// File: contracts/PigFinance.sol



/**
   #PIG
   
   #LIQ+#RFI+#SHIB+#DOGE, combine together to #PIG  

    I make this #PIG to hand over it to the community.
    Create the community by yourself if you are interested.   

   Great features:
    1. 4% marketing - on every transfer we take out 4% of the trade, convert tokens to native (BNB) and deliver to marketing address
    2. 3% liquidity - on every transfer we take out 3% of the trade, convert half to native (BNB) and provide liquidity in your primary liquidity pool
    3. 3% burn - on every transfer we take out 3% of the trade and send those tokens directly to the burn address.
    4. 3% reflections - holders redistribution on every transfer we take out 3% of the trade and send those pigVerse directly to the holders.

   I will burn liquidity LPs to burn addresses to lock the pool forever.
   I will renounce the ownership to burn addresses to transfer #PIG to the community, make sure it's 100% safe.

   1,000,000,000,000,000 total supply

   3% fee for liquidity will go to an address that the contract creates, 
   and the contract will sell it and add to liquidity automatically, 
   it's the best part of the #PIG idea, increasing the liquidity pool automatically, 
   help the pool grow from the small init pool.
**/

// SPDX-License-Identifier: Unlicensed
pragma solidity ^0.8.4;

import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import '@openzeppelin/contracts/utils/math/SafeMath.sol';
import '@openzeppelin/contracts/access/Ownable.sol';
import '@openzeppelin/contracts/utils/Address.sol';
import '@uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol';
import '@uniswap/v2-core/contracts/interfaces/IUniswapV2Pair.sol';
import '@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol';

contract PigFinance is Context, IERC20, Ownable {
  using SafeMath for uint256;
  using Address for address;

  address payable public marketingWallet =
    payable(0x2a5a481b1A90abD076e37037dAFC49A67cCb3B7f);
  address public constant deadAddress =
    0x000000000000000000000000000000000000dEaD;

  mapping(address => uint256) private _rOwned;
  mapping(address => uint256) private _tOwned;
  mapping(address => mapping(address => uint256)) private _allowances;
  mapping(address => bool) private _isSniper;
  address[] private _confirmedSnipers;

  mapping(address => bool) private _isExcludedFee;
  mapping(address => bool) private _isExcludedReward;
  address[] private _excluded;

  string private constant _name = 'Pig Finance';
  string private constant _symbol = 'PIG';
  uint8 private constant _decimals = 9;

  uint256 private constant MAX = ~uint256(0);
  uint256 private constant _tTotal = 10**15 * 10**_decimals;
  uint256 private _rTotal = (MAX - (MAX % _tTotal));
  uint256 private _tFeeTotal;

  uint256 public reflectionFee = 3;
  uint256 private _previousReflectFee = reflectionFee;

  uint256 public marketingFee = 4;
  uint256 private _previousMarketingFee = marketingFee;

  uint256 public burnFee = 3;
  uint256 private _previousBurnFee = burnFee;

  uint256 public lpFee = 3;
  uint256 private _previousLpFee = lpFee;

  uint256 public feeRate = 2;
  uint256 public launchTime;

  IUniswapV2Router02 public uniswapV2Router;
  address public uniswapV2Pair;

  // PancakeSwap: 0x10ED43C718714eb63d5aA57B78B54704E256024E
  // Uniswap V2: 0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D
  address private constant _uniswapRouterAddress =
    0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D;

  bool private _inSwapAndLiquify;
  bool private _tradingOpen = false;

  event AddLiquidity(uint256 amountTokens, uint256 amountETH);
  event Send_previousBurnFeewards(address to, uint256 amountETH);
  event SendTokenRewards(address to, address token, uint256 amount);
  event SwapTokensForETH(uint256 amountIn, address[] path);
  event SwapAndLiquify(
    uint256 tokensSwappedForEth,
    uint256 ethAddedForLp,
    uint256 tokensAddedForLp
  );

  modifier lockTheSwap() {
    _inSwapAndLiquify = true;
    _;
    _inSwapAndLiquify = false;
  }

  constructor() {
    _rOwned[_msgSender()] = _rTotal;
    emit Transfer(address(0), _msgSender(), _tTotal);
  }

  function initContract() external onlyOwner {
    IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(
      _uniswapRouterAddress
    );
    uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory()).createPair(
      address(this),
      _uniswapV2Router.WETH()
    );

    uniswapV2Router = _uniswapV2Router;

