ETH Price: $2,428.97 (-4.90%)

Transaction Decoder

Block:
20912013 at Oct-07-2024 06:53:23 AM +UTC
Transaction Fee:
0.000527407331704473 ETH $1.28
Gas Used:
53,317 Gas / 9.891916869 Gwei

Emitted Events:

278 TransparentUpgradeableProxy.0x8c5be1e5ebec7d5bd14f71427d1e84f3dd0314c0f7b2291e5b200ac8c7c3b925( 0x8c5be1e5ebec7d5bd14f71427d1e84f3dd0314c0f7b2291e5b200ac8c7c3b925, 0x000000000000000000000000789debec22adda4383a7428808784e26fd50bde8, 0x000000000000000000000000000000000022d473030f116ddee9f6b43ac78ba3, 000000000000000000000000000000000000000000000000036c081cf15c5000 )

Account State Difference:

  Address   Before After State Difference Code
(Titan Builder)
15.903494545800881193 Eth15.903549594957392421 Eth0.000055049156511228
0x789DEBEC...6Fd50bdE8
0.089486533868628437 Eth
Nonce: 294
0.088959126536923964 Eth
Nonce: 295
0.000527407331704473
0xd5F7838F...28bB0ADfa

Execution Trace

TransparentUpgradeableProxy.095ea7b3( )
  • METH.approve( spender=0x000000000022D473030F116dDEE9F6B43aC78BA3, amount=246581000000000000 ) => ( True )
    File 1 of 2: TransparentUpgradeableProxy
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.8.3) (proxy/transparent/TransparentUpgradeableProxy.sol)
    pragma solidity ^0.8.0;
    import "../ERC1967/ERC1967Proxy.sol";
    /**
     * @dev Interface for {TransparentUpgradeableProxy}. In order to implement transparency, {TransparentUpgradeableProxy}
     * does not implement this interface directly, and some of its functions are implemented by an internal dispatch
     * mechanism. The compiler is unaware that these functions are implemented by {TransparentUpgradeableProxy} and will not
     * include them in the ABI so this interface must be used to interact with it.
     */
    interface ITransparentUpgradeableProxy is IERC1967 {
        function admin() external view returns (address);
        function implementation() external view returns (address);
        function changeAdmin(address) external;
        function upgradeTo(address) external;
        function upgradeToAndCall(address, bytes memory) external payable;
    }
    /**
     * @dev This contract implements a proxy that is upgradeable by an admin.
     *
     * To avoid https://medium.com/nomic-labs-blog/malicious-backdoors-in-ethereum-proxies-62629adf3357[proxy selector
     * clashing], which can potentially be used in an attack, this contract uses the
     * https://blog.openzeppelin.com/the-transparent-proxy-pattern/[transparent proxy pattern]. This pattern implies two
     * things that go hand in hand:
     *
     * 1. If any account other than the admin calls the proxy, the call will be forwarded to the implementation, even if
     * that call matches one of the admin functions exposed by the proxy itself.
     * 2. If the admin calls the proxy, it can access the admin functions, but its calls will never be forwarded to the
     * implementation. If the admin tries to call a function on the implementation it will fail with an error that says
     * "admin cannot fallback to proxy target".
     *
     * These properties mean that the admin account can only be used for admin actions like upgrading the proxy or changing
     * the admin, so it's best if it's a dedicated account that is not used for anything else. This will avoid headaches due
     * to sudden errors when trying to call a function from the proxy implementation.
     *
     * Our recommendation is for the dedicated account to be an instance of the {ProxyAdmin} contract. If set up this way,
     * you should think of the `ProxyAdmin` instance as the real administrative interface of your proxy.
     *
     * NOTE: The real interface of this proxy is that defined in `ITransparentUpgradeableProxy`. This contract does not
     * inherit from that interface, and instead the admin functions are implicitly implemented using a custom dispatch
     * mechanism in `_fallback`. Consequently, the compiler will not produce an ABI for this contract. This is necessary to
     * fully implement transparency without decoding reverts caused by selector clashes between the proxy and the
     * implementation.
     *
     * WARNING: It is not recommended to extend this contract to add additional external functions. If you do so, the compiler
     * will not check that there are no selector conflicts, due to the note above. A selector clash between any new function
     * and the functions declared in {ITransparentUpgradeableProxy} will be resolved in favor of the new one. This could
     * render the admin operations inaccessible, which could prevent upgradeability. Transparency may also be compromised.
     */
    contract TransparentUpgradeableProxy is ERC1967Proxy {
        /**
         * @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and
         * optionally initialized with `_data` as explained in {ERC1967Proxy-constructor}.
