version

Initialized

previousOwner

newOwner

OwnershipTransferred

owner

renounceOwnership

transferOwnership

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (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. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby disabling 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;
}


// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (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]
 * ```solidity
 * 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;
    }
}


// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (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
     *
     * Furthermore, `isContract` will also return true if the target contract within
     * the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
     * which only has an effect at the end of a transaction.
     * ====
     *
     * [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://consensys.net/diligence/blog/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/v0.8.0/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 Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        (bool success, bytes memory returndata) = target.delegatecall(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);
        }
    }
}


// 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;
}


// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/introspection/ERC165Checker.sol)

pragma solidity ^0.8.0;

import "./IERC165Upgradeable.sol";

/**
 * @dev Library used to query support of an interface declared via {IERC165}.
 *
 * Note that these functions return the actual result of the query: they do not
 * `revert` if an interface is not supported. It is up to the caller to decide
 * what to do in these cases.
 */
library ERC165CheckerUpgradeable {
    // As per the EIP-165 spec, no interface should ever match 0xffffffff
    bytes4 private constant _INTERFACE_ID_INVALID = 0xffffffff;

    /**
     * @dev Returns true if `account` supports the {IERC165} interface.
     */
    function supportsERC165(address account) internal view returns (bool) {
        // Any contract that implements ERC165 must explicitly indicate support of
        // InterfaceId_ERC165 and explicitly indicate non-support of InterfaceId_Invalid
        return
            supportsERC165InterfaceUnchecked(account, type(IERC165Upgradeable).interfaceId) &&
            !supportsERC165InterfaceUnchecked(account, _INTERFACE_ID_INVALID);
    }

    /**
     * @dev Returns true if `account` supports the interface defined by
     * `interfaceId`. Support for {IERC165} itself is queried automatically.
     *
     * See {IERC165-supportsInterface}.
     */
    function supportsInterface(address account, bytes4 interfaceId) internal view returns (bool) {
        // query support of both ERC165 as per the spec and support of _interfaceId
        return supportsERC165(account) && supportsERC165InterfaceUnchecked(account, interfaceId);
    }

    /**
     * @dev Returns a boolean array where each value corresponds to the
     * interfaces passed in and whether they're supported or not. This allows
     * you to batch check interfaces for a contract where your expectation
     * is that some interfaces may not be supported.
     *
     * See {IERC165-supportsInterface}.
     *
     * _Available since v3.4._
     */
    function getSupportedInterfaces(
        address account,
        bytes4[] memory interfaceIds
    ) internal view returns (bool[] memory) {
        // an array of booleans corresponding to interfaceIds and whether they're supported or not
        bool[] memory interfaceIdsSupported = new bool[](interfaceIds.length);

        // query support of ERC165 itself
        if (supportsERC165(account)) {
            // query support of each interface in interfaceIds
            for (uint256 i = 0; i < interfaceIds.length; i++) {
                interfaceIdsSupported[i] = supportsERC165InterfaceUnchecked(account, interfaceIds[i]);
            }
        }

        return interfaceIdsSupported;
    }

    /**
     * @dev Returns true if `account` supports all the interfaces defined in
     * `interfaceIds`. Support for {IERC165} itself is queried automatically.
     *
     * Batch-querying can lead to gas savings by skipping repeated checks for
     * {IERC165} support.
     *
     * See {IERC165-supportsInterface}.
     */
    function supportsAllInterfaces(address account, bytes4[] memory interfaceIds) internal view returns (bool) {
        // query support of ERC165 itself
        if (!supportsERC165(account)) {
            return false;
        }

        // query support of each interface in interfaceIds
        for (uint256 i = 0; i < interfaceIds.length; i++) {
            if (!supportsERC165InterfaceUnchecked(account, interfaceIds[i])) {
                return false;
            }
        }

        // all interfaces supported
        return true;
    }

    /**
     * @notice Query if a contract implements an interface, does not check ERC165 support
     * @param account The address of the contract to query for support of an interface
     * @param interfaceId The interface identifier, as specified in ERC-165
     * @return true if the contract at account indicates support of the interface with
     * identifier interfaceId, false otherwise
     * @dev Assumes that account contains a contract that supports ERC165, otherwise
     * the behavior of this method is undefined. This precondition can be checked
     * with {supportsERC165}.
     *
     * Some precompiled contracts will falsely indicate support for a given interface, so caution
     * should be exercised when using this function.
     *
     * Interface identification is specified in ERC-165.
     */
    function supportsERC165InterfaceUnchecked(address account, bytes4 interfaceId) internal view returns (bool) {
        // prepare call
        bytes memory encodedParams = abi.encodeWithSelector(IERC165Upgradeable.supportsInterface.selector, interfaceId);

        // perform static call
        bool success;
        uint256 returnSize;
        uint256 returnValue;
        assembly {
            success := staticcall(30000, account, add(encodedParams, 0x20), mload(encodedParams), 0x00, 0x20)
            returnSize := returndatasize()
            returnValue := mload(0x00)
        }

        return success && returnSize >= 0x20 && returnValue > 0;
    }
}


interfaceId

supportsInterface

// 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 IERC165Upgradeable {
    /**
     * @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);
}


name_

symbol_

approved

tokenId

Approval

operator

ApprovalForAll

from

Transfer

approve

balanceOf

getApproved

isApprovedForAll

name

ownerOf

safeTransferFrom

data

setApprovalForAll

symbol

tokenURI

transferFrom

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC721/ERC721.sol)

pragma solidity ^0.8.0;

import "./IERC721.sol";
import "./IERC721Receiver.sol";
import "./extensions/IERC721Metadata.sol";
import "../../utils/Address.sol";
import "../../utils/Context.sol";
import "../../utils/Strings.sol";
import "../../utils/introspection/ERC165.sol";

/**
 * @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
 * the Metadata extension, but not including the Enumerable extension, which is available separately as
 * {ERC721Enumerable}.
 */
contract ERC721 is Context, ERC165, IERC721, IERC721Metadata {
    using Address for address;
    using Strings for uint256;

    // Token name
    string private _name;

    // Token symbol
    string private _symbol;

    // Mapping from token ID to owner address
    mapping(uint256 => address) private _owners;

    // Mapping owner address to token count
    mapping(address => uint256) private _balances;

    // Mapping from token ID to approved address
    mapping(uint256 => address) private _tokenApprovals;

    // Mapping from owner to operator approvals
    mapping(address => mapping(address => bool)) private _operatorApprovals;

    /**
     * @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
        return
            interfaceId == type(IERC721).interfaceId ||
            interfaceId == type(IERC721Metadata).interfaceId ||
            super.supportsInterface(interfaceId);
    }

    /**
     * @dev See {IERC721-balanceOf}.
     */
    function balanceOf(address owner) public view virtual override returns (uint256) {
        require(owner != address(0), "ERC721: address zero is not a valid owner");
        return _balances[owner];
    }

    /**
     * @dev See {IERC721-ownerOf}.
     */
    function ownerOf(uint256 tokenId) public view virtual override returns (address) {
        address owner = _ownerOf(tokenId);
        require(owner != address(0), "ERC721: invalid token ID");
        return owner;
    }

    /**
     * @dev See {IERC721Metadata-name}.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }

    /**
     * @dev See {IERC721Metadata-symbol}.
     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    /**
     * @dev See {IERC721Metadata-tokenURI}.
     */
    function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
        _requireMinted(tokenId);

        string memory baseURI = _baseURI();
        return bytes(baseURI).length > 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : "";
    }

    /**
     * @dev Base URI for computing {tokenURI}. If set, the resulting URI for each
     * token will be the concatenation of the `baseURI` and the `tokenId`. Empty
     * by default, can be overridden in child contracts.
     */
    function _baseURI() internal view virtual returns (string memory) {
        return "";
    }

    /**
     * @dev See {IERC721-approve}.
     */
    function approve(address to, uint256 tokenId) public virtual override {
        address owner = ERC721.ownerOf(tokenId);
        require(to != owner, "ERC721: approval to current owner");

        require(
            _msgSender() == owner || isApprovedForAll(owner, _msgSender()),
            "ERC721: approve caller is not token owner or approved for all"
        );

        _approve(to, tokenId);
    }

    /**
     * @dev See {IERC721-getApproved}.
     */
    function getApproved(uint256 tokenId) public view virtual override returns (address) {
        _requireMinted(tokenId);

        return _tokenApprovals[tokenId];
    }

    /**
     * @dev See {IERC721-setApprovalForAll}.
     */
    function setApprovalForAll(address operator, bool approved) public virtual override {
        _setApprovalForAll(_msgSender(), operator, approved);
    }

    /**
     * @dev See {IERC721-isApprovedForAll}.
     */
    function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
        return _operatorApprovals[owner][operator];
    }

    /**
     * @dev See {IERC721-transferFrom}.
     */
    function transferFrom(address from, address to, uint256 tokenId) public virtual override {
        //solhint-disable-next-line max-line-length
        require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner or approved");

        _transfer(from, to, tokenId);
    }

    /**
     * @dev See {IERC721-safeTransferFrom}.
     */
    function safeTransferFrom(address from, address to, uint256 tokenId) public virtual override {
        safeTransferFrom(from, to, tokenId, "");
    }

    /**
     * @dev See {IERC721-safeTransferFrom}.
     */
    function safeTransferFrom(address from, address to, uint256 tokenId, bytes memory data) public virtual override {
        require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner or approved");
        _safeTransfer(from, to, tokenId, data);
    }

    /**
     * @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.
     *
     * `data` is additional data, it has no specified format and it is sent in call to `to`.
     *
     * This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.
     * implement alternative mechanisms to perform token transfer, such as signature-based.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function _safeTransfer(address from, address to, uint256 tokenId, bytes memory data) internal virtual {
        _transfer(from, to, tokenId);
        require(_checkOnERC721Received(from, to, tokenId, data), "ERC721: transfer to non ERC721Receiver implementer");
    }

    /**
     * @dev Returns the owner of the `tokenId`. Does NOT revert if token doesn't exist
     */
    function _ownerOf(uint256 tokenId) internal view virtual returns (address) {
        return _owners[tokenId];
    }

    /**
     * @dev Returns whether `tokenId` exists.
     *
     * Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
     *
     * Tokens start existing when they are minted (`_mint`),
     * and stop existing when they are burned (`_burn`).
     */
    function _exists(uint256 tokenId) internal view virtual returns (bool) {
        return _ownerOf(tokenId) != address(0);
    }

    /**
     * @dev Returns whether `spender` is allowed to manage `tokenId`.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function _isApprovedOrOwner(address spender, uint256 tokenId) internal view virtual returns (bool) {
        address owner = ERC721.ownerOf(tokenId);
        return (spender == owner || isApprovedForAll(owner, spender) || getApproved(tokenId) == spender);
    }

    /**
     * @dev Safely mints `tokenId` and transfers it to `to`.
     *
     * Requirements:
     *
     * - `tokenId` must not exist.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function _safeMint(address to, uint256 tokenId) internal virtual {
        _safeMint(to, tokenId, "");
    }

    /**
     * @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is
     * forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
     */
    function _safeMint(address to, uint256 tokenId, bytes memory data) internal virtual {
        _mint(to, tokenId);
        require(
            _checkOnERC721Received(address(0), to, tokenId, data),
            "ERC721: transfer to non ERC721Receiver implementer"
        );
    }

    /**
     * @dev Mints `tokenId` and transfers it to `to`.
