// Copyright (c) 2010 Satoshi Nakamoto
// Copyright (c) 2009-2017 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#include <arith_uint256.h>
#include <chainparams.h>
#include <consensus/merkle.h>

#include <tinyformat.h>
#include <util.h>
#include <utilstrencodings.h>

#include <assert.h>
#include <memory>

#include <chainparamsseeds.h>

static CBlock CreateGenesisBlock(const char* pszTimestamp, const CScript& genesisOutputScript, uint32_t nTime, uint32_t nNonce, uint32_t nBits, int32_t nVersion, const CAmount& genesisReward)
{
    CMutableTransaction txNew;
    txNew.nVersion = 1;
    txNew.vin.resize(1);
    txNew.vout.resize(1);
    txNew.vin[0].scriptSig = CScript() << 486604799 << CScriptNum(4) << std::vector<unsigned char>((const unsigned char*)pszTimestamp, (const unsigned char*)pszTimestamp + strlen(pszTimestamp));
    txNew.vout[0].nValue = genesisReward;
    txNew.vout[0].scriptPubKey = genesisOutputScript;

    CBlock genesis;
    genesis.nTime    = nTime;
    genesis.nBits    = nBits;
    genesis.nNonce   = 0; // Used as height.
    genesis.nVersion = nVersion;
    genesis.vtx.push_back(MakeTransactionRef(std::move(txNew)));
    genesis.hashPrevBlock.SetNull();
    genesis.hashMerkleRoot = BlockMerkleRoot(genesis);

    genesis.cnHeader.major_version  = 10; // Cryptonight variant 4
    genesis.cnHeader.prev_id        = genesis.GetOriginalBlockHash();
    genesis.cnHeader.nonce          = nNonce;
    return genesis;
}

static CBlock CreateGenesisBlock(uint32_t nTime, uint32_t nNonce, uint32_t nBits, int32_t nVersion, const CAmount& genesisReward)
{
    // RELEASE TODO: change timestamp
    const char* pszTimestamp = "The Economist 05/Dec/2018 The US-China trade war is on hold";
    const CScript genesisOutputScript = CScript() << ParseHex("a914676a24ba4bfadd458e5245b26fa57f9a62ca185087");
    return CreateGenesisBlock(pszTimestamp, genesisOutputScript, nTime, nNonce, nBits, nVersion, genesisReward);
}

void CChainParams::UpdateVersionBitsParameters(Consensus::DeploymentPos d, int64_t nStartTime, int64_t nTimeout)
{
    consensus.vDeployments[d].nStartTime = nStartTime;
    consensus.vDeployments[d].nTimeout = nTimeout;
}

/**
 * Main network
 */
/**
 * What makes a good checkpoint block?
 * + Is surrounded by blocks with reasonable timestamps
 *   (no blocks before with a timestamp after, none after with
 *    timestamp before)
 * + Contains no strange transactions
 */

class CMainParams : public CChainParams {
public:
    CMainParams() {
        strNetworkID = "main";
        consensus.nSubsidyHalvingInterval = 1050000; // 210000 * 5
        consensus.BIP16Height = 1;
        consensus.BIP34Height = 1;
        consensus.BIP65Height = 1;
        consensus.BIP66Height = 1;
        consensus.powLimit = uint256S("000fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff");
        consensus.nPowTargetTimespan = 2.0 * 60; // Two minutes
        consensus.nPowTargetSpacing = 2.0 * 60; // Two minutes
        consensus.fPowAllowMinDifficultyBlocks = false;
        consensus.fPowNoRetargeting = false;
        consensus.nRuleChangeActivationThreshold = 6048; // 75% of 8064
        consensus.nMinerConfirmationWindow = 8064; // nPowTargetTimespan / nPowTargetSpacing * 4
        consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].bit = 28;
        consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nStartTime = 1199145601; // January 1, 2008
        consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = 1230767999; // December 31, 2008

