Nova DAO

// SPDX-License-Identifier: MIT
// Contract published on behalf of Nova DAO LLC for NovaDAO.
// This contract is provided as-is without any warranties or guarantees.

/*
 * Nova DAO
 * https://novadao.io
 * Telegram: https://t.me/Nova
 * Warpcast: https://warpcast.com/~/channel/nova
 * X/Twitter: https://x.com/0xNovaDAO
 */


// File: @uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router01.sol

pragma solidity >=0.6.2;

interface IUniswapV2Router01 {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB, uint liquidity);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountToken, uint amountETH);
    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETHWithPermit(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountToken, uint amountETH);
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);
    function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);

    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
    function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}

// File: @uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol

pragma solidity >=0.6.2;


interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountETH);
    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountETH);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}

// File: @uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol

pragma solidity >=0.5.0;

interface IUniswapV2Factory {
    event PairCreated(address indexed token0, address indexed token1, address pair, uint);

    function feeTo() external view returns (address);
    function feeToSetter() external view returns (address);

    function getPair(address tokenA, address tokenB) external view returns (address pair);
    function allPairs(uint) external view returns (address pair);
    function allPairsLength() external view returns (uint);

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

    function setFeeTo(address) external;
    function setFeeToSetter(address) external;
}

// File: @openzeppelin/contracts/utils/Context.sol


// 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;
    }
}

// File: @openzeppelin/contracts/access/Ownable.sol


// 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);
    }
}

// File: TimeLock.sol


pragma solidity 0.8.16;


/*
* @dev Implementation of a simple timelock mechanism for protecting high-security functions.
*
* The modifier withTimelock(functionName) can be added to any function, ensuring any use
* is preceeded by a 24hr wait period, and an appropriate event emission. Following execution
* of the function, the lock will be automatically re-applied.
*/

contract TimeLock is Ownable {
    uint256 public constant lockDuration = 24 hours;

    mapping(bytes32 => uint256) public unlockTimestamps;

    event FunctionUnlocked(bytes32 indexed functionIdentifier, uint256 unlockTimestamp);

    modifier withTimelock(string memory functionName) {
        bytes32 functionIdentifier = keccak256(bytes(functionName));
        require(unlockTimestamps[functionIdentifier] != 0, "Function is locked");
        require(block.timestamp >= unlockTimestamps[functionIdentifier], "Timelock is active");
        _;
        lockFunction(functionName);
    }

    function unlockFunction(string memory functionName) public onlyOwner {
        bytes32 functionIdentifier = keccak256(bytes(functionName));
        uint256 unlockTimestamp = block.timestamp + lockDuration;
        unlockTimestamps[functionIdentifier] = unlockTimestamp;
        emit FunctionUnlocked(functionIdentifier, unlockTimestamp);
    }

    function lockFunction(string memory functionName) internal {
        bytes32 functionIdentifier = keccak256(bytes(functionName));
        unlockTimestamps[functionIdentifier] = 0;
    }
}
// File: @openzeppelin/contracts/token/ERC20/IERC20.sol


// 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);
}

// File: @openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol


// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)

pragma solidity ^0.8.0;


/**
 * @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);
}

// File: @openzeppelin/contracts/token/ERC20/ERC20.sol


// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/ERC20.sol)

pragma solidity ^0.8.0;




/**
 * @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 {}
}

// File: @openzeppelin/contracts/token/ERC20/extensions/ERC20Burnable.sol


// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/extensions/ERC20Burnable.sol)

pragma solidity ^0.8.0;



/**
 * @dev Extension of {ERC20} that allows token holders to destroy both their own
 * tokens and those that they have an allowance for, in a way that can be
 * recognized off-chain (via event analysis).
 */
abstract contract ERC20Burnable is Context, ERC20 {
    /**
     * @dev Destroys `amount` tokens from the caller.
     *
     * See {ERC20-_burn}.
     */
    function burn(uint256 amount) public virtual {
        _burn(_msgSender(), amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, deducting from the caller's
     * allowance.
     *
     * See {ERC20-_burn} and {ERC20-allowance}.
     *
     * Requirements:
     *
     * - the caller must have allowance for ``accounts``'s tokens of at least
     * `amount`.
     */
    function burnFrom(address account, uint256 amount) public virtual {
        _spendAllowance(account, _msgSender(), amount);
        _burn(account, amount);
    }
}

