWallet>> wallets = GetWallets();
     return wallets.size() == 1 || (request.fHelp && wallets.size() > 0)
                ? wallets[0]
                : nullptr;
 }
 
 std::string HelpRequiringPassphrase(const CWallet *pwallet) {
     return pwallet && pwallet->IsCrypted()
                ? "\nRequires wallet passphrase to be set with walletpassphrase "
                  "call."
                : "";
 }
 
 bool EnsureWalletIsAvailable(const CWallet *pwallet, bool avoidException) {
     if (pwallet) {
         return true;
     }
     if (avoidException) {
         return false;
     }
     if (!HasWallets()) {
         throw JSONRPCError(RPC_METHOD_NOT_FOUND,
                            "Method not found (wallet method is disabled "
                            "because no wallet is loaded)");
     }
 
     throw JSONRPCError(RPC_WALLET_NOT_SPECIFIED,
                        "Wallet file not specified (must request wallet RPC "
                        "through /wallet/<filename> uri-path).");
 }
 
 void EnsureWalletIsUnlocked(const CWallet *pwallet) {
     if (pwallet->IsLocked()) {
         throw JSONRPCError(RPC_WALLET_UNLOCK_NEEDED,
                            "Error: Please enter the wallet passphrase with "
                            "walletpassphrase first.");
     }
 }
 
 // also_create should only be set to true only when the RPC is expected to add
 // things to a blank wallet and make it no longer blank
 LegacyScriptPubKeyMan &EnsureLegacyScriptPubKeyMan(CWallet &wallet,
                                                    bool also_create) {
     LegacyScriptPubKeyMan *spk_man = wallet.GetLegacyScriptPubKeyMan();
     if (!spk_man && also_create) {
         spk_man = wallet.GetOrCreateLegacyScriptPubKeyMan();
     }
     if (!spk_man) {
         throw JSONRPCError(RPC_WALLET_ERROR,
                            "This type of wallet does not support this command");
     }
     return *spk_man;
 }
 
 static void WalletTxToJSON(interfaces::Chain &chain,
                            interfaces::Chain::Lock &locked_chain,
                            const CWalletTx &wtx, UniValue &entry) {
     int confirms = wtx.GetDepthInMainChain();
     entry.pushKV("confirmations", confirms);
     if (wtx.IsCoinBase()) {
         entry.pushKV("generated", true);
     }
     if (confirms > 0) {
         entry.pushKV("blockhash", wtx.m_confirm.hashBlock.GetHex());
         entry.pushKV("blockheight", wtx.m_confirm.block_height);
         entry.pushKV("blockindex", wtx.m_confirm.nIndex);
         int64_t block_time;
-        bool found_block = chain.findBlock(wtx.m_confirm.hashBlock,
-                                           nullptr /* block */, &block_time);
-        CHECK_NONFATAL(found_block);
+        CHECK_NONFATAL(chain.findBlock(wtx.m_confirm.hashBlock,
+                                       FoundBlock().time(block_time)));
         entry.pushKV("blocktime", block_time);
     } else {
         entry.pushKV("trusted", wtx.IsTrusted(locked_chain));
     }
     uint256 hash = wtx.GetId();
     entry.pushKV("txid", hash.GetHex());
     UniValue conflicts(UniValue::VARR);
     for (const uint256 &conflict : wtx.GetConflicts()) {
         conflicts.push_back(conflict.GetHex());
     }
     entry.pushKV("walletconflicts", conflicts);
     entry.pushKV("time", wtx.GetTxTime());
     entry.pushKV("timereceived", (int64_t)wtx.nTimeReceived);
 
     for (const std::pair<const std::string, std::string> &item : wtx.mapValue) {
         entry.pushKV(item.first, item.second);
     }
 }
 
 static std::string LabelFromValue(const UniValue &value) {
     std::string label = value.get_str();
     if (label == "*") {
         throw JSONRPCError(RPC_WALLET_INVALID_LABEL_NAME, "Invalid label name");
     }
     return label;
 }
 
 static UniValue getnewaddress(const Config &config,
                               const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "getnewaddress",
         "Returns a new Bitcoin address for receiving payments.\n"
         "If 'label' is specified, it is added to the address book \n"
         "so payments received with the address will be associated with "
         "'label'.\n",
         {
             {"label", RPCArg::Type::STR, /* default */ "null",
              "The label name for the address to be linked to. If not provided, "
              "the default label \"\" is used. It can also be set to the empty "
              "string \"\" to represent the default label. The label does not "
              "need to exist, it will be created if there is no label by the "
              "given name."},
             {"address_type", RPCArg::Type::STR,
              /* default */ "set by -addresstype",
              "The address type to use. Options are \"legacy\"."},
         },
         RPCResult{"\"address\"    (string) The new bitcoin address\n"},
         RPCExamples{HelpExampleCli("getnewaddress", "") +
                     HelpExampleRpc("getnewaddress", "")},
     }
         .Check(request);
 
     LOCK(pwallet->cs_wallet);
 
     if (!pwallet->CanGetAddresses()) {
         throw JSONRPCError(RPC_WALLET_ERROR,
                            "Error: This wallet has no available keys");
     }
 
     // Parse the label first so we don't generate a key if there's an error
     std::string label;
     if (!request.params[0].isNull()) {
         label = LabelFromValue(request.params[0]);
     }
 
     OutputType output_type = pwallet->m_default_address_type;
     if (!request.params[1].isNull()) {
         if (!ParseOutputType(request.params[1].get_str(), output_type)) {
             throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY,
                                strprintf("Unknown address type '%s'",
                                          request.params[1].get_str()));
         }
     }
 
     CTxDestination dest;
     std::string error;
     if (!pwallet->GetNewDestination(output_type, label, dest, error)) {
         throw JSONRPCError(RPC_WALLET_KEYPOOL_RAN_OUT, error);
     }
 
     return EncodeDestination(dest, config);
 }
 
 static UniValue getrawchangeaddress(const Config &config,
                                     const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "getrawchangeaddress",
         "Returns a new Bitcoin address, for receiving change.\n"
         "This is for use with raw transactions, NOT normal use.\n",
         {},
         RPCResult{"\"address\"    (string) The address\n"},
         RPCExamples{HelpExampleCli("getrawchangeaddress", "") +
                     HelpExampleRpc("getrawchangeaddress", "")},
     }
         .Check(request);
 
     LOCK(pwallet->cs_wallet);
 
     if (!pwallet->CanGetAddresses(true)) {
         throw JSONRPCError(RPC_WALLET_ERROR,
                            "Error: This wallet has no available keys");
     }
 
     OutputType output_type =
         pwallet->m_default_change_type != OutputType::CHANGE_AUTO
             ? pwallet->m_default_change_type
             : pwallet->m_default_address_type;
     if (!request.params[0].isNull()) {
         if (!ParseOutputType(request.params[0].get_str(), output_type)) {
             throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY,
                                strprintf("Unknown address type '%s'",
                                          request.params[0].get_str()));
         }
     }
 
     CTxDestination dest;
     std::string error;
     if (!pwallet->GetNewChangeDestination(output_type, dest, error)) {
         throw JSONRPCError(RPC_WALLET_KEYPOOL_RAN_OUT, error);
     }
     return EncodeDestination(dest, config);
 }
 
 static UniValue setlabel(const Config &config, const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "setlabel",
         "Sets the label associated with the given address.\n",
         {
             {"address", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The bitcoin address to be associated with a label."},
             {"label", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The label to assign to the address."},
         },
         RPCResults{},
         RPCExamples{
             HelpExampleCli("setlabel",
                            "\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX\" \"tabby\"") +
             HelpExampleRpc(
                 "setlabel",
                 "\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX\", \"tabby\"")},
     }
         .Check(request);
 
     LOCK(pwallet->cs_wallet);
 
     CTxDestination dest =
         DecodeDestination(request.params[0].get_str(), wallet->chainParams);
     if (!IsValidDestination(dest)) {
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY,
                            "Invalid Bitcoin address");
     }
 
     std::string label = LabelFromValue(request.params[1]);
 
     if (pwallet->IsMine(dest)) {
         pwallet->SetAddressBook(dest, label, "receive");
     } else {
         pwallet->SetAddressBook(dest, label, "send");
     }
 
     return NullUniValue;
 }
 
 static CTransactionRef SendMoney(interfaces::Chain::Lock &locked_chain,
                                  CWallet *const pwallet,
                                  const CTxDestination &address, Amount nValue,
                                  bool fSubtractFeeFromAmount,
                                  const CCoinControl &coin_control,
                                  mapValue_t mapValue) {
     Amount curBalance =
         pwallet->GetBalance(0, coin_control.m_avoid_address_reuse)
             .m_mine_trusted;
 
     // Check amount
     if (nValue <= Amount::zero()) {
         throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid amount");
     }
 
     if (nValue > curBalance) {
         throw JSONRPCError(RPC_WALLET_INSUFFICIENT_FUNDS, "Insufficient funds");
     }
 
     // Parse Bitcoin address
     CScript scriptPubKey = GetScriptForDestination(address);
 
     // Create and send the transaction
     Amount nFeeRequired;
     bilingual_str error;
     std::vector<CRecipient> vecSend;
     int nChangePosRet = -1;
     CRecipient recipient = {scriptPubKey, nValue, fSubtractFeeFromAmount};
     vecSend.push_back(recipient);
 
     CTransactionRef tx;
     if (!pwallet->CreateTransaction(locked_chain, vecSend, tx, nFeeRequired,
                                     nChangePosRet, error, coin_control)) {
         if (!fSubtractFeeFromAmount && nValue + nFeeRequired > curBalance) {
             error = strprintf(Untranslated("Error: This transaction requires a "
                                            "transaction fee of at least %s"),
                               FormatMoney(nFeeRequired));
         }
         throw JSONRPCError(RPC_WALLET_ERROR, error.original);
     }
     pwallet->CommitTransaction(tx, std::move(mapValue), {} /* orderForm */);
     return tx;
 }
 
 static UniValue sendtoaddress(const Config &config,
                               const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "sendtoaddress",
         "Send an amount to a given address.\n" +
             HelpRequiringPassphrase(pwallet) + "\n",
         {
             {"address", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The bitcoin address to send to."},
             {"amount", RPCArg::Type::AMOUNT, RPCArg::Optional::NO,
              "The amount in " + CURRENCY_UNIT + " to send. eg 0.1"},
             {"comment", RPCArg::Type::STR, RPCArg::Optional::OMITTED_NAMED_ARG,
              "A comment used to store what the transaction is for.\n"
              "                             This is not part of the "
              "transaction, just kept in your wallet."},
             {"comment_to", RPCArg::Type::STR,
              RPCArg::Optional::OMITTED_NAMED_ARG,
              "A comment to store the name of the person or organization\n"
              "                             to which you're sending the "
              "transaction. This is not part of the \n"
              "                             transaction, just kept in "
              "your wallet."},
             {"subtractfeefromamount", RPCArg::Type::BOOL,
              /* default */ "false",
              "The fee will be deducted from the amount being sent.\n"
              "                             The recipient will receive "
              "less bitcoins than you enter in the amount field."},
             {"avoid_reuse", RPCArg::Type::BOOL,
              /* default */ "true",
              "(only available if avoid_reuse wallet flag is set) Avoid "
              "spending from dirty addresses; addresses are considered\n"
              "                             dirty if they have previously "
              "been used in a transaction."},
         },
         RPCResult{"\"txid\"                  (string) The transaction id.\n"},
         RPCExamples{
             HelpExampleCli("sendtoaddress",
                            "\"1M72Sfpbz1BPpXFHz9m3CdqATR44Jvaydd\" 0.1") +
             HelpExampleCli("sendtoaddress", "\"1M72Sfpbz1BPpXFHz9m3CdqATR44Jvay"
                                             "dd\" 0.1 \"donation\" \"seans "
                                             "outpost\"") +
             HelpExampleCli("sendtoaddress", "\"1M72Sfpbz1BPpXFHz9m3CdqATR44"
                                             "Jvaydd\" 0.1 \"\" \"\" true") +
             HelpExampleRpc("sendtoaddress", "\"1M72Sfpbz1BPpXFHz9m3CdqATR44Jvay"
                                             "dd\", 0.1, \"donation\", \"seans "
                                             "outpost\"")},
     }
         .Check(request);
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     CTxDestination dest =
         DecodeDestination(request.params[0].get_str(), wallet->chainParams);
     if (!IsValidDestination(dest)) {
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Invalid address");
     }
 
     // Amount
     Amount nAmount = AmountFromValue(request.params[1]);
     if (nAmount <= Amount::zero()) {
         throw JSONRPCError(RPC_TYPE_ERROR, "Invalid amount for send");
     }
 
     // Wallet comments
     mapValue_t mapValue;
     if (!request.params[2].isNull() && !request.params[2].get_str().empty()) {
         mapValue["comment"] = request.params[2].get_str();
     }
     if (!request.params[3].isNull() && !request.params[3].get_str().empty()) {
         mapValue["to"] = request.params[3].get_str();
     }
 
     bool fSubtractFeeFromAmount = false;
     if (!request.params[4].isNull()) {
         fSubtractFeeFromAmount = request.params[4].get_bool();
     }
 
     CCoinControl coin_control;
     coin_control.m_avoid_address_reuse =
         GetAvoidReuseFlag(pwallet, request.params[5]);
     // We also enable partial spend avoidance if reuse avoidance is set.
     coin_control.m_avoid_partial_spends |= coin_control.m_avoid_address_reuse;
 
     EnsureWalletIsUnlocked(pwallet);
 
     CTransactionRef tx =
         SendMoney(*locked_chain, pwallet, dest, nAmount, fSubtractFeeFromAmount,
                   coin_control, std::move(mapValue));
     return tx->GetId().GetHex();
 }
 
 static UniValue listaddressgroupings(const Config &config,
                                      const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "listaddressgroupings",
         "Lists groups of addresses which have had their common ownership\n"
         "made public by common use as inputs or as the resulting change\n"
         "in past transactions\n",
         {},
         RPCResult{"[\n"
                   "  [\n"
                   "    [\n"
                   "      \"address\",            (string) The bitcoin address\n"
                   "      amount,                 (numeric) The amount in " +
                   CURRENCY_UNIT +
                   "\n"
                   "      \"label\"               (string, optional) The label\n"
                   "    ]\n"
                   "    ,...\n"
                   "  ]\n"
                   "  ,...\n"
                   "]\n"},
         RPCExamples{HelpExampleCli("listaddressgroupings", "") +
                     HelpExampleRpc("listaddressgroupings", "")},
     }
         .Check(request);
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     UniValue jsonGroupings(UniValue::VARR);
     std::map<CTxDestination, Amount> balances =
         pwallet->GetAddressBalances(*locked_chain);
     for (const std::set<CTxDestination> &grouping :
          pwallet->GetAddressGroupings()) {
         UniValue jsonGrouping(UniValue::VARR);
         for (const CTxDestination &address : grouping) {
             UniValue addressInfo(UniValue::VARR);
             addressInfo.push_back(EncodeDestination(address, config));
             addressInfo.push_back(ValueFromAmount(balances[address]));
 
             const auto *address_book_entry =
                 pwallet->FindAddressBookEntry(address);
             if (address_book_entry) {
                 addressInfo.push_back(address_book_entry->GetLabel());
             }
             jsonGrouping.push_back(addressInfo);
         }
         jsonGroupings.push_back(jsonGrouping);
     }
 
     return jsonGroupings;
 }
 
 static UniValue signmessage(const Config &config,
                             const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "signmessage",
         "Sign a message with the private key of an address" +
             HelpRequiringPassphrase(pwallet) + "\n",
         {
             {"address", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The bitcoin address to use for the private key."},
             {"message", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The message to create a signature of."},
         },
         RPCResult{"\"signature\"          (string) The signature of the "
                   "message encoded in base 64\n"},
         RPCExamples{
             "\nUnlock the wallet for 30 seconds\n" +
             HelpExampleCli("walletpassphrase", "\"mypassphrase\" 30") +
             "\nCreate the signature\n" +
             HelpExampleCli(
                 "signmessage",
                 "\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX\" \"my message\"") +
             "\nVerify the signature\n" +
             HelpExampleCli("verifymessage",
                            "\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX\" "
                            "\"signature\" \"my message\"") +
             "\nAs a JSON-RPC call\n" +
             HelpExampleRpc(
                 "signmessage",
                 "\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX\", \"my message\"")},
     }
         .Check(request);
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     EnsureWalletIsUnlocked(pwallet);
 
     std::string strAddress = request.params[0].get_str();
     std::string strMessage = request.params[1].get_str();
 
     CTxDestination dest = DecodeDestination(strAddress, wallet->chainParams);
     if (!IsValidDestination(dest)) {
         throw JSONRPCError(RPC_TYPE_ERROR, "Invalid address");
     }
 
     const PKHash *pkhash = boost::get<PKHash>(&dest);
     if (!pkhash) {
         throw JSONRPCError(RPC_TYPE_ERROR, "Address does not refer to key");
     }
 
     CScript script_pub_key = GetScriptForDestination(*pkhash);
     std::unique_ptr<SigningProvider> provider =
         pwallet->GetSigningProvider(script_pub_key);
     if (!provider) {
         throw JSONRPCError(RPC_WALLET_ERROR, "Private key not available");
     }
 
     CKey key;
     CKeyID keyID(*pkhash);
     if (!provider->GetKey(keyID, key)) {
         throw JSONRPCError(RPC_WALLET_ERROR, "Private key not available");
     }
 
     CHashWriter ss(SER_GETHASH, 0);
     ss << strMessageMagic;
     ss << strMessage;
 
     std::vector<uint8_t> vchSig;
     if (!key.SignCompact(ss.GetHash(), vchSig)) {
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Sign failed");
     }
 
     return EncodeBase64(vchSig.data(), vchSig.size());
 }
 
 static UniValue getreceivedbyaddress(const Config &config,
                                      const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "getreceivedbyaddress",
         "Returns the total amount received by the given address in "
         "transactions with at least minconf confirmations.\n",
         {
             {"address", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The bitcoin address for transactions."},
             {"minconf", RPCArg::Type::NUM, /* default */ "1",
              "Only include transactions confirmed at least this many times."},
         },
         RPCResult{"amount   (numeric) The total amount in " + CURRENCY_UNIT +
                   " received at this address.\n"},
         RPCExamples{
             "\nThe amount from transactions with at least 1 confirmation\n" +
             HelpExampleCli("getreceivedbyaddress",
                            "\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX\"") +
             "\nThe amount including unconfirmed transactions, zero "
             "confirmations\n" +
             HelpExampleCli("getreceivedbyaddress",
                            "\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX\" 0") +
             "\nThe amount with at least 6 confirmations\n" +
             HelpExampleCli("getreceivedbyaddress",
                            "\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX\" 6") +
             "\nAs a JSON-RPC call\n" +
             HelpExampleRpc("getreceivedbyaddress",
                            "\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX\", 6")},
     }
         .Check(request);
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     // Bitcoin address
     CTxDestination dest =
         DecodeDestination(request.params[0].get_str(), wallet->chainParams);
     if (!IsValidDestination(dest)) {
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY,
                            "Invalid Bitcoin address");
     }
     CScript scriptPubKey = GetScriptForDestination(dest);
     if (!pwallet->IsMine(scriptPubKey)) {
         throw JSONRPCError(RPC_WALLET_ERROR, "Address not found in wallet");
     }
 
     // Minimum confirmations
     int nMinDepth = 1;
     if (!request.params[1].isNull()) {
         nMinDepth = request.params[1].get_int();
     }
 
     // Tally
     Amount nAmount = Amount::zero();
     for (const std::pair<const TxId, CWalletTx> &pairWtx : pwallet->mapWallet) {
         const CWalletTx &wtx = pairWtx.second;
 
         TxValidationState state;
         if (wtx.IsCoinBase() ||
             !locked_chain->contextualCheckTransactionForCurrentBlock(
                 wallet->chainParams.GetConsensus(), *wtx.tx, state)) {
             continue;
         }
 
         for (const CTxOut &txout : wtx.tx->vout) {
             if (txout.scriptPubKey == scriptPubKey) {
                 if (wtx.GetDepthInMainChain() >= nMinDepth) {
                     nAmount += txout.nValue;
                 }
             }
         }
     }
 
     return ValueFromAmount(nAmount);
 }
 
 static UniValue getreceivedbylabel(const Config &config,
                                    const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "getreceivedbylabel",
         "Returns the total amount received by addresses with <label> in "
         "transactions with at least [minconf] confirmations.\n",
         {
             {"label", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The selected label, may be the default label using \"\"."},
             {"minconf", RPCArg::Type::NUM, /* default */ "1",
              "Only include transactions confirmed at least this many times."},
         },
         RPCResult{"amount              (numeric) The total amount in " +
                   CURRENCY_UNIT + " received for this label.\n"},
         RPCExamples{"\nAmount received by the default label with at least 1 "
                     "confirmation\n" +
                     HelpExampleCli("getreceivedbylabel", "\"\"") +
                     "\nAmount received at the tabby label including "
                     "unconfirmed amounts with zero confirmations\n" +
                     HelpExampleCli("getreceivedbylabel", "\"tabby\" 0") +
                     "\nThe amount with at least 6 confirmations\n" +
                     HelpExampleCli("getreceivedbylabel", "\"tabby\" 6") +
                     "\nAs a JSON-RPC call\n" +
                     HelpExampleRpc("getreceivedbylabel", "\"tabby\", 6")},
     }
         .Check(request);
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     // Minimum confirmations
     int nMinDepth = 1;
     if (!request.params[1].isNull()) {
         nMinDepth = request.params[1].get_int();
     }
 
     // Get the set of pub keys assigned to label
     std::string label = LabelFromValue(request.params[0]);
     std::set<CTxDestination> setAddress = pwallet->GetLabelAddresses(label);
 
     // Tally
     Amount nAmount = Amount::zero();
     for (const std::pair<const TxId, CWalletTx> &pairWtx : pwallet->mapWallet) {
         const CWalletTx &wtx = pairWtx.second;
         TxValidationState state;
         if (wtx.IsCoinBase() ||
             !locked_chain->contextualCheckTransactionForCurrentBlock(
                 wallet->chainParams.GetConsensus(), *wtx.tx, state)) {
             continue;
         }
 
         for (const CTxOut &txout : wtx.tx->vout) {
             CTxDestination address;
             if (ExtractDestination(txout.scriptPubKey, address) &&
                 pwallet->IsMine(address) && setAddress.count(address)) {
                 if (wtx.GetDepthInMainChain() >= nMinDepth) {
                     nAmount += txout.nValue;
                 }
             }
         }
     }
 
     return ValueFromAmount(nAmount);
 }
 
 static UniValue getbalance(const Config &config,
                            const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "getbalance",
         "Returns the total available balance.\n"
         "The available balance is what the wallet considers currently "
         "spendable, and is\n"
         "thus affected by options which limit spendability such as "
         "-spendzeroconfchange.\n",
         {
             {"dummy", RPCArg::Type::STR, RPCArg::Optional::OMITTED_NAMED_ARG,
              "Remains for backward compatibility. Must be excluded or set to "
              "\"*\"."},
             {"minconf", RPCArg::Type::NUM, /* default */ "0",
              "Only include transactions confirmed at least this many times."},
             {"include_watchonly", RPCArg::Type::BOOL,
              /* default */ "true for watch-only wallets, otherwise false",
              "Also include balance in watch-only addresses (see "
              "'importaddress')"},
             {"avoid_reuse", RPCArg::Type::BOOL,
              /* default */ "true",
              "(only available if avoid_reuse wallet flag is set) Do not "
              "include balance in dirty outputs; addresses are considered dirty "
              "if they have previously been used in a transaction."},
         },
         RPCResult{"amount              (numeric) The total amount in " +
                   CURRENCY_UNIT + " received for this wallet.\n"},
         RPCExamples{
             "\nThe total amount in the wallet with 1 or more confirmations\n" +
             HelpExampleCli("getbalance", "") +
             "\nThe total amount in the wallet at least 6 blocks confirmed\n" +
             HelpExampleCli("getbalance", "\"*\" 6") + "\nAs a JSON-RPC call\n" +
             HelpExampleRpc("getbalance", "\"*\", 6")},
     }
         .Check(request);
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     const UniValue &dummy_value = request.params[0];
     if (!dummy_value.isNull() && dummy_value.get_str() != "*") {
         throw JSONRPCError(
             RPC_METHOD_DEPRECATED,
             "dummy first argument must be excluded or set to \"*\".");
     }
 
     int min_depth = 0;
     if (!request.params[1].isNull()) {
         min_depth = request.params[1].get_int();
     }
 
     bool include_watchonly = ParseIncludeWatchonly(request.params[2], *pwallet);
 
     bool avoid_reuse = GetAvoidReuseFlag(pwallet, request.params[3]);
 
     const auto bal = pwallet->GetBalance(min_depth, avoid_reuse);
 
     return ValueFromAmount(bal.m_mine_trusted + (include_watchonly
                                                      ? bal.m_watchonly_trusted
                                                      : Amount::zero()));
 }
 
 static UniValue getunconfirmedbalance(const Config &config,
                                       const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "getunconfirmedbalance",
         "DEPRECATED\nIdentical to getbalances().mine.untrusted_pending\n",
         {},
         RPCResults{},
         RPCExamples{""},
     }
         .Check(request);
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     return ValueFromAmount(pwallet->GetBalance().m_mine_untrusted_pending);
 }
 
 static UniValue sendmany(const Config &config, const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "sendmany",
         "Send multiple times. Amounts are double-precision "
         "floating point numbers." +
             HelpRequiringPassphrase(pwallet) + "\n",
         {
             {"dummy", RPCArg::Type::STR, RPCArg::Optional::NO,
              "Must be set to \"\" for backwards compatibility.", "\"\""},
             {
                 "amounts",
                 RPCArg::Type::OBJ,
                 RPCArg::Optional::NO,
                 "A json object with addresses and amounts",
                 {
                     {"address", RPCArg::Type::AMOUNT, RPCArg::Optional::NO,
                      "The bitcoin address is the key, the numeric amount (can "
                      "be string) in " +
                          CURRENCY_UNIT + " is the value"},
                 },
             },
             {"minconf", RPCArg::Type::NUM, /* default */ "1",
              "Only use the balance confirmed at least this many times."},
             {"comment", RPCArg::Type::STR, RPCArg::Optional::OMITTED_NAMED_ARG,
              "A comment"},
             {
                 "subtractfeefrom",
                 RPCArg::Type::ARR,
                 RPCArg::Optional::OMITTED_NAMED_ARG,
                 "A json array with addresses.\n"
                 "                           The fee will be equally deducted "
                 "from the amount of each selected address.\n"
                 "                           Those recipients will receive less "
                 "bitcoins than you enter in their corresponding amount field.\n"
                 "                           If no addresses are specified "
                 "here, the sender pays the fee.",
                 {
                     {"address", RPCArg::Type::STR, RPCArg::Optional::OMITTED,
                      "Subtract fee from this address"},
                 },
             },
         },
         RPCResult{
             "\"txid\"                   (string) The transaction id for the "
             "send. Only 1 transaction is created regardless of \n"
             "                                    the number of addresses.\n"},
         RPCExamples{
             "\nSend two amounts to two different addresses:\n" +
             HelpExampleCli(
                 "sendmany",
                 "\"\" "
                 "\"{\\\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX\\\":0.01,"
                 "\\\"1353tsE8YMTA4EuV7dgUXGjNFf9KpVvKHz\\\":0.02}\"") +
             "\nSend two amounts to two different addresses setting the "
             "confirmation and comment:\n" +
             HelpExampleCli("sendmany",
                            "\"\" "
                            "\"{\\\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX\\\":0.01,"
                            "\\\"1353tsE8YMTA4EuV7dgUXGjNFf9KpVvKHz\\\":0.02}\" "
                            "6 \"testing\"") +
             "\nSend two amounts to two different addresses, subtract fee "
             "from amount:\n" +
             HelpExampleCli(
                 "sendmany",
                 "\"\" "
                 "\"{\\\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX\\\":0.01,"
                 "\\\"1353tsE8YMTA4EuV7dgUXGjNFf9KpVvKHz\\\":0.02}\" 1 \"\" "
                 "\"[\\\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX\\\","
                 "\\\"1353tsE8YMTA4EuV7dgUXGjNFf9KpVvKHz\\\"]\"") +
             "\nAs a JSON-RPC call\n" +
             HelpExampleRpc("sendmany",
                            "\"\", "
                            "\"{\\\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX\\\":0.01,"
                            "\\\"1353tsE8YMTA4EuV7dgUXGjNFf9KpVvKHz\\\":0.02}\","
                            " 6, \"testing\"")},
     }
         .Check(request);
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     if (!request.params[0].isNull() && !request.params[0].get_str().empty()) {
         throw JSONRPCError(RPC_INVALID_PARAMETER,
                            "Dummy value must be set to \"\"");
     }
     UniValue sendTo = request.params[1].get_obj();
 
     mapValue_t mapValue;
     if (!request.params[3].isNull() && !request.params[3].get_str().empty()) {
         mapValue["comment"] = request.params[3].get_str();
     }
 
     UniValue subtractFeeFromAmount(UniValue::VARR);
     if (!request.params[4].isNull()) {
         subtractFeeFromAmount = request.params[4].get_array();
     }
 
     std::set<CTxDestination> destinations;
     std::vector<CRecipient> vecSend;
 
     std::vector<std::string> keys = sendTo.getKeys();
     for (const std::string &name_ : keys) {
         CTxDestination dest = DecodeDestination(name_, wallet->chainParams);
         if (!IsValidDestination(dest)) {
             throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY,
                                std::string("Invalid Bitcoin address: ") +
                                    name_);
         }
 
         if (destinations.count(dest)) {
             throw JSONRPCError(
                 RPC_INVALID_PARAMETER,
                 std::string("Invalid parameter, duplicated address: ") + name_);
         }
         destinations.insert(dest);
 
         CScript scriptPubKey = GetScriptForDestination(dest);
         Amount nAmount = AmountFromValue(sendTo[name_]);
         if (nAmount <= Amount::zero()) {
             throw JSONRPCError(RPC_TYPE_ERROR, "Invalid amount for send");
         }
 
         bool fSubtractFeeFromAmount = false;
         for (size_t idx = 0; idx < subtractFeeFromAmount.size(); idx++) {
             const UniValue &addr = subtractFeeFromAmount[idx];
             if (addr.get_str() == name_) {
                 fSubtractFeeFromAmount = true;
             }
         }
 
         CRecipient recipient = {scriptPubKey, nAmount, fSubtractFeeFromAmount};
         vecSend.push_back(recipient);
     }
 
     EnsureWalletIsUnlocked(pwallet);
 
     // Shuffle recipient list
     std::shuffle(vecSend.begin(), vecSend.end(), FastRandomContext());
 
     // Send
     Amount nFeeRequired = Amount::zero();
     int nChangePosRet = -1;
     bilingual_str error;
     CTransactionRef tx;
     CCoinControl coinControl;
     bool fCreated =
         pwallet->CreateTransaction(*locked_chain, vecSend, tx, nFeeRequired,
                                    nChangePosRet, error, coinControl);
     if (!fCreated) {
         throw JSONRPCError(RPC_WALLET_INSUFFICIENT_FUNDS, error.original);
     }
     pwallet->CommitTransaction(tx, std::move(mapValue), {} /* orderForm */);
     return tx->GetId().GetHex();
 }
 
 static UniValue addmultisigaddress(const Config &config,
                                    const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "addmultisigaddress",
         "Add an nrequired-to-sign multisignature address to the wallet. "
         "Requires a new wallet backup.\n"
         "Each key is a Bitcoin address or hex-encoded public key.\n"
         "If 'label' is specified (DEPRECATED), assign address to that label.\n",
         {
             {"nrequired", RPCArg::Type::NUM, RPCArg::Optional::NO,
              "The number of required signatures out of the n keys or "
              "addresses."},
             {
                 "keys",
                 RPCArg::Type::ARR,
                 RPCArg::Optional::NO,
                 "A json array of bitcoin addresses or hex-encoded public keys",
                 {
                     {"key", RPCArg::Type::STR, RPCArg::Optional::OMITTED,
                      "bitcoin address or hex-encoded public key"},
                 },
             },
             {"label", RPCArg::Type::STR, RPCArg::Optional::OMITTED_NAMED_ARG,
              "A label to assign the addresses to."},
         },
         RPCResult{"{\n"
                   "  \"address\":\"multisigaddress\",    (string) The value of "
                   "the new multisig address.\n"
                   "  \"redeemScript\":\"script\"         (string) The string "
                   "value of the hex-encoded redemption script.\n"
                   "}\n"},
         RPCExamples{
             "\nAdd a multisig address from 2 addresses\n" +
             HelpExampleCli("addmultisigaddress",
                            "2 "
                            "\"[\\\"16sSauSf5pF2UkUwvKGq4qjNRzBZYqgEL5\\\","
                            "\\\"171sgjn4YtPu27adkKGrdDwzRTxnRkBfKV\\\"]\"") +
             "\nAs a JSON-RPC call\n" +
             HelpExampleRpc("addmultisigaddress",
                            "2, "
                            "\"[\\\"16sSauSf5pF2UkUwvKGq4qjNRzBZYqgEL5\\\","
                            "\\\"171sgjn4YtPu27adkKGrdDwzRTxnRkBfKV\\\"]\"")},
     }
         .Check(request);
 
     LegacyScriptPubKeyMan &spk_man = EnsureLegacyScriptPubKeyMan(*pwallet);
 
     auto locked_chain = pwallet->chain().lock();
     LOCK2(pwallet->cs_wallet, spk_man.cs_KeyStore);
 
     std::string label;
     if (!request.params[2].isNull()) {
         label = LabelFromValue(request.params[2]);
     }
 
     int required = request.params[0].get_int();
 
     // Get the public keys
     const UniValue &keys_or_addrs = request.params[1].get_array();
     std::vector<CPubKey> pubkeys;
     for (size_t i = 0; i < keys_or_addrs.size(); ++i) {
         if (IsHex(keys_or_addrs[i].get_str()) &&
             (keys_or_addrs[i].get_str().length() == 66 ||
              keys_or_addrs[i].get_str().length() == 130)) {
             pubkeys.push_back(HexToPubKey(keys_or_addrs[i].get_str()));
         } else {
             pubkeys.push_back(AddrToPubKey(wallet->chainParams, spk_man,
                                            keys_or_addrs[i].get_str()));
         }
     }
 
     OutputType output_type = pwallet->m_default_address_type;
 
     // Construct using pay-to-script-hash:
     CScript inner;
     CTxDestination dest = AddAndGetMultisigDestination(
         required, pubkeys, output_type, spk_man, inner);
     pwallet->SetAddressBook(dest, label, "send");
 
     UniValue result(UniValue::VOBJ);
     result.pushKV("address", EncodeDestination(dest, config));
     result.pushKV("redeemScript", HexStr(inner.begin(), inner.end()));
     return result;
 }
 
 struct tallyitem {
     Amount nAmount{Amount::zero()};
     int nConf{std::numeric_limits<int>::max()};
     std::vector<uint256> txids;
     bool fIsWatchonly{false};
     tallyitem() {}
 };
 
 static UniValue
 ListReceived(const Config &config, interfaces::Chain::Lock &locked_chain,
              CWallet *const pwallet, const UniValue &params, bool by_label)
     EXCLUSIVE_LOCKS_REQUIRED(pwallet->cs_wallet) {
     // Minimum confirmations
     int nMinDepth = 1;
     if (!params[0].isNull()) {
         nMinDepth = params[0].get_int();
     }
 
     // Whether to include empty labels
     bool fIncludeEmpty = false;
     if (!params[1].isNull()) {
         fIncludeEmpty = params[1].get_bool();
     }
 
     isminefilter filter = ISMINE_SPENDABLE;
     if (ParseIncludeWatchonly(params[2], *pwallet)) {
         filter |= ISMINE_WATCH_ONLY;
     }
 
     bool has_filtered_address = false;
     CTxDestination filtered_address = CNoDestination();
     if (!by_label && params.size() > 3) {
         if (!IsValidDestinationString(params[3].get_str(),
                                       pwallet->chainParams)) {
             throw JSONRPCError(RPC_WALLET_ERROR,
                                "address_filter parameter was invalid");
         }
         filtered_address =
             DecodeDestination(params[3].get_str(), pwallet->chainParams);
         has_filtered_address = true;
     }
 
     // Tally
     std::map<CTxDestination, tallyitem> mapTally;
     for (const std::pair<const TxId, CWalletTx> &pairWtx : pwallet->mapWallet) {
         const CWalletTx &wtx = pairWtx.second;
 
         TxValidationState state;
         if (wtx.IsCoinBase() ||
             !locked_chain.contextualCheckTransactionForCurrentBlock(
                 pwallet->chainParams.GetConsensus(), *wtx.tx, state)) {
             continue;
         }
 
         int nDepth = wtx.GetDepthInMainChain();
         if (nDepth < nMinDepth) {
             continue;
         }
 
         for (const CTxOut &txout : wtx.tx->vout) {
             CTxDestination address;
             if (!ExtractDestination(txout.scriptPubKey, address)) {
                 continue;
             }
 
             if (has_filtered_address && !(filtered_address == address)) {
                 continue;
             }
 
             isminefilter mine = pwallet->IsMine(address);
             if (!(mine & filter)) {
                 continue;
             }
 
             tallyitem &item = mapTally[address];
             item.nAmount += txout.nValue;
             item.nConf = std::min(item.nConf, nDepth);
             item.txids.push_back(wtx.GetId());
             if (mine & ISMINE_WATCH_ONLY) {
                 item.fIsWatchonly = true;
             }
         }
     }
 
     // Reply
     UniValue ret(UniValue::VARR);
     std::map<std::string, tallyitem> label_tally;
 
     // Create m_address_book iterator
     // If we aren't filtering, go from begin() to end()
     auto start = pwallet->m_address_book.begin();
     auto end = pwallet->m_address_book.end();
     // If we are filtering, find() the applicable entry
     if (has_filtered_address) {
         start = pwallet->m_address_book.find(filtered_address);
         if (start != end) {
             end = std::next(start);
         }
     }
 
     for (auto item_it = start; item_it != end; ++item_it) {
         if (item_it->second.IsChange()) {
             continue;
         }
         const CTxDestination &address = item_it->first;
         const std::string &label = item_it->second.GetLabel();
         std::map<CTxDestination, tallyitem>::iterator it =
             mapTally.find(address);
         if (it == mapTally.end() && !fIncludeEmpty) {
             continue;
         }
 
         Amount nAmount = Amount::zero();
         int nConf = std::numeric_limits<int>::max();
         bool fIsWatchonly = false;
         if (it != mapTally.end()) {
             nAmount = (*it).second.nAmount;
             nConf = (*it).second.nConf;
             fIsWatchonly = (*it).second.fIsWatchonly;
         }
 
         if (by_label) {
             tallyitem &_item = label_tally[label];
             _item.nAmount += nAmount;
             _item.nConf = std::min(_item.nConf, nConf);
             _item.fIsWatchonly = fIsWatchonly;
         } else {
             UniValue obj(UniValue::VOBJ);
             if (fIsWatchonly) {
                 obj.pushKV("involvesWatchonly", true);
             }
             obj.pushKV("address", EncodeDestination(address, config));
             obj.pushKV("amount", ValueFromAmount(nAmount));
             obj.pushKV("confirmations",
                        (nConf == std::numeric_limits<int>::max() ? 0 : nConf));
             obj.pushKV("label", label);
             UniValue transactions(UniValue::VARR);
             if (it != mapTally.end()) {
                 for (const uint256 &_item : (*it).second.txids) {
                     transactions.push_back(_item.GetHex());
                 }
             }
             obj.pushKV("txids", transactions);
             ret.push_back(obj);
         }
     }
 
     if (by_label) {
         for (const auto &entry : label_tally) {
             Amount nAmount = entry.second.nAmount;
             int nConf = entry.second.nConf;
             UniValue obj(UniValue::VOBJ);
             if (entry.second.fIsWatchonly) {
                 obj.pushKV("involvesWatchonly", true);
             }
             obj.pushKV("amount", ValueFromAmount(nAmount));
             obj.pushKV("confirmations",
                        (nConf == std::numeric_limits<int>::max() ? 0 : nConf));
             obj.pushKV("label", entry.first);
             ret.push_back(obj);
         }
     }
 
     return ret;
 }
 
 static UniValue listreceivedbyaddress(const Config &config,
                                       const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "listreceivedbyaddress",
         "List balances by receiving address.\n",
         {
             {"minconf", RPCArg::Type::NUM, /* default */ "1",
              "The minimum number of confirmations before payments are "
              "included."},
             {"include_empty", RPCArg::Type::BOOL, /* default */ "false",
              "Whether to include addresses that haven't received any "
              "payments."},
             {"include_watchonly", RPCArg::Type::BOOL,
              /* default */ "true for watch-only wallets, otherwise false",
              "Whether to include watch-only addresses (see 'importaddress')."},
             {"address_filter", RPCArg::Type::STR,
              RPCArg::Optional::OMITTED_NAMED_ARG,
              "If present, only return information on this address."},
         },
         RPCResult{
             "[\n"
             "  {\n"
             "    \"involvesWatchonly\" : true,        (bool) Only returns true "
             "if imported addresses were involved in transaction\n"
             "    \"address\" : \"receivingaddress\",  (string) The receiving "
             "address\n"
             "    \"amount\" : x.xxx,                  (numeric) The total "
             "amount in " +
             CURRENCY_UNIT +
             " received by the address\n"
             "    \"confirmations\" : n,               (numeric) The number of "
             "confirmations of the most recent transaction included\n"
             "    \"label\" : \"label\",               (string) The label of "
             "the receiving address. The default label is \"\".\n"
             "    \"txids\": [\n"
             "       \"txid\",                         (string) The ids of "
             "transactions received with the address \n"
             "       ...\n"
             "    ]\n"
             "  }\n"
             "  ,...\n"
             "]\n"},
         RPCExamples{
             HelpExampleCli("listreceivedbyaddress", "") +
             HelpExampleCli("listreceivedbyaddress", "6 true") +
             HelpExampleRpc("listreceivedbyaddress", "6, true, true") +
             HelpExampleRpc(
                 "listreceivedbyaddress",
                 "6, true, true, \"1M72Sfpbz1BPpXFHz9m3CdqATR44Jvaydd\"")},
     }
         .Check(request);
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     return ListReceived(config, *locked_chain, pwallet, request.params, false);
 }
 
 static UniValue listreceivedbylabel(const Config &config,
                                     const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "listreceivedbylabel",
         "List received transactions by label.\n",
         {
             {"minconf", RPCArg::Type::NUM, /* default */ "1",
              "The minimum number of confirmations before payments are "
              "included."},
             {"include_empty", RPCArg::Type::BOOL, /* default */ "false",
              "Whether to include labels that haven't received any payments."},
             {"include_watchonly", RPCArg::Type::BOOL,
              /* default */ "true for watch-only wallets, otherwise false",
              "Whether to include watch-only addresses (see 'importaddress')."},
         },
         RPCResult{"[\n"
                   "  {\n"
                   "    \"involvesWatchonly\" : true,   (bool) Only returns "
                   "true if imported addresses were involved in transaction\n"
                   "    \"amount\" : x.xxx,             (numeric) The total "
                   "amount received by addresses with this label\n"
                   "    \"confirmations\" : n,          (numeric) The number of "
                   "confirmations of the most recent transaction included\n"
                   "    \"label\" : \"label\"           (string) The label of "
                   "the receiving address. The default label is \"\".\n"
                   "  }\n"
                   "  ,...\n"
                   "]\n"},
         RPCExamples{HelpExampleCli("listreceivedbylabel", "") +
                     HelpExampleCli("listreceivedbylabel", "6 true") +
                     HelpExampleRpc("listreceivedbylabel", "6, true, true")},
     }
         .Check(request);
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     return ListReceived(config, *locked_chain, pwallet, request.params, true);
 }
 
 static void MaybePushAddress(UniValue &entry, const CTxDestination &dest) {
     if (IsValidDestination(dest)) {
         entry.pushKV("address", EncodeDestination(dest, GetConfig()));
     }
 }
 
