text: // Copyright (c) 2009-2010 Satoshi Nakamoto
  // Copyright (c) 2009-2012 The Bitcoin developers
  // Copyright (c) 2011-2012 Litecoin Developers
  // Distributed under the MIT/X11 software license, see the accompanying
  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
  #ifndef BITCOIN_WALLET_H
  #define BITCOIN_WALLET_H
  
  #include "amount.h"
  #include "primitives/block.h"
  #include "primitives/transaction.h"
  #include "crypter.h"
  #include "key.h"
  #include "keystore.h"
  #include "main.h"
  #include "wallet_ismine.h"
  #include "ui_interface.h"
  #include "walletdb.h"
  
  #include <algorithm>
  #include <map>
  #include <set>
  #include <stdexcept>
  #include <stdint.h>
  #include <string>
  #include <utility>
  #include <vector>
  
  // Settings
  extern CFeeRate payTxFee;
  extern CAmount maxTxFee;
  extern unsigned int nTxConfirmTarget;
  extern bool bSpendZeroConfChange;
  extern bool fSendFreeTransactions;
  extern bool fPayAtLeastCustomFee;
  
  // -paytxfee default
  static const CAmount DEFAULT_TRANSACTION_FEE = 0;
  // -paytxfee will warn if called with a higher fee than this amount (in satoshis) per KB
  static const CAmount nHighTransactionFeeWarning = 1000 * COIN;
  //! -maxtxfee default
  static const CAmount DEFAULT_TRANSACTION_MAXFEE = 1000 * COIN;
  //! -maxtxfee will warn if called with a higher fee than this amount (in satoshis)
  static const CAmount nHighTransactionMaxFeeWarning = 1000000 * nHighTransactionFeeWarning;
  // Largest (in bytes) free transaction we're willing to create
  static const unsigned int MAX_FREE_TRANSACTION_CREATE_SIZE = 1000;
  
  class CAccountingEntry;
  class CCoinControl;
  class COutput;
  class CReserveKey;
  class CScript;
  class CWalletTx;
  
  /** (client) version numbers for particular wallet features */
  enum WalletFeature
  {
      FEATURE_BASE = 60000, // the earliest version new wallets supports (only useful for getinfo's clientversion output)
  
      FEATURE_WALLETCRYPT = 40000, // wallet encryption
      FEATURE_COMPRPUBKEY = 60000, // compressed public keys
  
      FEATURE_LATEST = 60000
  };
  
  
  /** A key pool entry */
  class CKeyPool
  {
  public:
      int64_t nTime;
      CPubKey vchPubKey;
  
      CKeyPool();
      CKeyPool(const CPubKey& vchPubKeyIn);
  
      ADD_SERIALIZE_METHODS;
  
      template <typename Stream, typename Operation>
      inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
          if (!(nType & SER_GETHASH))
              READWRITE(nVersion);
          READWRITE(nTime);
          READWRITE(vchPubKey);
      }
  };
  
  /** Address book data */
  class CAddressBookData
  {
  public:
      std::string name;
      std::string purpose;
  
      CAddressBookData()
      {
          purpose = "unknown";
      }
      
      typedef std::map<std::string, std::string> StringMap;
      StringMap destdata;
  };
  
  typedef std::map<std::string, std::string> mapValue_t;
  
  
  static void ReadOrderPos(int64_t& nOrderPos, mapValue_t& mapValue)
  {
      if (!mapValue.count("n"))
      {
          nOrderPos = -1; // TODO: calculate elsewhere
          return;
      }
      nOrderPos = atoi64(mapValue["n"].c_str());
  }
  
  
  static void WriteOrderPos(const int64_t& nOrderPos, mapValue_t& mapValue)
  {
      if (nOrderPos == -1)
          return;
      mapValue["n"] = i64tostr(nOrderPos);
  }
  
  struct COutputEntry
  {
      CTxDestination destination;
      CAmount amount;
      int vout;
  };
  