// File: IERC165.sol
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC165 standard, as defined in the
 * https://eips.ethereum.org/EIPS/eip-165[EIP].
 *
 * Implementers can declare support of contract interfaces, which can then be
 * queried by others ({ERC165Checker}).
 *
 * For an implementation, see {ERC165}.
 */
interface IERC165 {
    /**
     * @dev Returns true if this contract implements the interface defined by
     * `interfaceId`. See the corresponding
     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
     * to learn more about how these ids are created.
     *
     * This function call must use less than 30 000 gas.
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);
}

//file: Semver.sol
pragma solidity ^0.8.0;

/**
 * @title Semver
 * @notice Semver is a simple contract for managing contract versions.
 */
contract Semver {
    /**
     * @notice Contract version number (major).
     */
    uint256 private immutable MAJOR_VERSION;

    /**
     * @notice Contract version number (minor).
     */
    uint256 private immutable MINOR_VERSION;

    /**
     * @notice Contract version number (patch).
     */
    uint256 private immutable PATCH_VERSION;

    /**
     * @param _major Version number (major).
     * @param _minor Version number (minor).
     * @param _patch Version number (patch).
     */
    constructor(
        uint256 _major,
        uint256 _minor,
        uint256 _patch
    ) {
        MAJOR_VERSION = _major;
        MINOR_VERSION = _minor;
        PATCH_VERSION = _patch;
    }

    /**
     * @notice Returns the full semver contract version.
     *
     * @return Semver contract version as a string.
     */
    function version() public view returns (string memory) {
        return
            string(
                abi.encodePacked(
                    Strings.toString(MAJOR_VERSION),
                    ".",
                    Strings.toString(MINOR_VERSION),
                    ".",
                    Strings.toString(PATCH_VERSION)
                )
            );
    }
}

// File: Strings.sol
// OpenZeppelin Contracts (last updated v4.7.0) (utils/Strings.sol)

pragma solidity ^0.8.0;

/**
 * @dev String operations.
 */
library Strings {
    bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
    uint8 private constant _ADDRESS_LENGTH = 20;

    /**
     * @dev Converts a `uint256` to its ASCII `string` decimal representation.
     */
    function toString(uint256 value) internal pure returns (string memory) {
        // Inspired by OraclizeAPI's implementation - MIT licence
        // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol

        if (value == 0) {
            return "0";
        }
        uint256 temp = value;
        uint256 digits;
        while (temp != 0) {
            digits++;
            temp /= 10;
        }
        bytes memory buffer = new bytes(digits);
        while (value != 0) {
            digits -= 1;
            buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
            value /= 10;
        }
        return string(buffer);
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        if (value == 0) {
            return "0x00";
        }
        uint256 temp = value;
        uint256 length = 0;
        while (temp != 0) {
            length++;
            temp >>= 8;
        }
        return toHexString(value, length);
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
     */
    function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
        bytes memory buffer = new bytes(2 * length + 2);
        buffer[0] = "0";
        buffer[1] = "x";
        for (uint256 i = 2 * length + 1; i > 1; --i) {
            buffer[i] = _HEX_SYMBOLS[value & 0xf];
            value >>= 4;
        }
        require(value == 0, "Strings: hex length insufficient");
        return string(buffer);
    }

    /**
     * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
     */
    function toHexString(address addr) internal pure returns (string memory) {
        return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
    }
}

// File: IOptimismMintableERC20.sol

pragma solidity ^0.8.0;