     *
     * WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible
     *
     * Requirements:
     *
     * - `tokenId` must not exist.
     * - `to` cannot be the zero address.
     *
     * Emits a {Transfer} event.
     */
    function _mint(address to, uint256 tokenId) internal virtual {
        require(to != address(0), "ERC721: mint to the zero address");
        require(!_exists(tokenId), "ERC721: token already minted");

        _beforeTokenTransfer(address(0), to, tokenId, 1);

        // Check that tokenId was not minted by `_beforeTokenTransfer` hook
        require(!_exists(tokenId), "ERC721: token already minted");

        unchecked {
            // Will not overflow unless all 2**256 token ids are minted to the same owner.
            // Given that tokens are minted one by one, it is impossible in practice that
            // this ever happens. Might change if we allow batch minting.
            // The ERC fails to describe this case.
            _balances[to] += 1;
        }

        _owners[tokenId] = to;

        emit Transfer(address(0), to, tokenId);

        _afterTokenTransfer(address(0), to, tokenId, 1);
    }

    /**
     * @dev Destroys `tokenId`.
     * The approval is cleared when the token is burned.
     * This is an internal function that does not check if the sender is authorized to operate on the token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     *
     * Emits a {Transfer} event.
     */
    function _burn(uint256 tokenId) internal virtual {
        address owner = ERC721.ownerOf(tokenId);

        _beforeTokenTransfer(owner, address(0), tokenId, 1);

        // Update ownership in case tokenId was transferred by `_beforeTokenTransfer` hook
        owner = ERC721.ownerOf(tokenId);

        // Clear approvals
        delete _tokenApprovals[tokenId];

        unchecked {
            // Cannot overflow, as that would require more tokens to be burned/transferred
            // out than the owner initially received through minting and transferring in.
            _balances[owner] -= 1;
        }
        delete _owners[tokenId];

        emit Transfer(owner, address(0), tokenId);

        _afterTokenTransfer(owner, address(0), tokenId, 1);
    }

    /**
     * @dev Transfers `tokenId` from `from` to `to`.
     *  As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     *
     * Emits a {Transfer} event.
     */
    function _transfer(address from, address to, uint256 tokenId) internal virtual {
        require(ERC721.ownerOf(tokenId) == from, "ERC721: transfer from incorrect owner");
        require(to != address(0), "ERC721: transfer to the zero address");

        _beforeTokenTransfer(from, to, tokenId, 1);

        // Check that tokenId was not transferred by `_beforeTokenTransfer` hook
        require(ERC721.ownerOf(tokenId) == from, "ERC721: transfer from incorrect owner");

        // Clear approvals from the previous owner
        delete _tokenApprovals[tokenId];

        unchecked {
            // `_balances[from]` cannot overflow for the same reason as described in `_burn`:
            // `from`'s balance is the number of token held, which is at least one before the current
            // transfer.
            // `_balances[to]` could overflow in the conditions described in `_mint`. That would require
            // all 2**256 token ids to be minted, which in practice is impossible.
            _balances[from] -= 1;
            _balances[to] += 1;
        }
        _owners[tokenId] = to;

        emit Transfer(from, to, tokenId);

        _afterTokenTransfer(from, to, tokenId, 1);
    }

    /**
     * @dev Approve `to` to operate on `tokenId`
     *
     * Emits an {Approval} event.
     */
    function _approve(address to, uint256 tokenId) internal virtual {
        _tokenApprovals[tokenId] = to;
        emit Approval(ERC721.ownerOf(tokenId), to, tokenId);
    }

    /**
     * @dev Approve `operator` to operate on all of `owner` tokens
     *
     * Emits an {ApprovalForAll} event.
     */
    function _setApprovalForAll(address owner, address operator, bool approved) internal virtual {
        require(owner != operator, "ERC721: approve to caller");
        _operatorApprovals[owner][operator] = approved;
        emit ApprovalForAll(owner, operator, approved);
    }

    /**
     * @dev Reverts if the `tokenId` has not been minted yet.
     */
    function _requireMinted(uint256 tokenId) internal view virtual {
        require(_exists(tokenId), "ERC721: invalid token ID");
    }

    /**
     * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.
     * The call is not executed if the target address is not a contract.
     *
     * @param from address representing the previous owner of the given token ID
     * @param to target address that will receive the tokens
     * @param tokenId uint256 ID of the token to be transferred
     * @param data bytes optional data to send along with the call
     * @return bool whether the call correctly returned the expected magic value
     */
    function _checkOnERC721Received(
        address from,
        address to,
        uint256 tokenId,
        bytes memory data
    ) private returns (bool) {
        if (to.isContract()) {
            try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, data) returns (bytes4 retval) {
                return retval == IERC721Receiver.onERC721Received.selector;
            } catch (bytes memory reason) {
                if (reason.length == 0) {
                    revert("ERC721: transfer to non ERC721Receiver implementer");
                } else {
                    /// @solidity memory-safe-assembly
                    assembly {
                        revert(add(32, reason), mload(reason))
                    }
                }
            }
        } else {
            return true;
        }
    }

    /**
     * @dev Hook that is called before any token transfer. This includes minting and burning. If {ERC721Consecutive} is
     * used, the hook may be called as part of a consecutive (batch) mint, as indicated by `batchSize` greater than 1.
     *
     * Calling conditions:
     *
     * - When `from` and `to` are both non-zero, ``from``'s tokens will be transferred to `to`.
     * - When `from` is zero, the tokens will be minted for `to`.
     * - When `to` is zero, ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     * - `batchSize` is non-zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(address from, address to, uint256 firstTokenId, uint256 batchSize) internal virtual {}

    /**
     * @dev Hook that is called after any token transfer. This includes minting and burning. If {ERC721Consecutive} is
     * used, the hook may be called as part of a consecutive (batch) mint, as indicated by `batchSize` greater than 1.
     *
     * Calling conditions:
     *
     * - When `from` and `to` are both non-zero, ``from``'s tokens were transferred to `to`.
     * - When `from` is zero, the tokens were minted for `to`.
     * - When `to` is zero, ``from``'s tokens were burned.
     * - `from` and `to` are never both zero.
     * - `batchSize` is non-zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _afterTokenTransfer(address from, address to, uint256 firstTokenId, uint256 batchSize) internal virtual {}

    /**
     * @dev Unsafe write access to the balances, used by extensions that "mint" tokens using an {ownerOf} override.
     *
     * WARNING: Anyone calling this MUST ensure that the balances remain consistent with the ownership. The invariant
     * being that for any address `a` the value returned by `balanceOf(a)` must be equal to the number of tokens such
     * that `ownerOf(tokenId)` is `a`.
     */
    // solhint-disable-next-line func-name-mixedcase
    function __unsafe_increaseBalance(address account, uint256 amount) internal {
        _balances[account] += amount;
    }
}


balance

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/IERC721Metadata.sol)

pragma solidity ^0.8.0;

import "../IERC721.sol";

/**
 * @title ERC-721 Non-Fungible Token Standard, optional metadata extension
 * @dev See https://eips.ethereum.org/EIPS/eip-721
 */
interface IERC721Metadata is IERC721 {
    /**
     * @dev Returns the token collection name.
     */
    function name() external view returns (string memory);

    /**
     * @dev Returns the token collection symbol.
     */
    function symbol() external view returns (string memory);

    /**
     * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
     */
    function tokenURI(uint256 tokenId) external view returns (string memory);
}


ERC-721 Non-Fungible Token Standard, optional metadata extension

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (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);
}


onERC721Received

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC721/IERC721Receiver.sol)

pragma solidity ^0.8.0;

/**
 * @title ERC721 token receiver interface
 * @dev Interface for any contract that wants to support safeTransfers
 * from ERC721 asset contracts.
 */
interface IERC721Receiver {
    /**
     * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
     * by `operator` from `from`, this function is called.
     *
     * It must return its Solidity selector to confirm the token transfer.
     * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
     *
     * The selector can be obtained in Solidity with `IERC721Receiver.onERC721Received.selector`.
     */
    function onERC721Received(
        address operator,
        address from,
        uint256 tokenId,
        bytes calldata data
    ) external returns (bytes4);
}


ERC721 token receiver interface

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol)

pragma solidity ^0.8.1;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @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
     *
     * Furthermore, `isContract` will also return true if the target contract within
     * the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
     * which only has an effect at the end of a transaction.
     * ====
     *
     * [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://consensys.net/diligence/blog/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/v0.8.0/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 Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        (bool success, bytes memory returndata) = target.delegatecall(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);
        }
    }
}


// SPDX-License-Identifier: MIT
// 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;
    }
}


// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/cryptography/ECDSA.sol)

pragma solidity ^0.8.0;

import "../Strings.sol";

/**
 * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
 *
 * These functions can be used to verify that a message was signed by the holder
 * of the private keys of a given address.
 */
library ECDSA {
    enum RecoverError {
        NoError,
        InvalidSignature,
        InvalidSignatureLength,
        InvalidSignatureS,
        InvalidSignatureV // Deprecated in v4.8
    }

    function _throwError(RecoverError error) private pure {
        if (error == RecoverError.NoError) {
            return; // no error: do nothing
        } else if (error == RecoverError.InvalidSignature) {
            revert("ECDSA: invalid signature");
        } else if (error == RecoverError.InvalidSignatureLength) {
            revert("ECDSA: invalid signature length");
        } else if (error == RecoverError.InvalidSignatureS) {
            revert("ECDSA: invalid signature 's' value");
        }
    }

    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature` or error string. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
     * this function rejects them by requiring the `s` value to be in the lower
     * half order, and the `v` value to be either 27 or 28.
     *
     * IMPORTANT: `hash` _must_ be the result of a hash operation for the
     * verification to be secure: it is possible to craft signatures that
     * recover to arbitrary addresses for non-hashed data. A safe way to ensure
     * this is by receiving a hash of the original message (which may otherwise
     * be too long), and then calling {toEthSignedMessageHash} on it.
     *
     * Documentation for signature generation:
     * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
     * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
     *
     * _Available since v4.3._
     */
    function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
        if (signature.length == 65) {
            bytes32 r;
            bytes32 s;
            uint8 v;
            // ecrecover takes the signature parameters, and the only way to get them
            // currently is to use assembly.
            /// @solidity memory-safe-assembly
            assembly {
                r := mload(add(signature, 0x20))
                s := mload(add(signature, 0x40))
                v := byte(0, mload(add(signature, 0x60)))
            }
            return tryRecover(hash, v, r, s);
        } else {
            return (address(0), RecoverError.InvalidSignatureLength);
        }
    }

    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature`. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
     * this function rejects them by requiring the `s` value to be in the lower
     * half order, and the `v` value to be either 27 or 28.
     *
     * IMPORTANT: `hash` _must_ be the result of a hash operation for the
     * verification to be secure: it is possible to craft signatures that
     * recover to arbitrary addresses for non-hashed data. A safe way to ensure
     * this is by receiving a hash of the original message (which may otherwise
     * be too long), and then calling {toEthSignedMessageHash} on it.