    _isExcludedFee[owner()] = true;
    _isExcludedFee[address(this)] = true;
  }

  function openTrading() external onlyOwner {
    marketingFee = _previousMarketingFee;
    burnFee = _previousBurnFee;
    reflectionFee = _previousReflectFee;
    lpFee = _previousLpFee;
    _tradingOpen = true;
    launchTime = block.timestamp;
  }

  function name() external pure returns (string memory) {
    return _name;
  }

  function symbol() external pure returns (string memory) {
    return _symbol;
  }

  function decimals() external pure returns (uint8) {
    return _decimals;
  }

  function totalSupply() external pure override returns (uint256) {
    return _tTotal;
  }

  function balanceOf(address account) public view override returns (uint256) {
    if (_isExcludedReward[account]) return _tOwned[account];
    return tokenFromReflection(_rOwned[account]);
  }

  function transfer(address recipient, uint256 amount)
    external
    override
    returns (bool)
  {
    _transfer(_msgSender(), recipient, amount);
    return true;
  }

  function allowance(address owner, address spender)
    external
    view
    override
    returns (uint256)
  {
    return _allowances[owner][spender];
  }

  function approve(address spender, uint256 amount)
    external
    override
    returns (bool)
  {
    _approve(_msgSender(), spender, amount);
    return true;
  }

  function transferFrom(
    address sender,
    address recipient,
    uint256 amount
  ) external override returns (bool) {
    _transfer(sender, recipient, amount);
    _approve(
      sender,
      _msgSender(),
      _allowances[sender][_msgSender()].sub(
        amount,
        'ERC20: transfer amount exceeds allowance'
      )
    );
    return true;
  }

  function increaseAllowance(address spender, uint256 addedValue)
    external
    virtual
    returns (bool)
  {
    _approve(
      _msgSender(),
      spender,
      _allowances[_msgSender()][spender].add(addedValue)
    );
    return true;
  }

  function decreaseAllowance(address spender, uint256 subtractedValue)
    external
    virtual
    returns (bool)
  {
    _approve(
      _msgSender(),
      spender,
      _allowances[_msgSender()][spender].sub(
        subtractedValue,
        'ERC20: decreased allowance below zero'
      )
    );
    return true;
  }

  function totalFees() external view returns (uint256) {
    return _tFeeTotal;
  }

  function deliver(uint256 tAmount) external {
    address sender = _msgSender();
    require(
      !_isExcludedReward[sender],
      'Excluded addresses cannot call this function'
    );
    (uint256 rAmount, , , , , , ) = _getValues(tAmount);
    _rOwned[sender] = _rOwned[sender].sub(rAmount);
    _rTotal = _rTotal.sub(rAmount);
    _tFeeTotal = _tFeeTotal.add(tAmount);
  }

  function reflectionFromToken(uint256 tAmount, bool deductTransferFee)
    external
    view
    returns (uint256)
  {
    require(tAmount <= _tTotal, 'Amount must be less than supply');
    if (!deductTransferFee) {
      (uint256 rAmount, , , , , , ) = _getValues(tAmount);
      return rAmount;
    } else {
      (, uint256 rTransferAmount, , , , , ) = _getValues(tAmount);
      return rTransferAmount;
    }
  }

  function tokenFromReflection(uint256 rAmount) public view returns (uint256) {
    require(rAmount <= _rTotal, 'Amount must be less than total reflections');
    uint256 currentRate = _getRate();
    return rAmount.div(currentRate);
  }

  function excludeFromReward(address account) external onlyOwner {
    require(!_isExcludedReward[account], 'Account is already excluded');
    if (_rOwned[account] > 0) {
      _tOwned[account] = tokenFromReflection(_rOwned[account]);
    }
    _isExcludedReward[account] = true;
    _excluded.push(account);
  }

  function includeInReward(address account) external onlyOwner {
    require(_isExcludedReward[account], 'Account is already included');
    for (uint256 i = 0; i < _excluded.length; i++) {
      if (_excluded[i] == account) {
        _excluded[i] = _excluded[_excluded.length - 1];
        _tOwned[account] = 0;
        _isExcludedReward[account] = false;
        _excluded.pop();
        break;
      }
    }
  }

  function _approve(
    address owner,
    address spender,
    uint256 amount
  ) private {
    require(owner != address(0), 'ERC20: approve from the zero address');
    require(spender != address(0), 'ERC20: approve to the zero address');