/**
 * @title IOptimismMintableERC20
 * @notice This interface is available on the OptimismMintableERC20 contract. We declare it as a
 *         separate interface so that it can be used in custom implementations of
 *         OptimismMintableERC20.
 */
interface IOptimismMintableERC20 is IERC165 {
    function remoteToken() external returns (address);

    function bridge() external returns (address);

    function mint(address _to, uint256 _amount) external;

    function burn(address _from, uint256 _amount) external;
}

/**
 * @custom:legacy
 * @title ILegacyMintableERC20
 * @notice This interface was available on the legacy L2StandardERC20 contract. It remains available
 *         on the OptimismMintableERC20 contract for backwards compatibility.
 */
interface ILegacyMintableERC20 is IERC165 {
    function l1Token() external returns (address);

    function mint(address _to, uint256 _amount) external;

    function burn(address _from, uint256 _amount) external;
}

// File: Nova.sol
pragma solidity 0.8.16;

contract Nova is ERC20, Ownable, TimeLock, IOptimismMintableERC20, ILegacyMintableERC20, Semver {
    string constant private _name = "Nova DAO";
    string constant private _symbol = "NOVA";
    uint256 constant private _decimals = 18;
    address constant public DEAD = 0x000000000000000000000000000000000000dEaD;
    
    address public daoWallet;
    uint256 public allowedSlippage = 0;
    uint256 public taxForLiquidity = 0;
    uint256 public taxForDao = 0;
    uint256 public _daoReserves = 0;
    uint256 public numTokensSellToAddToLiquidity = 10000 * 10**_decimals;
    uint256 public numTokensSellToAddToETH = 5000 * 10**_decimals;

    mapping(address => bool) public isExcludedFromFee;
    mapping(address => bool) public isLiquidityPair;

    event PrimaryRouterPairUpdated(address _router, address _pair);
    event AddedLiquidityPair(address _pair, bool _status);
    event ExcludedFromFeeUpdated(address _address, bool _status);
    event TaxAmountsUpdated(uint _liquidity, uint _dao);
    event DaoWalletUpdated(address _address);
    event SwapThresholdsChanged(uint _lpSwapThreshold, uint _daoSwapThreshold);
    event DaoTransferFailed(address _daoWallet, uint _amount);
    
    IUniswapV2Router02 public uniswapV2Router;
    address public uniswapV2Pair;
    
    bool inSwapAndLiquify;

    event SwapAndLiquify(
        uint256 tokensSwapped,
        uint256 ethReceived,
        uint256 tokensIntoLiqudity
    );

    modifier lockTheSwap() {
        inSwapAndLiquify = true;
        _;
        inSwapAndLiquify = false;
    }

    constructor(address _router, address _daoWallet, address _bridge, address _remoteToken) 
    ERC20(_name, _symbol)
    Semver(1, 0, 0)
    {
        require(_router != DEAD && _router != address(0), "Router cannot be the Dead address, or 0!");
        require(_daoWallet != DEAD && _daoWallet != address(0), "DAO Wallet cannot be the Dead address, or 0!");
        IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(_router);
        uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory()).createPair(address(this), _uniswapV2Router.WETH());
        
        uniswapV2Router = _uniswapV2Router;
        daoWallet = address(_daoWallet);
        REMOTE_TOKEN = _remoteToken;
        BRIDGE = _bridge;

        _approve(address(this), address(uniswapV2Router), type(uint256).max);
        isExcludedFromFee[address(uniswapV2Router)] = true;
        isExcludedFromFee[msg.sender] = true;
        isExcludedFromFee[daoWallet] = true;
        isLiquidityPair[uniswapV2Pair] = true;
    }

    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");
        require(balanceOf(from) >= amount, "ERC20: transfer amount exceeds balance");

        if ((isLiquidityPair[from] || isLiquidityPair[to]) 
        && taxForDao + taxForLiquidity > 0 
        && !inSwapAndLiquify) {
            bool _isSendingDaoTokens = false;

            if (!isLiquidityPair[from]) {
                uint256 contractLiquidityBalance = balanceOf(address(this)) - _daoReserves;
                if (contractLiquidityBalance >= numTokensSellToAddToLiquidity) {
                    _swapAndLiquify(numTokensSellToAddToLiquidity);
                }
                if (_daoReserves >= numTokensSellToAddToETH) {
                    _swapTokensForEth(numTokensSellToAddToETH);
                    _daoReserves -= numTokensSellToAddToETH;
                    _isSendingDaoTokens = true;
                }
            }

