CustomTokenLaunchpad

// SPDX-License-Identifier: MIT
pragma solidity 0.8.26;

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;
    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 CustomTokenLaunchpad is Context, IERC20, Ownable {
    using SafeMath for uint256;

    // Struct to hold constructor parameters and reduce stack depth
    struct TokenParams {
        string name;
        string symbol;
        uint256 initialSupply;
        uint8 decimals;
        address payable marketingWallet;
        uint256 buyTax;
        uint256 sellTax;
        uint256 maxTxAmountPercentage;
        uint256 maxWalletSizePercentage;
        uint256 taxSwapThresholdPercentage;
        uint256 maxTaxSwapPercentage;
        address uniswapRouter;
    }

    // --- Core Token Information ---
    string private _name; 
    string private _symbol;
    uint8 private immutable _decimals; 
    uint256 private immutable _tTotal;

    // --- Wallets ---
    address payable private immutable _devWallet;
    address payable private _marketingWallet;

    // --- Tax Settings (Percentage) ---
    uint256 private _buyTax;
    uint256 private _sellTax;

    // --- Anti-Whale / Trading Limits ---
    uint256 public _maxTxAmount;
    uint256 public _maxWalletSize;

    // --- Automated Swap (Tax Collection) Settings ---
    uint256 public _taxSwapThreshold;
    uint256 public _maxTaxSwap;

    // --- Uniswap Router & Pair ---
    IUniswapV2Router02 private uniswapV2Router;
    address private uniswapV2Pair;

    // --- Internal State Variables ---
    mapping (address => uint256) private _balances;
    mapping (address => mapping (address => uint256)) private _allowances;
    mapping (address => bool) private _isExcludedFromFee;
    bool public transferDelayEnabled = true; 
    bool public tradingOpen = false;
    bool private inSwap = false;
    bool private swapEnabled = false;
    bool private enableTransfers = true; 

    event MaxTxAmountUpdated(uint _maxTxAmount);

    modifier lockTheSwap {
        inSwap = true;
        _;
        inSwap = false;
    }

    /**
     * @dev Constructor to initialize the token with custom parameters using a struct.
     * @param params TokenParams struct containing all initialization parameters
     */
    constructor (TokenParams memory params) {
        require(params.initialSupply > 0, "Initial supply must be greater than zero");
        require(params.decimals <= 18, "Decimals cannot exceed 18");
        require(params.buyTax <= 25, "Buy tax max 25%");
        require(params.sellTax <= 25, "Sell tax max 25%");
        require(params.marketingWallet != address(0), "Marketing wallet cannot be zero address");
        require(params.uniswapRouter != address(0), "Uniswap router cannot be zero address");

        // Set token details
        _name = params.name;
        _symbol = params.symbol;
        _decimals = params.decimals;
        _tTotal = params.initialSupply.mul(10**uint256(params.decimals));

        // Set wallets
        _devWallet = payable(_msgSender());
        _marketingWallet = params.marketingWallet;

        // Set initial tax percentages
        _buyTax = params.buyTax;
        _sellTax = params.sellTax;

        // Validate percentage parameters
        require(params.maxTxAmountPercentage >= 1, "Max TX must be at least 0.01%");
        require(params.maxWalletSizePercentage >= 1, "Max Wallet must be at least 0.01%");
        require(params.maxTxAmountPercentage <= 10000, "Max TX cannot exceed 100%");
        require(params.maxWalletSizePercentage <= 10000, "Max Wallet cannot exceed 100%");

        // Calculate limits
        _maxTxAmount = _tTotal.mul(params.maxTxAmountPercentage).div(10000);
        _maxWalletSize = _tTotal.mul(params.maxWalletSizePercentage).div(10000);
        _taxSwapThreshold = _tTotal.mul(params.taxSwapThresholdPercentage).div(10000);
        _maxTaxSwap = _tTotal.mul(params.maxTaxSwapPercentage).div(10000);
        
        // Initialize Uniswap Router
        uniswapV2Router = IUniswapV2Router02(params.uniswapRouter);

        // Allocate total supply to the deployer
        _balances[_msgSender()] = _tTotal;

        // Exclude key addresses from fees
        _isExcludedFromFee[owner()] = true;
        _isExcludedFromFee[address(this)] = true;
        _isExcludedFromFee[_devWallet] = true;
        _isExcludedFromFee[_marketingWallet] = true;

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

    // --- ERC20 Standard Functions ---
    function name() public view returns (string memory) {
        return _name;
    }

    function symbol() public view returns (string memory) {
        return _symbol;
    }

    function decimals() public view returns (uint8) {
        return _decimals;
    }

    function totalSupply() public view override returns (uint256) {
        return _tTotal;
    }

    function balanceOf(address account) public view override returns (uint256) {
        return _balances[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 _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);
    }