        // Deployment of BIP68, BIP112, and BIP113.
        consensus.vDeployments[Consensus::DEPLOYMENT_CSV].bit = 0;
        //consensus.vDeployments[Consensus::DEPLOYMENT_CSV].nStartTime = 1485561600; // January 28, 2017
        consensus.vDeployments[Consensus::DEPLOYMENT_CSV].nStartTime = -1; // Consensus::BIP9Deployment::ALWAYS_ACTIVE
        consensus.vDeployments[Consensus::DEPLOYMENT_CSV].nTimeout = 1517356801; // January 31st, 2018

        // Deployment of SegWit (BIP141, BIP143, and BIP147)
        consensus.vDeployments[Consensus::DEPLOYMENT_SEGWIT].bit = 1;
        //consensus.vDeployments[Consensus::DEPLOYMENT_SEGWIT].nStartTime = 1485561600; // January 28, 2017
        consensus.vDeployments[Consensus::DEPLOYMENT_SEGWIT].nStartTime = -1; // Consensus::BIP9Deployment::ALWAYS_ACTIVE
        consensus.vDeployments[Consensus::DEPLOYMENT_SEGWIT].nTimeout = 1517356801; // January 31st, 2018

        // The best chain should have at least this much work.
        consensus.nMinimumChainWork = uint256S("0x0000000000000000000000000000000000000000000000000000000000100000");

        // By default assume that the signatures in ancestors of this block are valid.
        consensus.defaultAssumeValid = uint256S("0x66f49ad85624c33e4fd61aa45c54012509ed4a53308908dd07f56346c7939273");

        /**
         * The message start string is designed to be unlikely to occur in normal data.
         * The characters are rarely used upper ASCII, not valid as UTF-8, and produce
         * a large 32-bit integer with any alignment.
         */
        pchMessageStart[0] = 0x6a;
        pchMessageStart[1] = 0xc6;
        pchMessageStart[2] = 0x07;
        pchMessageStart[3] = 0x9a;
        nDefaultPort = 9338;
        nPruneAfterHeight = 100000;

        const uint32_t genesisBlockReward = 0.00001 * COIN; // A small reward for the core developers :-)
        //TODO: target: 0x1e0fffff, update timestampe and nonce.
        genesis = CreateGenesisBlock(1553145843, 6146, 0x1f0ffff0, 1, genesisBlockReward);
        consensus.hashGenesisBlock = genesis.GetHash();
        assert(consensus.hashGenesisBlock == uint256S("0xbad6e50683aa6032b9ea9bbbc67a6b4621612221176b963fc9ce9ae10a77effd"));
        assert(genesis.hashMerkleRoot == uint256S("0xb21d4680875c0e472b7dbf3dbab2aaeb2dbbb5fa8b154f978b5ea0706d1fd5b9"));

        // Note that of those with the service bits flag, most only support a subset of possible options
        vSeeds.emplace_back("dnsseed.kevacoin.org");
        vSeeds.emplace_back("dnsseed.honourchat.com");

        base58Prefixes[PUBKEY_ADDRESS] = std::vector<unsigned char>(1,45); // K
        base58Prefixes[SCRIPT_ADDRESS] = std::vector<unsigned char>(1,5);
        base58Prefixes[SCRIPT_ADDRESS2] = std::vector<unsigned char>(1,70); // V
        base58Prefixes[SECRET_KEY] =     std::vector<unsigned char>(1,139); // M
        base58Prefixes[EXT_PUBLIC_KEY] = {0x04, 0x88, 0xB2, 0x1E};
        base58Prefixes[EXT_SECRET_KEY] = {0x04, 0x88, 0xAD, 0xE4};
        base58Prefixes[KEVA_NAMESPACE] = std::vector<unsigned char>(1,53); // N

        bech32_hrp = "kva";

        vFixedSeeds = std::vector<SeedSpec6>(pnSeed6_main, pnSeed6_main + ARRAYLEN(pnSeed6_main));

        fDefaultConsistencyChecks = false;
        fRequireStandard = true;
        fMineBlocksOnDemand = false;

        checkpointData = {
            {
            }
        };

        chainTxData = ChainTxData{
        };
    }

    int DefaultCheckKevaDB() const
    {
        return -1;
    }
};