         */
        constructor(address _logic, address admin_, bytes memory _data) payable ERC1967Proxy(_logic, _data) {
            _changeAdmin(admin_);
        }
        /**
         * @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.
         *
         * CAUTION: This modifier is deprecated, as it could cause issues if the modified function has arguments, and the
         * implementation provides a function with the same selector.
         */
        modifier ifAdmin() {
            if (msg.sender == _getAdmin()) {
                _;
            } else {
                _fallback();
            }
        }
        /**
         * @dev If caller is the admin process the call internally, otherwise transparently fallback to the proxy behavior
         */
        function _fallback() internal virtual override {
            if (msg.sender == _getAdmin()) {
                bytes memory ret;
                bytes4 selector = msg.sig;
                if (selector == ITransparentUpgradeableProxy.upgradeTo.selector) {
                    ret = _dispatchUpgradeTo();
                } else if (selector == ITransparentUpgradeableProxy.upgradeToAndCall.selector) {
                    ret = _dispatchUpgradeToAndCall();
                } else if (selector == ITransparentUpgradeableProxy.changeAdmin.selector) {
                    ret = _dispatchChangeAdmin();
                } else if (selector == ITransparentUpgradeableProxy.admin.selector) {
                    ret = _dispatchAdmin();
                } else if (selector == ITransparentUpgradeableProxy.implementation.selector) {
                    ret = _dispatchImplementation();
                } else {
                    revert("TransparentUpgradeableProxy: admin cannot fallback to proxy target");
                }
                assembly {
                    return(add(ret, 0x20), mload(ret))
                }
            } else {
                super._fallback();
            }
        }
        /**
         * @dev Returns the current admin.
         *
         * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
         * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
         * `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`
         */
        function _dispatchAdmin() private returns (bytes memory) {
            _requireZeroValue();
            address admin = _getAdmin();
            return abi.encode(admin);
        }
        /**
         * @dev Returns the current implementation.
         *
         * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
         * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
         * `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`
         */
        function _dispatchImplementation() private returns (bytes memory) {
            _requireZeroValue();
            address implementation = _implementation();
            return abi.encode(implementation);
        }
        /**
         * @dev Changes the admin of the proxy.
         *
         * Emits an {AdminChanged} event.
         */
        function _dispatchChangeAdmin() private returns (bytes memory) {
            _requireZeroValue();
            address newAdmin = abi.decode(msg.data[4:], (address));
            _changeAdmin(newAdmin);
            return "";
        }
        /**
         * @dev Upgrade the implementation of the proxy.
         */
        function _dispatchUpgradeTo() private returns (bytes memory) {
            _requireZeroValue();
            address newImplementation = abi.decode(msg.data[4:], (address));
            _upgradeToAndCall(newImplementation, bytes(""), false);
            return "";
        }
        /**
         * @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified
         * by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the
         * proxied contract.
         */
        function _dispatchUpgradeToAndCall() private returns (bytes memory) {
            (address newImplementation, bytes memory data) = abi.decode(msg.data[4:], (address, bytes));
            _upgradeToAndCall(newImplementation, data, true);
            return "";
        }
        /**
         * @dev Returns the current admin.
         *
         * CAUTION: This function is deprecated. Use {ERC1967Upgrade-_getAdmin} instead.
         */
        function _admin() internal view virtual returns (address) {
            return _getAdmin();
        }
        /**
         * @dev To keep this contract fully transparent, all `ifAdmin` functions must be payable. This helper is here to
         * emulate some proxy functions being non-payable while still allowing value to pass through.
         */
        function _requireZeroValue() private {
            require(msg.value == 0);
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.7.0) (proxy/ERC1967/ERC1967Proxy.sol)
    pragma solidity ^0.8.0;
    import "../Proxy.sol";
    import "./ERC1967Upgrade.sol";
    /**
     * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
     * implementation address that can be changed. This address is stored in storage in the location specified by
     * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
     * implementation behind the proxy.
     */
    contract ERC1967Proxy is Proxy, ERC1967Upgrade {
        /**
         * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
         *
         * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
         * function call, and allows initializing the storage of the proxy like a Solidity constructor.
         */
        constructor(address _logic, bytes memory _data) payable {
            _upgradeToAndCall(_logic, _data, false);
        }
        /**
         * @dev Returns the current implementation address.
         */
        function _implementation() internal view virtual override returns (address impl) {
            return ERC1967Upgrade._getImplementation();
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.6.0) (proxy/Proxy.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
     * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
     * be specified by overriding the virtual {_implementation} function.
     *
     * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
     * different contract through the {_delegate} function.