 /**
  * List transactions based on the given criteria.
  *
  * @param  pwallet        The wallet.
  * @param  wtx            The wallet transaction.
  * @param  nMinDepth      The minimum confirmation depth.
  * @param  fLong          Whether to include the JSON version of the
  * transaction.
  * @param  ret            The UniValue into which the result is stored.
  * @param  filter_ismine  The "is mine" filter flags.
  * @param  filter_label   Optional label string to filter incoming transactions.
  */
 static void ListTransactions(interfaces::Chain::Lock &locked_chain,
                              CWallet *const pwallet, const CWalletTx &wtx,
                              int nMinDepth, bool fLong, UniValue &ret,
                              const isminefilter &filter_ismine,
                              const std::string *filter_label)
     EXCLUSIVE_LOCKS_REQUIRED(pwallet->cs_wallet) {
     Amount nFee;
     std::list<COutputEntry> listReceived;
     std::list<COutputEntry> listSent;
 
     wtx.GetAmounts(listReceived, listSent, nFee, filter_ismine);
 
     bool involvesWatchonly = wtx.IsFromMe(ISMINE_WATCH_ONLY);
 
     // Sent
     if (!filter_label) {
         for (const COutputEntry &s : listSent) {
             UniValue entry(UniValue::VOBJ);
             if (involvesWatchonly ||
                 (pwallet->IsMine(s.destination) & ISMINE_WATCH_ONLY)) {
                 entry.pushKV("involvesWatchonly", true);
             }
             MaybePushAddress(entry, s.destination);
             entry.pushKV("category", "send");
             entry.pushKV("amount", ValueFromAmount(-s.amount));
             const auto *address_book_entry =
                 pwallet->FindAddressBookEntry(s.destination);
             if (address_book_entry) {
                 entry.pushKV("label", address_book_entry->GetLabel());
             }
             entry.pushKV("vout", s.vout);
             entry.pushKV("fee", ValueFromAmount(-1 * nFee));
             if (fLong) {
                 WalletTxToJSON(pwallet->chain(), locked_chain, wtx, entry);
             }
             entry.pushKV("abandoned", wtx.isAbandoned());
             ret.push_back(entry);
         }
     }
 
     // Received
     if (listReceived.size() > 0 && wtx.GetDepthInMainChain() >= nMinDepth) {
         for (const COutputEntry &r : listReceived) {
             std::string label;
             const auto *address_book_entry =
                 pwallet->FindAddressBookEntry(r.destination);
             if (address_book_entry) {
                 label = address_book_entry->GetLabel();
             }
             if (filter_label && label != *filter_label) {
                 continue;
             }
             UniValue entry(UniValue::VOBJ);
             if (involvesWatchonly ||
                 (pwallet->IsMine(r.destination) & ISMINE_WATCH_ONLY)) {
                 entry.pushKV("involvesWatchonly", true);
             }
             MaybePushAddress(entry, r.destination);
             if (wtx.IsCoinBase()) {
                 if (wtx.GetDepthInMainChain() < 1) {
                     entry.pushKV("category", "orphan");
                 } else if (wtx.IsImmatureCoinBase()) {
                     entry.pushKV("category", "immature");
                 } else {
                     entry.pushKV("category", "generate");
                 }
             } else {
                 entry.pushKV("category", "receive");
             }
             entry.pushKV("amount", ValueFromAmount(r.amount));
             if (address_book_entry) {
                 entry.pushKV("label", label);
             }
             entry.pushKV("vout", r.vout);
             if (fLong) {
                 WalletTxToJSON(pwallet->chain(), locked_chain, wtx, entry);
             }
             ret.push_back(entry);
         }
     }
 }
 
 static const std::string TransactionDescriptionString() {
     return "    \"confirmations\": n,                        (numeric) The "
            "number of confirmations for the transaction. Negative "
            "confirmations means the\n"
            "                                                       transaction "
            "conflicted that many blocks ago.\n"
            "    \"generated\": xxx,                          (bool) Only "
            "present if transaction only input is a coinbase one.\n"
            "    \"trusted\": xxx,                            (bool) Only "
            "present if we consider transaction to be trusted and so safe to "
            "spend from.\n"
            "    \"blockhash\": \"hashvalue\",                  (string) The "
            "block hash containing the transaction.\n"
            "    \"blockheight\": n,                          (numeric) The "
            "block height containing the transaction.\n"
            "    \"blockindex\": n,                           (numeric) The "
            "index of the transaction in the block that includes it.\n"
            "    \"blocktime\": xxx,                          (numeric) The "
            "block time expressed in " +
            UNIX_EPOCH_TIME +
            ".\n"
            "    \"txid\": \"transactionid\",                   (string) The "
            "transaction id.\n"
            "    \"walletconflicts\": [                       (array) "
            "Conflicting transaction ids.\n"
            "      \"txid\",                                  (string) The "
            "transaction id.\n"
            "      ...\n"
            "    ],\n"
            "    \"time\": xxx,                               (numeric) The "
            "transaction time expressed in " +
            UNIX_EPOCH_TIME +
            ".\n"
            "    \"timereceived\": xxx,                       (numeric) The "
            "time received expressed in " +
            UNIX_EPOCH_TIME +
            ".\n"
            "    \"comment\": \"...\",                          (string) If a "
            "comment is associated with the transaction, only present if not "
            "empty.\n";
 }
 
 UniValue listtransactions(const Config &config, const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "listtransactions",
         "If a label name is provided, this will return only incoming "
         "transactions paying to addresses with the specified label.\n"
         "\nReturns up to 'count' most recent transactions skipping the first "
         "'from' transactions.\n",
         {
             {"label", RPCArg::Type::STR, RPCArg::Optional::OMITTED_NAMED_ARG,
              "If set, should be a valid label name to return only incoming "
              "transactions with the specified label, or \"*\" to disable "
              "filtering and return all transactions."},
             {"count", RPCArg::Type::NUM, /* default */ "10",
              "The number of transactions to return"},
             {"skip", RPCArg::Type::NUM, /* default */ "0",
              "The number of transactions to skip"},
             {"include_watchonly", RPCArg::Type::BOOL,
              /* default */ "true for watch-only wallets, otherwise false",
              "Include transactions to watch-only addresses (see "
              "'importaddress')"},
         },
         RPCResult{
             "[\n"
             "  {\n"
             "    \"involvesWatchonly\": xxx, (bool) Only returns true if "
             "imported addresses were involved in transaction.\n"
             "    \"address\":\"address\",      (string) The bitcoin address of "
             "the transaction.\n"
             "    \"category\":               (string) The transaction "
             "category.\n"
             "                \"send\"                  Transactions sent.\n"
             "                \"receive\"               Non-coinbase "
             "transactions received.\n"
             "                \"generate\"              Coinbase transactions "
             "received with more than 100 confirmations.\n"
             "                \"immature\"              Coinbase transactions "
             "received with 100 or fewer confirmations.\n"
             "                \"orphan\"                Orphaned coinbase "
             "transactions received.\n"
             "    \"amount\": x.xxx,          (numeric) The amount in " +
             CURRENCY_UNIT +
             ". This is negative for the 'send' category, and is positive\n"
             "                                        for all other categories\n"
             "    \"label\": \"label\",         (string) A comment for the "
             "address/transaction, if any\n"
             "    \"vout\": n,                (numeric) the vout value\n"
             "    \"fee\": x.xxx,             (numeric) The amount of the fee "
             "in " +
             CURRENCY_UNIT +
             ". This is negative and only available for the \n"
             "                                         'send' category of "
             "transactions.\n" +
             TransactionDescriptionString() +
             "    \"abandoned\": xxx          (bool) 'true' if the transaction "
             "has been abandoned (inputs are respendable). Only available for "
             "the \n"
             "                                         'send' category of "
             "transactions.\n"
             "  }\n"
             "]\n"},
         RPCExamples{"\nList the most recent 10 transactions in the systems\n" +
                     HelpExampleCli("listtransactions", "") +
                     "\nList transactions 100 to 120\n" +
                     HelpExampleCli("listtransactions", "\"*\" 20 100") +
                     "\nAs a JSON-RPC call\n" +
                     HelpExampleRpc("listtransactions", "\"*\", 20, 100")},
     }
         .Check(request);
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
     const std::string *filter_label = nullptr;
     if (!request.params[0].isNull() && request.params[0].get_str() != "*") {
         filter_label = &request.params[0].get_str();
         if (filter_label->empty()) {
             throw JSONRPCError(
                 RPC_INVALID_PARAMETER,
                 "Label argument must be a valid label name or \"*\".");
         }
     }
     int nCount = 10;
     if (!request.params[1].isNull()) {
         nCount = request.params[1].get_int();
     }
 
     int nFrom = 0;
     if (!request.params[2].isNull()) {
         nFrom = request.params[2].get_int();
     }
 
     isminefilter filter = ISMINE_SPENDABLE;
     if (ParseIncludeWatchonly(request.params[3], *pwallet)) {
         filter |= ISMINE_WATCH_ONLY;
     }
 
     if (nCount < 0) {
         throw JSONRPCError(RPC_INVALID_PARAMETER, "Negative count");
     }
     if (nFrom < 0) {
         throw JSONRPCError(RPC_INVALID_PARAMETER, "Negative from");
     }
     UniValue ret(UniValue::VARR);
 
     {
         auto locked_chain = pwallet->chain().lock();
         LOCK(pwallet->cs_wallet);
 
         const CWallet::TxItems &txOrdered = pwallet->wtxOrdered;
 
         // iterate backwards until we have nCount items to return:
         for (CWallet::TxItems::const_reverse_iterator it = txOrdered.rbegin();
              it != txOrdered.rend(); ++it) {
             CWalletTx *const pwtx = (*it).second;
             ListTransactions(*locked_chain, pwallet, *pwtx, 0, true, ret,
                              filter, filter_label);
             if (int(ret.size()) >= (nCount + nFrom)) {
                 break;
             }
         }
     }
 
     // ret is newest to oldest
 
     if (nFrom > (int)ret.size()) {
         nFrom = ret.size();
     }
     if ((nFrom + nCount) > (int)ret.size()) {
         nCount = ret.size() - nFrom;
     }
 
     const std::vector<UniValue> &txs = ret.getValues();
     UniValue result{UniValue::VARR};
     // Return oldest to newest
     result.push_backV({txs.rend() - nFrom - nCount, txs.rend() - nFrom});
     return result;
 }
 
 static UniValue listsinceblock(const Config &config,
                                const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "listsinceblock",
         "Get all transactions in blocks since block [blockhash], or all "
         "transactions if omitted.\n"
         "If \"blockhash\" is no longer a part of the main chain, transactions "
         "from the fork point onward are included.\n"
         "Additionally, if include_removed is set, transactions affecting the "
         "wallet which were removed are returned in the \"removed\" array.\n",
         {
             {"blockhash", RPCArg::Type::STR,
              RPCArg::Optional::OMITTED_NAMED_ARG,
              "If set, the block hash to list transactions since, otherwise "
              "list all transactions."},
             {"target_confirmations", RPCArg::Type::NUM, /* default */ "1",
              "Return the nth block hash from the main chain. e.g. 1 would mean "
              "the best block hash. Note: this is not used as a filter, but "
              "only affects [lastblock] in the return value"},
             {"include_watchonly", RPCArg::Type::BOOL,
              /* default */ "true for watch-only wallets, otherwise false",
              "Include transactions to watch-only addresses (see "
              "'importaddress')"},
             {"include_removed", RPCArg::Type::BOOL, /* default */ "true",
              "Show transactions that were removed due to a reorg in the "
              "\"removed\" array\n"
              "                                                           (not "
              "guaranteed to work on pruned nodes)"},
         },
         RPCResult{
             "{\n"
             "  \"transactions\": [\n"
             "    \"involvesWatchonly\": xxx, (bool) Only returns true if "
             "imported addresses were involved in transaction.\n"
             "    \"address\":\"address\",    (string) The bitcoin address of "
             "the transaction.\n"
             "    \"category\":               (string) The transaction "
             "category.\n"
             "                \"send\"                  Transactions sent.\n"
             "                \"receive\"               Non-coinbase "
             "transactions received.\n"
             "                \"generate\"              Coinbase transactions "
             "received with more than 100 confirmations.\n"
             "                \"immature\"              Coinbase transactions "
             "received with 100 or fewer confirmations.\n"
             "                \"orphan\"                Orphaned coinbase "
             "transactions received.\n"
             "    \"amount\": x.xxx,          (numeric) The amount in " +
             CURRENCY_UNIT +
             ". This is negative for the 'send' category, and is positive\n"
             "                                         for all other "
             "categories\n"
             "    \"vout\" : n,               (numeric) the vout value\n"
             "    \"fee\": x.xxx,             (numeric) The amount of the fee "
             "in " +
             CURRENCY_UNIT +
             ". This is negative and only available for the 'send' category of "
             "transactions.\n" +
             TransactionDescriptionString() +
             "    \"abandoned\": xxx,         (bool) 'true' if the transaction "
             "has been abandoned (inputs are respendable). Only available for "
             "the 'send' category of transactions.\n"
             "    \"comment\": \"...\",       (string) If a comment is "
             "associated with the transaction.\n"
             "    \"label\" : \"label\"       (string) A comment for the "
             "address/transaction, if any\n"
             "    \"to\": \"...\",            (string) If a comment to is "
             "associated with the transaction.\n"
             "  ],\n"
             "  \"removed\": [\n"
             "    <structure is the same as \"transactions\" above, only "
             "present if include_removed=true>\n"
             "    Note: transactions that were re-added in the active chain "
             "will appear as-is in this array, and may thus have a positive "
             "confirmation count.\n"
             "  ],\n"
             "  \"lastblock\": \"lastblockhash\"     (string) The hash of the "
             "block (target_confirmations-1) from the best block on the main "
             "chain. This is typically used to feed back into listsinceblock "
             "the next time you call it. So you would generally use a "
             "target_confirmations of say 6, so you will be continually "
             "re-notified of transactions until they've reached 6 confirmations "
             "plus any new ones\n"
             "}\n"},
         RPCExamples{HelpExampleCli("listsinceblock", "") +
                     HelpExampleCli("listsinceblock",
                                    "\"000000000000000bacf66f7497b7dc45ef753ee9a"
                                    "7d38571037cdb1a57f663ad\" 6") +
                     HelpExampleRpc("listsinceblock",
                                    "\"000000000000000bacf66f7497b7dc45ef753ee9a"
                                    "7d38571037cdb1a57f663ad\", 6")},
     }
         .Check(request);
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     // The way the 'height' is initialized is just a workaround for the gcc bug
     // #47679 since version 4.6.0. Height of the specified block or the common
     // ancestor, if the block provided was in a deactivated chain.
     Optional<int> height = MakeOptional(false, int());
 
     // Height of the specified block, even if it's in a deactivated chain.
     Optional<int> altheight;
     int target_confirms = 1;
     isminefilter filter = ISMINE_SPENDABLE;
 
     BlockHash blockId;
     if (!request.params[0].isNull() && !request.params[0].get_str().empty()) {
         blockId = BlockHash(ParseHashV(request.params[0], "blockhash"));
         height = locked_chain->findFork(blockId, &altheight);
         if (!height) {
             throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found");
         }
     }
 
     if (!request.params[1].isNull()) {
         target_confirms = request.params[1].get_int();
 
         if (target_confirms < 1) {
             throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid parameter");
         }
     }
 
     if (ParseIncludeWatchonly(request.params[2], *pwallet)) {
         filter |= ISMINE_WATCH_ONLY;
     }
 
     bool include_removed =
         (request.params[3].isNull() || request.params[3].get_bool());
 
     const Optional<int> tip_height = locked_chain->getHeight();
     int depth = tip_height && height ? (1 + *tip_height - *height) : -1;
 
     UniValue transactions(UniValue::VARR);
 
     for (const std::pair<const TxId, CWalletTx> &pairWtx : pwallet->mapWallet) {
         CWalletTx tx = pairWtx.second;
 
         if (depth == -1 || tx.GetDepthInMainChain() < depth) {
             ListTransactions(*locked_chain, pwallet, tx, 0, true, transactions,
                              filter, nullptr /* filter_label */);
         }
     }
 
     // when a reorg'd block is requested, we also list any relevant transactions
     // in the blocks of the chain that was detached
     UniValue removed(UniValue::VARR);
     while (include_removed && altheight && *altheight > *height) {
         CBlock block;
-        if (!pwallet->chain().findBlock(blockId, &block) || block.IsNull()) {
+        if (!pwallet->chain().findBlock(blockId, FoundBlock().data(block)) ||
+            block.IsNull()) {
             throw JSONRPCError(RPC_INTERNAL_ERROR,
                                "Can't read block from disk");
         }
         for (const CTransactionRef &tx : block.vtx) {
             auto it = pwallet->mapWallet.find(tx->GetId());
             if (it != pwallet->mapWallet.end()) {
                 // We want all transactions regardless of confirmation count to
                 // appear here, even negative confirmation ones, hence the big
                 // negative.
                 ListTransactions(*locked_chain, pwallet, it->second, -100000000,
                                  true, removed, filter,
                                  nullptr /* filter_label */);
             }
         }
         blockId = block.hashPrevBlock;
         --*altheight;
     }
 
     int last_height = tip_height ? *tip_height + 1 - target_confirms : -1;
     BlockHash lastblock = last_height >= 0
                               ? locked_chain->getBlockHash(last_height)
                               : BlockHash();
 
     UniValue ret(UniValue::VOBJ);
     ret.pushKV("transactions", transactions);
     if (include_removed) {
         ret.pushKV("removed", removed);
     }
     ret.pushKV("lastblock", lastblock.GetHex());
 
     return ret;
 }
 
 static UniValue gettransaction(const Config &config,
                                const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "gettransaction",
         "Get detailed information about in-wallet transaction <txid>\n",
         {
             {"txid", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The transaction id"},
             {"include_watchonly", RPCArg::Type::BOOL,
              /* default */ "true for watch-only wallets, otherwise false",
              "Whether to include watch-only addresses in balance calculation "
              "and details[]"},
             {"verbose", RPCArg::Type::BOOL, /* default */ "false",
              "Whether to include a `decoded` field containing the decoded "
              "transaction (equivalent to RPC decoderawtransaction)"},
         },
         RPCResult{
             "{\n"
             "    \"amount\" : x.xxx,        (numeric) The transaction amount "
             "in " +
             CURRENCY_UNIT +
             "\n"
             "    \"fee\": x.xxx,            (numeric) The amount of the fee "
             "in " +
             CURRENCY_UNIT +
             ". This is negative and only available for the \n"
             "                              'send' category of transactions.\n" +
             TransactionDescriptionString() +
             +"    \"details\" : [\n"
              "      {\n"
              "        \"involvesWatchonly\": xxx,         (bool) Only returns "
              "true if imported addresses were involved in transaction.\n"
              "        \"address\" : \"address\",          (string) The bitcoin "
              "address involved in the transaction\n"
              "        \"category\" :                      (string) The "
              "transaction category.\n"
              "                     \"send\"                  Transactions "
              "sent.\n"
              "                     \"receive\"               Non-coinbase "
              "transactions received.\n"
              "                     \"generate\"              Coinbase "
              "transactions received with more than 100 confirmations.\n"
              "                     \"immature\"              Coinbase "
              "transactions received with 100 or fewer confirmations.\n"
              "                     \"orphan\"                Orphaned coinbase "
              "transactions received.\n"
              "        \"amount\" : x.xxx,                 (numeric) The amount "
              "in " +
             CURRENCY_UNIT +
             "\n"
             "        \"label\" : \"label\",              (string) A comment "
             "for the address/transaction, if any\n"
             "        \"vout\" : n,                       (numeric) the vout "
             "value\n"
             "        \"fee\": x.xxx,                     (numeric) The amount "
             "of the fee in " +
             CURRENCY_UNIT +
             ". This is negative and only available for the \n"
             "                                           'send' category of "
             "transactions.\n"
             "        \"abandoned\": xxx                  (bool) 'true' if the "
             "transaction has been abandoned (inputs are respendable). Only "
             "available for the \n"
             "                                           'send' category of "
             "transactions.\n"
             "      }\n"
             "      ,...\n"
             "    ],\n"
             "    \"hex\" : \"data\"         (string) Raw data for transaction\n"
             "    \"decoded\" : transaction         (json object) Optional, the "
             "decoded transaction (only present when `verbose` is passed), "
             "equivalent to the\n"
             "                                                  RPC "
             "decoderawtransaction method, or the RPC getrawtransaction method "
             "when `verbose` is passed.\n"
             "}\n"},
         RPCExamples{HelpExampleCli("gettransaction",
                                    "\"1075db55d416d3ca199f55b6084e2115b9345e16c"
                                    "5cf302fc80e9d5fbf5d48d\"") +
                     HelpExampleCli("gettransaction",
                                    "\"1075db55d416d3ca199f55b6084e2115b9345e16c"
                                    "5cf302fc80e9d5fbf5d48d\" true") +
                     HelpExampleCli("gettransaction",
                                    "\"1075db55d416d3ca199f55b6084e2115b9345e16c"
                                    "5cf302fc80e9d5fbf5d48d\" false true") +
                     HelpExampleRpc("gettransaction",
                                    "\"1075db55d416d3ca199f55b6084e2115b9345e16c"
                                    "5cf302fc80e9d5fbf5d48d\"")},
     }
         .Check(request);
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     TxId txid(ParseHashV(request.params[0], "txid"));
 
     isminefilter filter = ISMINE_SPENDABLE;
     if (ParseIncludeWatchonly(request.params[1], *pwallet)) {
         filter |= ISMINE_WATCH_ONLY;
     }
 
     bool verbose =
         request.params[2].isNull() ? false : request.params[2].get_bool();
 
     UniValue entry(UniValue::VOBJ);
     auto it = pwallet->mapWallet.find(txid);
     if (it == pwallet->mapWallet.end()) {
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY,
                            "Invalid or non-wallet transaction id");
     }
     const CWalletTx &wtx = it->second;
 
     Amount nCredit = wtx.GetCredit(filter);
     Amount nDebit = wtx.GetDebit(filter);
     Amount nNet = nCredit - nDebit;
     Amount nFee = (wtx.IsFromMe(filter) ? wtx.tx->GetValueOut() - nDebit
                                         : Amount::zero());
 
     entry.pushKV("amount", ValueFromAmount(nNet - nFee));
     if (wtx.IsFromMe(filter)) {
         entry.pushKV("fee", ValueFromAmount(nFee));
     }
 
     WalletTxToJSON(pwallet->chain(), *locked_chain, wtx, entry);
 
     UniValue details(UniValue::VARR);
     ListTransactions(*locked_chain, pwallet, wtx, 0, false, details, filter,
                      nullptr /* filter_label */);
     entry.pushKV("details", details);
 
     std::string strHex =
         EncodeHexTx(*wtx.tx, pwallet->chain().rpcSerializationFlags());
     entry.pushKV("hex", strHex);
 
     if (verbose) {
         UniValue decoded(UniValue::VOBJ);
         TxToUniv(*wtx.tx, uint256(), decoded, false);
         entry.pushKV("decoded", decoded);
     }
 
     return entry;
 }
 
 static UniValue abandontransaction(const Config &config,
                                    const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "abandontransaction",
         "Mark in-wallet transaction <txid> as abandoned\n"
         "This will mark this transaction and all its in-wallet descendants as "
         "abandoned which will allow\n"
         "for their inputs to be respent.  It can be used to replace \"stuck\" "
         "or evicted transactions.\n"
         "It only works on transactions which are not included in a block and "
         "are not currently in the mempool.\n"
         "It has no effect on transactions which are already abandoned.\n",
         {
             {"txid", RPCArg::Type::STR_HEX, RPCArg::Optional::NO,
              "The transaction id"},
         },
         RPCResults{},
         RPCExamples{HelpExampleCli("abandontransaction",
                                    "\"1075db55d416d3ca199f55b6084e2115b9345e16c"
                                    "5cf302fc80e9d5fbf5d48d\"") +
                     HelpExampleRpc("abandontransaction",
                                    "\"1075db55d416d3ca199f55b6084e2115b9345e16c"
                                    "5cf302fc80e9d5fbf5d48d\"")},
     }
         .Check(request);
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     TxId txid(ParseHashV(request.params[0], "txid"));
 
     if (!pwallet->mapWallet.count(txid)) {
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY,
                            "Invalid or non-wallet transaction id");
     }
 
     if (!pwallet->AbandonTransaction(txid)) {
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY,
                            "Transaction not eligible for abandonment");
     }
 
     return NullUniValue;
 }
 
 static UniValue backupwallet(const Config &config,
                              const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "backupwallet",
         "Safely copies current wallet file to destination, which can be a "
         "directory or a path with filename.\n",
         {
             {"destination", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The destination directory or file"},
         },
         RPCResults{},
         RPCExamples{HelpExampleCli("backupwallet", "\"backup.dat\"") +
                     HelpExampleRpc("backupwallet", "\"backup.dat\"")},
     }
         .Check(request);
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     std::string strDest = request.params[0].get_str();
     if (!pwallet->BackupWallet(strDest)) {
         throw JSONRPCError(RPC_WALLET_ERROR, "Error: Wallet backup failed!");
     }
 
     return NullUniValue;
 }
 
 static UniValue keypoolrefill(const Config &config,
                               const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "keypoolrefill",
         "Fills the keypool." + HelpRequiringPassphrase(pwallet) + "\n",
         {
             {"newsize", RPCArg::Type::NUM, /* default */ "100",
              "The new keypool size"},
         },
         RPCResults{},
         RPCExamples{HelpExampleCli("keypoolrefill", "") +
                     HelpExampleRpc("keypoolrefill", "")},
     }
         .Check(request);
 
     if (pwallet->IsWalletFlagSet(WALLET_FLAG_DISABLE_PRIVATE_KEYS)) {
         throw JSONRPCError(RPC_WALLET_ERROR,
                            "Error: Private keys are disabled for this wallet");
     }
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     // 0 is interpreted by TopUpKeyPool() as the default keypool size given by
     // -keypool
     unsigned int kpSize = 0;
     if (!request.params[0].isNull()) {
         if (request.params[0].get_int() < 0) {
             throw JSONRPCError(RPC_INVALID_PARAMETER,
                                "Invalid parameter, expected valid size.");
         }
         kpSize = (unsigned int)request.params[0].get_int();
     }
 
     EnsureWalletIsUnlocked(pwallet);
     pwallet->TopUpKeyPool(kpSize);
 
     if (pwallet->GetKeyPoolSize() < kpSize) {
         throw JSONRPCError(RPC_WALLET_ERROR, "Error refreshing keypool.");
     }
 
     return NullUniValue;
 }
 
 static UniValue walletpassphrase(const Config &config,
                                  const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "walletpassphrase",
         "Stores the wallet decryption key in memory for 'timeout' seconds.\n"
         "This is needed prior to performing transactions related to private "
         "keys such as sending bitcoins\n"
         "\nNote:\n"
         "Issuing the walletpassphrase command while the wallet is already "
         "unlocked will set a new unlock\n"
         "time that overrides the old one.\n",
         {
             {"passphrase", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The wallet passphrase"},
             {"timeout", RPCArg::Type::NUM, RPCArg::Optional::NO,
              "The time to keep the decryption key in seconds; capped at "
              "100000000 (~3 years)."},
         },
         RPCResults{},
         RPCExamples{
             "\nUnlock the wallet for 60 seconds\n" +
             HelpExampleCli("walletpassphrase", "\"my pass phrase\" 60") +
             "\nLock the wallet again (before 60 seconds)\n" +
             HelpExampleCli("walletlock", "") + "\nAs a JSON-RPC call\n" +
             HelpExampleRpc("walletpassphrase", "\"my pass phrase\", 60")},
     }
         .Check(request);
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     if (!pwallet->IsCrypted()) {
         throw JSONRPCError(RPC_WALLET_WRONG_ENC_STATE,
                            "Error: running with an unencrypted wallet, but "
                            "walletpassphrase was called.");
     }
 
     // Note that the walletpassphrase is stored in request.params[0] which is
     // not mlock()ed
     SecureString strWalletPass;
     strWalletPass.reserve(100);
     // TODO: get rid of this .c_str() by implementing
     // SecureString::operator=(std::string)
     // Alternately, find a way to make request.params[0] mlock()'d to begin
     // with.
     strWalletPass = request.params[0].get_str().c_str();
 
     // Get the timeout
     int64_t nSleepTime = request.params[1].get_int64();
     // Timeout cannot be negative, otherwise it will relock immediately
     if (nSleepTime < 0) {
         throw JSONRPCError(RPC_INVALID_PARAMETER,
                            "Timeout cannot be negative.");
     }
     // Clamp timeout
     // larger values trigger a macos/libevent bug?
     constexpr int64_t MAX_SLEEP_TIME = 100000000;
     if (nSleepTime > MAX_SLEEP_TIME) {
         nSleepTime = MAX_SLEEP_TIME;
     }
 
     if (strWalletPass.empty()) {
         throw JSONRPCError(RPC_INVALID_PARAMETER,
                            "passphrase can not be empty");
     }
 
     if (!pwallet->Unlock(strWalletPass)) {
         throw JSONRPCError(
             RPC_WALLET_PASSPHRASE_INCORRECT,
             "Error: The wallet passphrase entered was incorrect.");
     }
 
     pwallet->TopUpKeyPool();
 
     pwallet->nRelockTime = GetTime() + nSleepTime;
 
     // Keep a weak pointer to the wallet so that it is possible to unload the
     // wallet before the following callback is called. If a valid shared pointer
     // is acquired in the callback then the wallet is still loaded.
     std::weak_ptr<CWallet> weak_wallet = wallet;
     pwallet->chain().rpcRunLater(
         strprintf("lockwallet(%s)", pwallet->GetName()),
         [weak_wallet] {
             if (auto shared_wallet = weak_wallet.lock()) {
                 LOCK(shared_wallet->cs_wallet);
                 shared_wallet->Lock();
                 shared_wallet->nRelockTime = 0;
             }
         },
         nSleepTime);
 
     return NullUniValue;
 }
 
 static UniValue walletpassphrasechange(const Config &config,
                                        const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "walletpassphrasechange",
         "Changes the wallet passphrase from 'oldpassphrase' to "
         "'newpassphrase'.\n",
         {
             {"oldpassphrase", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The current passphrase"},
             {"newpassphrase", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The new passphrase"},
         },
         RPCResults{},
         RPCExamples{HelpExampleCli("walletpassphrasechange",
                                    "\"old one\" \"new one\"") +
                     HelpExampleRpc("walletpassphrasechange",
                                    "\"old one\", \"new one\"")},
     }
         .Check(request);
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     if (!pwallet->IsCrypted()) {
         throw JSONRPCError(RPC_WALLET_WRONG_ENC_STATE,
                            "Error: running with an unencrypted wallet, but "
                            "walletpassphrasechange was called.");
     }
 
     // TODO: get rid of these .c_str() calls by implementing
     // SecureString::operator=(std::string)
     // Alternately, find a way to make request.params[0] mlock()'d to begin
     // with.
     SecureString strOldWalletPass;
     strOldWalletPass.reserve(100);
     strOldWalletPass = request.params[0].get_str().c_str();
 
     SecureString strNewWalletPass;
     strNewWalletPass.reserve(100);
     strNewWalletPass = request.params[1].get_str().c_str();
 
     if (strOldWalletPass.empty() || strNewWalletPass.empty()) {
         throw JSONRPCError(RPC_INVALID_PARAMETER,
                            "passphrase can not be empty");
     }
 
     if (!pwallet->ChangeWalletPassphrase(strOldWalletPass, strNewWalletPass)) {
         throw JSONRPCError(
             RPC_WALLET_PASSPHRASE_INCORRECT,
             "Error: The wallet passphrase entered was incorrect.");
     }
 
     return NullUniValue;
 }
 
 static UniValue walletlock(const Config &config,
                            const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "walletlock",
         "Removes the wallet encryption key from memory, locking the wallet.\n"
         "After calling this method, you will need to call walletpassphrase "
         "again\n"
         "before being able to call any methods which require the wallet to be "
         "unlocked.\n",
         {},
         RPCResults{},
         RPCExamples{
             "\nSet the passphrase for 2 minutes to perform a transaction\n" +
             HelpExampleCli("walletpassphrase", "\"my pass phrase\" 120") +
             "\nPerform a send (requires passphrase set)\n" +
             HelpExampleCli("sendtoaddress",
                            "\"1M72Sfpbz1BPpXFHz9m3CdqATR44Jvaydd\" 1.0") +
             "\nClear the passphrase since we are done before 2 minutes is "
             "up\n" +
             HelpExampleCli("walletlock", "") + "\nAs a JSON-RPC call\n" +
             HelpExampleRpc("walletlock", "")},
     }
         .Check(request);
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     if (!pwallet->IsCrypted()) {
         throw JSONRPCError(RPC_WALLET_WRONG_ENC_STATE,
                            "Error: running with an unencrypted wallet, but "
                            "walletlock was called.");
     }
 
     pwallet->Lock();
     pwallet->nRelockTime = 0;
 
     return NullUniValue;
 }
 
 static UniValue encryptwallet(const Config &config,
                               const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "encryptwallet",
         "Encrypts the wallet with 'passphrase'. This is for first time "
         "encryption.\n"
         "After this, any calls that interact with private keys such as sending "
         "or signing \n"
         "will require the passphrase to be set prior the making these calls.\n"
         "Use the walletpassphrase call for this, and then walletlock call.\n"
         "If the wallet is already encrypted, use the walletpassphrasechange "
         "call.\n",
         {
             {"passphrase", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The pass phrase to encrypt the wallet with. It must be at least "
              "1 character, but should be long."},
         },
         RPCResults{},
         RPCExamples{
             "\nEncrypt your wallet\n" +
             HelpExampleCli("encryptwallet", "\"my pass phrase\"") +
             "\nNow set the passphrase to use the wallet, such as for signing "
             "or sending bitcoin\n" +
             HelpExampleCli("walletpassphrase", "\"my pass phrase\"") +
             "\nNow we can do something like sign\n" +
             HelpExampleCli("signmessage", "\"address\" \"test message\"") +
             "\nNow lock the wallet again by removing the passphrase\n" +
             HelpExampleCli("walletlock", "") + "\nAs a JSON-RPC call\n" +
             HelpExampleRpc("encryptwallet", "\"my pass phrase\"")},
     }
         .Check(request);
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     if (pwallet->IsWalletFlagSet(WALLET_FLAG_DISABLE_PRIVATE_KEYS)) {
         throw JSONRPCError(
             RPC_WALLET_ENCRYPTION_FAILED,
             "Error: wallet does not contain private keys, nothing to encrypt.");
     }
 
     if (pwallet->IsCrypted()) {
         throw JSONRPCError(RPC_WALLET_WRONG_ENC_STATE,
                            "Error: running with an encrypted wallet, but "
                            "encryptwallet was called.");
     }
 
     // TODO: get rid of this .c_str() by implementing
     // SecureString::operator=(std::string)
     // Alternately, find a way to make request.params[0] mlock()'d to begin
     // with.
     SecureString strWalletPass;
     strWalletPass.reserve(100);
     strWalletPass = request.params[0].get_str().c_str();
 
     if (strWalletPass.empty()) {
         throw JSONRPCError(RPC_INVALID_PARAMETER,
                            "passphrase can not be empty");
     }
 
     if (!pwallet->EncryptWallet(strWalletPass)) {
         throw JSONRPCError(RPC_WALLET_ENCRYPTION_FAILED,
                            "Error: Failed to encrypt the wallet.");
     }
 
     return "wallet encrypted; The keypool has been flushed and a new HD seed "
            "was generated (if you are using HD). You need to make a new "
            "backup.";
 }
 
 static UniValue lockunspent(const Config &config,
                             const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "lockunspent",
         "Updates list of temporarily unspendable outputs.\n"
         "Temporarily lock (unlock=false) or unlock (unlock=true) specified "
         "transaction outputs.\n"
         "If no transaction outputs are specified when unlocking then all "
         "current locked transaction outputs are unlocked.\n"
         "A locked transaction output will not be chosen by automatic coin "
         "selection, when spending bitcoins.\n"
         "Locks are stored in memory only. Nodes start with zero locked "
         "outputs, and the locked output list\n"
         "is always cleared (by virtue of process exit) when a node stops or "
         "fails.\n"
         "Also see the listunspent call\n",
         {
             {"unlock", RPCArg::Type::BOOL, RPCArg::Optional::NO,
              "Whether to unlock (true) or lock (false) the specified "
              "transactions"},
             {
                 "transactions",
                 RPCArg::Type::ARR,
                 /* default */ "empty array",
                 "A json array of objects. Each object the txid (string) vout "
                 "(numeric).",
                 {
                     {
                         "",
                         RPCArg::Type::OBJ,
                         RPCArg::Optional::OMITTED,
                         "",
                         {
                             {"txid", RPCArg::Type::STR_HEX,
                              RPCArg::Optional::NO, "The transaction id"},
                             {"vout", RPCArg::Type::NUM, RPCArg::Optional::NO,
                              "The output number"},
                         },
                     },
                 },
             },
         },
         RPCResult{"true|false    (boolean) Whether the command was successful "
                   "or not\n"},
         RPCExamples{
             "\nList the unspent transactions\n" +
             HelpExampleCli("listunspent", "") +
             "\nLock an unspent transaction\n" +
             HelpExampleCli("lockunspent", "false "
                                           "\"[{\\\"txid\\\":"
                                           "\\\"a08e6907dbbd3d809776dbfc5d82e371"
                                           "b764ed838b5655e72f463568df1aadf0\\\""
                                           ",\\\"vout\\\":1}]\"") +
             "\nList the locked transactions\n" +
             HelpExampleCli("listlockunspent", "") +
             "\nUnlock the transaction again\n" +
             HelpExampleCli("lockunspent", "true "
                                           "\"[{\\\"txid\\\":"
                                           "\\\"a08e6907dbbd3d809776dbfc5d82e371"
                                           "b764ed838b5655e72f463568df1aadf0\\\""
                                           ",\\\"vout\\\":1}]\"") +
             "\nAs a JSON-RPC call\n" +
             HelpExampleRpc("lockunspent", "false, "
                                           "\"[{\\\"txid\\\":"
                                           "\\\"a08e6907dbbd3d809776dbfc5d82e371"
                                           "b764ed838b5655e72f463568df1aadf0\\\""
                                           ",\\\"vout\\\":1}]\"")},
     }
         .Check(request);
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     RPCTypeCheckArgument(request.params[0], UniValue::VBOOL);
 
     bool fUnlock = request.params[0].get_bool();
 
     if (request.params[1].isNull()) {
         if (fUnlock) {
             pwallet->UnlockAllCoins();
         }
         return true;
     }
 
     RPCTypeCheckArgument(request.params[1], UniValue::VARR);
 
     const UniValue &output_params = request.params[1];
 
     // Create and validate the COutPoints first.
 
     std::vector<COutPoint> outputs;
     outputs.reserve(output_params.size());
 
     for (size_t idx = 0; idx < output_params.size(); idx++) {
         const UniValue &o = output_params[idx].get_obj();
 
