/*
                  (((((((((((((((*                               (((((((((((((((                                        
                  (((((((((((((((                                 ((((((((((((((                                        
                  ((((((########                                   (((((((((((((                                        
                  ((((((((((((#                                    ,((((((((((((                                        
                  ((((((((((((#                                    ,((((((((((((                                        
                  ((((((((((((                                      /(((((((((((                                        
                  (((((((((((.                                       (((((((((((                                        
                  ,                                                            ,                                        
                  ,                                                            ,                                         
                  #,,,,,,,,,,,,,,,.................................,,,,,,,,,,,,,                                        
                  #,,,,,,,,,,,,,,,.................................,,,,,,,,,,,,,                                        
                  #,,/////,/,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,......... %%%%/,,                                        
                  (((((((                                                %######                                        
                  ,,,,,,,         .(,                         @@,         ((((((                                        
                  #######         ..((((#@               ////@.,,         %%%%%%                                        
                  ///////         ...###/#####      (((///,..,,,,         &&&&&&                                        
                  ///////         ############.     (...........,         ######                                        
                  #######,                                               (((((((                                        
                  ########                                              (#######                                        
                  %%%%%%%%%                                            #%%%%%%%%                                        
                  &&&&&&&&&&(                 **@,#,,                 &&&&&&&&&&                                        
                  &&&&&&&&&&&&.            //(//&#(#/##,            ############                                        
                  %%%%%%%%%%%%%/,            #/(#(.,#,            ,#############                                        
                  %%%%%%%%%%%%%/,&(/                           (#/,#############                                        
                  %%%%%%%%%%%%%/,&((///(#                 #(/(/(#/,#############    

https://shadowswap.io

Shrouded in secrecy, powered by blockchain security.

Shadow Swap provides fully anonymous crypto transactions, ensuring your privacy and secury.
Trade with confidence, knowing your transactions are untraceable and your identity remains anonymous.

*/

// SPDX-License-Identifier: MIT

pragma solidity =0.8.17;

// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

/**
 * @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)

/**
 * @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) (utils/math/SafeMath.sol)

// 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;
        }
    }
}

// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)

/**
 * @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 v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)

/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 *
 * _Available since v4.1._
 */
interface IERC20Metadata is IERC20 {
    /**
     * @dev Returns the name of the token.
     */
    function name() external view returns (string memory);

    /**
     * @dev Returns the symbol of the token.
     */
    function symbol() external view returns (string memory);

    /**
     * @dev Returns the decimals places of the token.
     */
    function decimals() external view returns (uint8);
}

// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/ERC20.sol)

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin Contracts guidelines: functions revert
 * instead returning `false` on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC20
 * applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
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;

    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * The default value of {decimals} is 18. To select a different value for
     * {decimals} you should overload it.
     *
     * All two of these values are immutable: they can only be set once during
     * construction.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5.05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless this function is
     * overridden;
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual override returns (uint8) {
        return 18;
    }

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual override returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address to, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _transfer(owner, to, amount);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
     * `transferFrom`. This is semantically equivalent to an infinite approval.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, amount);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * NOTE: Does not update the allowance if the current allowance
     * is the maximum `uint256`.
     *
     * Requirements:
     *
     * - `from` and `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     * - the caller must have allowance for ``from``'s tokens of at least
     * `amount`.
     */
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) public virtual override returns (bool) {
        address spender = _msgSender();
        _spendAllowance(from, spender, amount);
        _transfer(from, to, amount);
        return true;
    }

    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, allowance(owner, spender) + addedValue);
        return true;
    }

    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        address owner = _msgSender();
        uint256 currentAllowance = allowance(owner, spender);
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked {
            _approve(owner, spender, currentAllowance - subtractedValue);
        }

        return true;
    }

    /**
     * @dev Moves `amount` of tokens from `from` to `to`.
     *
     * This internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     */
    function _transfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(from, to, amount);

        uint256 fromBalance = _balances[from];
        require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[from] = fromBalance - amount;
            // Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
            // decrementing then incrementing.
            _balances[to] += amount;
        }

        emit Transfer(from, to, amount);

