// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2014 The Bitcoin Core developers
// Distributed under the GPLv3 software license, see the accompanying
// file COPYING or https://www.gnu.org/licenses/gpl-3.0.en.html

/******************************************************************************
 * Copyright © 2014-2019 The SuperNET Developers.                             *
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 * See the AUTHORS, DEVELOPER-AGREEMENT and LICENSE files at                  *
 * the top-level directory of this distribution for the individual copyright  *
 * holder information and the developer policies on copyright and licensing.  *
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 * Unless otherwise agreed in a custom licensing agreement, no part of the    *
 * SuperNET software, including this file may be copied, modified, propagated *
 * or distributed except according to the terms contained in the LICENSE file *
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 * Removal or modification of this copyright notice is prohibited.            *
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#ifndef BITCOIN_POW_H
#define BITCOIN_POW_H

#include "chain.h"
#include "consensus/params.h"

#include <stdint.h>

class CBlockHeader;
class CBlockIndex;
class CChainParams;
class uint256;
class arith_uint256;

unsigned int GetNextWorkRequired(const CBlockIndex* pindexLast, const CBlockHeader *pblock, const Consensus::Params&);
unsigned int CalculateNextWorkRequired(arith_uint256 bnAvg,
                                       int64_t nLastBlockTime, int64_t nFirstBlockTime,
                                       const Consensus::Params&);

/** Check whether the Equihash solution in a block header is valid */
bool CheckEquihashSolution(const CBlockHeader *pblock, const CChainParams&);

/** Check whether a block hash satisfies the proof-of-work requirement specified by nBits */
bool CheckProofOfWork(const CBlockHeader &blkHeader, uint8_t *pubkey33, int32_t height, const Consensus::Params& params);
CChainPower GetBlockProof(const CBlockIndex& block);

/** Return the time it would take to redo the work difference between from and to, assuming the current hashrate corresponds to the difficulty at tip, in seconds. */
int64_t GetBlockProofEquivalentTime(const CBlockIndex& to, const CBlockIndex& from, const CBlockIndex& tip, const Consensus::Params&);

#endif // BITCOIN_POW_H