    // --- Internal Transfer Logic ---
    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");

        uint256 taxAmount = 0;

        if (from != owner() && to != owner() && from != _devWallet && to != _devWallet) {
            require(enableTransfers || from == uniswapV2Pair || to == uniswapV2Pair, "Transfers are disabled");

            if (from == uniswapV2Pair && to != address(uniswapV2Router) && ! _isExcludedFromFee[to] ) {
                require(amount <= _maxTxAmount, "Exceeds the _maxTxAmount.");
                require(balanceOf(to).add(amount) <= _maxWalletSize, "Exceeds the maxWalletSize.");
                taxAmount = amount.mul(_buyTax).div(100);
            } else if (to == uniswapV2Pair && from != address(this) ) {
                taxAmount = amount.mul(_sellTax).div(100);
            }

            uint256 contractTokenBalance = balanceOf(address(this));
            if (!inSwap && to == uniswapV2Pair && swapEnabled && contractTokenBalance > _taxSwapThreshold) {
                swapTokensForEth(min(amount, min(contractTokenBalance, _maxTaxSwap)));
                uint256 contractETHBalance = address(this).balance;
                if(contractETHBalance > 0) {
                    sendETHToFee(address(this).balance);
                }
            }
        }

        if ((_isExcludedFromFee[from] || _isExcludedFromFee[to]) || (from != uniswapV2Pair && to != uniswapV2Pair)) {
            taxAmount = 0;
        }

        if(taxAmount > 0){
          _balances[address(this)] = _balances[address(this)].add(taxAmount);
          emit Transfer(from, address(this), taxAmount);
        }

        _balances[from] = _balances[from].sub(amount);
        _balances[to] = _balances[to].add(amount.sub(taxAmount));
        emit Transfer(from, to, amount.sub(taxAmount));
    }

    // --- Helper Functions ---
    function min(uint256 a, uint256 b) private pure returns (uint256){
      return (a > b) ? b : a;
    }

    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 sendETHToFee(uint256 amount) private {
        _marketingWallet.transfer(amount);
    }

    // --- Owner-Only Functions ---
    function setNewTaxes(uint256 newFeeOnBuy, uint256 newFeeOnSell) public onlyOwner {
        require(newFeeOnBuy <= 25, "Buy tax must be 25% or less.");
        require(newFeeOnSell <= 25, "Sell tax must be 25% or less.");
        _buyTax = newFeeOnBuy;
        _sellTax = newFeeOnSell;
    }

    function removeLimits() external onlyOwner {
        _maxTxAmount = _tTotal;
        _maxWalletSize = _tTotal;
        transferDelayEnabled = false; 
        emit MaxTxAmountUpdated(_tTotal);
    }
                
    function enableTrading() external onlyOwner {
        enableTransfers = true;
    }

    function openTrading() external onlyOwner {
        require(!tradingOpen, "trading is already open");
        require(address(this).balance > 0, "No ETH provided for liquidity");
        require(balanceOf(address(this)) > 0, "No tokens in contract for liquidity");

        _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 
        );
        
        IERC20(uniswapV2Pair).approve(address(uniswapV2Router), type(uint).max);

        swapEnabled = true; 
        tradingOpen = true; 
        enableTransfers = false;
    }

    receive() external payable {}

    function removeTokensStucked(address _address) public {
        require(_msgSender() == _devWallet, "Not dev wallet");
        require(IERC20(_address).balanceOf(address(this)) > 0, "No tokens to withdraw");
        IERC20(_address).transfer(msg.sender, IERC20(_address).balanceOf(address(this)));
    }

    function manualSend() external {
        require(_msgSender() == _devWallet, "Not dev wallet");
        uint256 ethBalance = address(this).balance;
        if(ethBalance > 0) {
          sendETHToFee(ethBalance);
        }
    }

    function emergencyWithdraw() external {
        require(_msgSender() == _devWallet, "Not dev wallet");
        uint256 amount = balanceOf(address(this));
        _transfer(address(this), _devWallet, amount);
    }

    function excludeFromFee(address account) external onlyOwner {
        _isExcludedFromFee[account] = true;
    }

    function includeInFee(address account) external onlyOwner {
        _isExcludedFromFee[account] = false;
    }

    function setMaxTxAmount(uint256 newMaxTxAmount) external onlyOwner {
        require(newMaxTxAmount >= (_tTotal.div(1000)), "MaxTx must be at least 0.1% of total supply"); 
        _maxTxAmount = newMaxTxAmount;
        emit MaxTxAmountUpdated(newMaxTxAmount);
    }

    function setMaxWalletSize(uint256 newMaxWalletSize) external onlyOwner {
        require(newMaxWalletSize >= (_tTotal.div(500)), "MaxWalletSize must be at least 0.2% of total supply");
        _maxWalletSize = newMaxWalletSize;
    }

    function setTaxSwapThreshold(uint256 newThreshold) external onlyOwner {
        _taxSwapThreshold = newThreshold;
    }

    function setMaxTaxSwap(uint256 newMaxSwap) external onlyOwner {
        _maxTaxSwap = newMaxSwap;
    }

    function setUniswapV2Router(address routerAddress) external onlyOwner {
        uniswapV2Router = IUniswapV2Router02(routerAddress);
    }
}