        _afterTokenTransfer(from, to, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _totalSupply += amount;
        unchecked {
            // Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
            _balances[account] += amount;
        }
        emit Transfer(address(0), account, amount);

        _afterTokenTransfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");

        _beforeTokenTransfer(account, address(0), amount);

        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
            // Overflow not possible: amount <= accountBalance <= totalSupply.
            _totalSupply -= amount;
        }

        emit Transfer(account, address(0), amount);

        _afterTokenTransfer(account, address(0), amount);
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        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);
    }

    /**
     * @dev Updates `owner` s allowance for `spender` based on spent `amount`.
     *
     * Does not update the allowance amount in case of infinite allowance.
     * Revert if not enough allowance is available.
     *
     * Might emit an {Approval} event.
     */
    function _spendAllowance(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        uint256 currentAllowance = allowance(owner, spender);
        if (currentAllowance != type(uint256).max) {
            require(currentAllowance >= amount, "ERC20: insufficient allowance");
            unchecked {
                _approve(owner, spender, currentAllowance - amount);
            }
        }
    }

    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}

    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * has been transferred to `to`.
     * - when `from` is zero, `amount` tokens have been minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _afterTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}
}

interface IDEXFactory {
    function createPair(address tokenA, address tokenB) external returns (address pair);
}

interface IDEXRouter {
    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 swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}

contract ShadowToken is Context, ERC20, Ownable {
    using SafeMath for uint256;

    IDEXRouter private _dexRouter;

    mapping (address => uint) private _cooldown;

    mapping (address => bool) private _isExcludedFromFees;
    mapping (address => bool) private _isExcludedMaxTransactionAmount;
    mapping (address => bool) private _isBlacklisted;

    bool public tradingOpen;
    bool private _swapping;
    bool public swapEnabled = false;
    bool public cooldownEnabled = false;
    bool public feesEnabled = true;
    bool public transferFeesEnabled = true;

    uint256 private constant _tSupply = 100_000_000 ether;

    uint256 public maxBuyAmount = _tSupply;
    uint256 public maxSellAmount = _tSupply;
    uint256 public maxWalletAmount = _tSupply;

    uint256 public tradingOpenBlock = 0;
    uint256 private _blocksToBlacklist = 0;
    uint256 private _cooldownBlocks = 1;

    uint256 public constant FEE_DIVISOR = 1000;

    uint256 private _totalFees;
    uint256 private _marketingFee;
    uint256 private _nonkycCEXFee;
    uint256 private _liquidityFee;

    uint256 public buyMarketingFee = 20;
    uint256 private _previousBuyMarketingFee = buyMarketingFee;
    uint256 public buynonkycCEXFee = 10;
    uint256 private _previousBuynonKycCEXFee = buynonkycCEXFee;
    uint256 public buyLiquidityFee = 30;
    uint256 private _previousBuyLiquidityFee = buyLiquidityFee;

    uint256 public sellMarketingFee = 20;
    uint256 private _previousSellMktgFee = sellMarketingFee;
    uint256 public sellnonKycCEXFee = 10;
    uint256 private _previousSellDevFee = sellnonKycCEXFee;
    uint256 public sellLiquidityFee = 30;
    uint256 private _previousSellLiqFee = sellLiquidityFee;

    uint256 public transferMarketingFee = 20;
    uint256 private _previousTransferMarketingFee = transferMarketingFee;
    uint256 public transfernonKycCEXFee = 10;
    uint256 private _previousTransfernonKycCEXFee = transfernonKycCEXFee;
    uint256 public transferLiquidityFee = 30;
    uint256 private _previousTransferLiquidityFee = transferLiquidityFee;

    uint256 private _tokensForMarketing;
    uint256 private _tokensFornonKycCEX;
    uint256 private _tokensForLiquidity;
    uint256 private _swapTokensAtAmount = 0;

    address payable public marketingWalletAddress;
    address payable public nonkycCEXWalletAddress;
    address payable public liquidityWalletAddress;

    address private _dexPair;
    address constant private DEAD = 0x000000000000000000000000000000000000dEaD;
    address constant private ZERO = 0x0000000000000000000000000000000000000000;