    _allowances[owner][spender] = amount;
    emit Approval(owner, spender, amount);
  }

  function _transfer(
    address from,
    address to,
    uint256 amount
  ) private {
    require(from != address(0), 'ERC20: transfer from the zero address');
    require(to != address(0), 'ERC20: transfer to the zero address');
    require(amount > 0, 'Transfer amount must be greater than zero');
    require(!_isSniper[to], 'Stop sniping!');
    require(!_isSniper[from], 'Stop sniping!');
    require(!_isSniper[_msgSender()], 'Stop sniping!');

    bool excludedFromFee = _isExcludedFee[from] || _isExcludedFee[to];

    // buy
    if (from == uniswapV2Pair && to != address(uniswapV2Router)) {
      require(_tradingOpen, 'trading is not open yet');
    }

    // sell
    if (!_inSwapAndLiquify && _tradingOpen && to == uniswapV2Pair) {
      uint256 _contractTokenBalance = balanceOf(address(this));
      if (_contractTokenBalance > 0) {
        if (
          _contractTokenBalance > balanceOf(uniswapV2Pair).mul(feeRate).div(100)
        ) {
          _contractTokenBalance = balanceOf(uniswapV2Pair).mul(feeRate).div(
            100
          );
        }
        _swapTokens(_contractTokenBalance);
      }
    }

    bool takeFee = true;
    if (excludedFromFee) {
      takeFee = false;
    }

    _tokenTransfer(from, to, amount, takeFee);
  }

  function _swapTokens(uint256 _contractTokenBalance) private lockTheSwap {
    uint256 ethBalanceBefore = address(this).balance;
    uint256 _liquidityFeeTotal = _liquidityFeeAggregate();

    // Leave half of LP tokens from total contract balance to be used to add liquidity to Uniswap
    uint256 ethSwapTokens = _contractTokenBalance
      .mul(_liquidityFeeTotal.sub(lpFee))
      .div(_liquidityFeeTotal);
    uint256 lpTokens = _contractTokenBalance.sub(ethSwapTokens);

    _swapTokensForEth(ethSwapTokens);
    uint256 ethBalanceAfter = address(this).balance;
    uint256 ethBalanceUpdate = ethBalanceAfter.sub(ethBalanceBefore);

    // send ETH to marketing address
    uint256 marketingETHBalance = ethBalanceUpdate.mul(marketingFee).div(
      _liquidityFeeTotal
    );
    if (marketingETHBalance > 0) {
      _sendETHToMarketing(marketingETHBalance);
    }

    // add to liquidity pool
    uint256 lpETHBalance = ethBalanceUpdate.sub(marketingETHBalance);
    if (lpETHBalance > 0) {
      _addLp(lpTokens, lpETHBalance);
    }
  }

  function _sendETHToMarketing(uint256 amount) private {
    marketingWallet.call{ value: amount }('');
  }

  function _addLp(uint256 tokenAmount, uint256 ethAmount) private {
    // approve token transfer to cover all possible scenarios
    _approve(address(this), address(uniswapV2Router), tokenAmount);

    // add the liquidity
    uniswapV2Router.addLiquidityETH{ value: ethAmount }(
      address(this),
      tokenAmount,
      0, // slippage is unavoidable
      0, // slippage is unavoidable
      deadAddress,
      block.timestamp
    );
    emit AddLiquidity(tokenAmount, ethAmount);
  }

  function _swapTokensForEth(uint256 tokenAmount) private {
    // generate the uniswap pair path of token -> weth
    address[] memory path = new address[](2);
    path[0] = address(this);
    path[1] = uniswapV2Router.WETH();

    _approve(address(this), address(uniswapV2Router), tokenAmount);

    // make the swap
    uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
      tokenAmount,
      0, // accept any amount of ETH
      path,
      address(this), // the contract
      block.timestamp
    );

    emit SwapTokensForETH(tokenAmount, path);
  }

  function _tokenTransfer(
    address sender,
    address recipient,
    uint256 amount,
    bool takeFee
  ) private {
    if (!takeFee) _removeAllFee();

    if (_isExcludedReward[sender] && !_isExcludedReward[recipient]) {
      _transferFromExcluded(sender, recipient, amount);
    } else if (!_isExcludedReward[sender] && _isExcludedReward[recipient]) {
      _transferToExcluded(sender, recipient, amount);
    } else if (_isExcludedReward[sender] && _isExcludedReward[recipient]) {
      _transferBothExcluded(sender, recipient, amount);
    } else {
      _transferStandard(sender, recipient, amount);
    }

