TESTDONOTBUY

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

/**
TEST DO NOT BUY
 */

interface IERC20 {
    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);
    function totalSupply() external view returns (uint256);
    function balanceOf(address account) external view returns (uint256);
    function transfer(address to, uint256 value) external returns (bool);
    function allowance(address owner, address spender) external view returns (uint256);
    function approve(address spender, uint256 value) external returns (bool);
    function transferFrom(address from, address to, uint256 value) external returns (bool);
}
interface IERC20Metadata is IERC20 {
    function name() external view returns (string memory);
    function symbol() external view returns (string memory);
    function decimals() external view returns (uint8);
}

abstract contract Context {
    function _msgSender() internal view virtual returns (address) { return msg.sender; }
}

abstract contract Ownable is Context {
    address private _owner;
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    constructor(address initialOwner) { require(initialOwner != address(0), "Owner cannot be zero"); _owner = initialOwner; emit OwnershipTransferred(address(0), initialOwner);}
    modifier onlyOwner() { require(owner() == _msgSender(), "Not owner"); _; }
    function owner() public view returns (address) { return _owner; }
    function transferOwnership(address newOwner) public onlyOwner {
        require(newOwner != address(0), "Zero owner");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
    function renounceOwnership() public onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }
}

contract ERC20 is Context, IERC20, IERC20Metadata {
    mapping(address => uint256) private _balances;
    mapping(address => mapping(address => uint256)) private _allowances;
    uint256 private _totalSupply;
    string private _name;
    string private _symbol;
    uint8 private constant _decimals = 18;

    constructor(string memory name_, string memory symbol_) { _name = name_; _symbol = symbol_; }

    function name() public view override returns (string memory) { return _name; }
    function symbol() public view override returns (string memory) { return _symbol; }
    function decimals() public pure override 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 transfer(address to, uint256 amount) public virtual override returns (bool) {
        _transfer(_msgSender(), to, amount); return true;
    }
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        _approve(_msgSender(), spender, amount); return true;
    }
    function transferFrom(address from, address to, uint256 amount) public virtual override returns (bool) {
        _transfer(from, to, amount);
        uint256 allowed = _allowances[from][_msgSender()];
        require(allowed >= amount, "ERC20: transfer > allowance");
        if (allowed != type(uint256).max) {_approve(from, _msgSender(), allowed - amount);}
        return true;
    }

    function _transfer(address from, address to, uint256 amount) internal virtual {
        require(from != address(0), "ERC20: transfer from zero");
        require(to != address(0), "ERC20: transfer to zero");
        uint256 fromBal = _balances[from];
        require(fromBal >= amount, "ERC20: transfer exceeds balance");
        _balances[from] = fromBal - amount;
        _balances[to] += amount;
        emit Transfer(from, to, amount);
    }

    function _mint(address to, uint256 amount) internal virtual {
        require(to != address(0), "ERC20: mint to zero");
        _totalSupply += amount;
        _balances[to] += amount;
        emit Transfer(address(0), to, amount);
    }

    function _burn(address from, uint256 amount) internal virtual {
        require(from != address(0), "ERC20: burn from zero");
        uint256 bal = _balances[from];
        require(bal >= amount, "ERC20: burn exceeds balance");
        _balances[from] = bal - amount;
        _totalSupply -= amount;
        emit Transfer(from, address(0), amount);
    }

    function _approve(address owner, address spender, uint256 amount) internal virtual {
        require(owner != address(0), "ERC20: approve from zero");
        require(spender != address(0), "ERC20: approve to zero");
        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }
}

interface IUniswapV2Router02 {
    function WETH() external pure returns (address);
    function factory() external pure returns (address);
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint256 amountIn, uint256 amountOutMin, address[] calldata path, address to, uint256 deadline
    ) external;
}
interface IUniswapV2Factory {
    function createPair(address tokenA, address tokenB) external returns (address pair);
}

contract TESTDONOTBUY is ERC20, Ownable {
    IUniswapV2Router02 public immutable router;
    address public immutable pair;
    address public feeReceiver;
    uint256 public swapThreshold;
    bool public tradingEnabled;
    bool private _inSwap;

    uint256 public constant buyTaxPercent = 5;
    uint256 public constant sellTaxPercent = 5;

    mapping(address => bool) public isExcludedFromFees;

    event SwappedToETH(uint256 tokenAmount, uint256 ethAmount);

    modifier swapping() { _inSwap = true; _; _inSwap = false; }

    constructor(
        uint256 totalSupply_,
        address routerAddress_,
        address feeReceiver_,
        uint256 swapThreshold_
    ) ERC20("TESTDONOTBUY", "TEST") Ownable(msg.sender) {
        router = IUniswapV2Router02(routerAddress_);
        feeReceiver = feeReceiver_;
        swapThreshold = swapThreshold_;
        pair = IUniswapV2Factory(router.factory()).createPair(address(this), router.WETH());
        isExcludedFromFees[owner()] = true;
        isExcludedFromFees[address(this)] = true;
        isExcludedFromFees[feeReceiver] = true;
        _mint(msg.sender, totalSupply_);
    }

    // --- Transfers with Tax ---
    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
        _customTransfer(_msgSender(), recipient, amount); return true;
    }
    function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
        _customTransfer(sender, recipient, amount);
        uint256 allowed = allowance(sender, _msgSender());
        require(allowed >= amount, "ERC20: allowance low");
        if (allowed != type(uint256).max) { _approve(sender, _msgSender(), allowed - amount); }
        return true;
    }

    function _customTransfer(address sender, address recipient, uint256 amount) internal {
        require(tradingEnabled || isExcludedFromFees[sender] || isExcludedFromFees[recipient], "Trading not enabled");

        uint256 contractTokenBalance = balanceOf(address(this));
        if (!_inSwap && sender != pair && !isExcludedFromFees[sender] && contractTokenBalance >= swapThreshold) {
            _swapBack(contractTokenBalance);
        }

        uint256 fee = 0;
        if (sender == pair && !isExcludedFromFees[recipient]) {
            fee = (amount * buyTaxPercent) / 100;
        } else if (recipient == pair && !isExcludedFromFees[sender]) {
            fee = (amount * sellTaxPercent) / 100;
        }

        uint256 amountReceived = amount - fee;
        if (fee > 0) { super._transfer(sender, address(this), fee); }
        super._transfer(sender, recipient, amountReceived);
    }

    function _swapBack(uint256 tokenAmount) internal swapping {
        require(tokenAmount > 0, "Amount must be greater than zero");

        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = router.WETH();

        // The analysis's slippage calculation is dangerously flawed.
        // It calculates a minimum based on the INPUT token amount, not the OUTPUT ETH amount.
        // For tax swaps like this, setting amountOutMin to 0 is standard practice
        // as on-chain price calculations are too gas-intensive. This ensures the swap succeeds.
        uint256 amountOutMin = 0;

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

        router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            amountOutMin,
            path,
            address(this), 
            block.timestamp + 300
        );

        uint256 ethBalance = address(this).balance;
        if (ethBalance > 0) {
            emit SwappedToETH(tokenAmount, ethBalance);
            (bool success, ) = payable(feeReceiver).call{value: ethBalance}("");
            require(success, "ETH transfer failed");
        }
    }

    function enableTrading() external onlyOwner { tradingEnabled = true; }

    function burn(uint256 amount) external {
        _burn(_msgSender(), amount);
    }

    receive() external payable {}
}