            uint256 transferAmount;
            if (isExcludedFromFee[from] || isExcludedFromFee[to]) {
                transferAmount = amount;
            }
            else {
                uint256 daoShare = ((amount * taxForDao) / 100);
                uint256 liquidityShare = ((amount * taxForLiquidity) / 100);
                transferAmount = amount - (daoShare + liquidityShare);
                _daoReserves += daoShare;

                super._transfer(from, address(this), (daoShare + liquidityShare));
            }
            super._transfer(from, to, transferAmount);

            if (_isSendingDaoTokens) {
                (bool success, ) = payable(daoWallet).call{value: address(this).balance}("");
                if(!success) {
                    emit DaoTransferFailed(daoWallet, address(this).balance);
                }
            }
        } 
        else {
            super._transfer(from, to, amount);
        }
    }

    function _swapAndLiquify(uint256 contractTokenBalance) private lockTheSwap {
        uint256 half = (contractTokenBalance / 2);
        uint256 otherHalf = (contractTokenBalance - half);

        uint256 initialBalance = address(this).balance;

        _swapTokensForEth(half);

        uint256 newBalance = (address(this).balance - initialBalance);

        _addLiquidity(otherHalf, newBalance);

        emit SwapAndLiquify(half, newBalance, otherHalf);
    }

    function _swapTokensForEth(uint256 tokenAmount) private lockTheSwap {
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = uniswapV2Router.WETH();
        
        uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0,
            path,
            address(this),
            block.timestamp
        );
    }

    function _addLiquidity(uint256 tokenAmount, uint256 ethAmount) private lockTheSwap {
        uniswapV2Router.addLiquidityETH{value: ethAmount}(
            address(this),
            tokenAmount,
            0,
            0,
            daoWallet,
            block.timestamp
        );
    }

    function updateRouter(address _router) external onlyOwner withTimelock("updateRouterPair") {
        require(_router != DEAD && _router != address(0), "Router cannot be the Dead address, or 0!");

        IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(_router);
        address _pair = IUniswapV2Factory(_uniswapV2Router.factory())
            .getPair(address(this), _uniswapV2Router.WETH());

        require(_pair != DEAD && _pair != address(0), "Pair cannot be the Dead address, or 0!");

        uniswapV2Pair = _pair;
        uniswapV2Router = _uniswapV2Router;

        isExcludedFromFee[address(uniswapV2Router)] = true;
        isLiquidityPair[uniswapV2Pair] = true;

        _approve(address(this), address(uniswapV2Router), type(uint256).max);
        emit PrimaryRouterPairUpdated(_router, _pair);
    }

    function changeDaoWallet(address newWallet) external onlyOwner
    {
        require(newWallet != DEAD && newWallet != address(0), "DAO Wallet cannot be the Dead address, or 0!");
        daoWallet = newWallet;
        emit DaoWalletUpdated(daoWallet);
    }

    function changeTaxForLiquidityAndDao(uint256 _taxForLiquidity, uint256 _taxForDao) 
        external
        onlyOwner
        withTimelock("changeTaxForLiquidityAndDao")
    {
        require((_taxForLiquidity+_taxForDao) <= 6, "ERC20: total tax must not be greater than 6%");
        taxForLiquidity = _taxForLiquidity;
        taxForDao = _taxForDao;
        emit TaxAmountsUpdated(taxForLiquidity, taxForDao);
    }

    function changeSwapThresholds(uint256 _numTokensSellToAddToLiquidity, uint256 _numTokensSellToAddToETH)
        external
        onlyOwner
    {
        require(_numTokensSellToAddToLiquidity < totalSupply() / 100, "Cannot liquidate more than 1% of the supply at once!");
        require(_numTokensSellToAddToETH < totalSupply() / 100, "Cannot liquidate more than 1% of the supply at once!");
        require(_numTokensSellToAddToLiquidity > 0, "LP: Must liquidate at least 1 token.");
        require(_numTokensSellToAddToETH > 0, "ETH/Gas Token: Must liquidate at least 1 token.");
        numTokensSellToAddToLiquidity = _numTokensSellToAddToLiquidity * 10**_decimals;
        numTokensSellToAddToETH = _numTokensSellToAddToETH * 10**_decimals;
        emit SwapThresholdsChanged(numTokensSellToAddToLiquidity, numTokensSellToAddToETH);
    }