     */
    function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, signature);
        _throwError(error);
        return recovered;
    }

    /**
     * @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
     *
     * See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
     *
     * _Available since v4.3._
     */
    function tryRecover(bytes32 hash, bytes32 r, bytes32 vs) internal pure returns (address, RecoverError) {
        bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
        uint8 v = uint8((uint256(vs) >> 255) + 27);
        return tryRecover(hash, v, r, s);
    }

    /**
     * @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
     *
     * _Available since v4.2._
     */
    function recover(bytes32 hash, bytes32 r, bytes32 vs) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, r, vs);
        _throwError(error);
        return recovered;
    }

    /**
     * @dev Overload of {ECDSA-tryRecover} that receives the `v`,
     * `r` and `s` signature fields separately.
     *
     * _Available since v4.3._
     */
    function tryRecover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal pure returns (address, RecoverError) {
        // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
        // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
        // the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
        // signatures from current libraries generate a unique signature with an s-value in the lower half order.
        //
        // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
        // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
        // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
        // these malleable signatures as well.
        if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
            return (address(0), RecoverError.InvalidSignatureS);
        }

        // If the signature is valid (and not malleable), return the signer address
        address signer = ecrecover(hash, v, r, s);
        if (signer == address(0)) {
            return (address(0), RecoverError.InvalidSignature);
        }

        return (signer, RecoverError.NoError);
    }

    /**
     * @dev Overload of {ECDSA-recover} that receives the `v`,
     * `r` and `s` signature fields separately.
     */
    function recover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, v, r, s);
        _throwError(error);
        return recovered;
    }

    /**
     * @dev Returns an Ethereum Signed Message, created from a `hash`. This
     * produces hash corresponding to the one signed with the
     * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
     * JSON-RPC method as part of EIP-191.
     *
     * See {recover}.
     */
    function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32 message) {
        // 32 is the length in bytes of hash,
        // enforced by the type signature above
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, "\x19Ethereum Signed Message:\n32")
            mstore(0x1c, hash)
            message := keccak256(0x00, 0x3c)
        }
    }

    /**
     * @dev Returns an Ethereum Signed Message, created from `s`. This
     * produces hash corresponding to the one signed with the
     * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
     * JSON-RPC method as part of EIP-191.
     *
     * See {recover}.
     */
    function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n", Strings.toString(s.length), s));
    }

    /**
     * @dev Returns an Ethereum Signed Typed Data, created from a
     * `domainSeparator` and a `structHash`. This produces hash corresponding
     * to the one signed with the
     * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
     * JSON-RPC method as part of EIP-712.
     *
     * See {recover}.
     */
    function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32 data) {
        /// @solidity memory-safe-assembly
        assembly {
            let ptr := mload(0x40)
            mstore(ptr, "\x19\x01")
            mstore(add(ptr, 0x02), domainSeparator)
            mstore(add(ptr, 0x22), structHash)
            data := keccak256(ptr, 0x42)
        }
    }

    /**
     * @dev Returns an Ethereum Signed Data with intended validator, created from a
     * `validator` and `data` according to the version 0 of EIP-191.
     *
     * See {recover}.
     */
    function toDataWithIntendedValidatorHash(address validator, bytes memory data) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked("\x19\x00", validator, data));
    }
}


// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)

pragma solidity ^0.8.0;

import "./IERC165.sol";

/**
 * @dev Implementation of the {IERC165} interface.
 *
 * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
 * for the additional interface id that will be supported. For example:
 *
 * ```solidity
 * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
 *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
 * }
 * ```
 *
 * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
 */
abstract contract ERC165 is IERC165 {
    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
        return interfaceId == type(IERC165).interfaceId;
    }
}


// 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);
}


// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/math/Math.sol)

pragma solidity ^0.8.0;

/**
 * @dev Standard math utilities missing in the Solidity language.
 */
library Math {
    enum Rounding {
        Down, // Toward negative infinity
        Up, // Toward infinity
        Zero // Toward zero
    }

    /**
     * @dev Returns the largest of two numbers.
     */
    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a > b ? a : b;
    }

    /**
     * @dev Returns the smallest of two numbers.
     */
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }

    /**
     * @dev Returns the average of two numbers. The result is rounded towards
     * zero.
     */
    function average(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b) / 2 can overflow.
        return (a & b) + (a ^ b) / 2;
    }

    /**
     * @dev Returns the ceiling of the division of two numbers.
     *
     * This differs from standard division with `/` in that it rounds up instead
     * of rounding down.
     */
    function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b - 1) / b can overflow on addition, so we distribute.
        return a == 0 ? 0 : (a - 1) / b + 1;
    }

    /**
     * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
     * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
     * with further edits by Uniswap Labs also under MIT license.
     */
    function mulDiv(uint256 x, uint256 y, uint256 denominator) internal pure returns (uint256 result) {
        unchecked {
            // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
            // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
            // variables such that product = prod1 * 2^256 + prod0.
            uint256 prod0; // Least significant 256 bits of the product
            uint256 prod1; // Most significant 256 bits of the product
            assembly {
                let mm := mulmod(x, y, not(0))
                prod0 := mul(x, y)
                prod1 := sub(sub(mm, prod0), lt(mm, prod0))
            }

            // Handle non-overflow cases, 256 by 256 division.
            if (prod1 == 0) {
                // Solidity will revert if denominator == 0, unlike the div opcode on its own.
                // The surrounding unchecked block does not change this fact.
                // See https://docs.soliditylang.org/en/latest/control-structures.html#checked-or-unchecked-arithmetic.
                return prod0 / denominator;
            }

            // Make sure the result is less than 2^256. Also prevents denominator == 0.
            require(denominator > prod1, "Math: mulDiv overflow");

            ///////////////////////////////////////////////
            // 512 by 256 division.
            ///////////////////////////////////////////////

            // Make division exact by subtracting the remainder from [prod1 prod0].
            uint256 remainder;
            assembly {
                // Compute remainder using mulmod.
                remainder := mulmod(x, y, denominator)

                // Subtract 256 bit number from 512 bit number.
                prod1 := sub(prod1, gt(remainder, prod0))
                prod0 := sub(prod0, remainder)
            }

            // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
            // See https://cs.stackexchange.com/q/138556/92363.

            // Does not overflow because the denominator cannot be zero at this stage in the function.
            uint256 twos = denominator & (~denominator + 1);
            assembly {
                // Divide denominator by twos.
                denominator := div(denominator, twos)

                // Divide [prod1 prod0] by twos.
                prod0 := div(prod0, twos)

                // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                twos := add(div(sub(0, twos), twos), 1)
            }

            // Shift in bits from prod1 into prod0.
            prod0 |= prod1 * twos;

            // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
            // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
            // four bits. That is, denominator * inv = 1 mod 2^4.
            uint256 inverse = (3 * denominator) ^ 2;

            // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
            // in modular arithmetic, doubling the correct bits in each step.
            inverse *= 2 - denominator * inverse; // inverse mod 2^8
            inverse *= 2 - denominator * inverse; // inverse mod 2^16
            inverse *= 2 - denominator * inverse; // inverse mod 2^32
            inverse *= 2 - denominator * inverse; // inverse mod 2^64
            inverse *= 2 - denominator * inverse; // inverse mod 2^128
            inverse *= 2 - denominator * inverse; // inverse mod 2^256

            // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
            // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
            // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
            // is no longer required.
            result = prod0 * inverse;
            return result;
        }
    }

    /**
     * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
     */
    function mulDiv(uint256 x, uint256 y, uint256 denominator, Rounding rounding) internal pure returns (uint256) {
        uint256 result = mulDiv(x, y, denominator);
        if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
            result += 1;
        }
        return result;
    }

    /**
     * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
     *
     * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
     */
    function sqrt(uint256 a) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }

        // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
        //
        // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
        // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
        //
        // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
        // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
        // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
        //
        // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
        uint256 result = 1 << (log2(a) >> 1);

        // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
        // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
        // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
        // into the expected uint128 result.
        unchecked {
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            return min(result, a / result);
        }
    }

    /**
     * @notice Calculates sqrt(a), following the selected rounding direction.
     */
    function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = sqrt(a);
            return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 2, rounded down, of a positive value.
     * Returns 0 if given 0.
     */
    function log2(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 128;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 64;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 32;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 16;
            }
            if (value >> 8 > 0) {
                value >>= 8;
                result += 8;
            }
            if (value >> 4 > 0) {
                value >>= 4;
                result += 4;
            }
            if (value >> 2 > 0) {
                value >>= 2;
                result += 2;
            }
            if (value >> 1 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 2, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log2(value);
            return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 10, rounded down, of a positive value.
     * Returns 0 if given 0.
     */
    function log10(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >= 10 ** 64) {
                value /= 10 ** 64;
                result += 64;
            }
            if (value >= 10 ** 32) {
                value /= 10 ** 32;
                result += 32;
            }
            if (value >= 10 ** 16) {
                value /= 10 ** 16;
                result += 16;
            }
            if (value >= 10 ** 8) {
                value /= 10 ** 8;
                result += 8;
            }
            if (value >= 10 ** 4) {
                value /= 10 ** 4;
                result += 4;
            }
            if (value >= 10 ** 2) {
                value /= 10 ** 2;
                result += 2;
            }
            if (value >= 10 ** 1) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log10(value);
            return result + (rounding == Rounding.Up && 10 ** result < value ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 256, rounded down, of a positive value.
     * Returns 0 if given 0.
     *
     * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
     */
    function log256(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 16;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 8;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 4;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 2;
            }
            if (value >> 8 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 256, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log256(value);
            return result + (rounding == Rounding.Up && 1 << (result << 3) < value ? 1 : 0);
        }
    }
}


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

pragma solidity ^0.8.0;

/**
 * @dev Standard signed math utilities missing in the Solidity language.
 */
library SignedMath {
    /**
     * @dev Returns the largest of two signed numbers.
     */
    function max(int256 a, int256 b) internal pure returns (int256) {
        return a > b ? a : b;
    }

    /**
     * @dev Returns the smallest of two signed numbers.
     */
    function min(int256 a, int256 b) internal pure returns (int256) {
        return a < b ? a : b;
    }

    /**
     * @dev Returns the average of two signed numbers without overflow.
     * The result is rounded towards zero.
     */
    function average(int256 a, int256 b) internal pure returns (int256) {
        // Formula from the book "Hacker's Delight"
        int256 x = (a & b) + ((a ^ b) >> 1);
        return x + (int256(uint256(x) >> 255) & (a ^ b));
    }

    /**
     * @dev Returns the absolute unsigned value of a signed value.
     */
    function abs(int256 n) internal pure returns (uint256) {
        unchecked {
            // must be unchecked in order to support `n = type(int256).min`
            return uint256(n >= 0 ? n : -n);
        }
    }
}


// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/Strings.sol)

pragma solidity ^0.8.0;

import "./math/Math.sol";
import "./math/SignedMath.sol";

/**
 * @dev String operations.
 */
library Strings {
    bytes16 private constant _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) {
        unchecked {
            uint256 length = Math.log10(value) + 1;
            string memory buffer = new string(length);
            uint256 ptr;
            /// @solidity memory-safe-assembly
            assembly {
                ptr := add(buffer, add(32, length))
            }
            while (true) {
                ptr--;
                /// @solidity memory-safe-assembly
                assembly {
                    mstore8(ptr, byte(mod(value, 10), _SYMBOLS))
                }
                value /= 10;
                if (value == 0) break;
            }
            return buffer;
        }
    }

    /**
     * @dev Converts a `int256` to its ASCII `string` decimal representation.