     *
     * The success and return data of the delegated call will be returned back to the caller of the proxy.
     */
    abstract contract Proxy {
        /**
         * @dev Delegates the current call to `implementation`.
         *
         * This function does not return to its internal call site, it will return directly to the external caller.
         */
        function _delegate(address implementation) internal virtual {
            assembly {
                // Copy msg.data. We take full control of memory in this inline assembly
                // block because it will not return to Solidity code. We overwrite the
                // Solidity scratch pad at memory position 0.
                calldatacopy(0, 0, calldatasize())
                // Call the implementation.
                // out and outsize are 0 because we don't know the size yet.
                let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
                // Copy the returned data.
                returndatacopy(0, 0, returndatasize())
                switch result
                // delegatecall returns 0 on error.
                case 0 {
                    revert(0, returndatasize())
                }
                default {
                    return(0, returndatasize())
                }
            }
        }
        /**
         * @dev This is a virtual function that should be overridden so it returns the address to which the fallback function
         * and {_fallback} should delegate.
         */
        function _implementation() internal view virtual returns (address);
        /**
         * @dev Delegates the current call to the address returned by `_implementation()`.
         *
         * This function does not return to its internal call site, it will return directly to the external caller.
         */
        function _fallback() internal virtual {
            _beforeFallback();
            _delegate(_implementation());
        }
        /**
         * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
         * function in the contract matches the call data.
         */
        fallback() external payable virtual {
            _fallback();
        }
        /**
         * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
         * is empty.
         */
        receive() external payable virtual {
            _fallback();
        }
        /**
         * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
         * call, or as part of the Solidity `fallback` or `receive` functions.
         *
         * If overridden should call `super._beforeFallback()`.
         */
        function _beforeFallback() internal virtual {}
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.8.3) (proxy/ERC1967/ERC1967Upgrade.sol)
    pragma solidity ^0.8.2;
    import "../beacon/IBeacon.sol";
    import "../../interfaces/IERC1967.sol";
    import "../../interfaces/draft-IERC1822.sol";
    import "../../utils/Address.sol";
    import "../../utils/StorageSlot.sol";
    /**
     * @dev This abstract contract provides getters and event emitting update functions for
     * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
     *
     * _Available since v4.1._
     */
    abstract contract ERC1967Upgrade is IERC1967 {
        // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
        bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
        /**
         * @dev Storage slot with the address of the current implementation.
         * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
         * validated in the constructor.
         */
        bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
        /**
         * @dev Returns the current implementation address.
         */
        function _getImplementation() internal view returns (address) {
            return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
        }
        /**
         * @dev Stores a new address in the EIP1967 implementation slot.
         */
        function _setImplementation(address newImplementation) private {
            require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
            StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
        }
        /**
         * @dev Perform implementation upgrade
         *
         * Emits an {Upgraded} event.
         */
        function _upgradeTo(address newImplementation) internal {
            _setImplementation(newImplementation);
            emit Upgraded(newImplementation);
        }
        /**
         * @dev Perform implementation upgrade with additional setup call.
         *
         * Emits an {Upgraded} event.
         */
        function _upgradeToAndCall(address newImplementation, bytes memory data, bool forceCall) internal {
            _upgradeTo(newImplementation);
            if (data.length > 0 || forceCall) {
                Address.functionDelegateCall(newImplementation, data);
            }
        }
        /**
         * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
         *
         * Emits an {Upgraded} event.
         */
        function _upgradeToAndCallUUPS(address newImplementation, bytes memory data, bool forceCall) internal {
            // Upgrades from old implementations will perform a rollback test. This test requires the new
            // implementation to upgrade back to the old, non-ERC1822 compliant, implementation. Removing
            // this special case will break upgrade paths from old UUPS implementation to new ones.
            if (StorageSlot.getBooleanSlot(_ROLLBACK_SLOT).value) {
                _setImplementation(newImplementation);
            } else {
                try IERC1822Proxiable(newImplementation).proxiableUUID() returns (bytes32 slot) {
                    require(slot == _IMPLEMENTATION_SLOT, "ERC1967Upgrade: unsupported proxiableUUID");
                } catch {
                    revert("ERC1967Upgrade: new implementation is not UUPS");
                }
                _upgradeToAndCall(newImplementation, data, forceCall);
            }
        }
        /**
         * @dev Storage slot with the admin of the contract.
         * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
         * validated in the constructor.
         */
        bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
        /**
         * @dev Returns the current admin.
         */
        function _getAdmin() internal view returns (address) {
            return StorageSlot.getAddressSlot(_ADMIN_SLOT).value;
        }
        /**
         * @dev Stores a new address in the EIP1967 admin slot.