  /** A transaction with a merkle branch linking it to the block chain. */
  class CMerkleTx : public CTransaction
  {
  private:
      int GetDepthInMainChainINTERNAL(const CBlockIndex* &pindexRet) const;
  
  public:
      uint256 hashBlock;
      std::vector<uint256> vMerkleBranch;
      int nIndex;
  
      // memory only
      mutable bool fMerkleVerified;
  
      CMerkleTx()
      {
          Init();
      }
      
      CMerkleTx(const CTransaction& txIn) : CTransaction(txIn)
      {
          Init();
      }
  
      void Init()
      {
          hashBlock = uint256();
          nIndex = -1;
          fMerkleVerified = false;
      }
  
      ADD_SERIALIZE_METHODS;
  
      template <typename Stream, typename Operation>
      inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
          READWRITE(*(CTransaction*)this);
          nVersion = this->nVersion;
          READWRITE(hashBlock);
          READWRITE(vMerkleBranch);
          READWRITE(nIndex);
      }
  
      int SetMerkleBranch(const CBlock& block);
  
  
      /**
       * Return depth of transaction in blockchain:
       * -1  : not in blockchain, and not in memory pool (conflicted transaction)
       *  0  : in memory pool, waiting to be included in a block
       * >=1 : this many blocks deep in the main chain
       */
      int GetDepthInMainChain(const CBlockIndex* &pindexRet) const;
      int GetDepthInMainChain() const { const CBlockIndex *pindexRet; return GetDepthInMainChain(pindexRet); }
      bool IsInMainChain() const { const CBlockIndex *pindexRet; return GetDepthInMainChainINTERNAL(pindexRet) > 0; }
      int GetBlocksToMaturity() const;
      bool AcceptToMemoryPool(bool fLimitFree=true, bool fRejectAbsurdFee=true);
  };
  
  /** 
   * A transaction with a bunch of additional info that only the owner cares about.
   * It includes any unrecorded transactions needed to link it back to the block chain.
   */
  class CWalletTx : public CMerkleTx
  {
  private:
      const CWallet* pwallet;
  
  public:
      mapValue_t mapValue;
      std::vector<std::pair<std::string, std::string> > vOrderForm;
      unsigned int fTimeReceivedIsTxTime;
      unsigned int nTimeReceived; //! time received by this node
      unsigned int nTimeSmart;
      char fFromMe;
      std::string strFromAccount;
      int64_t nOrderPos; //! position in ordered transaction list;
  
      // memory only
      mutable bool fDebitCached;
      mutable bool fCreditCached;
      mutable bool fImmatureCreditCached;
      mutable bool fAvailableCreditCached;
      mutable bool fWatchDebitCached;
      mutable bool fWatchCreditCached;
      mutable bool fImmatureWatchCreditCached;
      mutable bool fAvailableWatchCreditCached;
      mutable bool fChangeCached;
      mutable CAmount nDebitCached;
      mutable CAmount nCreditCached;
      mutable CAmount nImmatureCreditCached;
      mutable CAmount nAvailableCreditCached;
      mutable CAmount nWatchDebitCached;
      mutable CAmount nWatchCreditCached;
      mutable CAmount nImmatureWatchCreditCached;
      mutable CAmount nAvailableWatchCreditCached;
      mutable CAmount nChangeCached;
  
      CWalletTx()
      {
          Init(NULL);
      }
      CWalletTx(const CWallet* pwalletIn)
      {
          Init(pwalletIn);
      }
          
      CWalletTx(const CWallet* pwalletIn, const CMerkleTx& txIn) : CMerkleTx(txIn)
      {
          Init(pwalletIn);
      }
      
