text: // Copyright (c) 2011-2015 The Bitcoin Core developers
  // Copyright (c) 2015-2017 The Bitcoin Unlimited developers
  // Distributed under the MIT software license, see the accompanying
  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
  
  #ifndef BITCOIN_QT_WALLETMODEL_H
  #define BITCOIN_QT_WALLETMODEL_H
  
  #include "paymentrequestplus.h"
  #include "walletmodeltransaction.h"
  
  #include "support/allocators/secure.h"
  
  #include <map>
  #include <vector>
  
  #include <QObject>
  
  class AddressTableModel;
  class OptionsModel;
  class PlatformStyle;
  class RecentRequestsTableModel;
  class TransactionTableModel;
  class WalletModelTransaction;
  
  class CCoinControl;
  class CKeyID;
  class COutPoint;
  class COutput;
  class CPubKey;
  class CWallet;
  class uint256;
  
  QT_BEGIN_NAMESPACE
  class QTimer;
  QT_END_NAMESPACE
  
  class SendCoinsRecipient
  {
  public:
      explicit SendCoinsRecipient()
          : amount(0), fSubtractFeeFromAmount(false), nVersion(SendCoinsRecipient::CURRENT_VERSION)
      {
      }
      explicit SendCoinsRecipient(const QString &addr,
          const QString &label,
          const CAmount &amount,
          const QString &message,
          const QString &freezeLockTime,
          const QString &labelPublic)
          : address(addr), label(label), labelPublic(labelPublic), amount(amount), message(message),
            freezeLockTime(freezeLockTime), fSubtractFeeFromAmount(false), nVersion(SendCoinsRecipient::CURRENT_VERSION)
      {
      }
  
      // If from an unauthenticated payment request, this is used for storing
      // the addresses, e.g. address-A<br />address-B<br />address-C.
      // Info: As we don't need to process addresses in here when using
      // payment requests, we can abuse it for displaying an address list.
      // Todo: This is a hack, should be replaced with a cleaner solution!
      QString address;
      QString label;
      QString labelPublic;
      CAmount amount;
      // If from a payment request, this is used for storing the memo
      QString message;
      // Freeze Lock Time
      QString freezeLockTime;
  
      // If from a payment request, paymentRequest.IsInitialized() will be true
      PaymentRequestPlus paymentRequest;
      // Empty if no authentication or invalid signature/cert/etc.
      QString authenticatedMerchant;
  
      bool fSubtractFeeFromAmount; // memory only
  
      static const int CURRENT_VERSION = 2;
      int nVersion;
  
      ADD_SERIALIZE_METHODS;
  
      template <typename Stream, typename Operation>
      inline void SerializationOp(Stream &s, Operation ser_action)
      {
          std::string sAddress = address.toStdString();
          std::string sLabel = label.toStdString();
          std::string sMessage = message.toStdString();
          std::string sFreezeLockTime = freezeLockTime.toStdString();
          std::string slabelPublic = labelPublic.toStdString();
          std::string sPaymentRequest;
          if (!ser_action.ForRead() && paymentRequest.IsInitialized())
              paymentRequest.SerializeToString(&sPaymentRequest);
          std::string sAuthenticatedMerchant = authenticatedMerchant.toStdString();
  
          READWRITE(this->nVersion);
          nVersion = this->nVersion;
          READWRITE(sAddress);
          READWRITE(sLabel);
          READWRITE(amount);
          READWRITE(sMessage);
          READWRITE(sPaymentRequest);
          READWRITE(sAuthenticatedMerchant);
          if (nVersion >= 2)
              READWRITE(sFreezeLockTime);
  
          if (ser_action.ForRead())
          {
              address = QString::fromStdString(sAddress);
              label = QString::fromStdString(sLabel);
              message = QString::fromStdString(sMessage);
              freezeLockTime = QString::fromStdString(sFreezeLockTime);
              labelPublic = QString::fromStdString(slabelPublic);
              if (!sPaymentRequest.empty())
                  paymentRequest.parse(QByteArray::fromRawData(sPaymentRequest.data(), sPaymentRequest.size()));
              authenticatedMerchant = QString::fromStdString(sAuthenticatedMerchant);
          }
      }
  };
  
  /** Interface to Bitcoin wallet from Qt view code. */
  class WalletModel : public QObject
  {
      Q_OBJECT
  
  public:
      explicit WalletModel(const PlatformStyle *platformStyle,
          CWallet *wallet,
          OptionsModel *optionsModel,
          QObject *parent = 0);
      ~WalletModel();
  
      enum StatusCode // Returned by sendCoins
      {
          OK,
          InvalidAmount,
          InvalidAddress,
          AmountExceedsBalance,
          AmountWithFeeExceedsBalance,
          DuplicateAddress,
          TransactionCreationFailed, // Error returned when wallet is still locked
          TransactionCommitFailed,
          AbsurdFee,
          PaymentRequestExpired
      };
  
      enum EncryptionStatus
      {
          Unencrypted, // !wallet->IsCrypted()
          Locked, // wallet->IsCrypted() && wallet->IsLocked()
          Unlocked // wallet->IsCrypted() && !wallet->IsLocked()
      };
  
      OptionsModel *getOptionsModel();
      AddressTableModel *getAddressTableModel();
      TransactionTableModel *getTransactionTableModel();
      RecentRequestsTableModel *getRecentRequestsTableModel();
  