    if (!takeFee) _restoreAllFee();
  }

  function _transferStandard(
    address sender,
    address recipient,
    uint256 tAmount
  ) private {
    (
      uint256 rAmount,
      uint256 rTransferAmount,
      uint256 rFee,
      uint256 tTransferAmount,
      uint256 tFee,
      uint256 tLiquidity,
      uint256 tBurn
    ) = _getValues(tAmount);
    _rOwned[sender] = _rOwned[sender].sub(rAmount);
    _rOwned[recipient] = _rOwned[recipient].add(rTransferAmount);
    _takeLiquidity(tLiquidity);
    _takeBurn(tBurn);
    _reflectFee(rFee, tFee);
    emit Transfer(sender, recipient, tTransferAmount);
  }

  function _transferToExcluded(
    address sender,
    address recipient,
    uint256 tAmount
  ) private {
    (
      uint256 rAmount,
      uint256 rTransferAmount,
      uint256 rFee,
      uint256 tTransferAmount,
      uint256 tFee,
      uint256 tLiquidity,
      uint256 tBurn
    ) = _getValues(tAmount);
    _rOwned[sender] = _rOwned[sender].sub(rAmount);
    _tOwned[recipient] = _tOwned[recipient].add(tTransferAmount);
    _rOwned[recipient] = _rOwned[recipient].add(rTransferAmount);
    _takeLiquidity(tLiquidity);
    _takeBurn(tBurn);
    _reflectFee(rFee, tFee);
    emit Transfer(sender, recipient, tTransferAmount);
  }

  function _transferFromExcluded(
    address sender,
    address recipient,
    uint256 tAmount
  ) private {
    (
      uint256 rAmount,
      uint256 rTransferAmount,
      uint256 rFee,
      uint256 tTransferAmount,
      uint256 tFee,
      uint256 tLiquidity,
      uint256 tBurn
    ) = _getValues(tAmount);
    _tOwned[sender] = _tOwned[sender].sub(tAmount);
    _rOwned[sender] = _rOwned[sender].sub(rAmount);
    _rOwned[recipient] = _rOwned[recipient].add(rTransferAmount);
    _takeLiquidity(tLiquidity);
    _takeBurn(tBurn);
    _reflectFee(rFee, tFee);
    emit Transfer(sender, recipient, tTransferAmount);
  }

  function _transferBothExcluded(
    address sender,
    address recipient,
    uint256 tAmount
  ) private {
    (
      uint256 rAmount,
      uint256 rTransferAmount,
      uint256 rFee,
      uint256 tTransferAmount,
      uint256 tFee,
      uint256 tLiquidity,
      uint256 tBurn
    ) = _getValues(tAmount);
    _tOwned[sender] = _tOwned[sender].sub(tAmount);
    _rOwned[sender] = _rOwned[sender].sub(rAmount);
    _tOwned[recipient] = _tOwned[recipient].add(tTransferAmount);
    _rOwned[recipient] = _rOwned[recipient].add(rTransferAmount);
    _takeLiquidity(tLiquidity);
    _takeBurn(tBurn);
    _reflectFee(rFee, tFee);
    emit Transfer(sender, recipient, tTransferAmount);
  }

  function _reflectFee(uint256 rFee, uint256 tFee) private {
    _rTotal = _rTotal.sub(rFee);
    _tFeeTotal = _tFeeTotal.add(tFee);
  }

  function _getValues(uint256 tAmount)
    private
    view
    returns (
      uint256,
      uint256,
      uint256,
      uint256,
      uint256,
      uint256,
      uint256
    )
  {
    (
      uint256 tTransferAmount,
      uint256 tFee,
      uint256 tLiquidity,
      uint256 tBurn
    ) = _getTValues(tAmount);
    (uint256 rAmount, uint256 rTransferAmount, uint256 rFee) = _getRValues(
      tAmount,
      tFee,
      tLiquidity,
      tBurn,
      _getRate()
    );
    return (
      rAmount,
      rTransferAmount,
      rFee,
      tTransferAmount,
      tFee,
      tLiquidity,
      tBurn
    );
  }