         RPCTypeCheckObj(o, {
                                {"txid", UniValueType(UniValue::VSTR)},
                                {"vout", UniValueType(UniValue::VNUM)},
                            });
 
         const int nOutput = find_value(o, "vout").get_int();
         if (nOutput < 0) {
             throw JSONRPCError(RPC_INVALID_PARAMETER,
                                "Invalid parameter, vout must be positive");
         }
 
         const TxId txid(ParseHashO(o, "txid"));
         const auto it = pwallet->mapWallet.find(txid);
         if (it == pwallet->mapWallet.end()) {
             throw JSONRPCError(RPC_INVALID_PARAMETER,
                                "Invalid parameter, unknown transaction");
         }
 
         const COutPoint output(txid, nOutput);
         const CWalletTx &trans = it->second;
         if (output.GetN() >= trans.tx->vout.size()) {
             throw JSONRPCError(RPC_INVALID_PARAMETER,
                                "Invalid parameter, vout index out of bounds");
         }
 
         if (pwallet->IsSpent(output)) {
             throw JSONRPCError(RPC_INVALID_PARAMETER,
                                "Invalid parameter, expected unspent output");
         }
 
         const bool is_locked = pwallet->IsLockedCoin(output);
         if (fUnlock && !is_locked) {
             throw JSONRPCError(RPC_INVALID_PARAMETER,
                                "Invalid parameter, expected locked output");
         }
 
         if (!fUnlock && is_locked) {
             throw JSONRPCError(RPC_INVALID_PARAMETER,
                                "Invalid parameter, output already locked");
         }
 
         outputs.push_back(output);
     }
 
     // Atomically set (un)locked status for the outputs.
     for (const COutPoint &output : outputs) {
         if (fUnlock) {
             pwallet->UnlockCoin(output);
         } else {
             pwallet->LockCoin(output);
         }
     }
 
     return true;
 }
 
 static UniValue listlockunspent(const Config &config,
                                 const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "listlockunspent",
         "Returns list of temporarily unspendable outputs.\n"
         "See the lockunspent call to lock and unlock transactions for "
         "spending.\n",
         {},
         RPCResult{
             "[\n"
             "  {\n"
             "    \"txid\" : \"transactionid\",     (string) The transaction id "
             "locked\n"
             "    \"vout\" : n                      (numeric) The vout value\n"
             "  }\n"
             "  ,...\n"
             "]\n"},
         RPCExamples{
             "\nList the unspent transactions\n" +
             HelpExampleCli("listunspent", "") +
             "\nLock an unspent transaction\n" +
             HelpExampleCli("lockunspent", "false "
                                           "\"[{\\\"txid\\\":"
                                           "\\\"a08e6907dbbd3d809776dbfc5d82e371"
                                           "b764ed838b5655e72f463568df1aadf0\\\""
                                           ",\\\"vout\\\":1}]\"") +
             "\nList the locked transactions\n" +
             HelpExampleCli("listlockunspent", "") +
             "\nUnlock the transaction again\n" +
             HelpExampleCli("lockunspent", "true "
                                           "\"[{\\\"txid\\\":"
                                           "\\\"a08e6907dbbd3d809776dbfc5d82e371"
                                           "b764ed838b5655e72f463568df1aadf0\\\""
                                           ",\\\"vout\\\":1}]\"") +
             "\nAs a JSON-RPC call\n" + HelpExampleRpc("listlockunspent", "")},
     }
         .Check(request);
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     std::vector<COutPoint> vOutpts;
     pwallet->ListLockedCoins(vOutpts);
 
     UniValue ret(UniValue::VARR);
 
     for (const COutPoint &output : vOutpts) {
         UniValue o(UniValue::VOBJ);
 
         o.pushKV("txid", output.GetTxId().GetHex());
         o.pushKV("vout", int(output.GetN()));
         ret.push_back(o);
     }
 
     return ret;
 }
 
 static UniValue settxfee(const Config &config, const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "settxfee",
         "Set the transaction fee per kB for this wallet. Overrides the "
         "global -paytxfee command line parameter.\n",
         {
             {"amount", RPCArg::Type::AMOUNT, RPCArg::Optional::NO,
              "The transaction fee in " + CURRENCY_UNIT + "/kB"},
         },
         RPCResult{"true|false        (boolean) Returns true if successful\n"},
         RPCExamples{HelpExampleCli("settxfee", "0.00001") +
                     HelpExampleRpc("settxfee", "0.00001")},
     }
         .Check(request);
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     Amount nAmount = AmountFromValue(request.params[0]);
     CFeeRate tx_fee_rate(nAmount, 1000);
     if (tx_fee_rate == CFeeRate()) {
         // automatic selection
     } else if (tx_fee_rate < pwallet->chain().relayMinFee()) {
         throw JSONRPCError(
             RPC_INVALID_PARAMETER,
             strprintf("txfee cannot be less than min relay tx fee (%s)",
                       pwallet->chain().relayMinFee().ToString()));
     } else if (tx_fee_rate < pwallet->m_min_fee) {
         throw JSONRPCError(
             RPC_INVALID_PARAMETER,
             strprintf("txfee cannot be less than wallet min fee (%s)",
                       pwallet->m_min_fee.ToString()));
     }
 
     pwallet->m_pay_tx_fee = tx_fee_rate;
     return true;
 }
 
 static UniValue getbalances(const Config &config,
                             const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const rpc_wallet =
         GetWalletForJSONRPCRequest(request);
     if (!EnsureWalletIsAvailable(rpc_wallet.get(), request.fHelp)) {
         return NullUniValue;
     }
     CWallet &wallet = *rpc_wallet;
 
     RPCHelpMan{
         "getbalances",
         "Returns an object with all balances in " + CURRENCY_UNIT + ".\n",
         {},
         RPCResult{
             "{\n"
             "    \"mine\": {                        (object) balances from "
             "outputs that the wallet can sign\n"
             "      \"trusted\": xxx                 (numeric) trusted balance "
             "(outputs created by the wallet or confirmed outputs)\n"
             "      \"untrusted_pending\": xxx       (numeric) untrusted "
             "pending balance (outputs created by others that are in the "
             "mempool)\n"
             "      \"immature\": xxx                (numeric) balance from "
             "immature coinbase outputs\n"
             "      \"used\": xxx                    (numeric) (only present if "
             "avoid_reuse is set) balance from coins sent to addresses that "
             "were previously spent from (potentially privacy violating)\n"
             "    },\n"
             "    \"watchonly\": {                   (object) watchonly "
             "balances (not present if wallet does not watch anything)\n"
             "      \"trusted\": xxx                 (numeric) trusted balance "
             "(outputs created by the wallet or confirmed outputs)\n"
             "      \"untrusted_pending\": xxx       (numeric) untrusted "
             "pending balance (outputs created by others that are in the "
             "mempool)\n"
             "      \"immature\": xxx                (numeric) balance from "
             "immature coinbase outputs\n"
             "    },\n"
             "}\n"},
         RPCExamples{HelpExampleCli("getbalances", "") +
                     HelpExampleRpc("getbalances", "")},
     }
         .Check(request);
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     wallet.BlockUntilSyncedToCurrentChain();
 
     auto locked_chain = wallet.chain().lock();
     LOCK(wallet.cs_wallet);
 
     UniValue obj(UniValue::VOBJ);
 
     const auto bal = wallet.GetBalance();
     UniValue balances{UniValue::VOBJ};
     {
         UniValue balances_mine{UniValue::VOBJ};
         balances_mine.pushKV("trusted", ValueFromAmount(bal.m_mine_trusted));
         balances_mine.pushKV("untrusted_pending",
                              ValueFromAmount(bal.m_mine_untrusted_pending));
         balances_mine.pushKV("immature", ValueFromAmount(bal.m_mine_immature));
         if (wallet.IsWalletFlagSet(WALLET_FLAG_AVOID_REUSE)) {
             // If the AVOID_REUSE flag is set, bal has been set to just the
             // un-reused address balance. Get the total balance, and then
             // subtract bal to get the reused address balance.
             const auto full_bal = wallet.GetBalance(0, false);
             balances_mine.pushKV(
                 "used", ValueFromAmount(full_bal.m_mine_trusted +
                                         full_bal.m_mine_untrusted_pending -
                                         bal.m_mine_trusted -
                                         bal.m_mine_untrusted_pending));
         }
         balances.pushKV("mine", balances_mine);
     }
     auto spk_man = wallet.GetLegacyScriptPubKeyMan();
     if (spk_man && spk_man->HaveWatchOnly()) {
         UniValue balances_watchonly{UniValue::VOBJ};
         balances_watchonly.pushKV("trusted",
                                   ValueFromAmount(bal.m_watchonly_trusted));
         balances_watchonly.pushKV(
             "untrusted_pending",
             ValueFromAmount(bal.m_watchonly_untrusted_pending));
         balances_watchonly.pushKV("immature",
                                   ValueFromAmount(bal.m_watchonly_immature));
         balances.pushKV("watchonly", balances_watchonly);
     }
     return balances;
 }
 
 static UniValue getwalletinfo(const Config &config,
                               const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "getwalletinfo",
         "Returns an object containing various wallet state info.\n",
         {},
         RPCResult{
             "{\n"
             "  \"walletname\": xxxxx,             (string) the wallet name\n"
             "  \"walletversion\": xxxxx,          (numeric) the wallet "
             "version\n"
             "  \"balance\": xxxxxxx,              (numeric) DEPRECATED. "
             "Identical to getbalances().mine.trusted\n"
             "  \"unconfirmed_balance\": xxx,      (numeric) DEPRECATED. "
             "Identical to getbalances().mine.untrusted_pending\n"
             "  \"immature_balance\": xxxxxx,      (numeric) DEPRECATED. "
             "Identical to getbalances().mine.immature\n"
             "  \"txcount\": xxxxxxx,              (numeric) the total number "
             "of transactions in the wallet\n"
             "  \"keypoololdest\": xxxxxx,           (numeric) the " +
             UNIX_EPOCH_TIME +
             " of the oldest pre-generated key in the key pool\n"
             "  \"keypoolsize\": xxxx,             (numeric) how many new keys "
             "are pre-generated (only counts external keys)\n"
             "  \"keypoolsize_hd_internal\": xxxx, (numeric) how many new keys "
             "are pre-generated for internal use (used for change outputs, only "
             "appears if the wallet is using this feature, otherwise external "
             "keys are used)\n"
             "  \"unlocked_until\": ttt,             (numeric) the " +
             UNIX_EPOCH_TIME +
             " until which the wallet is unlocked for transfers, or 0 if the "
             "wallet is locked\n"
             "  \"paytxfee\": x.xxxx,              (numeric) the transaction "
             "fee configuration, set in " +
             CURRENCY_UNIT +
             "/kB\n"
             "  \"hdseedid\": \"<hash160>\"          (string, optional) the "
             "Hash160 of the HD seed (only present when HD is enabled)\n"
             "  \"private_keys_enabled\": true|false (boolean) false if "
             "privatekeys are disabled for this wallet (enforced watch-only "
             "wallet)\n"
             "  \"scanning\":                        (json object) current "
             "scanning details, or false if no scan is in progress\n"
             "    {\n"
             "      \"duration\" : xxxx              (numeric) elapsed seconds "
             "since scan start\n"
             "      \"progress\" : x.xxxx,           (numeric) scanning "
             "progress percentage [0.0, 1.0]\n"
             "    }\n"
             "  \"avoid_reuse\": true|false          (boolean) whether this "
             "wallet tracks clean/dirty coins in terms of reuse\n"
             "}\n"},
         RPCExamples{HelpExampleCli("getwalletinfo", "") +
                     HelpExampleRpc("getwalletinfo", "")},
     }
         .Check(request);
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
 
     UniValue obj(UniValue::VOBJ);
 
     size_t kpExternalSize = pwallet->KeypoolCountExternalKeys();
     const auto bal = pwallet->GetBalance();
     obj.pushKV("walletname", pwallet->GetName());
     obj.pushKV("walletversion", pwallet->GetVersion());
     obj.pushKV("balance", ValueFromAmount(bal.m_mine_trusted));
     obj.pushKV("unconfirmed_balance",
                ValueFromAmount(bal.m_mine_untrusted_pending));
     obj.pushKV("immature_balance", ValueFromAmount(bal.m_mine_immature));
     obj.pushKV("txcount", (int)pwallet->mapWallet.size());
     obj.pushKV("keypoololdest", pwallet->GetOldestKeyPoolTime());
     obj.pushKV("keypoolsize", (int64_t)kpExternalSize);
 
     LegacyScriptPubKeyMan *spk_man = pwallet->GetLegacyScriptPubKeyMan();
     if (spk_man) {
         CKeyID seed_id = spk_man->GetHDChain().seed_id;
         if (!seed_id.IsNull()) {
             obj.pushKV("hdseedid", seed_id.GetHex());
         }
     }
 
     if (pwallet->CanSupportFeature(FEATURE_HD_SPLIT)) {
         obj.pushKV("keypoolsize_hd_internal",
                    int64_t(pwallet->GetKeyPoolSize() - kpExternalSize));
     }
     if (pwallet->IsCrypted()) {
         obj.pushKV("unlocked_until", pwallet->nRelockTime);
     }
     obj.pushKV("paytxfee", ValueFromAmount(pwallet->m_pay_tx_fee.GetFeePerK()));
     obj.pushKV("private_keys_enabled",
                !pwallet->IsWalletFlagSet(WALLET_FLAG_DISABLE_PRIVATE_KEYS));
     if (pwallet->IsScanning()) {
         UniValue scanning(UniValue::VOBJ);
         scanning.pushKV("duration", pwallet->ScanningDuration() / 1000);
         scanning.pushKV("progress", pwallet->ScanningProgress());
         obj.pushKV("scanning", scanning);
     } else {
         obj.pushKV("scanning", false);
     }
     obj.pushKV("avoid_reuse",
                pwallet->IsWalletFlagSet(WALLET_FLAG_AVOID_REUSE));
     return obj;
 }
 
 static UniValue listwalletdir(const Config &config,
                               const JSONRPCRequest &request) {
     RPCHelpMan{
         "listwalletdir",
         "Returns a list of wallets in the wallet directory.\n",
         {},
         RPCResult{
             "{\n"
             "  \"wallets\" : [                (json array of objects)\n"
             "    {\n"
             "      \"name\" : \"name\"          (string) The wallet name\n"
             "    }\n"
             "    ,...\n"
             "  ]\n"
             "}\n"},
         RPCExamples{HelpExampleCli("listwalletdir", "") +
                     HelpExampleRpc("listwalletdir", "")},
     }
         .Check(request);
 
     UniValue wallets(UniValue::VARR);
     for (const auto &path : ListWalletDir()) {
         UniValue wallet(UniValue::VOBJ);
         wallet.pushKV("name", path.string());
         wallets.push_back(wallet);
     }
 
     UniValue result(UniValue::VOBJ);
     result.pushKV("wallets", wallets);
     return result;
 }
 
 static UniValue listwallets(const Config &config,
                             const JSONRPCRequest &request) {
     RPCHelpMan{
         "listwallets",
         "Returns a list of currently loaded wallets.\n"
         "For full information on the wallet, use \"getwalletinfo\"\n",
         {},
         RPCResult{"[                         (json array of strings)\n"
                   "  \"walletname\"            (string) the wallet name\n"
                   "   ...\n"
                   "]\n"},
         RPCExamples{HelpExampleCli("listwallets", "") +
                     HelpExampleRpc("listwallets", "")},
     }
         .Check(request);
 
     UniValue obj(UniValue::VARR);
 
     for (const std::shared_ptr<CWallet> &wallet : GetWallets()) {
         if (!EnsureWalletIsAvailable(wallet.get(), request.fHelp)) {
             return NullUniValue;
         }
 
         LOCK(wallet->cs_wallet);
 
         obj.push_back(wallet->GetName());
     }
 
     return obj;
 }
 
 static UniValue loadwallet(const Config &config,
                            const JSONRPCRequest &request) {
     RPCHelpMan{
         "loadwallet",
         "Loads a wallet from a wallet file or directory."
         "\nNote that all wallet command-line options used when starting "
         "bitcoind will be"
         "\napplied to the new wallet (eg -zapwallettxes, upgradewallet, "
         "rescan, etc).\n",
         {
             {"filename", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The wallet directory or .dat file."},
         },
         RPCResult{"{\n"
                   "  \"name\" :    <wallet_name>,        (string) The wallet "
                   "name if loaded successfully.\n"
                   "  \"warning\" : <warning>,            (string) Warning "
                   "message if wallet was not loaded cleanly.\n"
                   "}\n"},
         RPCExamples{HelpExampleCli("loadwallet", "\"test.dat\"") +
                     HelpExampleRpc("loadwallet", "\"test.dat\"")},
     }
         .Check(request);
 
     const CChainParams &chainParams = config.GetChainParams();
 
     WalletLocation location(request.params[0].get_str());
 
     if (!location.Exists()) {
         throw JSONRPCError(RPC_WALLET_NOT_FOUND,
                            "Wallet " + location.GetName() + " not found.");
     } else if (fs::is_directory(location.GetPath())) {
         // The given filename is a directory. Check that there's a wallet.dat
         // file.
         fs::path wallet_dat_file = location.GetPath() / "wallet.dat";
         if (fs::symlink_status(wallet_dat_file).type() == fs::file_not_found) {
             throw JSONRPCError(RPC_WALLET_NOT_FOUND,
                                "Directory " + location.GetName() +
                                    " does not contain a wallet.dat file.");
         }
     }
 
     bilingual_str error;
     std::vector<bilingual_str> warnings;
     std::shared_ptr<CWallet> const wallet =
         LoadWallet(chainParams, *g_rpc_chain, location, error, warnings);
     if (!wallet) {
         throw JSONRPCError(RPC_WALLET_ERROR, error.original);
     }
 
     UniValue obj(UniValue::VOBJ);
     obj.pushKV("name", wallet->GetName());
     obj.pushKV("warning", Join(warnings, "\n", OpOriginal));
 
     return obj;
 }
 
 static UniValue setwalletflag(const Config &config,
                               const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     std::string flags = "";
     for (auto &it : WALLET_FLAG_MAP) {
         if (it.second & MUTABLE_WALLET_FLAGS) {
             flags += (flags == "" ? "" : ", ") + it.first;
         }
     }
     RPCHelpMan{
         "setwalletflag",
         "Change the state of the given wallet flag for a wallet.\n",
         {
             {"flag", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The name of the flag to change. Current available flags: " +
                  flags},
             {"value", RPCArg::Type::BOOL, /* default */ "true",
              "The new state."},
         },
         RPCResult{
             "{\n"
             "    \"flag_name\": string   (string) The name of the flag that "
             "was modified\n"
             "    \"flag_state\": bool    (bool) The new state of the flag\n"
             "    \"warnings\": string    (string) Any warnings associated with "
             "the change\n"
             "}\n"},
         RPCExamples{HelpExampleCli("setwalletflag", "avoid_reuse") +
                     HelpExampleRpc("setwalletflag", "\"avoid_reuse\"")},
     }
         .Check(request);
 
     std::string flag_str = request.params[0].get_str();
     bool value = request.params[1].isNull() || request.params[1].get_bool();
 
     if (!WALLET_FLAG_MAP.count(flag_str)) {
         throw JSONRPCError(RPC_INVALID_PARAMETER,
                            strprintf("Unknown wallet flag: %s", flag_str));
     }
 
     auto flag = WALLET_FLAG_MAP.at(flag_str);
 
     if (!(flag & MUTABLE_WALLET_FLAGS)) {
         throw JSONRPCError(RPC_INVALID_PARAMETER,
                            strprintf("Wallet flag is immutable: %s", flag_str));
     }
 
     UniValue res(UniValue::VOBJ);
 
     if (pwallet->IsWalletFlagSet(flag) == value) {
         throw JSONRPCError(RPC_INVALID_PARAMETER,
                            strprintf("Wallet flag is already set to %s: %s",
                                      value ? "true" : "false", flag_str));
     }
 
     res.pushKV("flag_name", flag_str);
     res.pushKV("flag_state", value);
 
     if (value) {
         pwallet->SetWalletFlag(flag);
     } else {
         pwallet->UnsetWalletFlag(flag);
     }
 
     if (flag && value && WALLET_FLAG_CAVEATS.count(flag)) {
         res.pushKV("warnings", WALLET_FLAG_CAVEATS.at(flag));
     }
 
     return res;
 }
 
 static UniValue createwallet(const Config &config,
                              const JSONRPCRequest &request) {
     RPCHelpMan{
         "createwallet",
         "Creates and loads a new wallet.\n",
         {
             {"wallet_name", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The name for the new wallet. If this is a path, the wallet will "
              "be created at the path location."},
             {"disable_private_keys", RPCArg::Type::BOOL, /* default */ "false",
              "Disable the possibility of private keys (only watchonlys are "
              "possible in this mode)."},
             {"blank", RPCArg::Type::BOOL, /* default */ "false",
              "Create a blank wallet. A blank wallet has no keys or HD seed. "
              "One can be set using sethdseed."},
             {"passphrase", RPCArg::Type::STR, RPCArg::Optional::OMITTED,
              "Encrypt the wallet with this passphrase."},
             {"avoid_reuse", RPCArg::Type::BOOL, /* default */ "false",
              "Keep track of coin reuse, and treat dirty and clean coins "
              "differently with privacy considerations in mind."},
         },
         RPCResult{"{\n"
                   "  \"name\" :    <wallet_name>,        (string) The wallet "
                   "name if created successfully. If the wallet was created "
                   "using a full path, the wallet_name will be the full path.\n"
                   "  \"warning\" : <warning>,            (string) Warning "
                   "message if wallet was not loaded cleanly.\n"
                   "}\n"},
         RPCExamples{HelpExampleCli("createwallet", "\"testwallet\"") +
                     HelpExampleRpc("createwallet", "\"testwallet\"")},
     }
         .Check(request);
 
     uint64_t flags = 0;
     if (!request.params[1].isNull() && request.params[1].get_bool()) {
         flags |= WALLET_FLAG_DISABLE_PRIVATE_KEYS;
     }
 
     if (!request.params[2].isNull() && request.params[2].get_bool()) {
         flags |= WALLET_FLAG_BLANK_WALLET;
     }
 
     SecureString passphrase;
     passphrase.reserve(100);
     std::vector<bilingual_str> warnings;
     if (!request.params[3].isNull()) {
         passphrase = request.params[3].get_str().c_str();
         if (passphrase.empty()) {
             // Empty string means unencrypted
             warnings.emplace_back(
                 Untranslated("Empty string given as passphrase, wallet will "
                              "not be encrypted."));
         }
     }
 
     if (!request.params[4].isNull() && request.params[4].get_bool()) {
         flags |= WALLET_FLAG_AVOID_REUSE;
     }
 
     bilingual_str error;
     std::shared_ptr<CWallet> wallet;
     WalletCreationStatus status =
         CreateWallet(config.GetChainParams(), *g_rpc_chain, passphrase, flags,
                      request.params[0].get_str(), error, warnings, wallet);
     switch (status) {
         case WalletCreationStatus::CREATION_FAILED:
             throw JSONRPCError(RPC_WALLET_ERROR, error.original);
         case WalletCreationStatus::ENCRYPTION_FAILED:
             throw JSONRPCError(RPC_WALLET_ENCRYPTION_FAILED, error.original);
         case WalletCreationStatus::SUCCESS:
             break;
             // no default case, so the compiler can warn about missing cases
     }
 
     UniValue obj(UniValue::VOBJ);
     obj.pushKV("name", wallet->GetName());
     obj.pushKV("warning", Join(warnings, "\n", OpOriginal));
 
     return obj;
 }
 
 static UniValue unloadwallet(const Config &config,
                              const JSONRPCRequest &request) {
     RPCHelpMan{
         "unloadwallet",
         "Unloads the wallet referenced by the request endpoint otherwise "
         "unloads the wallet specified in the argument.\n"
         "Specifying the wallet name on a wallet endpoint is invalid.",
         {
             {"wallet_name", RPCArg::Type::STR,
              /* default */ "the wallet name from the RPC request",
              "The name of the wallet to unload."},
         },
         RPCResults{},
         RPCExamples{HelpExampleCli("unloadwallet", "wallet_name") +
                     HelpExampleRpc("unloadwallet", "wallet_name")},
     }
         .Check(request);
 
     std::string wallet_name;
     if (GetWalletNameFromJSONRPCRequest(request, wallet_name)) {
         if (!request.params[0].isNull()) {
             throw JSONRPCError(RPC_INVALID_PARAMETER,
                                "Cannot unload the requested wallet");
         }
     } else {
         wallet_name = request.params[0].get_str();
     }
 
     std::shared_ptr<CWallet> wallet = GetWallet(wallet_name);
     if (!wallet) {
         throw JSONRPCError(RPC_WALLET_NOT_FOUND,
                            "Requested wallet does not exist or is not loaded");
     }
 
     // Release the "main" shared pointer and prevent further notifications.
     // Note that any attempt to load the same wallet would fail until the wallet
     // is destroyed (see CheckUniqueFileid).
     if (!RemoveWallet(wallet)) {
         throw JSONRPCError(RPC_MISC_ERROR, "Requested wallet already unloaded");
     }
 
     UnloadWallet(std::move(wallet));
 
     return NullUniValue;
 }
 
 static UniValue listunspent(const Config &config,
                             const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "listunspent",
         "Returns array of unspent transaction outputs\n"
         "with between minconf and maxconf (inclusive) confirmations.\n"
         "Optionally filter to only include txouts paid to specified "
         "addresses.\n",
         {
             {"minconf", RPCArg::Type::NUM, /* default */ "1",
              "The minimum confirmations to filter"},
             {"maxconf", RPCArg::Type::NUM, /* default */ "9999999",
              "The maximum confirmations to filter"},
             {
                 "addresses",
                 RPCArg::Type::ARR,
                 /* default */ "empty array",
                 "A json array of bitcoin addresses to filter",
                 {
                     {"address", RPCArg::Type::STR, RPCArg::Optional::OMITTED,
                      "bitcoin address"},
                 },
             },
             {"include_unsafe", RPCArg::Type::BOOL, /* default */ "true",
              "Include outputs that are not safe to spend\n"
              "                  See description of \"safe\" attribute below."},
             {"query_options",
              RPCArg::Type::OBJ,
              RPCArg::Optional::OMITTED_NAMED_ARG,
              "JSON with query options",
              {
                  {"minimumAmount", RPCArg::Type::AMOUNT, /* default */ "0",
                   "Minimum value of each UTXO in " + CURRENCY_UNIT + ""},
                  {"maximumAmount", RPCArg::Type::AMOUNT,
                   /* default */ "unlimited",
                   "Maximum value of each UTXO in " + CURRENCY_UNIT + ""},
                  {"maximumCount", RPCArg::Type::NUM, /* default */ "unlimited",
                   "Maximum number of UTXOs"},
                  {"minimumSumAmount", RPCArg::Type::AMOUNT,
                   /* default */ "unlimited",
                   "Minimum sum value of all UTXOs in " + CURRENCY_UNIT + ""},
              },
              "query_options"},
         },
         RPCResult{
             "[                   (array of json object)\n"
             "  {\n"
             "    \"txid\" : \"txid\",        (string) the transaction id\n"
             "    \"vout\" : n,               (numeric) the vout value\n"
             "    \"address\" : \"address\",  (string) the bitcoin address\n"
             "    \"label\" : \"label\",      (string) The associated label, or "
             "\"\" for the default label\n"
             "    \"scriptPubKey\" : \"key\", (string) the script key\n"
             "    \"amount\" : x.xxx,         (numeric) the transaction output "
             "amount in " +
             CURRENCY_UNIT +
             "\n"
             "    \"confirmations\" : n,      (numeric) The number of "
             "confirmations\n"
             "    \"redeemScript\" : n        (string) The redeemScript if "
             "scriptPubKey is P2SH\n"
             "    \"spendable\" : xxx,        (bool) Whether we have the "
             "private keys to spend this output\n"
             "    \"solvable\" : xxx,         (bool) Whether we know how to "
             "spend this output, ignoring the lack of keys\n"
             "    \"reused\" : xxx,           (bool) (only present if "
             "avoid_reuse is set) Whether this output is reused/dirty (sent to "
             "an address that was previously spent from)\n"
             "    \"desc\" : xxx,             (string, only when solvable) A "
             "descriptor for spending this output\n"
             "    \"safe\" : xxx              (bool) Whether this output is "
             "considered safe to spend. Unconfirmed transactions\n"
             "                              from outside keys are considered "
             "unsafe and are not eligible for spending by\n"
             "                              fundrawtransaction and "
             "sendtoaddress.\n"
             "  }\n"
             "  ,...\n"
             "]\n"},
         RPCExamples{
             HelpExampleCli("listunspent", "") +
             HelpExampleCli("listunspent",
                            "6 9999999 "
                            "\"[\\\"1PGFqEzfmQch1gKD3ra4k18PNj3tTUUSqg\\\","
                            "\\\"1LtvqCaApEdUGFkpKMM4MstjcaL4dKg8SP\\\"]\"") +
             HelpExampleRpc("listunspent",
                            "6, 9999999 "
                            "\"[\\\"1PGFqEzfmQch1gKD3ra4k18PNj3tTUUSqg\\\","
                            "\\\"1LtvqCaApEdUGFkpKMM4MstjcaL4dKg8SP\\\"]\"") +
             HelpExampleCli(
                 "listunspent",
                 "6 9999999 '[]' true '{ \"minimumAmount\": 0.005 }'") +
             HelpExampleRpc(
                 "listunspent",
                 "6, 9999999, [] , true, { \"minimumAmount\": 0.005 } ")},
     }
         .Check(request);
 
     int nMinDepth = 1;
     if (!request.params[0].isNull()) {
         RPCTypeCheckArgument(request.params[0], UniValue::VNUM);
         nMinDepth = request.params[0].get_int();
     }
 
     int nMaxDepth = 9999999;
     if (!request.params[1].isNull()) {
         RPCTypeCheckArgument(request.params[1], UniValue::VNUM);
         nMaxDepth = request.params[1].get_int();
     }
 
     std::set<CTxDestination> destinations;
     if (!request.params[2].isNull()) {
         RPCTypeCheckArgument(request.params[2], UniValue::VARR);
         UniValue inputs = request.params[2].get_array();
         for (size_t idx = 0; idx < inputs.size(); idx++) {
             const UniValue &input = inputs[idx];
             CTxDestination dest =
                 DecodeDestination(input.get_str(), wallet->chainParams);
             if (!IsValidDestination(dest)) {
                 throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY,
                                    std::string("Invalid Bitcoin address: ") +
                                        input.get_str());
             }
             if (!destinations.insert(dest).second) {
                 throw JSONRPCError(
                     RPC_INVALID_PARAMETER,
                     std::string("Invalid parameter, duplicated address: ") +
                         input.get_str());
             }
         }
     }
 
     bool include_unsafe = true;
     if (!request.params[3].isNull()) {
         RPCTypeCheckArgument(request.params[3], UniValue::VBOOL);
         include_unsafe = request.params[3].get_bool();
     }
 
     Amount nMinimumAmount = Amount::zero();
     Amount nMaximumAmount = MAX_MONEY;
     Amount nMinimumSumAmount = MAX_MONEY;
     uint64_t nMaximumCount = 0;
 
     if (!request.params[4].isNull()) {
         const UniValue &options = request.params[4].get_obj();
 
         if (options.exists("minimumAmount")) {
             nMinimumAmount = AmountFromValue(options["minimumAmount"]);
         }
 
         if (options.exists("maximumAmount")) {
             nMaximumAmount = AmountFromValue(options["maximumAmount"]);
         }
 
         if (options.exists("minimumSumAmount")) {
             nMinimumSumAmount = AmountFromValue(options["minimumSumAmount"]);
         }
 
         if (options.exists("maximumCount")) {
             nMaximumCount = options["maximumCount"].get_int64();
         }
     }
 
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
     UniValue results(UniValue::VARR);
     std::vector<COutput> vecOutputs;
     {
         CCoinControl cctl;
         cctl.m_avoid_address_reuse = false;
         cctl.m_min_depth = nMinDepth;
         cctl.m_max_depth = nMaxDepth;
         auto locked_chain = pwallet->chain().lock();
         LOCK(pwallet->cs_wallet);
         pwallet->AvailableCoins(*locked_chain, vecOutputs, !include_unsafe,
                                 &cctl, nMinimumAmount, nMaximumAmount,
                                 nMinimumSumAmount, nMaximumCount);
     }
 
     LOCK(pwallet->cs_wallet);
 
     const bool avoid_reuse = pwallet->IsWalletFlagSet(WALLET_FLAG_AVOID_REUSE);
 
     for (const COutput &out : vecOutputs) {
         CTxDestination address;
         const CScript &scriptPubKey = out.tx->tx->vout[out.i].scriptPubKey;
         bool fValidAddress = ExtractDestination(scriptPubKey, address);
         bool reused =
             avoid_reuse && pwallet->IsUsedDestination(out.tx->GetId(), out.i);
 
         if (destinations.size() &&
             (!fValidAddress || !destinations.count(address))) {
             continue;
         }
 
         UniValue entry(UniValue::VOBJ);
         entry.pushKV("txid", out.tx->GetId().GetHex());
         entry.pushKV("vout", out.i);
 
         if (fValidAddress) {
             entry.pushKV("address", EncodeDestination(address, config));
 
             const auto *address_book_entry =
                 pwallet->FindAddressBookEntry(address);
             if (address_book_entry) {
                 entry.pushKV("label", address_book_entry->GetLabel());
             }
 
             std::unique_ptr<SigningProvider> provider =
                 pwallet->GetSigningProvider(scriptPubKey);
             if (provider) {
                 if (scriptPubKey.IsPayToScriptHash()) {
                     const CScriptID &hash =
                         CScriptID(boost::get<ScriptHash>(address));
                     CScript redeemScript;
                     if (provider->GetCScript(hash, redeemScript)) {
                         entry.pushKV(
                             "redeemScript",
                             HexStr(redeemScript.begin(), redeemScript.end()));
                     }
                 }
             }
         }
 
         entry.pushKV("scriptPubKey",
                      HexStr(scriptPubKey.begin(), scriptPubKey.end()));
         entry.pushKV("amount", ValueFromAmount(out.tx->tx->vout[out.i].nValue));
         entry.pushKV("confirmations", out.nDepth);
         entry.pushKV("spendable", out.fSpendable);
         entry.pushKV("solvable", out.fSolvable);
         if (out.fSolvable) {
             std::unique_ptr<SigningProvider> provider =
                 pwallet->GetSigningProvider(scriptPubKey);
             if (provider) {
                 auto descriptor = InferDescriptor(scriptPubKey, *provider);
                 entry.pushKV("desc", descriptor->ToString());
             }
         }
         if (avoid_reuse) {
             entry.pushKV("reused", reused);
         }
         entry.pushKV("safe", out.fSafe);
         results.push_back(entry);
     }
 
     return results;
 }
 
 void FundTransaction(CWallet *const pwallet, CMutableTransaction &tx,
                      Amount &fee_out, int &change_position, UniValue options) {
     // Make sure the results are valid at least up to the most recent block
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
     CCoinControl coinControl;
     change_position = -1;
     bool lockUnspents = false;
     UniValue subtractFeeFromOutputs;
     std::set<int> setSubtractFeeFromOutputs;
 
     if (!options.isNull()) {
         if (options.type() == UniValue::VBOOL) {
             // backward compatibility bool only fallback
             coinControl.fAllowWatchOnly = options.get_bool();
         } else {
             RPCTypeCheckArgument(options, UniValue::VOBJ);
             RPCTypeCheckObj(
                 options,
                 {
                     {"changeAddress", UniValueType(UniValue::VSTR)},
                     {"changePosition", UniValueType(UniValue::VNUM)},
                     {"includeWatching", UniValueType(UniValue::VBOOL)},
                     {"lockUnspents", UniValueType(UniValue::VBOOL)},
                     // will be checked below
                     {"feeRate", UniValueType()},
                     {"subtractFeeFromOutputs", UniValueType(UniValue::VARR)},
                 },
                 true, true);
 
             if (options.exists("changeAddress")) {
                 CTxDestination dest = DecodeDestination(
                     options["changeAddress"].get_str(), pwallet->chainParams);
 
                 if (!IsValidDestination(dest)) {
                     throw JSONRPCError(
                         RPC_INVALID_ADDRESS_OR_KEY,
                         "changeAddress must be a valid bitcoin address");
                 }
 
                 coinControl.destChange = dest;
             }
 
             if (options.exists("changePosition")) {
                 change_position = options["changePosition"].get_int();
             }
 
             coinControl.fAllowWatchOnly =
                 ParseIncludeWatchonly(options["includeWatching"], *pwallet);
 
             if (options.exists("lockUnspents")) {
                 lockUnspents = options["lockUnspents"].get_bool();
             }
 
             if (options.exists("feeRate")) {
                 coinControl.m_feerate =
                     CFeeRate(AmountFromValue(options["feeRate"]));
                 coinControl.fOverrideFeeRate = true;
             }
 
             if (options.exists("subtractFeeFromOutputs")) {
                 subtractFeeFromOutputs =
                     options["subtractFeeFromOutputs"].get_array();
             }
         }
     } else {
         // if options is null and not a bool
         coinControl.fAllowWatchOnly =
             ParseIncludeWatchonly(NullUniValue, *pwallet);
     }
 
     if (tx.vout.size() == 0) {
         throw JSONRPCError(RPC_INVALID_PARAMETER,
                            "TX must have at least one output");
     }
 
     if (change_position != -1 &&
         (change_position < 0 ||
          (unsigned int)change_position > tx.vout.size())) {
         throw JSONRPCError(RPC_INVALID_PARAMETER,
                            "changePosition out of bounds");
     }
 
     for (size_t idx = 0; idx < subtractFeeFromOutputs.size(); idx++) {
         int pos = subtractFeeFromOutputs[idx].get_int();
         if (setSubtractFeeFromOutputs.count(pos)) {
             throw JSONRPCError(
                 RPC_INVALID_PARAMETER,
                 strprintf("Invalid parameter, duplicated position: %d", pos));
         }
         if (pos < 0) {
             throw JSONRPCError(
                 RPC_INVALID_PARAMETER,
                 strprintf("Invalid parameter, negative position: %d", pos));
         }
         if (pos >= int(tx.vout.size())) {
             throw JSONRPCError(
                 RPC_INVALID_PARAMETER,
                 strprintf("Invalid parameter, position too large: %d", pos));
         }
         setSubtractFeeFromOutputs.insert(pos);
     }
 
     bilingual_str error;
 
     if (!pwallet->FundTransaction(tx, fee_out, change_position, error,
                                   lockUnspents, setSubtractFeeFromOutputs,
                                   coinControl)) {
         throw JSONRPCError(RPC_WALLET_ERROR, error.original);
     }
 }
 
 static UniValue fundrawtransaction(const Config &config,
                                    const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "fundrawtransaction",
         "Add inputs to a transaction until it has enough in value to meet "
         "its out value.\n"
         "This will not modify existing inputs, and will add at most one change "
         "output to the outputs.\n"
         "No existing outputs will be modified unless "
         "\"subtractFeeFromOutputs\" is specified.\n"
         "Note that inputs which were signed may need to be resigned after "
         "completion since in/outputs have been added.\n"
         "The inputs added will not be signed, use signrawtransactionwithkey or "
         "signrawtransactionwithwallet for that.\n"
         "Note that all existing inputs must have their previous output "
         "transaction be in the wallet.\n"
         "Note that all inputs selected must be of standard form and P2SH "
         "scripts must be\n"
         "in the wallet using importaddress or addmultisigaddress (to calculate "
         "fees).\n"
         "You can see whether this is the case by checking the \"solvable\" "
         "field in the listunspent output.\n"
         "Only pay-to-pubkey, multisig, and P2SH versions thereof are currently "
         "supported for watch-only\n",
         {
             {"hexstring", RPCArg::Type::STR_HEX, RPCArg::Optional::NO,
              "The hex string of the raw transaction"},
             {"options",
              RPCArg::Type::OBJ,
              RPCArg::Optional::OMITTED_NAMED_ARG,
              "for backward compatibility: passing in a true instead of an "
              "object will result in {\"includeWatching\":true}",
              {
                  {"changeAddress", RPCArg::Type::STR,
                   /* default */ "pool address",
                   "The bitcoin address to receive the change"},
                  {"changePosition", RPCArg::Type::NUM, /* default */ "",
                   "The index of the change output"},
                  {"includeWatching", RPCArg::Type::BOOL,
                   /* default */ "true for watch-only wallets, otherwise false",
                   "Also select inputs which are watch only.\n"
                   "Only solvable inputs can be used. Watch-only destinations "
                   "are solvable if the public key and/or output script was "
                   "imported,\n"
                   "e.g. with 'importpubkey' or 'importmulti' with the "
                   "'pubkeys' or 'desc' field."},
                  {"lockUnspents", RPCArg::Type::BOOL, /* default */ "false",
                   "Lock selected unspent outputs"},
                  {"feeRate", RPCArg::Type::AMOUNT, /* default */
                   "not set: makes wallet determine the fee",
                   "Set a specific fee rate in " + CURRENCY_UNIT + "/kB"},
                  {
                      "subtractFeeFromOutputs",
                      RPCArg::Type::ARR,
                      /* default */ "empty array",
                      "A json array of integers.\n"
                      "                              The fee will be equally "
                      "deducted from the amount of each specified output.\n"
                      "                              Those recipients will "
                      "receive less bitcoins than you enter in their "
                      "corresponding amount field.\n"
                      "                              If no outputs are "
                      "specified here, the sender pays the fee.",
                      {
                          {"vout_index", RPCArg::Type::NUM,
                           RPCArg::Optional::OMITTED,
                           "The zero-based output index, before a change output "
                           "is added."},
                      },
                  },
              },
              "options"},
         },
         RPCResult{"{\n"
                   "  \"hex\":       \"value\", (string)  The resulting raw "
                   "transaction (hex-encoded string)\n"
                   "  \"fee\":       n,         (numeric) Fee in " +
                   CURRENCY_UNIT +
                   " the resulting transaction pays\n"
                   "  \"changepos\": n          (numeric) The position of the "
                   "added change output, or -1\n"
                   "}\n"},
         RPCExamples{
             "\nCreate a transaction with no inputs\n" +
             HelpExampleCli("createrawtransaction",
                            "\"[]\" \"{\\\"myaddress\\\":0.01}\"") +
             "\nAdd sufficient unsigned inputs to meet the output value\n" +
             HelpExampleCli("fundrawtransaction", "\"rawtransactionhex\"") +
             "\nSign the transaction\n" +
             HelpExampleCli("signrawtransactionwithwallet",
                            "\"fundedtransactionhex\"") +
             "\nSend the transaction\n" +
             HelpExampleCli("sendrawtransaction", "\"signedtransactionhex\"")},
     }
         .Check(request);
 
     RPCTypeCheck(request.params, {UniValue::VSTR, UniValueType()});
 
     // parse hex string from parameter
     CMutableTransaction tx;
     if (!DecodeHexTx(tx, request.params[0].get_str())) {
         throw JSONRPCError(RPC_DESERIALIZATION_ERROR, "TX decode failed");
     }
 
     Amount fee;
     int change_position;
     FundTransaction(pwallet, tx, fee, change_position, request.params[1]);
 
