/**

Urashima Taro is a fisherman who is rewarded with a trip under the sea to visit the Kingdom of the Dragon God after rescuing a turtle. 
The princess gave a box to Urashima Taro and asked him not to open the box so that he could always live happily. However, Urashima Taro 
who was curious about the contents of the box opened it after reaching land...

Urashima Taro , a story that teaches about the importance of obedience over happiness. A turtle who gave a gift to a fisherman, 
but ended up sad because of his disobedience...

For those who are obedient and hold will be better off rewarded than those who are disobedient and sell for short term happiness.

*/

// SPDX-License-Identifier: MIT

pragma solidity 0.8.15;


library SafeMath {
    function add(uint256 a, uint256 b) internal pure returns (uint256) {return a + b;}
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {return a - b;}
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {return a * b;}
    function div(uint256 a, uint256 b) internal pure returns (uint256) {return a / b;}
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {return a % b;}
    
    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);}}

    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {if(b > a) return(false, 0); return(true, a - b);}}

    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {if (a == 0) return(true, 0); uint256 c = a * b;
        if(c / a != b) return(false, 0); return(true, c);}}

    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {if(b == 0) return(false, 0); return(true, a / b);}}

    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {if(b == 0) return(false, 0); return(true, a % b);}}

    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        unchecked{require(b <= a, errorMessage); return a - b;}}

    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        unchecked{require(b > 0, errorMessage); return a / b;}}

    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        unchecked{require(b > 0, errorMessage); return a % b;}}}

interface IERC20 {
    function totalSupply() external view returns (uint256);
    function decimals() external view returns (uint8);
    function symbol() external view returns (string memory);
    function name() external view returns (string memory);
    function getOwner() external view returns (address);
    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 Ownable {
    address internal owner;
    constructor(address _owner) {owner = _owner;}
    modifier onlyOwner() {require(isOwner(msg.sender), "!OWNER"); _;}
    function isOwner(address account) public view returns (bool) {return account == owner;}
    function transferOwnership(address payable adr) public onlyOwner {owner = adr; emit OwnershipTransferred(adr);}
    event OwnershipTransferred(address owner);
}

interface IFactory{
        function createPair(address tokenA, address tokenB) external returns (address pair);
        function getPair(address tokenA, address tokenB) external view returns (address pair);
}

interface IRouter {
    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);

    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 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 Urashima is IERC20, Ownable {
    using SafeMath for uint256;
    string private constant _name = 'Urashima';
    string private constant _symbol = '$Taro';
    uint8 private constant _decimals = 9;
    uint256 private _totalSupply = 100 * 10**9 * (10 ** _decimals);
    uint256 public _maxTxAmount = ( _totalSupply * 300 ) / 10000;
    uint256 public _maxWalletToken = ( _totalSupply * 300 ) / 10000;
    mapping (address => uint256) _balances;
    mapping (address => mapping (address => uint256)) private _allowances;
    mapping (address => bool) public isFeeExempt;
    IRouter router;
    address public pair;
    bool tradingAllowed = false;
    uint256 liquidityFee = 100;
    uint256 marketingFee = 400;
    uint256 totalFee = 500;
    uint256 sellFee = 500;
    uint256 transferFee = 0;
    uint256 feeDenominator = 10000;
    bool swapEnabled = true;
    uint256 swapTimes;
    bool swapping; 
    uint256 swapThreshold = ( _totalSupply * 600 ) / 100000;
    uint256 _minTokenAmount = ( _totalSupply * 15 ) / 100000;
    modifier lockTheSwap {swapping = true; _; swapping = false;}

    address public constant liquidity_receiver = 0xbDcFE94f6B2e9b5B5c5534143D408CDB6030C3A2; 
    address public constant DEAD = 0x000000000000000000000000000000000000dEaD;
    address public constant marketing_receiver = 0xbDcFE94f6B2e9b5B5c5534143D408CDB6030C3A2;

    constructor() Ownable(msg.sender) {
        IRouter _router = IRouter(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
        address _pair = IFactory(_router.factory()).createPair(address(this), _router.WETH());
        router = _router;
        pair = _pair;
        isFeeExempt[address(this)] = true;
        isFeeExempt[liquidity_receiver] = true;
        isFeeExempt[marketing_receiver] = true;
        isFeeExempt[msg.sender] = true;
        _balances[msg.sender] = _totalSupply;
        emit Transfer(address(0), msg.sender, _totalSupply);
    }

    receive() external payable {}

    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 view override returns (uint256) {return _totalSupply;}
    function getOwner() external view override returns (address) { return owner; }
    function balanceOf(address account) public view override returns (uint256) {return _balances[account];}
    function transfer(address recipient, uint256 amount) public override returns (bool) {_transfer(msg.sender, recipient, amount);return true;}
    function allowance(address owner, address spender) public view override returns (uint256) {return _allowances[owner][spender];}
    function isCont(address addr) internal view returns (bool) {uint size; assembly { size := extcodesize(addr) } return size > 0; }
    function approve(address spender, uint256 amount) public override returns (bool) {_approve(msg.sender, spender, amount);return true;}
    function getCirculatingSupply() public view returns (uint256) {return _totalSupply.sub(balanceOf(DEAD)).sub(balanceOf(address(0)));}