     */
    function toString(int256 value) internal pure returns (string memory) {
        return string(abi.encodePacked(value < 0 ? "-" : "", toString(SignedMath.abs(value))));
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        unchecked {
            return toHexString(value, Math.log256(value) + 1);
        }
    }

    /**
     * @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] = _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);
    }

    /**
     * @dev Returns true if the two strings are equal.
     */
    function equal(string memory a, string memory b) internal pure returns (bool) {
        return keccak256(bytes(a)) == keccak256(bytes(b));
    }
}


OnlyPortalOwner

attestationPayload

validationPayload

txSender

value

interfaceID

// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;

import { AttestationPayload } from "../types/Structs.sol";
import { IERC165 } from "openzeppelin-contracts/contracts/utils/introspection/IERC165.sol";

/**
 * @title Abstract Module
 * @author Consensys
 * @notice Defines the minimal Module interface
 */
abstract contract AbstractModule is IERC165 {
  /// @notice Error thrown when someone else than the portal's owner is trying to revoke
  error OnlyPortalOwner();

  /**
   * @notice Executes the module's custom logic.
   * @param attestationPayload The incoming attestation data.
   * @param validationPayload Additional data required for verification.
   * @param txSender The transaction sender's address.
   * @param value The transaction value.
   */
  function run(
    AttestationPayload memory attestationPayload,
    bytes memory validationPayload,
    address txSender,
    uint256 value
  ) public virtual;

  /**
   * @notice Checks if the contract implements the Module interface.
   * @param interfaceID The ID of the interface to check.
   * @return A boolean indicating interface support.
   */
  function supportsInterface(bytes4 interfaceID) public pure virtual override returns (bool) {
    return interfaceID == type(AbstractModule).interfaceId || interfaceID == type(IERC165).interfaceId;
  }
}


Abstract Module

validationPayloads

attest

attestationRegistry

attestationsPayloads

bulkAttest

attestationIds

bulkReplace

bulkRevoke

getAttester

getModules

moduleRegistry

modules

portalRegistry

attestationId

replace

revoke

router

amount

withdraw

// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;

import { AttestationRegistry } from "../AttestationRegistry.sol";
import { ModuleRegistry } from "../ModuleRegistry.sol";
import { PortalRegistry } from "../PortalRegistry.sol";
import { AttestationPayload } from "../types/Structs.sol";
import { IERC165 } from "openzeppelin-contracts/contracts/utils/introspection/ERC165.sol";
import { IRouter } from "../interfaces/IRouter.sol";
import { IPortal } from "../interfaces/IPortal.sol";

/**
 * @title Abstract Portal
 * @author Consensys
 * @notice This contract is an abstract contract with basic Portal logic
 *         to be inherited. We strongly encourage all Portals to implement
 *         this contract.
 */
abstract contract AbstractPortal is IPortal {
  IRouter public router;
  address[] public modules;
  ModuleRegistry public moduleRegistry;
  AttestationRegistry public attestationRegistry;
  PortalRegistry public portalRegistry;

  /// @notice Error thrown when someone else than the portal's owner is trying to revoke
  error OnlyPortalOwner();

  /**
   * @notice Contract constructor
   * @param _modules list of modules to use for the portal (can be empty)
   * @param _router Router's address
   * @dev This sets the addresses for the AttestationRegistry, ModuleRegistry and PortalRegistry
   */
  constructor(address[] memory _modules, address _router) {
    modules = _modules;
    router = IRouter(_router);
    attestationRegistry = AttestationRegistry(router.getAttestationRegistry());
    moduleRegistry = ModuleRegistry(router.getModuleRegistry());
    portalRegistry = PortalRegistry(router.getPortalRegistry());
  }

  /**
   * @notice Optional method to withdraw funds from the Portal
   * @param to the address to send the funds to
   * @param amount the amount to withdraw
   */
  function withdraw(address payable to, uint256 amount) external virtual;

  /**
   * @notice Attest the schema with given attestationPayload and validationPayload
   * @param attestationPayload the payload to attest
   * @param validationPayloads the payloads to validate via the modules to issue the attestations
   * @dev Runs all modules for the portal and registers the attestation using AttestationRegistry
   */
  function attest(AttestationPayload memory attestationPayload, bytes[] memory validationPayloads) public payable {
    moduleRegistry.runModules(modules, attestationPayload, validationPayloads, msg.value);

    _onAttest(attestationPayload, getAttester(), msg.value);

    attestationRegistry.attest(attestationPayload, getAttester());
  }

  /**
   * @notice Bulk attest the schema with payloads to attest and validation payloads
   * @param attestationsPayloads the payloads to attest
   * @param validationPayloads the payloads to validate via the modules to issue the attestations
   */
  function bulkAttest(AttestationPayload[] memory attestationsPayloads, bytes[][] memory validationPayloads) public {
    moduleRegistry.bulkRunModules(modules, attestationsPayloads, validationPayloads);

    _onBulkAttest(attestationsPayloads, validationPayloads);

    attestationRegistry.bulkAttest(attestationsPayloads, getAttester());
  }

  /**
   * @notice Replaces the attestation for the given identifier and replaces it with a new attestation
   * @param attestationId the ID of the attestation to replace
   * @param attestationPayload the attestation payload to create the new attestation and register it
   * @param validationPayloads the payloads to validate via the modules to issue the attestation
   * @dev Runs all modules for the portal and registers the attestation using AttestationRegistry
   */
  function replace(
    bytes32 attestationId,
    AttestationPayload memory attestationPayload,
    bytes[] memory validationPayloads
  ) public payable {
    moduleRegistry.runModules(modules, attestationPayload, validationPayloads, msg.value);

    _onReplace(attestationId, attestationPayload, getAttester(), msg.value);

    attestationRegistry.replace(attestationId, attestationPayload, getAttester());
  }

  /**
   * @notice Bulk replaces the attestation for the given identifiers and replaces them with new attestations
   * @param attestationIds the list of IDs of the attestations to replace
   * @param attestationsPayloads the list of attestation payloads to create the new attestations and register them
   * @param validationPayloads the payloads to validate via the modules to issue the attestations
   */
  function bulkReplace(
    bytes32[] memory attestationIds,
    AttestationPayload[] memory attestationsPayloads,
    bytes[][] memory validationPayloads
  ) public {
    moduleRegistry.bulkRunModules(modules, attestationsPayloads, validationPayloads);

    _onBulkReplace(attestationIds, attestationsPayloads, validationPayloads);

    attestationRegistry.bulkReplace(attestationIds, attestationsPayloads, getAttester());
  }

  /**
   * @notice Revokes an attestation for the given identifier
   * @param attestationId the ID of the attestation to revoke
   * @dev By default, revocation is only possible by the portal owner
   * We strongly encourage implementing such a rule in your Portal if you intend on overriding this method
   */
  function revoke(bytes32 attestationId) public {
    _onRevoke(attestationId);

    attestationRegistry.revoke(attestationId);
  }

  /**
   * @notice Bulk revokes a list of attestations for the given identifiers
   * @param attestationIds the IDs of the attestations to revoke
   */
  function bulkRevoke(bytes32[] memory attestationIds) public {
    _onBulkRevoke(attestationIds);

    attestationRegistry.bulkRevoke(attestationIds);
  }

  /**
   * @notice Get all the modules addresses used by the Portal
   * @return The list of modules addresses linked to the Portal
   */
  function getModules() external view returns (address[] memory) {
    return modules;
  }

  /**
   * @notice Verifies that a specific interface is implemented by the Portal, following ERC-165 specification
   * @param interfaceID the interface identifier checked in this call
   * @return The list of modules addresses linked to the Portal
   */
  function supportsInterface(bytes4 interfaceID) public pure virtual override returns (bool) {
    return
      interfaceID == type(AbstractPortal).interfaceId ||
      interfaceID == type(IPortal).interfaceId ||
      interfaceID == type(IERC165).interfaceId;
  }

  /**
   * @notice Defines the address of the entity issuing attestations to the subject
   * @dev We strongly encourage a reflection when overriding this rule: who should be set as the attester?
   */
  function getAttester() public view virtual returns (address) {
    return msg.sender;
  }

  /**
   * @notice Optional method run before a payload is attested
   * @param attestationPayload the attestation payload supposed to be attested
   * @param attester the address of the attester
   * @param value the value sent with the attestation
   */
  function _onAttest(AttestationPayload memory attestationPayload, address attester, uint256 value) internal virtual {}

  /**
   * @notice Optional method run when an attestation is replaced
   * @param attestationId the ID of the attestation being replaced
   * @param attestationPayload the attestation payload to create attestation and register it
   * @param attester the address of the attester
   * @param value the value sent with the attestation
   */
  function _onReplace(
    bytes32 attestationId,
    AttestationPayload memory attestationPayload,
    address attester,
    uint256 value
  ) internal virtual {}

  /**
   * @notice Optional method run when attesting a batch of payloads
   * @param attestationsPayloads the payloads to attest
   * @param validationPayloads the payloads to validate in order to issue the attestations
   */
  function _onBulkAttest(
    AttestationPayload[] memory attestationsPayloads,
    bytes[][] memory validationPayloads
  ) internal virtual {}

  function _onBulkReplace(
    bytes32[] memory attestationIds,
    AttestationPayload[] memory attestationsPayloads,
    bytes[][] memory validationPayloads
  ) internal virtual {}

  /**
   * @notice Optional method run when an attestation is revoked or replaced
   * @dev    IMPORTANT NOTE: By default, revocation is only possible by the portal owner
   */
  function _onRevoke(bytes32 /*attestationId*/) internal virtual {
    if (msg.sender != portalRegistry.getPortalByAddress(address(this)).ownerAddress) revert OnlyPortalOwner();
  }

  /**
   * @notice Optional method run when a batch of attestations are revoked or replaced
   * @dev    IMPORTANT NOTE: By default, revocation is only possible by the portal owner
   */
  function _onBulkRevoke(bytes32[] memory /*attestationIds*/) internal virtual {
    if (msg.sender != portalRegistry.getPortalByAddress(address(this)).ownerAddress) revert OnlyPortalOwner();
  }
}


Abstract Portal

EASAddressInvalid

RouterInvalid

easRegistry

getAttestation

attestation

initialize

_easRegistryAddress

updateEASRegistryAddress

_router

updateRouter

// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;

import { OwnableUpgradeable } from "openzeppelin-contracts-upgradeable/contracts/access/OwnableUpgradeable.sol";
import { Attestation as EASAttestation, IEAS } from "./interfaces/IEAS.sol";
import { Attestation } from "./types/Structs.sol";
import { AttestationRegistry } from "./AttestationRegistry.sol";
import { PortalRegistry } from "./PortalRegistry.sol";
import { IRouter } from "./interfaces/IRouter.sol";

/**
 * @title Attestation Reader
 * @author Consensys
 * @notice This contract allows to read attestations stored by EAS or Verax
 */
contract AttestationReader is OwnableUpgradeable {
  IRouter public router;
  IEAS public easRegistry;

  /// @notice Error thrown when an invalid Router address is given
  error RouterInvalid();
  /// @notice Error thrown when an invalid EAS registry address is given
  error EASAddressInvalid();

  /**
   * @notice Contract initialization
   */
  function initialize() public initializer {
    __Ownable_init();
  }

  /// @custom:oz-upgrades-unsafe-allow constructor
  constructor() {
    _disableInitializers();
  }

  /**
   * @notice Changes the address for the Router
   * @dev Only the registry owner can call this method
   */
  function updateRouter(address _router) public onlyOwner {
    if (_router == address(0)) revert RouterInvalid();
    router = IRouter(_router);
  }

  /**
   * @notice Changes the address for the EAS attestation registry
   * @param _easRegistryAddress the new EAS Registry address
   * @dev Only the owner can call this method
   */
  function updateEASRegistryAddress(address _easRegistryAddress) public onlyOwner {
    if (_easRegistryAddress == address(0)) revert EASAddressInvalid();
    easRegistry = IEAS(_easRegistryAddress);
  }

  /**
   * @notice Gets an attestation by its identifier
   * @param uid the attestation identifier
   * @return attestation the attestation, following EAS's format
   */
  function getAttestation(bytes32 uid) public view returns (EASAttestation memory attestation) {
    attestation = easRegistry.getAttestation(uid);
    if (attestation.schema == bytes32(0)) {
      AttestationRegistry veraxAttestationRegistry = AttestationRegistry(router.getAttestationRegistry());
      Attestation memory veraxAttestation = veraxAttestationRegistry.getAttestation(uid);
      attestation = _convertToEASAttestation(veraxAttestation);
    }
  }

  /**
   * @notice Converts a Verax attestation to an EAS attestation
   * @param veraxAttestation the Verax attestation to convert
   * @return The EAS attestation converted from the Verax attestation
   * @dev The EAS attestation will have a "zero address" subject if the original subject is not an address
   */
  function _convertToEASAttestation(Attestation memory veraxAttestation) private view returns (EASAttestation memory) {
    address subject = address(0);

    if (veraxAttestation.subject.length == 32) subject = abi.decode(veraxAttestation.subject, (address));
    if (veraxAttestation.subject.length == 20) subject = address(uint160(bytes20(veraxAttestation.subject)));

    return
      EASAttestation(
        veraxAttestation.attestationId,
        veraxAttestation.schemaId,
        veraxAttestation.attestedDate,
        veraxAttestation.expirationDate,
        veraxAttestation.revocationDate,
        bytes32(0),
        subject,
        veraxAttestation.attester,
        PortalRegistry(router.getPortalRegistry()).getPortalByAddress(veraxAttestation.portal).isRevocable,
        veraxAttestation.attestationData
      );
  }
}


The AttestationReader contract retrieves attestations from the EAS or Verax systems, allowing updates to router and EAS registry addresses by the owner. It provides a function to convert Verax attestations to EAS format and fetches attestations by ID, handling conversion if necessary.