    function updatePairStatus(address _pair, bool _status) external onlyOwner {
        require(isContract(_pair), "Address must be a contract");
        isLiquidityPair[_pair] = _status;
        emit AddedLiquidityPair(_pair, _status);
    }

    function excludeFromFee(address _address, bool _status) external onlyOwner {
        isExcludedFromFee[_address] = _status;
        emit ExcludedFromFeeUpdated(_address, _status);
    }

    function isContract(address _addr) internal view returns (bool) {
        uint32 size;
        assembly {
            size := extcodesize(_addr)
        }
        return (size > 0);
    }

    /**
     * Optimism Superbridge functions below
     */

    /**
     * @notice Address of the corresponding version of this token on the remote chain.
     */
    address public immutable REMOTE_TOKEN;

    /**
     * @notice Address of the StandardBridge on this network.
     */
    address public immutable BRIDGE;

    /**
     * @notice Emitted whenever tokens are minted for an account.
     *
     * @param account Address of the account tokens are being minted for.
     * @param amount  Amount of tokens minted.
     */
    event Mint(address indexed account, uint256 amount);

    /**
     * @notice Emitted whenever tokens are burned from an account.
     *
     * @param account Address of the account tokens are being burned from.
     * @param amount  Amount of tokens burned.
     */
    event Burn(address indexed account, uint256 amount);

    /**
     * @notice A modifier that only allows the bridge to call
     */
    modifier onlyBridge() {
        require(msg.sender == BRIDGE, "OptimismMintableERC20: only bridge can mint and burn");
        _;
    }
    

    /**
     * @notice Allows the StandardBridge on this network to mint tokens.
     *
     * @param _to     Address to mint tokens to.
     * @param _amount Amount of tokens to mint.
     */
    function mint(address _to, uint256 _amount)
        external
        virtual
        override(IOptimismMintableERC20, ILegacyMintableERC20)
        onlyBridge
    {
        _mint(_to, _amount);
        emit Mint(_to, _amount);
    }

    /**
     * @notice Allows the StandardBridge on this network to burn tokens.
     *
     * @param _from   Address to burn tokens from.
     * @param _amount Amount of tokens to burn.
     */
    function burn(address _from, uint256 _amount)
        external
        virtual
        override(IOptimismMintableERC20, ILegacyMintableERC20)
        onlyBridge
    {
        _burn(_from, _amount);
        emit Burn(_from, _amount);
    }

    /**
     * @notice ERC165 interface check function.
     *
     * @param _interfaceId Interface ID to check.
     *
     * @return Whether or not the interface is supported by this contract.
     */
    function supportsInterface(bytes4 _interfaceId) external pure returns (bool) {
        bytes4 iface1 = type(IERC165).interfaceId;
        // Interface corresponding to the legacy L2StandardERC20.
        bytes4 iface2 = type(ILegacyMintableERC20).interfaceId;
        // Interface corresponding to the updated OptimismMintableERC20 (this contract).
        bytes4 iface3 = type(IOptimismMintableERC20).interfaceId;
        return _interfaceId == iface1 || _interfaceId == iface2 || _interfaceId == iface3;
    }

    /**
     * @custom:legacy
     * @notice Legacy getter for the remote token. Use REMOTE_TOKEN going forward.
     */
    function l1Token() public view returns (address) {
        return REMOTE_TOKEN;
    }

    /**
     * @custom:legacy
     * @notice Legacy getter for the bridge. Use BRIDGE going forward.
     */
    function l2Bridge() public view returns (address) {
        return BRIDGE;
    }

    /**
     * @custom:legacy
     * @notice Legacy getter for REMOTE_TOKEN.
     */
    function remoteToken() public view returns (address) {
        return REMOTE_TOKEN;
    }

    /**
     * @custom:legacy
     * @notice Legacy getter for BRIDGE.
     */
    function bridge() public view returns (address) {
        return BRIDGE;
    }

    receive() external payable {}
}

{
  "compilationTarget": {
    "Nova.sol": "Nova"
  },
  "evmVersion": "london",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": false,
    "runs": 200
  },
  "remappings": []
}