/**
 * Testnet (v7)
 */
class CTestNetParams : public CChainParams {
public:
    CTestNetParams() {
        strNetworkID = "test";
        consensus.nSubsidyHalvingInterval = 840000;
        consensus.BIP16Height = 0; // always enforce P2SH BIP16 on regtest
        consensus.BIP34Height = 1;
        consensus.BIP34Hash = uint256S("0xa8dbaa66a9266348f6527fe528efea73227d51938befb81d5a1521cebd319c4a"); // Genesis
        consensus.BIP65Height = 1;
        consensus.BIP66Height = 1;
        consensus.powLimit = uint256S("000fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff");
        consensus.nPowTargetTimespan = 2.0 * 60; // Two minutes
        consensus.nPowTargetSpacing = 2.0 * 60; // Two minutes
        consensus.fPowAllowMinDifficultyBlocks = true;
        consensus.fPowNoRetargeting = false;
        consensus.nRuleChangeActivationThreshold = 1512; // 75% for testchains
        consensus.nMinerConfirmationWindow = 2016; // nPowTargetTimespan / nPowTargetSpacing
        consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].bit = 28;
        consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nStartTime = 1199145601; // January 1, 2008
        consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = 1230767999; // December 31, 2008

        // Deployment of BIP68, BIP112, and BIP113.
        consensus.vDeployments[Consensus::DEPLOYMENT_CSV].bit = 0;
        //consensus.vDeployments[Consensus::DEPLOYMENT_CSV].nStartTime = 1483228800; // January 1, 2017
        consensus.vDeployments[Consensus::DEPLOYMENT_CSV].nStartTime = -1; // Consensus::BIP9Deployment::ALWAYS_ACTIVE
        consensus.vDeployments[Consensus::DEPLOYMENT_CSV].nTimeout = 1517356801; // January 31st, 2018

        // Deployment of SegWit (BIP141, BIP143, and BIP147)
        consensus.vDeployments[Consensus::DEPLOYMENT_SEGWIT].bit = 1;
        //consensus.vDeployments[Consensus::DEPLOYMENT_SEGWIT].nStartTime = 1483228800; // January 1, 2017
        consensus.vDeployments[Consensus::DEPLOYMENT_SEGWIT].nStartTime = -1; // Consensus::BIP9Deployment::ALWAYS_ACTIVE
        consensus.vDeployments[Consensus::DEPLOYMENT_SEGWIT].nTimeout = 1517356801; // January 31st, 2018

        // The best chain should have at least this much work.
        consensus.nMinimumChainWork = uint256S("0x0000000000000000000000000000000000000000000000000000000000100000");

        // By default assume that the signatures in ancestors of this block are valid.
        consensus.defaultAssumeValid = uint256S("0x1efb29c8187d5a496a33377941d1df415169c3ce5d8c05d055f25b683ec3f9a3");

        pchMessageStart[0] = 0xfe;
        pchMessageStart[1] = 0xec;
        pchMessageStart[2] = 0x65;
        pchMessageStart[3] = 0xe4;
        nDefaultPort = 19335;
        nPruneAfterHeight = 1000;

