// File: lib/openzeppelin-contracts/contracts/token/ERC721/IERC721.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC721/IERC721.sol)

pragma solidity ^0.8.0;

import "../../utils/introspection/IERC165.sol";

/**
 * @dev Required interface of an ERC721 compliant contract.
 */
interface IERC721 is IERC165 {
    /**
     * @dev Emitted when `tokenId` token is transferred from `from` to `to`.
     */
    event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);

    /**
     * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
     */
    event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);

    /**
     * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
     */
    event ApprovalForAll(address indexed owner, address indexed operator, bool approved);

    /**
     * @dev Returns the number of tokens in ``owner``'s account.
     */
    function balanceOf(address owner) external view returns (uint256 balance);

    /**
     * @dev Returns the owner of the `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function ownerOf(uint256 tokenId) external view returns (address owner);

    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId,
        bytes calldata data
    ) external;

    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
     * are aware of the ERC721 protocol to prevent tokens from being forever locked.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must have been allowed to move this token by either {approve} or {setApprovalForAll}.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId
    ) external;

    /**
     * @dev Transfers `tokenId` token from `from` to `to`.
     *
     * WARNING: Note that the caller is responsible to confirm that the recipient is capable of receiving ERC721
     * or else they may be permanently lost. Usage of {safeTransferFrom} prevents loss, though the caller must
     * understand this adds an external call which potentially creates a reentrancy vulnerability.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address from,
        address to,
        uint256 tokenId
    ) external;

    /**
     * @dev Gives permission to `to` to transfer `tokenId` token to another account.
     * The approval is cleared when the token is transferred.
     *
     * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
     *
     * Requirements:
     *
     * - The caller must own the token or be an approved operator.
     * - `tokenId` must exist.
     *
     * Emits an {Approval} event.
     */
    function approve(address to, uint256 tokenId) external;

    /**
     * @dev Approve or remove `operator` as an operator for the caller.
     * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
     *
     * Requirements:
     *
     * - The `operator` cannot be the caller.
     *
     * Emits an {ApprovalForAll} event.
     */
    function setApprovalForAll(address operator, bool _approved) external;

    /**
     * @dev Returns the account approved for `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function getApproved(uint256 tokenId) external view returns (address operator);

    /**
     * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
     *
     * See {setApprovalForAll}
     */
    function isApprovedForAll(address owner, address operator) external view returns (bool);
}

// File: lib/openzeppelin-contracts/contracts/utils/introspection/IERC165.sol



// SPDX-License-Identifier: MIT
// 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: lib/openzeppelin-contracts-upgradeable/contracts/access/OwnableUpgradeable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)

pragma solidity ^0.8.0;

import "../utils/ContextUpgradeable.sol";
import "../proxy/utils/Initializable.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 OwnableUpgradeable is Initializable, ContextUpgradeable {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    function __Ownable_init() internal onlyInitializing {
        __Ownable_init_unchained();
    }

    function __Ownable_init_unchained() internal onlyInitializing {
        _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);
    }

    /**
     * @dev This empty reserved space is put in place to allow future versions to add new
     * variables without shifting down storage in the inheritance chain.
     * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
     */
    uint256[49] private __gap;
}

// File: lib/openzeppelin-contracts-upgradeable/contracts/proxy/utils/Initializable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.1) (proxy/utils/Initializable.sol)

pragma solidity ^0.8.2;

import "../../utils/AddressUpgradeable.sol";

/**
 * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
 * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
 * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
 * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
 *
 * The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
 * reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
 * case an upgrade adds a module that needs to be initialized.
 *
 * For example:
 *
 * [.hljs-theme-light.nopadding]
 * ```
 * contract MyToken is ERC20Upgradeable {
 *     function initialize() initializer public {
 *         __ERC20_init("MyToken", "MTK");
 *     }
 * }
 * contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
 *     function initializeV2() reinitializer(2) public {
 *         __ERC20Permit_init("MyToken");
 *     }
 * }
 * ```
 *
 * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
 * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
 *
 * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
 * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
 *
 * [CAUTION]
 * ====
 * Avoid leaving a contract uninitialized.
 *
 * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
 * contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
 * the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
 *
 * [.hljs-theme-light.nopadding]
 * ```
 * /// @custom:oz-upgrades-unsafe-allow constructor
 * constructor() {
 *     _disableInitializers();
 * }
 * ```
 * ====
 */
abstract contract Initializable {
    /**
     * @dev Indicates that the contract has been initialized.
     * @custom:oz-retyped-from bool
     */
    uint8 private _initialized;

