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// This contract is part of Zellic’s smart contract dataset, which is a collection of publicly available contract code gathered as of March 2023.

// SPDX-License-Identifier: MIT

/*



Bunbuku Chagama is a Japanese fairy tale about a tanuki that uses its shapeshifting powers to reward its rescuer for his kindess.



*/

pragma solidity ^0.8.10;

pragma experimental ABIEncoderV2;

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

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}


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 Returns the address of the current owner.

     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**

     * @dev Throws if called by any account other than the owner.

     */
    modifier onlyOwner() {
        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);
    }
}

////// lib/openzeppelin-contracts/contracts/token/ERC20/IERC20.sol
// OpenZeppelin Contracts v4.4.0 (token/ERC20/IERC20.sol)

/* pragma solidity ^0.8.0; */

/**

 * @dev Interface of the ERC20 standard as defined in the EIP.

 */
interface IERC20 {
    /**

     * @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 `recipient`.

     *

     * Returns a boolean value indicating whether the operation succeeded.

     *

     * Emits a {Transfer} event.

     */
    function transfer(address recipient, 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 `sender` to `recipient` 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 sender,

        address recipient,

        uint256 amount

    ) external returns (bool);

    /**

     * @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);
}

////// lib/openzeppelin-contracts/contracts/token/ERC20/extensions/IERC20Metadata.sol
// OpenZeppelin Contracts v4.4.0 (token/ERC20/extensions/IERC20Metadata.sol)

/* pragma solidity ^0.8.0; */

/* import "../IERC20.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);
}

////// lib/openzeppelin-contracts/contracts/token/ERC20/ERC20.sol
// OpenZeppelin Contracts v4.4.0 (token/ERC20/ERC20.sol)

/* pragma solidity ^0.8.0; */

/* import "./IERC20.sol"; */
/* import "./extensions/IERC20Metadata.sol"; */
/* import "../../utils/Context.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.zeppelin.solutions/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:

     *

     * - `recipient` cannot be the zero address.

     * - the caller must have a balance of at least `amount`.

     */
    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(_msgSender(), recipient, 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}.

     *

     * Requirements:

     *

     * - `spender` cannot be the zero address.

     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        _approve(_msgSender(), 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}.

     *

     * Requirements:

     *

     * - `sender` and `recipient` cannot be the zero address.

     * - `sender` must have a balance of at least `amount`.

     * - the caller must have allowance for ``sender``'s tokens of at least

     * `amount`.

     */
    function transferFrom(

        address sender,

        address recipient,

        uint256 amount

    ) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);

        uint256 currentAllowance = _allowances[sender][_msgSender()];
        require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance");
        unchecked {
            _approve(sender, _msgSender(), currentAllowance - amount);
        }

        return true;
    }

    /**

     * @dev Moves `amount` of tokens from `sender` to `recipient`.

     *

     * 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:

     *

     * - `sender` cannot be the zero address.

     * - `recipient` cannot be the zero address.

     * - `sender` must have a balance of at least `amount`.

     */
    function _transfer(

        address sender,

        address recipient,

        uint256 amount

    ) internal virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(sender, recipient, amount);

        uint256 senderBalance = _balances[sender];
        require(senderBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[sender] = senderBalance - amount;
        }
        _balances[recipient] += amount;

        emit Transfer(sender, recipient, amount);

        _afterTokenTransfer(sender, recipient, 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;
        _balances[account] += amount;
        emit Transfer(address(0), account, amount);

        _afterTokenTransfer(address(0), account, 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 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 {}
}

////// lib/openzeppelin-contracts/contracts/utils/math/SafeMath.sol
// OpenZeppelin Contracts v4.4.0 (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 substraction 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 {
    event PairCreated(

        address indexed token0,

        address indexed token1,

        address pair,

        uint256

    );

    function createPair(address tokenA, address tokenB)
        external
        returns (address pair);
}

interface IUniswapV2Router02 {
    function factory() external pure returns (address);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(

        uint256 amountIn,

        uint256 amountOutMin,

        address[] calldata path,

        address to,

        uint256 deadline

    ) external;
}

contract Chagama is ERC20, Ownable {
    using SafeMath for uint256;

    IUniswapV2Router02 public immutable uniswapV2Router;
    address public immutable uniswapV2Pair;
    address public constant deadAddress = address(0xdead);
    address public USDC = 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48;

    bool private swapping;

    address public devWallet;

    uint256 public maxTransactionAmount;
    uint256 public swapTokensAtAmount;
    uint256 public maxWallet;

    bool public limitsInEffect = true;
    bool public tradingActive = false;
    bool public swapEnabled = false;

    uint256 public buyTotalFees;
    uint256 public buyDevFee;
    uint256 public buyLiquidityFee;

    uint256 public sellTotalFees;
    uint256 public sellDevFee;
    uint256 public sellLiquidityFee;

