// Copyright (c) 2012-2015, The CryptoNote developers, The Bytecoin developers
//
// This file is part of Bytecoin.
//
// Bytecoin is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Bytecoin is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with Bytecoin.  If not, see <http://www.gnu.org/licenses/>.

#include "Currency.h"
#include <cctype>
#include <boost/algorithm/string/trim.hpp>
#include <boost/lexical_cast.hpp>
#include "../Common/Base58.h"
#include "../Common/int-util.h"
#include "../Common/StringTools.h"

#include "Account.h"
#include "CryptoNoteBasicImpl.h"
#include "CryptoNoteFormatUtils.h"
#include "CryptoNoteTools.h"
#include "TransactionExtra.h"
#include "UpgradeDetector.h"

#undef ERROR

using namespace Logging;
using namespace Common;

namespace CryptoNote {

bool Currency::init() {
  if (!generateGenesisBlock()) {
    logger(ERROR, BRIGHT_RED) << "Failed to generate genesis block";
    return false;
  }

  if (!get_block_hash(m_genesisBlock, m_genesisBlockHash)) {
    logger(ERROR, BRIGHT_RED) << "Failed to get genesis block hash";
    return false;
  }

  if (isTestnet()) {
    m_upgradeHeight = 0;
    m_blocksFileName = "testnet_" + m_blocksFileName;
    m_blocksCacheFileName = "testnet_" + m_blocksCacheFileName;
    m_blockIndexesFileName = "testnet_" + m_blockIndexesFileName;
    m_txPoolFileName = "testnet_" + m_txPoolFileName;
    m_blockchinIndicesFileName = "testnet_" + m_blockchinIndicesFileName;
  }

  return true;
}

bool Currency::generateGenesisBlock() {
  m_genesisBlock = boost::value_initialized<Block>();

  //account_public_address ac = boost::value_initialized<AccountPublicAddress>();
  //std::vector<size_t> sz;
  //constructMinerTx(0, 0, 0, 0, 0, ac, m_genesisBlock.baseTransaction); // zero fee in genesis
  //BinaryArray txb = toBinaryArray(m_genesisBlock.baseTransaction);
  //std::string hex_tx_represent = Common::toHex(txb);

  // Hard code coinbase tx in genesis block, because through generating tx use random, but genesis should be always the same
  std::string genesisCoinbaseTxHex = "010a01ff0001ffffffffffff0f029b2e4c0281c0b02e7c53291a94d1d0cbff8883f8024f5142ee494ffbbd08807121013c086a48c15fb637a96991bc6d53caf77068b5ba6eeb3c82357228c49790584a";
  BinaryArray minerTxBlob;

  bool r =
    fromHex(genesisCoinbaseTxHex, minerTxBlob) &&
    fromBinaryArray(m_genesisBlock.baseTransaction, minerTxBlob);

  if (!r) {
    logger(ERROR, BRIGHT_RED) << "failed to parse coinbase tx from hard coded blob";
    return false;
  }

  m_genesisBlock.majorVersion = BLOCK_MAJOR_VERSION_1;
  m_genesisBlock.minorVersion = BLOCK_MINOR_VERSION_0;
  m_genesisBlock.timestamp = 0;
  m_genesisBlock.nonce = 70;
  if (m_testnet) {
    ++m_genesisBlock.nonce;
  }
  //miner::find_nonce_for_given_block(bl, 1, 0);

  return true;
}

bool Currency::getBlockReward(size_t medianSize, size_t currentBlockSize, uint64_t alreadyGeneratedCoins,
  uint64_t fee, bool penalizeFee, uint64_t& reward, int64_t& emissionChange) const {
  assert(alreadyGeneratedCoins <= m_moneySupply);
  assert(m_emissionSpeedFactor > 0 && m_emissionSpeedFactor <= 8 * sizeof(uint64_t));

  uint64_t baseReward = (m_moneySupply - alreadyGeneratedCoins) >> m_emissionSpeedFactor;

  size_t blockGrantedFullRewardZone = penalizeFee ?
  m_blockGrantedFullRewardZone :
                               CryptoNote::parameters::CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V1;
  medianSize = std::max(medianSize, blockGrantedFullRewardZone);
  if (currentBlockSize > UINT64_C(2) * medianSize) {
    logger(TRACE) << "Block cumulative size is too big: " << currentBlockSize << ", expected less than " << 2 * medianSize;
    return false;
  }

  uint64_t penalizedBaseReward = getPenalizedAmount(baseReward, medianSize, currentBlockSize);
  uint64_t penalizedFee = penalizeFee ? getPenalizedAmount(fee, medianSize, currentBlockSize) : fee;