        genesis = CreateGenesisBlock(1553100443, 5758, 0x1f0ffff0, 1, 500 * COIN);
        consensus.hashGenesisBlock = genesis.GetHash();
#if 0
        arith_uint256 hashTarget = arith_uint256().SetCompact(genesis.nBits);
        uint256 hashGenesisBlock = uint256S("0x01");
        if (genesis.GetHash() != hashGenesisBlock) {
            printf("recalculating params for testnet.\n");
            printf("old testnet genesis nonce: %d\n", genesis.cnHeader.nonce);
            printf("old testnet genesis hash:  %s\n", hashGenesisBlock.ToString().c_str());
            // deliberately empty for loop finds nonce value.
            printf("hashTarget is: %s\n", hashTarget.ToString().c_str());
            for(genesis.cnHeader.nonce = 0; hashTarget < UintToArith256(genesis.GetPoWHash()); genesis.cnHeader.nonce++) {
                printf("nNonce: %d\n\n", genesis.cnHeader.nonce);
            }
            printf("new testnet genesis merkle root: %s\n", genesis.hashMerkleRoot.ToString().c_str());
            printf("new testnet genesis nonce: %d\n", genesis.cnHeader.nonce);
            printf("new testnet genesis hash: %s\n", genesis.GetHash().ToString().c_str());
        }
#endif
        assert(consensus.hashGenesisBlock == uint256S("f1b4d0460060c2cdfe4be2e71c15f23338b262b72dfa73c389cc144896a453ec"));
        assert(genesis.hashMerkleRoot == uint256S("3cf6c3b6da3f4058853ee70369ee43d473aca91ae8fc8f44a645beb21c392d80"));

        vFixedSeeds.clear();
        vSeeds.clear();
        // nodes with support for servicebits filtering should be at the top
#if 0
        vSeeds.emplace_back("testnet-seed.kevacoin.org");
        vSeeds.emplace_back("testnet-seed.honourchat.com");
#endif

        base58Prefixes[PUBKEY_ADDRESS] = std::vector<unsigned char>(1,55); // P
        base58Prefixes[SCRIPT_ADDRESS] = std::vector<unsigned char>(1,5);
        base58Prefixes[SCRIPT_ADDRESS2] = std::vector<unsigned char>(1,65); // T
        base58Prefixes[SECRET_KEY] =     std::vector<unsigned char>(1,58); // 9
        base58Prefixes[EXT_PUBLIC_KEY] = {0x04, 0x88, 0xB2, 0x1E};
        base58Prefixes[EXT_SECRET_KEY] = {0x04, 0x88, 0xAD, 0xE4};
        base58Prefixes[KEVA_NAMESPACE] = std::vector<unsigned char>(1,53); // N

        bech32_hrp = "tkva";
#if 0
        vFixedSeeds = std::vector<SeedSpec6>(pnSeed6_test, pnSeed6_test + ARRAYLEN(pnSeed6_test));
#endif

        fDefaultConsistencyChecks = false;
        fRequireStandard = false;
        fMineBlocksOnDemand = false;

        checkpointData = (CCheckpointData) {
            {
            }
        };

        chainTxData = ChainTxData{
        };

    }

    int DefaultCheckKevaDB() const
    {
        return -1;
    }
};

/**
 * Regression test
 */
class CRegTestParams : public CChainParams {
public:
    CRegTestParams() {
        strNetworkID = "regtest";
        consensus.nSubsidyHalvingInterval = 150;
        consensus.BIP16Height = 0; // always enforce P2SH BIP16 on regtest
        consensus.BIP34Height = 100000000; // BIP34 has not activated on regtest (far in the future so block v1 are not rejected in tests)
        consensus.BIP34Hash = uint256();
        consensus.BIP65Height = 1351; // BIP65 activated on regtest (Used in rpc activation tests)
        consensus.BIP66Height = 1251; // BIP66 activated on regtest (Used in rpc activation tests)
        consensus.powLimit = uint256S("7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff");
        consensus.nPowTargetTimespan = 2.0 * 60; // Two minutes
        consensus.nPowTargetSpacing = 2.0 * 60; // Two minutes
        consensus.fPowAllowMinDifficultyBlocks = true;
        consensus.fPowNoRetargeting = true;
        consensus.nRuleChangeActivationThreshold = 108; // 75% for testchains
        consensus.nMinerConfirmationWindow = 144; // Faster than normal for regtest (144 instead of 2016)
        consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].bit = 28;
        consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nStartTime = 0;
        consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
        consensus.vDeployments[Consensus::DEPLOYMENT_CSV].bit = 0;
        consensus.vDeployments[Consensus::DEPLOYMENT_CSV].nStartTime = 0;
        consensus.vDeployments[Consensus::DEPLOYMENT_CSV].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
        consensus.vDeployments[Consensus::DEPLOYMENT_SEGWIT].bit = 1;
        consensus.vDeployments[Consensus::DEPLOYMENT_SEGWIT].nStartTime = Consensus::BIP9Deployment::ALWAYS_ACTIVE;
        consensus.vDeployments[Consensus::DEPLOYMENT_SEGWIT].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;

