text: // Copyright (c) 2011-2019 The Bitcoin Core developers
  // Distributed under the MIT software license, see the accompanying
  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
  
  #ifndef BITCOIN_QT_WALLETMODEL_H
  #define BITCOIN_QT_WALLETMODEL_H
  
  #include <amount.h>
  #include <key.h>
  #include <serialize.h>
  #include <script/standard.h>
  #include "wallet/wallet.h"
  
  #if defined(HAVE_CONFIG_H)
  #include <config/bitcoin-config.h>
  #endif
  
  #ifdef ENABLE_BIP70
  #include <qt/paymentrequestplus.h>
  #endif
  #include <qt/walletmodeltransaction.h>
  
  #include <interfaces/wallet.h>
  #include <support/allocators/secure.h>
  
  #include <map>
  #include <vector>
  
  #include <QObject>
  
  enum class OutputType;
  
  class AddressTableModel;
  class OptionsModel;
  class PlatformStyle;
  class RecentRequestsTableModel;
  class TransactionTableModel;
  class WalletModelTransaction;
  class ContractTableModel;
  
  class CCoinControl;
  class CKeyID;
  class COutPoint;
  class COutput;
  class CPubKey;
  class uint256;
  
  namespace interfaces {
  class Node;
  } // namespace interfaces
  
  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):
          address(addr), label(_label), amount(_amount), message(_message), 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;
      AvailableCoinsType inputType;
      bool useInstanTX;
      CAmount amount;
      // If from a payment request, this is used for storing the memo
      QString message;
  
  #ifdef ENABLE_BIP70
      // If from a payment request, paymentRequest.IsInitialized() will be true
      PaymentRequestPlus paymentRequest;
  #else
      // If building with BIP70 is disabled, keep the payment request around as
      // serialized string to ensure load/store is lossless
      std::string sPaymentRequest;
  #endif
      // Empty if no authentication or invalid signature/cert/etc.
      QString authenticatedMerchant;
  
      bool fSubtractFeeFromAmount; // memory only
  
      static const int CURRENT_VERSION = 1;
      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();
  #ifdef ENABLE_BIP70
          std::string sPaymentRequest;
          if (!ser_action.ForRead() && paymentRequest.IsInitialized())
              paymentRequest.SerializeToString(&sPaymentRequest);
  #endif
          std::string sAuthenticatedMerchant = authenticatedMerchant.toStdString();
  
          READWRITE(this->nVersion);
          READWRITE(sAddress);
          READWRITE(sLabel);
          READWRITE(amount);
          READWRITE(sMessage);
          READWRITE(sPaymentRequest);
          READWRITE(sAuthenticatedMerchant);
  
          if (ser_action.ForRead())
          {
              address = QString::fromStdString(sAddress);
              label = QString::fromStdString(sLabel);
              message = QString::fromStdString(sMessage);
  #ifdef ENABLE_BIP70
              if (!sPaymentRequest.empty())
                  paymentRequest.parse(QByteArray::fromRawData(sPaymentRequest.data(), sPaymentRequest.size()));
  #endif
              authenticatedMerchant = QString::fromStdString(sAuthenticatedMerchant);
          }
      }
  };
  
  /** Interface to Bitcoin wallet from Qt view code. */
  class WalletModel : public QObject
  {
      Q_OBJECT
  
  public:
      explicit WalletModel(std::unique_ptr<interfaces::Wallet> wallet, interfaces::Node& node, const PlatformStyle *platformStyle, OptionsModel *optionsModel, QObject *parent = nullptr);
      ~WalletModel();
  
      enum StatusCode // Returned by sendCoins
      {
          OK,
          InvalidAmount,
          InvalidAddress,
          AmountExceedsBalance,
          AmountWithFeeExceedsBalance,
          DuplicateAddress,
          TransactionCreationFailed, // Error returned when wallet is still locked
          TransactionCommitFailed,
          AbsurdFee,
          PaymentRequestExpired
          //StakingOnlyUnlocked,
          //InsaneFee
      };
  
      enum EncryptionStatus
      {
          Unencrypted,  // !wallet->IsCrypted()
          Locked,       // wallet->IsCrypted() && wallet->IsLocked()
          Unlocked,      // wallet->IsCrypted() && !wallet->IsLocked()
          //UnlockedForStakingOnly   // wallet->IsCrypted() && !wallet->IsLocked() && wallet->fWalletUnlockStakingOnly
      };
  