      CAmount getBalance(const CCoinControl *coinControl = NULL) const;
      CAmount getUnconfirmedBalance() const;
      CAmount getImmatureBalance() const;
      bool haveWatchOnly() const;
      CAmount getWatchBalance() const;
      CAmount getWatchUnconfirmedBalance() const;
      CAmount getWatchImmatureBalance() const;
      EncryptionStatus getEncryptionStatus() const;
  
      // Check address for validity
      bool validateAddress(const QString &address);
  
      // Return status record for SendCoins, contains error id + information
      struct SendCoinsReturn
      {
          SendCoinsReturn(StatusCode status = OK) : status(status) {}
          StatusCode status;
      };
  
      // prepare transaction for getting txfee before sending coins
      SendCoinsReturn prepareTransaction(WalletModelTransaction &transaction, const CCoinControl *coinControl = NULL);
  
      // Send coins to a list of recipients
      SendCoinsReturn sendCoins(WalletModelTransaction &transaction);
  
      // Wallet encryption
      bool setWalletEncrypted(bool encrypted, const SecureString &passphrase);
      // Passphrase only needed when unlocking
      bool setWalletLocked(bool locked, const SecureString &passPhrase = SecureString());
      bool changePassphrase(const SecureString &oldPass, const SecureString &newPass);
      // Wallet backup
      bool backupWallet(const QString &filename);
  
      // RAI object for unlocking wallet, returned by requestUnlock()
      class UnlockContext
      {
      public:
          UnlockContext(WalletModel *wallet, bool valid, bool relock);
          ~UnlockContext();
  
          bool isValid() const { return valid; }
          // Copy operator and constructor transfer the context
          UnlockContext(const UnlockContext &obj) { CopyFrom(obj); }
          UnlockContext &operator=(const UnlockContext &rhs)
          {
              CopyFrom(rhs);
              return *this;
          }
  
      private:
          WalletModel *wallet;
          bool valid;
          mutable bool relock; // mutable, as it can be set to false by copying
  
          void CopyFrom(const UnlockContext &rhs);
      };
  
      UnlockContext requestUnlock();
  
      bool getPubKey(const CKeyID &address, CPubKey &vchPubKeyOut) const;
      bool IsSpendable(const CTxDestination &dest) const;
      void getOutputs(const std::vector<COutPoint> &vOutpoints, std::vector<COutput> &vOutputs);
      bool isSpent(const COutPoint &outpoint) const;
      void listCoins(std::map<QString, std::vector<COutput> > &mapCoins) const;
  
      bool isLockedCoin(uint256 hash, unsigned int n) const;
      void lockCoin(COutPoint &output);
      void unlockCoin(COutPoint &output);
      void listLockedCoins(std::vector<COutPoint> &vOutpts);
  
      void loadReceiveRequests(std::vector<std::string> &vReceiveRequests);
      bool saveReceiveRequest(const std::string &sAddress, const int64_t nId, const std::string &sRequest);
  
  private:
      CWallet *wallet;
      bool fHaveWatchOnly;
      bool fForceCheckBalanceChanged;
  
      // Wallet has an options model for wallet-specific options
      // (transaction fee, for example)
      OptionsModel *optionsModel;
  
      AddressTableModel *addressTableModel;
      TransactionTableModel *transactionTableModel;
      RecentRequestsTableModel *recentRequestsTableModel;
  
      // Cache some values to be able to detect changes
      CAmount cachedBalance;
      CAmount cachedUnconfirmedBalance;
      CAmount cachedImmatureBalance;
      CAmount cachedWatchOnlyBalance;
      CAmount cachedWatchUnconfBalance;
      CAmount cachedWatchImmatureBalance;
      EncryptionStatus cachedEncryptionStatus;
      int cachedNumBlocks;
  
      QTimer *pollTimer;
  
      void subscribeToCoreSignals();
      void unsubscribeFromCoreSignals();
      void checkBalanceChanged();
  
  Q_SIGNALS:
      // Signal that balance in wallet changed
      void balanceChanged(const CAmount &balance,
          const CAmount &unconfirmedBalance,
          const CAmount &immatureBalance,
          const CAmount &watchOnlyBalance,
          const CAmount &watchUnconfBalance,
          const CAmount &watchImmatureBalance);
  
      // Encryption status of wallet changed
      void encryptionStatusChanged(int status);
  
      // Signal emitted when wallet needs to be unlocked
      // It is valid behaviour for listeners to keep the wallet locked after this signal;
      // this means that the unlocking failed or was cancelled.
      void requireUnlock();
  
      // Fired when a message should be reported to the user
      void message(const QString &title, const QString &message, unsigned int style);
  
      // Coins sent: from wallet, to recipient, in (serialized) transaction:
      void coinsSent(CWallet *wallet, SendCoinsRecipient recipient, QByteArray transaction);
  
      // Show progress dialog e.g. for rescan
      void showProgress(const QString &title, int nProgress);
  
      // Watch-only address added
      void notifyWatchonlyChanged(bool fHaveWatchonly);
  
  public Q_SLOTS:
      /* Wallet status might have changed */
      void updateStatus();
      /* New transaction, or transaction changed status */
      void updateTransaction();
      /* New, updated or removed address book entry */
      void updateAddressBook(const QString &address,
          const QString &label,
          bool isMine,
          const QString &purpose,
          int status);
      /* Watch-only added */
      void updateWatchOnlyFlag(bool fHaveWatchonly);
      /* Current, immature or unconfirmed balance might have changed - emit 'balanceChanged' if so */
      void pollBalanceChanged();
  };
  
  #endif // BITCOIN_QT_WALLETMODEL_H
  