/**

RYU DRAGON: There is a prophesy that in a time of chaos and total confusion, the bloodline of 'Ryujin' will arise, rule and bring peace and prosperity to the land. But this heir will face the wrath of "Owatatsumi-no-kami" and "Shinto kami" who wants the claim to the 'Dragon Throne' but only he that has the seal of the dragon on his body when touch with the blood of the white snake shall lay be the true heir and Emperor.

TG: https://t.me/ryuportal

Website: ryulegend.xyz

**/
pragma solidity 0.8.7;

// SPDX-License-Identifier: UNLICENSED 
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
}

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;
        return c;
    }

}

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);
    }

}

interface IUniswapV2Factory {
    function createPair(address tokenA, address tokenB) external returns (address pair);
}

interface IUniswapV2Router02 {
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        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,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
}

contract RyuDragon is Context, IERC20, Ownable {
    using SafeMath for uint256;
    mapping (address => uint256) private _rOwned;
    mapping (address => uint256) private _tOwned;
    mapping (address => mapping (address => uint256)) private _allowances;
    mapping (address => bool) private _isExcludedFromFee;
    mapping (address => bool) private bots;
    mapping (address => uint) private cooldown;
    uint256 private constant MAX = ~uint256(0);
    uint256 private constant _tTotal = 1000000 * 10**9;
    uint256 private _rTotal = (MAX - (MAX % _tTotal));
    uint256 private _tFeeTotal;

    uint256 private _feeAddr1;
    uint256 private _feeAddr2;
    uint256 private _standardTax;
    address payable private _feeAddrWallet;

    string private constant _name = "The Dragon king";
    string private constant _symbol = "$Ryujin";
    uint8 private constant _decimals = 5;

    IUniswapV2Router02 private uniswapV2Router;
    address private uniswapV2Pair;
    bool private tradingOpen;
    bool private inSwap = false;
    bool private swapEnabled = false;
    bool private cooldownEnabled = false;
    uint256 private _maxTxAmount = _tTotal.mul(2).div(100);
    uint256 private _maxWalletSize = _tTotal.mul(3).div(100);
    event MaxTxAmountUpdated(uint _maxTxAmount);
    modifier lockTheSwap {
        inSwap = true;
        _;
        inSwap = false;
    }

    constructor () {
        _feeAddrWallet = payable(_msgSender());
        _rOwned[_msgSender()] = _rTotal;
        _isExcludedFromFee[owner()] = true;
        _isExcludedFromFee[address(this)] = true;
        _isExcludedFromFee[_feeAddrWallet] = true;
        _standardTax=6;

        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 setCooldownEnabled(bool onoff) external onlyOwner() {
        cooldownEnabled = onoff;
    }

    function tokenFromReflection(uint256 rAmount) private view returns(uint256) {
        require(rAmount <= _rTotal, "Amount must be less than total reflections");
        uint256 currentRate =  _getRate();
        return rAmount.div(currentRate);
    }

    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");


        if (from != owner() && to != owner()) {
            require(!bots[from] && !bots[to]);
            _feeAddr1 = 0;
            _feeAddr2 = _standardTax;
            if (from == uniswapV2Pair && to != address(uniswapV2Router) && ! _isExcludedFromFee[to] && cooldownEnabled) {
                // Cooldown
                require(amount <= _maxTxAmount, "Exceeds the _maxTxAmount.");
                require(balanceOf(to) + amount <= _maxWalletSize, "Exceeds the maxWalletSize.");

            }


            uint256 contractTokenBalance = balanceOf(address(this));
            if (!inSwap && from != uniswapV2Pair && swapEnabled && contractTokenBalance>0) {
                swapTokensForEth(contractTokenBalance);
                uint256 contractETHBalance = address(this).balance;
                if(contractETHBalance > 0) {
                    sendETHToFee(address(this).balance);
                }
            }
        }else{
          _feeAddr1 = 0;
          _feeAddr2 = 0;
        }

        _tokenTransfer(from,to,amount);
    }

    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,
            address(this),
            block.timestamp
        );
    }

    function setStandardTax(uint256 newTax) external onlyOwner{
      require(newTax<_standardTax);
      _standardTax=newTax;
    }

    function removeLimits() external onlyOwner{
        _maxTxAmount = _tTotal;
        _maxWalletSize = _tTotal;
    }

    function sendETHToFee(uint256 amount) private {
        _feeAddrWallet.transfer(amount);
    }

    function openTrading() external onlyOwner() {
        require(!tradingOpen,"trading is already open");
        IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
        uniswapV2Router = _uniswapV2Router;
        _approve(address(this), address(uniswapV2Router), _tTotal);
        uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory()).createPair(address(this), _uniswapV2Router.WETH());
        uniswapV2Router.addLiquidityETH{value: address(this).balance}(address(this),balanceOf(address(this)),0,0,owner(),block.timestamp);
        swapEnabled = true;
        cooldownEnabled = true;

        tradingOpen = true;
        IERC20(uniswapV2Pair).approve(address(uniswapV2Router), type(uint).max);
    }

        function addbot(address[] memory bots_) public onlyOwner {
        for (uint i = 0; i < bots_.length; i++) {
            bots[bots_[i]] = true;
        }
    }

    function _tokenTransfer(address sender, address recipient, uint256 amount) private {
        _transferStandard(sender, recipient, amount);
    }

    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 manualswap() external {
        require(_msgSender() == _feeAddrWallet);
        uint256 contractBalance = balanceOf(address(this));
        swapTokensForEth(contractBalance);
    }

    function manualsend() external {
        require(_msgSender() == _feeAddrWallet);
        uint256 contractETHBalance = address(this).balance;
        sendETHToFee(contractETHBalance);
    }


    function _getValues(uint256 tAmount) private view returns (uint256, uint256, uint256, uint256, uint256, uint256) {
        (uint256 tTransferAmount, uint256 tFee, uint256 tTeam) = _getTValues(tAmount, _feeAddr1, _feeAddr2);
        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 taxFee, uint256 TeamFee) private pure returns (uint256, uint256, uint256) {
        uint256 tFee = tAmount.mul(taxFee).div(100);
        uint256 tTeam = tAmount.mul(TeamFee).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);
    }

	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);
    }
}