  emissionChange = penalizedBaseReward - (fee - penalizedFee);
  reward = penalizedBaseReward + penalizedFee;

  return true;
}

size_t Currency::maxBlockCumulativeSize(uint64_t height) const {
  assert(height <= std::numeric_limits<uint64_t>::max() / m_maxBlockSizeGrowthSpeedNumerator);
  size_t maxSize = static_cast<size_t>(m_maxBlockSizeInitial +
    (height * m_maxBlockSizeGrowthSpeedNumerator) / m_maxBlockSizeGrowthSpeedDenominator);
  assert(maxSize >= m_maxBlockSizeInitial);
  return maxSize;
}

bool Currency::constructMinerTx(uint32_t height, size_t medianSize, uint64_t alreadyGeneratedCoins, size_t currentBlockSize,
  uint64_t fee, const AccountPublicAddress& minerAddress, Transaction& tx,
  const BinaryArray& extraNonce/* = BinaryArray()*/, size_t maxOuts/* = 1*/,
  bool penalizeFee/* = false*/) const {
  tx.inputs.clear();
  tx.outputs.clear();
  tx.extra.clear();

  KeyPair txkey = generateKeyPair();
  addTransactionPublicKeyToExtra(tx.extra, txkey.publicKey);
  if (!extraNonce.empty()) {
    if (!addExtraNonceToTransactionExtra(tx.extra, extraNonce)) {
      return false;
    }
  }

  BaseInput in;
  in.blockIndex = height;

  uint64_t blockReward;
  int64_t emissionChange;
  if (!getBlockReward(medianSize, currentBlockSize, alreadyGeneratedCoins, fee, penalizeFee, blockReward, emissionChange)) {
    logger(INFO) << "Block is too big";
    return false;
  }

  std::vector<uint64_t> outAmounts;
  decompose_amount_into_digits(blockReward, m_defaultDustThreshold,
    [&outAmounts](uint64_t a_chunk) { outAmounts.push_back(a_chunk); },
    [&outAmounts](uint64_t a_dust) { outAmounts.push_back(a_dust); });

  if (!(1 <= maxOuts)) { logger(ERROR, BRIGHT_RED) << "max_out must be non-zero"; return false; }
  while (maxOuts < outAmounts.size()) {
    outAmounts[outAmounts.size() - 2] += outAmounts.back();
    outAmounts.resize(outAmounts.size() - 1);
  }

  uint64_t summaryAmounts = 0;
  for (size_t no = 0; no < outAmounts.size(); no++) {
    Crypto::KeyDerivation derivation = boost::value_initialized<Crypto::KeyDerivation>();
    Crypto::PublicKey outEphemeralPubKey = boost::value_initialized<Crypto::PublicKey>();

    bool r = Crypto::generate_key_derivation(minerAddress.viewPublicKey, txkey.secretKey, derivation);

    if (!(r)) {
      logger(ERROR, BRIGHT_RED)
        << "while creating outs: failed to generate_key_derivation("
        << minerAddress.viewPublicKey << ", " << txkey.secretKey << ")";
      return false;
    }

    r = Crypto::derive_public_key(derivation, no, minerAddress.spendPublicKey, outEphemeralPubKey);

    if (!(r)) {
      logger(ERROR, BRIGHT_RED)
        << "while creating outs: failed to derive_public_key("
        << derivation << ", " << no << ", "
        << minerAddress.spendPublicKey << ")";
      return false;
    }

    KeyOutput tk;
    tk.key = outEphemeralPubKey;

    TransactionOutput out;
    summaryAmounts += out.amount = outAmounts[no];
    out.target = tk;
    tx.outputs.push_back(out);
  }

  if (!(summaryAmounts == blockReward)) {
    logger(ERROR, BRIGHT_RED) << "Failed to construct miner tx, summaryAmounts = " << summaryAmounts << " not equal blockReward = " << blockReward;
    return false;
  }

  tx.version = CURRENT_TRANSACTION_VERSION;
  //lock
  tx.unlockTime = height + m_minedMoneyUnlockWindow;
  tx.inputs.push_back(in);
  return true;
}

bool Currency::isFusionTransaction(const Transaction& transaction, uint64_t inputAmount, size_t size) const {
  assert(getInputAmount(transaction) == inputAmount);
  assert(getObjectBinarySize(transaction) == size);

  if (size > fusionTxMaxSize()) {
    return false;
  }

  if (transaction.inputs.size() < fusionTxMinInputCount()) {
    return false;
  }

  if (transaction.inputs.size() < transaction.outputs.size() * fusionTxMinInOutCountRatio()) {
    return false;
  }