      CWalletTx(const CWallet* pwalletIn, const CTransaction& txIn) : CMerkleTx(txIn)  
      {
          Init(pwalletIn);
      }  
      
      void Init(const CWallet* pwalletIn)
      {
          pwallet = pwalletIn;
          mapValue.clear();
          vOrderForm.clear();
          fTimeReceivedIsTxTime = false;
          nTimeReceived = 0;
          nTimeSmart = 0;
          fFromMe = false;
          strFromAccount.clear();
          fDebitCached = false;
          fCreditCached = false;
          fImmatureCreditCached = false;
          fAvailableCreditCached = false;
          fWatchDebitCached = false;
          fWatchCreditCached = false;
          fImmatureWatchCreditCached = false;
          fAvailableWatchCreditCached = false;
          fChangeCached = false;
          nDebitCached = 0;
          nCreditCached = 0;
          nImmatureCreditCached = 0;
          nAvailableCreditCached = 0;
          nWatchDebitCached = 0;
          nWatchCreditCached = 0;
          nAvailableWatchCreditCached = 0;
          nImmatureWatchCreditCached = 0;
          nChangeCached = 0;
          nOrderPos = -1;
      }
  
      ADD_SERIALIZE_METHODS;
      
      template <typename Stream, typename Operation>
      inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
          if (ser_action.ForRead())
              Init(NULL);
          char fSpent = false;
  
          if (!ser_action.ForRead())
          {
              mapValue["fromaccount"] = strFromAccount;
  
              WriteOrderPos(nOrderPos, mapValue);
      
              if (nTimeSmart)
                  mapValue["timesmart"] = strprintf("%u", nTimeSmart);
          }
      
          READWRITE(*(CMerkleTx*)this);
          std::vector<CMerkleTx> vUnused; //! Used to be vtxPrev
          READWRITE(vUnused);
          READWRITE(mapValue);
          READWRITE(vOrderForm);
          READWRITE(fTimeReceivedIsTxTime);
          READWRITE(nTimeReceived);
          READWRITE(fFromMe);
          READWRITE(fSpent);
      
          if (ser_action.ForRead())
          {
              strFromAccount = mapValue["fromaccount"];
  
              ReadOrderPos(nOrderPos, mapValue);
  
              nTimeSmart = mapValue.count("timesmart") ? (unsigned int)atoi64(mapValue["timesmart"]) : 0;
          }
      
          mapValue.erase("fromaccount");
          mapValue.erase("version");
          mapValue.erase("spent");
          mapValue.erase("n");
          mapValue.erase("timesmart");
      }
      
      //! make sure balances are recalculated
      void MarkDirty()
      {
          fCreditCached = false;
          fAvailableCreditCached = false;
          fWatchDebitCached = false;
          fWatchCreditCached = false;
          fAvailableWatchCreditCached = false;
          fImmatureWatchCreditCached = false;
          fDebitCached = false;
          fChangeCached = false;
      }
  
      void BindWallet(CWallet *pwalletIn)
      {
          pwallet = pwalletIn;
          MarkDirty();
      }
  
      //! filter decides which addresses will count towards the debit
      CAmount GetDebit(const isminefilter& filter) const;
      CAmount GetCredit(const isminefilter& filter) const;
      CAmount GetImmatureCredit(bool fUseCache=true) const;
      CAmount GetAvailableCredit(bool fUseCache=true) const;
      CAmount GetImmatureWatchOnlyCredit(const bool& fUseCache=true) const;
      CAmount GetAvailableWatchOnlyCredit(const bool& fUseCache=true) const;
      CAmount GetChange() const;
  
      void GetAmounts(std::list<COutputEntry>& listReceived,
                      std::list<COutputEntry>& listSent, CAmount& nFee, std::string& strSentAccount, const isminefilter& filter) const;
  
      void GetAccountAmounts(const std::string& strAccount, CAmount& nReceived,
                             CAmount& nSent, CAmount& nFee, const isminefilter& filter) const;
  
      bool IsFromMe(const isminefilter& filter) const
      {
          return (GetDebit(filter) > 0);
      }
  
      bool IsTrusted() const;
  
      bool WriteToDisk(CWalletDB *pwalletdb);
  
      int64_t GetTxTime() const;
      int GetRequestCount() const;
  
      void RelayWalletTransaction();
  
      std::set<uint256> GetConflicts() const;
  };
  
