text: // Copyright (c) 2009-2010 Satoshi Nakamoto
  // Copyright (c) 2009-2018 The Bitcoin Core developers
  // Copyright (c) 2020 The bitcoinR Core developers
  // Distributed under the MIT software license, see the accompanying
  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
  
  #ifndef BITCOINR_CHAINPARAMS_H
  #define BITCOINR_CHAINPARAMS_H
  
  #include <chainparamsbase.h>
  #include <consensus/params.h>
  #include <primitives/block.h>
  #include <protocol.h>
  
  #include <memory>
  #include <vector>
  
  struct SeedSpec6 {
      uint8_t addr[16];
      uint16_t port;
  };
  
  typedef std::map<int, uint256> MapCheckpoints;
  
  struct CCheckpointData {
      MapCheckpoints mapCheckpoints;
  };
  
  /**
   * Holds various statistics on transactions within a chain. Used to estimate
   * verification progress during chain sync.
   *
   * See also: CChainParams::TxData, GuessVerificationProgress.
   */
  struct ChainTxData {
      int64_t nTime;    //!< UNIX timestamp of last known number of transactions
      int64_t nTxCount; //!< total number of transactions between genesis and that timestamp
      double dTxRate;   //!< estimated number of transactions per second after that timestamp
  };
  
  /**
   * CChainParams defines various tweakable parameters of a given instance of the
   * bitcoinR system. There are three: the main network on which people trade goods
   * and services, the public test network which gets reset from time to time and
   * a regression test mode which is intended for private networks only. It has
   * minimal difficulty to ensure that blocks can be found instantly.
   */
  class CChainParams
  {
  public:
      enum Base58Type {
          PUBKEY_ADDRESS,
          SCRIPT_ADDRESS,
          SECRET_KEY,
          EXT_PUBLIC_KEY,
          EXT_SECRET_KEY,
  
          MAX_BASE58_TYPES
      };
  
      const Consensus::Params& GetConsensus() const { return consensus; }
      const CMessageHeader::MessageStartChars& MessageStart() const { return pchMessageStart; }
      int GetDefaultPort() const { return nDefaultPort; }
  
      const CBlock& GenesisBlock() const { return genesis; }
      /** Default value for -checkmempool and -checkblockindex argument */
      bool DefaultConsistencyChecks() const { return fDefaultConsistencyChecks; }
      /** Policy: Filter transactions that do not match well-defined patterns */
      bool RequireStandard() const { return fRequireStandard; }
      uint64_t PruneAfterHeight() const { return nPruneAfterHeight; }
      /** Make miner stop after a block is found. In RPC, don't return until nGenProcLimit blocks are generated */
      bool MineBlocksOnDemand() const { return fMineBlocksOnDemand; }
      /** Return the BIP70 network string (main, test or regtest) */
      std::string NetworkIDString() const { return strNetworkID; }
      /** Return true if the fallback fee is by default enabled for this network */
      bool IsFallbackFeeEnabled() const { return m_fallback_fee_enabled; }
      /** Return the list of hostnames to look up for DNS seeds */
      const std::vector<std::string>& DNSSeeds() const { return vSeeds; }
      const std::vector<unsigned char>& Base58Prefix(Base58Type type) const { return base58Prefixes[type]; }
      const std::string& Bech32HRP() const { return bech32_hrp; }
      const std::vector<SeedSpec6>& FixedSeeds() const { return vFixedSeeds; }
      const CCheckpointData& Checkpoints() const { return checkpointData; }
      const ChainTxData& TxData() const { return chainTxData; }
      void UpdateVersionBitsParameters(Consensus::DeploymentPos d, int64_t nStartTime, int64_t nTimeout);
  protected:
      CChainParams() {}
  
      Consensus::Params consensus;
      CMessageHeader::MessageStartChars pchMessageStart;
      int nDefaultPort;
      uint64_t nPruneAfterHeight;
      std::vector<std::string> vSeeds;
      std::vector<unsigned char> base58Prefixes[MAX_BASE58_TYPES];
      std::string bech32_hrp;
      std::string strNetworkID;
      CBlock genesis;
      std::vector<SeedSpec6> vFixedSeeds;
      bool fDefaultConsistencyChecks;
      bool fRequireStandard;
      bool fMineBlocksOnDemand;
      CCheckpointData checkpointData;
      ChainTxData chainTxData;
      bool m_fallback_fee_enabled;
  };
  
  /**
   * Creates and returns a std::unique_ptr<CChainParams> of the chosen chain.
   * @returns a CChainParams* of the chosen chain.
   * @throws a std::runtime_error if the chain is not supported.
   */
  std::unique_ptr<CChainParams> CreateChainParams(const std::string& chain);
  
  /**
   * Return the currently selected parameters. This won't change after app
   * startup, except for unit tests.
   */
  const CChainParams &Params();
  
  /**
   * Sets the params returned by Params() to those for the given BIP70 chain name.
   * @throws std::runtime_error when the chain is not supported.
   */
  void SelectParams(const std::string& chain);
  
  /**
   * Allows modifying the Version Bits regtest parameters.
   */
  void UpdateVersionBitsParameters(Consensus::DeploymentPos d, int64_t nStartTime, int64_t nTimeout);
  
  #endif // BITCOINR_CHAINPARAMS_H
  