Attestation Reader

AlreadyRevoked

ArrayLengthMismatch

AttestationDataFieldEmpty

AttestationNotAttested

AttestationNotRevocable

AttestationSubjectFieldEmpty

OnlyAttestingPortal

OnlyPortal

SchemaNotRegistered

AttestationRegistered

replacedBy

AttestationReplaced

AttestationRevoked

VersionUpdated

attester

account

accounts

balanceOfBatch

attestationPayloads

getAttestationIdCounter

getChainPrefix

getVersionNumber

incrementVersionNumber

isRegistered

portalId

isRevocable

portal

massImport

_chainPrefix

updateChainPrefix

// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;

import { OwnableUpgradeable } from "openzeppelin-contracts-upgradeable/contracts/access/OwnableUpgradeable.sol";
import { Attestation, AttestationPayload } from "./types/Structs.sol";
import { PortalRegistry } from "./PortalRegistry.sol";
import { SchemaRegistry } from "./SchemaRegistry.sol";
import { IRouter } from "./interfaces/IRouter.sol";
import { uncheckedInc256 } from "./Common.sol";

/**
 * @title Attestation Registry
 * @author Consensys
 * @notice This contract stores a registry of all attestations
 */
contract AttestationRegistry is OwnableUpgradeable {
  IRouter public router;

  uint16 private version;
  uint32 private attestationIdCounter;

  mapping(bytes32 attestationId => Attestation attestation) private attestations;

  uint256 private chainPrefix;

  /// @notice Error thrown when a non-portal tries to call a method that can only be called by a portal
  error OnlyPortal();
  /// @notice Error thrown when an invalid Router address is given
  error RouterInvalid();
  /// @notice Error thrown when an attestation is not registered in the AttestationRegistry
  error AttestationNotAttested();
  /// @notice Error thrown when an attempt is made to revoke an attestation by an entity other than the attesting portal
  error OnlyAttestingPortal();
  /// @notice Error thrown when a schema id is not registered
  error SchemaNotRegistered();
  /// @notice Error thrown when an attestation subject is empty
  error AttestationSubjectFieldEmpty();
  /// @notice Error thrown when an attestation data field is empty
  error AttestationDataFieldEmpty();
  /// @notice Error thrown when an attempt is made to bulk replace with mismatched parameter array lengths
  error ArrayLengthMismatch();
  /// @notice Error thrown when an attempt is made to revoke an attestation that was already revoked
  error AlreadyRevoked();
  /// @notice Error thrown when an attempt is made to revoke an attestation based on a non-revocable schema
  error AttestationNotRevocable();

  /// @notice Event emitted when an attestation is registered
  event AttestationRegistered(bytes32 indexed attestationId);
  /// @notice Event emitted when an attestation is replaced
  event AttestationReplaced(bytes32 attestationId, bytes32 replacedBy);
  /// @notice Event emitted when an attestation is revoked
  event AttestationRevoked(bytes32 attestationId);
  /// @notice Event emitted when the version number is incremented
  event VersionUpdated(uint16 version);

  /**
   * @notice Checks if the caller is a registered portal
   * @param portal the portal address
   */
  modifier onlyPortals(address portal) {
    bool isPortalRegistered = PortalRegistry(router.getPortalRegistry()).isRegistered(portal);
    if (!isPortalRegistered) revert OnlyPortal();
    _;
  }

  /// @custom:oz-upgrades-unsafe-allow constructor
  constructor() {
    _disableInitializers();
  }

  /**
   * @notice Contract initialization
   */
  function initialize() public initializer {
    __Ownable_init();
  }

  /**
   * @notice Changes the address for the Router
   * @dev Only the registry owner can call this method
   */
  function updateRouter(address _router) public onlyOwner {
    if (_router == address(0)) revert RouterInvalid();
    router = IRouter(_router);
  }

  /**
   * @notice Changes the chain prefix for the attestation IDs
   * @dev Only the registry owner can call this method
   */
  function updateChainPrefix(uint256 _chainPrefix) public onlyOwner {
    chainPrefix = _chainPrefix;
  }

  /**
   * @notice Registers an attestation to the AttestationRegistry
   * @param attestationPayload the attestation payload to create attestation and register it
   * @param attester the account address issuing the attestation
   * @dev This method is only callable by a registered Portal
   */
  function attest(AttestationPayload calldata attestationPayload, address attester) public onlyPortals(msg.sender) {
    // Verify the schema id exists
    SchemaRegistry schemaRegistry = SchemaRegistry(router.getSchemaRegistry());
    if (!schemaRegistry.isRegistered(attestationPayload.schemaId)) revert SchemaNotRegistered();
    // Verify the subject field is not blank
    if (attestationPayload.subject.length == 0) revert AttestationSubjectFieldEmpty();
    // Verify the attestationData field is not blank
    if (attestationPayload.attestationData.length == 0) revert AttestationDataFieldEmpty();
    // Auto increment attestation counter
    attestationIdCounter++;
    // Generate the full attestation ID, padded with the chain prefix
    bytes32 id = generateAttestationId(attestationIdCounter);
    // Create attestation
    attestations[id] = Attestation(
      id,
      attestationPayload.schemaId,
      bytes32(0),
      attester,
      msg.sender,
      uint64(block.timestamp),
      attestationPayload.expirationDate,
      0,
      version,
      false,
      attestationPayload.subject,
      attestationPayload.attestationData
    );
    emit AttestationRegistered(id);
  }

  /**
   * @notice Registers attestations to the AttestationRegistry
   * @param attestationsPayloads the attestations payloads to create attestations and register them
   */
  function bulkAttest(AttestationPayload[] calldata attestationsPayloads, address attester) public {
    for (uint256 i = 0; i < attestationsPayloads.length; i = uncheckedInc256(i)) {
      attest(attestationsPayloads[i], attester);
    }
  }

  function massImport(AttestationPayload[] calldata attestationsPayloads, address portal) public onlyOwner {
    for (uint256 i = 0; i < attestationsPayloads.length; i = uncheckedInc256(i)) {
      // Auto increment attestation counter
      attestationIdCounter++;
      // Generate the full attestation ID, padded with the chain prefix
      bytes32 id = generateAttestationId(attestationIdCounter);
      // Create attestation
      attestations[id] = Attestation(
        id,
        attestationsPayloads[i].schemaId,
        bytes32(0),
        msg.sender,
        portal,
        uint64(block.timestamp),
        attestationsPayloads[i].expirationDate,
        0,
        version,
        false,
        attestationsPayloads[i].subject,
        attestationsPayloads[i].attestationData
      );
      emit AttestationRegistered(id);
    }
  }

  /**
   * @notice Replaces an attestation for the given identifier and replaces it with a new attestation
   * @param attestationId the ID of the attestation to replace
   * @param attestationPayload the attestation payload to create the new attestation and register it
   * @param attester the account address issuing the attestation
   */
  function replace(bytes32 attestationId, AttestationPayload calldata attestationPayload, address attester) public {
    attest(attestationPayload, attester);
    revoke(attestationId);
    bytes32 replacedBy = generateAttestationId(attestationIdCounter);
    attestations[attestationId].replacedBy = replacedBy;

    emit AttestationReplaced(attestationId, replacedBy);
  }

  /**
   * @notice Replaces attestations for given identifiers and replaces them with new attestations
   * @param attestationIds the list of IDs of the attestations to replace
   * @param attestationPayloads the list of attestation payloads to create the new attestations and register them
   * @param attester the account address issuing the attestation
   */
  function bulkReplace(
    bytes32[] calldata attestationIds,
    AttestationPayload[] calldata attestationPayloads,
    address attester
  ) public {
    if (attestationIds.length != attestationPayloads.length) revert ArrayLengthMismatch();
    for (uint256 i = 0; i < attestationIds.length; i = uncheckedInc256(i)) {
      replace(attestationIds[i], attestationPayloads[i], attester);
    }
  }

  /**
   * @notice Revokes an attestation for a given identifier
   * @param attestationId the ID of the attestation to revoke
   */
  function revoke(bytes32 attestationId) public {
    if (!isRegistered(attestationId)) revert AttestationNotAttested();
    if (attestations[attestationId].revoked) revert AlreadyRevoked();
    if (msg.sender != attestations[attestationId].portal) revert OnlyAttestingPortal();
    if (!isRevocable(attestations[attestationId].portal)) revert AttestationNotRevocable();

    attestations[attestationId].revoked = true;
    attestations[attestationId].revocationDate = uint64(block.timestamp);

    emit AttestationRevoked(attestationId);
  }

  /**