  
  
  
  class COutput
  {
  public:
      const CWalletTx *tx;
      int i;
      int nDepth;
      bool fSpendable;
  
      COutput(const CWalletTx *txIn, int iIn, int nDepthIn, bool fSpendableIn)
      {
          tx = txIn; i = iIn; nDepth = nDepthIn; fSpendable = fSpendableIn;
      }
  
      std::string ToString() const;
  };
  
  
  
  
  /** Private key that includes an expiration date in case it never gets used. */
  class CWalletKey
  {
  public:
      CPrivKey vchPrivKey;
      int64_t nTimeCreated;
      int64_t nTimeExpires;
      std::string strComment;
      //! todo: add something to note what created it (user, getnewaddress, change)
      //!   maybe should have a map<string, string> property map
  
      CWalletKey(int64_t nExpires=0);
  
      ADD_SERIALIZE_METHODS;
  
      template <typename Stream, typename Operation>
      inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
          if (!(nType & SER_GETHASH))
              READWRITE(nVersion);
          READWRITE(vchPrivKey);
          READWRITE(nTimeCreated);
          READWRITE(nTimeExpires);
          READWRITE(LIMITED_STRING(strComment, 65536));
      }
  };
  
  
  
  /** 
   * A CWallet is an extension of a keystore, which also maintains a set of transactions and balances,
   * and provides the ability to create new transactions.
   */
  class CWallet : public CCryptoKeyStore, public CValidationInterface
  {
  private:
      bool SelectCoins(const CAmount& nTargetValue, std::set<std::pair<const CWalletTx*,unsigned int> >& setCoinsRet, CAmount& nValueRet, const CCoinControl *coinControl = NULL) const;
  
      CWalletDB *pwalletdbEncryption;
  
      //! the current wallet version: clients below this version are not able to load the wallet
      int nWalletVersion;
  
      //! the maximum wallet format version: memory-only variable that specifies to what version this wallet may be upgraded
      int nWalletMaxVersion;
  
      int64_t nNextResend;
      int64_t nLastResend;
  
      /**
       * Used to keep track of spent outpoints, and
       * detect and report conflicts (double-spends or
       * mutated transactions where the mutant gets mined).
       */
      typedef std::multimap<COutPoint, uint256> TxSpends;
      TxSpends mapTxSpends;
      void AddToSpends(const COutPoint& outpoint, const uint256& wtxid);
      void AddToSpends(const uint256& wtxid);
  
      void SyncMetaData(std::pair<TxSpends::iterator, TxSpends::iterator>);
  
  public:
      /*
       * Main wallet lock.
       * This lock protects all the fields added by CWallet
       *   except for:
       *      fFileBacked (immutable after instantiation)
       *      strWalletFile (immutable after instantiation)
       */
      mutable CCriticalSection cs_wallet;
  
      bool fFileBacked;
      std::string strWalletFile;
  
      std::set<int64_t> setKeyPool;
      std::map<CKeyID, CKeyMetadata> mapKeyMetadata;
  
      typedef std::map<unsigned int, CMasterKey> MasterKeyMap;
      MasterKeyMap mapMasterKeys;
      unsigned int nMasterKeyMaxID;
  
      CWallet()
      {
          SetNull();
      }
  
      CWallet(std::string strWalletFileIn)
      {
          SetNull();
  
          strWalletFile = strWalletFileIn;
          fFileBacked = true;
      }
  
      ~CWallet()
      {
          delete pwalletdbEncryption;
          pwalletdbEncryption = NULL;
      }
  
      void SetNull()
      {
          nWalletVersion = FEATURE_BASE;
          nWalletMaxVersion = FEATURE_BASE;
          fFileBacked = false;
          nMasterKeyMaxID = 0;
          pwalletdbEncryption = NULL;
          nOrderPosNext = 0;
          nNextResend = 0;
          nLastResend = 0;
          nTimeFirstKey = 0;
      }
  
      std::map<uint256, CWalletTx> mapWallet;
  
      int64_t nOrderPosNext;
      std::map<uint256, int> mapRequestCount;
  
      std::map<CTxDestination, CAddressBookData> mapAddressBook;
  
