// SPDX-License-Identifier: Unlicensed

pragma solidity 0.8.18;

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);
}

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 transferOwnership(address newOwner) public onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }

    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 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);
}

contract QUDEFI is Context, IERC20, Ownable {
    uint256 private constant _totalSupply = 100_000_000e18;
    uint256 private constant minSwap = 25_000e18;
    uint8 private constant _decimals = 18;

    IUniswapV2Router02 immutable uniswapV2Router;
    address immutable uniswapV2Pair;
    address immutable USDT;
    address payable immutable taxWallet;

    uint256 public buyTax;
    uint256 public sellTax;

    uint8 private inSwapAndLiquify;

    string private constant _name = "QUDEFI";
    string private constant _symbol = "QDFI";

    mapping(address => uint256) private _balance;
    mapping(address => mapping(address => uint256)) private _allowances;
    mapping(address => bool) private _isExcludedFromFeeWallet;

    constructor() {
        uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
        USDT = 0xdAC17F958D2ee523a2206206994597C13D831ec7;
        buyTax = 1;
        sellTax = 2;

        uniswapV2Pair = IUniswapV2Factory(uniswapV2Router.factory()).createPair(address(this), USDT);

        taxWallet = payable(0x72A1519Cf49da4f2b0F6490C3C96F46caab19e74);
        _balance[msg.sender] = _totalSupply;
        _isExcludedFromFeeWallet[taxWallet] = true;
        _isExcludedFromFeeWallet[msg.sender] = true;
        _isExcludedFromFeeWallet[address(this)] = true;
        _allowances[address(this)][address(uniswapV2Router)] = type(uint256)
            .max;
        _allowances[msg.sender][address(uniswapV2Router)] = type(uint256).max;
        _allowances[taxWallet][address(uniswapV2Router)] = type(uint256)
            .max;


        emit Transfer(address(0), _msgSender(), _totalSupply);
    }

    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 _totalSupply;
    }

    function balanceOf(address account) public view override returns (uint256) {
        return _balance[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()] - 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 addExcludedWallet(address wallet) external onlyOwner {
        _isExcludedFromFeeWallet[wallet] = true;
    }

    function removeExcludedWallet(address wallet) external onlyOwner {
        _isExcludedFromFeeWallet[wallet] = false;
    }

    function changeTax(uint256 newBuyTax, uint256 newSellTax) external onlyOwner {
        buyTax = newBuyTax;
        sellTax = newSellTax;
    }

    function _transfer(
    address from,
    address to,
    uint256 amount
    ) private {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(amount > 1e9, "Min transfer amt");

        uint256 _tax;
        if (_isExcludedFromFeeWallet[from] || _isExcludedFromFeeWallet[to]) {
            _tax = 0;
        } else {
            if (inSwapAndLiquify == 1) {
                //No tax transfer
                _balance[from] -= amount;
                _balance[to] += amount;
                emit Transfer(from, to, amount);
                return;
            }

            if (from == uniswapV2Pair) {
                _tax = buyTax;
            } else if (to == uniswapV2Pair) {
                uint256 tokensToSwap = _balance[address(this)];
                if (tokensToSwap > minSwap && inSwapAndLiquify == 0) {
                    inSwapAndLiquify = 1;
                    _swapTokensForUSDT(tokensToSwap);
                    inSwapAndLiquify = 0;
                }
                _tax = sellTax;
            } else {
                _tax = 0;
            }
        }

        if (_tax != 0) {
            //Tax transfer
            uint256 taxTokens = (amount * _tax) / 100;
            uint256 transferAmount = amount - taxTokens;

            _balance[from] -= amount;
            _balance[to] += transferAmount;
            _balance[address(this)] += taxTokens;

            emit Transfer(from, address(this), taxTokens);
            emit Transfer(from, to, transferAmount);

        } else {
            //No tax transfer
            _balance[from] -= amount;
            _balance[to] += amount;

            emit Transfer(from, to, amount);
        }
    }

    function _swapTokensForUSDT(uint256 tokenAmount) private {
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = USDT;

        _approve(address(this), address(uniswapV2Router), tokenAmount);

        // make the swap
        uniswapV2Router.swapExactTokensForTokensSupportingFeeOnTransferTokens(
            tokenAmount,
            0, // accept any amount of USDT
            path,
            taxWallet,
            block.timestamp
        );
    }


    receive() external payable {}
}

{
  "compilationTarget": {
    "contracts/QUDEFI.sol": "QUDEFI"
  },
  "evmVersion": "paris",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": false,
    "runs": 200
  },
  "remappings": []
}