         */
        function _setAdmin(address newAdmin) private {
            require(newAdmin != address(0), "ERC1967: new admin is the zero address");
            StorageSlot.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
        }
        /**
         * @dev Changes the admin of the proxy.
         *
         * Emits an {AdminChanged} event.
         */
        function _changeAdmin(address newAdmin) internal {
            emit AdminChanged(_getAdmin(), newAdmin);
            _setAdmin(newAdmin);
        }
        /**
         * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
         * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
         */
        bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
        /**
         * @dev Returns the current beacon.
         */
        function _getBeacon() internal view returns (address) {
            return StorageSlot.getAddressSlot(_BEACON_SLOT).value;
        }
        /**
         * @dev Stores a new beacon in the EIP1967 beacon slot.
         */
        function _setBeacon(address newBeacon) private {
            require(Address.isContract(newBeacon), "ERC1967: new beacon is not a contract");
            require(
                Address.isContract(IBeacon(newBeacon).implementation()),
                "ERC1967: beacon implementation is not a contract"
            );
            StorageSlot.getAddressSlot(_BEACON_SLOT).value = newBeacon;
        }
        /**
         * @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
         * not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
         *
         * Emits a {BeaconUpgraded} event.
         */
        function _upgradeBeaconToAndCall(address newBeacon, bytes memory data, bool forceCall) internal {
            _setBeacon(newBeacon);
            emit BeaconUpgraded(newBeacon);
            if (data.length > 0 || forceCall) {
                Address.functionDelegateCall(IBeacon(newBeacon).implementation(), data);
            }
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts v4.4.1 (proxy/beacon/IBeacon.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev This is the interface that {BeaconProxy} expects of its beacon.
     */
    interface IBeacon {
        /**
         * @dev Must return an address that can be used as a delegate call target.
         *
         * {BeaconProxy} will check that this address is a contract.
         */
        function implementation() external view returns (address);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev ERC-1967: Proxy Storage Slots. This interface contains the events defined in the ERC.
     *
     * _Available since v4.8.3._
     */
    interface IERC1967 {
        /**
         * @dev Emitted when the implementation is upgraded.
         */
        event Upgraded(address indexed implementation);
        /**
         * @dev Emitted when the admin account has changed.
         */
        event AdminChanged(address previousAdmin, address newAdmin);
        /**
         * @dev Emitted when the beacon is changed.
         */
        event BeaconUpgraded(address indexed beacon);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.5.0) (interfaces/draft-IERC1822.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev ERC1822: Universal Upgradeable Proxy Standard (UUPS) documents a method for upgradeability through a simplified
     * proxy whose upgrades are fully controlled by the current implementation.
     */
    interface IERC1822Proxiable {
        /**
         * @dev Returns the storage slot that the proxiable contract assumes is being used to store the implementation
         * address.
         *
         * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
         * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
         * function revert if invoked through a proxy.
         */
        function proxiableUUID() external view returns (bytes32);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.8.0) (utils/Address.sol)
    pragma solidity ^0.8.1;
    /**
     * @dev Collection of functions related to the address type
     */
    library 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 (last updated v4.7.0) (utils/StorageSlot.sol)
    // This file was procedurally generated from scripts/generate/templates/StorageSlot.js.
    pragma solidity ^0.8.0;
    /**
     * @dev Library for reading and writing primitive types to specific storage slots.
     *
     * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
     * This library helps with reading and writing to such slots without the need for inline assembly.
     *
     * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
     *
     * Example usage to set ERC1967 implementation slot:
     * ```solidity
     * contract ERC1967 {
     *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
     *
     *     function _getImplementation() internal view returns (address) {
     *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
     *     }
     *
     *     function _setImplementation(address newImplementation) internal {
     *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
     *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
     *     }
     * }
     * ```
     *
     * _Available since v4.1 for `address`, `bool`, `bytes32`, `uint256`._
     * _Available since v4.9 for `string`, `bytes`._
     */
    library StorageSlot {
        struct AddressSlot {
            address value;
        }
        struct BooleanSlot {
            bool value;
        }
        struct Bytes32Slot {
            bytes32 value;
        }
        struct Uint256Slot {
            uint256 value;
        }
        struct StringSlot {
            string value;
        }
        struct BytesSlot {
            bytes value;
        }
        /**
         * @dev Returns an `AddressSlot` with member `value` located at `slot`.
         */
        function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := slot
            }
        }
        /**
         * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
         */
        function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := slot
            }
        }
        /**
         * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
         */
        function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := slot
            }
        }
        /**
         * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
         */
        function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := slot
            }
        }
        /**
         * @dev Returns an `StringSlot` with member `value` located at `slot`.