      CPubKey vchDefaultKey;
  
      std::set<COutPoint> setLockedCoins;
  
      int64_t nTimeFirstKey;
  
      const CWalletTx* GetWalletTx(const uint256& hash) const;
  
      //! check whether we are allowed to upgrade (or already support) to the named feature
      bool CanSupportFeature(enum WalletFeature wf) { AssertLockHeld(cs_wallet); return nWalletMaxVersion >= wf; }
  
      void AvailableCoins(std::vector<COutput>& vCoins, bool fOnlyConfirmed=true, const CCoinControl *coinControl = NULL) const;
      bool SelectCoinsMinConf(const CAmount& nTargetValue, int nConfMine, int nConfTheirs, std::vector<COutput> vCoins, std::set<std::pair<const CWalletTx*,unsigned int> >& setCoinsRet, CAmount& nValueRet) const;
  
      bool IsSpent(const uint256& hash, unsigned int n) const;
  
      bool IsLockedCoin(uint256 hash, unsigned int n) const;
      void LockCoin(COutPoint& output);
      void UnlockCoin(COutPoint& output);
      void UnlockAllCoins();
      void ListLockedCoins(std::vector<COutPoint>& vOutpts);
  
      // keystore implementation
      // Generate a new key
      CPubKey GenerateNewKey();
      // Adds a key to the store, and saves it to disk.
      bool AddKeyPubKey(const CKey& key, const CPubKey &pubkey);
      // Adds a key to the store, without saving it to disk (used by LoadWallet)
      bool LoadKey(const CKey& key, const CPubKey &pubkey) { return CCryptoKeyStore::AddKeyPubKey(key, pubkey); }
      // Load metadata (used by LoadWallet)
      bool LoadKeyMetadata(const CPubKey &pubkey, const CKeyMetadata &metadata);
  
      bool LoadMinVersion(int nVersion) { AssertLockHeld(cs_wallet); nWalletVersion = nVersion; nWalletMaxVersion = std::max(nWalletMaxVersion, nVersion); return true; }
  
      // Adds an encrypted key to the store, and saves it to disk.
      bool AddCryptedKey(const CPubKey &vchPubKey, const std::vector<unsigned char> &vchCryptedSecret);
      // Adds an encrypted key to the store, without saving it to disk (used by LoadWallet)
      bool LoadCryptedKey(const CPubKey &vchPubKey, const std::vector<unsigned char> &vchCryptedSecret);
      bool AddCScript(const CScript& redeemScript);
      bool LoadCScript(const CScript& redeemScript);
  
      /// Adds a destination data tuple to the store, and saves it to disk
      bool AddDestData(const CTxDestination &dest, const std::string &key, const std::string &value);
      /// Erases a destination data tuple in the store and on disk
      bool EraseDestData(const CTxDestination &dest, const std::string &key);
      /// Adds a destination data tuple to the store, without saving it to disk
      bool LoadDestData(const CTxDestination &dest, const std::string &key, const std::string &value);
      /// Look up a destination data tuple in the store, return true if found false otherwise
      bool GetDestData(const CTxDestination &dest, const std::string &key, std::string *value) const;
      