    enum TransactionType {
        BUY,
        SELL,
        TRANSFER
    }

    event OpenTrading(uint256 tradingOpenBlock, uint256 _blocksToBlacklist);
    event SetMaxBuyAmount(uint256 newMaxBuyAmount);
    event SetMaxSellAmount(uint256 newMaxSellAmount);
    event SetMaxWalletAmount(uint256 newMaxWalletAmount);
    event SetSwapTokensAtAmount(uint256 newSwapTokensAtAmount);
    event SetBuyFee(uint256 buyMarketingFee, uint256 buynonkycCEXFee, uint256 buyLiquidityFee);
	event SetSellFee(uint256 sellMarketingFee, uint256 sellnonKycCEXFee, uint256 sellLiquidityFee);
    event SetTransferFee(uint256 transferMarketingFee, uint256 transfernonKycCEXFee, uint256 transferLiquidityFee);
    
    constructor (address payable _marketingWalletAddress, address payable _nonkycCEXWalletAddress, address payable _liquidityWalletAddress) ERC20("Shadow Token", "SHADOW") payable {
        require(_marketingWalletAddress != ZERO, "_marketingWalletAddress cannot be 0");
        require(_nonkycCEXWalletAddress != ZERO, "_nonkycCEXWalletAddress cannot be 0");
        require(_liquidityWalletAddress != ZERO, "_liquidityWalletAddress cannot be 0");

        marketingWalletAddress = _marketingWalletAddress;
        nonkycCEXWalletAddress = _nonkycCEXWalletAddress;
        liquidityWalletAddress = _liquidityWalletAddress;

        _isExcludedFromFees[owner()] = true;
        _isExcludedFromFees[address(this)] = true;
        _isExcludedFromFees[DEAD] = true;
        _isExcludedFromFees[marketingWalletAddress] = true;
        _isExcludedFromFees[nonkycCEXWalletAddress] = true;
        _isExcludedFromFees[liquidityWalletAddress] = true;

        _isExcludedMaxTransactionAmount[owner()] = true;
        _isExcludedMaxTransactionAmount[address(this)] = true;
        _isExcludedMaxTransactionAmount[DEAD] = true;
        _isExcludedMaxTransactionAmount[marketingWalletAddress] = true;
        _isExcludedMaxTransactionAmount[nonkycCEXWalletAddress] = true;
        _isExcludedMaxTransactionAmount[liquidityWalletAddress] = true;

        _mint(address(this), _tSupply.mul(60).div(100));
        _mint(owner(), _tSupply.mul(40).div(100));
    }

    function _transfer(address from, address to, uint256 amount) internal override {
        require(from != ZERO, "ERC20: transfer from the zero address");
        require(to != ZERO, "ERC20: transfer to the zero address");
        require(amount > 0, "Transfer amount must be greater than zero");

        bool takeFee = true;
        TransactionType txType = (from == _dexPair) ? TransactionType.BUY : (to == _dexPair) ? TransactionType.SELL : TransactionType.TRANSFER;
        if (from != owner() && to != owner() && to != ZERO && to != DEAD && !_swapping) {
            require(!_isBlacklisted[from] && !_isBlacklisted[to], "Blacklisted.");

            if(!tradingOpen) require(_isExcludedFromFees[from] || _isExcludedFromFees[to], "Trading is not allowed yet.");

            if (cooldownEnabled) {
                if (to != address(_dexRouter) && to != address(_dexPair)) {
                    require(_cooldown[tx.origin] < block.number - _cooldownBlocks && _cooldown[to] < block.number - _cooldownBlocks, "Transfer delay enabled. Try again later.");
                    _cooldown[tx.origin] = block.number;
                    _cooldown[to] = block.number;
                }
            }

            if (txType == TransactionType.BUY && to != address(_dexRouter) && !_isExcludedMaxTransactionAmount[to]) {
                
                require(amount <= maxBuyAmount, "Transfer amount exceeds the maxBuyAmount.");
                require(balanceOf(to) + amount <= maxWalletAmount, "Exceeds maximum wallet token amount.");
            }
            