         */
        function getStringSlot(bytes32 slot) internal pure returns (StringSlot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := slot
            }
        }
        /**
         * @dev Returns an `StringSlot` representation of the string storage pointer `store`.
         */
        function getStringSlot(string storage store) internal pure returns (StringSlot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := store.slot
            }
        }
        /**
         * @dev Returns an `BytesSlot` with member `value` located at `slot`.
         */
        function getBytesSlot(bytes32 slot) internal pure returns (BytesSlot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := slot
            }
        }
        /**
         * @dev Returns an `BytesSlot` representation of the bytes storage pointer `store`.
         */
        function getBytesSlot(bytes storage store) internal pure returns (BytesSlot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := store.slot
            }
        }
    }
    

    File 2 of 2: METH
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.20;
    import {Initializable} from "openzeppelin-upgradeable/proxy/utils/Initializable.sol";
    import {AccessControlEnumerableUpgradeable} from
        "openzeppelin-upgradeable/access/AccessControlEnumerableUpgradeable.sol";
    import {AccessControlEnumerable} from "openzeppelin/access/AccessControlEnumerable.sol";
    import {
        ERC20PermitUpgradeable,
        IERC20PermitUpgradeable
    } from "openzeppelin-upgradeable/token/ERC20/extensions/ERC20PermitUpgradeable.sol";
    import {IMETH} from "./interfaces/IMETH.sol";
    import {IStaking} from "./interfaces/IStaking.sol";
    import {IUnstakeRequestsManager} from "./interfaces/IUnstakeRequestsManager.sol";
    /// @title METH
    /// @notice METH is the ERC20 LSD token for the protocol.
    contract METH is Initializable, AccessControlEnumerableUpgradeable, ERC20PermitUpgradeable, IMETH {
        // Errors.
        error NotStakingContract();
        error NotUnstakeRequestsManagerContract();
        /// @notice The staking contract which has permissions to mint tokens.
        IStaking public stakingContract;
        /// @notice The unstake requests manager contract which has permissions to burn tokens.
        IUnstakeRequestsManager public unstakeRequestsManagerContract;
        /// @notice Configuration for contract initialization.
        struct Init {
            address admin;
            IStaking staking;
            IUnstakeRequestsManager unstakeRequestsManager;
        }
        constructor() {
            _disableInitializers();
        }
        /// @notice Inititalizes the contract.
        /// @dev MUST be called during the contract upgrade to set up the proxies state.
        function initialize(Init memory init) external initializer {
            __AccessControlEnumerable_init();
            __ERC20_init("mETH", "mETH");
            __ERC20Permit_init("mETH");
            _grantRole(DEFAULT_ADMIN_ROLE, init.admin);
            stakingContract = init.staking;
            unstakeRequestsManagerContract = init.unstakeRequestsManager;
        }
        /// @inheritdoc IMETH
        /// @dev Expected to be called during the stake operation.
        function mint(address staker, uint256 amount) external {
            if (msg.sender != address(stakingContract)) {
                revert NotStakingContract();
            }
            _mint(staker, amount);
        }
        /// @inheritdoc IMETH
        /// @dev Expected to be called when a user has claimed their unstake request.
        function burn(uint256 amount) external {
            if (msg.sender != address(unstakeRequestsManagerContract)) {
                revert NotUnstakeRequestsManagerContract();
            }
            _burn(msg.sender, amount);
        }
        /// @dev See {IERC20Permit-nonces}.
        function nonces(address owner)
            public
            view
            virtual
            override(ERC20PermitUpgradeable, IERC20PermitUpgradeable)
            returns (uint256)
        {
            return ERC20PermitUpgradeable.nonces(owner);
        }
    }
    // 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 v4.5.0) (access/AccessControlEnumerable.sol)
    pragma solidity ^0.8.0;
    import "./IAccessControlEnumerableUpgradeable.sol";
    import "./AccessControlUpgradeable.sol";
    import "../utils/structs/EnumerableSetUpgradeable.sol";
    import "../proxy/utils/Initializable.sol";
    /**
     * @dev Extension of {AccessControl} that allows enumerating the members of each role.
     */
    abstract contract AccessControlEnumerableUpgradeable is Initializable, IAccessControlEnumerableUpgradeable, AccessControlUpgradeable {
        function __AccessControlEnumerable_init() internal onlyInitializing {
        }
        function __AccessControlEnumerable_init_unchained() internal onlyInitializing {
        }
        using EnumerableSetUpgradeable for EnumerableSetUpgradeable.AddressSet;
        mapping(bytes32 => EnumerableSetUpgradeable.AddressSet) private _roleMembers;
        /**
         * @dev See {IERC165-supportsInterface}.