   * @notice Bulk revokes a list of attestations for the given identifiers
   * @param attestationIds the IDs of the attestations to revoke
   */
  function bulkRevoke(bytes32[] memory attestationIds) external {
    for (uint256 i = 0; i < attestationIds.length; i = uncheckedInc256(i)) {
      revoke(attestationIds[i]);
    }
  }

  /**
   * @notice Checks if an attestation is registered
   * @param attestationId the attestation identifier
   * @return true if the attestation is registered, false otherwise
   */
  function isRegistered(bytes32 attestationId) public view returns (bool) {
    return attestations[attestationId].attestationId != bytes32(0);
  }

  /**
   * @notice Checks whether a portal issues revocable attestations
   * @param portalId the portal address (ID)
   * @return true if the attestations issued by this portal are revocable, false otherwise
   */
  function isRevocable(address portalId) public view returns (bool) {
    PortalRegistry portalRegistry = PortalRegistry(router.getPortalRegistry());
    return portalRegistry.getPortalByAddress(portalId).isRevocable;
  }

  /**
   * @notice Gets an attestation by its identifier
   * @param attestationId the attestation identifier
   * @return the attestation
   */
  function getAttestation(bytes32 attestationId) public view returns (Attestation memory) {
    if (!isRegistered(attestationId)) revert AttestationNotAttested();
    return attestations[attestationId];
  }

  /**
   * @notice Increments the registry version
   * @return The new version number
   */
  function incrementVersionNumber() public onlyOwner returns (uint16) {
    ++version;
    emit VersionUpdated(version);
    return version;
  }

  /**
   * @notice Gets the registry version
   * @return The current version number
   */
  function getVersionNumber() public view returns (uint16) {
    return version;
  }

  /**
   * @notice Gets the attestation counter
   * @return The attestation counter
   */
  function getAttestationIdCounter() public view returns (uint32) {
    return attestationIdCounter;
  }

  /**
   * @notice Gets the chain prefix used to generate the attestation IDs
   * @return The chain prefix
   */
  function getChainPrefix() public view returns (uint256) {
    return chainPrefix;
  }

  /**
   * @notice Checks if an address owns a given attestation following ERC-1155
   * @param account The address of the token holder
   * @param id ID of the attestation
   * @return The _owner's balance of the attestations on a given attestation ID
   */
  function balanceOf(address account, uint256 id) public view returns (uint256) {
    bytes32 attestationId = generateAttestationId(id);
    Attestation memory attestation = attestations[attestationId];
    if (attestation.subject.length > 20 && keccak256(attestation.subject) == keccak256(abi.encode(account))) {
      return 1;
    }
    if (attestation.subject.length == 20 && keccak256(attestation.subject) == keccak256(abi.encodePacked(account))) {
      return 1;
    }
    return 0;
  }

  /**
   * @notice Get the balance of multiple account/attestation pairs following ERC-1155
   * @param accounts The addresses of the attestation holders
   * @param ids ID of the attestations
   * @return The _owner's balance of the attestation for a given address (i.e. balance for each (owner, id) pair)
   */
  function balanceOfBatch(address[] memory accounts, uint256[] memory ids) public view returns (uint256[] memory) {
    if (accounts.length != ids.length) revert ArrayLengthMismatch();
    uint256[] memory result = new uint256[](accounts.length);
    for (uint256 i = 0; i < accounts.length; i = uncheckedInc256(i)) {
      result[i] = balanceOf(accounts[i], ids[i]);
    }
    return result;
  }

  /**
   * @notice Generate an attestation ID, prefixed by the Verax chain identifier
   * @param id The attestation ID (coming after the chain prefix)
   * @return The attestation ID
   */
  function generateAttestationId(uint256 id) internal view returns (bytes32) {
    // Combine the chain prefix and the ID
    return bytes32(abi.encode(chainPrefix + id));
  }
}


The AttestationRegistry contract, part of a Consensys project, manages a registry of attestations (claims or credentials) by storing, updating, and revoking them. It supports bulk operations, versioning, and ensures only registered portals can issue attestations. It integrates with a Router for accessing related contracts and follows an upgradeable pattern.

Attestation Registry

// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;

/**
 * @notice This function is inspired by PADO Labs' codebase
 * solhint-disable-next-line max-line-length
 * https://github.com/pado-labs/offchain-data-hooks/blob/c6f37ad2a42d0eb40cf2295aed68ea3b94ee0925/src/hooks/Common.sol#L45
 * @dev A helper function to work with unchecked uint256 iterators in loops
 */
function uncheckedInc256(uint256 i) pure returns (uint256 j) {
  unchecked {
    j = i + 1;
  }
}

/**
 * @notice This function is inspired by PADO Labs' codebase
 * solhint-disable-next-line max-line-length
 * https://github.com/pado-labs/offchain-data-hooks/blob/c6f37ad2a42d0eb40cf2295aed68ea3b94ee0925/src/hooks/Common.sol#L45
 * @dev A helper function to work with unchecked uint32 iterators in loops
 */
function uncheckedInc32(uint32 i) pure returns (uint32 j) {
  unchecked {
    j = i + 1;
  }
}


// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;

import { AbstractPortal } from "./abstracts/AbstractPortal.sol";

/**
 * @title Default Portal
 * @author Consensys
 * @notice This contract aims to provide a default portal
 * @dev This Portal does not add any logic to the AbstractPortal
 */
contract DefaultPortal is AbstractPortal {
  /**
   * @notice Contract constructor
   * @param modules list of modules to use for the portal (can be empty)
   * @param router the Router's address
   * @dev This sets the addresses for the AttestationRegistry, ModuleRegistry and PortalRegistry
   */
  constructor(address[] memory modules, address router) AbstractPortal(modules, router) {}

  /// @inheritdoc AbstractPortal
  function withdraw(address payable to, uint256 amount) external override {}
}


Default Portal

_domain

_sender

_receiver

InvalidSignature

domain

chainId

verifyingContract

receiver

sender

// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;

import { AbstractModule } from "../../abstracts/AbstractModule.sol";
import { AttestationPayload } from "../../types/Structs.sol";

/**
 * @notice Definition of EIP-712 domain
 */
struct EIP712Domain {
  string name;
  string version;
  uint256 chainId;
  address verifyingContract;
}

contract ERC712Module is AbstractModule {
  EIP712Domain public domain;
  address public sender;
  address public receiver;

  error InvalidSignature();

  constructor(EIP712Domain memory _domain, address _sender, address _receiver) {
    domain = _domain;
    sender = _sender;
    receiver = _receiver;
  }

  function run(
    AttestationPayload memory /*attestationPayload*/,
    bytes memory validationPayload,
    address txSender,
    uint256 /*value*/
  ) public view override {
    (uint8 v, bytes32 r, bytes32 s) = abi.decode(validationPayload, (uint8, bytes32, bytes32));

    bytes32 DOMAIN_TYPE_HASH = keccak256(
      "EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"
    );
    bytes32 domainHash = keccak256(
      abi.encode(
        DOMAIN_TYPE_HASH,
        keccak256(bytes(domain.name)),
        keccak256(bytes(domain.version)),
        domain.chainId,
        domain.verifyingContract
      )
    );
    bytes32 TXN_TYPE_HASH = keccak256("Transaction(address from,address to,uint256 value)");
    bytes32 structHash = keccak256(abi.encode(TXN_TYPE_HASH, sender, receiver, uint256(1234)));
    bytes32 hash = keccak256(abi.encodePacked("\x19\x01", domainHash, structHash));

    address signer = ecrecover(hash, v, r, s);
    if (signer != txSender) {
      revert InvalidSignature();
    }
  }
}


MerkelProofVerifyFailed

// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;

import { AbstractModule } from "../../abstracts/AbstractModule.sol";
import { AttestationPayload } from "../../types/Structs.sol";
import { uncheckedInc256 } from "../../Common.sol";

contract MerkleProofModule is AbstractModule {
  error MerkelProofVerifyFailed();

  /**
   * @inheritdoc AbstractModule
   * @notice This method is used to run the module's validation logic
   * @param attestationPayload - AttestationPayload containing the user address as `subject`
   *                             and nonce as `attestationData`
   * @param validationPayload - validationPayload containing the serialized hash.The last one is the 'Root'.
   */
  function run(
    AttestationPayload memory attestationPayload,
    bytes memory validationPayload,
    address /*txSender*/,
    uint256 /*value*/
  ) public pure override {
    bytes32[] memory proof = abi.decode(validationPayload, (bytes32[]));
    bytes32 hash = bytes32(attestationPayload.attestationData);
    /*
     * @notice We send the hardcoded third leaf to verify.