            if (txType == TransactionType.SELL && from != address(_dexRouter) && !_isExcludedMaxTransactionAmount[from]) require(amount <= maxSellAmount, "Transfer amount exceeds the maxSellAmount.");
        }

        if(_isExcludedFromFees[from] || _isExcludedFromFees[to] || !feesEnabled || (!transferFeesEnabled && txType == TransactionType.TRANSFER)) takeFee = false;

        uint256 contractBalance = balanceOf(address(this));
        bool canSwap = (contractBalance > _swapTokensAtAmount) && (txType == TransactionType.SELL);

        if (canSwap && swapEnabled && !_swapping && !_isExcludedFromFees[from] && !_isExcludedFromFees[to]) {
            _swapping = true;
            _swapBack(contractBalance);
            _swapping = false;
        }

        _tokenTransfer(from, to, amount, takeFee, txType);
    }

    function _swapBack(uint256 contractBalance) internal {
        uint256 totalTokensToSwap =  _tokensForMarketing.add(_tokensFornonKycCEX).add(_tokensForLiquidity);
        bool success;
        
        if (contractBalance == 0 || totalTokensToSwap == 0) return;

        if (contractBalance > _swapTokensAtAmount.mul(5)) contractBalance = _swapTokensAtAmount.mul(5);

        uint256 liquidityTokens = contractBalance.mul(_tokensForLiquidity).div(totalTokensToSwap).div(2);
        uint256 amountToSwapForETH = contractBalance.sub(liquidityTokens);

        uint256 initialETHBalance = address(this).balance;

        _swapTokensForETH(amountToSwapForETH);
        
        uint256 ethBalance = address(this).balance.sub(initialETHBalance);
        uint256 ethForMktg = ethBalance.mul(_tokensForMarketing).div(totalTokensToSwap);
        uint256 ethForDev = ethBalance.mul(_tokensFornonKycCEX).div(totalTokensToSwap);
        uint256 ethForLiq = ethBalance.sub(ethForMktg).sub(ethForDev);
        
        _tokensForMarketing = 0;
        _tokensFornonKycCEX = 0;
        _tokensForLiquidity = 0;

        if(liquidityTokens > 0 && ethForLiq > 0) _addLiquidity(liquidityTokens, ethForLiq);

        (success,) = address(nonkycCEXWalletAddress).call{value: ethForDev}("");
        (success,) = address(marketingWalletAddress).call{value: address(this).balance}("");
    }

    function _swapTokensForETH(uint256 tokenAmount) internal {
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = _dexRouter.WETH();
        _approve(address(this), address(_dexRouter), tokenAmount);
        _dexRouter.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0,
            path,
            address(this),
            block.timestamp
        );
    }

    function _addLiquidity(uint256 tokenAmount, uint256 ethAmount) internal {
        _approve(address(this), address(_dexRouter), tokenAmount);
        _dexRouter.addLiquidityETH{value: ethAmount}(
            address(this),
            tokenAmount,
            0,
            0,
            liquidityWalletAddress,
            block.timestamp
        );
    }
        
    function _sendETHToFee(uint256 amount) internal {
        marketingWalletAddress.transfer(amount.div(2));
        nonkycCEXWalletAddress.transfer(amount.div(2));
    }

    function openTrading(uint256 blocks) public onlyOwner {
        require(!tradingOpen, "Trading is already open");
        require(blocks <= 10, "Invalid blocks count.");

        if (block.chainid == 1 || block.chainid == 5) _dexRouter = IDEXRouter(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D); // ETH: Uniswap V2
        else if (block.chainid == 56) _dexRouter = IDEXRouter(0x10ED43C718714eb63d5aA57B78B54704E256024E); // ETH Chain: PCS V2
        else if (block.chainid == 97) _dexRouter = IDEXRouter(0xD99D1c33F9fC3444f8101754aBC46c52416550D1); // ETH Chain Testnet: PCS V2
        else if (block.chainid == 137 || block.chainid == 80001) _dexRouter = IDEXRouter(0xa5E0829CaCEd8fFDD4De3c43696c57F7D7A678ff); // Polygon: Quickswap 
        else revert("Chain not set.");