      // Adds a watch-only address to the store, and saves it to disk.
      bool AddWatchOnly(const CScript &dest);
      bool RemoveWatchOnly(const CScript &dest);
      // Adds a watch-only address to the store, without saving it to disk (used by LoadWallet)
      bool LoadWatchOnly(const CScript &dest);
  
      bool Unlock(const SecureString& strWalletPassphrase);
      bool ChangeWalletPassphrase(const SecureString& strOldWalletPassphrase, const SecureString& strNewWalletPassphrase);
      bool EncryptWallet(const SecureString& strWalletPassphrase);
      
      void GetKeyBirthTimes(std::map<CKeyID, int64_t> &mapKeyBirth) const;
      
      /** Increment the next transaction order id
          @return next transaction order id
       */
      int64_t IncOrderPosNext(CWalletDB *pwalletdb = NULL);
      
      typedef std::pair<CWalletTx*, CAccountingEntry*> TxPair;
      typedef std::multimap<int64_t, TxPair > TxItems;
  
      /** Get the wallet's activity log
          @return multimap of ordered transactions and accounting entries
          @warning Returned pointers are *only* valid within the scope of passed acentries
       */
      TxItems OrderedTxItems(std::list<CAccountingEntry>& acentries, std::string strAccount = "");
  
      void MarkDirty();
      bool AddToWallet(const CWalletTx& wtxIn, bool fFromLoadWallet, CWalletDB* pwalletdb);
      void SyncTransaction(const CTransaction& tx, const CBlock* pblock);
      bool AddToWalletIfInvolvingMe(const CTransaction& tx, const CBlock* pblock, bool fUpdate);
      void EraseFromWallet(const uint256 &hash);
      int ScanForWalletTransactions(CBlockIndex* pindexStart, bool fUpdate = false);
      void ReacceptWalletTransactions();
      void ResendWalletTransactions();
      CAmount GetBalance() const;
      CAmount GetUnconfirmedBalance() const;
      CAmount GetImmatureBalance() const;
      
      CAmount GetWatchOnlyBalance() const;
      CAmount GetUnconfirmedWatchOnlyBalance() const;
      CAmount GetImmatureWatchOnlyBalance() const;
      bool CreateTransaction(const std::vector<std::pair<CScript, CAmount> >& vecSend,
                             CWalletTx& wtxNew, CReserveKey& reservekey, CAmount& nFeeRet, std::string& strFailReason, const CCoinControl *coinControl = NULL);
      bool CreateTransaction(CScript scriptPubKey, const CAmount& nValue,
                             CWalletTx& wtxNew, CReserveKey& reservekey, CAmount& nFeeRet, std::string& strFailReason, const CCoinControl *coinControl = NULL);
      bool CommitTransaction(CWalletTx& wtxNew, CReserveKey& reservekey);
  
      static CFeeRate minTxFee;
      static CAmount GetMinimumFee(unsigned int nTxBytes, unsigned int nConfirmTarget, const CTxMemPool& pool);
  
      bool NewKeyPool();
      bool TopUpKeyPool(unsigned int kpSize = 0);
      void ReserveKeyFromKeyPool(int64_t& nIndex, CKeyPool& keypool);
      void KeepKey(int64_t nIndex);
      void ReturnKey(int64_t nIndex);
      bool GetKeyFromPool(CPubKey &key);
      int64_t GetOldestKeyPoolTime();
      void GetAllReserveKeys(std::set<CKeyID>& setAddress) const;
  
      std::set< std::set<CTxDestination> > GetAddressGroupings();
      std::map<CTxDestination, CAmount> GetAddressBalances();
              
      std::set<CTxDestination> GetAccountAddresses(std::string strAccount) const;
          
      isminetype IsMine(const CTxIn& txin) const;
      CAmount GetDebit(const CTxIn& txin, const isminefilter& filter) const;
      isminetype IsMine(const CTxOut& txout) const
      {
          return ::IsMine(*this, txout.scriptPubKey);
      }
      CAmount GetCredit(const CTxOut& txout, const isminefilter& filter) const
      {
          if (!MoneyRange(txout.nValue))
              throw std::runtime_error("CWallet::GetCredit(): value out of range");
          return ((IsMine(txout) & filter) ? txout.nValue : 0);
      }
      bool IsChange(const CTxOut& txout) const;
      CAmount GetChange(const CTxOut& txout) const
      {
          if (!MoneyRange(txout.nValue))
              throw std::runtime_error("CWallet::GetChange(): value out of range");
          return (IsChange(txout) ? txout.nValue : 0);
      }
  