     UniValue result(UniValue::VOBJ);
     result.pushKV("hex", EncodeHexTx(CTransaction(tx)));
     result.pushKV("fee", ValueFromAmount(fee));
     result.pushKV("changepos", change_position);
 
     return result;
 }
 
 UniValue signrawtransactionwithwallet(const Config &config,
                                       const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "signrawtransactionwithwallet",
         "Sign inputs for raw transaction (serialized, hex-encoded).\n"
         "The second optional argument (may be null) is an array of previous "
         "transaction outputs that\n"
         "this transaction depends on but may not yet be in the block chain.\n" +
             HelpRequiringPassphrase(pwallet) + "\n",
         {
             {"hexstring", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The transaction hex string"},
             {
                 "prevtxs",
                 RPCArg::Type::ARR,
                 RPCArg::Optional::OMITTED_NAMED_ARG,
                 "A json array of previous dependent transaction outputs",
                 {
                     {
                         "",
                         RPCArg::Type::OBJ,
                         RPCArg::Optional::OMITTED,
                         "",
                         {
                             {"txid", RPCArg::Type::STR_HEX,
                              RPCArg::Optional::NO, "The transaction id"},
                             {"vout", RPCArg::Type::NUM, RPCArg::Optional::NO,
                              "The output number"},
                             {"scriptPubKey", RPCArg::Type::STR_HEX,
                              RPCArg::Optional::NO, "script key"},
                             {"redeemScript", RPCArg::Type::STR_HEX,
                              RPCArg::Optional::OMITTED, "(required for P2SH)"},
                             {"amount", RPCArg::Type::AMOUNT,
                              RPCArg::Optional::NO, "The amount spent"},
                         },
                     },
                 },
             },
             {"sighashtype", RPCArg::Type::STR, /* default */ "ALL|FORKID",
              "The signature hash type. Must be one of\n"
              "       \"ALL|FORKID\"\n"
              "       \"NONE|FORKID\"\n"
              "       \"SINGLE|FORKID\"\n"
              "       \"ALL|FORKID|ANYONECANPAY\"\n"
              "       \"NONE|FORKID|ANYONECANPAY\"\n"
              "       \"SINGLE|FORKID|ANYONECANPAY\""},
         },
         RPCResult{"{\n"
                   "  \"hex\" : \"value\",          (string) The hex-encoded "
                   "raw transaction with signature(s)\n"
                   "  \"complete\" : true|false,    (boolean) If the "
                   "transaction has a complete set of signatures\n"
                   "  \"errors\" : [                (json array of objects) "
                   "Script verification errors (if there are any)\n"
                   "    {\n"
                   "      \"txid\" : \"hash\",        (string) The hash of the "
                   "referenced, previous transaction\n"
                   "      \"vout\" : n,               (numeric) The index of "
                   "the output to spent and used as input\n"
                   "      \"scriptSig\" : \"hex\",    (string) The hex-encoded "
                   "signature script\n"
                   "      \"sequence\" : n,           (numeric) Script sequence "
                   "number\n"
                   "      \"error\" : \"text\"        (string) Verification or "
                   "signing error related to the input\n"
                   "    }\n"
                   "    ,...\n"
                   "  ]\n"
                   "}\n"},
         RPCExamples{
             HelpExampleCli("signrawtransactionwithwallet", "\"myhex\"") +
             HelpExampleRpc("signrawtransactionwithwallet", "\"myhex\"")},
     }
         .Check(request);
 
     RPCTypeCheck(request.params,
                  {UniValue::VSTR, UniValue::VARR, UniValue::VSTR}, true);
 
     CMutableTransaction mtx;
     if (!DecodeHexTx(mtx, request.params[0].get_str())) {
         throw JSONRPCError(RPC_DESERIALIZATION_ERROR, "TX decode failed");
     }
 
     // Sign the transaction
     auto locked_chain = pwallet->chain().lock();
     LOCK(pwallet->cs_wallet);
     EnsureWalletIsUnlocked(pwallet);
 
     // Fetch previous transactions (inputs):
     std::map<COutPoint, Coin> coins;
     for (const CTxIn &txin : mtx.vin) {
         // Create empty map entry keyed by prevout.
         coins[txin.prevout];
     }
     pwallet->chain().findCoins(coins);
 
     // Parse the prevtxs array
     ParsePrevouts(request.params[1], nullptr, coins);
 
     std::set<std::shared_ptr<SigningProvider>> providers;
     for (const std::pair<COutPoint, Coin> coin_pair : coins) {
         std::unique_ptr<SigningProvider> provider = pwallet->GetSigningProvider(
             coin_pair.second.GetTxOut().scriptPubKey);
         if (provider) {
             providers.insert(std::move(provider));
         }
     }
     if (providers.size() == 0) {
         // When there are no available providers, use a dummy SigningProvider so
         // we can check if the tx is complete
         providers.insert(std::make_shared<SigningProvider>());
     }
 
     UniValue result(UniValue::VOBJ);
     for (std::shared_ptr<SigningProvider> provider : providers) {
         SignTransaction(mtx, provider.get(), coins, request.params[2], result);
     }
     return result;
 }
 
 UniValue rescanblockchain(const Config &config, const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "rescanblockchain",
         "Rescan the local blockchain for wallet related transactions.\n"
         "Note: Use \"getwalletinfo\" to query the scanning progress.\n",
         {
             {"start_height", RPCArg::Type::NUM, /* default */ "0",
              "block height where the rescan should start"},
             {"stop_height", RPCArg::Type::NUM,
              RPCArg::Optional::OMITTED_NAMED_ARG,
              "the last block height that should be scanned"},
         },
         RPCResult{"{\n"
                   "  \"start_height\"     (numeric) The block height where the "
                   "rescan started (the requested height or 0\n"
                   "  \"stop_height\"      (numeric) The height of the last "
                   "rescanned block. May be null in rare cases if there was a "
                   "reorg and the call didn't scan any blocks because they were "
                   "already scanned in the background.\n"
                   "}\n"},
         RPCExamples{HelpExampleCli("rescanblockchain", "100000 120000") +
                     HelpExampleRpc("rescanblockchain", "100000, 120000")},
     }
         .Check(request);
 
     WalletRescanReserver reserver(*pwallet);
     if (!reserver.reserve()) {
         throw JSONRPCError(
             RPC_WALLET_ERROR,
             "Wallet is currently rescanning. Abort existing rescan or wait.");
     }
 
     int start_height = 0;
     BlockHash start_block, stop_block;
     {
         auto locked_chain = pwallet->chain().lock();
         Optional<int> tip_height = locked_chain->getHeight();
 
         if (!request.params[0].isNull()) {
             start_height = request.params[0].get_int();
             if (start_height < 0 || !tip_height || start_height > *tip_height) {
                 throw JSONRPCError(RPC_INVALID_PARAMETER,
                                    "Invalid start_height");
             }
         }
 
         Optional<int> stop_height;
         if (!request.params[1].isNull()) {
             stop_height = request.params[1].get_int();
             if (*stop_height < 0 || !tip_height || *stop_height > *tip_height) {
                 throw JSONRPCError(RPC_INVALID_PARAMETER,
                                    "Invalid stop_height");
             } else if (*stop_height < start_height) {
                 throw JSONRPCError(
                     RPC_INVALID_PARAMETER,
                     "stop_height must be greater than start_height");
             }
         }
 
         // We can't rescan beyond non-pruned blocks, stop and throw an error
         if (locked_chain->findPruned(start_height, stop_height)) {
             throw JSONRPCError(
                 RPC_MISC_ERROR,
                 "Can't rescan beyond pruned data. Use RPC call "
                 "getblockchaininfo to determine your pruned height.");
         }
 
         if (tip_height) {
             start_block = locked_chain->getBlockHash(start_height);
 
             // If called with a stop_height, set the stop_height here to
             // trigger a rescan to that height.
             // If called without a stop height, leave stop_height as null here
             // so rescan continues to the tip (even if the tip advances during
             // rescan).
             if (stop_height) {
                 stop_block = locked_chain->getBlockHash(*stop_height);
             }
         }
     }
 
     CWallet::ScanResult result = pwallet->ScanForWalletTransactions(
         start_block, stop_block, reserver, true /* fUpdate */);
     switch (result.status) {
         case CWallet::ScanResult::SUCCESS:
             break;
         case CWallet::ScanResult::FAILURE:
             throw JSONRPCError(
                 RPC_MISC_ERROR,
                 "Rescan failed. Potentially corrupted data files.");
         case CWallet::ScanResult::USER_ABORT:
             throw JSONRPCError(RPC_MISC_ERROR, "Rescan aborted.");
             // no default case, so the compiler can warn about missing cases
     }
     UniValue response(UniValue::VOBJ);
     response.pushKV("start_height", start_height);
     response.pushKV("stop_height", result.last_scanned_height
                                        ? *result.last_scanned_height
                                        : UniValue());
     return response;
 }
 
 class DescribeWalletAddressVisitor : public boost::static_visitor<UniValue> {
 public:
     const SigningProvider *const provider;
 
     void ProcessSubScript(const CScript &subscript, UniValue &obj) const {
         // Always present: script type and redeemscript
         std::vector<std::vector<uint8_t>> solutions_data;
         txnouttype which_type = Solver(subscript, solutions_data);
         obj.pushKV("script", GetTxnOutputType(which_type));
         obj.pushKV("hex", HexStr(subscript.begin(), subscript.end()));
 
         CTxDestination embedded;
         if (ExtractDestination(subscript, embedded)) {
             // Only when the script corresponds to an address.
             UniValue subobj(UniValue::VOBJ);
             UniValue detail = DescribeAddress(embedded);
             subobj.pushKVs(detail);
             UniValue wallet_detail = boost::apply_visitor(*this, embedded);
             subobj.pushKVs(wallet_detail);
             subobj.pushKV("address", EncodeDestination(embedded, GetConfig()));
             subobj.pushKV("scriptPubKey",
                           HexStr(subscript.begin(), subscript.end()));
             // Always report the pubkey at the top level, so that
             // `getnewaddress()['pubkey']` always works.
             if (subobj.exists("pubkey")) {
                 obj.pushKV("pubkey", subobj["pubkey"]);
             }
             obj.pushKV("embedded", std::move(subobj));
         } else if (which_type == TX_MULTISIG) {
             // Also report some information on multisig scripts (which do not
             // have a corresponding address).
             // TODO: abstract out the common functionality between this logic
             // and ExtractDestinations.
             obj.pushKV("sigsrequired", solutions_data[0][0]);
             UniValue pubkeys(UniValue::VARR);
             for (size_t i = 1; i < solutions_data.size() - 1; ++i) {
                 CPubKey key(solutions_data[i].begin(), solutions_data[i].end());
                 pubkeys.push_back(HexStr(key.begin(), key.end()));
             }
             obj.pushKV("pubkeys", std::move(pubkeys));
         }
     }
 
     explicit DescribeWalletAddressVisitor(const SigningProvider *_provider)
         : provider(_provider) {}
 
     UniValue operator()(const CNoDestination &dest) const {
         return UniValue(UniValue::VOBJ);
     }
 
     UniValue operator()(const PKHash &pkhash) const {
         CKeyID keyID(pkhash);
         UniValue obj(UniValue::VOBJ);
         CPubKey vchPubKey;
         if (provider && provider->GetPubKey(keyID, vchPubKey)) {
             obj.pushKV("pubkey", HexStr(vchPubKey));
             obj.pushKV("iscompressed", vchPubKey.IsCompressed());
         }
         return obj;
     }
 
     UniValue operator()(const ScriptHash &scripthash) const {
         CScriptID scriptID(scripthash);
         UniValue obj(UniValue::VOBJ);
         CScript subscript;
         if (provider && provider->GetCScript(scriptID, subscript)) {
             ProcessSubScript(subscript, obj);
         }
         return obj;
     }
 };
 
 static UniValue DescribeWalletAddress(CWallet *pwallet,
                                       const CTxDestination &dest) {
     UniValue ret(UniValue::VOBJ);
     UniValue detail = DescribeAddress(dest);
     CScript script = GetScriptForDestination(dest);
     std::unique_ptr<SigningProvider> provider = nullptr;
     if (pwallet) {
         provider = pwallet->GetSigningProvider(script);
     }
     ret.pushKVs(detail);
     ret.pushKVs(boost::apply_visitor(
         DescribeWalletAddressVisitor(provider.get()), dest));
     return ret;
 }
 
 /** Convert CAddressBookData to JSON record.  */
 static UniValue AddressBookDataToJSON(const CAddressBookData &data,
                                       const bool verbose) {
     UniValue ret(UniValue::VOBJ);
     if (verbose) {
         ret.pushKV("name", data.GetLabel());
     }
     ret.pushKV("purpose", data.purpose);
     return ret;
 }
 
 UniValue getaddressinfo(const Config &config, const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     const std::string example_address =
         "\"qrmzys48glkpevp2l4t24jtcltc9hyzx9cep2qffm4\"";
 
     RPCHelpMan{
         "getaddressinfo",
         "\nReturn information about the given bitcoin address.\n"
         "Some of the information will only be present if the address is in the "
         "active wallet.\n",
         {
             {"address", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The bitcoin address for which to get information."},
         },
         RPCResult{
             "{\n"
             "  \"address\" : \"address\",              (string) The bitcoin "
             "address validated.\n"
             "  \"scriptPubKey\" : \"hex\",             (string) The "
             "hex-encoded scriptPubKey generated by the address.\n"
             "  \"ismine\" : true|false,              (boolean) If the address "
             "is yours.\n"
             "  \"iswatchonly\" : true|false,         (boolean) If the address "
             "is watchonly.\n"
             "  \"solvable\" : true|false,            (boolean) If we know how "
             "to spend coins sent to this address, ignoring the possible lack "
             "of private keys.\n"
             "  \"desc\" : \"desc\",                    (string, optional) A "
             "descriptor for spending coins sent to this address (only when "
             "solvable).\n"
             "  \"isscript\" : true|false,            (boolean) If the key is a "
             "script.\n"
             "  \"ischange\" : true|false,            (boolean) If the address "
             "was used for change output.\n"
             "  \"script\" : \"type\"                   (string, optional) The "
             "output script type. Only if isscript is true and the redeemscript "
             "is known. Possible\n"
             "                                                         types: "
             "nonstandard, pubkey, pubkeyhash, scripthash, multisig, nulldata\n"
             "  \"hex\" : \"hex\",                      (string, optional) The "
             "redeemscript for the p2sh address.\n"
             "  \"pubkeys\"                           (array, optional) Array "
             "of pubkeys associated with the known redeemscript (only if script "
             "is multisig).\n"
             "    [\n"
             "      \"pubkey\" (string)\n"
             "      ,...\n"
             "    ]\n"
             "  \"sigsrequired\" : xxxxx              (numeric, optional) The "
             "number of signatures required to spend multisig output (only if "
             "script is multisig).\n"
             "  \"pubkey\" : \"publickeyhex\",          (string, optional) The "
             "hex value of the raw public key for single-key addresses "
             "(possibly embedded in P2SH).\n"
             "  \"embedded\" : {...},                 (object, optional) "
             "Information about the address embedded in P2SH, if "
             "relevant and known. Includes all\n"
             "                                                         "
             "getaddressinfo output fields for the embedded address, excluding "
             "metadata (timestamp, hdkeypath,\n"
             "                                                         "
             "hdseedid) and relation to the wallet (ismine, iswatchonly).\n"
             "  \"iscompressed\" : true|false,        (boolean, optional) If "
             "the pubkey is compressed.\n"
             "  \"label\" :  \"label\"                  (string) The label "
             "associated with the address. Defaults to \"\". Equivalent to the "
             "label name in the labels array below.\n"
             "  \"timestamp\" : timestamp,            (number, optional) The "
             "creation time of the key, if available, expressed in " +
             UNIX_EPOCH_TIME +
             ".\n"
             "  \"hdkeypath\" : \"keypath\"             (string, optional) The "
             "HD keypath, if the key is HD and available.\n"
             "  \"hdseedid\" : \"<hash160>\"            (string, optional) The "
             "Hash160 of the HD seed.\n"
             "  \"hdmasterfingerprint\" : \"<hash160>\" (string, optional) The "
             "fingerprint of the master key.\n"
             "  \"labels\"                            (json object) An array of "
             "labels associated with the address. Currently limited to one "
             "label but returned\n"
             "                                               as an array to "
             "keep the API stable if multiple labels are enabled in the "
             "future.\n"
             "    [\n"
             "      \"label name\" (string) The label name. Defaults to \"\". "
             "Equivalent to the label field above.\n\n"
             "      DEPRECATED, will be removed in a future version. To "
             "re-enable, launch bitcoind with `-deprecatedrpc=labelspurpose`:\n"
             "      { (json object of label data)\n"
             "        \"name\" : \"label name\" (string) The label name. "
             "Defaults to \"\". Equivalent to the label field above.\n"
             "        \"purpose\" : \"purpose\" (string) The purpose of the "
             "associated address (send or receive).\n"
             "      },...\n"
             "    ]\n"
             "}\n"},
         RPCExamples{HelpExampleCli("getaddressinfo", example_address) +
                     HelpExampleRpc("getaddressinfo", example_address)},
     }
         .Check(request);
 
     LOCK(pwallet->cs_wallet);
 
     UniValue ret(UniValue::VOBJ);
     CTxDestination dest =
         DecodeDestination(request.params[0].get_str(), wallet->chainParams);
     // Make sure the destination is valid
     if (!IsValidDestination(dest)) {
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Invalid address");
     }
 
     std::string currentAddress = EncodeDestination(dest, config);
     ret.pushKV("address", currentAddress);
 
     CScript scriptPubKey = GetScriptForDestination(dest);
     ret.pushKV("scriptPubKey",
                HexStr(scriptPubKey.begin(), scriptPubKey.end()));
 
     std::unique_ptr<SigningProvider> provider =
         pwallet->GetSigningProvider(scriptPubKey);
 
     isminetype mine = pwallet->IsMine(dest);
     ret.pushKV("ismine", bool(mine & ISMINE_SPENDABLE));
 
     bool solvable = provider && IsSolvable(*provider, scriptPubKey);
     ret.pushKV("solvable", solvable);
 
     if (solvable) {
         ret.pushKV("desc",
                    InferDescriptor(scriptPubKey, *provider)->ToString());
     }
 
     ret.pushKV("iswatchonly", bool(mine & ISMINE_WATCH_ONLY));
 
     UniValue detail = DescribeWalletAddress(pwallet, dest);
     ret.pushKVs(detail);
 
     // Return label field if existing. Currently only one label can be
     // associated with an address, so the label should be equivalent to the
     // value of the name key/value pair in the labels array below.
     const auto *address_book_entry = pwallet->FindAddressBookEntry(dest);
     if (address_book_entry) {
         ret.pushKV("label", address_book_entry->GetLabel());
     }
 
     ret.pushKV("ischange", pwallet->IsChange(scriptPubKey));
 
     ScriptPubKeyMan *spk_man = pwallet->GetScriptPubKeyMan(scriptPubKey);
     if (spk_man) {
         if (const CKeyMetadata *meta = spk_man->GetMetadata(dest)) {
             ret.pushKV("timestamp", meta->nCreateTime);
             if (meta->has_key_origin) {
                 ret.pushKV("hdkeypath", WriteHDKeypath(meta->key_origin.path));
                 ret.pushKV("hdseedid", meta->hd_seed_id.GetHex());
                 ret.pushKV("hdmasterfingerprint",
                            HexStr(meta->key_origin.fingerprint,
                                   meta->key_origin.fingerprint + 4));
             }
         }
     }
 
     // Return a `labels` array containing the label associated with the address,
     // equivalent to the `label` field above. Currently only one label can be
     // associated with an address, but we return an array so the API remains
     // stable if we allow multiple labels to be associated with an address in
     // the future.
     //
     // DEPRECATED: The previous behavior of returning an array containing a JSON
     // object of `name` and `purpose` key/value pairs has been deprecated.
     UniValue labels(UniValue::VARR);
     if (address_book_entry) {
         if (pwallet->chain().rpcEnableDeprecated("labelspurpose")) {
             labels.push_back(AddressBookDataToJSON(*address_book_entry, true));
         } else {
             labels.push_back(address_book_entry->GetLabel());
         }
     }
     ret.pushKV("labels", std::move(labels));
 
     return ret;
 }
 
 UniValue getaddressesbylabel(const Config &config,
                              const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "getaddressesbylabel",
         "Returns the list of addresses assigned the specified label.\n",
         {
             {"label", RPCArg::Type::STR, RPCArg::Optional::NO, "The label."},
         },
         RPCResult{
             "{ (json object with addresses as keys)\n"
             "  \"address\": { (json object with information about address)\n"
             "    \"purpose\": \"string\" (string)  Purpose of address "
             "(\"send\" for sending address, \"receive\" for receiving "
             "address)\n"
             "  },...\n"
             "}\n"},
         RPCExamples{HelpExampleCli("getaddressesbylabel", "\"tabby\"") +
                     HelpExampleRpc("getaddressesbylabel", "\"tabby\"")},
     }
         .Check(request);
 
     LOCK(pwallet->cs_wallet);
 
     std::string label = LabelFromValue(request.params[0]);
 
     // Find all addresses that have the given label
     UniValue ret(UniValue::VOBJ);
     std::set<std::string> addresses;
     for (const std::pair<const CTxDestination, CAddressBookData> &item :
          pwallet->m_address_book) {
         if (item.second.IsChange()) {
             continue;
         }
         if (item.second.GetLabel() == label) {
             std::string address = EncodeDestination(item.first, config);
             // CWallet::m_address_book is not expected to contain duplicate
             // address strings, but build a separate set as a precaution just in
             // case it does.
             bool unique = addresses.emplace(address).second;
             CHECK_NONFATAL(unique);
             // UniValue::pushKV checks if the key exists in O(N)
             // and since duplicate addresses are unexpected (checked with
             // std::set in O(log(N))), UniValue::__pushKV is used instead,
             // which currently is O(1).
             ret.__pushKV(address, AddressBookDataToJSON(item.second, false));
         }
     }
 
     if (ret.empty()) {
         throw JSONRPCError(RPC_WALLET_INVALID_LABEL_NAME,
                            std::string("No addresses with label " + label));
     }
 
     return ret;
 }
 
 UniValue listlabels(const Config &config, const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "listlabels",
         "Returns the list of all labels, or labels that are assigned to "
         "addresses with a specific purpose.\n",
         {
             {"purpose", RPCArg::Type::STR, RPCArg::Optional::OMITTED_NAMED_ARG,
              "Address purpose to list labels for ('send','receive'). An empty "
              "string is the same as not providing this argument."},
         },
         RPCResult{"[               (json array of string)\n"
                   "  \"label\",      (string) Label name\n"
                   "  ...\n"
                   "]\n"},
         RPCExamples{"\nList all labels\n" + HelpExampleCli("listlabels", "") +
                     "\nList labels that have receiving addresses\n" +
                     HelpExampleCli("listlabels", "receive") +
                     "\nList labels that have sending addresses\n" +
                     HelpExampleCli("listlabels", "send") +
                     "\nAs a JSON-RPC call\n" +
                     HelpExampleRpc("listlabels", "receive")},
     }
         .Check(request);
 
     LOCK(pwallet->cs_wallet);
 
     std::string purpose;
     if (!request.params[0].isNull()) {
         purpose = request.params[0].get_str();
     }
 
     // Add to a set to sort by label name, then insert into Univalue array
     std::set<std::string> label_set;
     for (const std::pair<const CTxDestination, CAddressBookData> &entry :
          pwallet->m_address_book) {
         if (entry.second.IsChange()) {
             continue;
         }
         if (purpose.empty() || entry.second.purpose == purpose) {
             label_set.insert(entry.second.GetLabel());
         }
     }
 
     UniValue ret(UniValue::VARR);
     for (const std::string &name : label_set) {
         ret.push_back(name);
     }
 
     return ret;
 }
 
 static UniValue sethdseed(const Config &config, const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "sethdseed",
         "Set or generate a new HD wallet seed. Non-HD wallets will not be "
         "upgraded to being a HD wallet. Wallets that are already\n"
         "HD will have a new HD seed set so that new keys added to the keypool "
         "will be derived from this new seed.\n"
         "\nNote that you will need to MAKE A NEW BACKUP of your wallet after "
         "setting the HD wallet seed.\n" +
             HelpRequiringPassphrase(pwallet) + "\n",
         {
             {"newkeypool", RPCArg::Type::BOOL, /* default */ "true",
              "Whether to flush old unused addresses, including change "
              "addresses, from the keypool and regenerate it.\n"
              "                             If true, the next address from "
              "getnewaddress and change address from getrawchangeaddress will "
              "be from this new seed.\n"
              "                             If false, addresses (including "
              "change addresses if the wallet already had HD Chain Split "
              "enabled) from the existing\n"
              "                             keypool will be used until it has "
              "been depleted."},
             {"seed", RPCArg::Type::STR, /* default */ "random seed",
              "The WIF private key to use as the new HD seed.\n"
              "                             The seed value can be retrieved "
              "using the dumpwallet command. It is the private key marked "
              "hdseed=1"},
         },
         RPCResults{},
         RPCExamples{HelpExampleCli("sethdseed", "") +
                     HelpExampleCli("sethdseed", "false") +
                     HelpExampleCli("sethdseed", "true \"wifkey\"") +
                     HelpExampleRpc("sethdseed", "true, \"wifkey\"")},
     }
         .Check(request);
 
     LegacyScriptPubKeyMan &spk_man =
         EnsureLegacyScriptPubKeyMan(*pwallet, true);
 
     if (pwallet->chain().isInitialBlockDownload()) {
         throw JSONRPCError(
             RPC_CLIENT_IN_INITIAL_DOWNLOAD,
             "Cannot set a new HD seed while still in Initial Block Download");
     }
 
     if (pwallet->IsWalletFlagSet(WALLET_FLAG_DISABLE_PRIVATE_KEYS)) {
         throw JSONRPCError(
             RPC_WALLET_ERROR,
             "Cannot set a HD seed to a wallet with private keys disabled");
     }
 
     auto locked_chain = pwallet->chain().lock();
     LOCK2(pwallet->cs_wallet, spk_man.cs_KeyStore);
 
     // Do not do anything to non-HD wallets
     if (!pwallet->CanSupportFeature(FEATURE_HD)) {
         throw JSONRPCError(
             RPC_WALLET_ERROR,
             "Cannot set a HD seed on a non-HD wallet. Start with "
             "-upgradewallet in order to upgrade a non-HD wallet to HD");
     }
 
     EnsureWalletIsUnlocked(pwallet);
 
     bool flush_key_pool = true;
     if (!request.params[0].isNull()) {
         flush_key_pool = request.params[0].get_bool();
     }
 
     CPubKey master_pub_key;
     if (request.params[1].isNull()) {
         master_pub_key = spk_man.GenerateNewSeed();
     } else {
         CKey key = DecodeSecret(request.params[1].get_str());
         if (!key.IsValid()) {
             throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY,
                                "Invalid private key");
         }
 
         if (HaveKey(spk_man, key)) {
             throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY,
                                "Already have this key (either as an HD seed or "
                                "as a loose private key)");
         }
 
         master_pub_key = spk_man.DeriveNewSeed(key);
     }
 
     spk_man.SetHDSeed(master_pub_key);
     if (flush_key_pool) {
         spk_man.NewKeyPool();
     }
 
     return NullUniValue;
 }
 
 static UniValue walletprocesspsbt(const Config &config,
                                   const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "walletprocesspsbt",
         "Update a PSBT with input information from our wallet and then sign "
         "inputs that we can sign for." +
             HelpRequiringPassphrase(pwallet) + "\n",
         {
             {"psbt", RPCArg::Type::STR, RPCArg::Optional::NO,
              "The transaction base64 string"},
             {"sign", RPCArg::Type::BOOL, /* default */ "true",
              "Also sign the transaction when updating"},
             {"sighashtype", RPCArg::Type::STR, /* default */ "ALL|FORKID",
              "The signature hash type to sign with if not specified by "
              "the PSBT. Must be one of\n"
              "       \"ALL|FORKID\"\n"
              "       \"NONE|FORKID\"\n"
              "       \"SINGLE|FORKID\"\n"
              "       \"ALL|FORKID|ANYONECANPAY\"\n"
              "       \"NONE|FORKID|ANYONECANPAY\"\n"
              "       \"SINGLE|FORKID|ANYONECANPAY\""},
             {"bip32derivs", RPCArg::Type::BOOL, /* default */ "false",
              "If true, includes the BIP 32 derivation paths for public keys if "
              "we know them"},
         },
         RPCResult{"{\n"
                   "  \"psbt\" : \"value\",          (string) The "
                   "base64-encoded partially signed transaction\n"
                   "  \"complete\" : true|false,   (boolean) If the transaction "
                   "has a complete set of signatures\n"
                   "  ]\n"
                   "}\n"},
         RPCExamples{HelpExampleCli("walletprocesspsbt", "\"psbt\"")},
     }
         .Check(request);
 
     RPCTypeCheck(request.params,
                  {UniValue::VSTR, UniValue::VBOOL, UniValue::VSTR});
 
     // Unserialize the transaction
     PartiallySignedTransaction psbtx;
     std::string error;
     if (!DecodeBase64PSBT(psbtx, request.params[0].get_str(), error)) {
         throw JSONRPCError(RPC_DESERIALIZATION_ERROR,
                            strprintf("TX decode failed %s", error));
     }
 
     // Get the sighash type
     SigHashType nHashType = ParseSighashString(request.params[2]);
     if (!nHashType.hasForkId()) {
         throw JSONRPCError(RPC_INVALID_PARAMETER,
                            "Signature must use SIGHASH_FORKID");
     }
 
     // Fill transaction with our data and also sign
     bool sign =
         request.params[1].isNull() ? true : request.params[1].get_bool();
     bool bip32derivs =
         request.params[3].isNull() ? false : request.params[3].get_bool();
     bool complete = true;
     const TransactionError err =
         FillPSBT(pwallet, psbtx, complete, nHashType, sign, bip32derivs);
     if (err != TransactionError::OK) {
         throw JSONRPCTransactionError(err);
     }
 
     UniValue result(UniValue::VOBJ);
     CDataStream ssTx(SER_NETWORK, PROTOCOL_VERSION);
     ssTx << psbtx;
     result.pushKV("psbt", EncodeBase64(ssTx.str()));
     result.pushKV("complete", complete);
 
     return result;
 }
 
 static UniValue walletcreatefundedpsbt(const Config &config,
                                        const JSONRPCRequest &request) {
     std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
     CWallet *const pwallet = wallet.get();
 
     if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
         return NullUniValue;
     }
 
     RPCHelpMan{
         "walletcreatefundedpsbt",
         "Creates and funds a transaction in the Partially Signed Transaction "
         "format. Inputs will be added if supplied inputs are not enough\n"
         "Implements the Creator and Updater roles.\n",
         {
             {
                 "inputs",
                 RPCArg::Type::ARR,
                 RPCArg::Optional::NO,
                 "A json array of json objects",
                 {
                     {
                         "",
                         RPCArg::Type::OBJ,
                         RPCArg::Optional::OMITTED,
                         "",
                         {
                             {"txid", RPCArg::Type::STR_HEX,
                              RPCArg::Optional::NO, "The transaction id"},
                             {"vout", RPCArg::Type::NUM, RPCArg::Optional::NO,
                              "The output number"},
                             {"sequence", RPCArg::Type::NUM,
                              RPCArg::Optional::NO, "The sequence number"},
                         },
                     },
                 },
             },
             {
                 "outputs",
                 RPCArg::Type::ARR,
                 RPCArg::Optional::NO,
                 "a json array with outputs (key-value pairs), where none of "
                 "the keys are duplicated.\n"
                 "That is, each address can only appear once and there can only "
                 "be one 'data' object.\n"
                 "For compatibility reasons, a dictionary, which holds the "
                 "key-value pairs directly, is also\n"
                 "                             accepted as second parameter.",
                 {
                     {
                         "",
                         RPCArg::Type::OBJ,
                         RPCArg::Optional::OMITTED,
                         "",
                         {
                             {"address", RPCArg::Type::AMOUNT,
                              RPCArg::Optional::NO,
                              "A key-value pair. The key (string) is the "
                              "bitcoin address, the value (float or string) is "
                              "the amount in " +
                                  CURRENCY_UNIT + ""},
                         },
                     },
                     {
                         "",
                         RPCArg::Type::OBJ,
                         RPCArg::Optional::OMITTED,
                         "",
                         {
                             {"data", RPCArg::Type::STR_HEX,
                              RPCArg::Optional::NO,
                              "A key-value pair. The key must be \"data\", the "
                              "value is hex-encoded data"},
                         },
                     },
                 },
             },
             {"locktime", RPCArg::Type::NUM, /* default */ "0",
              "Raw locktime. Non-0 value also locktime-activates inputs\n"
              "                             Allows this transaction to be "
              "replaced by a transaction with higher fees. If provided, it is "
              "an error if explicit sequence numbers are incompatible."},
             {"options",
              RPCArg::Type::OBJ,
              RPCArg::Optional::OMITTED_NAMED_ARG,
              "",
              {
                  {"changeAddress", RPCArg::Type::STR_HEX,
                   /* default */ "pool address",
                   "The bitcoin address to receive the change"},
                  {"changePosition", RPCArg::Type::NUM,
                   /* default */ "random", "The index of the change output"},
                  {"includeWatching", RPCArg::Type::BOOL,
                   /* default */ "true for watch-only wallets, otherwise false",
                   "Also select inputs which are watch only"},
                  {"lockUnspents", RPCArg::Type::BOOL, /* default */ "false",
                   "Lock selected unspent outputs"},
                  {"feeRate", RPCArg::Type::AMOUNT, /* default */
                   "not set: makes wallet determine the fee",
                   "Set a specific fee rate in " + CURRENCY_UNIT + "/kB"},
                  {
                      "subtractFeeFromOutputs",
                      RPCArg::Type::ARR,
                      /* default */ "empty array",
                      "A json array of integers.\n"
                      "                              The fee will be equally "
                      "deducted from the amount of each specified output.\n"
                      "                              Those recipients will "
                      "receive less bitcoins than you enter in their "
                      "corresponding amount field.\n"
                      "                              If no outputs are "
                      "specified here, the sender pays the fee.",
                      {
                          {"vout_index", RPCArg::Type::NUM,
                           RPCArg::Optional::OMITTED,
                           "The zero-based output index, before a change output "
                           "is added."},
                      },
                  },
              },
              "options"},
             {"bip32derivs", RPCArg::Type::BOOL, /* default */ "false",
              "If true, includes the BIP 32 derivation paths for public keys if "
              "we know them"},
         },
         RPCResult{"{\n"
                   "  \"psbt\": \"value\",        (string)  The resulting raw "
                   "transaction (base64-encoded string)\n"
                   "  \"fee\":       n,         (numeric) Fee in " +
                   CURRENCY_UNIT +
                   " the resulting transaction pays\n"
                   "  \"changepos\": n          (numeric) The position of the "
                   "added change output, or -1\n"
                   "}\n"},
         RPCExamples{
             "\nCreate a transaction with no inputs\n" +
             HelpExampleCli("walletcreatefundedpsbt",
                            "\"[{\\\"txid\\\":\\\"myid\\\",\\\"vout\\\":0}]\" "
                            "\"[{\\\"data\\\":\\\"00010203\\\"}]\"")},
     }
         .Check(request);
 
     RPCTypeCheck(request.params,
                  {UniValue::VARR,
                   UniValueType(), // ARR or OBJ, checked later
                   UniValue::VNUM, UniValue::VOBJ},
                  true);
 
     Amount fee;
     int change_position;
     CMutableTransaction rawTx =
         ConstructTransaction(wallet->chainParams, request.params[0],
                              request.params[1], request.params[2]);
     FundTransaction(pwallet, rawTx, fee, change_position, request.params[3]);
 
     // Make a blank psbt
     PartiallySignedTransaction psbtx(rawTx);
 
     // Fill transaction with out data but don't sign
     bool bip32derivs =
         request.params[4].isNull() ? false : request.params[4].get_bool();
     bool complete = true;
     const TransactionError err =
         FillPSBT(pwallet, psbtx, complete, SigHashType().withForkId(), false,
                  bip32derivs);
     if (err != TransactionError::OK) {
         throw JSONRPCTransactionError(err);
     }
 
     // Serialize the PSBT
     CDataStream ssTx(SER_NETWORK, PROTOCOL_VERSION);
     ssTx << psbtx;
 
     UniValue result(UniValue::VOBJ);
     result.pushKV("psbt", EncodeBase64(ssTx.str()));
     result.pushKV("fee", ValueFromAmount(fee));
     result.pushKV("changepos", change_position);
     return result;
 }
 
 // clang-format off
 static const CRPCCommand commands[] = {
     //  category            name                            actor (function)              argNames
     //  ------------------- ------------------------        ----------------------        ----------
     { "rawtransactions",    "fundrawtransaction",           fundrawtransaction,           {"hexstring","options"} },
     { "wallet",             "abandontransaction",           abandontransaction,           {"txid"} },
     { "wallet",             "addmultisigaddress",           addmultisigaddress,           {"nrequired","keys","label"} },
     { "wallet",             "backupwallet",                 backupwallet,                 {"destination"} },
     { "wallet",             "createwallet",                 createwallet,                 {"wallet_name", "disable_private_keys", "blank", "passphrase", "avoid_reuse"} },
     { "wallet",             "encryptwallet",                encryptwallet,                {"passphrase"} },
     { "wallet",             "getaddressesbylabel",          getaddressesbylabel,          {"label"} },
     { "wallet",             "getaddressinfo",               getaddressinfo,               {"address"} },
     { "wallet",             "getbalance",                   getbalance,                   {"dummy","minconf","include_watchonly","avoid_reuse"} },
     { "wallet",             "getnewaddress",                getnewaddress,                {"label", "address_type"} },
     { "wallet",             "getrawchangeaddress",          getrawchangeaddress,          {"address_type"} },
     { "wallet",             "getreceivedbyaddress",         getreceivedbyaddress,         {"address","minconf"} },
     { "wallet",             "getreceivedbylabel",           getreceivedbylabel,           {"label","minconf"} },
     { "wallet",             "gettransaction",               gettransaction,               {"txid","include_watchonly","verbose"} },
     { "wallet",             "getunconfirmedbalance",        getunconfirmedbalance,        {} },
     { "wallet",             "getbalances",                  getbalances,                  {} },
     { "wallet",             "getwalletinfo",                getwalletinfo,                {} },
     { "wallet",             "keypoolrefill",                keypoolrefill,                {"newsize"} },
     { "wallet",             "listaddressgroupings",         listaddressgroupings,         {} },
     { "wallet",             "listlabels",                   listlabels,                   {"purpose"} },
     { "wallet",             "listlockunspent",              listlockunspent,              {} },
     { "wallet",             "listreceivedbyaddress",        listreceivedbyaddress,        {"minconf","include_empty","include_watchonly","address_filter"} },
     { "wallet",             "listreceivedbylabel",          listreceivedbylabel,          {"minconf","include_empty","include_watchonly"} },
     { "wallet",             "listsinceblock",               listsinceblock,               {"blockhash","target_confirmations","include_watchonly","include_removed"} },
     { "wallet",             "listtransactions",             listtransactions,             {"label|dummy","count","skip","include_watchonly"} },
     { "wallet",             "listunspent",                  listunspent,                  {"minconf","maxconf","addresses","include_unsafe","query_options"} },
     { "wallet",             "listwalletdir",                listwalletdir,                {} },
     { "wallet",             "listwallets",                  listwallets,                  {} },
     { "wallet",             "loadwallet",                   loadwallet,                   {"filename"} },
     { "wallet",             "lockunspent",                  lockunspent,                  {"unlock","transactions"} },
     { "wallet",             "rescanblockchain",             rescanblockchain,             {"start_height", "stop_height"} },
     { "wallet",             "sendmany",                     sendmany,                     {"dummy","amounts","minconf","comment","subtractfeefrom"} },
     { "wallet",             "sendtoaddress",                sendtoaddress,                {"address","amount","comment","comment_to","subtractfeefromamount","avoid_reuse"} },
     { "wallet",             "sethdseed",                    sethdseed,                    {"newkeypool","seed"} },
     { "wallet",             "setlabel",                     setlabel,                     {"address","label"} },
     { "wallet",             "settxfee",                     settxfee,                     {"amount"} },
     { "wallet",             "setwalletflag",                setwalletflag,                {"flag","value"} },
     { "wallet",             "signmessage",                  signmessage,                  {"address","message"} },
     { "wallet",             "signrawtransactionwithwallet", signrawtransactionwithwallet, {"hextring","prevtxs","sighashtype"} },
     { "wallet",             "unloadwallet",                 unloadwallet,                 {"wallet_name"} },
     { "wallet",             "walletcreatefundedpsbt",       walletcreatefundedpsbt,       {"inputs","outputs","locktime","options","bip32derivs"} },
     { "wallet",             "walletlock",                   walletlock,                   {} },
     { "wallet",             "walletpassphrase",             walletpassphrase,             {"passphrase","timeout"} },
     { "wallet",             "walletpassphrasechange",       walletpassphrasechange,       {"oldpassphrase","newpassphrase"} },
     { "wallet",             "walletprocesspsbt",            walletprocesspsbt,            {"psbt","sign","sighashtype","bip32derivs"} },
 };
 // clang-format on
 
 void RegisterWalletRPCCommands(
     interfaces::Chain &chain,
     std::vector<std::unique_ptr<interfaces::Handler>> &handlers) {
     for (unsigned int vcidx = 0; vcidx < ARRAYLEN(commands); vcidx++) {
         handlers.emplace_back(chain.handleRpc(commands[vcidx]));
     }
 }
 
 interfaces::Chain *g_rpc_chain = nullptr;
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index e700cf62b..a9aa4c49e 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -1,4776 +1,4774 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
 // Copyright (c) 2009-2019 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <wallet/wallet.h>
 
 #include <chain.h>
 #include <chainparams.h>
 #include <config.h>
 #include <consensus/consensus.h>
 #include <consensus/validation.h>
 #include <fs.h>
 #include <interfaces/wallet.h>
 #include <key.h>
 #include <key_io.h>
 #include <optional.h>
 #include <policy/mempool.h>
 #include <policy/policy.h>
 #include <primitives/transaction.h>
 #include <random.h>
 #include <script/descriptor.h>
 #include <script/script.h>
 #include <script/sighashtype.h>
 #include <script/sign.h>
 #include <script/signingprovider.h>
 #include <util/bip32.h>
+#include <util/check.h>
 #include <util/error.h>
 #include <util/moneystr.h>
 #include <util/string.h>
 #include <util/translation.h>
 #include <util/validation.h>
 #include <wallet/coincontrol.h>
 #include <wallet/fees.h>
 