    /**
     * @dev Indicates that the contract is in the process of being initialized.
     */
    bool private _initializing;

    /**
     * @dev Triggered when the contract has been initialized or reinitialized.
     */
    event Initialized(uint8 version);

    /**
     * @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
     * `onlyInitializing` functions can be used to initialize parent contracts.
     *
     * Similar to `reinitializer(1)`, except that functions marked with `initializer` can be nested in the context of a
     * constructor.
     *
     * Emits an {Initialized} event.
     */
    modifier initializer() {
        bool isTopLevelCall = !_initializing;
        require(
            (isTopLevelCall && _initialized < 1) || (!AddressUpgradeable.isContract(address(this)) && _initialized == 1),
            "Initializable: contract is already initialized"
        );
        _initialized = 1;
        if (isTopLevelCall) {
            _initializing = true;
        }
        _;
        if (isTopLevelCall) {
            _initializing = false;
            emit Initialized(1);
        }
    }

    /**
     * @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
     * contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
     * used to initialize parent contracts.
     *
     * A reinitializer may be used after the original initialization step. This is essential to configure modules that
     * are added through upgrades and that require initialization.
     *
     * When `version` is 1, this modifier is similar to `initializer`, except that functions marked with `reinitializer`
     * cannot be nested. If one is invoked in the context of another, execution will revert.
     *
     * Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
     * a contract, executing them in the right order is up to the developer or operator.
     *
     * WARNING: setting the version to 255 will prevent any future reinitialization.
     *
     * Emits an {Initialized} event.
     */
    modifier reinitializer(uint8 version) {
        require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
        _initialized = version;
        _initializing = true;
        _;
        _initializing = false;
        emit Initialized(version);
    }

    /**
     * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
     * {initializer} and {reinitializer} modifiers, directly or indirectly.
     */
    modifier onlyInitializing() {
        require(_initializing, "Initializable: contract is not initializing");
        _;
    }

    /**
     * @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
     * Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
     * to any version. It is recommended to use this to lock implementation contracts that are designed to be called
     * through proxies.
     *
     * Emits an {Initialized} event the first time it is successfully executed.
     */
    function _disableInitializers() internal virtual {
        require(!_initializing, "Initializable: contract is initializing");
        if (_initialized < type(uint8).max) {
            _initialized = type(uint8).max;
            emit Initialized(type(uint8).max);
        }
    }

    /**
     * @dev Returns the highest version that has been initialized. See {reinitializer}.
     */
    function _getInitializedVersion() internal view returns (uint8) {
        return _initialized;
    }

    /**
     * @dev Returns `true` if the contract is currently initializing. See {onlyInitializing}.
     */
    function _isInitializing() internal view returns (bool) {
        return _initializing;
    }
}

// File: lib/openzeppelin-contracts-upgradeable/contracts/security/PausableUpgradeable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (security/Pausable.sol)

pragma solidity ^0.8.0;

import "../utils/ContextUpgradeable.sol";
import "../proxy/utils/Initializable.sol";

/**
 * @dev Contract module which allows children to implement an emergency stop
 * mechanism that can be triggered by an authorized account.
 *
 * This module is used through inheritance. It will make available the
 * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
 * the functions of your contract. Note that they will not be pausable by
 * simply including this module, only once the modifiers are put in place.
 */
abstract contract PausableUpgradeable is Initializable, ContextUpgradeable {
    /**
     * @dev Emitted when the pause is triggered by `account`.
     */
    event Paused(address account);

    /**
     * @dev Emitted when the pause is lifted by `account`.
     */
    event Unpaused(address account);

    bool private _paused;

    /**
     * @dev Initializes the contract in unpaused state.
     */
    function __Pausable_init() internal onlyInitializing {
        __Pausable_init_unchained();
    }

    function __Pausable_init_unchained() internal onlyInitializing {
        _paused = false;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is not paused.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    modifier whenNotPaused() {
        _requireNotPaused();
        _;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is paused.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    modifier whenPaused() {
        _requirePaused();
        _;
    }

    /**
     * @dev Returns true if the contract is paused, and false otherwise.
     */
    function paused() public view virtual returns (bool) {
        return _paused;
    }

    /**
     * @dev Throws if the contract is paused.
     */
    function _requireNotPaused() internal view virtual {
        require(!paused(), "Pausable: paused");
    }

    /**
     * @dev Throws if the contract is not paused.
     */
    function _requirePaused() internal view virtual {
        require(paused(), "Pausable: not paused");
    }