  std::vector<uint64_t> expectedOutputsAmounts;
  expectedOutputsAmounts.reserve(transaction.outputs.size());
  decomposeAmount(inputAmount, defaultDustThreshold(), expectedOutputsAmounts);
  assert(!expectedOutputsAmounts.empty());

  if (expectedOutputsAmounts.size() != transaction.outputs.size()) {
    return false;
  }

  std::sort(expectedOutputsAmounts.begin(), expectedOutputsAmounts.end());

  if (expectedOutputsAmounts.front() <= defaultDustThreshold()) {
    return false;
  }

  auto it1 = expectedOutputsAmounts.begin();
  auto it2 = transaction.outputs.begin();
  for (; it1 != expectedOutputsAmounts.end(); ++it1, ++it2) {
    if (*it1 != it2->amount) {
      return false;
    }
  }

  return true;
}

bool Currency::isFusionTransaction(const Transaction& transaction) const {
  return isFusionTransaction(transaction, getInputAmount(transaction), getObjectBinarySize(transaction));
}

std::string Currency::accountAddressAsString(const AccountBase& account) const {
  return getAccountAddressAsStr(m_publicAddressBase58Prefix, account.getAccountKeys().address);
}

std::string Currency::accountAddressAsString(const AccountPublicAddress& accountPublicAddress) const {
  return getAccountAddressAsStr(m_publicAddressBase58Prefix, accountPublicAddress);
}

bool Currency::parseAccountAddressString(const std::string& str, AccountPublicAddress& addr) const {
  uint64_t prefix;
  if (!CryptoNote::parseAccountAddressString(prefix, addr, str)) {
    return false;
  }

  if (prefix != m_publicAddressBase58Prefix) {
    logger(DEBUGGING) << "Wrong address prefix: " << prefix << ", expected " << m_publicAddressBase58Prefix;
    return false;
  }

  return true;
}

std::string Currency::formatAmount(uint64_t amount) const {
  std::string s = std::to_string(amount);
  if (s.size() < m_numberOfDecimalPlaces + 1) {
    s.insert(0, m_numberOfDecimalPlaces + 1 - s.size(), '0');
  }
  s.insert(s.size() - m_numberOfDecimalPlaces, ".");
  return s;
}

std::string Currency::formatAmount(int64_t amount) const {
  std::string s = formatAmount(static_cast<uint64_t>(std::abs(amount)));

  if (amount < 0) {
    s.insert(0, "-");
  }

  return s;
}

bool Currency::parseAmount(const std::string& str, uint64_t& amount) const {
  std::string strAmount = str;
  boost::algorithm::trim(strAmount);

  size_t pointIndex = strAmount.find_first_of('.');
  size_t fractionSize;
  if (std::string::npos != pointIndex) {
    fractionSize = strAmount.size() - pointIndex - 1;
    while (m_numberOfDecimalPlaces < fractionSize && '0' == strAmount.back()) {
      strAmount.erase(strAmount.size() - 1, 1);
      --fractionSize;
    }
    if (m_numberOfDecimalPlaces < fractionSize) {
      return false;
    }
    strAmount.erase(pointIndex, 1);
  } else {
    fractionSize = 0;
  }

  if (strAmount.empty()) {
    return false;
  }

  if (!std::all_of(strAmount.begin(), strAmount.end(), ::isdigit)) {
    return false;
  }

  if (fractionSize < m_numberOfDecimalPlaces) {
    strAmount.append(m_numberOfDecimalPlaces - fractionSize, '0');
  }

  return Common::fromString(strAmount, amount);
}

difficulty_type Currency::nextDifficulty(std::vector<uint64_t> timestamps,
  std::vector<difficulty_type> cumulativeDifficulties) const {
  assert(m_difficultyWindow >= 2);

  if (timestamps.size() > m_difficultyWindow) {
    timestamps.resize(m_difficultyWindow);
    cumulativeDifficulties.resize(m_difficultyWindow);
  }

  size_t length = timestamps.size();
  assert(length == cumulativeDifficulties.size());
  assert(length <= m_difficultyWindow);
  if (length <= 1) {
    return 1;
  }

  sort(timestamps.begin(), timestamps.end());