    /******************/

    // exlcude from fees and max transaction amount
    mapping(address => bool) private _isExcludedFromFees;
    mapping(address => bool) public _isExcludedMaxTransactionAmount;


    event ExcludeFromFees(address indexed account, bool isExcluded);

    event devWalletUpdated(

        address indexed newWallet,

        address indexed oldWallet

    );

    constructor() ERC20("Bunbuku Chagama", "CHAGAMA") {
        IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(

            0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D

        );

        excludeFromMaxTransaction(address(_uniswapV2Router), true);
        uniswapV2Router = _uniswapV2Router;

        uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory())
            .createPair(address(this), USDC);
        excludeFromMaxTransaction(address(uniswapV2Pair), true);


        uint256 _buyDevFee = 2;
        uint256 _buyLiquidityFee = 3;

        uint256 _sellDevFee = 4;
        uint256 _sellLiquidityFee = 1;

        uint256 totalSupply = 700_000_000 * 1e18;

        maxTransactionAmount =  totalSupply * 1 / 100; // 1% from total supply maxTransactionAmountTxn
        maxWallet = totalSupply * 2 / 100; // 2% from total supply maxWallet
        swapTokensAtAmount = (totalSupply * 5) / 10000; // 0.05% swap wallet

        buyDevFee = _buyDevFee;
        buyLiquidityFee = _buyLiquidityFee;
        buyTotalFees = buyDevFee + buyLiquidityFee;

        sellDevFee = _sellDevFee;
        sellLiquidityFee = _sellLiquidityFee;
        sellTotalFees = sellDevFee + sellLiquidityFee;

        devWallet = address(0x95929b28A109732ec4Dd73b1FDB532e069d62b63); // set as dev wallet

        // exclude from paying fees or having max transaction amount
        excludeFromFees(owner(), true);
        excludeFromFees(address(this), true);
        excludeFromFees(address(0xdead), true);

        excludeFromMaxTransaction(owner(), true);
        excludeFromMaxTransaction(address(this), true);
        excludeFromMaxTransaction(address(0xdead), true);

        /*

            _mint is an internal function in ERC20.sol that is only called here,

            and CANNOT be called ever again

        */
        _mint(msg.sender, totalSupply);
    }

    receive() external payable {}

    // once enabled, can never be turned off
    function enableTrading() external onlyOwner {
        tradingActive = true;
        swapEnabled = true;
    }

    // remove limits after token is stable
    function removeLimits() external onlyOwner returns (bool) {
        limitsInEffect = false;
        return true;
    }

    // change the minimum amount of tokens to sell from fees
    function updateSwapTokensAtAmount(uint256 newAmount)
        external
        onlyOwner
        returns (bool)
    {
        require(
            newAmount >= (totalSupply() * 1) / 100000,
            "Swap amount cannot be lower than 0.001% total supply."
        );
        require(
            newAmount <= (totalSupply() * 5) / 1000,
            "Swap amount cannot be higher than 0.5% total supply."
        );
        swapTokensAtAmount = newAmount;
        return true;
    }

    function updateMaxTxnAmount(uint256 newNum) external onlyOwner {
        require(
            newNum >= ((totalSupply() * 1) / 1000) / 1e18,
            "Cannot set maxTransactionAmount lower than 0.1%"
        );
        maxTransactionAmount = newNum * (10**18);
    }

    function updateMaxWalletAmount(uint256 newNum) external onlyOwner {
        require(
            newNum >= ((totalSupply() * 5) / 1000) / 1e18,
            "Cannot set maxWallet lower than 0.5%"
        );
        maxWallet = newNum * (10**18);
    }

    function excludeFromMaxTransaction(address updAds, bool isEx)
        public
        onlyOwner
    {
        _isExcludedMaxTransactionAmount[updAds] = isEx;
    }