 #include <boost/algorithm/string/replace.hpp>
 
-#include <cassert>
+using interfaces::FoundBlock;
 
 const std::map<uint64_t, std::string> WALLET_FLAG_CAVEATS{
     {WALLET_FLAG_AVOID_REUSE,
      "You need to rescan the blockchain in order to correctly mark used "
      "destinations in the past. Until this is done, some destinations may "
      "be considered unused, even if the opposite is the case."},
 };
 
 static RecursiveMutex cs_wallets;
 static std::vector<std::shared_ptr<CWallet>> vpwallets GUARDED_BY(cs_wallets);
 static std::list<LoadWalletFn> g_load_wallet_fns GUARDED_BY(cs_wallets);
 
 bool AddWallet(const std::shared_ptr<CWallet> &wallet) {
     LOCK(cs_wallets);
     assert(wallet);
     std::vector<std::shared_ptr<CWallet>>::const_iterator i =
         std::find(vpwallets.begin(), vpwallets.end(), wallet);
     if (i != vpwallets.end()) {
         return false;
     }
     vpwallets.push_back(wallet);
     wallet->ConnectScriptPubKeyManNotifiers();
     return true;
 }
 
 bool RemoveWallet(const std::shared_ptr<CWallet> &wallet) {
     assert(wallet);
     // Unregister with the validation interface which also drops shared ponters.
     wallet->m_chain_notifications_handler.reset();
     LOCK(cs_wallets);
     std::vector<std::shared_ptr<CWallet>>::iterator i =
         std::find(vpwallets.begin(), vpwallets.end(), wallet);
     if (i == vpwallets.end()) {
         return false;
     }
     vpwallets.erase(i);
     return true;
 }
 
 bool HasWallets() {
     LOCK(cs_wallets);
     return !vpwallets.empty();
 }
 
 std::vector<std::shared_ptr<CWallet>> GetWallets() {
     LOCK(cs_wallets);
     return vpwallets;
 }
 
 std::shared_ptr<CWallet> GetWallet(const std::string &name) {
     LOCK(cs_wallets);
     for (const std::shared_ptr<CWallet> &wallet : vpwallets) {
         if (wallet->GetName() == name) {
             return wallet;
         }
     }
     return nullptr;
 }
 
 std::unique_ptr<interfaces::Handler>
 HandleLoadWallet(LoadWalletFn load_wallet) {
     LOCK(cs_wallets);
     auto it = g_load_wallet_fns.emplace(g_load_wallet_fns.end(),
                                         std::move(load_wallet));
     return interfaces::MakeHandler([it] {
         LOCK(cs_wallets);
         g_load_wallet_fns.erase(it);
     });
 }
 
 static Mutex g_wallet_release_mutex;
 static std::condition_variable g_wallet_release_cv;
 static std::set<std::string> g_unloading_wallet_set;
 
 // Custom deleter for shared_ptr<CWallet>.
 static void ReleaseWallet(CWallet *wallet) {
     const std::string name = wallet->GetName();
     wallet->WalletLogPrintf("Releasing wallet\n");
     wallet->Flush();
     delete wallet;
     // Wallet is now released, notify UnloadWallet, if any.
     {
         LOCK(g_wallet_release_mutex);
         if (g_unloading_wallet_set.erase(name) == 0) {
             // UnloadWallet was not called for this wallet, all done.
             return;
         }
     }
     g_wallet_release_cv.notify_all();
 }
 
 void UnloadWallet(std::shared_ptr<CWallet> &&wallet) {
     // Mark wallet for unloading.
     const std::string name = wallet->GetName();
     {
         LOCK(g_wallet_release_mutex);
         auto it = g_unloading_wallet_set.insert(name);
         assert(it.second);
     }
     // The wallet can be in use so it's not possible to explicitly unload here.
     // Notify the unload intent so that all remaining shared pointers are
     // released.
     wallet->NotifyUnload();
 
     // Time to ditch our shared_ptr and wait for ReleaseWallet call.
     wallet.reset();
     {
         WAIT_LOCK(g_wallet_release_mutex, lock);
         while (g_unloading_wallet_set.count(name) == 1) {
             g_wallet_release_cv.wait(lock);
         }
     }
 }
 
 static const size_t OUTPUT_GROUP_MAX_ENTRIES = 10;
 
 std::shared_ptr<CWallet> LoadWallet(const CChainParams &chainParams,
                                     interfaces::Chain &chain,
                                     const WalletLocation &location,
                                     bilingual_str &error,
                                     std::vector<bilingual_str> &warnings) {
     if (!CWallet::Verify(chainParams, chain, location, false, error,
                          warnings)) {
         error = Untranslated("Wallet file verification failed.") +
                 Untranslated(" ") + error;
         return nullptr;
     }
 
     std::shared_ptr<CWallet> wallet = CWallet::CreateWalletFromFile(
         chainParams, chain, location, error, warnings);
     if (!wallet) {
         error =
             Untranslated("Wallet loading failed.") + Untranslated(" ") + error;
         return nullptr;
     }
     AddWallet(wallet);
     wallet->postInitProcess();
     return wallet;
 }
 
 std::shared_ptr<CWallet> LoadWallet(const CChainParams &chainParams,
                                     interfaces::Chain &chain,
                                     const std::string &name,
                                     bilingual_str &error,
                                     std::vector<bilingual_str> &warnings) {
     return LoadWallet(chainParams, chain, WalletLocation(name), error,
                       warnings);
 }
 
 WalletCreationStatus CreateWallet(const CChainParams &params,
                                   interfaces::Chain &chain,
                                   const SecureString &passphrase,
                                   uint64_t wallet_creation_flags,
                                   const std::string &name, bilingual_str &error,
                                   std::vector<bilingual_str> &warnings,
                                   std::shared_ptr<CWallet> &result) {
     // Indicate that the wallet is actually supposed to be blank and not just
     // blank to make it encrypted
     bool create_blank = (wallet_creation_flags & WALLET_FLAG_BLANK_WALLET);
 
     // Born encrypted wallets need to be created blank first.
     if (!passphrase.empty()) {
         wallet_creation_flags |= WALLET_FLAG_BLANK_WALLET;
     }
 
     // Check the wallet file location
     WalletLocation location(name);
     if (location.Exists()) {
         error = strprintf(Untranslated("Wallet %s already exists."),
                           location.GetName());
         return WalletCreationStatus::CREATION_FAILED;
     }
 
     // Wallet::Verify will check if we're trying to create a wallet with a
     // duplicate name.
     if (!CWallet::Verify(params, chain, location, false, error, warnings)) {
         error = Untranslated("Wallet file verification failed.") +
                 Untranslated(" ") + error;
         return WalletCreationStatus::CREATION_FAILED;
     }
 
     // Do not allow a passphrase when private keys are disabled
     if (!passphrase.empty() &&
         (wallet_creation_flags & WALLET_FLAG_DISABLE_PRIVATE_KEYS)) {
         error = Untranslated(
             "Passphrase provided but private keys are disabled. A passphrase "
             "is only used to encrypt private keys, so cannot be used for "
             "wallets with private keys disabled.");
         return WalletCreationStatus::CREATION_FAILED;
     }
 
     // Make the wallet
     std::shared_ptr<CWallet> wallet = CWallet::CreateWalletFromFile(
         params, chain, location, error, warnings, wallet_creation_flags);
     if (!wallet) {
         error =
             Untranslated("Wallet creation failed.") + Untranslated(" ") + error;
         return WalletCreationStatus::CREATION_FAILED;
     }
 
     // Encrypt the wallet
     if (!passphrase.empty() &&
         !(wallet_creation_flags & WALLET_FLAG_DISABLE_PRIVATE_KEYS)) {
         if (!wallet->EncryptWallet(passphrase)) {
             error =
                 Untranslated("Error: Wallet created but failed to encrypt.");
             return WalletCreationStatus::ENCRYPTION_FAILED;
         }
         if (!create_blank) {
             // Unlock the wallet
             if (!wallet->Unlock(passphrase)) {
                 error = Untranslated(
                     "Error: Wallet was encrypted but could not be unlocked");
                 return WalletCreationStatus::ENCRYPTION_FAILED;
             }
 
             // Set a seed for the wallet
             {
                 LOCK(wallet->cs_wallet);
                 for (auto spk_man : wallet->GetActiveScriptPubKeyMans()) {
                     if (!spk_man->SetupGeneration()) {
                         error = Untranslated("Unable to generate initial keys");
                         return WalletCreationStatus::CREATION_FAILED;
                     }
                 }
             }
 
             // Relock the wallet
             wallet->Lock();
         }
     }
     AddWallet(wallet);
     wallet->postInitProcess();
     result = wallet;
     return WalletCreationStatus::SUCCESS;
 }
 
 const BlockHash CWalletTx::ABANDON_HASH(UINT256_ONE());
 
 /** @defgroup mapWallet
  *
  * @{
  */
 
 std::string COutput::ToString() const {
     return strprintf("COutput(%s, %d, %d) [%s]", tx->GetId().ToString(), i,
                      nDepth, FormatMoney(tx->tx->vout[i].nValue));
 }
 
 const CWalletTx *CWallet::GetWalletTx(const TxId &txid) const {
     LOCK(cs_wallet);
     std::map<TxId, CWalletTx>::const_iterator it = mapWallet.find(txid);
     if (it == mapWallet.end()) {
         return nullptr;
     }
 
     return &(it->second);
 }
 
 void CWallet::UpgradeKeyMetadata() {
     if (IsLocked() || IsWalletFlagSet(WALLET_FLAG_KEY_ORIGIN_METADATA)) {
         return;
     }
 
     auto spk_man = GetLegacyScriptPubKeyMan();
     if (!spk_man) {
         return;
     }
 
     spk_man->UpgradeKeyMetadata();
     SetWalletFlag(WALLET_FLAG_KEY_ORIGIN_METADATA);
 }
 
 bool CWallet::Unlock(const SecureString &strWalletPassphrase,
                      bool accept_no_keys) {
     CCrypter crypter;
     CKeyingMaterial _vMasterKey;
 
     {
         LOCK(cs_wallet);
         for (const MasterKeyMap::value_type &pMasterKey : mapMasterKeys) {
             if (!crypter.SetKeyFromPassphrase(
                     strWalletPassphrase, pMasterKey.second.vchSalt,
                     pMasterKey.second.nDeriveIterations,
                     pMasterKey.second.nDerivationMethod)) {
                 return false;
             }
             if (!crypter.Decrypt(pMasterKey.second.vchCryptedKey,
                                  _vMasterKey)) {
                 // try another master key
                 continue;
             }
             if (Unlock(_vMasterKey, accept_no_keys)) {
                 // Now that we've unlocked, upgrade the key metadata
                 UpgradeKeyMetadata();
                 return true;
             }
         }
     }
 
     return false;
 }
 
 bool CWallet::ChangeWalletPassphrase(
     const SecureString &strOldWalletPassphrase,
     const SecureString &strNewWalletPassphrase) {
     bool fWasLocked = IsLocked();
 
     LOCK(cs_wallet);
     Lock();
 
     CCrypter crypter;
     CKeyingMaterial _vMasterKey;
     for (MasterKeyMap::value_type &pMasterKey : mapMasterKeys) {
         if (!crypter.SetKeyFromPassphrase(
                 strOldWalletPassphrase, pMasterKey.second.vchSalt,
                 pMasterKey.second.nDeriveIterations,
                 pMasterKey.second.nDerivationMethod)) {
             return false;
         }
 
         if (!crypter.Decrypt(pMasterKey.second.vchCryptedKey, _vMasterKey)) {
             return false;
         }
 
         if (Unlock(_vMasterKey)) {
             int64_t nStartTime = GetTimeMillis();
             crypter.SetKeyFromPassphrase(strNewWalletPassphrase,
                                          pMasterKey.second.vchSalt,
                                          pMasterKey.second.nDeriveIterations,
                                          pMasterKey.second.nDerivationMethod);
             pMasterKey.second.nDeriveIterations = static_cast<unsigned int>(
                 pMasterKey.second.nDeriveIterations *
                 (100 / ((double)(GetTimeMillis() - nStartTime))));
 
             nStartTime = GetTimeMillis();
             crypter.SetKeyFromPassphrase(strNewWalletPassphrase,
                                          pMasterKey.second.vchSalt,
                                          pMasterKey.second.nDeriveIterations,
                                          pMasterKey.second.nDerivationMethod);
             pMasterKey.second.nDeriveIterations =
                 (pMasterKey.second.nDeriveIterations +
                  static_cast<unsigned int>(
                      pMasterKey.second.nDeriveIterations * 100 /
                      double(GetTimeMillis() - nStartTime))) /
                 2;
 
             if (pMasterKey.second.nDeriveIterations < 25000) {
                 pMasterKey.second.nDeriveIterations = 25000;
             }
 
             WalletLogPrintf(
                 "Wallet passphrase changed to an nDeriveIterations of %i\n",
                 pMasterKey.second.nDeriveIterations);
 
             if (!crypter.SetKeyFromPassphrase(
                     strNewWalletPassphrase, pMasterKey.second.vchSalt,
                     pMasterKey.second.nDeriveIterations,
                     pMasterKey.second.nDerivationMethod)) {
                 return false;
             }
 
             if (!crypter.Encrypt(_vMasterKey,
                                  pMasterKey.second.vchCryptedKey)) {
                 return false;
             }
 
             WalletBatch(*database).WriteMasterKey(pMasterKey.first,
                                                   pMasterKey.second);
             if (fWasLocked) {
                 Lock();
             }
 
             return true;
         }
     }
 
     return false;
 }
 
 void CWallet::ChainStateFlushed(const CBlockLocator &loc) {
     WalletBatch batch(*database);
     batch.WriteBestBlock(loc);
 }
 
 void CWallet::SetMinVersion(enum WalletFeature nVersion, WalletBatch *batch_in,
                             bool fExplicit) {
     LOCK(cs_wallet);
     if (nWalletVersion >= nVersion) {
         return;
     }
 
     // When doing an explicit upgrade, if we pass the max version permitted,
     // upgrade all the way.
     if (fExplicit && nVersion > nWalletMaxVersion) {
         nVersion = FEATURE_LATEST;
     }
 
     nWalletVersion = nVersion;
 
     if (nVersion > nWalletMaxVersion) {
         nWalletMaxVersion = nVersion;
     }
 
     WalletBatch *batch = batch_in ? batch_in : new WalletBatch(*database);
     if (nWalletVersion > 40000) {
         batch->WriteMinVersion(nWalletVersion);
     }
     if (!batch_in) {
         delete batch;
     }
 }
 
 bool CWallet::SetMaxVersion(int nVersion) {
     LOCK(cs_wallet);
 
     // Cannot downgrade below current version
     if (nWalletVersion > nVersion) {
         return false;
     }
 
     nWalletMaxVersion = nVersion;
 
     return true;
 }
 
 std::set<TxId> CWallet::GetConflicts(const TxId &txid) const {
     std::set<TxId> result;
     AssertLockHeld(cs_wallet);
 
     std::map<TxId, CWalletTx>::const_iterator it = mapWallet.find(txid);
     if (it == mapWallet.end()) {
         return result;
     }
 
     const CWalletTx &wtx = it->second;
 
     std::pair<TxSpends::const_iterator, TxSpends::const_iterator> range;
 
     for (const CTxIn &txin : wtx.tx->vin) {
         if (mapTxSpends.count(txin.prevout) <= 1) {
             // No conflict if zero or one spends.
             continue;
         }
 
         range = mapTxSpends.equal_range(txin.prevout);
         for (TxSpends::const_iterator _it = range.first; _it != range.second;
              ++_it) {
             result.insert(_it->second);
         }
     }
 
     return result;
 }
 
 bool CWallet::HasWalletSpend(const TxId &txid) const {
     AssertLockHeld(cs_wallet);
     auto iter = mapTxSpends.lower_bound(COutPoint(txid, 0));
     return (iter != mapTxSpends.end() && iter->first.GetTxId() == txid);
 }
 
 void CWallet::Flush(bool shutdown) {
     database->Flush(shutdown);
 }
 
 void CWallet::SyncMetaData(
     std::pair<TxSpends::iterator, TxSpends::iterator> range) {
     // We want all the wallet transactions in range to have the same metadata as
     // the oldest (smallest nOrderPos).
     // So: find smallest nOrderPos:
 
     int nMinOrderPos = std::numeric_limits<int>::max();
     const CWalletTx *copyFrom = nullptr;
     for (TxSpends::iterator it = range.first; it != range.second; ++it) {
         const CWalletTx *wtx = &mapWallet.at(it->second);
         if (wtx->nOrderPos < nMinOrderPos) {
             nMinOrderPos = wtx->nOrderPos;
             copyFrom = wtx;
         }
     }
 
     if (!copyFrom) {
         return;
     }
 
     // Now copy data from copyFrom to rest:
     for (TxSpends::iterator it = range.first; it != range.second; ++it) {
         const TxId &txid = it->second;
         CWalletTx *copyTo = &mapWallet.at(txid);
         if (copyFrom == copyTo) {
             continue;
         }
 
         assert(
             copyFrom &&
             "Oldest wallet transaction in range assumed to have been found.");
 
         if (!copyFrom->IsEquivalentTo(*copyTo)) {
             continue;
         }
 
         copyTo->mapValue = copyFrom->mapValue;
         copyTo->vOrderForm = copyFrom->vOrderForm;
         // fTimeReceivedIsTxTime not copied on purpose nTimeReceived not copied
         // on purpose.
         copyTo->nTimeSmart = copyFrom->nTimeSmart;
         copyTo->fFromMe = copyFrom->fFromMe;
         // nOrderPos not copied on purpose cached members not copied on purpose.
     }
 }
 
 /**
  * Outpoint is spent if any non-conflicted transaction, spends it:
  */
 bool CWallet::IsSpent(const COutPoint &outpoint) const {
     std::pair<TxSpends::const_iterator, TxSpends::const_iterator> range =
         mapTxSpends.equal_range(outpoint);
 
     for (TxSpends::const_iterator it = range.first; it != range.second; ++it) {
         const TxId &wtxid = it->second;
         std::map<TxId, CWalletTx>::const_iterator mit = mapWallet.find(wtxid);
         if (mit != mapWallet.end()) {
             int depth = mit->second.GetDepthInMainChain();
             if (depth > 0 || (depth == 0 && !mit->second.isAbandoned())) {
                 // Spent
                 return true;
             }
         }
     }
 
     return false;
 }
 
 void CWallet::AddToSpends(const COutPoint &outpoint, const TxId &wtxid) {
     mapTxSpends.insert(std::make_pair(outpoint, wtxid));
 
     setLockedCoins.erase(outpoint);
 
     std::pair<TxSpends::iterator, TxSpends::iterator> range;
     range = mapTxSpends.equal_range(outpoint);
     SyncMetaData(range);
 }
 
 void CWallet::AddToSpends(const TxId &wtxid) {
     auto it = mapWallet.find(wtxid);
     assert(it != mapWallet.end());
     CWalletTx &thisTx = it->second;
     // Coinbases don't spend anything!
     if (thisTx.IsCoinBase()) {
         return;
     }
 
     for (const CTxIn &txin : thisTx.tx->vin) {
         AddToSpends(txin.prevout, wtxid);
     }
 }
 
 bool CWallet::EncryptWallet(const SecureString &strWalletPassphrase) {
     if (IsCrypted()) {
         return false;
     }
 
     CKeyingMaterial _vMasterKey;
 
     _vMasterKey.resize(WALLET_CRYPTO_KEY_SIZE);
     GetStrongRandBytes(&_vMasterKey[0], WALLET_CRYPTO_KEY_SIZE);
 
     CMasterKey kMasterKey;
 
     kMasterKey.vchSalt.resize(WALLET_CRYPTO_SALT_SIZE);
     GetStrongRandBytes(&kMasterKey.vchSalt[0], WALLET_CRYPTO_SALT_SIZE);
 
     CCrypter crypter;
     int64_t nStartTime = GetTimeMillis();
     crypter.SetKeyFromPassphrase(strWalletPassphrase, kMasterKey.vchSalt, 25000,
                                  kMasterKey.nDerivationMethod);
     kMasterKey.nDeriveIterations = static_cast<unsigned int>(
         2500000 / double(GetTimeMillis() - nStartTime));
 
     nStartTime = GetTimeMillis();
     crypter.SetKeyFromPassphrase(strWalletPassphrase, kMasterKey.vchSalt,
                                  kMasterKey.nDeriveIterations,
                                  kMasterKey.nDerivationMethod);
     kMasterKey.nDeriveIterations =
         (kMasterKey.nDeriveIterations +
          static_cast<unsigned int>(kMasterKey.nDeriveIterations * 100 /
                                    double(GetTimeMillis() - nStartTime))) /
         2;
 
     if (kMasterKey.nDeriveIterations < 25000) {
         kMasterKey.nDeriveIterations = 25000;
     }
 
     WalletLogPrintf("Encrypting Wallet with an nDeriveIterations of %i\n",
                     kMasterKey.nDeriveIterations);
 
     if (!crypter.SetKeyFromPassphrase(strWalletPassphrase, kMasterKey.vchSalt,
                                       kMasterKey.nDeriveIterations,
                                       kMasterKey.nDerivationMethod)) {
         return false;
     }
 
     if (!crypter.Encrypt(_vMasterKey, kMasterKey.vchCryptedKey)) {
         return false;
     }
 
     {
         LOCK(cs_wallet);
         mapMasterKeys[++nMasterKeyMaxID] = kMasterKey;
         WalletBatch *encrypted_batch = new WalletBatch(*database);
         if (!encrypted_batch->TxnBegin()) {
             delete encrypted_batch;
             encrypted_batch = nullptr;
             return false;
         }
         encrypted_batch->WriteMasterKey(nMasterKeyMaxID, kMasterKey);
 
         for (const auto &spk_man_pair : m_spk_managers) {
             auto spk_man = spk_man_pair.second.get();
             if (!spk_man->Encrypt(_vMasterKey, encrypted_batch)) {
                 encrypted_batch->TxnAbort();
                 delete encrypted_batch;
                 encrypted_batch = nullptr;
                 // We now probably have half of our keys encrypted in memory,
                 // and half not... die and let the user reload the unencrypted
                 // wallet.
                 assert(false);
             }
         }
 
         // Encryption was introduced in version 0.4.0
         SetMinVersion(FEATURE_WALLETCRYPT, encrypted_batch, true);
 
         if (!encrypted_batch->TxnCommit()) {
             delete encrypted_batch;
             encrypted_batch = nullptr;
             // We now have keys encrypted in memory, but not on disk...
             // die to avoid confusion and let the user reload the unencrypted
             // wallet.
             assert(false);
         }
 
         delete encrypted_batch;
         encrypted_batch = nullptr;
 
         Lock();
         Unlock(strWalletPassphrase);
 
         // if we are using HD, replace the HD seed with a new one
         if (auto spk_man = GetLegacyScriptPubKeyMan()) {
             if (spk_man->IsHDEnabled()) {
                 if (!spk_man->SetupGeneration(true)) {
                     return false;
                 }
             }
         }
         Lock();
 
         // Need to completely rewrite the wallet file; if we don't, bdb might
         // keep bits of the unencrypted private key in slack space in the
         // database file.
         database->Rewrite();
 
         // BDB seems to have a bad habit of writing old data into
         // slack space in .dat files; that is bad if the old data is
         // unencrypted private keys. So:
         database->ReloadDbEnv();
     }
 
     NotifyStatusChanged(this);
     return true;
 }
 
 DBErrors CWallet::ReorderTransactions() {
     LOCK(cs_wallet);
     WalletBatch batch(*database);
 
     // Old wallets didn't have any defined order for transactions. Probably a
     // bad idea to change the output of this.
 
     // First: get all CWalletTx into a sorted-by-time
     // multimap.
     TxItems txByTime;
 
     for (auto &entry : mapWallet) {
         CWalletTx *wtx = &entry.second;
         txByTime.insert(std::make_pair(wtx->nTimeReceived, wtx));
     }
 
     nOrderPosNext = 0;
     std::vector<int64_t> nOrderPosOffsets;
     for (TxItems::iterator it = txByTime.begin(); it != txByTime.end(); ++it) {
         CWalletTx *const pwtx = (*it).second;
         int64_t &nOrderPos = pwtx->nOrderPos;
 
         if (nOrderPos == -1) {
             nOrderPos = nOrderPosNext++;
             nOrderPosOffsets.push_back(nOrderPos);
 
             if (!batch.WriteTx(*pwtx)) {
                 return DBErrors::LOAD_FAIL;
             }
         } else {
             int64_t nOrderPosOff = 0;
             for (const int64_t &nOffsetStart : nOrderPosOffsets) {
                 if (nOrderPos >= nOffsetStart) {
                     ++nOrderPosOff;
                 }
             }
 
             nOrderPos += nOrderPosOff;
             nOrderPosNext = std::max(nOrderPosNext, nOrderPos + 1);
 
             if (!nOrderPosOff) {
                 continue;
             }
 
             // Since we're changing the order, write it back.
             if (!batch.WriteTx(*pwtx)) {
                 return DBErrors::LOAD_FAIL;
             }
         }
     }
 
     batch.WriteOrderPosNext(nOrderPosNext);
 
     return DBErrors::LOAD_OK;
 }
 
 int64_t CWallet::IncOrderPosNext(WalletBatch *batch) {
     AssertLockHeld(cs_wallet);
     int64_t nRet = nOrderPosNext++;
     if (batch) {
         batch->WriteOrderPosNext(nOrderPosNext);
     } else {
         WalletBatch(*database).WriteOrderPosNext(nOrderPosNext);
     }
 
     return nRet;
 }
 
 void CWallet::MarkDirty() {
     LOCK(cs_wallet);
     for (std::pair<const TxId, CWalletTx> &item : mapWallet) {
         item.second.MarkDirty();
     }
 }
 
 void CWallet::SetUsedDestinationState(
     WalletBatch &batch, const TxId &txid, unsigned int n, bool used,
     std::set<CTxDestination> &tx_destinations) {
     AssertLockHeld(cs_wallet);
     const CWalletTx *srctx = GetWalletTx(txid);
     if (!srctx) {
         return;
     }
 
     CTxDestination dst;
     if (ExtractDestination(srctx->tx->vout[n].scriptPubKey, dst)) {
         if (IsMine(dst)) {
             if (used && !GetDestData(dst, "used", nullptr)) {
                 // p for "present", opposite of absent (null)
                 if (AddDestData(batch, dst, "used", "p")) {
                     tx_destinations.insert(dst);
                 }
             } else if (!used && GetDestData(dst, "used", nullptr)) {
                 EraseDestData(batch, dst, "used");
             }
         }
     }
 }
 
 bool CWallet::IsUsedDestination(const TxId &txid, unsigned int n) const {
     AssertLockHeld(cs_wallet);
     CTxDestination dst;
     const CWalletTx *srctx = GetWalletTx(txid);
     if (srctx) {
         assert(srctx->tx->vout.size() > n);
         LegacyScriptPubKeyMan *spk_man = GetLegacyScriptPubKeyMan();
         // When descriptor wallets arrive, these additional checks are
         // likely superfluous and can be optimized out
         assert(spk_man != nullptr);
         for (const auto &keyid :
              GetAffectedKeys(srctx->tx->vout[n].scriptPubKey, *spk_man)) {
             PKHash pkh_dest(keyid);
             if (GetDestData(pkh_dest, "used", nullptr)) {
                 return true;
             }
         }
     }
     return false;
 }
 
 bool CWallet::AddToWallet(const CWalletTx &wtxIn, bool fFlushOnClose) {
     LOCK(cs_wallet);
 
     WalletBatch batch(*database, "r+", fFlushOnClose);
 
     const TxId &txid = wtxIn.GetId();
 
     if (IsWalletFlagSet(WALLET_FLAG_AVOID_REUSE)) {
         // Mark used destinations
         std::set<CTxDestination> tx_destinations;
 
         for (const CTxIn &txin : wtxIn.tx->vin) {
             const COutPoint &op = txin.prevout;
             SetUsedDestinationState(batch, op.GetTxId(), op.GetN(), true,
                                     tx_destinations);
         }
 
         MarkDestinationsDirty(tx_destinations);
     }
 
     // Inserts only if not already there, returns tx inserted or tx found.
     std::pair<std::map<TxId, CWalletTx>::iterator, bool> ret =
         mapWallet.insert(std::make_pair(txid, wtxIn));
     CWalletTx &wtx = (*ret.first).second;
     wtx.BindWallet(this);
     bool fInsertedNew = ret.second;
     if (fInsertedNew) {
         wtx.nTimeReceived = chain().getAdjustedTime();
         wtx.nOrderPos = IncOrderPosNext(&batch);
         wtx.m_it_wtxOrdered =
             wtxOrdered.insert(std::make_pair(wtx.nOrderPos, &wtx));
         wtx.nTimeSmart = ComputeTimeSmart(wtx);
         AddToSpends(txid);
     }
 
     bool fUpdated = false;
     if (!fInsertedNew) {
         if (wtxIn.m_confirm.status != wtx.m_confirm.status) {
             wtx.m_confirm.status = wtxIn.m_confirm.status;
             wtx.m_confirm.nIndex = wtxIn.m_confirm.nIndex;
             wtx.m_confirm.hashBlock = wtxIn.m_confirm.hashBlock;
             wtx.m_confirm.block_height = wtxIn.m_confirm.block_height;
             fUpdated = true;
         } else {
             assert(wtx.m_confirm.nIndex == wtxIn.m_confirm.nIndex);
             assert(wtx.m_confirm.hashBlock == wtxIn.m_confirm.hashBlock);
             assert(wtx.m_confirm.block_height == wtxIn.m_confirm.block_height);
         }
 
         if (wtxIn.fFromMe && wtxIn.fFromMe != wtx.fFromMe) {
             wtx.fFromMe = wtxIn.fFromMe;
             fUpdated = true;
         }
     }
 
     //// debug print
     WalletLogPrintf("AddToWallet %s  %s%s\n", wtxIn.GetId().ToString(),
                     (fInsertedNew ? "new" : ""), (fUpdated ? "update" : ""));
 
     // Write to disk
     if ((fInsertedNew || fUpdated) && !batch.WriteTx(wtx)) {
         return false;
     }
 
     // Break debit/credit balance caches:
     wtx.MarkDirty();
 
     // Notify UI of new or updated transaction.
     NotifyTransactionChanged(this, txid, fInsertedNew ? CT_NEW : CT_UPDATED);
 
 #if defined(HAVE_SYSTEM)
     // Notify an external script when a wallet transaction comes in or is
     // updated.
     std::string strCmd = gArgs.GetArg("-walletnotify", "");
 
     if (!strCmd.empty()) {
         boost::replace_all(strCmd, "%s", wtxIn.GetId().GetHex());
         std::thread t(runCommand, strCmd);
         // Thread runs free.
         t.detach();
     }
 #endif
 
     return true;
 }
 
 void CWallet::LoadToWallet(CWalletTx &wtxIn) {
     // If wallet doesn't have a chain (e.g bitcoin-wallet), lock can't be taken.
     auto locked_chain = LockChain();
     if (locked_chain) {
         Optional<int> block_height =
             locked_chain->getBlockHeight(wtxIn.m_confirm.hashBlock);
         if (block_height) {
             // Update cached block height variable since it not stored in the
             // serialized transaction.
             wtxIn.m_confirm.block_height = *block_height;
         } else if (wtxIn.isConflicted() || wtxIn.isConfirmed()) {
             // If tx block (or conflicting block) was reorged out of chain
             // while the wallet was shutdown, change tx status to UNCONFIRMED
             // and reset block height, hash, and index. ABANDONED tx don't have
             // associated blocks and don't need to be updated. The case where a
             // transaction was reorged out while online and then reconfirmed
             // while offline is covered by the rescan logic.
             wtxIn.setUnconfirmed();
             wtxIn.m_confirm.hashBlock = BlockHash();
             wtxIn.m_confirm.block_height = 0;
             wtxIn.m_confirm.nIndex = 0;
         }
     }
     const TxId &txid = wtxIn.GetId();
     const auto &ins = mapWallet.emplace(txid, wtxIn);
     CWalletTx &wtx = ins.first->second;
     wtx.BindWallet(this);
     if (/* insertion took place */ ins.second) {
         wtx.m_it_wtxOrdered =
             wtxOrdered.insert(std::make_pair(wtx.nOrderPos, &wtx));
     }
     AddToSpends(txid);
     for (const CTxIn &txin : wtx.tx->vin) {
         auto it = mapWallet.find(txin.prevout.GetTxId());
         if (it != mapWallet.end()) {
             CWalletTx &prevtx = it->second;
             if (prevtx.isConflicted()) {
                 MarkConflicted(prevtx.m_confirm.hashBlock,
                                prevtx.m_confirm.block_height, wtx.GetId());
             }
         }
     }
 }
 
 bool CWallet::AddToWalletIfInvolvingMe(const CTransactionRef &ptx,
                                        CWalletTx::Confirmation confirm,
                                        bool fUpdate) {
     const CTransaction &tx = *ptx;
     AssertLockHeld(cs_wallet);
 
     if (!confirm.hashBlock.IsNull()) {
         for (const CTxIn &txin : tx.vin) {
             std::pair<TxSpends::const_iterator, TxSpends::const_iterator>
                 range = mapTxSpends.equal_range(txin.prevout);
             while (range.first != range.second) {
                 if (range.first->second != tx.GetId()) {
                     WalletLogPrintf(
                         "Transaction %s (in block %s) conflicts with wallet "
                         "transaction %s (both spend %s:%i)\n",
                         tx.GetId().ToString(), confirm.hashBlock.ToString(),
                         range.first->second.ToString(),
                         range.first->first.GetTxId().ToString(),
                         range.first->first.GetN());
                     MarkConflicted(confirm.hashBlock, confirm.block_height,
                                    range.first->second);
                 }
                 range.first++;
             }
         }
     }
 
     bool fExisted = mapWallet.count(tx.GetId()) != 0;
     if (fExisted && !fUpdate) {
         return false;
     }
     if (fExisted || IsMine(tx) || IsFromMe(tx)) {
         /**
          * Check if any keys in the wallet keypool that were supposed to be
          * unused have appeared in a new transaction. If so, remove those keys
          * from the keypool. This can happen when restoring an old wallet backup
          * that does not contain the mostly recently created transactions from
          * newer versions of the wallet.
          */
 
         // loop though all outputs
         for (const CTxOut &txout : tx.vout) {
             for (const auto &spk_man_pair : m_spk_managers) {
                 spk_man_pair.second->MarkUnusedAddresses(txout.scriptPubKey);
             }
         }
 
         CWalletTx wtx(this, ptx);
 
         // Block disconnection override an abandoned tx as unconfirmed
         // which means user may have to call abandontransaction again
         wtx.m_confirm = confirm;
 
         return AddToWallet(wtx, false);
     }
 
     return false;
 }
 
 bool CWallet::TransactionCanBeAbandoned(const TxId &txid) const {
     auto locked_chain = chain().lock();
     LOCK(cs_wallet);
     const CWalletTx *wtx = GetWalletTx(txid);
     return wtx && !wtx->isAbandoned() && wtx->GetDepthInMainChain() == 0 &&
            !wtx->InMempool();
 }
 
 void CWallet::MarkInputsDirty(const CTransactionRef &tx) {
     for (const CTxIn &txin : tx->vin) {
         auto it = mapWallet.find(txin.prevout.GetTxId());
         if (it != mapWallet.end()) {
             it->second.MarkDirty();
         }
     }
 }
 
 bool CWallet::AbandonTransaction(const TxId &txid) {
     // Temporary. Removed in upcoming lock cleanup
     auto locked_chain = chain().lock();
     LOCK(cs_wallet);
 
     WalletBatch batch(*database, "r+");
 
     std::set<TxId> todo;
     std::set<TxId> done;
 
     // Can't mark abandoned if confirmed or in mempool
     auto it = mapWallet.find(txid);
     assert(it != mapWallet.end());
     CWalletTx &origtx = it->second;
     if (origtx.GetDepthInMainChain() != 0 || origtx.InMempool()) {
         return false;
     }
 
     todo.insert(txid);
 
     while (!todo.empty()) {
         const TxId now = *todo.begin();
         todo.erase(now);
         done.insert(now);
         it = mapWallet.find(now);
         assert(it != mapWallet.end());
         CWalletTx &wtx = it->second;
         int currentconfirm = wtx.GetDepthInMainChain();
         // If the orig tx was not in block, none of its spends can be.
         assert(currentconfirm <= 0);
         // If (currentconfirm < 0) {Tx and spends are already conflicted, no
         // need to abandon}
         if (currentconfirm == 0 && !wtx.isAbandoned()) {
             // If the orig tx was not in block/mempool, none of its spends can
             // be in mempool.
             assert(!wtx.InMempool());
             wtx.setAbandoned();
             wtx.MarkDirty();
             batch.WriteTx(wtx);
             NotifyTransactionChanged(this, wtx.GetId(), CT_UPDATED);
             // Iterate over all its outputs, and mark transactions in the wallet
             // that spend them abandoned too.
             TxSpends::const_iterator iter =
                 mapTxSpends.lower_bound(COutPoint(now, 0));
             while (iter != mapTxSpends.end() && iter->first.GetTxId() == now) {
                 if (!done.count(iter->second)) {
                     todo.insert(iter->second);
                 }
                 iter++;
             }
 
             // If a transaction changes 'conflicted' state, that changes the
             // balance available of the outputs it spends. So force those to be
             // recomputed.
             MarkInputsDirty(wtx.tx);
         }
     }
 
     return true;
 }
 
 void CWallet::MarkConflicted(const BlockHash &hashBlock, int conflicting_height,
                              const TxId &txid) {
     auto locked_chain = chain().lock();
     LOCK(cs_wallet);
 
     int conflictconfirms =
         (m_last_block_processed_height - conflicting_height + 1) * -1;
 
     // If number of conflict confirms cannot be determined, this means that the
     // block is still unknown or not yet part of the main chain, for example
     // when loading the wallet during a reindex. Do nothing in that case.
     if (conflictconfirms >= 0) {
         return;
     }
 
     // Do not flush the wallet here for performance reasons.
     WalletBatch batch(*database, "r+", false);
 
     std::set<TxId> todo;
     std::set<TxId> done;
 
     todo.insert(txid);
 
     while (!todo.empty()) {
         const TxId now = *todo.begin();
         todo.erase(now);
         done.insert(now);
         auto it = mapWallet.find(now);
         assert(it != mapWallet.end());
         CWalletTx &wtx = it->second;
         int currentconfirm = wtx.GetDepthInMainChain();
         if (conflictconfirms < currentconfirm) {
             // Block is 'more conflicted' than current confirm; update.
             // Mark transaction as conflicted with this block.
             wtx.m_confirm.nIndex = 0;
             wtx.m_confirm.hashBlock = hashBlock;
             wtx.m_confirm.block_height = conflicting_height;
             wtx.setConflicted();
             wtx.MarkDirty();
             batch.WriteTx(wtx);
             // Iterate over all its outputs, and mark transactions in the wallet
             // that spend them conflicted too.
             TxSpends::const_iterator iter =
                 mapTxSpends.lower_bound(COutPoint(now, 0));
             while (iter != mapTxSpends.end() && iter->first.GetTxId() == now) {
                 if (!done.count(iter->second)) {
                     todo.insert(iter->second);
                 }
                 iter++;
             }
             // If a transaction changes 'conflicted' state, that changes the
             // balance available of the outputs it spends. So force those to be
             // recomputed.
             MarkInputsDirty(wtx.tx);
         }
     }
 }
 
 void CWallet::SyncTransaction(const CTransactionRef &ptx,
                               CWalletTx::Confirmation confirm, bool update_tx) {
     if (!AddToWalletIfInvolvingMe(ptx, confirm, update_tx)) {
         // Not one of ours
         return;
     }
 
     // If a transaction changes 'conflicted' state, that changes the balance
     // available of the outputs it spends. So force those to be
     // recomputed, also:
     MarkInputsDirty(ptx);
 }
 
 void CWallet::TransactionAddedToMempool(const CTransactionRef &ptx) {
     auto locked_chain = chain().lock();
     LOCK(cs_wallet);
     CWalletTx::Confirmation confirm(CWalletTx::Status::UNCONFIRMED,
                                     /* block_height */ 0, BlockHash(),
                                     /* nIndex */ 0);
     SyncTransaction(ptx, confirm);
 
     auto it = mapWallet.find(ptx->GetId());
     if (it != mapWallet.end()) {
         it->second.fInMempool = true;
     }
 }
 
 void CWallet::TransactionRemovedFromMempool(const CTransactionRef &ptx) {
     LOCK(cs_wallet);
     auto it = mapWallet.find(ptx->GetId());
     if (it != mapWallet.end()) {
         it->second.fInMempool = false;
     }
 }
 
 void CWallet::BlockConnected(const CBlock &block,
                              const std::vector<CTransactionRef> &vtxConflicted,
                              int height) {
     const BlockHash &block_hash = block.GetHash();
     auto locked_chain = chain().lock();
     LOCK(cs_wallet);
 
     m_last_block_processed_height = height;
     m_last_block_processed = block_hash;
     for (size_t index = 0; index < block.vtx.size(); index++) {
         CWalletTx::Confirmation confirm(CWalletTx::Status::CONFIRMED, height,
                                         block_hash, index);
         SyncTransaction(block.vtx[index], confirm);
         TransactionRemovedFromMempool(block.vtx[index]);
     }
     for (const CTransactionRef &ptx : vtxConflicted) {
         TransactionRemovedFromMempool(ptx);
     }
 }
 
 void CWallet::BlockDisconnected(const CBlock &block, int height) {
     auto locked_chain = chain().lock();
     LOCK(cs_wallet);
 