         */
        function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
            return interfaceId == type(IAccessControlEnumerableUpgradeable).interfaceId || super.supportsInterface(interfaceId);
        }
        /**
         * @dev Returns one of the accounts that have `role`. `index` must be a
         * value between 0 and {getRoleMemberCount}, non-inclusive.
         *
         * Role bearers are not sorted in any particular way, and their ordering may
         * change at any point.
         *
         * WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure
         * you perform all queries on the same block. See the following
         * https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296[forum post]
         * for more information.
         */
        function getRoleMember(bytes32 role, uint256 index) public view virtual override returns (address) {
            return _roleMembers[role].at(index);
        }
        /**
         * @dev Returns the number of accounts that have `role`. Can be used
         * together with {getRoleMember} to enumerate all bearers of a role.
         */
        function getRoleMemberCount(bytes32 role) public view virtual override returns (uint256) {
            return _roleMembers[role].length();
        }
        /**
         * @dev Overload {_grantRole} to track enumerable memberships
         */
        function _grantRole(bytes32 role, address account) internal virtual override {
            super._grantRole(role, account);
            _roleMembers[role].add(account);
        }
        /**
         * @dev Overload {_revokeRole} to track enumerable memberships
         */
        function _revokeRole(bytes32 role, address account) internal virtual override {
            super._revokeRole(role, account);
            _roleMembers[role].remove(account);
        }
        /**
         * @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 v4.5.0) (access/AccessControlEnumerable.sol)
    pragma solidity ^0.8.0;
    import "./IAccessControlEnumerable.sol";
    import "./AccessControl.sol";
    import "../utils/structs/EnumerableSet.sol";
    /**
     * @dev Extension of {AccessControl} that allows enumerating the members of each role.
     */
    abstract contract AccessControlEnumerable is IAccessControlEnumerable, AccessControl {
        using EnumerableSet for EnumerableSet.AddressSet;
        mapping(bytes32 => EnumerableSet.AddressSet) private _roleMembers;
        /**
         * @dev See {IERC165-supportsInterface}.
         */
        function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
            return interfaceId == type(IAccessControlEnumerable).interfaceId || super.supportsInterface(interfaceId);
        }
        /**
         * @dev Returns one of the accounts that have `role`. `index` must be a
         * value between 0 and {getRoleMemberCount}, non-inclusive.
         *
         * Role bearers are not sorted in any particular way, and their ordering may
         * change at any point.
         *
         * WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure
         * you perform all queries on the same block. See the following
         * https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296[forum post]
         * for more information.
         */
        function getRoleMember(bytes32 role, uint256 index) public view virtual override returns (address) {
            return _roleMembers[role].at(index);
        }
        /**
         * @dev Returns the number of accounts that have `role`. Can be used
         * together with {getRoleMember} to enumerate all bearers of a role.
         */
        function getRoleMemberCount(bytes32 role) public view virtual override returns (uint256) {
            return _roleMembers[role].length();
        }
        /**
         * @dev Overload {_grantRole} to track enumerable memberships
         */
        function _grantRole(bytes32 role, address account) internal virtual override {
            super._grantRole(role, account);
            _roleMembers[role].add(account);
        }
        /**
         * @dev Overload {_revokeRole} to track enumerable memberships
         */
        function _revokeRole(bytes32 role, address account) internal virtual override {
            super._revokeRole(role, account);
            _roleMembers[role].remove(account);
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/extensions/ERC20Permit.sol)
    pragma solidity ^0.8.0;
    import "./IERC20PermitUpgradeable.sol";
    import "../ERC20Upgradeable.sol";
    import "../../../utils/cryptography/ECDSAUpgradeable.sol";
    import "../../../utils/cryptography/EIP712Upgradeable.sol";
    import "../../../utils/CountersUpgradeable.sol";
    import "../../../proxy/utils/Initializable.sol";
    /**
     * @dev Implementation of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
     * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
     *
     * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
     * presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't
     * need to send a transaction, and thus is not required to hold Ether at all.
     *
     * _Available since v3.4._
     *
     * @custom:storage-size 51
     */
    abstract contract ERC20PermitUpgradeable is Initializable, ERC20Upgradeable, IERC20PermitUpgradeable, EIP712Upgradeable {
        using CountersUpgradeable for CountersUpgradeable.Counter;
        mapping(address => CountersUpgradeable.Counter) private _nonces;
        // solhint-disable-next-line var-name-mixedcase
        bytes32 private constant _PERMIT_TYPEHASH =
            keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
        /**
         * @dev In previous versions `_PERMIT_TYPEHASH` was declared as `immutable`.