    function transferFrom(address sender, address recipient, uint256 amount) public override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, msg.sender, _allowances[sender][msg.sender].sub(amount, "ERC20: transfer amount exceeds allowance"));
        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 _transfer(address sender, address recipient, uint256 amount) private {
        preTxCheck(sender, recipient, amount);
        checktradingAllowed(sender, recipient);
        checkMaxWallet(sender, recipient, amount); 
        swapbackCounters(sender, recipient);
        checkTxLimit(sender, recipient, amount); 
        swapBack(sender, recipient, amount);
        _balances[sender] = _balances[sender].sub(amount);
        uint256 amountReceived = shouldTakeFee(sender, recipient) ? takeFee(sender, recipient, amount) : amount;
        _balances[recipient] = _balances[recipient].add(amountReceived);
        emit Transfer(sender, recipient, amountReceived);
    }

    function preTxCheck(address sender, address recipient, uint256 amount) internal view {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");
        require(amount > uint256(0), "Transfer amount must be greater than zero");
        require(amount <= balanceOf(sender),"You are trying to transfer more than your balance");
    }

    function checktradingAllowed(address sender, address recipient) internal view {
        if(!isFeeExempt[sender] && !isFeeExempt[recipient]){require(tradingAllowed, "tradingAllowed");}
    }
    
    function checkMaxWallet(address sender, address recipient, uint256 amount) internal view {
        if(isCont(recipient) && sender != pair && !isCont(sender)){require((_balances[recipient].add(amount)) <= _totalSupply);}
        if(!isFeeExempt[sender] && !isFeeExempt[recipient] && recipient != address(pair) && recipient != address(DEAD)){
            require((_balances[recipient].add(amount)) <= _maxWalletToken, "Exceeds maximum wallet amount.");}
    }

    function swapbackCounters(address sender, address recipient) internal {
        if(recipient == pair && !isFeeExempt[sender]){swapTimes += uint256(1);}
    }

    function startTrading() external onlyOwner {
        tradingAllowed = true; 
    }

    function shouldTakeFee(address sender, address recipient) internal view returns (bool) {
        return !isFeeExempt[sender] && !isFeeExempt[recipient];
    }

    function takeFee(address sender, address recipient, uint256 amount) internal returns (uint256) {
        uint256 feeAmount = amount.div(feeDenominator).mul(getTotalFee(sender, recipient));
        _balances[address(this)] = _balances[address(this)].add(feeAmount);
        emit Transfer(sender, address(this), feeAmount); 
        return amount.sub(feeAmount);
    }

    function getTotalFee(address sender, address recipient) internal view returns (uint256) {
        if(recipient == pair){return sellFee;}
        if(sender == pair){return totalFee;}
        return transferFee;
    }

    function checkTxLimit(address sender, address recipient, uint256 amount) internal view {
        require(amount <= _maxTxAmount || isFeeExempt[sender] || isFeeExempt[recipient], "TX Limit Exceeded");
    }

    function shouldSwapBack(address sender, address recipient, uint256 amount) internal view returns (bool) {
        bool aboveMin = amount >= _minTokenAmount;
        bool aboveThreshold = balanceOf(address(this)) >= swapThreshold;
        return !swapping && swapEnabled && aboveMin && !isFeeExempt[sender] && recipient == pair && swapTimes >= uint256(2) && aboveThreshold;
    }

    function swapBack(address sender, address recipient, uint256 amount) internal {
        if(shouldSwapBack(sender, recipient, amount)){swapAndLiquify(swapThreshold); swapTimes = 0;}
    }

    function swapAndLiquify(uint256 tokens) private lockTheSwap {
        uint256 denominator = (liquidityFee.add(marketingFee)) * 2;
        uint256 tokensToAddLiquidityWith = tokens.mul(liquidityFee).div(denominator);
        uint256 toSwap = tokens.sub(tokensToAddLiquidityWith);
        uint256 initialBalance = address(this).balance;
        swapTokensForETH(toSwap);
        uint256 deltaBalance = address(this).balance.sub(initialBalance);
        uint256 unitBalance= deltaBalance.div(denominator.sub(liquidityFee));
        uint256 ETHToAddLiquidityWith = unitBalance.mul(liquidityFee);
        if(ETHToAddLiquidityWith > uint256(0)){
            addLiquidity(tokensToAddLiquidityWith, ETHToAddLiquidityWith); }
        uint256 remainingBalance = address(this).balance;
        if(remainingBalance > uint256(0)){
          payable(marketing_receiver).transfer(remainingBalance); }
    }

    function addLiquidity(uint256 tokenAmount, uint256 ETHAmount) private {
        _approve(address(this), address(router), tokenAmount);
        router.addLiquidityETH{value: ETHAmount}(
            address(this),
            tokenAmount,
            0,
            0,
            liquidity_receiver,
            block.timestamp);
    }

    function swapTokensForETH(uint256 tokenAmount) private {
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = router.WETH();
        _approve(address(this), address(router), tokenAmount);
        router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0,
            path,
            address(this),
            block.timestamp);
    }

}