        _approve(address(this), address(_dexRouter), totalSupply());
        _dexPair = IDEXFactory(_dexRouter.factory()).createPair(address(this), _dexRouter.WETH());
        _dexRouter.addLiquidityETH{value: address(this).balance}(address(this), balanceOf(address(this)), 0, 0, owner(), block.timestamp);
        IERC20(_dexPair).approve(address(_dexRouter), type(uint).max);

        maxBuyAmount = totalSupply().mul(2).div(1000);
        maxSellAmount = totalSupply().mul(2).div(1000);
        maxWalletAmount = totalSupply().mul(1).div(100);
        _swapTokensAtAmount = totalSupply().mul(2).div(10000);
        swapEnabled = true;
        cooldownEnabled = true;
        tradingOpen = true;
        tradingOpenBlock = block.number;
        _blocksToBlacklist = blocks;
        emit OpenTrading(tradingOpenBlock, _blocksToBlacklist);
    }


    function isBlacklisted(address wallet) external view returns (bool) {
        return _isBlacklisted[wallet];
    }

   

    function changeSwapEnabled(bool onoff) public onlyOwner {
        swapEnabled = onoff;
    }


 function changeFeesEnabled(bool onoff) public onlyOwner {
        feesEnabled = onoff;
    }

     function changeTransferFeesEnabled(bool onoff) public onlyOwner {
        transferFeesEnabled = onoff;
    }

    function changeCooldownEnabled(bool onoff) public onlyOwner {
        cooldownEnabled = onoff;
    }
   

    function setMaxBuyAmount(uint256 _maxBuyAmount) public onlyOwner {
        require(_maxBuyAmount >= (totalSupply().mul(1).div(1000)), "Max buy amount cannot be lower than 0.1% total supply.");
        maxBuyAmount = _maxBuyAmount;
        emit SetMaxBuyAmount(maxBuyAmount);
    }

    function setMaxSellAmount(uint256 _maxSellAmount) public onlyOwner {
        require(_maxSellAmount >= (totalSupply().mul(1).div(1000)), "Max sell amount cannot be lower than 0.1% total supply.");
        maxSellAmount = _maxSellAmount;
        emit SetMaxSellAmount(maxSellAmount);
    }
    
    function setMaxWalletAmount(uint256 _maxWalletAmount) public onlyOwner {
        require(_maxWalletAmount >= (totalSupply().mul(1).div(1000)), "Max wallet amount cannot be lower than 0.1% total supply.");
        maxWalletAmount = _maxWalletAmount;
        emit SetMaxWalletAmount(maxWalletAmount);
    }
    
    function setSwapTokensAtAmount(uint256 swapTokensAtAmount) public onlyOwner {
        require(swapTokensAtAmount >= (totalSupply().mul(1).div(1000000)), "Swap amount cannot be lower than 0.0001% total supply.");
        require(swapTokensAtAmount <= (totalSupply().mul(5).div(1000)), "Swap amount cannot be higher than 0.5% total supply.");
        _swapTokensAtAmount = swapTokensAtAmount;
        emit SetSwapTokensAtAmount(_swapTokensAtAmount);
    }

    function setMarketingWallet(address _marketingWalletAddress) public onlyOwner {
        require(_marketingWalletAddress != ZERO, "marketingWalletAddress cannot be 0");
        _isExcludedFromFees[marketingWalletAddress] = false;
        _isExcludedMaxTransactionAmount[marketingWalletAddress] = false;
        marketingWalletAddress = payable(_marketingWalletAddress);
        _isExcludedFromFees[marketingWalletAddress] = true;
        _isExcludedMaxTransactionAmount[marketingWalletAddress] = true;
    }

    function setnonKycCEXWallet(address _nonkycCEXWalletAddress) public onlyOwner {
        require(_nonkycCEXWalletAddress != ZERO, "nonkycCEXWalletAddress cannot be 0");
        _isExcludedFromFees[nonkycCEXWalletAddress] = false;
        _isExcludedMaxTransactionAmount[nonkycCEXWalletAddress] = false;
        nonkycCEXWalletAddress = payable(_nonkycCEXWalletAddress);
        _isExcludedFromFees[nonkycCEXWalletAddress] = true;
        _isExcludedMaxTransactionAmount[nonkycCEXWalletAddress] = true;
    }

