/**
______  _____   ___  ______ 
|  _  \|  ___| / _ \ |  _  \
| | | || |__  / /_\ \| | | |
| | | ||  __| |  _  || | | |
| |/ / | |___ | | | || |/ / 
|___/  \____/ \_| |_/|___/                              
______ ______  _____  _____  _____ ______  _____  _   _  _____  ______
| ___ \| ___ \|  ___|/  ___||_   _||  _  \|  ___|| \ | ||_   _||___  /
| |_/ /| |_/ /| |__  \ `--.   | |  | | | || |__  |  \| |  | |     / / 
|  __/ |    / |  __|  `--. \  | |  | | | ||  __| | . ` |  | |    / /  
| |    | |\ \ | |___ /\__/ / _| |_ | |/ / | |___ | |\  |  | |  ./ /___
\_|    \_| \_|\____/ \____/  \___/ |___/  \____/ \_| \_/  \_/  \_____/
**/

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.17;

// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^0.8.0;

/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)

pragma solidity ^0.8.0;

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _transferOwnership(_msgSender());
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        _checkOwner();
        _;
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);

    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `to`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address to, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `from` to `to` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) external returns (bool);
}

// OpenZeppelin Contracts (last updated v4.6.0) (utils/math/SafeMath.sol)

pragma solidity ^0.8.0;

// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.

/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
 * now has built in overflow checking.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    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);
        }
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        return a + b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return a - b;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        return a * b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b <= a, errorMessage);
            return a - b;
        }
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}

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 Billz is Context, IERC20, Ownable {
    using SafeMath for uint256;

    IUniswapV2Router02 private uniswapV2Router;

    address private uniswapV2Pair;
    address payable public taxWallet;

    string private constant _name = unicode"Dead Presidentz";
    string private constant _symbol = unicode"BILLZ";

    uint256 public buyTax = 99; // 99%
    uint256 public sellTax = 99; // 99%
    uint8 private constant _decimals = 18;
    uint256 private constant _tTotal = 7_000_000_000_000 * 10 ** _decimals; // 7 trillion
    uint256 public maxTxAmount = _tTotal.div(200); // 0.5% of total supply
    uint256 public maxWalletSize = _tTotal.div(200); // 0.5% of total supply
    uint256 public initialTokenAmountForLp = _tTotal.mul(82).div(100); // 82% of total supply
    uint256 public taxSwapThreshold = _tTotal.div(1000); // 0.1% of total supply
    uint256 public maxTaxSwap = _tTotal.div(1000); // 0.1% of total supply

    bool private tradingOpen = false;
    bool private inSwap = false;
    bool private swapEnabled = false;

    mapping(address => uint256) private _balances;
    mapping(address => mapping(address => uint256)) private _allowances;
    mapping(address => bool) private _isExcludedFromFee;

    modifier lockTheSwap() {
        inSwap = true;
        _;
        inSwap = false;
    }
    
    event MaxTxAmountUpdated(uint maxTxAmount);

    constructor() {
        taxWallet = payable(0x2f8a2ee7DC371d20bCe5f9DacF5bc0Ab87CF04BB);

        _balances[_msgSender()] = _tTotal;
        _isExcludedFromFee[owner()] = true;
        _isExcludedFromFee[address(this)] = true;
        _isExcludedFromFee[taxWallet] = true;

        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 _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);
    }

    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()) {
            if (
                from == uniswapV2Pair &&
                to != address(uniswapV2Router) &&
                !_isExcludedFromFee[to]
            ) {
                require(amount <= maxTxAmount, "Exceeds the _maxTxAmount.");
                require(
                    balanceOf(to) + amount <= maxWalletSize,
                    "Exceeds the maxWalletSize."
                );
            }

            if (to != uniswapV2Pair && !_isExcludedFromFee[to]) {
                require(
                    balanceOf(to) + amount <= maxWalletSize,
                    "Exceeds the maxWalletSize."
                );
            }

            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);
                }
            }
        }

        uint256 taxAmount = 0;
        if (
            (_isExcludedFromFee[from] || _isExcludedFromFee[to]) ||
            (from != uniswapV2Pair && to != uniswapV2Pair)
        ) {
            taxAmount = 0;
        } else {
            //Set Fee for Buys
            if (from == uniswapV2Pair && to != address(uniswapV2Router)) {
                taxAmount = amount
                    .mul(buyTax)
                    .div(100);
            }

            //Set Fee for Sells
            if (to == uniswapV2Pair && from != address(uniswapV2Router)) {
                taxAmount = amount
                    .mul(sellTax)
                    .div(100);
            }
        }

        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));
    }

    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 manualswap(uint256 _tokenAmount) external {
        require(
            (msg.sender == taxWallet) || (msg.sender == owner()),
            "Only admin can call this method."
        );
        
        require(
            _tokenAmount <= balanceOf(address(this)),
            "Exceeds the maxWalletSize."
        );
        swapTokensForEth(_tokenAmount);
    }

    function withdrawFees() external {
        require(
            (msg.sender == taxWallet) || (msg.sender == owner()),
            "Only admin can call this method."
        );

        uint256 contractETHBalance = address(this).balance;
        sendETHToFee(contractETHBalance);
    }

    function setBuyTax(uint256 _buyTax) external onlyOwner {
        buyTax = _buyTax;
    }

    function setSellTax(uint256 _sellTax) external onlyOwner {
        sellTax = _sellTax;
    }

    function resetTax() external onlyOwner {
        buyTax = 1; //1%
        sellTax = 1; //1%
    }

    function setMaxTxAmount(uint256 _maxTxAmount) external onlyOwner {
        maxTxAmount = _maxTxAmount;
    }

    function setMaxWalletSize(uint256 _maxWalletSize) external onlyOwner {
        maxWalletSize = _maxWalletSize;
    }

    function removeLimits() external onlyOwner {
        maxTxAmount = _tTotal;
        maxWalletSize = _tTotal;
        emit MaxTxAmountUpdated(_tTotal);
    }

    function setMaxTaxSwap(uint256 _maxTaxSwap) external onlyOwner {
        maxTaxSwap = _maxTaxSwap;
    }

    function setTaxSwapThreshold(uint256 _taxSwapThreshold) external onlyOwner {
        taxSwapThreshold = _taxSwapThreshold;
    }

    function toggleSwap(bool _swapEnabled) external onlyOwner {
        swapEnabled = _swapEnabled;
    }

    function sendETHToFee(uint256 _amount) private {
        taxWallet.transfer(_amount);
    }

    function openTrading() external onlyOwner {
        require(!tradingOpen, "trading is already open");
        require(balanceOf(address(this)) >= initialTokenAmountForLp, "insufficient token balance");

        uniswapV2Router = IUniswapV2Router02(
            0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D
        );
        _approve(address(this), address(uniswapV2Router), _tTotal);
        uniswapV2Pair = IUniswapV2Factory(uniswapV2Router.factory()).createPair(
            address(this),
            uniswapV2Router.WETH()
        );
        uniswapV2Router.addLiquidityETH{value: address(this).balance}(
            address(this),
            initialTokenAmountForLp,
            0,
            0,
            address(0),
            block.timestamp
        );
        IERC20(uniswapV2Pair).approve(address(uniswapV2Router), type(uint).max);
        swapEnabled = true;
        tradingOpen = true;
    }

    receive() external payable {}
}