     */
    uint256 index = 2;
    for (uint256 i = index + 1; i < proof.length; i = uncheckedInc256(i)) {
      bytes32 proofElement = proof[i];

      if (index % 2 == 0) {
        hash = keccak256(abi.encodePacked(hash, proofElement));
      } else {
        hash = keccak256(abi.encodePacked(proofElement, hash));
      }
      index = index / 2;
      if (index == 0) {
        break;
      }
    }

    if (hash != proof[proof.length - 1]) {
      revert MerkelProofVerifyFailed();
    }
  }
}


NoBulkRevocation

NoRevocation

ReferenceAttestationNotRegistered

attestationRequest

attestationsRequests

// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;

import { AbstractPortal } from "../../abstracts/AbstractPortal.sol";
import { AttestationPayload } from "../../types/Structs.sol";
import { uncheckedInc256 } from "../../Common.sol";

/**
 * @title EAS Portal
 * @author Consensys
 * @notice This is an example of how to maintain interoperability with EAS - https://attest.sh
 */
contract EASPortal is AbstractPortal {
  // @notice This struct is defined in EAS's contracts' codebase
  // solhint-disable-next-line max-line-length
  // this definition was taken from: https://github.com/ethereum-attestation-service/eas-contracts/blob/master/contracts/IEAS.sol#L9
  struct AttestationRequestData {
    address recipient;
    uint64 expirationTime;
    bool revocable;
    bytes32 refUID;
    bytes data;
    uint256 value;
  }

  // @notice This struct is defined in EAS's contracts' codebase
  // solhint-disable-next-line max-line-length
  // definition taken from: https://github.com/ethereum-attestation-service/eas-contracts/blob/master/contracts/IEAS.sol#L19
  struct AttestationRequest {
    bytes32 schema;
    AttestationRequestData data;
  }

  bytes32 private _relationshipSchemaId = 0x89bd76e17fd84df8e1e448fa1b46dd8d97f7e8e806552b003f8386a5aebcb9f0;

  /// @notice Error thrown when reference attestation with refUID is not registered
  error ReferenceAttestationNotRegistered();
  /// @notice Error thrown when trying to revoke an attestation
  error NoRevocation();
  /// @notice Error thrown when trying to bulk revoke attestations
  error NoBulkRevocation();

  constructor(address[] memory modules, address router) AbstractPortal(modules, router) {}

  /// @inheritdoc AbstractPortal
  function withdraw(address payable to, uint256 amount) external override {}

  /**
   * @notice Issues a Verax attestation based on an EAS attestation
   * @param attestationRequest the EAS payload to attest
   * @dev If a related EAS attestation exists, it will also be attested on Verax and linked via the dedicated Schema
   */
  function attest(AttestationRequest memory attestationRequest) public payable {
    bytes[] memory validationPayload = new bytes[](0);

    AttestationPayload memory attestationPayload = AttestationPayload(
      attestationRequest.schema,
      attestationRequest.data.expirationTime,
      abi.encodePacked(attestationRequest.data.recipient),
      attestationRequest.data.data
    );
    super.attest(attestationPayload, validationPayload);
    // if refUID exists then create relationship attestation
    if (attestationRequest.data.refUID != 0) {
      if (!attestationRegistry.isRegistered(attestationRequest.data.refUID)) {
        revert ReferenceAttestationNotRegistered();
      }

      uint32 attestationIdCounter = attestationRegistry.getAttestationIdCounter();
      bytes32 attestationId = bytes32(abi.encode(attestationIdCounter));

      AttestationPayload memory relationshipAttestationPayload = AttestationPayload(
        _relationshipSchemaId,
        attestationRequest.data.expirationTime,
        abi.encodePacked(attestationRequest.data.refUID),
        abi.encode(attestationId, "EASrefUID", attestationRequest.data.refUID)
      );

      super.attest(relationshipAttestationPayload, validationPayload);
    }
  }

  /**
   * @notice Issues Verax attestations in bulk, based on a list of EAS attestations
   * @param attestationsRequests the EAS payloads to attest
   */
  function bulkAttest(AttestationRequest[] memory attestationsRequests) external payable {
    for (uint256 i = 0; i < attestationsRequests.length; i = uncheckedInc256(i)) {
      attest(attestationsRequests[i]);
    }
  }

  /**
   * @inheritdoc AbstractPortal
   * @notice This portal doesn't allow for an attestation to be revoked
   */
  function _onRevoke(bytes32 /*attestationId*/) internal pure override {
    revert NoRevocation();
  }

  /**
   * @inheritdoc AbstractPortal
   * @notice This portal doesn't allow for attestations to be revoked
   */
  function _onBulkRevoke(bytes32[] memory /*attestationIds*/) internal pure override {
    revert NoBulkRevocation();
  }
}


EAS Portal

// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;

import { IERC721, ERC721 } from "openzeppelin-contracts/contracts/token/ERC721/ERC721.sol";
import { IERC165 } from "openzeppelin-contracts/contracts/utils/introspection/ERC165.sol";
import { AbstractPortal } from "../../abstracts/AbstractPortal.sol";
import { Attestation, AttestationPayload } from "../../types/Structs.sol";
import { IPortal } from "../../interfaces/IPortal.sol";

/**
 * @title NFT Portal
 * @author Consensys
 * @notice This contract aims to provide ERC 721 compatibility
 * @dev This Portal implements parts of ERC 721 - balanceOf and ownerOf functions
 */
contract NFTPortal is AbstractPortal, ERC721 {
  mapping(bytes owner => uint256 numberOfAttestations) private numberOfAttestationsPerOwner;

  constructor(
    address[] memory modules,
    address router
  ) AbstractPortal(modules, router) ERC721("NFTPortal", "NFTPortal") {}

  /**
   * @notice Count all attestations assigned to an owner
   * @param owner An address for whom to query the balance
   * @return The number of attestations owned by `owner`, possibly zero
   */
  function balanceOf(address owner) public view virtual override returns (uint256) {
    return numberOfAttestationsPerOwner[abi.encode(owner)];
  }

  /**
   * @notice Find the owner of an attestation
   * @param tokenId The identifier for an attestation
   * @return The address of the owner of the attestation
   */
  function ownerOf(uint256 tokenId) public view virtual override returns (address) {
    bytes32 attestationId = bytes32(tokenId);
    Attestation memory attestation = attestationRegistry.getAttestation(attestationId);
    return abi.decode(attestation.subject, (address));
  }

  /**
   * @notice Method run before a payload is attested
   * @param attestationPayload the attestation payload supposed to be attested
   */
  function _onAttest(
    AttestationPayload memory attestationPayload,
    address /*attester*/,
    uint256 /*value*/
  ) internal override {
    numberOfAttestationsPerOwner[attestationPayload.subject]++;
  }

  function withdraw(address payable to, uint256 amount) external override {}

  /**
   * @notice Verifies that a specific interface is implemented by the Portal, following ERC-165 specification
   * @param interfaceID the interface identifier checked in this call
   * @return The list of modules addresses linked to the Portal
   */
  function supportsInterface(bytes4 interfaceID) public pure virtual override(AbstractPortal, ERC721) returns (bool) {
    return
      interfaceID == type(AbstractPortal).interfaceId ||
      interfaceID == type(IPortal).interfaceId ||
      interfaceID == type(IERC165).interfaceId ||
      interfaceID == type(IERC721).interfaceId;
  }
}


NFT Portal

// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;

/// @notice A struct representing a single attestation.
// solhint-disable-next-line max-line-length
// this definition was taken from: https://github.com/ethereum-attestation-service/eas-contracts/blob/master/contracts/Common.sol#L25
struct Attestation {
  bytes32 uid; // A unique identifier of the attestation.
  bytes32 schema; // The unique identifier of the schema.
  uint64 time; // The time when the attestation was created (Unix timestamp).
  uint64 expirationTime; // The time when the attestation expires (Unix timestamp).
  uint64 revocationTime; // The time when the attestation was revoked (Unix timestamp).
  bytes32 refUID; // The UID of the related attestation.
  address recipient; // The recipient of the attestation.
  address attester; // The attester/sender of the attestation.
  bool revocable; // Whether the attestation is revocable.
  bytes data; // Custom attestation data.
}

/// @title IEAS
/// @notice EAS - Ethereum Attestation Service interface.
// solhint-disable-next-line max-line-length
// this definition was taken from: https://github.com/ethereum-attestation-service/eas-contracts/blob/master/contracts/IEAS.sol#L86
interface IEAS {
  /// @notice Returns an existing attestation by UID.
  /// @param uid The UID of the attestation to retrieve.
  /// @return The attestation data members.
  function getAttestation(bytes32 uid) external view returns (Attestation memory);
}


IEAS

// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;

import { IERC165 } from "openzeppelin-contracts/contracts/utils/introspection/ERC165.sol";

/**
 * @title IPortal
 * @author Consensys
 * @notice This contract is the interface to be implemented by any Portal.
 *         NOTE: A portal must implement this interface to registered on
 *         the PortalRegistry contract.
 */
interface IPortal is IERC165 {
  /**
   * @notice Get all the modules addresses used by the Portal
   * @return The list of modules addresses linked to the Portal
   */
  function getModules() external view returns (address[] memory);

  /**
   * @notice Defines the address of the entity issuing attestations to the subject
   * @dev We strongly encourage a reflection when implementing this method
   */
  function getAttester() external view returns (address);
}


IPortal

getAttestationRegistry

getModuleRegistry

getPortalRegistry

getSchemaRegistry

// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;

/**
 * @title Router
 * @author Consensys
 * @notice This contract aims to provides a single entrypoint for the Verax registries
 */
interface IRouter {
  /**
   * @notice Gives the address for the AttestationRegistry contract
   * @return The current address of the AttestationRegistry contract
   */
  function getAttestationRegistry() external view returns (address);

  /**
   * @notice Gives the address for the ModuleRegistry contract
   * @return The current address of the ModuleRegistry contract
   */
  function getModuleRegistry() external view returns (address);

  /**
   * @notice Gives the address for the PortalRegistry contract
   * @return The current address of the PortalRegistry contract
   */
  function getPortalRegistry() external view returns (address);

  /**
   * @notice Gives the address for the SchemaRegistry contract
   * @return The current address of the SchemaRegistry contract
   */
  function getSchemaRegistry() external view returns (address);
}


Router

AttestationPayloadMissing

ModuleAddressInvalid

ModuleAlreadyExists

ModuleInvalid

ModuleNameMissing

ModuleNotRegistered

ModuleValidationPayloadMismatch

OnlyIssuer

description

moduleAddress

ModuleRegistered

modulesAddresses

bulkRunModules

getModulesNumber

contractAddress

isContractAddress

moduleAddresses

register

runModules

// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;

import { AttestationPayload, Module } from "./types/Structs.sol";
import { AbstractModule } from "./abstracts/AbstractModule.sol";
import { OwnableUpgradeable } from "openzeppelin-contracts-upgradeable/contracts/access/OwnableUpgradeable.sol";
// solhint-disable-next-line max-line-length
import { ERC165CheckerUpgradeable } from "openzeppelin-contracts-upgradeable/contracts/utils/introspection/ERC165CheckerUpgradeable.sol";
import { PortalRegistry } from "./PortalRegistry.sol";
import { IRouter } from "./interfaces/IRouter.sol";
import { uncheckedInc32 } from "./Common.sol";

/**
 * @title Module Registry
 * @author Consensys
 * @notice This contract aims to manage the Modules used by the Portals, including their discoverability
 */
contract ModuleRegistry is OwnableUpgradeable {
  IRouter public router;
  /// @dev The list of Modules, accessed by their address
  mapping(address id => Module module) public modules;
  /// @dev The list of Module addresses
  address[] public moduleAddresses;

  /// @notice Error thrown when an invalid Router address is given
  error RouterInvalid();
  /// @notice Error thrown when a non-issuer tries to call a method that can only be called by an issuer
  error OnlyIssuer();
  /// @notice Error thrown when an identical Module was already registered
  error ModuleAlreadyExists();
  /// @notice Error thrown when attempting to add a Module without a name
  error ModuleNameMissing();
  /// @notice Error thrown when attempting to add a Module without an address of deployed smart contract
  error ModuleAddressInvalid();
  /// @notice Error thrown when attempting to add a Module which has not implemented the IModule interface
  error ModuleInvalid();
  /// @notice Error thrown when attempting to run modules with no attestation payload provided
  error AttestationPayloadMissing();
  /// @notice Error thrown when module is not registered
  error ModuleNotRegistered();
  /// @notice Error thrown when module addresses and validation payload length mismatch
  error ModuleValidationPayloadMismatch();

  /// @notice Event emitted when a Module is registered
  event ModuleRegistered(string name, string description, address moduleAddress);

  /// @custom:oz-upgrades-unsafe-allow constructor
  constructor() {
    _disableInitializers();
  }

  /**
   * @notice Contract initialization
   */
  function initialize() public initializer {
    __Ownable_init();
  }

  /**
   * @notice Checks if the caller is a registered issuer.