  size_t cutBegin, cutEnd;
  assert(2 * m_difficultyCut <= m_difficultyWindow - 2);
  if (length <= m_difficultyWindow - 2 * m_difficultyCut) {
    cutBegin = 0;
    cutEnd = length;
  } else {
    cutBegin = (length - (m_difficultyWindow - 2 * m_difficultyCut) + 1) / 2;
    cutEnd = cutBegin + (m_difficultyWindow - 2 * m_difficultyCut);
  }
  assert(/*cut_begin >= 0 &&*/ cutBegin + 2 <= cutEnd && cutEnd <= length);
  uint64_t timeSpan = timestamps[cutEnd - 1] - timestamps[cutBegin];
  if (timeSpan == 0) {
    timeSpan = 1;
  }

  difficulty_type totalWork = cumulativeDifficulties[cutEnd - 1] - cumulativeDifficulties[cutBegin];
  assert(totalWork > 0);

  uint64_t low, high;
  low = mul128(totalWork, m_difficultyTarget, &high);
  if (high != 0 || low + timeSpan - 1 < low) {
    return 0;
  }

  return (low + timeSpan - 1) / timeSpan;
}

bool Currency::checkProofOfWorkV1(Crypto::cn_context& context, const Block& block, difficulty_type currentDiffic,
  Crypto::Hash& proofOfWork) const {
  if (BLOCK_MAJOR_VERSION_1 != block.majorVersion) {
    return false;
  }

  if (!get_block_longhash(context, block, proofOfWork)) {
    return false;
  }

  return check_hash(proofOfWork, currentDiffic);
}

bool Currency::checkProofOfWorkV2(Crypto::cn_context& context, const Block& block, difficulty_type currentDiffic,
  Crypto::Hash& proofOfWork) const {
  if (BLOCK_MAJOR_VERSION_2 != block.majorVersion) {
    return false;
  }

  if (!get_block_longhash(context, block, proofOfWork)) {
    return false;
  }

  if (!check_hash(proofOfWork, currentDiffic)) {
    return false;
  }

  TransactionExtraMergeMiningTag mmTag;
  if (!getMergeMiningTagFromExtra(block.parentBlock.baseTransaction.extra, mmTag)) {
    logger(ERROR) << "merge mining tag wasn't found in extra of the parent block miner transaction";
    return false;
  }

  if (8 * sizeof(m_genesisBlockHash) < block.parentBlock.blockchainBranch.size()) {
    return false;
  }

  Crypto::Hash auxBlockHeaderHash;
  if (!get_aux_block_header_hash(block, auxBlockHeaderHash)) {
    return false;
  }

  Crypto::Hash auxBlocksMerkleRoot;
  Crypto::tree_hash_from_branch(block.parentBlock.blockchainBranch.data(), block.parentBlock.blockchainBranch.size(),
    auxBlockHeaderHash, &m_genesisBlockHash, auxBlocksMerkleRoot);

  if (auxBlocksMerkleRoot != mmTag.merkleRoot) {
    logger(ERROR, BRIGHT_YELLOW) << "Aux block hash wasn't found in merkle tree";
    return false;
  }

  return true;
}

bool Currency::checkProofOfWork(Crypto::cn_context& context, const Block& block, difficulty_type currentDiffic, Crypto::Hash& proofOfWork) const {
  switch (block.majorVersion) {
  case BLOCK_MAJOR_VERSION_1: return checkProofOfWorkV1(context, block, currentDiffic, proofOfWork);
  case BLOCK_MAJOR_VERSION_2: return checkProofOfWorkV2(context, block, currentDiffic, proofOfWork);
  }

  logger(ERROR, BRIGHT_RED) << "Unknown block major version: " << block.majorVersion << "." << block.minorVersion;
  return false;
}

CurrencyBuilder::CurrencyBuilder(Logging::ILogger& log) : m_currency(log) {
  maxBlockNumber(parameters::CRYPTONOTE_MAX_BLOCK_NUMBER);
  maxBlockBlobSize(parameters::CRYPTONOTE_MAX_BLOCK_BLOB_SIZE);
  maxTxSize(parameters::CRYPTONOTE_MAX_TX_SIZE);
  publicAddressBase58Prefix(parameters::CRYPTONOTE_PUBLIC_ADDRESS_BASE58_PREFIX);
  minedMoneyUnlockWindow(parameters::CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW);

  timestampCheckWindow(parameters::BLOCKCHAIN_TIMESTAMP_CHECK_WINDOW);
  blockFutureTimeLimit(parameters::CRYPTONOTE_BLOCK_FUTURE_TIME_LIMIT);

  moneySupply(parameters::MONEY_SUPPLY);
  emissionSpeedFactor(parameters::EMISSION_SPEED_FACTOR);

