#define PPCOIN_KERNEL_H
#include "main.h"
+#include "wallet.h"
+
+// ChainDB upgrade time
+extern unsigned int nModifierUpgradeTime;
// MODIFIER_INTERVAL: time to elapse before new modifier is computed
extern unsigned int nModifierInterval;
// ratio of group interval length between the last group and the first group
static const int MODIFIER_INTERVAL_RATIO = 3;
+// Whether the given block is subject to new modifier protocol
+bool IsFixedModifierInterval(unsigned int nTimeBlock);
+
// Compute the hash modifier for proof-of-stake
-bool ComputeNextStakeModifier(const CBlockIndex* pindexPrev, uint64& nStakeModifier, bool& fGeneratedStakeModifier);
+bool ComputeNextStakeModifier(const CBlockIndex* pindexCurrent, uint64_t& nStakeModifier, bool& fGeneratedStakeModifier);
+
+// The stake modifier used to hash for a stake kernel is chosen as the stake
+// modifier about a selection interval later than the coin generating the kernel
+bool GetKernelStakeModifier(uint256 hashBlockFrom, uint64_t& nStakeModifier);
// Check whether stake kernel meets hash target
// Sets hashProofOfStake on success return
-bool CheckStakeKernelHash(unsigned int nBits, const CBlock& blockFrom, unsigned int nTxPrevOffset, const CTransaction& txPrev, const COutPoint& prevout, unsigned int nTimeTx, uint256& hashProofOfStake, uint256& targetProofOfStake, bool fPrintProofOfStake=false);
+bool CheckStakeKernelHash(unsigned int nBits, const CBlock& blockFrom, uint32_t nTxPrevOffset, const CTransaction& txPrev, const COutPoint& prevout, uint32_t nTimeTx, uint256& hashProofOfStake, uint256& targetProofOfStake, bool fPrintProofOfStake=false);
+
+// Scan given kernel for solutions
+bool ScanKernelForward(unsigned char *kernel, uint32_t nBits, uint32_t nInputTxTime, int64_t nValueIn, std::pair<uint32_t, uint32_t> &SearchInterval, std::vector<std::pair<uint256, uint32_t> > &solutions);
// Check kernel hash target and coinstake signature
// Sets hashProofOfStake on success return
bool CheckProofOfStake(const CTransaction& tx, unsigned int nBits, uint256& hashProofOfStake, uint256& targetProofOfStake);
// Get stake modifier checksum
-unsigned int GetStakeModifierChecksum(const CBlockIndex* pindex);
+uint32_t GetStakeModifierChecksum(const CBlockIndex* pindex);
// Check stake modifier hard checkpoints
-bool CheckStakeModifierCheckpoints(int nHeight, unsigned int nStakeModifierChecksum);
+bool CheckStakeModifierCheckpoints(int nHeight, uint32_t nStakeModifierChecksum);
// Get time weight using supplied timestamps
-int64 GetWeight(int64 nIntervalBeginning, int64 nIntervalEnd);
-
-#endif // PPCOIN_KERNEL_H
+inline int64_t GetWeight(int64_t nIntervalBeginning, int64_t nIntervalEnd)
+{
+ // Kernel hash weight starts from 0 at the 30-day min age
+ // this change increases active coins participating the hash and helps
+ // to secure the network when proof-of-stake difficulty is low
+ //
+ // Maximum TimeWeight is 90 days.
+
+ return std::min(nIntervalEnd - nIntervalBeginning - nStakeMinAge, (int64_t)nStakeMaxAge);
+}
+
+#endif // PPCOIN_KERNEL_H
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