  function _getTValues(uint256 tAmount)
    private
    view
    returns (
      uint256,
      uint256,
      uint256,
      uint256
    )
  {
    uint256 tFee = _calculateReflectFee(tAmount);
    uint256 tLiquidity = _calculateLiquidityFee(tAmount);
    uint256 tBurn = _calculateBurnFee(tAmount);
    uint256 tTransferAmount = tAmount.sub(tFee).sub(tLiquidity).sub(tBurn);
    return (tTransferAmount, tFee, tLiquidity, tBurn);
  }

  function _getRValues(
    uint256 tAmount,
    uint256 tFee,
    uint256 tLiquidity,
    uint256 tBurn,
    uint256 currentRate
  )
    private
    pure
    returns (
      uint256,
      uint256,
      uint256
    )
  {
    uint256 rAmount = tAmount.mul(currentRate);
    uint256 rFee = tFee.mul(currentRate);
    uint256 rLiquidity = tLiquidity.mul(currentRate);
    uint256 rBurn = tBurn.mul(currentRate);
    uint256 rTransferAmount = rAmount.sub(rFee).sub(rLiquidity).sub(rBurn);
    return (rAmount, rTransferAmount, rFee);
  }

  function _getRate() private view returns (uint256) {
    (uint256 rSupply, uint256 tSupply) = _getCurrentSupply();
    return rSupply.div(tSupply);
  }

  function _getCurrentSupply() private view returns (uint256, uint256) {
    uint256 rSupply = _rTotal;
    uint256 tSupply = _tTotal;
    for (uint256 i = 0; i < _excluded.length; i++) {
      if (_rOwned[_excluded[i]] > rSupply || _tOwned[_excluded[i]] > tSupply)
        return (_rTotal, _tTotal);
      rSupply = rSupply.sub(_rOwned[_excluded[i]]);
      tSupply = tSupply.sub(_tOwned[_excluded[i]]);
    }
    if (rSupply < _rTotal.div(_tTotal)) return (_rTotal, _tTotal);
    return (rSupply, tSupply);
  }

  function _takeLiquidity(uint256 tLiquidity) private {
    uint256 currentRate = _getRate();
    uint256 rLiquidity = tLiquidity.mul(currentRate);
    _rOwned[address(this)] = _rOwned[address(this)].add(rLiquidity);
    if (_isExcludedReward[address(this)])
      _tOwned[address(this)] = _tOwned[address(this)].add(tLiquidity);
  }

  function _takeBurn(uint256 tBurn) private {
    uint256 currentRate = _getRate();
    uint256 rBurn = tBurn.mul(currentRate);
    _rOwned[deadAddress] = _rOwned[deadAddress].add(rBurn);
    if (_isExcludedReward[deadAddress])
      _tOwned[deadAddress] = _tOwned[deadAddress].add(tBurn);
  }

  function _calculateReflectFee(uint256 _amount)
    private
    view
    returns (uint256)
  {
    return _amount.mul(reflectionFee).div(10**2);
  }

  function _calculateLiquidityFee(uint256 _amount)
    private
    view
    returns (uint256)
  {
    return _amount.mul(_liquidityFeeAggregate()).div(10**2);
  }

  function _calculateBurnFee(uint256 _amount) private view returns (uint256) {
    return _amount.mul(burnFee).div(10**2);
  }

  function _liquidityFeeAggregate() private view returns (uint256) {
    return marketingFee.add(lpFee);
  }

  function _removeAllFee() private {
    if (reflectionFee == 0 && marketingFee == 0 && burnFee == 0 && lpFee == 0)
      return;

    _previousReflectFee = reflectionFee;
    _previousMarketingFee = marketingFee;
    _previousBurnFee = burnFee;
    _previousLpFee = lpFee;

    reflectionFee = 0;
    marketingFee = 0;
    burnFee = 0;
    lpFee = 0;
  }

  function _restoreAllFee() private {
    reflectionFee = _previousReflectFee;
    marketingFee = _previousMarketingFee;
    burnFee = _previousBurnFee;
    lpFee = _previousLpFee;
  }

  function isExcludedFromReward(address account) external view returns (bool) {
    return _isExcludedReward[account];
  }

  function excludeFromFee(address account) external onlyOwner {
    _isExcludedFee[account] = true;
  }

  function includeInFee(address account) external onlyOwner {
    _isExcludedFee[account] = false;
  }

  function setReflectionFeePercent(uint256 _newFee) external onlyOwner {
    require(_newFee <= 10, 'fee cannot exceed 10%');
    reflectionFee = _newFee;
  }

