text: // Copyright (c) 2018 The Bitcoin Core developers
  // Distributed under the MIT software license, see the accompanying
  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
  
  #ifndef BITCOIN_INTERFACES_NODE_H
  #define BITCOIN_INTERFACES_NODE_H
  
  #include <amount.h>     // For Amount
  #include <net.h>        // For CConnman::NumConnections
  #include <net_types.h>  // For banmap_t
  #include <netaddress.h> // For Network
  
  #include <support/allocators/secure.h> // For SecureString
  #include <util/translation.h>
  
  #include <cstddef>
  #include <cstdint>
  #include <functional>
  #include <memory>
  #include <string>
  #include <tuple>
  #include <vector>
  
  class BanMan;
  class CCoinControl;
  class CFeeRate;
  struct CNodeStateStats;
  struct CNodeStats;
  class Coin;
  class Config;
  class HTTPRPCRequestProcessor;
  struct NodeContext;
  class proxyType;
  class RPCServer;
  class RPCTimerInterface;
  enum class SynchronizationState;
  class UniValue;
  enum class WalletCreationStatus;
  struct bilingual_str;
  
  namespace interfaces {
  class Handler;
  class Wallet;
  struct BlockTip;
  
  //! Block and header tip information
  struct BlockAndHeaderTipInfo {
      int block_height;
      int64_t block_time;
      int header_height;
      int64_t header_time;
      double verification_progress;
  };
  
  //! Top-level interface for a bitcoin node (bitcoind process).
  class Node {
  public:
      virtual ~Node() {}
  
      //! Init logging.
      virtual void initLogging() = 0;
  
      //! Init parameter interaction.
      virtual void initParameterInteraction() = 0;
  
      //! Get warnings.
      virtual bilingual_str getWarnings() = 0;
  
      //! Initialize app dependencies.
      virtual bool baseInitialize(Config &config) = 0;
  
      //! Start node.
      virtual bool
      appInitMain(Config &config, RPCServer &rpcServer,
                  HTTPRPCRequestProcessor &httpRPCRequestProcessor,
                  interfaces::BlockAndHeaderTipInfo *tip_info = nullptr) = 0;
  
      //! Stop node.
      virtual void appShutdown() = 0;
  
      //! Start shutdown.
      virtual void startShutdown() = 0;
  
      //! Return whether shutdown was requested.
      virtual bool shutdownRequested() = 0;
  
      //! Map port.
      virtual void mapPort(bool use_upnp) = 0;
  
      //! Get proxy.
      virtual bool getProxy(Network net, proxyType &proxy_info) = 0;
  
      //! Get number of connections.
      virtual size_t getNodeCount(CConnman::NumConnections flags) = 0;
  
      //! Get stats for connected nodes.
      using NodesStats =
          std::vector<std::tuple<CNodeStats, bool, CNodeStateStats>>;
      virtual bool getNodesStats(NodesStats &stats) = 0;
  
      //! Get ban map entries.
      virtual bool getBanned(banmap_t &banmap) = 0;
  
      //! Ban node.
      virtual bool ban(const CNetAddr &net_addr, int64_t ban_time_offset) = 0;
  
      //! Unban node.
      virtual bool unban(const CSubNet &ip) = 0;
  
      //! Disconnect node by address.
      virtual bool disconnectByAddress(const CNetAddr &net_addr) = 0;
  
      //! Disconnect node by id.
      virtual bool disconnectById(NodeId id) = 0;
  
      //! Get total bytes recv.
      virtual int64_t getTotalBytesRecv() = 0;
  
      //! Get total bytes sent.
      virtual int64_t getTotalBytesSent() = 0;
  
      //! Get mempool size.
      virtual size_t getMempoolSize() = 0;
  
      //! Get mempool dynamic usage.
      virtual size_t getMempoolDynamicUsage() = 0;
  
      //! Get header tip height and time.
      virtual bool getHeaderTip(int &height, int64_t &block_time) = 0;
  
      //! Get num blocks.
      virtual int getNumBlocks() = 0;
  
      //! Get best block hash.
      virtual BlockHash getBestBlockHash() = 0;
  
      //! Get last block time.
      virtual int64_t getLastBlockTime() = 0;
  
      //! Get verification progress.
      virtual double getVerificationProgress() = 0;
  
      //! Is initial block download.
      virtual bool isInitialBlockDownload() = 0;
  
      //! Get reindex.
      virtual bool getReindex() = 0;
  
      //! Get importing.
      virtual bool getImporting() = 0;
  
      //! Set network active.
      virtual void setNetworkActive(bool active) = 0;
  
      //! Get network active.
      virtual bool getNetworkActive() = 0;
  
      //! Estimate smart fee.
      virtual CFeeRate estimateSmartFee() = 0;
  
      //! Get dust relay fee.
      virtual CFeeRate getDustRelayFee() = 0;
  
      //! Execute rpc command.
      virtual UniValue executeRpc(Config &config, const std::string &command,
                                  const UniValue &params,
                                  const std::string &uri) = 0;
  