    function setLiquidityWallet(address _liquidityWalletAddress) public onlyOwner {
        require(_liquidityWalletAddress != ZERO, "liquidityWalletAddress cannot be 0");
        _isExcludedFromFees[liquidityWalletAddress] = false;
        _isExcludedMaxTransactionAmount[liquidityWalletAddress] = false;
        liquidityWalletAddress = payable(_liquidityWalletAddress);
        _isExcludedFromFees[liquidityWalletAddress] = true;
        _isExcludedMaxTransactionAmount[liquidityWalletAddress] = true;
    }

    function setExcludedFromFees(address[] memory accounts, bool isEx) public onlyOwner {
        for (uint i = 0; i < accounts.length; i++) _isExcludedFromFees[accounts[i]] = isEx;
    }
    
    function setExcludeFromMaxTransaction(address[] memory accounts, bool isEx) public onlyOwner {
        for (uint i = 0; i < accounts.length; i++) _isExcludedMaxTransactionAmount[accounts[i]] = isEx;
    }
    
    function setBlacklist(address[] memory accounts, bool isBL) public onlyOwner {
        for (uint i = 0; i < accounts.length; i++) {
            if((accounts[i] != _dexPair) && (accounts[i] != address(_dexRouter)) && (accounts[i] != address(this))) _isBlacklisted[accounts[i]] = isBL;
        }
    }

    function setBuyFee(uint256 _buyMarketingFee, uint256 _buynonkycCEXFee, uint256 _buyLiquidityFee) public onlyOwner {
        buyMarketingFee = _buyMarketingFee;
        buynonkycCEXFee = _buynonkycCEXFee;
        buyLiquidityFee = _buyLiquidityFee;
        emit SetBuyFee(buyMarketingFee, buynonkycCEXFee, buyLiquidityFee);
    }

    function setSellFee(uint256 _sellMarketingFee, uint256 _sellnonKycCEXFee, uint256 _sellLiquidityFee) public onlyOwner {
        sellMarketingFee = _sellMarketingFee;
        sellnonKycCEXFee = _sellnonKycCEXFee;
        sellLiquidityFee = _sellLiquidityFee;
        emit SetSellFee(sellMarketingFee, sellnonKycCEXFee, sellLiquidityFee);
    }

    function setTransferFee(uint256 _transferMarketingFee, uint256 _transfernonKycCEXFee, uint256 _transferLiquidityFee) public onlyOwner {
        transferMarketingFee = _transferMarketingFee;
        transfernonKycCEXFee = _transfernonKycCEXFee;
        transferLiquidityFee = _transferLiquidityFee;
        emit SetTransferFee(transferMarketingFee, transfernonKycCEXFee, transferLiquidityFee);
    }

    function setCooldownBlocks(uint256 blocks) public onlyOwner {
        require(blocks <= 10, "Invalid blocks count.");
        _cooldownBlocks = blocks;
    }

    function _removeAllFee() internal {
        if (buyMarketingFee == 0 && buynonkycCEXFee == 0 && buyLiquidityFee == 0 && 
        sellMarketingFee == 0 && sellnonKycCEXFee == 0 && sellLiquidityFee == 0 &&
        transferMarketingFee == 0 && transfernonKycCEXFee == 0 && transferLiquidityFee == 0) return;

        _previousBuyMarketingFee = buyMarketingFee;
        _previousBuynonKycCEXFee = buynonkycCEXFee;
        _previousBuyLiquidityFee = buyLiquidityFee;
        _previousSellMktgFee = sellMarketingFee;
        _previousSellDevFee = sellnonKycCEXFee;
        _previousSellLiqFee = sellLiquidityFee;
        _previousTransferMarketingFee = transferMarketingFee;
        _previousTransfernonKycCEXFee = transfernonKycCEXFee;
        _previousTransferLiquidityFee = transferLiquidityFee;
        