      bool IsMine(const CTransaction& tx) const
      {
          BOOST_FOREACH(const CTxOut& txout, tx.vout)
              if (IsMine(txout))
                  return true;
          return false;
      }
      /** should probably be renamed to IsRelevantToMe */
      bool IsFromMe(const CTransaction& tx) const
      {
          return (GetDebit(tx, ISMINE_ALL) > 0);
      }
  
      CAmount GetDebit(const CTransaction& tx, const isminefilter& filter) const
      {
          CAmount nDebit = 0;
          BOOST_FOREACH(const CTxIn& txin, tx.vin)
          {
              nDebit += GetDebit(txin, filter);
              if (!MoneyRange(nDebit))
                  throw std::runtime_error("CWallet::GetDebit(): value out of range");
          }
          return nDebit;
      }    
      CAmount GetCredit(const CTransaction& tx, const isminefilter& filter) const
      {
          CAmount nCredit = 0;
          BOOST_FOREACH(const CTxOut& txout, tx.vout)
          {
              nCredit += GetCredit(txout, filter);
              if (!MoneyRange(nCredit))
                  throw std::runtime_error("CWallet::GetCredit(): value out of range");
          }
          return nCredit;
      }
  
      CAmount GetChange(const CTransaction& tx) const
      {
          CAmount nChange = 0;
          BOOST_FOREACH(const CTxOut& txout, tx.vout)
          {
              nChange += GetChange(txout);
              if (!MoneyRange(nChange))
                  throw std::runtime_error("CWallet::GetChange(): value out of range");
          }
          return nChange;
      }
      void SetBestChain(const CBlockLocator& loc);
  
      DBErrors LoadWallet(bool& fFirstRunRet);
      DBErrors ZapWalletTx(std::vector<CWalletTx>& vWtx);
  
      bool SetAddressBook(const CTxDestination& address, const std::string& strName, const std::string& purpose);
  
      bool DelAddressBook(const CTxDestination& address);
  
      void UpdatedTransaction(const uint256 &hashTx);
  
      void Inventory(const uint256 &hash)
      {
          {
              LOCK(cs_wallet);
              std::map<uint256, int>::iterator mi = mapRequestCount.find(hash);
              if (mi != mapRequestCount.end())
                  (*mi).second++;
          }
      }
  
      unsigned int GetKeyPoolSize()
      {
          AssertLockHeld(cs_wallet); // setKeyPool
          return setKeyPool.size();
      }
  
      bool SetDefaultKey(const CPubKey &vchPubKey);
  
      //! signify that a particular wallet feature is now used. this may change nWalletVersion and nWalletMaxVersion if those are lower
      bool SetMinVersion(enum WalletFeature, CWalletDB* pwalletdbIn = NULL, bool fExplicit = false);
  
      //! change which version we're allowed to upgrade to (note that this does not immediately imply upgrading to that format)
      bool SetMaxVersion(int nVersion);
  
      //! get the current wallet format (the oldest client version guaranteed to understand this wallet)
      int GetVersion() { LOCK(cs_wallet); return nWalletVersion; }
      
      //! Get wallet transactions that conflict with given transaction (spend same outputs)
      std::set<uint256> GetConflicts(const uint256& txid) const;
      
      /** 
       * Address book entry changed.
       * @note called with lock cs_wallet held.
       */
      boost::signals2::signal<void (CWallet *wallet, const CTxDestination
              &address, const std::string &label, bool isMine,
              const std::string &purpose,
              ChangeType status)> NotifyAddressBookChanged;
  