         * However, to ensure consistency with the upgradeable transpiler, we will continue
         * to reserve a slot.
         * @custom:oz-renamed-from _PERMIT_TYPEHASH
         */
        // solhint-disable-next-line var-name-mixedcase
        bytes32 private _PERMIT_TYPEHASH_DEPRECATED_SLOT;
        /**
         * @dev Initializes the {EIP712} domain separator using the `name` parameter, and setting `version` to `"1"`.
         *
         * It's a good idea to use the same `name` that is defined as the ERC20 token name.
         */
        function __ERC20Permit_init(string memory name) internal onlyInitializing {
            __EIP712_init_unchained(name, "1");
        }
        function __ERC20Permit_init_unchained(string memory) internal onlyInitializing {}
        /**
         * @dev See {IERC20Permit-permit}.
         */
        function permit(
            address owner,
            address spender,
            uint256 value,
            uint256 deadline,
            uint8 v,
            bytes32 r,
            bytes32 s
        ) public virtual override {
            require(block.timestamp <= deadline, "ERC20Permit: expired deadline");
            bytes32 structHash = keccak256(abi.encode(_PERMIT_TYPEHASH, owner, spender, value, _useNonce(owner), deadline));
            bytes32 hash = _hashTypedDataV4(structHash);
            address signer = ECDSAUpgradeable.recover(hash, v, r, s);
            require(signer == owner, "ERC20Permit: invalid signature");
            _approve(owner, spender, value);
        }
        /**
         * @dev See {IERC20Permit-nonces}.
         */
        function nonces(address owner) public view virtual override returns (uint256) {
            return _nonces[owner].current();
        }
        /**
         * @dev See {IERC20Permit-DOMAIN_SEPARATOR}.
         */
        // solhint-disable-next-line func-name-mixedcase
        function DOMAIN_SEPARATOR() external view override returns (bytes32) {
            return _domainSeparatorV4();
        }
        /**
         * @dev "Consume a nonce": return the current value and increment.
         *
         * _Available since v4.1._
         */
        function _useNonce(address owner) internal virtual returns (uint256 current) {
            CountersUpgradeable.Counter storage nonce = _nonces[owner];
            current = nonce.current();
            nonce.increment();
        }
        /**
         * @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
    pragma solidity ^0.8.20;
    import {IERC20Upgradeable} from "openzeppelin-upgradeable/token/ERC20/ERC20Upgradeable.sol";
    import {IERC20PermitUpgradeable} from "openzeppelin-upgradeable/token/ERC20/extensions/IERC20PermitUpgradeable.sol";
    interface IMETH is IERC20Upgradeable, IERC20PermitUpgradeable {
        /// @notice Mint mETH to the staker.
        /// @param staker The address of the staker.
        /// @param amount The amount of tokens to mint.
        function mint(address staker, uint256 amount) external;
        /// @notice Burn mETH from the msg.sender.
        /// @param amount The amount of tokens to burn.
        function burn(uint256 amount) external;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.20;
    interface IStakingInitiationRead {
        /// @notice The total amount of ETH sent to the beacon chain deposit contract.
        function totalDepositedInValidators() external view returns (uint256);
        /// @notice The number of validators initiated by the staking contract.
        function numInitiatedValidators() external view returns (uint256);
        /// @notice The block number at which the staking contract has been initialised.
        function initializationBlockNumber() external view returns (uint256);
    }
    interface IStakingReturnsWrite {
        /// @notice Accepts funds sent by the returns aggregator.
        function receiveReturns() external payable;
        /// @notice Accepts funds sent by the unstake requests manager.
        function receiveFromUnstakeRequestsManager() external payable;
    }
    interface IStaking is IStakingInitiationRead, IStakingReturnsWrite {}
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.20;
    import {Staking} from "../Staking.sol";
    /// @notice An unstake request is stored in the UnstakeRequestsManager and records the information required to
    /// fulfill an unstake request claim.
    /// @param id The unique ID of the unstake request.
    /// @param requester The address of the user that requested the unstake.
    /// @param mETHLocked The amount of mETH that was locked when the unstake request was created. The amount of mETH
    /// will be burned once the request has been claimed.
    /// @param ethRequested The amount of ETH that was requested when the unstake request was created.
    /// @param cumulativeETHRequested The cumulative amount of ETH that had been requested in this request and all unstake
    /// requests before this one.
