diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 39a8f4191..b6f670111 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -1,4681 +1,4684 @@
 // 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 <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/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>
 
 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);
     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);
                 if (auto spk_man = wallet->m_spk_man.get()) {
                     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(uint256S(
     "0000000000000000000000000000000000000000000000000000000000000001"));
 
 /** @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;
     }
 
-    if (m_spk_man) {
-        m_spk_man->UpgradeKeyMetadata();
+    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);
 
         if (auto spk_man = m_spk_man.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 = m_spk_man.get()) {
             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) {
             if (auto spk_man = m_spk_man.get()) {
                 spk_man->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;
     if (auto spk_man = m_spk_man.get()) {
         result = spk_man->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;
     if (auto spk_man = m_spk_man.get()) {
         result &= spk_man->IsHDEnabled();
     }
     return result;
 }
 
 bool CWallet::CanGetAddresses(bool internal) {
     LOCK(cs_wallet);
     {
         auto spk_man = m_spk_man.get();
         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;
 
     const 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");
             }
             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()) {
             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;
             }
 
             const 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();
 
         const 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;
 
                 const 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")) {
             if (auto spk_man = m_spk_man.get()) {
                 spk_man->RewriteDB();
             }
         }
     }
 
     // This wallet is in its first run if there are no ScriptPubKeyMans and it
     // isn't blank or no privkeys
     {
         fFirstRunRet = !m_spk_man &&
                        !IsWalletFlagSet(WALLET_FLAG_DISABLE_PRIVATE_KEYS) &&
                        !IsWalletFlagSet(WALLET_FLAG_BLANK_WALLET);
     }
 
     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")) {
             if (auto spk_man = m_spk_man.get()) {
                 spk_man->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")) {
             if (auto spk_man = m_spk_man.get()) {
                 spk_man->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;
     if (auto spk_man = m_spk_man.get()) {
         count += spk_man->KeypoolCountExternalKeys();
     }
 
     return count;
 }
 
 unsigned int CWallet::GetKeyPoolSize() const {
     AssertLockHeld(cs_wallet);
 
     unsigned int count = 0;
     if (auto spk_man = m_spk_man.get()) {
         count += spk_man->GetKeyPoolSize();
     }
     return count;
 }
 
 bool CWallet::TopUpKeyPool(unsigned int kpSize) {
     LOCK(cs_wallet);
     bool res = true;
     if (auto spk_man = m_spk_man.get()) {
         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 = m_spk_man.get();
     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();
     if (auto spk_man = m_spk_man.get()) {
         oldestKey = spk_man->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->GetLegacyScriptPubKeyMan();
     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)) {
             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;
         }
 
         if (auto spk_man = walletInstance->m_spk_man.get()) {
             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);
             if (auto spk_man = walletInstance->m_spk_man.get()) {
                 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)) {
         if (walletInstance->m_spk_man) {
             if (walletInstance->m_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)
         Optional<int64_t> time_first_key;
         if (auto spk_man = walletInstance->m_spk_man.get()) {
             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);
         if (m_spk_man) {
             if (!m_spk_man->CheckDecryptionKey(vMasterKeyIn, accept_no_keys)) {
                 return false;
             }
         }
         vMasterKey = vMasterKeyIn;
     }
     NotifyStatusChanged(this);
     return true;
 }
 
 ScriptPubKeyMan *CWallet::GetScriptPubKeyMan(const CScript &script) const {
     return m_spk_man.get();
 }
 
 const SigningProvider *
 CWallet::GetSigningProvider(const CScript &script) const {
     return m_spk_man.get();
 }
 
 const SigningProvider *
 CWallet::GetSigningProvider(const CScript &script,
                             SignatureData &sigdata) const {
     return m_spk_man.get();
 }
 
 LegacyScriptPubKeyMan *CWallet::GetLegacyScriptPubKeyMan() const {
     return m_spk_man.get();
 }
 
 LegacyScriptPubKeyMan *CWallet::GetOrCreateLegacyScriptPubKeyMan() {
     SetupLegacyScriptPubKeyMan();
     return GetLegacyScriptPubKeyMan();
 }
 
 void CWallet::SetupLegacyScriptPubKeyMan() {
     if (!m_spk_man) {
         m_spk_man = std::make_unique<LegacyScriptPubKeyMan>(*this);
     }
 }
 
 const CKeyingMaterial &CWallet::GetEncryptionKey() const {
     return vMasterKey;
 }
 
 bool CWallet::HasEncryptionKeys() const {
     return !mapMasterKeys.empty();
 }