  function setMarketingFeePercent(uint256 _newFee) external onlyOwner {
    require(_newFee <= 10, 'fee cannot exceed 10%');
    marketingFee = _newFee;
  }

  function setBurnFeePercent(uint256 _newFee) external onlyOwner {
    require(_newFee <= 10, 'fee cannot exceed 10%');
    burnFee = _newFee;
  }

  function setLpFeePercent(uint256 _newFee) external onlyOwner {
    require(_newFee <= 10, 'fee cannot exceed 10%');
    lpFee = _newFee;
  }

  function setMarketingAddress(address _marketingWallet) external onlyOwner {
    marketingWallet = payable(_marketingWallet);
  }

  function isRemovedSniper(address account) external view returns (bool) {
    return _isSniper[account];
  }

  function removeSniper(address account) external onlyOwner {
    require(account != _uniswapRouterAddress, 'We can not blacklist Uniswap');
    require(!_isSniper[account], 'Account is already blacklisted');
    _isSniper[account] = true;
    _confirmedSnipers.push(account);
  }

  function amnestySniper(address account) external onlyOwner {
    require(_isSniper[account], 'Account is not blacklisted');
    for (uint256 i = 0; i < _confirmedSnipers.length; i++) {
      if (_confirmedSnipers[i] == account) {
        _confirmedSnipers[i] = _confirmedSnipers[_confirmedSnipers.length - 1];
        _isSniper[account] = false;
        _confirmedSnipers.pop();
        break;
      }
    }
  }

  function setFeeRate(uint256 _rate) external onlyOwner {
    feeRate = _rate;
  }

  function emergencyWithdraw() external onlyOwner {
    payable(owner()).call{ value: address(this).balance }('');
  }

  // to recieve ETH from uniswapV2Router when swaping
  receive() external payable {}
}

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

// File: @openzeppelin/contracts/utils/math/SafeMath.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.

/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is no longer needed starting with Solidity 0.8. The compiler
 * now has built in overflow checking.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        return a + b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return a - b;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        return a * b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b <= a, errorMessage);
            return a - b;
        }
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}

// File: @openzeppelin/contracts/access/Ownable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "../utils/Context.sol";

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _setOwner(_msgSender());
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _setOwner(address(0));
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _setOwner(newOwner);
    }

    function _setOwner(address newOwner) private {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

// File: @openzeppelin/contracts/utils/Address.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        assembly {
            size := extcodesize(account)
        }
        return size > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");

        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    function _verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) private pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

// File: @uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol



pragma solidity >=0.5.0;

interface IUniswapV2Factory {
    event PairCreated(address indexed token0, address indexed token1, address pair, uint);

    function feeTo() external view returns (address);
    function feeToSetter() external view returns (address);

    function getPair(address tokenA, address tokenB) external view returns (address pair);
    function allPairs(uint) external view returns (address pair);
    function allPairsLength() external view returns (uint);

    function createPair(address tokenA, address tokenB) external returns (address pair);

    function setFeeTo(address) external;
    function setFeeToSetter(address) external;
}

// File: @uniswap/v2-core/contracts/interfaces/IUniswapV2Pair.sol



pragma solidity >=0.5.0;

interface IUniswapV2Pair {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);

    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint);

    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;

    event Mint(address indexed sender, uint amount0, uint amount1);
    event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
    event Swap(
        address indexed sender,
        uint amount0In,
        uint amount1In,
        uint amount0Out,
        uint amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);

    function MINIMUM_LIQUIDITY() external pure returns (uint);
    function factory() external view returns (address);
    function token0() external view returns (address);
    function token1() external view returns (address);
    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
    function price0CumulativeLast() external view returns (uint);
    function price1CumulativeLast() external view returns (uint);
    function kLast() external view returns (uint);

    function mint(address to) external returns (uint liquidity);
    function burn(address to) external returns (uint amount0, uint amount1);
    function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
    function skim(address to) external;
    function sync() external;

    function initialize(address, address) external;
}

// File: @uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol



pragma solidity >=0.6.2;

import './IUniswapV2Router01.sol';

interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountETH);
    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountETH);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}

// File: @openzeppelin/contracts/utils/Context.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// File: @uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router01.sol



pragma solidity >=0.6.2;

interface IUniswapV2Router01 {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB, uint liquidity);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountToken, uint amountETH);
    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETHWithPermit(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountToken, uint amountETH);
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);
    function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);

    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
    function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}