     // At block disconnection, this will change an abandoned transaction to
     // be unconfirmed, whether or not the transaction is added back to the
     // mempool. User may have to call abandontransaction again. It may be
     // addressed in the future with a stickier abandoned state or even removing
     // abandontransaction call.
     m_last_block_processed_height = height - 1;
     m_last_block_processed = block.hashPrevBlock;
     for (const CTransactionRef &ptx : block.vtx) {
         CWalletTx::Confirmation confirm(CWalletTx::Status::UNCONFIRMED,
                                         /* block_height */ 0, BlockHash(),
                                         /* nIndex */ 0);
         SyncTransaction(ptx, confirm);
     }
 }
 
 void CWallet::UpdatedBlockTip() {
     m_best_block_time = GetTime();
 }
 
 void CWallet::BlockUntilSyncedToCurrentChain() {
     AssertLockNotHeld(cs_wallet);
     // Skip the queue-draining stuff if we know we're caught up with
     // chainActive.Tip(), otherwise put a callback in the validation interface
     // queue and wait for the queue to drain enough to execute it (indicating we
     // are caught up at least with the time we entered this function).
     const BlockHash last_block_hash =
         WITH_LOCK(cs_wallet, return m_last_block_processed);
     chain().waitForNotificationsIfTipChanged(last_block_hash);
 }
 
 isminetype CWallet::IsMine(const CTxIn &txin) const {
     LOCK(cs_wallet);
     std::map<TxId, CWalletTx>::const_iterator mi =
         mapWallet.find(txin.prevout.GetTxId());
     if (mi != mapWallet.end()) {
         const CWalletTx &prev = (*mi).second;
         if (txin.prevout.GetN() < prev.tx->vout.size()) {
             return IsMine(prev.tx->vout[txin.prevout.GetN()]);
         }
     }
 
     return ISMINE_NO;
 }
 
 // Note that this function doesn't distinguish between a 0-valued input, and a
 // not-"is mine" (according to the filter) input.
 Amount CWallet::GetDebit(const CTxIn &txin, const isminefilter &filter) const {
     LOCK(cs_wallet);
     std::map<TxId, CWalletTx>::const_iterator mi =
         mapWallet.find(txin.prevout.GetTxId());
     if (mi != mapWallet.end()) {
         const CWalletTx &prev = (*mi).second;
         if (txin.prevout.GetN() < prev.tx->vout.size()) {
             if (IsMine(prev.tx->vout[txin.prevout.GetN()]) & filter) {
                 return prev.tx->vout[txin.prevout.GetN()].nValue;
             }
         }
     }
 
     return Amount::zero();
 }
 
 isminetype CWallet::IsMine(const CTxOut &txout) const {
     return IsMine(txout.scriptPubKey);
 }
 
 isminetype CWallet::IsMine(const CTxDestination &dest) const {
     return IsMine(GetScriptForDestination(dest));
 }
 
 isminetype CWallet::IsMine(const CScript &script) const {
     isminetype result = ISMINE_NO;
     for (const auto &spk_man_pair : m_spk_managers) {
         result = std::max(result, spk_man_pair.second->IsMine(script));
     }
     return result;
 }
 
 Amount CWallet::GetCredit(const CTxOut &txout,
                           const isminefilter &filter) const {
     if (!MoneyRange(txout.nValue)) {
         throw std::runtime_error(std::string(__func__) +
                                  ": value out of range");
     }
 
     return (IsMine(txout) & filter) ? txout.nValue : Amount::zero();
 }
 
 bool CWallet::IsChange(const CTxOut &txout) const {
     return IsChange(txout.scriptPubKey);
 }
 
 bool CWallet::IsChange(const CScript &script) const {
     // TODO: fix handling of 'change' outputs. The assumption is that any
     // payment to a script that is ours, but is not in the address book is
     // change. That assumption is likely to break when we implement
     // multisignature wallets that return change back into a
     // multi-signature-protected address; a better way of identifying which
     // outputs are 'the send' and which are 'the change' will need to be
     // implemented (maybe extend CWalletTx to remember which output, if any, was
     // change).
     if (IsMine(script)) {
         CTxDestination address;
         if (!ExtractDestination(script, address)) {
             return true;
         }
 
         LOCK(cs_wallet);
         if (!FindAddressBookEntry(address)) {
             return true;
         }
     }
 
     return false;
 }
 
 Amount CWallet::GetChange(const CTxOut &txout) const {
     if (!MoneyRange(txout.nValue)) {
         throw std::runtime_error(std::string(__func__) +
                                  ": value out of range");
     }
 
     return (IsChange(txout) ? txout.nValue : Amount::zero());
 }
 
 bool CWallet::IsMine(const CTransaction &tx) const {
     for (const CTxOut &txout : tx.vout) {
         if (IsMine(txout)) {
             return true;
         }
     }
 
     return false;
 }
 
 bool CWallet::IsFromMe(const CTransaction &tx) const {
     return GetDebit(tx, ISMINE_ALL) > Amount::zero();
 }
 
 Amount CWallet::GetDebit(const CTransaction &tx,
                          const isminefilter &filter) const {
     Amount nDebit = Amount::zero();
     for (const CTxIn &txin : tx.vin) {
         nDebit += GetDebit(txin, filter);
         if (!MoneyRange(nDebit)) {
             throw std::runtime_error(std::string(__func__) +
                                      ": value out of range");
         }
     }
 
     return nDebit;
 }
 
 bool CWallet::IsAllFromMe(const CTransaction &tx,
                           const isminefilter &filter) const {
     LOCK(cs_wallet);
 
     for (const CTxIn &txin : tx.vin) {
         auto mi = mapWallet.find(txin.prevout.GetTxId());
         if (mi == mapWallet.end()) {
             // Any unknown inputs can't be from us.
             return false;
         }
 
         const CWalletTx &prev = (*mi).second;
 
         if (txin.prevout.GetN() >= prev.tx->vout.size()) {
             // Invalid input!
             return false;
         }
 
         if (!(IsMine(prev.tx->vout[txin.prevout.GetN()]) & filter)) {
             return false;
         }
     }
 
     return true;
 }
 
 Amount CWallet::GetCredit(const CTransaction &tx,
                           const isminefilter &filter) const {
     Amount nCredit = Amount::zero();
     for (const CTxOut &txout : tx.vout) {
         nCredit += GetCredit(txout, filter);
         if (!MoneyRange(nCredit)) {
             throw std::runtime_error(std::string(__func__) +
                                      ": value out of range");
         }
     }
 
     return nCredit;
 }
 
 Amount CWallet::GetChange(const CTransaction &tx) const {
     Amount nChange = Amount::zero();
     for (const CTxOut &txout : tx.vout) {
         nChange += GetChange(txout);
         if (!MoneyRange(nChange)) {
             throw std::runtime_error(std::string(__func__) +
                                      ": value out of range");
         }
     }
 
     return nChange;
 }
 
 bool CWallet::IsHDEnabled() const {
     bool result = true;
     for (const auto &spk_man_pair : m_spk_managers) {
         result &= spk_man_pair.second->IsHDEnabled();
     }
     return result;
 }
 
 bool CWallet::CanGetAddresses(bool internal) {
     LOCK(cs_wallet);
     if (m_spk_managers.empty()) {
         return false;
     }
     for (OutputType t : OUTPUT_TYPES) {
         auto spk_man = GetScriptPubKeyMan(t, internal);
         if (spk_man && spk_man->CanGetAddresses(internal)) {
             return true;
         }
     }
     return false;
 }
 
 void CWallet::SetWalletFlag(uint64_t flags) {
     LOCK(cs_wallet);
     m_wallet_flags |= flags;
     if (!WalletBatch(*database).WriteWalletFlags(m_wallet_flags)) {
         throw std::runtime_error(std::string(__func__) +
                                  ": writing wallet flags failed");
     }
 }
 
 void CWallet::UnsetWalletFlag(uint64_t flag) {
     WalletBatch batch(*database);
     UnsetWalletFlagWithDB(batch, flag);
 }
 
 void CWallet::UnsetWalletFlagWithDB(WalletBatch &batch, uint64_t flag) {
     LOCK(cs_wallet);
     m_wallet_flags &= ~flag;
     if (!batch.WriteWalletFlags(m_wallet_flags)) {
         throw std::runtime_error(std::string(__func__) +
                                  ": writing wallet flags failed");
     }
 }
 
 void CWallet::UnsetBlankWalletFlag(WalletBatch &batch) {
     UnsetWalletFlagWithDB(batch, WALLET_FLAG_BLANK_WALLET);
 }
 
 bool CWallet::IsWalletFlagSet(uint64_t flag) const {
     return (m_wallet_flags & flag);
 }
 
 bool CWallet::SetWalletFlags(uint64_t overwriteFlags, bool memonly) {
     LOCK(cs_wallet);
     m_wallet_flags = overwriteFlags;
     if (((overwriteFlags & KNOWN_WALLET_FLAGS) >> 32) ^
         (overwriteFlags >> 32)) {
         // contains unknown non-tolerable wallet flags
         return false;
     }
     if (!memonly && !WalletBatch(*database).WriteWalletFlags(m_wallet_flags)) {
         throw std::runtime_error(std::string(__func__) +
                                  ": writing wallet flags failed");
     }
 
     return true;
 }
 
 int64_t CWalletTx::GetTxTime() const {
     int64_t n = nTimeSmart;
     return n ? n : nTimeReceived;
 }
 
 // Helper for producing a max-sized low-S low-R signature (eg 71 bytes)
 // or a max-sized low-S signature (e.g. 72 bytes) if use_max_sig is true
 bool CWallet::DummySignInput(CTxIn &tx_in, const CTxOut &txout,
                              bool use_max_sig) const {
     // Fill in dummy signatures for fee calculation.
     const CScript &scriptPubKey = txout.scriptPubKey;
     SignatureData sigdata;
 
     std::unique_ptr<SigningProvider> provider =
         GetSigningProvider(scriptPubKey);
     if (!provider) {
         // We don't know about this scriptpbuKey;
         return false;
     }
 
     if (!ProduceSignature(*provider,
                           use_max_sig ? DUMMY_MAXIMUM_SIGNATURE_CREATOR
                                       : DUMMY_SIGNATURE_CREATOR,
                           scriptPubKey, sigdata)) {
         return false;
     }
 
     UpdateInput(tx_in, sigdata);
     return true;
 }
 
 // Helper for producing a bunch of max-sized low-S low-R signatures (eg 71
 // bytes)
 bool CWallet::DummySignTx(CMutableTransaction &txNew,
                           const std::vector<CTxOut> &txouts,
                           bool use_max_sig) const {
     // Fill in dummy signatures for fee calculation.
     int nIn = 0;
     for (const auto &txout : txouts) {
         if (!DummySignInput(txNew.vin[nIn], txout, use_max_sig)) {
             return false;
         }
 
         nIn++;
     }
     return true;
 }
 
 bool CWallet::ImportScripts(const std::set<CScript> scripts,
                             int64_t timestamp) {
     auto spk_man = GetLegacyScriptPubKeyMan();
     if (!spk_man) {
         return false;
     }
     LOCK(spk_man->cs_KeyStore);
     return spk_man->ImportScripts(scripts, timestamp);
 }
 
 bool CWallet::ImportPrivKeys(const std::map<CKeyID, CKey> &privkey_map,
                              const int64_t timestamp) {
     auto spk_man = GetLegacyScriptPubKeyMan();
     if (!spk_man) {
         return false;
     }
     LOCK(spk_man->cs_KeyStore);
     return spk_man->ImportPrivKeys(privkey_map, timestamp);
 }
 
 bool CWallet::ImportPubKeys(
     const std::vector<CKeyID> &ordered_pubkeys,
     const std::map<CKeyID, CPubKey> &pubkey_map,
     const std::map<CKeyID, std::pair<CPubKey, KeyOriginInfo>> &key_origins,
     const bool add_keypool, const bool internal, const int64_t timestamp) {
     auto spk_man = GetLegacyScriptPubKeyMan();
     if (!spk_man) {
         return false;
     }
     LOCK(spk_man->cs_KeyStore);
     return spk_man->ImportPubKeys(ordered_pubkeys, pubkey_map, key_origins,
                                   add_keypool, internal, timestamp);
 }
 
 bool CWallet::ImportScriptPubKeys(const std::string &label,
                                   const std::set<CScript> &script_pub_keys,
                                   const bool have_solving_data,
                                   const bool apply_label,
                                   const int64_t timestamp) {
     auto spk_man = GetLegacyScriptPubKeyMan();
     if (!spk_man) {
         return false;
     }
     LOCK(spk_man->cs_KeyStore);
     if (!spk_man->ImportScriptPubKeys(script_pub_keys, have_solving_data,
                                       timestamp)) {
         return false;
     }
     if (apply_label) {
         WalletBatch batch(*database);
         for (const CScript &script : script_pub_keys) {
             CTxDestination dest;
             ExtractDestination(script, dest);
             if (IsValidDestination(dest)) {
                 SetAddressBookWithDB(batch, dest, label, "receive");
             }
         }
     }
     return true;
 }
 
 int64_t CalculateMaximumSignedTxSize(const CTransaction &tx,
                                      const CWallet *wallet, bool use_max_sig) {
     std::vector<CTxOut> txouts;
     for (auto &input : tx.vin) {
         const auto mi = wallet->mapWallet.find(input.prevout.GetTxId());
         // Can not estimate size without knowing the input details
         if (mi == wallet->mapWallet.end()) {
             return -1;
         }
         assert(input.prevout.GetN() < mi->second.tx->vout.size());
         txouts.emplace_back(mi->second.tx->vout[input.prevout.GetN()]);
     }
     return CalculateMaximumSignedTxSize(tx, wallet, txouts, use_max_sig);
 }
 
 // txouts needs to be in the order of tx.vin
 int64_t CalculateMaximumSignedTxSize(const CTransaction &tx,
                                      const CWallet *wallet,
                                      const std::vector<CTxOut> &txouts,
                                      bool use_max_sig) {
     CMutableTransaction txNew(tx);
     if (!wallet->DummySignTx(txNew, txouts, use_max_sig)) {
         return -1;
     }
     return GetSerializeSize(txNew, PROTOCOL_VERSION);
 }
 
 int CalculateMaximumSignedInputSize(const CTxOut &txout, const CWallet *wallet,
                                     bool use_max_sig) {
     CMutableTransaction txn;
     txn.vin.push_back(CTxIn(COutPoint()));
     if (!wallet->DummySignInput(txn.vin[0], txout, use_max_sig)) {
         // This should never happen, because IsAllFromMe(ISMINE_SPENDABLE)
         // implies that we can sign for every input.
         return -1;
     }
     return GetSerializeSize(txn.vin[0], PROTOCOL_VERSION);
 }
 
 void CWalletTx::GetAmounts(std::list<COutputEntry> &listReceived,
                            std::list<COutputEntry> &listSent, Amount &nFee,
                            const isminefilter &filter) const {
     nFee = Amount::zero();
     listReceived.clear();
     listSent.clear();
 
     // Compute fee:
     Amount nDebit = GetDebit(filter);
     // debit>0 means we signed/sent this transaction.
     if (nDebit > Amount::zero()) {
         Amount nValueOut = tx->GetValueOut();
         nFee = (nDebit - nValueOut);
     }
 
     // Sent/received.
     for (unsigned int i = 0; i < tx->vout.size(); ++i) {
         const CTxOut &txout = tx->vout[i];
         isminetype fIsMine = pwallet->IsMine(txout);
         // Only need to handle txouts if AT LEAST one of these is true:
         //   1) they debit from us (sent)
         //   2) the output is to us (received)
         if (nDebit > Amount::zero()) {
             // Don't report 'change' txouts
             if (pwallet->IsChange(txout)) {
                 continue;
             }
         } else if (!(fIsMine & filter)) {
             continue;
         }
 
         // In either case, we need to get the destination address.
         CTxDestination address;
 
         if (!ExtractDestination(txout.scriptPubKey, address) &&
             !txout.scriptPubKey.IsUnspendable()) {
             pwallet->WalletLogPrintf("CWalletTx::GetAmounts: Unknown "
                                      "transaction type found, txid %s\n",
                                      this->GetId().ToString());
             address = CNoDestination();
         }
 
         COutputEntry output = {address, txout.nValue, (int)i};
 
         // If we are debited by the transaction, add the output as a "sent"
         // entry.
         if (nDebit > Amount::zero()) {
             listSent.push_back(output);
         }
 
         // If we are receiving the output, add it as a "received" entry.
         if (fIsMine & filter) {
             listReceived.push_back(output);
         }
     }
 }
 
 /**
  * Scan active chain for relevant transactions after importing keys. This should
  * be called whenever new keys are added to the wallet, with the oldest key
  * creation time.
  *
  * @return Earliest timestamp that could be successfully scanned from. Timestamp
  * returned will be higher than startTime if relevant blocks could not be read.
  */
 int64_t CWallet::RescanFromTime(int64_t startTime,
                                 const WalletRescanReserver &reserver,
                                 bool update) {
     // Find starting block. May be null if nCreateTime is greater than the
     // highest blockchain timestamp, in which case there is nothing that needs
     // to be scanned.
     BlockHash start_block;
     {
         auto locked_chain = chain().lock();
         const Optional<int> start_height =
             locked_chain->findFirstBlockWithTimeAndHeight(
                 startTime - TIMESTAMP_WINDOW, 0, &start_block);
         const Optional<int> tip_height = locked_chain->getHeight();
         WalletLogPrintf(
             "%s: Rescanning last %i blocks\n", __func__,
             tip_height && start_height ? *tip_height - *start_height + 1 : 0);
     }
 
     if (!start_block.IsNull()) {
         // TODO: this should take into account failure by ScanResult::USER_ABORT
         ScanResult result = ScanForWalletTransactions(start_block, BlockHash(),
                                                       reserver, update);
         if (result.status == ScanResult::FAILURE) {
             int64_t time_max;
-            if (!chain().findBlock(result.last_failed_block,
-                                   nullptr /* block */, nullptr /* time */,
-                                   &time_max)) {
-                throw std::logic_error(
-                    "ScanForWalletTransactions returned invalid block hash");
-            }
+            CHECK_NONFATAL(chain().findBlock(result.last_failed_block,
+                                             FoundBlock().maxTime(time_max)));
             return time_max + TIMESTAMP_WINDOW + 1;
         }
     }
     return startTime;
 }
 
 /**
  * Scan the block chain (starting in start_block) for transactions from or to
  * us. If fUpdate is true, found transactions that already exist in the wallet
  * will be updated.
  *
  * @param[in] start_block Scan starting block. If block is not on the active
  *                        chain, the scan will return SUCCESS immediately.
  * @param[in] stop_block  Scan ending block. If block is not on the active
  *                        chain, the scan will continue until it reaches the
  *                        chain tip.
  *
  * @return ScanResult returning scan information and indicating success or
  *         failure. Return status will be set to SUCCESS if scan was
  *         successful. FAILURE if a complete rescan was not possible (due to
  *         pruning or corruption). USER_ABORT if the rescan was aborted before
  *         it could complete.
  *
  * @pre Caller needs to make sure start_block (and the optional stop_block) are
  * on the main chain after to the addition of any new keys you want to detect
  * transactions for.
  */
 CWallet::ScanResult CWallet::ScanForWalletTransactions(
     const BlockHash &start_block, const BlockHash &stop_block,
     const WalletRescanReserver &reserver, bool fUpdate) {
     int64_t nNow = GetTime();
     int64_t start_time = GetTimeMillis();
 
     assert(reserver.isReserved());
 
     BlockHash block_hash = start_block;
     ScanResult result;
 
     WalletLogPrintf("Rescan started from block %s...\n",
                     start_block.ToString());
 
     fAbortRescan = false;
 
     // Show rescan progress in GUI as dialog or on splashscreen, if -rescan
     // on startup.
     ShowProgress(
         strprintf("%s " + _("Rescanning...").translated, GetDisplayName()), 0);
     BlockHash tip_hash;
     // The way the 'block_height' is initialized is just a workaround for
     // the gcc bug #47679 since version 4.6.0.
     Optional<int> block_height = MakeOptional(false, int());
     double progress_begin;
     double progress_end;
     {
         auto locked_chain = chain().lock();
         if (Optional<int> tip_height = locked_chain->getHeight()) {
             tip_hash = locked_chain->getBlockHash(*tip_height);
         }
         block_height = locked_chain->getBlockHeight(block_hash);
         progress_begin = chain().guessVerificationProgress(block_hash);
         progress_end = chain().guessVerificationProgress(
             stop_block.IsNull() ? tip_hash : stop_block);
     }
     double progress_current = progress_begin;
     while (block_height && !fAbortRescan && !chain().shutdownRequested()) {
         m_scanning_progress = (progress_current - progress_begin) /
                               (progress_end - progress_begin);
         if (*block_height % 100 == 0 && progress_end - progress_begin > 0.0) {
             ShowProgress(
                 strprintf("%s " + _("Rescanning...").translated,
                           GetDisplayName()),
                 std::max(1, std::min(99, int(m_scanning_progress * 100))));
         }
         if (GetTime() >= nNow + 60) {
             nNow = GetTime();
             WalletLogPrintf("Still rescanning. At block %d. Progress=%f\n",
                             *block_height, progress_current);
         }
 
         CBlock block;
-        if (chain().findBlock(block_hash, &block) && !block.IsNull()) {
+        if (chain().findBlock(block_hash, FoundBlock().data(block)) &&
+            !block.IsNull()) {
             auto locked_chain = chain().lock();
             LOCK(cs_wallet);
             if (!locked_chain->getBlockHeight(block_hash)) {
                 // Abort scan if current block is no longer active, to
                 // prevent marking transactions as coming from the wrong
                 // block.
                 // TODO: This should return success instead of failure, see
                 // https://github.com/bitcoin/bitcoin/pull/14711#issuecomment-458342518
                 result.last_failed_block = block_hash;
                 result.status = ScanResult::FAILURE;
                 break;
             }
             for (size_t posInBlock = 0; posInBlock < block.vtx.size();
                  ++posInBlock) {
                 CWalletTx::Confirmation confirm(CWalletTx::Status::CONFIRMED,
                                                 *block_height, block_hash,
                                                 posInBlock);
                 SyncTransaction(block.vtx[posInBlock], confirm, fUpdate);
             }
             // scan succeeded, record block as most recent successfully
             // scanned
             result.last_scanned_block = block_hash;
             result.last_scanned_height = *block_height;
         } else {
             // could not scan block, keep scanning but record this block as
             // the most recent failure
             result.last_failed_block = block_hash;
             result.status = ScanResult::FAILURE;
         }
         if (block_hash == stop_block) {
             break;
         }
         {
             auto locked_chain = chain().lock();
             Optional<int> tip_height = locked_chain->getHeight();
             if (!tip_height || *tip_height <= block_height ||
                 !locked_chain->getBlockHeight(block_hash)) {
                 // break successfully when rescan has reached the tip, or
                 // previous block is no longer on the chain due to a reorg
                 break;
             }
 
             // increment block and verification progress
             block_hash = locked_chain->getBlockHash(++*block_height);
             progress_current = chain().guessVerificationProgress(block_hash);
 
             // handle updated tip hash
             const BlockHash prev_tip_hash = tip_hash;
             tip_hash = locked_chain->getBlockHash(*tip_height);
             if (stop_block.IsNull() && prev_tip_hash != tip_hash) {
                 // in case the tip has changed, update progress max
                 progress_end = chain().guessVerificationProgress(tip_hash);
             }
         }
     }
 
     // Hide progress dialog in GUI.
     ShowProgress(
         strprintf("%s " + _("Rescanning...").translated, GetDisplayName()),
         100);
     if (block_height && fAbortRescan) {
         WalletLogPrintf("Rescan aborted at block %d. Progress=%f\n",
                         *block_height, progress_current);
         result.status = ScanResult::USER_ABORT;
     } else if (block_height && chain().shutdownRequested()) {
         WalletLogPrintf("Rescan interrupted by shutdown request at block "
                         "%d. Progress=%f\n",
                         *block_height, progress_current);
         result.status = ScanResult::USER_ABORT;
     } else {
         WalletLogPrintf("Rescan completed in %15dms\n",
                         GetTimeMillis() - start_time);
     }
     return result;
 }
 
 void CWallet::ReacceptWalletTransactions() {
     // If transactions aren't being broadcasted, don't let them into local
     // mempool either.
     if (!fBroadcastTransactions) {
         return;
     }
 
     std::map<int64_t, CWalletTx *> mapSorted;
 
     // Sort pending wallet transactions based on their initial wallet insertion
     // order.
     for (std::pair<const TxId, CWalletTx> &item : mapWallet) {
         const TxId &wtxid = item.first;
         CWalletTx &wtx = item.second;
         assert(wtx.GetId() == wtxid);
 
         int nDepth = wtx.GetDepthInMainChain();
 
         if (!wtx.IsCoinBase() && (nDepth == 0 && !wtx.isAbandoned())) {
             mapSorted.insert(std::make_pair(wtx.nOrderPos, &wtx));
         }
     }
 
     // Try to add wallet transactions to memory pool.
     for (const std::pair<const int64_t, CWalletTx *> &item : mapSorted) {
         CWalletTx &wtx = *(item.second);
         std::string unused_err_string;
         wtx.SubmitMemoryPoolAndRelay(unused_err_string, false);
     }
 }
 
 bool CWalletTx::SubmitMemoryPoolAndRelay(std::string &err_string, bool relay) {
     // Can't relay if wallet is not broadcasting
     if (!pwallet->GetBroadcastTransactions()) {
         return false;
     }
     // Don't relay abandoned transactions
     if (isAbandoned()) {
         return false;
     }
     // Don't try to submit coinbase transactions. These would fail anyway but
     // would cause log spam.
     if (IsCoinBase()) {
         return false;
     }
     // Don't try to submit conflicted or confirmed transactions.
     if (GetDepthInMainChain() != 0) {
         return false;
     }
 
     // Submit transaction to mempool for relay
     pwallet->WalletLogPrintf("Submitting wtx %s to mempool for relay\n",
                              GetId().ToString());
     // We must set fInMempool here - while it will be re-set to true by the
     // entered-mempool callback, if we did not there would be a race where a
     // user could call sendmoney in a loop and hit spurious out of funds errors
     // because we think that this newly generated transaction's change is
     // unavailable as we're not yet aware that it is in the mempool.
     //
     // Irrespective of the failure reason, un-marking fInMempool
     // out-of-order is incorrect - it should be unmarked when
     // TransactionRemovedFromMempool fires.
     bool ret = pwallet->chain().broadcastTransaction(
         GetConfig(), tx, err_string, pwallet->m_default_max_tx_fee, relay);
     fInMempool |= ret;
     return ret;
 }
 
 std::set<TxId> CWalletTx::GetConflicts() const {
     std::set<TxId> result;
     if (pwallet != nullptr) {
         const TxId &txid = GetId();
         result = pwallet->GetConflicts(txid);
         result.erase(txid);
     }
 
     return result;
 }
 
 Amount CWalletTx::GetCachableAmount(AmountType type, const isminefilter &filter,
                                     bool recalculate) const {
     auto &amount = m_amounts[type];
     if (recalculate || !amount.m_cached[filter]) {
         amount.Set(filter, type == DEBIT ? pwallet->GetDebit(*tx, filter)
                                          : pwallet->GetCredit(*tx, filter));
         m_is_cache_empty = false;
     }
     return amount.m_value[filter];
 }
 
 Amount CWalletTx::GetDebit(const isminefilter &filter) const {
     if (tx->vin.empty()) {
         return Amount::zero();
     }
 
     Amount debit = Amount::zero();
     if (filter & ISMINE_SPENDABLE) {
         debit += GetCachableAmount(DEBIT, ISMINE_SPENDABLE);
     }
     if (filter & ISMINE_WATCH_ONLY) {
         debit += GetCachableAmount(DEBIT, ISMINE_WATCH_ONLY);
     }
 
     return debit;
 }
 
 Amount CWalletTx::GetCredit(const isminefilter &filter) const {
     // Must wait until coinbase is safely deep enough in the chain before
     // valuing it.
     if (IsImmatureCoinBase()) {
         return Amount::zero();
     }
 
     Amount credit = Amount::zero();
     if (filter & ISMINE_SPENDABLE) {
         // GetBalance can assume transactions in mapWallet won't change.
         credit += GetCachableAmount(CREDIT, ISMINE_SPENDABLE);
     }
 
     if (filter & ISMINE_WATCH_ONLY) {
         credit += GetCachableAmount(CREDIT, ISMINE_WATCH_ONLY);
     }
 
     return credit;
 }
 
 Amount CWalletTx::GetImmatureCredit(bool fUseCache) const {
     if (IsImmatureCoinBase() && IsInMainChain()) {
         return GetCachableAmount(IMMATURE_CREDIT, ISMINE_SPENDABLE, !fUseCache);
     }
 
     return Amount::zero();
 }
 
 Amount CWalletTx::GetAvailableCredit(bool fUseCache,
                                      const isminefilter &filter) const {
     if (pwallet == nullptr) {
         return Amount::zero();
     }
 
     // Avoid caching ismine for NO or ALL cases (could remove this check and
     // simplify in the future).
     bool allow_cache =
         (filter & ISMINE_ALL) && (filter & ISMINE_ALL) != ISMINE_ALL;
 
     // Must wait until coinbase is safely deep enough in the chain before
     // valuing it.
     if (IsImmatureCoinBase()) {
         return Amount::zero();
     }
 
     if (fUseCache && allow_cache &&
         m_amounts[AVAILABLE_CREDIT].m_cached[filter]) {
         return m_amounts[AVAILABLE_CREDIT].m_value[filter];
     }
 
     bool allow_used_addresses =
         (filter & ISMINE_USED) ||
         !pwallet->IsWalletFlagSet(WALLET_FLAG_AVOID_REUSE);
     Amount nCredit = Amount::zero();
     const TxId &txid = GetId();
     for (uint32_t i = 0; i < tx->vout.size(); i++) {
         if (!pwallet->IsSpent(COutPoint(txid, i)) &&
             (allow_used_addresses || !pwallet->IsUsedDestination(txid, i))) {
             const CTxOut &txout = tx->vout[i];
             nCredit += pwallet->GetCredit(txout, filter);
             if (!MoneyRange(nCredit)) {
                 throw std::runtime_error(std::string(__func__) +
                                          " : value out of range");
             }
         }
     }
 
     if (allow_cache) {
         m_amounts[AVAILABLE_CREDIT].Set(filter, nCredit);
         m_is_cache_empty = false;
     }
 
     return nCredit;
 }
 
 Amount CWalletTx::GetImmatureWatchOnlyCredit(const bool fUseCache) const {
     if (IsImmatureCoinBase() && IsInMainChain()) {
         return GetCachableAmount(IMMATURE_CREDIT, ISMINE_WATCH_ONLY,
                                  !fUseCache);
     }
 
     return Amount::zero();
 }
 
 Amount CWalletTx::GetChange() const {
     if (fChangeCached) {
         return nChangeCached;
     }
 
     nChangeCached = pwallet->GetChange(*tx);
     fChangeCached = true;
     return nChangeCached;
 }
 
 bool CWalletTx::InMempool() const {
     return fInMempool;
 }
 
 bool CWalletTx::IsTrusted(interfaces::Chain::Lock &locked_chain) const {
     std::set<TxId> s;
     return IsTrusted(locked_chain, s);
 }
 
 bool CWalletTx::IsTrusted(interfaces::Chain::Lock &locked_chain,
                           std::set<TxId> &trusted_parents) const {
     // Quick answer in most cases
     TxValidationState state;
     if (!locked_chain.contextualCheckTransactionForCurrentBlock(
             this->pwallet->chainParams.GetConsensus(), *tx, state)) {
         return false;
     }
 
     int nDepth = GetDepthInMainChain();
     if (nDepth >= 1) {
         return true;
     }
 
     if (nDepth < 0) {
         return false;
     }
 
     // using wtx's cached debit
     if (!pwallet->m_spend_zero_conf_change || !IsFromMe(ISMINE_ALL)) {
         return false;
     }
 
     // Don't trust unconfirmed transactions from us unless they are in the
     // mempool.
     if (!InMempool()) {
         return false;
     }
 
     // Trusted if all inputs are from us and are in the mempool:
     for (const CTxIn &txin : tx->vin) {
         // Transactions not sent by us: not trusted
         const CWalletTx *parent = pwallet->GetWalletTx(txin.prevout.GetTxId());
         if (parent == nullptr) {
             return false;
         }
 
         const CTxOut &parentOut = parent->tx->vout[txin.prevout.GetN()];
         // Check that this specific input being spent is trusted
         if (pwallet->IsMine(parentOut) != ISMINE_SPENDABLE) {
             return false;
         }
         // If we've already trusted this parent, continue
         if (trusted_parents.count(parent->GetId())) {
             continue;
         }
         // Recurse to check that the parent is also trusted
         if (!parent->IsTrusted(locked_chain, trusted_parents)) {
             return false;
         }
         trusted_parents.insert(parent->GetId());
     }
 
     return true;
 }
 
 bool CWalletTx::IsEquivalentTo(const CWalletTx &_tx) const {
     CMutableTransaction tx1{*this->tx};
     CMutableTransaction tx2{*_tx.tx};
     for (auto &txin : tx1.vin) {
         txin.scriptSig = CScript();
     }
 
     for (auto &txin : tx2.vin) {
         txin.scriptSig = CScript();
     }
 
     return CTransaction(tx1) == CTransaction(tx2);
 }
 
 // Rebroadcast transactions from the wallet. We do this on a random timer
 // to slightly obfuscate which transactions come from our wallet.
 //
 // Ideally, we'd only resend transactions that we think should have been
 // mined in the most recent block. Any transaction that wasn't in the top
 // blockweight of transactions in the mempool shouldn't have been mined,
 // and so is probably just sitting in the mempool waiting to be confirmed.
 // Rebroadcasting does nothing to speed up confirmation and only damages
 // privacy.
 void CWallet::ResendWalletTransactions() {
     // During reindex, importing and IBD, old wallet transactions become
     // unconfirmed. Don't resend them as that would spam other nodes.
     if (!chain().isReadyToBroadcast()) {
         return;
     }
 
     // Do this infrequently and randomly to avoid giving away that these are our
     // transactions.
     if (GetTime() < nNextResend || !fBroadcastTransactions) {
         return;
     }
 
     bool fFirst = (nNextResend == 0);
     nNextResend = GetTime() + GetRand(30 * 60);
     if (fFirst) {
         return;
     }
 
     // Only do it if there's been a new block since last time
     if (m_best_block_time < nLastResend) {
         return;
     }
 
     nLastResend = GetTime();
 
     int submitted_tx_count = 0;
 
     { // locked_chain and cs_wallet scope
         auto locked_chain = chain().lock();
         LOCK(cs_wallet);
 
         // Relay transactions
         for (std::pair<const TxId, CWalletTx> &item : mapWallet) {
             CWalletTx &wtx = item.second;
             // Attempt to rebroadcast all txes more than 5 minutes older than
             // the last block. SubmitMemoryPoolAndRelay() will not rebroadcast
             // any confirmed or conflicting txs.
             if (wtx.nTimeReceived > m_best_block_time - 5 * 60) {
                 continue;
             }
             std::string unused_err_string;
             if (wtx.SubmitMemoryPoolAndRelay(unused_err_string, true)) {
                 ++submitted_tx_count;
             }
         }
     } // locked_chain and cs_wallet
 
     if (submitted_tx_count > 0) {
         WalletLogPrintf("%s: resubmit %u unconfirmed transactions\n", __func__,
                         submitted_tx_count);
     }
 }
 
 /** @} */ // end of mapWallet
 
 void MaybeResendWalletTxs() {
     for (const std::shared_ptr<CWallet> &pwallet : GetWallets()) {
         pwallet->ResendWalletTransactions();
     }
 }
 
 /**
  * @defgroup Actions
  *
  * @{
  */
 CWallet::Balance CWallet::GetBalance(const int min_depth,
                                      bool avoid_reuse) const {
     Balance ret;
     isminefilter reuse_filter = avoid_reuse ? ISMINE_NO : ISMINE_USED;
     auto locked_chain = chain().lock();
     LOCK(cs_wallet);
     std::set<TxId> trusted_parents;
     for (const auto &entry : mapWallet) {
         const CWalletTx &wtx = entry.second;
         const bool is_trusted{wtx.IsTrusted(*locked_chain, trusted_parents)};
         const int tx_depth{wtx.GetDepthInMainChain()};
         const Amount tx_credit_mine{wtx.GetAvailableCredit(
             /* fUseCache */ true, ISMINE_SPENDABLE | reuse_filter)};
         const Amount tx_credit_watchonly{wtx.GetAvailableCredit(
             /* fUseCache */ true, ISMINE_WATCH_ONLY | reuse_filter)};
         if (is_trusted && tx_depth >= min_depth) {
             ret.m_mine_trusted += tx_credit_mine;
             ret.m_watchonly_trusted += tx_credit_watchonly;
         }
         if (!is_trusted && tx_depth == 0 && wtx.InMempool()) {
             ret.m_mine_untrusted_pending += tx_credit_mine;
             ret.m_watchonly_untrusted_pending += tx_credit_watchonly;
         }
         ret.m_mine_immature += wtx.GetImmatureCredit();
         ret.m_watchonly_immature += wtx.GetImmatureWatchOnlyCredit();
     }
     return ret;
 }
 
 Amount CWallet::GetAvailableBalance(const CCoinControl *coinControl) const {
     auto locked_chain = chain().lock();
     LOCK(cs_wallet);
 
     Amount balance = Amount::zero();
     std::vector<COutput> vCoins;
     AvailableCoins(*locked_chain, vCoins, true, coinControl);
     for (const COutput &out : vCoins) {
         if (out.fSpendable) {
             balance += out.tx->tx->vout[out.i].nValue;
         }
     }
     return balance;
 }
 
 void CWallet::AvailableCoins(interfaces::Chain::Lock &locked_chain,
                              std::vector<COutput> &vCoins, bool fOnlySafe,
                              const CCoinControl *coinControl,
                              const Amount nMinimumAmount,
                              const Amount nMaximumAmount,
                              const Amount nMinimumSumAmount,
                              const uint64_t nMaximumCount) const {
     AssertLockHeld(cs_wallet);
 
     vCoins.clear();
     Amount nTotal = Amount::zero();
     // Either the WALLET_FLAG_AVOID_REUSE flag is not set (in which case we
     // always allow), or we default to avoiding, and only in the case where a
     // coin control object is provided, and has the avoid address reuse flag set
     // to false, do we allow already used addresses
     bool allow_used_addresses =
         !IsWalletFlagSet(WALLET_FLAG_AVOID_REUSE) ||
         (coinControl && !coinControl->m_avoid_address_reuse);
     const int min_depth = {coinControl ? coinControl->m_min_depth
                                        : DEFAULT_MIN_DEPTH};
     const int max_depth = {coinControl ? coinControl->m_max_depth
                                        : DEFAULT_MAX_DEPTH};
 
     const Consensus::Params params = this->chainParams.GetConsensus();
 
     std::set<TxId> trusted_parents;
     for (const auto &entry : mapWallet) {
         const TxId &wtxid = entry.first;
         const CWalletTx &wtx = entry.second;
 
         TxValidationState state;
         if (!locked_chain.contextualCheckTransactionForCurrentBlock(
                 params, *wtx.tx, state)) {
             continue;
         }
 
         if (wtx.IsImmatureCoinBase()) {
             continue;
         }
 
         int nDepth = wtx.GetDepthInMainChain();
         if (nDepth < 0) {
             continue;
         }
 
         // We should not consider coins which aren't at least in our mempool.
         // It's possible for these to be conflicted via ancestors which we may
         // never be able to detect.
         if (nDepth == 0 && !wtx.InMempool()) {
             continue;
         }
 
         bool safeTx = wtx.IsTrusted(locked_chain, trusted_parents);
 
         // Bitcoin-ABC: Removed check that prevents consideration of coins from
         // transactions that are replacing other transactions. This check based
         // on wtx.mapValue.count("replaces_txid") which was not being set
         // anywhere.
 
         // Similarly, we should not consider coins from transactions that have
         // been replaced. In the example above, we would want to prevent
         // creation of a transaction A' spending an output of A, because if
         // transaction B were initially confirmed, conflicting with A and A', we
         // wouldn't want to the user to create a transaction D intending to
         // replace A', but potentially resulting in a scenario where A, A', and
         // D could all be accepted (instead of just B and D, or just A and A'
         // like the user would want).
 