    /**
     * @dev Triggers stopped state.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    function _pause() internal virtual whenNotPaused {
        _paused = true;
        emit Paused(_msgSender());
    }

    /**
     * @dev Returns to normal state.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    function _unpause() internal virtual whenPaused {
        _paused = false;
        emit Unpaused(_msgSender());
    }

    /**
     * @dev This empty reserved space is put in place to allow future versions to add new
     * variables without shifting down storage in the inheritance chain.
     * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
     */
    uint256[49] private __gap;
}

// File: lib/openzeppelin-contracts-upgradeable/contracts/utils/AddressUpgradeable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/Address.sol)

pragma solidity ^0.8.1;

/**
 * @dev Collection of functions related to the address type
 */
library AddressUpgradeable {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.

        return account.code.length > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
     * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
     *
     * _Available since v4.8._
     */
    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        if (success) {
            if (returndata.length == 0) {
                // only check isContract if the call was successful and the return data is empty
                // otherwise we already know that it was a contract
                require(isContract(target), "Address: call to non-contract");
            }
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    /**
     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason or using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    function _revert(bytes memory returndata, string memory errorMessage) private pure {
        // Look for revert reason and bubble it up if present
        if (returndata.length > 0) {
            // The easiest way to bubble the revert reason is using memory via assembly
            /// @solidity memory-safe-assembly
            assembly {
                let returndata_size := mload(returndata)
                revert(add(32, returndata), returndata_size)
            }
        } else {
            revert(errorMessage);
        }
    }
}

// File: lib/openzeppelin-contracts-upgradeable/contracts/utils/ContextUpgradeable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^0.8.0;
import "../proxy/utils/Initializable.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 ContextUpgradeable is Initializable {
    function __Context_init() internal onlyInitializing {
    }

    function __Context_init_unchained() internal onlyInitializing {
    }
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

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

    /**
     * @dev This empty reserved space is put in place to allow future versions to add new
     * variables without shifting down storage in the inheritance chain.
     * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
     */
    uint256[50] private __gap;
}

// File: src/Bidder.sol



// SPDX-License-Identifier: GPL-3.0

import "./Doc.sol";
import {OwnableUpgradeable} from "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
import {PausableUpgradeable} from "@openzeppelin/contracts-upgradeable/security/PausableUpgradeable.sol";
import {IERC721} from "openzeppelin-contracts/token/ERC721/IERC721.sol";
import {INounsAuctionHouse} from "./external/interfaces/INounsAuctionHouse.sol";
import {IBidder} from "./IBidder.sol";
import {ENSResolver} from "./ENSResolver.sol";

pragma solidity 0.8.19;

contract Bidder is IBidder, OwnableUpgradeable, PausableUpgradeable {
    /// The name of this contract
    string public constant name = "Federation AutoBidder v0.2";

    /// Base gas to refund
    uint256 public constant REFUND_BASE_GAS = 36000;

    /// Max priority fee used for refunds
    uint256 public constant MAX_REFUND_PRIORITY_FEE = 2 gwei;

    /// Max gas units that will be refunded to a caller
    uint256 public constant MAX_REFUND_GAS_USED = 200_000;

    /// Max base fee to refund a caller
    uint256 public constant MAX_REFUND_BASE_FEE = 200 gwei;

    /// The ERC721 token address that we expect to win at auction
    IERC721 public token;

    /// The last block a bid was placed
    uint256 public lastBidBlock;

    /// The auction house address
    INounsAuctionHouse public auctionHouse;

    // The address for the ENS resolver
    address public ensResolver;

    /// The config for this bidder
    Config internal config;

    /// Do not leave implementation uninitialized
    constructor() {
        _disableInitializers();
    }

    /// Can only be called once
    function initialize(IERC721 t, INounsAuctionHouse ah, address _owner, address _ensResolver, Config memory cfg)
        external
        payable
        initializer
    {
        __Ownable_init();
        __Pausable_init();

        token = t;
        auctionHouse = ah;
        config = cfg;
        ensResolver = _ensResolver;

        if (msg.sender != _owner) {
            _transferOwnership(_owner);
        }
    }

    /// Submit a bid to the auction house
    /// @notice refunds gas and tips the caller
    function bid() external whenNotPaused returns (uint256, uint256) {
        uint256 startGas = gasleft();

        if (lastBidBlock == block.number) {
            revert ExistingBidInBlock();
        }