        buyMarketingFee = 0;
        buynonkycCEXFee = 0;
        buyLiquidityFee = 0;
        sellMarketingFee = 0;
        sellnonKycCEXFee = 0;
        sellLiquidityFee = 0;
        transferMarketingFee = 0;
        transfernonKycCEXFee = 0;
        transferLiquidityFee = 0;
    }
    
    function _restoreAllFee() internal {
        buyMarketingFee = _previousBuyMarketingFee;
        buynonkycCEXFee = _previousBuynonKycCEXFee;
        buyLiquidityFee = _previousBuyLiquidityFee;
        sellMarketingFee = _previousSellMktgFee;
        sellnonKycCEXFee = _previousSellDevFee;
        sellLiquidityFee = _previousSellLiqFee;
        transferMarketingFee = _previousTransferMarketingFee;
        transfernonKycCEXFee = _previousTransfernonKycCEXFee;
        transferLiquidityFee = _previousTransferLiquidityFee;
    }
        
    function _tokenTransfer(address sender, address recipient, uint256 amount, bool takeFee, TransactionType txType) internal {
        if (!takeFee) _removeAllFee();
        else amount = _takeFees(sender, amount, txType);

        super._transfer(sender, recipient, amount);
        
        if (!takeFee) _restoreAllFee();
    }

    function _takeFees(address sender, uint256 amount, TransactionType txType) internal returns (uint256) {
        if(tradingOpenBlock + _blocksToBlacklist >= block.number) _setBotFees();
        else if (txType == TransactionType.SELL) _setSellFees();
        else if (txType == TransactionType.BUY) _setBuyFees();
        else if (txType == TransactionType.TRANSFER) _setTransferFees();
        else revert("Invalid transaction type.");
        
        uint256 fees;
        if (_totalFees > 0) {
            fees = amount.mul(_totalFees).div(FEE_DIVISOR);
            _tokensForMarketing += fees * _marketingFee / _totalFees;
            _tokensFornonKycCEX += fees * _nonkycCEXFee / _totalFees;
            _tokensForLiquidity += fees * _liquidityFee / _totalFees;
        }

        if (fees > 0) super._transfer(sender, address(this), fees);

        return amount -= fees;
    }

    function _setBotFees() internal {
        _marketingFee = 333;
        _nonkycCEXFee = 333;
        _liquidityFee = 333;
        _totalFees = _marketingFee.add(_nonkycCEXFee).add(_liquidityFee);
    }

    function _setSellFees() internal {
        _marketingFee = sellMarketingFee;
        _nonkycCEXFee = sellnonKycCEXFee;
        _liquidityFee = sellLiquidityFee;
        _totalFees = _marketingFee.add(_nonkycCEXFee).add(_liquidityFee);
    }

    function _setBuyFees() internal {
        _marketingFee = buyMarketingFee;
        _nonkycCEXFee = buynonkycCEXFee;
        _liquidityFee = buyLiquidityFee;
        _totalFees = _marketingFee.add(_nonkycCEXFee).add(_liquidityFee);
    }

    function _setTransferFees() internal {
        _marketingFee = transferMarketingFee;
        _nonkycCEXFee = transfernonKycCEXFee;
        _liquidityFee = transferLiquidityFee;
        _totalFees = _marketingFee.add(_nonkycCEXFee).add(_liquidityFee);
    }

    function manualDistributeFees() public onlyOwner {
        uint256 contractETHBalance = address(this).balance;
        _sendETHToFee(contractETHBalance);
    }

    function withdrawStuckETH() public onlyOwner {
        bool success;
        (success,) = address(msg.sender).call{value: address(this).balance}("");
    }

    function withdrawStuckERCTokens(address token) public onlyOwner {
        require(token != address(this), "Cannot withdraw own token");
        require(IERC20(token).balanceOf(address(this)) > 0, "No tokens");
        uint amount = IERC20(token).balanceOf(address(this));
        IERC20(token).transfer(msg.sender, amount);
    }

    function removeAllLimits() public onlyOwner {
        maxBuyAmount = totalSupply() * 1;
        maxSellAmount = totalSupply() * 1;
        maxWalletAmount = totalSupply() * 1;
        cooldownEnabled = false;
    }

    receive() external payable {}
    fallback() external payable {}

}