      OptionsModel *getOptionsModel();
      AddressTableModel *getAddressTableModel();
      ContractTableModel *getContractTableModel();
      TransactionTableModel *getTransactionTableModel();
      RecentRequestsTableModel *getRecentRequestsTableModel();
      //TokenItemModel *getTokenItemModel();
      //TokenTransactionTableModel *getTokenTransactionTableModel();
      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, QString _reasonCommitFailed = "")
              : status(_status),
                reasonCommitFailed(_reasonCommitFailed)
          {
          }
          StatusCode status;
          QString reasonCommitFailed;
      };
  
      // prepare transaction for getting txfee before sending coins
      SendCoinsReturn prepareTransaction(WalletModelTransaction &transaction, const CCoinControl& coinControl);
  
      // 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);
  
      // 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();
  
      void loadReceiveRequests(std::vector<std::string>& vReceiveRequests);
      bool saveReceiveRequest(const std::string &sAddress, const int64_t nId, const std::string &sRequest);
  
      bool bumpFee(uint256 hash, uint256& new_hash);
  
      static bool isWalletEnabled();
      bool privateKeysDisabled() const;
      bool canGetAddresses() const;
  
      interfaces::Node& node() const { return m_node; }
      interfaces::Wallet& wallet() const { return *m_wallet; }
  
      QString getWalletName() const;
      QString getDisplayName() const;
  
      bool isMultiwallet();
  
      AddressTableModel* getAddressTableModel() const { return addressTableModel; }
  private:
      std::unique_ptr<interfaces::Wallet> m_wallet;
      std::unique_ptr<interfaces::Handler> m_handler_unload;
      std::unique_ptr<interfaces::Handler> m_handler_status_changed;
      std::unique_ptr<interfaces::Handler> m_handler_address_book_changed;
      std::unique_ptr<interfaces::Handler> m_handler_transaction_changed;
      std::unique_ptr<interfaces::Handler> m_handler_show_progress;
      std::unique_ptr<interfaces::Handler> m_handler_watch_only_changed;
      std::unique_ptr<interfaces::Handler> m_handler_can_get_addrs_changed;
      std::unique_ptr<interfaces::Handler> m_handler_notify_contract_book_changed;
      interfaces::Node& m_node;
  
      bool fHaveWatchOnly;
      bool fForceCheckBalanceChanged{false};
  
      // Wallet has an options model for wallet-specific options
      // (transaction fee, for example)
      OptionsModel *optionsModel;
  
      AddressTableModel *addressTableModel;
      ContractTableModel *contractTableModel;
      TransactionTableModel *transactionTableModel;
      RecentRequestsTableModel *recentRequestsTableModel;
  
      // Cache some values to be able to detect changes
      interfaces::WalletBalances m_cached_balances;
      EncryptionStatus cachedEncryptionStatus;
      int cachedNumBlocks;
  
      QTimer *pollTimer;
  
      void subscribeToCoreSignals();
      void unsubscribeFromCoreSignals();
      void checkBalanceChanged(const interfaces::WalletBalances& new_balances);
  
  Q_SIGNALS:
      // Signal that balance in wallet changed
      void balanceChanged(const interfaces::WalletBalances& balances);
  
      // Encryption status of wallet changed
      void encryptionStatusChanged();
  
      // 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(WalletModel* 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);
  
      // Signal that wallet is about to be removed
      void unload();
  
      // Notify that there are now keys in the keypool
      void canGetAddressesChanged();
  
  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
  