        (uint256 nounId, uint256 amount,, uint256 endTime, address bidder,) = auctionHouse.auction();

        if (block.timestamp + config.bidWindow < endTime) {
            revert NotInBidWindow();
        }

        if (bidder == address(this)) {
            revert AlreadyHighestBidder();
        }

        uint256 value;
        if (amount > 0) {
            value = amount + ((amount * auctionHouse.minBidIncrementPercentage()) / 100);
        } else {
            value = auctionHouse.reservePrice();
        }

        if (value < config.minBid) {
            value = config.minBid;
        }

        if (value > config.maxBid) {
            revert MaxBidExceeded();
        }

        auctionHouse.createBid{value: value}(nounId);

        emit BidMade(tx.origin, nounId, value);

        lastBidBlock = block.number;

        _refundGasAndTip(startGas);

        return (nounId, value);
    }

    /// Withdraw the given token id from this contract
    /// @notice refunds gas and tips the caller
    function withdraw(uint256 tId) external {
        uint256 startGas = gasleft();

        token.transferFrom(address(this), config.receiver, tId);

        _refundGasAndTip(startGas);
    }

    /// Withdraw contract balance
    function withdrawBalance() external onlyOwner {
        (bool sent,) = owner().call{value: address(this).balance}("");
        require(sent, "failed to withdraw ether");
    }

    /// Handles updating the config for this bidder
    function setConfig(Config calldata cfg) external onlyOwner {
        if (cfg.receiver == address(0)) {
            revert InvalidReceiver();
        }

        config = cfg;
        emit ConfigUpdate(cfg);
    }

    /// Claims an ENS reverse record for this contract address
    /// To remove an existing record call this fn with an empty name
    function setENSReverseRecord(string memory _name) external onlyOwner {
        bytes32 node = ENSResolver(ensResolver).setName(_name);
        emit ENSReverseRecordChanged(node, _name);
    }

    /// Sets the ENS resolver address
    /// Default on mainnet is: 0x084b1c3C81545d370f3634392De611CaaBFf8148
    function setENSResolver(address _resolver) external onlyOwner {
        ensResolver = _resolver;
        emit ENSResolverChanged(_resolver);
    }

    /// Locks the contract to prevent bidding
    function pause() external onlyOwner {
        _pause();
    }

    /// Unlocks the contract to allow bidding
    function unpause() external onlyOwner {
        _unpause();
    }

    /// Returns the config for this bidder
    function getConfig() external view returns (Config memory) {
        return config;
    }

    /// Refunds gas spent on tx to the caller; also provides a tip
    function _refundGasAndTip(uint256 startGas) internal {
        unchecked {
            uint256 balance = address(this).balance;
            if (balance == 0) {
                return;
            }

            uint256 basefee = min(block.basefee, MAX_REFUND_BASE_FEE);
            uint256 gasPrice = min(tx.gasprice, basefee + MAX_REFUND_PRIORITY_FEE);
            uint256 gasUsed = min(startGas - gasleft() + REFUND_BASE_GAS, MAX_REFUND_GAS_USED);
            uint256 refundAmount = min(gasPrice * gasUsed, balance);
            uint256 refundAmountWithTip = min(refundAmount + config.tip, balance);
            (bool refundSent,) = tx.origin.call{value: refundAmountWithTip}("");
            emit GasRefund(tx.origin, refundAmountWithTip, refundSent);
        }
    }

    /// Returns the min of two integers
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }

    /// Can receive ETH
    receive() external payable {}
}

// File: src/Doc.sol



// SPDX-License-Identifier: GPL-3.0

/**
 * @title Federation AutoBidder v0.2
 * @author wiz :- https://twitter.com/0xWiz_
 * @notice A tiny protocol for bidding on Nouns at auction
 *
 * ~~~
 * <<< ⌐◨-◨ >>>
 * https://federation.wtf
 */

pragma solidity 0.8.19;

// File: src/ENSResolver.sol



// SPDX-License-Identifier: GPL-3.0

pragma solidity 0.8.19;

/// Interface for an ENS resolver
interface ENSResolver {
    function setName(string memory) external returns (bytes32);
}

// File: src/IBidder.sol



// SPDX-License-Identifier: GPL-3.0

import {IERC721} from "openzeppelin-contracts/token/ERC721/IERC721.sol";
import {INounsAuctionHouse} from "./external/interfaces/INounsAuctionHouse.sol";

pragma solidity 0.8.19;

interface IBidder {
    /// Returned when a caller attempts to create a bid but this contract
    /// is already the highest bidder
    error AlreadyHighestBidder();

    /// Returned when the owner attempts to withdraw funds but the last auction bid
    /// on has not been settled yet
    error AuctionNotSettled();

    /// Returned when an attempt is made to place a bid that exceeds the max
    /// configurable amount
    error MaxBidExceeded();

    /// Returned when an attempt is made to place a bid outside of the auction
    /// bid window
    error NotInBidWindow();

    /// Returned when updating config that does not have the receiver set
    error InvalidReceiver();

    /// Returned if consecutive bids are made in the same block
    error ExistingBidInBlock();

    /// Emitted when a caller places a bid
    event BidMade(address caller, uint256 tokenId, uint256 amount);

    /// Emitted when a caller receives a gas refund
    event GasRefund(address indexed caller, uint256 refundAmount, bool refundSent);

    /// Emitted when a token is withdrawn
    event Withdraw(address indexed caller, uint256 tokenId);

    /// Emitted when config is updated
    event ConfigUpdate(Config config);

    /// Emitted when an ENS reverse record is claimed by this contract
    event ENSReverseRecordChanged(bytes32 node, string name);

    /// Emitted when the ENS resolver address is changed by the owner
    event ENSResolverChanged(address resolver);

    /// The structure of the config for this bidder
    struct Config {
        /// Max bid that can be placed in an auction
        uint256 maxBid;
        /// Min bid that can be placed in an auction
        uint256 minBid;
        /// Time in seconds a bid can be placed before auction end time
        uint256 bidWindow;
        /// Tip rewarded for caller winning auction
        uint256 tip;
        /// Address that will receive tokens when withdrawn
        address receiver;
    }

    function initialize(IERC721, INounsAuctionHouse, address, address, Config memory) external payable;

    function bid() external returns (uint256, uint256);

    function withdraw(uint256) external;

    function withdrawBalance() external;

    function pause() external;

    function unpause() external;

    function setConfig(Config calldata) external;

    function getConfig() external view returns (Config memory);

    function setENSReverseRecord(string memory) external;

    function setENSResolver(address) external;
}

// File: src/external/interfaces/INounsAuctionHouse.sol



// SPDX-License-Identifier: GPL-3.0

/**
 *
 * ░░░░░░░░░░░░░░░░░░░░░░░░░░░░░ *
 * ░░░░░░░░░░░░░░░░░░░░░░░░░░░░░ *
 * ░░░░░░█████████░░█████████░░░ *
 * ░░░░░░██░░░████░░██░░░████░░░ *
 * ░░██████░░░████████░░░████░░░ *
 * ░░██░░██░░░████░░██░░░████░░░ *
 * ░░██░░██░░░████░░██░░░████░░░ *
 * ░░░░░░█████████░░█████████░░░ *
 * ░░░░░░░░░░░░░░░░░░░░░░░░░░░░░ *
 * ░░░░░░░░░░░░░░░░░░░░░░░░░░░░░ *
 *
 */

pragma solidity 0.8.19;

interface INounsAuctionHouse {
    struct Auction {
        // ID for the Noun (ERC721 token ID)
        uint256 nounId;
        // The current highest bid amount
        uint256 amount;
        // The time that the auction started
        uint256 startTime;
        // The time that the auction is scheduled to end
        uint256 endTime;
        // The address of the current highest bid
        address payable bidder;
        // Whether or not the auction has been settled
        bool settled;
    }

    event AuctionCreated(uint256 indexed nounId, uint256 startTime, uint256 endTime);

    event AuctionBid(uint256 indexed nounId, address sender, uint256 value, bool extended);

    event AuctionExtended(uint256 indexed nounId, uint256 endTime);

    event AuctionSettled(uint256 indexed nounId, address winner, uint256 amount);

    event AuctionTimeBufferUpdated(uint256 timeBuffer);

    event AuctionReservePriceUpdated(uint256 reservePrice);

    event AuctionMinBidIncrementPercentageUpdated(uint256 minBidIncrementPercentage);

    function auction()
        external
        view
        returns (
            uint256 nounId,
            uint256 amount,
            uint256 startTime,
            uint256 endTime,
            address payable bidder,
            bool settled
        );

    function reservePrice() external view returns (uint256);

    function minBidIncrementPercentage() external view returns (uint8);

    function settleAuction() external;

    function settleCurrentAndCreateNewAuction() external;

    function createBid(uint256 nounId) external payable;

    function pause() external;

    function unpause() external;

    function setTimeBuffer(uint256 timeBuffer) external;

    function setReservePrice(uint256 reservePrice) external;

    function setMinBidIncrementPercentage(uint8 minBidIncrementPercentage) external;
}