  rewardBlocksWindow(parameters::CRYPTONOTE_REWARD_BLOCKS_WINDOW);
  blockGrantedFullRewardZone(parameters::CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE);
  minerTxBlobReservedSize(parameters::CRYPTONOTE_COINBASE_BLOB_RESERVED_SIZE);

  numberOfDecimalPlaces(parameters::CRYPTONOTE_DISPLAY_DECIMAL_POINT);

  mininumFee(parameters::MINIMUM_FEE);
  defaultDustThreshold(parameters::DEFAULT_DUST_THRESHOLD);

  difficultyTarget(parameters::DIFFICULTY_TARGET);
  difficultyWindow(parameters::DIFFICULTY_WINDOW);
  difficultyLag(parameters::DIFFICULTY_LAG);
  difficultyCut(parameters::DIFFICULTY_CUT);

  maxBlockSizeInitial(parameters::MAX_BLOCK_SIZE_INITIAL);
  maxBlockSizeGrowthSpeedNumerator(parameters::MAX_BLOCK_SIZE_GROWTH_SPEED_NUMERATOR);
  maxBlockSizeGrowthSpeedDenominator(parameters::MAX_BLOCK_SIZE_GROWTH_SPEED_DENOMINATOR);

  lockedTxAllowedDeltaSeconds(parameters::CRYPTONOTE_LOCKED_TX_ALLOWED_DELTA_SECONDS);
  lockedTxAllowedDeltaBlocks(parameters::CRYPTONOTE_LOCKED_TX_ALLOWED_DELTA_BLOCKS);

  mempoolTxLiveTime(parameters::CRYPTONOTE_MEMPOOL_TX_LIVETIME);
  mempoolTxFromAltBlockLiveTime(parameters::CRYPTONOTE_MEMPOOL_TX_FROM_ALT_BLOCK_LIVETIME);
  numberOfPeriodsToForgetTxDeletedFromPool(parameters::CRYPTONOTE_NUMBER_OF_PERIODS_TO_FORGET_TX_DELETED_FROM_POOL);

  fusionTxMaxSize(parameters::FUSION_TX_MAX_SIZE);
  fusionTxMinInputCount(parameters::FUSION_TX_MIN_INPUT_COUNT);
  fusionTxMinInOutCountRatio(parameters::FUSION_TX_MIN_IN_OUT_COUNT_RATIO);

  upgradeHeight(parameters::UPGRADE_HEIGHT);
  upgradeVotingThreshold(parameters::UPGRADE_VOTING_THRESHOLD);
  upgradeVotingWindow(parameters::UPGRADE_VOTING_WINDOW);
  upgradeWindow(parameters::UPGRADE_WINDOW);

  blocksFileName(parameters::CRYPTONOTE_BLOCKS_FILENAME);
  blocksCacheFileName(parameters::CRYPTONOTE_BLOCKSCACHE_FILENAME);
  blockIndexesFileName(parameters::CRYPTONOTE_BLOCKINDEXES_FILENAME);
  txPoolFileName(parameters::CRYPTONOTE_POOLDATA_FILENAME);
  blockchinIndicesFileName(parameters::CRYPTONOTE_BLOCKCHAIN_INDICES_FILENAME);

  testnet(false);
}

CurrencyBuilder& CurrencyBuilder::emissionSpeedFactor(unsigned int val) {
  if (val <= 0 || val > 8 * sizeof(uint64_t)) {
    throw std::invalid_argument("val at emissionSpeedFactor()");
  }

  m_currency.m_emissionSpeedFactor = val;
  return *this;
}

CurrencyBuilder& CurrencyBuilder::numberOfDecimalPlaces(size_t val) {
  m_currency.m_numberOfDecimalPlaces = val;
  m_currency.m_coin = 1;
  for (size_t i = 0; i < m_currency.m_numberOfDecimalPlaces; ++i) {
    m_currency.m_coin *= 10;
  }

  return *this;
}

CurrencyBuilder& CurrencyBuilder::difficultyWindow(size_t val) {
  if (val < 2) {
    throw std::invalid_argument("val at difficultyWindow()");
  }
  m_currency.m_difficultyWindow = val;
  return *this;
}

CurrencyBuilder& CurrencyBuilder::upgradeVotingThreshold(unsigned int val) {
  if (val <= 0 || val > 100) {
    throw std::invalid_argument("val at upgradeVotingThreshold()");
  }

  m_currency.m_upgradeVotingThreshold = val;
  return *this;
}

CurrencyBuilder& CurrencyBuilder::upgradeWindow(size_t val) {
  if (val <= 0) {
    throw std::invalid_argument("val at upgradeWindow()");
  }

  m_currency.m_upgradeWindow = val;
  return *this;
}

}