      //! List rpc commands.
      virtual std::vector<std::string> listRpcCommands() = 0;
  
      //! Set RPC timer interface if unset.
      virtual void rpcSetTimerInterfaceIfUnset(RPCTimerInterface *iface) = 0;
  
      //! Unset RPC timer interface.
      virtual void rpcUnsetTimerInterface(RPCTimerInterface *iface) = 0;
  
      //! Get unspent outputs associated with a transaction.
      virtual bool getUnspentOutput(const COutPoint &output, Coin &coin) = 0;
  
      //! Return default wallet directory.
      virtual std::string getWalletDir() = 0;
  
      //! Return available wallets in wallet directory.
      virtual std::vector<std::string> listWalletDir() = 0;
  
      //! Return interfaces for accessing wallets (if any).
      virtual std::vector<std::unique_ptr<Wallet>> getWallets() = 0;
  
      //! Attempts to load a wallet from file or directory.
      //! The loaded wallet is also notified to handlers previously registered
      //! with handleLoadWallet.
      virtual std::unique_ptr<Wallet>
      loadWallet(const CChainParams &params, const std::string &name,
                 bilingual_str &error,
                 std::vector<bilingual_str> &warnings) const = 0;
  
      //! Create a wallet from file
      virtual std::unique_ptr<Wallet>
      createWallet(const CChainParams &params, const SecureString &passphrase,
                   uint64_t wallet_creation_flags, const std::string &name,
                   bilingual_str &error, std::vector<bilingual_str> &warnings,
                   WalletCreationStatus &status) = 0;
  
      //! Register handler for init messages.
      using InitMessageFn = std::function<void(const std::string &message)>;
      virtual std::unique_ptr<Handler> handleInitMessage(InitMessageFn fn) = 0;
  
      //! Register handler for message box messages.
      using MessageBoxFn =
          std::function<bool(const bilingual_str &message,
                             const std::string &caption, unsigned int style)>;
      virtual std::unique_ptr<Handler> handleMessageBox(MessageBoxFn fn) = 0;
  
      //! Register handler for question messages.
      using QuestionFn =
          std::function<bool(const bilingual_str &message,
                             const std::string &non_interactive_message,
                             const std::string &caption, unsigned int style)>;
      virtual std::unique_ptr<Handler> handleQuestion(QuestionFn fn) = 0;
  
      //! Register handler for progress messages.
      using ShowProgressFn = std::function<void(
          const std::string &title, int progress, bool resume_possible)>;
      virtual std::unique_ptr<Handler> handleShowProgress(ShowProgressFn fn) = 0;
  
      //! Register handler for load wallet messages.
      using LoadWalletFn = std::function<void(std::unique_ptr<Wallet> wallet)>;
      virtual std::unique_ptr<Handler> handleLoadWallet(LoadWalletFn fn) = 0;
  
      //! Register handler for number of connections changed messages.
      using NotifyNumConnectionsChangedFn =
          std::function<void(int new_num_connections)>;
      virtual std::unique_ptr<Handler>
      handleNotifyNumConnectionsChanged(NotifyNumConnectionsChangedFn fn) = 0;
  
      //! Register handler for network active messages.
      using NotifyNetworkActiveChangedFn =
          std::function<void(bool network_active)>;
      virtual std::unique_ptr<Handler>
      handleNotifyNetworkActiveChanged(NotifyNetworkActiveChangedFn fn) = 0;
  
      //! Register handler for notify alert messages.
      using NotifyAlertChangedFn = std::function<void()>;
      virtual std::unique_ptr<Handler>
      handleNotifyAlertChanged(NotifyAlertChangedFn fn) = 0;
  
      //! Register handler for ban list messages.
      using BannedListChangedFn = std::function<void()>;
      virtual std::unique_ptr<Handler>
      handleBannedListChanged(BannedListChangedFn fn) = 0;
  
      //! Register handler for block tip messages.
      using NotifyBlockTipFn =
          std::function<void(SynchronizationState, interfaces::BlockTip tip,
                             double verification_progress)>;
      virtual std::unique_ptr<Handler>
      handleNotifyBlockTip(NotifyBlockTipFn fn) = 0;
  
      //! Register handler for header tip messages.
      using NotifyHeaderTipFn =
          std::function<void(SynchronizationState, interfaces::BlockTip tip,
                             double verification_progress)>;
      virtual std::unique_ptr<Handler>
      handleNotifyHeaderTip(NotifyHeaderTipFn fn) = 0;
  
      //! Get and set internal node context. Useful for testing, but not
      //! accessible across processes.
      virtual NodeContext *context() { return nullptr; }
      virtual void setContext(NodeContext *context) {}
  };
  
  //! Return implementation of Node interface.
  std::unique_ptr<Node> MakeNode(NodeContext *context = nullptr);
  
  //! Block tip (could be a header or not, depends on the subscribed signal).
  struct BlockTip {
      int block_height;
      int64_t block_time;
      BlockHash block_hash;
  };
  
  } // namespace interfaces
  
  #endif // BITCOIN_INTERFACES_NODE_H
  