         // Bitcoin-ABC: retained this check as 'replaced_by_txid' is still set
         // in the wallet code.
         if (nDepth == 0 && wtx.mapValue.count("replaced_by_txid")) {
             safeTx = false;
         }
 
         if (fOnlySafe && !safeTx) {
             continue;
         }
 
         if (nDepth < min_depth || nDepth > max_depth) {
             continue;
         }
 
         for (uint32_t i = 0; i < wtx.tx->vout.size(); i++) {
             if (wtx.tx->vout[i].nValue < nMinimumAmount ||
                 wtx.tx->vout[i].nValue > nMaximumAmount) {
                 continue;
             }
 
             const COutPoint outpoint(wtxid, i);
 
             if (coinControl && coinControl->HasSelected() &&
                 !coinControl->fAllowOtherInputs &&
                 !coinControl->IsSelected(outpoint)) {
                 continue;
             }
 
             if (IsLockedCoin(outpoint)) {
                 continue;
             }
 
             if (IsSpent(outpoint)) {
                 continue;
             }
 
             isminetype mine = IsMine(wtx.tx->vout[i]);
 
             if (mine == ISMINE_NO) {
                 continue;
             }
 
             if (!allow_used_addresses && IsUsedDestination(wtxid, i)) {
                 continue;
             }
 
             std::unique_ptr<SigningProvider> provider =
                 GetSigningProvider(wtx.tx->vout[i].scriptPubKey);
 
             bool solvable =
                 provider ? IsSolvable(*provider, wtx.tx->vout[i].scriptPubKey)
                          : false;
             bool spendable =
                 ((mine & ISMINE_SPENDABLE) != ISMINE_NO) ||
                 (((mine & ISMINE_WATCH_ONLY) != ISMINE_NO) &&
                  (coinControl && coinControl->fAllowWatchOnly && solvable));
 
             vCoins.push_back(
                 COutput(&wtx, i, nDepth, spendable, solvable, safeTx,
                         (coinControl && coinControl->fAllowWatchOnly)));
 
             // Checks the sum amount of all UTXO's.
             if (nMinimumSumAmount != MAX_MONEY) {
                 nTotal += wtx.tx->vout[i].nValue;
 
                 if (nTotal >= nMinimumSumAmount) {
                     return;
                 }
             }
 
             // Checks the maximum number of UTXO's.
             if (nMaximumCount > 0 && vCoins.size() >= nMaximumCount) {
                 return;
             }
         }
     }
 }
 
 std::map<CTxDestination, std::vector<COutput>>
 CWallet::ListCoins(interfaces::Chain::Lock &locked_chain) const {
     AssertLockHeld(cs_wallet);
 
     std::map<CTxDestination, std::vector<COutput>> result;
     std::vector<COutput> availableCoins;
 
     AvailableCoins(locked_chain, availableCoins);
 
     for (const auto &coin : availableCoins) {
         CTxDestination address;
         if ((coin.fSpendable ||
              (IsWalletFlagSet(WALLET_FLAG_DISABLE_PRIVATE_KEYS) &&
               coin.fSolvable)) &&
             ExtractDestination(
                 FindNonChangeParentOutput(*coin.tx->tx, coin.i).scriptPubKey,
                 address)) {
             result[address].emplace_back(std::move(coin));
         }
     }
 
     std::vector<COutPoint> lockedCoins;
     ListLockedCoins(lockedCoins);
     // Include watch-only for LegacyScriptPubKeyMan wallets without private keys
     const bool include_watch_only =
         GetLegacyScriptPubKeyMan() &&
         IsWalletFlagSet(WALLET_FLAG_DISABLE_PRIVATE_KEYS);
     const isminetype is_mine_filter =
         include_watch_only ? ISMINE_WATCH_ONLY : ISMINE_SPENDABLE;
     for (const auto &output : lockedCoins) {
         auto it = mapWallet.find(output.GetTxId());
         if (it != mapWallet.end()) {
             int depth = it->second.GetDepthInMainChain();
             if (depth >= 0 && output.GetN() < it->second.tx->vout.size() &&
                 IsMine(it->second.tx->vout[output.GetN()]) == is_mine_filter) {
                 CTxDestination address;
                 if (ExtractDestination(
                         FindNonChangeParentOutput(*it->second.tx, output.GetN())
                             .scriptPubKey,
                         address)) {
                     result[address].emplace_back(
                         &it->second, output.GetN(), depth, true /* spendable */,
                         true /* solvable */, false /* safe */);
                 }
             }
         }
     }
 
     return result;
 }
 
 const CTxOut &CWallet::FindNonChangeParentOutput(const CTransaction &tx,
                                                  int output) const {
     const CTransaction *ptx = &tx;
     int n = output;
     while (IsChange(ptx->vout[n]) && ptx->vin.size() > 0) {
         const COutPoint &prevout = ptx->vin[0].prevout;
         auto it = mapWallet.find(prevout.GetTxId());
         if (it == mapWallet.end() ||
             it->second.tx->vout.size() <= prevout.GetN() ||
             !IsMine(it->second.tx->vout[prevout.GetN()])) {
             break;
         }
         ptx = it->second.tx.get();
         n = prevout.GetN();
     }
     return ptx->vout[n];
 }
 
 bool CWallet::SelectCoinsMinConf(
     const Amount nTargetValue, const CoinEligibilityFilter &eligibility_filter,
     std::vector<OutputGroup> groups, std::set<CInputCoin> &setCoinsRet,
     Amount &nValueRet, const CoinSelectionParams &coin_selection_params,
     bool &bnb_used) const {
     setCoinsRet.clear();
     nValueRet = Amount::zero();
 
     std::vector<OutputGroup> utxo_pool;
     if (coin_selection_params.use_bnb) {
         // Get long term estimate
         CCoinControl temp;
         temp.m_confirm_target = 1008;
         CFeeRate long_term_feerate = GetMinimumFeeRate(*this, temp);
 
         // Calculate cost of change
         Amount cost_of_change = chain().relayDustFee().GetFee(
                                     coin_selection_params.change_spend_size) +
                                 coin_selection_params.effective_fee.GetFee(
                                     coin_selection_params.change_output_size);
 
         // Filter by the min conf specs and add to utxo_pool and calculate
         // effective value
         for (OutputGroup &group : groups) {
             if (!group.EligibleForSpending(eligibility_filter)) {
                 continue;
             }
 
             group.fee = Amount::zero();
             group.long_term_fee = Amount::zero();
             group.effective_value = Amount::zero();
             for (auto it = group.m_outputs.begin();
                  it != group.m_outputs.end();) {
                 const CInputCoin &coin = *it;
                 Amount effective_value =
                     coin.txout.nValue -
                     (coin.m_input_bytes < 0
                          ? Amount::zero()
                          : coin_selection_params.effective_fee.GetFee(
                                coin.m_input_bytes));
                 // Only include outputs that are positive effective value (i.e.
                 // not dust)
                 if (effective_value > Amount::zero()) {
                     group.fee +=
                         coin.m_input_bytes < 0
                             ? Amount::zero()
                             : coin_selection_params.effective_fee.GetFee(
                                   coin.m_input_bytes);
                     group.long_term_fee +=
                         coin.m_input_bytes < 0
                             ? Amount::zero()
                             : long_term_feerate.GetFee(coin.m_input_bytes);
                     group.effective_value += effective_value;
                     ++it;
                 } else {
                     it = group.Discard(coin);
                 }
             }
             if (group.effective_value > Amount::zero()) {
                 utxo_pool.push_back(group);
             }
         }
         // Calculate the fees for things that aren't inputs
         Amount not_input_fees = coin_selection_params.effective_fee.GetFee(
             coin_selection_params.tx_noinputs_size);
         bnb_used = true;
         return SelectCoinsBnB(utxo_pool, nTargetValue, cost_of_change,
                               setCoinsRet, nValueRet, not_input_fees);
     } else {
         // Filter by the min conf specs and add to utxo_pool
         for (const OutputGroup &group : groups) {
             if (!group.EligibleForSpending(eligibility_filter)) {
                 continue;
             }
             utxo_pool.push_back(group);
         }
         bnb_used = false;
         return KnapsackSolver(nTargetValue, utxo_pool, setCoinsRet, nValueRet);
     }
 }
 
 bool CWallet::SelectCoins(const std::vector<COutput> &vAvailableCoins,
                           const Amount nTargetValue,
                           std::set<CInputCoin> &setCoinsRet, Amount &nValueRet,
                           const CCoinControl &coin_control,
                           CoinSelectionParams &coin_selection_params,
                           bool &bnb_used) const {
     std::vector<COutput> vCoins(vAvailableCoins);
 
     // coin control -> return all selected outputs (we want all selected to go
     // into the transaction for sure)
     if (coin_control.HasSelected() && !coin_control.fAllowOtherInputs) {
         // We didn't use BnB here, so set it to false.
         bnb_used = false;
 
         for (const COutput &out : vCoins) {
             if (!out.fSpendable) {
                 continue;
             }
 
             nValueRet += out.tx->tx->vout[out.i].nValue;
             setCoinsRet.insert(out.GetInputCoin());
         }
 
         return (nValueRet >= nTargetValue);
     }
 
     // Calculate value from preset inputs and store them.
     std::set<CInputCoin> setPresetCoins;
     Amount nValueFromPresetInputs = Amount::zero();
 
     std::vector<COutPoint> vPresetInputs;
     coin_control.ListSelected(vPresetInputs);
 
     for (const COutPoint &outpoint : vPresetInputs) {
         // For now, don't use BnB if preset inputs are selected. TODO: Enable
         // this later
         bnb_used = false;
         coin_selection_params.use_bnb = false;
 
         std::map<TxId, CWalletTx>::const_iterator it =
             mapWallet.find(outpoint.GetTxId());
         if (it == mapWallet.end()) {
             // TODO: Allow non-wallet inputs
             return false;
         }
 
         const CWalletTx &wtx = it->second;
         // Clearly invalid input, fail.
         if (wtx.tx->vout.size() <= outpoint.GetN()) {
             return false;
         }
 
         // Just to calculate the marginal byte size
         nValueFromPresetInputs += wtx.tx->vout[outpoint.GetN()].nValue;
         setPresetCoins.insert(CInputCoin(wtx.tx, outpoint.GetN()));
     }
 
     // Remove preset inputs from vCoins
     for (std::vector<COutput>::iterator it = vCoins.begin();
          it != vCoins.end() && coin_control.HasSelected();) {
         if (setPresetCoins.count(it->GetInputCoin())) {
             it = vCoins.erase(it);
         } else {
             ++it;
         }
     }
 
     size_t max_ancestors{0};
     size_t max_descendants{0};
     chain().getPackageLimits(max_ancestors, max_descendants);
     bool fRejectLongChains = gArgs.GetBoolArg(
         "-walletrejectlongchains", DEFAULT_WALLET_REJECT_LONG_CHAINS);
 
     // form groups from remaining coins; note that preset coins will not
     // automatically have their associated (same address) coins included
     if (coin_control.m_avoid_partial_spends &&
         vCoins.size() > OUTPUT_GROUP_MAX_ENTRIES) {
         // Cases where we have 11+ outputs all pointing to the same destination
         // may result in privacy leaks as they will potentially be
         // deterministically sorted. We solve that by explicitly shuffling the
         // outputs before processing
         Shuffle(vCoins.begin(), vCoins.end(), FastRandomContext());
     }
 
     std::vector<OutputGroup> groups = GroupOutputs(
         vCoins, !coin_control.m_avoid_partial_spends, max_ancestors);
 
     bool res =
         nTargetValue <= nValueFromPresetInputs ||
         SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs,
                            CoinEligibilityFilter(1, 6, 0), groups, setCoinsRet,
                            nValueRet, coin_selection_params, bnb_used) ||
         SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs,
                            CoinEligibilityFilter(1, 1, 0), groups, setCoinsRet,
                            nValueRet, coin_selection_params, bnb_used) ||
         (m_spend_zero_conf_change &&
          SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs,
                             CoinEligibilityFilter(0, 1, 2), groups, setCoinsRet,
                             nValueRet, coin_selection_params, bnb_used)) ||
         (m_spend_zero_conf_change &&
          SelectCoinsMinConf(
              nTargetValue - nValueFromPresetInputs,
              CoinEligibilityFilter(0, 1, std::min<size_t>(4, max_ancestors / 3),
                                    std::min<size_t>(4, max_descendants / 3)),
              groups, setCoinsRet, nValueRet, coin_selection_params,
              bnb_used)) ||
         (m_spend_zero_conf_change &&
          SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs,
                             CoinEligibilityFilter(0, 1, max_ancestors / 2,
                                                   max_descendants / 2),
                             groups, setCoinsRet, nValueRet,
                             coin_selection_params, bnb_used)) ||
         (m_spend_zero_conf_change &&
          SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs,
                             CoinEligibilityFilter(0, 1, max_ancestors - 1,
                                                   max_descendants - 1),
                             groups, setCoinsRet, nValueRet,
                             coin_selection_params, bnb_used)) ||
         (m_spend_zero_conf_change && !fRejectLongChains &&
          SelectCoinsMinConf(
              nTargetValue - nValueFromPresetInputs,
              CoinEligibilityFilter(0, 1, std::numeric_limits<uint64_t>::max()),
              groups, setCoinsRet, nValueRet, coin_selection_params, bnb_used));
 
     // Because SelectCoinsMinConf clears the setCoinsRet, we now add the
     // possible inputs to the coinset.
     util::insert(setCoinsRet, setPresetCoins);
 
     // Add preset inputs to the total value selected.
     nValueRet += nValueFromPresetInputs;
 
     return res;
 }
 
 bool CWallet::SignTransaction(CMutableTransaction &tx) {
     AssertLockHeld(cs_wallet);
     // sign the new tx
     int nIn = 0;
     for (CTxIn &input : tx.vin) {
         auto mi = mapWallet.find(input.prevout.GetTxId());
         if (mi == mapWallet.end() ||
             input.prevout.GetN() >= mi->second.tx->vout.size()) {
             return false;
         }
         const CScript &scriptPubKey =
             mi->second.tx->vout[input.prevout.GetN()].scriptPubKey;
         const Amount amount = mi->second.tx->vout[input.prevout.GetN()].nValue;
         SignatureData sigdata;
         SigHashType sigHashType = SigHashType().withForkId();
 
         std::unique_ptr<SigningProvider> provider =
             GetSigningProvider(scriptPubKey);
         if (!provider) {
             // We don't know about this scriptpbuKey;
             return false;
         }
 
         if (!ProduceSignature(*provider,
                               MutableTransactionSignatureCreator(
                                   &tx, nIn, amount, sigHashType),
                               scriptPubKey, sigdata)) {
             return false;
         }
         UpdateInput(input, sigdata);
         nIn++;
     }
     return true;
 }
 
 bool CWallet::FundTransaction(CMutableTransaction &tx, Amount &nFeeRet,
                               int &nChangePosInOut, bilingual_str &error,
                               bool lockUnspents,
                               const std::set<int> &setSubtractFeeFromOutputs,
                               CCoinControl coinControl) {
     std::vector<CRecipient> vecSend;
 
     // Turn the txout set into a CRecipient vector.
     for (size_t idx = 0; idx < tx.vout.size(); idx++) {
         const CTxOut &txOut = tx.vout[idx];
         CRecipient recipient = {txOut.scriptPubKey, txOut.nValue,
                                 setSubtractFeeFromOutputs.count(idx) == 1};
         vecSend.push_back(recipient);
     }
 
     coinControl.fAllowOtherInputs = true;
 
     for (const CTxIn &txin : tx.vin) {
         coinControl.Select(txin.prevout);
     }
 
     // Acquire the locks to prevent races to the new locked unspents between the
     // CreateTransaction call and LockCoin calls (when lockUnspents is true).
     auto locked_chain = chain().lock();
     LOCK(cs_wallet);
 
     CTransactionRef tx_new;
     if (!CreateTransaction(*locked_chain, vecSend, tx_new, nFeeRet,
                            nChangePosInOut, error, coinControl, false)) {
         return false;
     }
 
     if (nChangePosInOut != -1) {
         tx.vout.insert(tx.vout.begin() + nChangePosInOut,
                        tx_new->vout[nChangePosInOut]);
     }
 
     // Copy output sizes from new transaction; they may have had the fee
     // subtracted from them.
     for (size_t idx = 0; idx < tx.vout.size(); idx++) {
         tx.vout[idx].nValue = tx_new->vout[idx].nValue;
     }
 
     // Add new txins (keeping original txin scriptSig/order)
     for (const CTxIn &txin : tx_new->vin) {
         if (!coinControl.IsSelected(txin.prevout)) {
             tx.vin.push_back(txin);
 
             if (lockUnspents) {
                 LockCoin(txin.prevout);
             }
         }
     }
 
     return true;
 }
 
 static bool IsCurrentForAntiFeeSniping(interfaces::Chain &chain,
                                        interfaces::Chain::Lock &locked_chain) {
     if (chain.isInitialBlockDownload()) {
         return false;
     }
 
     // in seconds
     constexpr int64_t MAX_ANTI_FEE_SNIPING_TIP_AGE = 8 * 60 * 60;
     if (locked_chain.getBlockTime(*locked_chain.getHeight()) <
         (GetTime() - MAX_ANTI_FEE_SNIPING_TIP_AGE)) {
         return false;
     }
     return true;
 }
 
 /**
  * Return a height-based locktime for new transactions (uses the height of the
  * current chain tip unless we are not synced with the current chain
  */
 static uint32_t
 GetLocktimeForNewTransaction(interfaces::Chain &chain,
                              interfaces::Chain::Lock &locked_chain) {
     uint32_t const height = locked_chain.getHeight().value_or(-1);
     uint32_t locktime;
     // Discourage fee sniping.
     //
     // For a large miner the value of the transactions in the best block and
     // the mempool can exceed the cost of deliberately attempting to mine two
     // blocks to orphan the current best block. By setting nLockTime such that
     // only the next block can include the transaction, we discourage this
     // practice as the height restricted and limited blocksize gives miners
     // considering fee sniping fewer options for pulling off this attack.
     //
     // A simple way to think about this is from the wallet's point of view we
     // always want the blockchain to move forward. By setting nLockTime this
     // way we're basically making the statement that we only want this
     // transaction to appear in the next block; we don't want to potentially
     // encourage reorgs by allowing transactions to appear at lower heights
     // than the next block in forks of the best chain.
     //
     // Of course, the subsidy is high enough, and transaction volume low
     // enough, that fee sniping isn't a problem yet, but by implementing a fix
     // now we ensure code won't be written that makes assumptions about
     // nLockTime that preclude a fix later.
     if (IsCurrentForAntiFeeSniping(chain, locked_chain)) {
         locktime = height;
 
         // Secondly occasionally randomly pick a nLockTime even further back, so
         // that transactions that are delayed after signing for whatever reason,
         // e.g. high-latency mix networks and some CoinJoin implementations,
         // have better privacy.
         if (GetRandInt(10) == 0) {
             locktime = std::max(0, int(locktime) - GetRandInt(100));
         }
     } else {
         // If our chain is lagging behind, we can't discourage fee sniping nor
         // help the privacy of high-latency transactions. To avoid leaking a
         // potentially unique "nLockTime fingerprint", set nLockTime to a
         // constant.
         locktime = 0;
     }
     assert(locktime <= height);
     assert(locktime < LOCKTIME_THRESHOLD);
     return locktime;
 }
 
 OutputType
 CWallet::TransactionChangeType(OutputType change_type,
                                const std::vector<CRecipient> &vecSend) {
     // If -changetype is specified, always use that change type.
     if (change_type != OutputType::CHANGE_AUTO) {
         return change_type;
     }
 
     // if m_default_address_type is legacy, use legacy address as change.
     if (m_default_address_type == OutputType::LEGACY) {
         return OutputType::LEGACY;
     }
 
     // else use m_default_address_type for change
     return m_default_address_type;
 }
 
 bool CWallet::CreateTransactionInternal(interfaces::Chain::Lock &locked_chainIn,
                                         const std::vector<CRecipient> &vecSend,
                                         CTransactionRef &tx, Amount &nFeeRet,
                                         int &nChangePosInOut,
                                         bilingual_str &error,
                                         const CCoinControl &coin_control,
                                         bool sign) {
     Amount nValue = Amount::zero();
     const OutputType change_type = TransactionChangeType(
         coin_control.m_change_type ? *coin_control.m_change_type
                                    : m_default_change_type,
         vecSend);
     ReserveDestination reservedest(this, change_type);
     int nChangePosRequest = nChangePosInOut;
     unsigned int nSubtractFeeFromAmount = 0;
     for (const auto &recipient : vecSend) {
         if (nValue < Amount::zero() || recipient.nAmount < Amount::zero()) {
             error = _("Transaction amounts must not be negative");
             return false;
         }
 
         nValue += recipient.nAmount;
 
         if (recipient.fSubtractFeeFromAmount) {
             nSubtractFeeFromAmount++;
         }
     }
 
     if (vecSend.empty()) {
         error = _("Transaction must have at least one recipient");
         return false;
     }
 
     CMutableTransaction txNew;
 
     txNew.nLockTime = GetLocktimeForNewTransaction(chain(), locked_chainIn);
 
     {
         std::set<CInputCoin> setCoins;
         auto locked_chain = chain().lock();
         LOCK(cs_wallet);
 
         std::vector<COutput> vAvailableCoins;
         AvailableCoins(*locked_chain, vAvailableCoins, true, &coin_control);
         // Parameters for coin selection, init with dummy
         CoinSelectionParams coin_selection_params;
 
         // Create change script that will be used if we need change
         // TODO: pass in scriptChange instead of reservedest so
         // change transaction isn't always pay-to-bitcoin-address
         CScript scriptChange;
 
         // coin control: send change to custom address
         if (!boost::get<CNoDestination>(&coin_control.destChange)) {
             scriptChange = GetScriptForDestination(coin_control.destChange);
 
             // no coin control: send change to newly generated address
         } else {
             // Note: We use a new key here to keep it from being obvious
             // which side is the change.
             //  The drawback is that by not reusing a previous key, the
             //  change may be lost if a backup is restored, if the backup
             //  doesn't have the new private key for the change. If we
             //  reused the old key, it would be possible to add code to look
             //  for and rediscover unknown transactions that were written
             //  with keys of ours to recover post-backup change.
 
             // Reserve a new key pair from key pool
             if (!CanGetAddresses(true)) {
                 error = _("Can't generate a change-address key. No keys in the "
                           "internal keypool and can't generate any keys.");
                 return false;
             }
             CTxDestination dest;
             bool ret = reservedest.GetReservedDestination(dest, true);
             if (!ret) {
                 error = _("Keypool ran out, please call keypoolrefill first");
                 return false;
             }
 
             scriptChange = GetScriptForDestination(dest);
         }
         CTxOut change_prototype_txout(Amount::zero(), scriptChange);
         coin_selection_params.change_output_size =
             GetSerializeSize(change_prototype_txout);
 
         // Get the fee rate to use effective values in coin selection
         CFeeRate nFeeRateNeeded = GetMinimumFeeRate(*this, coin_control);
 
         nFeeRet = Amount::zero();
         bool pick_new_inputs = true;
         Amount nValueIn = Amount::zero();
 
         // BnB selector is the only selector used when this is true.
         // That should only happen on the first pass through the loop.
         // If we are doing subtract fee from recipient, then don't use BnB
         coin_selection_params.use_bnb = nSubtractFeeFromAmount == 0;
         // Start with no fee and loop until there is enough fee
         while (true) {
             nChangePosInOut = nChangePosRequest;
             txNew.vin.clear();
             txNew.vout.clear();
             bool fFirst = true;
 
             Amount nValueToSelect = nValue;
             if (nSubtractFeeFromAmount == 0) {
                 nValueToSelect += nFeeRet;
             }
 
             // Static size overhead + outputs vsize. 4 nVersion, 4 nLocktime, 1
             // input count, 1 output count
             coin_selection_params.tx_noinputs_size = 10;
             // vouts to the payees
             for (const auto &recipient : vecSend) {
                 CTxOut txout(recipient.nAmount, recipient.scriptPubKey);
 
                 if (recipient.fSubtractFeeFromAmount) {
                     assert(nSubtractFeeFromAmount != 0);
                     // Subtract fee equally from each selected recipient.
                     txout.nValue -= nFeeRet / int(nSubtractFeeFromAmount);
 
                     // First receiver pays the remainder not divisible by output
                     // count.
                     if (fFirst) {
                         fFirst = false;
                         txout.nValue -= nFeeRet % int(nSubtractFeeFromAmount);
                     }
                 }
 
                 // Include the fee cost for outputs. Note this is only used for
                 // BnB right now
                 coin_selection_params.tx_noinputs_size +=
                     ::GetSerializeSize(txout, PROTOCOL_VERSION);
 
                 if (IsDust(txout, chain().relayDustFee())) {
                     if (recipient.fSubtractFeeFromAmount &&
                         nFeeRet > Amount::zero()) {
                         if (txout.nValue < Amount::zero()) {
                             error = _("The transaction amount is too small to "
                                       "pay the fee");
                         } else {
                             error = _("The transaction amount is too small to "
                                       "send after the fee has been deducted");
                         }
                     } else {
                         error = _("Transaction amount too small");
                     }
 
                     return false;
                 }
 
                 txNew.vout.push_back(txout);
             }
 
             // Choose coins to use
             bool bnb_used;
             if (pick_new_inputs) {
                 nValueIn = Amount::zero();
                 setCoins.clear();
                 coin_selection_params.change_spend_size =
                     CalculateMaximumSignedInputSize(change_prototype_txout,
                                                     this);
                 coin_selection_params.effective_fee = nFeeRateNeeded;
                 if (!SelectCoins(vAvailableCoins, nValueToSelect, setCoins,
                                  nValueIn, coin_control, coin_selection_params,
                                  bnb_used)) {
                     // If BnB was used, it was the first pass. No longer the
                     // first pass and continue loop with knapsack.
                     if (bnb_used) {
                         coin_selection_params.use_bnb = false;
                         continue;
                     } else {
                         error = _("Insufficient funds");
                         return false;
                     }
                 }
             } else {
                 bnb_used = false;
             }
 
             const Amount nChange = nValueIn - nValueToSelect;
             if (nChange > Amount::zero()) {
                 // Fill a vout to ourself.
                 CTxOut newTxOut(nChange, scriptChange);
 
                 // Never create dust outputs; if we would, just add the dust to
                 // the fee.
                 // The nChange when BnB is used is always going to go to fees.
                 if (IsDust(newTxOut, chain().relayDustFee()) || bnb_used) {
                     nChangePosInOut = -1;
                     nFeeRet += nChange;
                 } else {
                     if (nChangePosInOut == -1) {
                         // Insert change txn at random position:
                         nChangePosInOut = GetRandInt(txNew.vout.size() + 1);
                     } else if ((unsigned int)nChangePosInOut >
                                txNew.vout.size()) {
                         error = _("Change index out of range");
                         return false;
                     }
 
                     std::vector<CTxOut>::iterator position =
                         txNew.vout.begin() + nChangePosInOut;
                     txNew.vout.insert(position, newTxOut);
                 }
             } else {
                 nChangePosInOut = -1;
             }
 
             // Dummy fill vin for maximum size estimation
             //
             for (const auto &coin : setCoins) {
                 txNew.vin.push_back(CTxIn(coin.outpoint, CScript()));
             }
 
             CTransaction txNewConst(txNew);
             int nBytes = CalculateMaximumSignedTxSize(
                 txNewConst, this, coin_control.fAllowWatchOnly);
             if (nBytes < 0) {
                 error = _("Signing transaction failed");
                 return false;
             }
 
             Amount nFeeNeeded = GetMinimumFee(*this, nBytes, coin_control);
 
             if (nFeeRet >= nFeeNeeded) {
                 // Reduce fee to only the needed amount if possible. This
                 // prevents potential overpayment in fees if the coins selected
                 // to meet nFeeNeeded result in a transaction that requires less
                 // fee than the prior iteration.
 
                 // If we have no change and a big enough excess fee, then try to
                 // construct transaction again only without picking new inputs.
                 // We now know we only need the smaller fee (because of reduced
                 // tx size) and so we should add a change output. Only try this
                 // once.
                 if (nChangePosInOut == -1 && nSubtractFeeFromAmount == 0 &&
                     pick_new_inputs) {
                     // Add 2 as a buffer in case increasing # of outputs changes
                     // compact size
                     unsigned int tx_size_with_change =
                         nBytes + coin_selection_params.change_output_size + 2;
                     Amount fee_needed_with_change =
                         GetMinimumFee(*this, tx_size_with_change, coin_control);
                     Amount minimum_value_for_change = GetDustThreshold(
                         change_prototype_txout, chain().relayDustFee());
                     if (nFeeRet >=
                         fee_needed_with_change + minimum_value_for_change) {
                         pick_new_inputs = false;
                         nFeeRet = fee_needed_with_change;
                         continue;
                     }
                 }
 
                 // If we have change output already, just increase it
                 if (nFeeRet > nFeeNeeded && nChangePosInOut != -1 &&
                     nSubtractFeeFromAmount == 0) {
                     Amount extraFeePaid = nFeeRet - nFeeNeeded;
                     std::vector<CTxOut>::iterator change_position =
                         txNew.vout.begin() + nChangePosInOut;
                     change_position->nValue += extraFeePaid;
                     nFeeRet -= extraFeePaid;
                 }
 
                 // Done, enough fee included.
                 break;
             } else if (!pick_new_inputs) {
                 // This shouldn't happen, we should have had enough excess fee
                 // to pay for the new output and still meet nFeeNeeded.
                 // Or we should have just subtracted fee from recipients and
                 // nFeeNeeded should not have changed.
                 error = _("Transaction fee and change calculation failed");
                 return false;
             }
 
             // Try to reduce change to include necessary fee.
             if (nChangePosInOut != -1 && nSubtractFeeFromAmount == 0) {
                 Amount additionalFeeNeeded = nFeeNeeded - nFeeRet;
                 std::vector<CTxOut>::iterator change_position =
                     txNew.vout.begin() + nChangePosInOut;
                 // Only reduce change if remaining amount is still a large
                 // enough output.
                 if (change_position->nValue >=
                     MIN_FINAL_CHANGE + additionalFeeNeeded) {
                     change_position->nValue -= additionalFeeNeeded;
                     nFeeRet += additionalFeeNeeded;
                     // Done, able to increase fee from change.
                     break;
                 }
             }
 
             // If subtracting fee from recipients, we now know what fee we
             // need to subtract, we have no reason to reselect inputs.
             if (nSubtractFeeFromAmount > 0) {
                 pick_new_inputs = false;
             }
 
             // Include more fee and try again.
             nFeeRet = nFeeNeeded;
             coin_selection_params.use_bnb = false;
             continue;
         }
 
         // Shuffle selected coins and fill in final vin
         txNew.vin.clear();
         std::vector<CInputCoin> selected_coins(setCoins.begin(),
                                                setCoins.end());
         Shuffle(selected_coins.begin(), selected_coins.end(),
                 FastRandomContext());
 
         // Note how the sequence number is set to non-maxint so that
         // the nLockTime set above actually works.
         for (const auto &coin : selected_coins) {
             txNew.vin.push_back(
                 CTxIn(coin.outpoint, CScript(),
                       std::numeric_limits<uint32_t>::max() - 1));
         }
 
         if (sign) {
             SigHashType sigHashType = SigHashType().withForkId();
 
             int nIn = 0;
             for (const auto &coin : selected_coins) {
                 const CScript &scriptPubKey = coin.txout.scriptPubKey;
                 SignatureData sigdata;
 
                 std::unique_ptr<SigningProvider> provider =
                     GetSigningProvider(scriptPubKey);
                 if (!provider ||
                     !ProduceSignature(
                         *provider,
                         MutableTransactionSignatureCreator(
                             &txNew, nIn, coin.txout.nValue, sigHashType),
                         scriptPubKey, sigdata)) {
                     error = _("Signing transaction failed");
                     return false;
                 }
 
                 UpdateInput(txNew.vin.at(nIn), sigdata);
                 nIn++;
             }
         }
 
         // Return the constructed transaction data.
         tx = MakeTransactionRef(std::move(txNew));
 
         // Limit size.
         if (tx->GetTotalSize() > MAX_STANDARD_TX_SIZE) {
             error = _("Transaction too large");
             return false;
         }
     }
 
     if (nFeeRet > m_default_max_tx_fee) {
         error = Untranslated(
             TransactionErrorString(TransactionError::MAX_FEE_EXCEEDED));
         return false;
     }
 
     if (gArgs.GetBoolArg("-walletrejectlongchains",
                          DEFAULT_WALLET_REJECT_LONG_CHAINS)) {
         // Lastly, ensure this tx will pass the mempool's chain limits
         if (!chain().checkChainLimits(tx)) {
             error = _("Transaction has too long of a mempool chain");
             return false;
         }
     }
 
     // Before we return success, we assume any change key will be used to
     // prevent accidental re-use.
     reservedest.KeepDestination();
 
     return true;
 }
 
 bool CWallet::CreateTransaction(interfaces::Chain::Lock &locked_chain,
                                 const std::vector<CRecipient> &vecSend,
                                 CTransactionRef &tx, Amount &nFeeRet,
                                 int &nChangePosInOut, bilingual_str &error,
                                 const CCoinControl &coin_control, bool sign) {
     int nChangePosIn = nChangePosInOut;
     CTransactionRef tx2 = tx;
     bool res =
         CreateTransactionInternal(locked_chain, vecSend, tx, nFeeRet,
                                   nChangePosInOut, error, coin_control, sign);
     // try with avoidpartialspends unless it's enabled already
     if (res &&
         nFeeRet >
             Amount::zero() /* 0 means non-functional fee rate estimation */
         && m_max_aps_fee > (-1 * SATOSHI) &&
         !coin_control.m_avoid_partial_spends) {
         CCoinControl tmp_cc = coin_control;
         tmp_cc.m_avoid_partial_spends = true;
         Amount nFeeRet2;
         int nChangePosInOut2 = nChangePosIn;
         // fired and forgotten; if an error occurs, we discard the results
         bilingual_str error2;
         if (CreateTransactionInternal(locked_chain, vecSend, tx2, nFeeRet2,
                                       nChangePosInOut2, error2, tmp_cc, sign)) {
             // if fee of this alternative one is within the range of the max
             // fee, we use this one
             const bool use_aps = nFeeRet2 <= nFeeRet + m_max_aps_fee;
             WalletLogPrintf(
                 "Fee non-grouped = %lld, grouped = %lld, using %s\n", nFeeRet,
                 nFeeRet2, use_aps ? "grouped" : "non-grouped");
             if (use_aps) {
                 tx = tx2;
                 nFeeRet = nFeeRet2;
                 nChangePosInOut = nChangePosInOut2;
             }
         }
     }
     return res;
 }
 
 void CWallet::CommitTransaction(
     CTransactionRef tx, mapValue_t mapValue,
     std::vector<std::pair<std::string, std::string>> orderForm) {
     auto locked_chain = chain().lock();
     LOCK(cs_wallet);
 
     CWalletTx wtxNew(this, std::move(tx));
     wtxNew.mapValue = std::move(mapValue);
     wtxNew.vOrderForm = std::move(orderForm);
     wtxNew.fTimeReceivedIsTxTime = true;
     wtxNew.fFromMe = true;
 
     WalletLogPrintfToBeContinued("CommitTransaction:\n%s",
                                  wtxNew.tx->ToString());
 
     // Add tx to wallet, because if it has change it's also ours, otherwise just
     // for transaction history.
     AddToWallet(wtxNew);
 
     // Notify that old coins are spent.
     for (const CTxIn &txin : wtxNew.tx->vin) {
         CWalletTx &coin = mapWallet.at(txin.prevout.GetTxId());
         coin.BindWallet(this);
         NotifyTransactionChanged(this, coin.GetId(), CT_UPDATED);
     }
 
     // Get the inserted-CWalletTx from mapWallet so that the
     // fInMempool flag is cached properly
     CWalletTx &wtx = mapWallet.at(wtxNew.GetId());
 
     if (!fBroadcastTransactions) {
         // Don't submit tx to the mempool
         return;
     }
 
     std::string err_string;
     if (!wtx.SubmitMemoryPoolAndRelay(err_string, true)) {
         WalletLogPrintf("CommitTransaction(): Transaction cannot be broadcast "
                         "immediately, %s\n",
                         err_string);
         // TODO: if we expect the failure to be long term or permanent, instead
         // delete wtx from the wallet and return failure.
     }
 }
 
 DBErrors CWallet::LoadWallet(bool &fFirstRunRet) {
     // Even if we don't use this lock in this function, we want to preserve
     // lock order in LoadToWallet if query of chain state is needed to know
     // tx status. If lock can't be taken (e.g bitcoin-wallet), tx confirmation
     // status may be not reliable.
     auto locked_chain = LockChain();
     LOCK(cs_wallet);
 
     fFirstRunRet = false;
     DBErrors nLoadWalletRet = WalletBatch(*database, "cr+").LoadWallet(this);
     if (nLoadWalletRet == DBErrors::NEED_REWRITE) {
         if (database->Rewrite("\x04pool")) {
             for (const auto &spk_man_pair : m_spk_managers) {
                 spk_man_pair.second->RewriteDB();
             }
         }
     }
 
     // This wallet is in its first run if there are no ScriptPubKeyMans and it
     // isn't blank or no privkeys
     fFirstRunRet = m_spk_managers.empty() &&
                    !IsWalletFlagSet(WALLET_FLAG_DISABLE_PRIVATE_KEYS) &&
                    !IsWalletFlagSet(WALLET_FLAG_BLANK_WALLET);
     if (fFirstRunRet) {
         assert(m_external_spk_managers.empty());
         assert(m_internal_spk_managers.empty());
     }
 
     if (nLoadWalletRet != DBErrors::LOAD_OK) {
         return nLoadWalletRet;
     }
 
     return DBErrors::LOAD_OK;
 }
 
 DBErrors CWallet::ZapSelectTx(std::vector<TxId> &txIdsIn,
                               std::vector<TxId> &txIdsOut) {
     AssertLockHeld(cs_wallet);
     DBErrors nZapSelectTxRet =
         WalletBatch(*database, "cr+").ZapSelectTx(txIdsIn, txIdsOut);
     for (const TxId &txid : txIdsOut) {
         const auto &it = mapWallet.find(txid);
         wtxOrdered.erase(it->second.m_it_wtxOrdered);
         mapWallet.erase(it);
         NotifyTransactionChanged(this, txid, CT_DELETED);
     }
 
     if (nZapSelectTxRet == DBErrors::NEED_REWRITE) {
         if (database->Rewrite("\x04pool")) {
             for (const auto &spk_man_pair : m_spk_managers) {
                 spk_man_pair.second->RewriteDB();
             }
         }
     }
 
     if (nZapSelectTxRet != DBErrors::LOAD_OK) {
         return nZapSelectTxRet;
     }
 
     MarkDirty();
 
     return DBErrors::LOAD_OK;
 }
 
 DBErrors CWallet::ZapWalletTx(std::vector<CWalletTx> &vWtx) {
     DBErrors nZapWalletTxRet = WalletBatch(*database, "cr+").ZapWalletTx(vWtx);
     if (nZapWalletTxRet == DBErrors::NEED_REWRITE) {
         if (database->Rewrite("\x04pool")) {
             for (const auto &spk_man_pair : m_spk_managers) {
                 spk_man_pair.second->RewriteDB();
             }
         }
     }
 
     if (nZapWalletTxRet != DBErrors::LOAD_OK) {
         return nZapWalletTxRet;
     }
 
     return DBErrors::LOAD_OK;
 }
 
 bool CWallet::SetAddressBookWithDB(WalletBatch &batch,
                                    const CTxDestination &address,
                                    const std::string &strName,
                                    const std::string &strPurpose) {
     bool fUpdated = false;
     {
         LOCK(cs_wallet);
         std::map<CTxDestination, CAddressBookData>::iterator mi =
             m_address_book.find(address);
         fUpdated = (mi != m_address_book.end() && !mi->second.IsChange());
         m_address_book[address].SetLabel(strName);
         // Update purpose only if requested.
         if (!strPurpose.empty()) {
             m_address_book[address].purpose = strPurpose;
         }
     }
 
     NotifyAddressBookChanged(this, address, strName,
                              IsMine(address) != ISMINE_NO, strPurpose,
                              (fUpdated ? CT_UPDATED : CT_NEW));
     if (!strPurpose.empty() && !batch.WritePurpose(address, strPurpose)) {
         return false;
     }
     return batch.WriteName(address, strName);
 }
 
 bool CWallet::SetAddressBook(const CTxDestination &address,
                              const std::string &strName,
                              const std::string &strPurpose) {
     WalletBatch batch(*database);
     return SetAddressBookWithDB(batch, address, strName, strPurpose);
 }
 
 bool CWallet::DelAddressBook(const CTxDestination &address) {
     // If we want to delete receiving addresses, we need to take care that
     // DestData "used" (and possibly newer DestData) gets preserved (and the
     // "deleted" address transformed into a change entry instead of actually
     // being deleted)
     // NOTE: This isn't a problem for sending addresses because they never have
     // any DestData yet! When adding new DestData, it should be considered here
     // whether to retain or delete it (or move it?).
     if (IsMine(address)) {
         WalletLogPrintf("%s called with IsMine address, NOT SUPPORTED. Please "
                         "report this bug! %s\n",
                         __func__, PACKAGE_BUGREPORT);
         return false;
     }
 
     {
         LOCK(cs_wallet);
 
         // Delete destdata tuples associated with address
         for (const std::pair<const std::string, std::string> &item :
              m_address_book[address].destdata) {
             WalletBatch(*database).EraseDestData(address, item.first);
         }
         m_address_book.erase(address);
     }
 
     NotifyAddressBookChanged(this, address, "", IsMine(address) != ISMINE_NO,
                              "", CT_DELETED);
 
     WalletBatch(*database).ErasePurpose(address);
     return WalletBatch(*database).EraseName(address);
 }
 
 size_t CWallet::KeypoolCountExternalKeys() {
     AssertLockHeld(cs_wallet);
 
     unsigned int count = 0;
     for (auto spk_man : GetActiveScriptPubKeyMans()) {
         count += spk_man->KeypoolCountExternalKeys();
     }
 
     return count;
 }
 
 unsigned int CWallet::GetKeyPoolSize() const {
     AssertLockHeld(cs_wallet);
 
     unsigned int count = 0;
     for (auto spk_man : GetActiveScriptPubKeyMans()) {
         count += spk_man->GetKeyPoolSize();
     }
     return count;
 }
 
 bool CWallet::TopUpKeyPool(unsigned int kpSize) {
     LOCK(cs_wallet);
     bool res = true;
     for (auto spk_man : GetActiveScriptPubKeyMans()) {
         res &= spk_man->TopUp(kpSize);
     }
     return res;
 }
 
 bool CWallet::GetNewDestination(const OutputType type, const std::string label,
                                 CTxDestination &dest, std::string &error) {
     LOCK(cs_wallet);
     error.clear();
     bool result = false;
     auto spk_man = GetScriptPubKeyMan(type, false /* internal */);
     if (spk_man) {
         spk_man->TopUp();
         result = spk_man->GetNewDestination(type, dest, error);
     }
     if (result) {
         SetAddressBook(dest, label, "receive");
     }
 
     return result;
 }
 
 bool CWallet::GetNewChangeDestination(const OutputType type,
                                       CTxDestination &dest,
                                       std::string &error) {
     LOCK(cs_wallet);
     error.clear();
 
     ReserveDestination reservedest(this, type);
     if (!reservedest.GetReservedDestination(dest, true)) {
         error = "Error: Keypool ran out, please call keypoolrefill first";
         return false;
     }
 
     reservedest.KeepDestination();
     return true;
 }
 
 int64_t CWallet::GetOldestKeyPoolTime() {
     LOCK(cs_wallet);
     int64_t oldestKey = std::numeric_limits<int64_t>::max();
     for (const auto &spk_man_pair : m_spk_managers) {
         oldestKey =
             std::min(oldestKey, spk_man_pair.second->GetOldestKeyPoolTime());
     }
     return oldestKey;
 }
 
 void CWallet::MarkDestinationsDirty(
     const std::set<CTxDestination> &destinations) {
     for (auto &entry : mapWallet) {
         CWalletTx &wtx = entry.second;
         if (wtx.m_is_cache_empty) {
             continue;
         }
 
         for (size_t i = 0; i < wtx.tx->vout.size(); i++) {
             CTxDestination dst;
 
             if (ExtractDestination(wtx.tx->vout[i].scriptPubKey, dst) &&
                 destinations.count(dst)) {
                 wtx.MarkDirty();
                 break;
             }
         }
     }
 }
 
 std::map<CTxDestination, Amount>
 CWallet::GetAddressBalances(interfaces::Chain::Lock &locked_chain) {
     std::map<CTxDestination, Amount> balances;
 