   * @param issuer the issuer address
   */
  modifier onlyIssuers(address issuer) {
    bool isIssuerRegistered = PortalRegistry(router.getPortalRegistry()).isIssuer(issuer);
    if (!isIssuerRegistered) revert OnlyIssuer();
    _;
  }

  /**
   * @notice Changes the address for the Router
   * @dev Only the registry owner can call this method
   */
  function updateRouter(address _router) public onlyOwner {
    if (_router == address(0)) revert RouterInvalid();
    router = IRouter(_router);
  }

  /**
   * Check if address is smart contract and not EOA
   * @param contractAddress address to be verified
   * @return the result as true if it is a smart contract else false
   */
  function isContractAddress(address contractAddress) public view returns (bool) {
    return contractAddress.code.length > 0;
  }

  /**
   * @notice Registers a Module, with its metadata and run some checks:
   * - mandatory name
   * - mandatory module's deployed smart contract address
   * - the module must be unique
   * @param name the module name
   * @param description the module description
   * @param moduleAddress the address of the deployed smart contract
   * @dev the module is stored in a mapping, the number of modules is incremented and an event is emitted
   */
  function register(
    string memory name,
    string memory description,
    address moduleAddress
  ) public onlyIssuers(msg.sender) {
    if (bytes(name).length == 0) revert ModuleNameMissing();
    // Check if moduleAddress is a smart contract address
    if (!isContractAddress(moduleAddress)) revert ModuleAddressInvalid();
    // Check if module has implemented AbstractModule
    if (!ERC165CheckerUpgradeable.supportsInterface(moduleAddress, type(AbstractModule).interfaceId)) {
      revert ModuleInvalid();
    }
    // Module address is used to identify uniqueness of the module
    if (bytes(modules[moduleAddress].name).length > 0) revert ModuleAlreadyExists();

    modules[moduleAddress] = Module(moduleAddress, name, description);
    moduleAddresses.push(moduleAddress);
    emit ModuleRegistered(name, description, moduleAddress);
  }

  /**
   * @notice Executes the run method for all given Modules that are registered
   * @param modulesAddresses the addresses of the registered modules
   * @param attestationPayload the payload to attest
   * @param validationPayloads the payloads to check for each module (one payload per module)
   * @dev check if modules are registered and execute run method for each module
   */
  function runModules(
    address[] memory modulesAddresses,
    AttestationPayload memory attestationPayload,
    bytes[] memory validationPayloads,
    uint256 value
  ) public {
    // If no modules provided, bypass module validation
    if (modulesAddresses.length == 0) return;
    // Each module involved must have a corresponding item from the validation payload
    if (modulesAddresses.length != validationPayloads.length) revert ModuleValidationPayloadMismatch();

    // For each module check if it is registered and call run method
    for (uint32 i = 0; i < modulesAddresses.length; i = uncheckedInc32(i)) {
      if (!isRegistered(modulesAddresses[i])) revert ModuleNotRegistered();
      AbstractModule(modulesAddresses[i]).run(attestationPayload, validationPayloads[i], tx.origin, value);
    }
  }

  /**
   * @notice Executes the modules validation for all attestations payloads for all given Modules that are registered
   * @param modulesAddresses the addresses of the registered modules
   * @param attestationsPayloads the payloads to attest
   * @param validationPayloads the payloads to check for each module
   * @dev NOTE: Currently the bulk run modules does not handle payable modules
   *            a default value of 0 is used.
   */
  function bulkRunModules(
    address[] memory modulesAddresses,
    AttestationPayload[] memory attestationsPayloads,
    bytes[][] memory validationPayloads
  ) public {
    for (uint32 i = 0; i < attestationsPayloads.length; i = uncheckedInc32(i)) {
      runModules(modulesAddresses, attestationsPayloads[i], validationPayloads[i], 0);
    }
  }

  /**
   * @notice Get the number of Modules managed by the contract
   * @return The number of Modules already registered
   * @dev Returns the length of the `moduleAddresses` array
   */
  function getModulesNumber() public view returns (uint256) {
    return moduleAddresses.length;
  }

  /**
   * @notice Checks that a module is registered in the module registry
   * @param moduleAddress The address of the Module to check
   * @return True if the Module is registered, False otherwise
   */
  function isRegistered(address moduleAddress) public view returns (bool) {
    return bytes(modules[moduleAddress].name).length > 0;
  }
}


the module name

Module Registry

PortalAddressInvalid

PortalAlreadyExists

PortalDescriptionMissing

PortalInvalid

PortalNameMissing

PortalNotRegistered

PortalOwnerNameMissing

issuerAddress

IssuerAdded

IssuerRemoved

portalAddress

PortalRegistered

PortalRevoked

ownerName

deployDefaultPortal

getPortalByAddress

getPortalsCount

// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;

import { OwnableUpgradeable } from "openzeppelin-contracts-upgradeable/contracts/access/OwnableUpgradeable.sol";
// solhint-disable-next-line max-line-length
import { ERC165CheckerUpgradeable } from "openzeppelin-contracts-upgradeable/contracts/utils/introspection/ERC165CheckerUpgradeable.sol";
import { AbstractPortal } from "./abstracts/AbstractPortal.sol";
import { DefaultPortal } from "./DefaultPortal.sol";
import { SchemaRegistry } from "./SchemaRegistry.sol";
import { Portal } from "./types/Structs.sol";
import { IRouter } from "./interfaces/IRouter.sol";
import { IPortal } from "./interfaces/IPortal.sol";
import { uncheckedInc256 } from "./Common.sol";

/**
 * @title Portal Registry
 * @author Consensys
 * @notice This contract aims to manage the Portals used by attestation issuers
 */
contract PortalRegistry is OwnableUpgradeable {
  IRouter public router;

  mapping(address id => Portal portal) private portals;

  mapping(address issuerAddress => bool isIssuer) private issuers;

  address[] private portalAddresses;

  /// @notice Error thrown when an invalid Router address is given
  error RouterInvalid();
  /// @notice Error thrown when a non-issuer tries to call a method that can only be called by an issuer
  error OnlyIssuer();
  /// @notice Error thrown when attempting to register a Portal twice
  error PortalAlreadyExists();
  /// @notice Error thrown when attempting to register a Portal that is not a smart contract
  error PortalAddressInvalid();
  /// @notice Error thrown when attempting to register a Portal with an empty name
  error PortalNameMissing();
  /// @notice Error thrown when attempting to register a Portal with an empty description
  error PortalDescriptionMissing();
  /// @notice Error thrown when attempting to register a Portal with an empty owner name
  error PortalOwnerNameMissing();
  /// @notice Error thrown when attempting to register a Portal that does not implement IPortal interface
  error PortalInvalid();
  /// @notice Error thrown when attempting to get a Portal that is not registered
  error PortalNotRegistered();

  /// @notice Event emitted when a Portal is registered
  event PortalRegistered(string name, string description, address portalAddress);
  /// @notice Event emitted when a new issuer is added
  event IssuerAdded(address issuerAddress);
  /// @notice Event emitted when the issuer is removed
  event IssuerRemoved(address issuerAddress);
  /// @notice Event emitted when a Portal is revoked
  event PortalRevoked(address portalAddress);

  /// @custom:oz-upgrades-unsafe-allow constructor
  constructor() {
    _disableInitializers();
  }

  /**
   * @notice Contract initialization
   */
  function initialize() public initializer {
    __Ownable_init();
  }

  /**
   * @notice Changes the address for the Router
   * @dev Only the registry owner can call this method
   */
  function updateRouter(address _router) public onlyOwner {
    if (_router == address(0)) revert RouterInvalid();
    router = IRouter(_router);
  }

  /**
   * @notice Registers an address as been an issuer
   * @param issuer the address to register as an issuer
   */
  function setIssuer(address issuer) public onlyOwner {
    issuers[issuer] = true;
    // Emit event
    emit IssuerAdded(issuer);
  }

  /**
   * @notice Revokes issuer status from an address
   * @param issuer the address to be revoked as an issuer
   */
  function removeIssuer(address issuer) public onlyOwner {
    issuers[issuer] = false;
    SchemaRegistry(router.getSchemaRegistry()).updateMatchingSchemaIssuers(issuer, msg.sender);
    // Emit event
    emit IssuerRemoved(issuer);
  }

  /**
   * @notice Checks if a given address is an issuer
   * @return A flag indicating whether the given address is an issuer
   */
  function isIssuer(address issuer) public view returns (bool) {
    return issuers[issuer];
  }

  /**
   * @notice Checks if the caller is a registered issuer.
   * @param issuer the issuer address
   */
  modifier onlyIssuers(address issuer) {
    if (!isIssuer(issuer)) revert OnlyIssuer();
    _;
  }

  /**
   * @notice Registers a Portal to the PortalRegistry
   * @param id the portal address
   * @param name the portal name
   * @param description the portal description
   * @param isRevocable whether the portal issues revocable attestations
   * @param ownerName name of this portal's owner
   */
  function register(
    address id,
    string memory name,
    string memory description,
    bool isRevocable,
    string memory ownerName
  ) public onlyIssuers(msg.sender) {
    // Check if portal already exists
    if (portals[id].id != address(0)) revert PortalAlreadyExists();

    // Check if portal is a smart contract
    if (!isContractAddress(id)) revert PortalAddressInvalid();

    // Check if name is not empty
    if (bytes(name).length == 0) revert PortalNameMissing();

    // Check if description is not empty
    if (bytes(description).length == 0) revert PortalDescriptionMissing();

    // Check if the owner's name is not empty
    if (bytes(ownerName).length == 0) revert PortalOwnerNameMissing();

    // Check if portal has implemented AbstractPortal
    if (!ERC165CheckerUpgradeable.supportsInterface(id, type(IPortal).interfaceId)) revert PortalInvalid();

    // Get the array of modules implemented by the portal
    address[] memory modules = AbstractPortal(id).getModules();

    // Add portal to mapping
    Portal memory newPortal = Portal(id, msg.sender, modules, isRevocable, name, description, ownerName);
    portals[id] = newPortal;
    portalAddresses.push(id);

    // Emit event
    emit PortalRegistered(name, description, id);
  }

  /**
   * @notice Revokes a Portal from the PortalRegistry
   * @param id the portal address
   * @dev Only the registry owner can call this method
   */
  function revoke(address id) public onlyOwner {
    if (!isRegistered(id)) revert PortalNotRegistered();

    portals[id] = Portal(address(0), address(0), new address[](0), false, "", "", "");

    uint256 portalAddressIndex;
    for (uint256 i = 0; i < portalAddresses.length; i = uncheckedInc256(i)) {
      if (portalAddresses[i] == id) {
        portalAddressIndex = i;
      }
    }

    if (portalAddressIndex >= portalAddresses.length) {
      revert PortalNotRegistered();
    }

    portalAddresses[portalAddressIndex] = portalAddresses[portalAddresses.length - 1];
    portalAddresses.pop();

    emit PortalRevoked(id);
  }

  /**
   * @notice Deploys and registers a clone of default portal
   * @param modules the modules addresses
   * @param name the portal name
   * @param description the portal description
   * @param ownerName name of this portal's owner
   */
  function deployDefaultPortal(
    address[] calldata modules,
    string memory name,
    string memory description,
    bool isRevocable,
    string memory ownerName
  ) external onlyIssuers(msg.sender) {
    DefaultPortal defaultPortal = new DefaultPortal(modules, address(router));
    register(address(defaultPortal), name, description, isRevocable, ownerName);
  }

  /**
   * @notice Get a Portal by its address
   * @param id The address of the Portal
   * @return The Portal
   */
  function getPortalByAddress(address id) public view returns (Portal memory) {
    if (!isRegistered(id)) revert PortalNotRegistered();
    return portals[id];
  }

  /**
   * @notice Check if a Portal is registered
   * @param id The address of the Portal
   * @return True if the Portal is registered, false otherwise
   */
  function isRegistered(address id) public view returns (bool) {
    return portals[id].id != address(0);
  }

  /**
   * @notice Get the number of Portals managed by the contract
   * @return The number of Portals already registered
   * @dev Returns the length of the `portalAddresses` array
   */
  function getPortalsCount() public view returns (uint256) {
    return portalAddresses.length;
  }

  /**
   * Check if address is smart contract and not EOA
   * @param contractAddress address to be verified
   * @return the result as true if it is a smart contract else false
   */
  function isContractAddress(address contractAddress) internal view returns (bool) {
    return contractAddress.code.length > 0;
  }
}


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