    // only use to disable contract sales if absolutely necessary (emergency use only)
    function updateSwapEnabled(bool enabled) external onlyOwner {
        swapEnabled = enabled;
    }

    function updateBuyFees(

        uint256 _devFee,

        uint256 _liquidityFee

    ) external onlyOwner {
        buyDevFee = _devFee;
        buyLiquidityFee = _liquidityFee;
        buyTotalFees = buyDevFee + buyLiquidityFee;
        require(buyTotalFees <= 10, "Must keep fees at 10% or less");
    }

    function updateSellFees(

        uint256 _devFee,

        uint256 _liquidityFee

    ) external onlyOwner {
        sellDevFee = _devFee;
        sellLiquidityFee = _liquidityFee;
        sellTotalFees = sellDevFee + sellLiquidityFee;
        require(sellTotalFees <= 10, "Must keep fees at 10% or less");
    }

    function excludeFromFees(address account, bool excluded) public onlyOwner {
        _isExcludedFromFees[account] = excluded;
        emit ExcludeFromFees(account, excluded);
    }

    function updateDevWallet(address newDevWallet)
        external
        onlyOwner
    {
        emit devWalletUpdated(newDevWallet, devWallet);
        devWallet = newDevWallet;
    }


    function isExcludedFromFees(address account) public view returns (bool) {
        return _isExcludedFromFees[account];
    }

    function _transfer(

        address from,

        address to,

        uint256 amount

    ) internal override {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");

        if (amount == 0) {
            super._transfer(from, to, 0);
            return;
        }

        if (limitsInEffect) {
            if (
                from != owner() &&

                to != owner() &&

                to != address(0) &&

                to != address(0xdead) &&

                !swapping
            ) {
                if (!tradingActive) {
                    require(
                        _isExcludedFromFees[from] || _isExcludedFromFees[to],
                        "Trading is not active."
                    );
                }

                // at launch if the transfer delay is enabled, ensure the block timestamps for purchasers is set -- during launch.
                //when buy
                if (
                    from == uniswapV2Pair &&

                    !_isExcludedMaxTransactionAmount[to]
                ) {
                    require(
                        amount <= maxTransactionAmount,
                        "Buy transfer amount exceeds the maxTransactionAmount."
                    );
                    require(
                        amount + balanceOf(to) <= maxWallet,
                        "Max wallet exceeded"
                    );
                }
                else if (!_isExcludedMaxTransactionAmount[to]) {
                    require(
                        amount + balanceOf(to) <= maxWallet,
                        "Max wallet exceeded"
                    );
                }
            }
        }

        uint256 contractTokenBalance = balanceOf(address(this));

        bool canSwap = contractTokenBalance >= swapTokensAtAmount;

        if (
            canSwap &&

            swapEnabled &&

            !swapping &&

            to == uniswapV2Pair &&

            !_isExcludedFromFees[from] &&

            !_isExcludedFromFees[to]
        ) {
            swapping = true;

            swapBack();

            swapping = false;
        }

        bool takeFee = !swapping;

        // if any account belongs to _isExcludedFromFee account then remove the fee
        if (_isExcludedFromFees[from] || _isExcludedFromFees[to]) {
            takeFee = false;
        }

        uint256 fees = 0;
        uint256 tokensForLiquidity = 0;
        uint256 tokensForDev = 0;
        // only take fees on buys/sells, do not take on wallet transfers
        if (takeFee) {
            // on sell
            if (to == uniswapV2Pair && sellTotalFees > 0) {
                fees = amount.mul(sellTotalFees).div(100);
                tokensForLiquidity = (fees * sellLiquidityFee) / sellTotalFees;
                tokensForDev = (fees * sellDevFee) / sellTotalFees;
            }
            // on buy
            else if (from == uniswapV2Pair && buyTotalFees > 0) {
                fees = amount.mul(buyTotalFees).div(100);
                tokensForLiquidity = (fees * buyLiquidityFee) / buyTotalFees; 
                tokensForDev = (fees * buyDevFee) / buyTotalFees;
            }

            if (fees> 0) {
                super._transfer(from, address(this), fees);
            }
            if (tokensForLiquidity > 0) {
                super._transfer(address(this), uniswapV2Pair, tokensForLiquidity);
            }

            amount -= fees;
        }

        super._transfer(from, to, amount);
    }

    function swapTokensForUSDC(uint256 tokenAmount) private {
        // generate the uniswap pair path of token -> weth
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = USDC;

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

        // make the swap
        uniswapV2Router.swapExactTokensForTokensSupportingFeeOnTransferTokens(

            tokenAmount,

            0, // accept any amount of USDC

            path,

            devWallet,

            block.timestamp

        );
    }

    function swapBack() private {
        uint256 contractBalance = balanceOf(address(this));
        if (contractBalance == 0) {
            return;
        }

        if (contractBalance > swapTokensAtAmount * 20) {
            contractBalance = swapTokensAtAmount * 20;
        }

        swapTokensForUSDC(contractBalance);
    }

}