text: // Copyright (c) 2012-2013 The PPCoin developers
  // Copyright (c) 2015-2018 The PIVX developers
  // Copyright (c) 2017-2018 The HUZU developers
  // Copyright (c) 2018-2019 The ZIJA developers
  // Copyright (c) 2019 The 2PAY developers
  // Distributed under the MIT/X11 software license, see the accompanying
  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
  #ifndef BITCOIN_KERNEL_H
  #define BITCOIN_KERNEL_H
  
  #include "main.h"
  #include "stakeinput.h"
  
  
  // MODIFIER_INTERVAL: time to elapse before new modifier is computed
  static const unsigned int MODIFIER_INTERVAL = 60;
  static const unsigned int MODIFIER_INTERVAL_TESTNET = 60;
  extern unsigned int nModifierInterval;
  extern unsigned int getIntervalVersion(bool fTestNet);
  
  // MODIFIER_INTERVAL_RATIO:
  // ratio of group interval length between the last group and the first group
  static const int MODIFIER_INTERVAL_RATIO = 3;
  
  // Compute the hash modifier for proof-of-stake
  bool GetKernelStakeModifier(uint256 hashBlockFrom, uint64_t& nStakeModifier, int& nStakeModifierHeight, int64_t& nStakeModifierTime, bool fPrintProofOfStake);
  bool ComputeNextStakeModifier(const CBlockIndex* pindexPrev, uint64_t& nStakeModifier, bool& fGeneratedStakeModifier);
  
  bool CheckStake(const CDataStream& ssUniqueID, CAmount nValueIn, const uint64_t nStakeModifier, const uint256& bnTarget, unsigned int nTimeBlockFrom, unsigned int& nTimeTx, uint256& hashProofOfStake);
  bool stakeTargetHit(uint256 hashProofOfStake, int64_t nValueIn, uint256 bnTargetPerCoinDay);
  bool Stake(CStakeInput* stakeInput, unsigned int nBits, unsigned int nTimeBlockFrom, unsigned int& nTimeTx, uint256& hashProofOfStake);
  
  // Check kernel hash target and coinstake signature
  // Sets hashProofOfStake on success return
  bool CheckProofOfStake(const CBlock block, uint256& hashProofOfStake, std::unique_ptr<CStakeInput>& stake);
  
  // Check whether the coinstake timestamp meets protocol
  bool CheckCoinStakeTimestamp(int64_t nTimeBlock, int64_t nTimeTx);
  
  // Get stake modifier checksum
  unsigned int GetStakeModifierChecksum(const CBlockIndex* pindex);
  
  // Check stake modifier hard checkpoints
  bool CheckStakeModifierCheckpoints(int nHeight, unsigned int nStakeModifierChecksum);
  
  // Get time weight using supplied timestamps
  int64_t GetWeight(int64_t nIntervalBeginning, int64_t nIntervalEnd);
  
  #endif // BITCOIN_KERNEL_H
  