     LOCK(cs_wallet);
     std::set<TxId> trusted_parents;
     for (const auto &walletEntry : mapWallet) {
         const CWalletTx &wtx = walletEntry.second;
 
         if (!wtx.IsTrusted(locked_chain, trusted_parents)) {
             continue;
         }
 
         if (wtx.IsImmatureCoinBase()) {
             continue;
         }
 
         int nDepth = wtx.GetDepthInMainChain();
         if (nDepth < (wtx.IsFromMe(ISMINE_ALL) ? 0 : 1)) {
             continue;
         }
 
         for (uint32_t i = 0; i < wtx.tx->vout.size(); i++) {
             CTxDestination addr;
             if (!IsMine(wtx.tx->vout[i])) {
                 continue;
             }
 
             if (!ExtractDestination(wtx.tx->vout[i].scriptPubKey, addr)) {
                 continue;
             }
 
             Amount n = IsSpent(COutPoint(walletEntry.first, i))
                            ? Amount::zero()
                            : wtx.tx->vout[i].nValue;
 
             if (!balances.count(addr)) {
                 balances[addr] = Amount::zero();
             }
             balances[addr] += n;
         }
     }
 
     return balances;
 }
 
 std::set<std::set<CTxDestination>> CWallet::GetAddressGroupings() {
     AssertLockHeld(cs_wallet);
     std::set<std::set<CTxDestination>> groupings;
     std::set<CTxDestination> grouping;
 
     for (const auto &walletEntry : mapWallet) {
         const CWalletTx &wtx = walletEntry.second;
 
         if (wtx.tx->vin.size() > 0) {
             bool any_mine = false;
             // Group all input addresses with each other.
             for (const auto &txin : wtx.tx->vin) {
                 CTxDestination address;
                 // If this input isn't mine, ignore it.
                 if (!IsMine(txin)) {
                     continue;
                 }
 
                 if (!ExtractDestination(mapWallet.at(txin.prevout.GetTxId())
                                             .tx->vout[txin.prevout.GetN()]
                                             .scriptPubKey,
                                         address)) {
                     continue;
                 }
 
                 grouping.insert(address);
                 any_mine = true;
             }
 
             // Group change with input addresses.
             if (any_mine) {
                 for (const auto &txout : wtx.tx->vout) {
                     if (IsChange(txout)) {
                         CTxDestination txoutAddr;
                         if (!ExtractDestination(txout.scriptPubKey,
                                                 txoutAddr)) {
                             continue;
                         }
 
                         grouping.insert(txoutAddr);
                     }
                 }
             }
 
             if (grouping.size() > 0) {
                 groupings.insert(grouping);
                 grouping.clear();
             }
         }
 
         // Group lone addrs by themselves.
         for (const auto &txout : wtx.tx->vout) {
             if (IsMine(txout)) {
                 CTxDestination address;
                 if (!ExtractDestination(txout.scriptPubKey, address)) {
                     continue;
                 }
 
                 grouping.insert(address);
                 groupings.insert(grouping);
                 grouping.clear();
             }
         }
     }
 
     // A set of pointers to groups of addresses.
     std::set<std::set<CTxDestination> *> uniqueGroupings;
     // Map addresses to the unique group containing it.
     std::map<CTxDestination, std::set<CTxDestination> *> setmap;
     for (std::set<CTxDestination> _grouping : groupings) {
         // Make a set of all the groups hit by this new group.
         std::set<std::set<CTxDestination> *> hits;
         std::map<CTxDestination, std::set<CTxDestination> *>::iterator it;
         for (const CTxDestination &address : _grouping) {
             if ((it = setmap.find(address)) != setmap.end()) {
                 hits.insert((*it).second);
             }
         }
 
         // Merge all hit groups into a new single group and delete old groups.
         std::set<CTxDestination> *merged =
             new std::set<CTxDestination>(_grouping);
         for (std::set<CTxDestination> *hit : hits) {
             merged->insert(hit->begin(), hit->end());
             uniqueGroupings.erase(hit);
             delete hit;
         }
         uniqueGroupings.insert(merged);
 
         // Update setmap.
         for (const CTxDestination &element : *merged) {
             setmap[element] = merged;
         }
     }
 
     std::set<std::set<CTxDestination>> ret;
     for (const std::set<CTxDestination> *uniqueGrouping : uniqueGroupings) {
         ret.insert(*uniqueGrouping);
         delete uniqueGrouping;
     }
 
     return ret;
 }
 
 std::set<CTxDestination>
 CWallet::GetLabelAddresses(const std::string &label) const {
     LOCK(cs_wallet);
     std::set<CTxDestination> result;
     for (const std::pair<const CTxDestination, CAddressBookData> &item :
          m_address_book) {
         if (item.second.IsChange()) {
             continue;
         }
         const CTxDestination &address = item.first;
         const std::string &strName = item.second.GetLabel();
         if (strName == label) {
             result.insert(address);
         }
     }
 
     return result;
 }
 
 bool ReserveDestination::GetReservedDestination(CTxDestination &dest,
                                                 bool internal) {
     m_spk_man = pwallet->GetScriptPubKeyMan(type, internal);
     if (!m_spk_man) {
         return false;
     }
 
     if (nIndex == -1) {
         m_spk_man->TopUp();
 
         CKeyPool keypool;
         if (!m_spk_man->GetReservedDestination(type, internal, address, nIndex,
                                                keypool)) {
             return false;
         }
         fInternal = keypool.fInternal;
     }
     dest = address;
     return true;
 }
 
 void ReserveDestination::KeepDestination() {
     if (nIndex != -1) {
         m_spk_man->KeepDestination(nIndex, type);
     }
 
     nIndex = -1;
     address = CNoDestination();
 }
 
 void ReserveDestination::ReturnDestination() {
     if (nIndex != -1) {
         m_spk_man->ReturnDestination(nIndex, fInternal, address);
     }
     nIndex = -1;
     address = CNoDestination();
 }
 
 void CWallet::LockCoin(const COutPoint &output) {
     AssertLockHeld(cs_wallet);
     setLockedCoins.insert(output);
 }
 
 void CWallet::UnlockCoin(const COutPoint &output) {
     AssertLockHeld(cs_wallet);
     setLockedCoins.erase(output);
 }
 
 void CWallet::UnlockAllCoins() {
     AssertLockHeld(cs_wallet);
     setLockedCoins.clear();
 }
 
 bool CWallet::IsLockedCoin(const COutPoint &outpoint) const {
     AssertLockHeld(cs_wallet);
 
     return setLockedCoins.count(outpoint) > 0;
 }
 
 void CWallet::ListLockedCoins(std::vector<COutPoint> &vOutpts) const {
     AssertLockHeld(cs_wallet);
     for (COutPoint outpoint : setLockedCoins) {
         vOutpts.push_back(outpoint);
     }
 }
 
 /** @} */ // end of Actions
 
 void CWallet::GetKeyBirthTimes(interfaces::Chain::Lock &locked_chain,
                                std::map<CKeyID, int64_t> &mapKeyBirth) const {
     AssertLockHeld(cs_wallet);
     mapKeyBirth.clear();
 
     LegacyScriptPubKeyMan *spk_man = GetLegacyScriptPubKeyMan();
     assert(spk_man != nullptr);
     LOCK(spk_man->cs_KeyStore);
 
     // Get birth times for keys with metadata.
     for (const auto &entry : spk_man->mapKeyMetadata) {
         if (entry.second.nCreateTime) {
             mapKeyBirth[entry.first] = entry.second.nCreateTime;
         }
     }
 
     // Map in which we'll infer heights of other keys
     const Optional<int> tip_height = locked_chain.getHeight();
     // the tip can be reorganized; use a 144-block safety margin
     const int max_height =
         tip_height && *tip_height > 144 ? *tip_height - 144 : 0;
     std::map<CKeyID, int> mapKeyFirstBlock;
     for (const CKeyID &keyid : spk_man->GetKeys()) {
         if (mapKeyBirth.count(keyid) == 0) {
             mapKeyFirstBlock[keyid] = max_height;
         }
     }
 
     // If there are no such keys, we're done.
     if (mapKeyFirstBlock.empty()) {
         return;
     }
 
     // Find first block that affects those keys, if there are any left.
     for (const auto &entry : mapWallet) {
         // iterate over all wallet transactions...
         const CWalletTx &wtx = entry.second;
         if (Optional<int> height =
                 locked_chain.getBlockHeight(wtx.m_confirm.hashBlock)) {
             // ... which are already in a block
             for (const CTxOut &txout : wtx.tx->vout) {
                 // Iterate over all their outputs...
                 for (const auto &keyid :
                      GetAffectedKeys(txout.scriptPubKey, *spk_man)) {
                     // ... and all their affected keys.
                     std::map<CKeyID, int>::iterator rit =
                         mapKeyFirstBlock.find(keyid);
                     if (rit != mapKeyFirstBlock.end() &&
                         *height < rit->second) {
                         rit->second = *height;
                     }
                 }
             }
         }
     }
 
     // Extract block timestamps for those keys.
     for (const auto &entry : mapKeyFirstBlock) {
         // block times can be 2h off
         mapKeyBirth[entry.first] =
             locked_chain.getBlockTime(entry.second) - TIMESTAMP_WINDOW;
     }
 }
 
 /**
  * Compute smart timestamp for a transaction being added to the wallet.
  *
  * Logic:
  * - If sending a transaction, assign its timestamp to the current time.
  * - If receiving a transaction outside a block, assign its timestamp to the
  *   current time.
  * - If receiving a block with a future timestamp, assign all its (not already
  *   known) transactions' timestamps to the current time.
  * - If receiving a block with a past timestamp, before the most recent known
  *   transaction (that we care about), assign all its (not already known)
  *   transactions' timestamps to the same timestamp as that most-recent-known
  *   transaction.
  * - If receiving a block with a past timestamp, but after the most recent known
  *   transaction, assign all its (not already known) transactions' timestamps to
  *   the block time.
  *
  * For more information see CWalletTx::nTimeSmart,
  * https://bitcointalk.org/?topic=54527, or
  * https://github.com/bitcoin/bitcoin/pull/1393.
  */
 unsigned int CWallet::ComputeTimeSmart(const CWalletTx &wtx) const {
     unsigned int nTimeSmart = wtx.nTimeReceived;
     if (!wtx.isUnconfirmed() && !wtx.isAbandoned()) {
         int64_t blocktime;
-        if (chain().findBlock(wtx.m_confirm.hashBlock, nullptr /* block */,
-                              &blocktime)) {
+        if (chain().findBlock(wtx.m_confirm.hashBlock,
+                              FoundBlock().time(blocktime))) {
             int64_t latestNow = wtx.nTimeReceived;
             int64_t latestEntry = 0;
 
             // Tolerate times up to the last timestamp in the wallet not more
             // than 5 minutes into the future
             int64_t latestTolerated = latestNow + 300;
             const TxItems &txOrdered = wtxOrdered;
             for (auto it = txOrdered.rbegin(); it != txOrdered.rend(); ++it) {
                 CWalletTx *const pwtx = it->second;
                 if (pwtx == &wtx) {
                     continue;
                 }
                 int64_t nSmartTime;
                 nSmartTime = pwtx->nTimeSmart;
                 if (!nSmartTime) {
                     nSmartTime = pwtx->nTimeReceived;
                 }
                 if (nSmartTime <= latestTolerated) {
                     latestEntry = nSmartTime;
                     if (nSmartTime > latestNow) {
                         latestNow = nSmartTime;
                     }
                     break;
                 }
             }
 
             nTimeSmart = std::max(latestEntry, std::min(blocktime, latestNow));
         } else {
             WalletLogPrintf("%s: found %s in block %s not in index\n", __func__,
                             wtx.GetId().ToString(),
                             wtx.m_confirm.hashBlock.ToString());
         }
     }
     return nTimeSmart;
 }
 
 bool CWallet::AddDestData(WalletBatch &batch, const CTxDestination &dest,
                           const std::string &key, const std::string &value) {
     if (boost::get<CNoDestination>(&dest)) {
         return false;
     }
 
     m_address_book[dest].destdata.insert(std::make_pair(key, value));
     return batch.WriteDestData(dest, key, value);
 }
 
 bool CWallet::EraseDestData(WalletBatch &batch, const CTxDestination &dest,
                             const std::string &key) {
     if (!m_address_book[dest].destdata.erase(key)) {
         return false;
     }
 
     return batch.EraseDestData(dest, key);
 }
 
 void CWallet::LoadDestData(const CTxDestination &dest, const std::string &key,
                            const std::string &value) {
     m_address_book[dest].destdata.insert(std::make_pair(key, value));
 }
 
 bool CWallet::GetDestData(const CTxDestination &dest, const std::string &key,
                           std::string *value) const {
     std::map<CTxDestination, CAddressBookData>::const_iterator i =
         m_address_book.find(dest);
     if (i != m_address_book.end()) {
         CAddressBookData::StringMap::const_iterator j =
             i->second.destdata.find(key);
         if (j != i->second.destdata.end()) {
             if (value) {
                 *value = j->second;
             }
 
             return true;
         }
     }
     return false;
 }
 
 std::vector<std::string>
 CWallet::GetDestValues(const std::string &prefix) const {
     std::vector<std::string> values;
     for (const auto &address : m_address_book) {
         for (const auto &data : address.second.destdata) {
             if (!data.first.compare(0, prefix.size(), prefix)) {
                 values.emplace_back(data.second);
             }
         }
     }
     return values;
 }
 
 bool CWallet::Verify(const CChainParams &chainParams, interfaces::Chain &chain,
                      const WalletLocation &location, bool salvage_wallet,
                      bilingual_str &error_string,
                      std::vector<bilingual_str> &warnings) {
     // Do some checking on wallet path. It should be either a:
     //
     // 1. Path where a directory can be created.
     // 2. Path to an existing directory.
     // 3. Path to a symlink to a directory.
     // 4. For backwards compatibility, the name of a data file in -walletdir.
     LOCK(cs_wallets);
     const fs::path &wallet_path = location.GetPath();
     fs::file_type path_type = fs::symlink_status(wallet_path).type();
     if (!(path_type == fs::file_not_found || path_type == fs::directory_file ||
           (path_type == fs::symlink_file && fs::is_directory(wallet_path)) ||
           (path_type == fs::regular_file &&
            fs::path(location.GetName()).filename() == location.GetName()))) {
         error_string = Untranslated(
             strprintf("Invalid -wallet path '%s'. -wallet path should point to "
                       "a directory where wallet.dat and "
                       "database/log.?????????? files can be stored, a location "
                       "where such a directory could be created, "
                       "or (for backwards compatibility) the name of an "
                       "existing data file in -walletdir (%s)",
                       location.GetName(), GetWalletDir()));
         return false;
     }
 
     // Make sure that the wallet path doesn't clash with an existing wallet path
     if (IsWalletLoaded(wallet_path)) {
         error_string = Untranslated(strprintf(
             "Error loading wallet %s. Duplicate -wallet filename specified.",
             location.GetName()));
         return false;
     }
 
     // Keep same database environment instance across Verify/Recover calls
     // below.
     std::unique_ptr<WalletDatabase> database =
         WalletDatabase::Create(wallet_path);
 
     try {
         if (!WalletBatch::VerifyEnvironment(wallet_path, error_string)) {
             return false;
         }
     } catch (const fs::filesystem_error &e) {
         error_string = Untranslated(
             strprintf("Error loading wallet %s. %s", location.GetName(),
                       fsbridge::get_filesystem_error_message(e)));
         return false;
     }
 
     if (salvage_wallet) {
         // Recover readable keypairs:
         CWallet dummyWallet(chainParams, &chain, WalletLocation(),
                             WalletDatabase::CreateDummy());
         std::string backup_filename;
         // Even if we don't use this lock in this function, we want to preserve
         // lock order in LoadToWallet if query of chain state is needed to know
         // tx status. If lock can't be taken, tx confirmation status may be not
         // reliable.
         auto locked_chain = dummyWallet.LockChain();
         if (!WalletBatch::Recover(
                 wallet_path, static_cast<void *>(&dummyWallet),
                 WalletBatch::RecoverKeysOnlyFilter, backup_filename)) {
             return false;
         }
     }
 
     return WalletBatch::VerifyDatabaseFile(wallet_path, warnings, error_string);
 }
 
 std::shared_ptr<CWallet> CWallet::CreateWalletFromFile(
     const CChainParams &chainParams, interfaces::Chain &chain,
     const WalletLocation &location, bilingual_str &error,
     std::vector<bilingual_str> &warnings, uint64_t wallet_creation_flags) {
     const std::string walletFile =
         WalletDataFilePath(location.GetPath()).string();
 
     // Needed to restore wallet transaction meta data after -zapwallettxes
     std::vector<CWalletTx> vWtx;
 
     if (gArgs.GetBoolArg("-zapwallettxes", false)) {
         chain.initMessage(
             _("Zapping all transactions from wallet...").translated);
 
         std::unique_ptr<CWallet> tempWallet = std::make_unique<CWallet>(
             chainParams, &chain, location,
             WalletDatabase::Create(location.GetPath()));
         DBErrors nZapWalletRet = tempWallet->ZapWalletTx(vWtx);
         if (nZapWalletRet != DBErrors::LOAD_OK) {
             error =
                 strprintf(_("Error loading %s: Wallet corrupted"), walletFile);
             return nullptr;
         }
     }
 
     chain.initMessage(_("Loading wallet...").translated);
 
     int64_t nStart = GetTimeMillis();
     bool fFirstRun = true;
     // TODO: Can't use std::make_shared because we need a custom deleter but
     // should be possible to use std::allocate_shared.
     std::shared_ptr<CWallet> walletInstance(
         new CWallet(chainParams, &chain, location,
                     WalletDatabase::Create(location.GetPath())),
         ReleaseWallet);
     DBErrors nLoadWalletRet = walletInstance->LoadWallet(fFirstRun);
     if (nLoadWalletRet != DBErrors::LOAD_OK) {
         if (nLoadWalletRet == DBErrors::CORRUPT) {
             error =
                 strprintf(_("Error loading %s: Wallet corrupted"), walletFile);
             return nullptr;
         }
 
         if (nLoadWalletRet == DBErrors::NONCRITICAL_ERROR) {
             warnings.push_back(
                 strprintf(_("Error reading %s! All keys read correctly, but "
                             "transaction data or address book entries might be "
                             "missing or incorrect."),
                           walletFile));
         } else if (nLoadWalletRet == DBErrors::TOO_NEW) {
             error = strprintf(
                 _("Error loading %s: Wallet requires newer version of %s"),
                 walletFile, PACKAGE_NAME);
             return nullptr;
         } else if (nLoadWalletRet == DBErrors::NEED_REWRITE) {
             error = strprintf(
                 _("Wallet needed to be rewritten: restart %s to complete"),
                 PACKAGE_NAME);
             return nullptr;
         } else {
             error = strprintf(_("Error loading %s"), walletFile);
             return nullptr;
         }
     }
 
     int prev_version = walletInstance->GetVersion();
     if (gArgs.GetBoolArg("-upgradewallet", fFirstRun)) {
         int nMaxVersion = gArgs.GetArg("-upgradewallet", 0);
         // The -upgradewallet without argument case
         if (nMaxVersion == 0) {
             walletInstance->WalletLogPrintf("Performing wallet upgrade to %i\n",
                                             FEATURE_LATEST);
             nMaxVersion = FEATURE_LATEST;
             // permanently upgrade the wallet immediately
             walletInstance->SetMinVersion(FEATURE_LATEST);
         } else {
             walletInstance->WalletLogPrintf(
                 "Allowing wallet upgrade up to %i\n", nMaxVersion);
         }
 
         if (nMaxVersion < walletInstance->GetVersion()) {
             error = _("Cannot downgrade wallet");
             return nullptr;
         }
 
         walletInstance->SetMaxVersion(nMaxVersion);
     }
 
     // Upgrade to HD if explicit upgrade
     if (gArgs.GetBoolArg("-upgradewallet", false)) {
         LOCK(walletInstance->cs_wallet);
 
         // Do not upgrade versions to any version between HD_SPLIT and
         // FEATURE_PRE_SPLIT_KEYPOOL unless already supporting HD_SPLIT
         int max_version = walletInstance->GetVersion();
         if (!walletInstance->CanSupportFeature(FEATURE_HD_SPLIT) &&
             max_version >= FEATURE_HD_SPLIT &&
             max_version < FEATURE_PRE_SPLIT_KEYPOOL) {
             error =
                 _("Cannot upgrade a non HD split wallet without upgrading to "
                   "support pre split keypool. Please use -upgradewallet=200300 "
                   "or -upgradewallet with no version specified.");
             return nullptr;
         }
 
         for (auto spk_man : walletInstance->GetActiveScriptPubKeyMans()) {
             if (!spk_man->Upgrade(prev_version, error)) {
                 return nullptr;
             }
         }
     }
 
     if (fFirstRun) {
         // Ensure this wallet.dat can only be opened by clients supporting
         // HD with chain split and expects no default key.
         walletInstance->SetMinVersion(FEATURE_LATEST);
 
         walletInstance->SetWalletFlags(wallet_creation_flags, false);
 
         // Always create LegacyScriptPubKeyMan for now
         walletInstance->SetupLegacyScriptPubKeyMan();
 
         if (!(wallet_creation_flags &
               (WALLET_FLAG_DISABLE_PRIVATE_KEYS | WALLET_FLAG_BLANK_WALLET))) {
             LOCK(walletInstance->cs_wallet);
             for (auto spk_man : walletInstance->GetActiveScriptPubKeyMans()) {
                 if (!spk_man->SetupGeneration()) {
                     error = _("Unable to generate initial keys");
                     return nullptr;
                 }
             }
         }
 
         auto locked_chain = chain.lock();
         walletInstance->ChainStateFlushed(locked_chain->getTipLocator());
     } else if (wallet_creation_flags & WALLET_FLAG_DISABLE_PRIVATE_KEYS) {
         // Make it impossible to disable private keys after creation
         error = strprintf(_("Error loading %s: Private keys can only be "
                             "disabled during creation"),
                           walletFile);
         return nullptr;
     } else if (walletInstance->IsWalletFlagSet(
                    WALLET_FLAG_DISABLE_PRIVATE_KEYS)) {
         for (auto spk_man : walletInstance->GetActiveScriptPubKeyMans()) {
             if (spk_man->HavePrivateKeys()) {
                 warnings.push_back(
                     strprintf(_("Warning: Private keys detected in wallet {%s} "
                                 "with disabled private keys"),
                               walletFile));
             }
         }
     }
 
     if (gArgs.IsArgSet("-mintxfee")) {
         Amount n = Amount::zero();
         if (!ParseMoney(gArgs.GetArg("-mintxfee", ""), n) ||
             n == Amount::zero()) {
             error = AmountErrMsg("mintxfee", gArgs.GetArg("-mintxfee", ""));
             return nullptr;
         }
         if (n > HIGH_TX_FEE_PER_KB) {
             warnings.push_back(AmountHighWarn("-mintxfee") + Untranslated(" ") +
                                _("This is the minimum transaction fee you pay "
                                  "on every transaction."));
         }
         walletInstance->m_min_fee = CFeeRate(n);
     }
 
     if (gArgs.IsArgSet("-maxapsfee")) {
         Amount n = Amount::zero();
         if (gArgs.GetArg("-maxapsfee", "") == "-1") {
             n = -1 * SATOSHI;
         } else if (!ParseMoney(gArgs.GetArg("-maxapsfee", ""), n)) {
             error = AmountErrMsg("maxapsfee", gArgs.GetArg("-maxapsfee", ""));
             return nullptr;
         }
         if (n > HIGH_APS_FEE) {
             warnings.push_back(
                 AmountHighWarn("-maxapsfee") + Untranslated(" ") +
                 _("This is the maximum transaction fee you pay to prioritize "
                   "partial spend avoidance over regular coin selection."));
         }
         walletInstance->m_max_aps_fee = n;
     }
 
     if (gArgs.IsArgSet("-fallbackfee")) {
         Amount nFeePerK = Amount::zero();
         if (!ParseMoney(gArgs.GetArg("-fallbackfee", ""), nFeePerK)) {
             error =
                 strprintf(_("Invalid amount for -fallbackfee=<amount>: '%s'"),
                           gArgs.GetArg("-fallbackfee", ""));
             return nullptr;
         }
         if (nFeePerK > HIGH_TX_FEE_PER_KB) {
             warnings.push_back(AmountHighWarn("-fallbackfee") +
                                Untranslated(" ") +
                                _("This is the transaction fee you may pay when "
                                  "fee estimates are not available."));
         }
         walletInstance->m_fallback_fee = CFeeRate(nFeePerK);
     }
     // Disable fallback fee in case value was set to 0, enable if non-null value
     walletInstance->m_allow_fallback_fee =
         walletInstance->m_fallback_fee.GetFeePerK() != Amount::zero();
 
     if (gArgs.IsArgSet("-paytxfee")) {
         Amount nFeePerK = Amount::zero();
         if (!ParseMoney(gArgs.GetArg("-paytxfee", ""), nFeePerK)) {
             error = AmountErrMsg("paytxfee", gArgs.GetArg("-paytxfee", ""));
             return nullptr;
         }
         if (nFeePerK > HIGH_TX_FEE_PER_KB) {
             warnings.push_back(AmountHighWarn("-paytxfee") + Untranslated(" ") +
                                _("This is the transaction fee you will pay if "
                                  "you send a transaction."));
         }
         walletInstance->m_pay_tx_fee = CFeeRate(nFeePerK, 1000);
         if (walletInstance->m_pay_tx_fee < chain.relayMinFee()) {
             error = strprintf(_("Invalid amount for -paytxfee=<amount>: '%s' "
                                 "(must be at least %s)"),
                               gArgs.GetArg("-paytxfee", ""),
                               chain.relayMinFee().ToString());
             return nullptr;
         }
     }
 
     if (gArgs.IsArgSet("-maxtxfee")) {
         Amount nMaxFee = Amount::zero();
         if (!ParseMoney(gArgs.GetArg("-maxtxfee", ""), nMaxFee)) {
             error = AmountErrMsg("maxtxfee", gArgs.GetArg("-maxtxfee", ""));
             return nullptr;
         }
         if (nMaxFee > HIGH_MAX_TX_FEE) {
             warnings.push_back(_("-maxtxfee is set very high! Fees this large "
                                  "could be paid on a single transaction."));
         }
         if (CFeeRate(nMaxFee, 1000) < chain.relayMinFee()) {
             error = strprintf(
                 _("Invalid amount for -maxtxfee=<amount>: '%s' (must be at "
                   "least the minrelay fee of %s to prevent stuck "
                   "transactions)"),
                 gArgs.GetArg("-maxtxfee", ""), chain.relayMinFee().ToString());
             return nullptr;
         }
         walletInstance->m_default_max_tx_fee = nMaxFee;
     }
 
     if (chain.relayMinFee().GetFeePerK() > HIGH_TX_FEE_PER_KB) {
         warnings.push_back(
             AmountHighWarn("-minrelaytxfee") + Untranslated(" ") +
             _("The wallet will avoid paying less than the minimum relay fee."));
     }
 
     walletInstance->m_spend_zero_conf_change =
         gArgs.GetBoolArg("-spendzeroconfchange", DEFAULT_SPEND_ZEROCONF_CHANGE);
 
     walletInstance->m_default_address_type = DEFAULT_ADDRESS_TYPE;
     walletInstance->m_default_change_type = DEFAULT_CHANGE_TYPE;
 
     walletInstance->WalletLogPrintf("Wallet completed loading in %15dms\n",
                                     GetTimeMillis() - nStart);
 
     // Try to top up keypool. No-op if the wallet is locked.
     walletInstance->TopUpKeyPool();
 
     auto locked_chain = chain.lock();
     LOCK(walletInstance->cs_wallet);
 
     int rescan_height = 0;
     if (!gArgs.GetBoolArg("-rescan", false)) {
         WalletBatch batch(*walletInstance->database);
         CBlockLocator locator;
         if (batch.ReadBestBlock(locator)) {
             if (const Optional<int> fork_height =
                     locked_chain->findLocatorFork(locator)) {
                 rescan_height = *fork_height;
             }
         }
     }
 
     const Optional<int> tip_height = locked_chain->getHeight();
     if (tip_height) {
         walletInstance->m_last_block_processed =
             locked_chain->getBlockHash(*tip_height);
         walletInstance->m_last_block_processed_height = *tip_height;
     } else {
         walletInstance->m_last_block_processed.SetNull();
         walletInstance->m_last_block_processed_height = -1;
     }
 
     if (tip_height && *tip_height != rescan_height) {
         // We can't rescan beyond non-pruned blocks, stop and throw an error.
         // This might happen if a user uses an old wallet within a pruned node
         // or if they ran -disablewallet for a longer time, then decided to
         // re-enable
         if (chain.havePruned()) {
             // Exit early and print an error.
             // If a block is pruned after this check, we will load the wallet,
             // but fail the rescan with a generic error.
             int block_height = *tip_height;
             while (block_height > 0 &&
                    locked_chain->haveBlockOnDisk(block_height - 1) &&
                    rescan_height != block_height) {
                 --block_height;
             }
 
             if (rescan_height != block_height) {
                 error = _("Prune: last wallet synchronisation goes beyond "
                           "pruned data. You need to -reindex (download the "
                           "whole blockchain again in case of pruned node)");
                 return nullptr;
             }
         }
 
         chain.initMessage(_("Rescanning...").translated);
         walletInstance->WalletLogPrintf(
             "Rescanning last %i blocks (from block %i)...\n",
             *tip_height - rescan_height, rescan_height);
 
         // No need to read and scan block if block was created before our wallet
         // birthday (as adjusted for block time variability)
         // The way the 'time_first_key' is initialized is just a workaround for
         // the gcc bug #47679 since version 4.6.0.
         Optional<int64_t> time_first_key = MakeOptional(false, int64_t());
         for (auto spk_man : walletInstance->GetAllScriptPubKeyMans()) {
             int64_t time = spk_man->GetTimeFirstKey();
             if (!time_first_key || time < *time_first_key) {
                 time_first_key = time;
             }
         }
         if (time_first_key) {
             if (Optional<int> first_block =
                     locked_chain->findFirstBlockWithTimeAndHeight(
                         *time_first_key - TIMESTAMP_WINDOW, rescan_height,
                         nullptr)) {
                 rescan_height = *first_block;
             }
         }
 
         {
             WalletRescanReserver reserver(*walletInstance);
             if (!reserver.reserve() ||
                 (ScanResult::SUCCESS !=
                  walletInstance
                      ->ScanForWalletTransactions(
                          locked_chain->getBlockHash(rescan_height), BlockHash(),
                          reserver, true /* update */)
                      .status)) {
                 error = _("Failed to rescan the wallet during initialization");
                 return nullptr;
             }
         }
         walletInstance->ChainStateFlushed(locked_chain->getTipLocator());
         walletInstance->database->IncrementUpdateCounter();
 
         // Restore wallet transaction metadata after -zapwallettxes=1
         if (gArgs.GetBoolArg("-zapwallettxes", false) &&
             gArgs.GetArg("-zapwallettxes", "1") != "2") {
             WalletBatch batch(*walletInstance->database);
 
             for (const CWalletTx &wtxOld : vWtx) {
                 const TxId txid = wtxOld.GetId();
                 std::map<TxId, CWalletTx>::iterator mi =
                     walletInstance->mapWallet.find(txid);
                 if (mi != walletInstance->mapWallet.end()) {
                     const CWalletTx *copyFrom = &wtxOld;
                     CWalletTx *copyTo = &mi->second;
                     copyTo->mapValue = copyFrom->mapValue;
                     copyTo->vOrderForm = copyFrom->vOrderForm;
                     copyTo->nTimeReceived = copyFrom->nTimeReceived;
                     copyTo->nTimeSmart = copyFrom->nTimeSmart;
                     copyTo->fFromMe = copyFrom->fFromMe;
                     copyTo->nOrderPos = copyFrom->nOrderPos;
                     batch.WriteTx(*copyTo);
                 }
             }
         }
     }
 
     {
         LOCK(cs_wallets);
         for (auto &load_wallet : g_load_wallet_fns) {
             load_wallet(interfaces::MakeWallet(walletInstance));
         }
     }
 
     // Register with the validation interface. It's ok to do this after rescan
     // since we're still holding locked_chain.
     walletInstance->m_chain_notifications_handler =
         walletInstance->chain().handleNotifications(walletInstance);
 
     walletInstance->SetBroadcastTransactions(
         gArgs.GetBoolArg("-walletbroadcast", DEFAULT_WALLETBROADCAST));
 
     walletInstance->WalletLogPrintf("setKeyPool.size() = %u\n",
                                     walletInstance->GetKeyPoolSize());
     walletInstance->WalletLogPrintf("mapWallet.size() = %u\n",
                                     walletInstance->mapWallet.size());
     walletInstance->WalletLogPrintf("m_address_book.size() = %u\n",
                                     walletInstance->m_address_book.size());
 
     return walletInstance;
 }
 
 const CAddressBookData *
 CWallet::FindAddressBookEntry(const CTxDestination &dest,
                               bool allow_change) const {
     const auto &address_book_it = m_address_book.find(dest);
     if (address_book_it == m_address_book.end()) {
         return nullptr;
     }
     if ((!allow_change) && address_book_it->second.IsChange()) {
         return nullptr;
     }
     return &address_book_it->second;
 }
 
 void CWallet::postInitProcess() {
     auto locked_chain = chain().lock();
     LOCK(cs_wallet);
 
     // Add wallet transactions that aren't already in a block to mempool.
     // Do this here as mempool requires genesis block to be loaded.
     ReacceptWalletTransactions();
 
     // Update wallet transactions with current mempool transactions.
     chain().requestMempoolTransactions(*this);
 }
 
 bool CWallet::BackupWallet(const std::string &strDest) {
     return database->Backup(strDest);
 }
 
 CKeyPool::CKeyPool() {
     nTime = GetTime();
     fInternal = false;
     m_pre_split = false;
 }
 
 CKeyPool::CKeyPool(const CPubKey &vchPubKeyIn, bool internalIn) {
     nTime = GetTime();
     vchPubKey = vchPubKeyIn;
     fInternal = internalIn;
     m_pre_split = false;
 }
 
 int CWalletTx::GetDepthInMainChain() const {
     assert(pwallet != nullptr);
     AssertLockHeld(pwallet->cs_wallet);
     if (isUnconfirmed() || isAbandoned()) {
         return 0;
     }
 
     return (pwallet->GetLastBlockHeight() - m_confirm.block_height + 1) *
            (isConflicted() ? -1 : 1);
 }
 
 int CWalletTx::GetBlocksToMaturity() const {
     if (!IsCoinBase()) {
         return 0;
     }
 
     int chain_depth = GetDepthInMainChain();
     // coinbase tx should not be conflicted
     assert(chain_depth >= 0);
     return std::max(0, (COINBASE_MATURITY + 1) - chain_depth);
 }
 
 bool CWalletTx::IsImmatureCoinBase() const {
     // note GetBlocksToMaturity is 0 for non-coinbase tx
     return GetBlocksToMaturity() > 0;
 }
 
 std::vector<OutputGroup>
 CWallet::GroupOutputs(const std::vector<COutput> &outputs, bool single_coin,
                       const size_t max_ancestors) const {
     std::vector<OutputGroup> groups;
     std::map<CTxDestination, OutputGroup> gmap;
     std::set<CTxDestination> full_groups;
 
     for (const auto &output : outputs) {
         if (output.fSpendable) {
             CTxDestination dst;
             CInputCoin input_coin = output.GetInputCoin();
 
             size_t ancestors, descendants;
             chain().getTransactionAncestry(output.tx->GetId(), ancestors,
                                            descendants);
             if (!single_coin &&
                 ExtractDestination(output.tx->tx->vout[output.i].scriptPubKey,
                                    dst)) {
                 auto it = gmap.find(dst);
                 if (it != gmap.end()) {
                     // Limit output groups to no more than
                     // OUTPUT_GROUP_MAX_ENTRIES number of entries, to protect
                     // against inadvertently creating a too-large transaction
                     // when using -avoidpartialspends to prevent breaking
                     // consensus or surprising users with a very high amount of
                     // fees.
                     if (it->second.m_outputs.size() >=
                         OUTPUT_GROUP_MAX_ENTRIES) {
                         groups.push_back(it->second);
                         it->second = OutputGroup{};
                         full_groups.insert(dst);
                     }
                     it->second.Insert(input_coin, output.nDepth,
                                       output.tx->IsFromMe(ISMINE_ALL),
                                       ancestors, descendants);
                 } else {
                     gmap[dst].Insert(input_coin, output.nDepth,
                                      output.tx->IsFromMe(ISMINE_ALL), ancestors,
                                      descendants);
                 }
             } else {
                 groups.emplace_back(input_coin, output.nDepth,
                                     output.tx->IsFromMe(ISMINE_ALL), ancestors,
                                     descendants);
             }
         }
     }
     if (!single_coin) {
         for (auto &it : gmap) {
             auto &group = it.second;
             if (full_groups.count(it.first) > 0) {
                 // Make this unattractive as we want coin selection to avoid it
                 // if possible
                 group.m_ancestors = max_ancestors - 1;
             }
             groups.push_back(group);
         }
     }
     return groups;
 }
 
 bool CWallet::IsCrypted() const {
     return HasEncryptionKeys();
 }
 
 bool CWallet::IsLocked() const {
     if (!IsCrypted()) {
         return false;
     }
     LOCK(cs_wallet);
     return vMasterKey.empty();
 }
 
 bool CWallet::Lock() {
     if (!IsCrypted()) {
         return false;
     }
 
     {
         LOCK(cs_wallet);
         vMasterKey.clear();
     }
 
     NotifyStatusChanged(this);
     return true;
 }
 
 bool CWallet::Unlock(const CKeyingMaterial &vMasterKeyIn, bool accept_no_keys) {
     {
         LOCK(cs_wallet);
         for (const auto &spk_man_pair : m_spk_managers) {
             if (!spk_man_pair.second->CheckDecryptionKey(vMasterKeyIn,
                                                          accept_no_keys)) {
                 return false;
             }
         }
         vMasterKey = vMasterKeyIn;
     }
     NotifyStatusChanged(this);
     return true;
 }
 
 std::set<ScriptPubKeyMan *> CWallet::GetActiveScriptPubKeyMans() const {
     std::set<ScriptPubKeyMan *> spk_mans;
     for (bool internal : {false, true}) {
         for (OutputType t : OUTPUT_TYPES) {
             auto spk_man = GetScriptPubKeyMan(t, internal);
             if (spk_man) {
                 spk_mans.insert(spk_man);
             }
         }
     }
     return spk_mans;
 }
 
 std::set<ScriptPubKeyMan *> CWallet::GetAllScriptPubKeyMans() const {
     std::set<ScriptPubKeyMan *> spk_mans;
     for (const auto &spk_man_pair : m_spk_managers) {
         spk_mans.insert(spk_man_pair.second.get());
     }
     return spk_mans;
 }
 
 ScriptPubKeyMan *CWallet::GetScriptPubKeyMan(const OutputType &type,
                                              bool internal) const {
     const std::map<OutputType, ScriptPubKeyMan *> &spk_managers =
         internal ? m_internal_spk_managers : m_external_spk_managers;
     std::map<OutputType, ScriptPubKeyMan *>::const_iterator it =
         spk_managers.find(type);
     if (it == spk_managers.end()) {
         WalletLogPrintf(
             "%s scriptPubKey Manager for output type %d does not exist\n",
             internal ? "Internal" : "External", static_cast<int>(type));
         return nullptr;
     }
     return it->second;
 }
 
 ScriptPubKeyMan *CWallet::GetScriptPubKeyMan(const CScript &script) const {
     SignatureData sigdata;
     for (const auto &spk_man_pair : m_spk_managers) {
         if (spk_man_pair.second->CanProvide(script, sigdata)) {
             return spk_man_pair.second.get();
         }
     }
     return nullptr;
 }
 
 ScriptPubKeyMan *CWallet::GetScriptPubKeyMan(const uint256 &id) const {
     if (m_spk_managers.count(id) > 0) {
         return m_spk_managers.at(id).get();
     }
     return nullptr;
 }
 
 std::unique_ptr<SigningProvider>
 CWallet::GetSigningProvider(const CScript &script) const {
     SignatureData sigdata;
     return GetSigningProvider(script, sigdata);
 }
 
 std::unique_ptr<SigningProvider>
 CWallet::GetSigningProvider(const CScript &script,
                             SignatureData &sigdata) const {
     for (const auto &spk_man_pair : m_spk_managers) {
         if (spk_man_pair.second->CanProvide(script, sigdata)) {
             return spk_man_pair.second->GetSigningProvider(script);
         }
     }
     return nullptr;
 }
 
 LegacyScriptPubKeyMan *CWallet::GetLegacyScriptPubKeyMan() const {
     // Legacy wallets only have one ScriptPubKeyMan which is a
     // LegacyScriptPubKeyMan. Everything in m_internal_spk_managers and
     // m_external_spk_managers point to the same legacyScriptPubKeyMan.
     auto it = m_internal_spk_managers.find(OutputType::LEGACY);
     if (it == m_internal_spk_managers.end()) {
         return nullptr;
     }
     return dynamic_cast<LegacyScriptPubKeyMan *>(it->second);
 }
 
 LegacyScriptPubKeyMan *CWallet::GetOrCreateLegacyScriptPubKeyMan() {
     SetupLegacyScriptPubKeyMan();
     return GetLegacyScriptPubKeyMan();
 }
 
 void CWallet::SetupLegacyScriptPubKeyMan() {
     if (!m_internal_spk_managers.empty() || !m_external_spk_managers.empty() ||
         !m_spk_managers.empty()) {
         return;
     }
 
     auto spk_manager =
         std::unique_ptr<ScriptPubKeyMan>(new LegacyScriptPubKeyMan(*this));
     for (const auto &type : OUTPUT_TYPES) {
         m_internal_spk_managers[type] = spk_manager.get();
         m_external_spk_managers[type] = spk_manager.get();
     }
     m_spk_managers[spk_manager->GetID()] = std::move(spk_manager);
 }
 
 const CKeyingMaterial &CWallet::GetEncryptionKey() const {
     return vMasterKey;
 }
 
 bool CWallet::HasEncryptionKeys() const {
     return !mapMasterKeys.empty();
 }
 
 void CWallet::ConnectScriptPubKeyManNotifiers() {
     for (const auto &spk_man : GetActiveScriptPubKeyMans()) {
         spk_man->NotifyWatchonlyChanged.connect(NotifyWatchonlyChanged);
         spk_man->NotifyCanGetAddressesChanged.connect(
             NotifyCanGetAddressesChanged);
     }
 }