        // The best chain should have at least this much work.
        consensus.nMinimumChainWork = uint256S("0x00");

        // By default assume that the signatures in ancestors of this block are valid.
        consensus.defaultAssumeValid = uint256S("0x00");

        pchMessageStart[0] = 0xfa;
        pchMessageStart[1] = 0xbf;
        pchMessageStart[2] = 0xb5;
        pchMessageStart[3] = 0xda;
        nDefaultPort = 19444;
        nPruneAfterHeight = 1000;

        genesis = CreateGenesisBlock(1296688602, 0, 0x207fffff, 1, 50 * COIN);
        consensus.hashGenesisBlock = genesis.GetHash();
        assert(consensus.hashGenesisBlock == uint256S("0x5b2e996d458adbf5c81b381f90ca167732bc9f4e9c1c4ec8485fa74efe793ed8"));
        assert(genesis.hashMerkleRoot == uint256S("0x13ec98c3307b8e6b67b91c605c7347916a99f9dfde7b5d88365aaef322192314"));

        vFixedSeeds.clear(); //!< Regtest mode doesn't have any fixed seeds.
        vSeeds.clear();      //!< Regtest mode doesn't have any DNS seeds.

        fDefaultConsistencyChecks = true;
        fRequireStandard = false;
        fMineBlocksOnDemand = true;

        checkpointData = {
            {
                {0, uint256S("5b2e996d458adbf5c81b381f90ca167732bc9f4e9c1c4ec8485fa74efe793ed8")},
            }
        };

        chainTxData = ChainTxData{
            0,
            0,
            0
        };

        base58Prefixes[PUBKEY_ADDRESS] = std::vector<unsigned char>(1,111);
        base58Prefixes[SCRIPT_ADDRESS] = std::vector<unsigned char>(1,196);
        base58Prefixes[SCRIPT_ADDRESS2] = std::vector<unsigned char>(1,58);
        base58Prefixes[SECRET_KEY] =     std::vector<unsigned char>(1,239);
        base58Prefixes[EXT_PUBLIC_KEY] = {0x04, 0x35, 0x87, 0xCF};
        base58Prefixes[EXT_SECRET_KEY] = {0x04, 0x35, 0x83, 0x94};
        base58Prefixes[KEVA_NAMESPACE] = std::vector<unsigned char>(1,53); // N

        bech32_hrp = "rkva";
    }

    int DefaultCheckKevaDB() const
    {
        return 0;
    }
};

static std::unique_ptr<CChainParams> globalChainParams;

const CChainParams &Params() {
    assert(globalChainParams);
    return *globalChainParams;
}

std::unique_ptr<CChainParams> CreateChainParams(const std::string& chain)
{
    if (chain == CBaseChainParams::MAIN)
        return std::unique_ptr<CChainParams>(new CMainParams());
    else if (chain == CBaseChainParams::TESTNET)
        return std::unique_ptr<CChainParams>(new CTestNetParams());
    else if (chain == CBaseChainParams::REGTEST)
        return std::unique_ptr<CChainParams>(new CRegTestParams());
    throw std::runtime_error(strprintf("%s: Unknown chain %s.", __func__, chain));
}

void SelectParams(const std::string& network)
{
    SelectBaseParams(network);
    globalChainParams = CreateChainParams(network);
}

void UpdateVersionBitsParameters(Consensus::DeploymentPos d, int64_t nStartTime, int64_t nTimeout)
{
    globalChainParams->UpdateVersionBitsParameters(d, nStartTime, nTimeout);
}