      /** 
       * Wallet transaction added, removed or updated.
       * @note called with lock cs_wallet held.
       */
      boost::signals2::signal<void (CWallet *wallet, const uint256 &hashTx,
              ChangeType status)> NotifyTransactionChanged;
  
      /** Show progress e.g. for rescan */
      boost::signals2::signal<void (const std::string &title, int nProgress)> ShowProgress;
  
      /** Watch-only address added */
      boost::signals2::signal<void (bool fHaveWatchOnly)> NotifyWatchonlyChanged;
  };
  
  /** A key allocated from the key pool. */
  class CReserveKey
  {
  protected:
      CWallet* pwallet;
      int64_t nIndex;
      CPubKey vchPubKey;
  public:
      CReserveKey(CWallet* pwalletIn)
      {
          nIndex = -1;
          pwallet = pwalletIn;
      }
  
      ~CReserveKey()
      {
          ReturnKey();
      }
  
      void ReturnKey();
      bool GetReservedKey(CPubKey &pubkey);
      void KeepKey();
  };
  
  
  /** Account information.
   * Stored in wallet with key "acc"+string account name.
   */
  class CAccount
  {
  public:
      CPubKey vchPubKey;
  
      CAccount()
      {
          SetNull();
      }
  
      void SetNull()
      {
          vchPubKey = CPubKey();
      }
  
      ADD_SERIALIZE_METHODS;
  
      template <typename Stream, typename Operation>
      inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
          if (!(nType & SER_GETHASH))
              READWRITE(nVersion);
          READWRITE(vchPubKey);
      }
  };
  
  
  
  /** Internal transfers.
   * Database key is acentry<account><counter>.
   */
  class CAccountingEntry
  {
  public:
      std::string strAccount;
      CAmount nCreditDebit;
      int64_t nTime;
      std::string strOtherAccount;
      std::string strComment;
      mapValue_t mapValue;
      int64_t nOrderPos;  // position in ordered transaction list
      uint64_t nEntryNo;
  
      CAccountingEntry()
      {
          SetNull();
      }
  
      void SetNull()
      {
          nCreditDebit = 0;
          nTime = 0;
          strAccount.clear();
          strOtherAccount.clear();
          strComment.clear();
          nOrderPos = -1;
          nEntryNo = 0;
      }
  
      ADD_SERIALIZE_METHODS;
  
      template <typename Stream, typename Operation>
      inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
          if (!(nType & SER_GETHASH))
              READWRITE(nVersion);
          // Note: strAccount is serialized as part of the key, not here.
          READWRITE(nCreditDebit);
          READWRITE(nTime);
          READWRITE(LIMITED_STRING(strOtherAccount, 65536));
          
          if (!ser_action.ForRead())
          {
              WriteOrderPos(nOrderPos, mapValue);
  
              if (!(mapValue.empty() && _ssExtra.empty()))
              {
                  CDataStream ss(nType, nVersion);
                  ss.insert(ss.begin(), '\0');
                  ss << mapValue;
                  ss.insert(ss.end(), _ssExtra.begin(), _ssExtra.end());
                  strComment.append(ss.str());
              }
          }
  
          READWRITE(LIMITED_STRING(strComment, 65536));
          
          size_t nSepPos = strComment.find("\0", 0, 1);
          if (ser_action.ForRead())
          {
              mapValue.clear();
              if (std::string::npos != nSepPos)
              {
                  CDataStream ss(std::vector<char>(strComment.begin() + nSepPos + 1, strComment.end()), nType, nVersion);
                  ss >> mapValue;
                  _ssExtra = std::vector<char>(ss.begin(), ss.end());
              }
              ReadOrderPos(nOrderPos, mapValue);
          }
          if (std::string::npos != nSepPos)
              strComment.erase(nSepPos);
  
          mapValue.erase("n");
      }
  
  private:
      std::vector<char> _ssExtra;
  };
  
  #endif