    /// @param blockNumber The block number at which the unstake request was created.
    struct UnstakeRequest {
        uint64 blockNumber;
        address requester;
        uint128 id;
        uint128 mETHLocked;
        uint128 ethRequested;
        uint128 cumulativeETHRequested;
    }
    interface IUnstakeRequestsManagerWrite {
        /// @notice Creates a new unstake request and adds it to the unstake requests array.
        /// @param requester The address of the entity making the unstake request.
        /// @param mETHLocked The amount of mETH tokens currently locked in the contract.
        /// @param ethRequested The amount of ETH being requested for unstake.
        /// @return The ID of the new unstake request.
        function create(address requester, uint128 mETHLocked, uint128 ethRequested) external returns (uint256);
        /// @notice Allows the requester to claim their unstake request after it has been finalized.
        /// @param requestID The ID of the unstake request to claim.
        /// @param requester The address of the entity claiming the unstake request.
        function claim(uint256 requestID, address requester) external;
        /// @notice Cancels a batch of the latest unfinalized unstake requests.
        /// @param maxCancel The maximum number of requests to cancel.
        /// @return A boolean indicating if there are more unstake requests to cancel.
        function cancelUnfinalizedRequests(uint256 maxCancel) external returns (bool);
        /// @notice Allocate ether into the contract.
        function allocateETH() external payable;
        /// @notice Withdraws surplus ETH from the allocatedETHForClaims.
        function withdrawAllocatedETHSurplus() external;
    }
    interface IUnstakeRequestsManagerRead {
        /// @notice Retrieves a specific unstake request based on its ID.
        /// @param requestID The ID of the unstake request to fetch.
        /// @return The UnstakeRequest struct corresponding to the given ID.
        function requestByID(uint256 requestID) external view returns (UnstakeRequest memory);
        /// @notice Returns the status of the request whether it is finalized and how much ETH that has been filled.
        /// @param requestID The ID of the unstake request.
        /// @return bool indicating if the request is finalized, and the amount of ETH that has been filled.
        function requestInfo(uint256 requestID) external view returns (bool, uint256);
        /// @notice Calculates the amount of ether allocated in the contract exceeding the total required to pay unclaimed.
        /// @return The amount of surplus allocatedETH.
        function allocatedETHSurplus() external view returns (uint256);
        /// @notice Calculates the amount of ether that is needed to fulfill the unstake requests.
        /// @return The amount of allocatedETH deficit.
        function allocatedETHDeficit() external view returns (uint256);
        /// @notice Calculates the amount of ether that has been allocated but not yet claimed.
        /// @return The total amount of ether that is waiting to be claimed.
        function balance() external view returns (uint256);
    }
    interface IUnstakeRequestsManager is IUnstakeRequestsManagerRead, IUnstakeRequestsManagerWrite {}
    // 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 (access/IAccessControlEnumerable.sol)
    pragma solidity ^0.8.0;
    import "./IAccessControlUpgradeable.sol";
    /**
     * @dev External interface of AccessControlEnumerable declared to support ERC165 detection.
     */
    interface IAccessControlEnumerableUpgradeable is IAccessControlUpgradeable {
        /**
         * @dev Returns one of the accounts that have `role`. `index` must be a
         * value between 0 and {getRoleMemberCount}, non-inclusive.
         *
         * Role bearers are not sorted in any particular way, and their ordering may
         * change at any point.
         *
         * WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure
         * you perform all queries on the same block. See the following
         * https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296[forum post]
         * for more information.
         */
        function getRoleMember(bytes32 role, uint256 index) external view returns (address);
        /**
         * @dev Returns the number of accounts that have `role`. Can be used
         * together with {getRoleMember} to enumerate all bearers of a role.
         */
        function getRoleMemberCount(bytes32 role) external view returns (uint256);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.9.0) (access/AccessControl.sol)
    pragma solidity ^0.8.0;
    import "./IAccessControlUpgradeable.sol";
    import "../utils/ContextUpgradeable.sol";
    import "../utils/StringsUpgradeable.sol";
    import "../utils/introspection/ERC165Upgradeable.sol";
    import "../proxy/utils/Initializable.sol";
    /**
     * @dev Contract module that allows children to implement role-based access
     * control mechanisms. This is a lightweight version that doesn't allow enumerating role
     * members except through off-chain means by accessing the contract event logs. Some
     * applications may benefit from on-chain enumerability, for those cases see
     * {AccessControlEnumerable}.
     *
     * Roles are referred to by their `bytes32` identifier. These should be exposed
     * in the external API and be unique. The best way to achieve this is by
     * using `public constant` hash digests:
     *
     * ```solidity
     * bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
     * ```
     *
     * Roles can be used to represent a set of permissions. To restrict access to a
     * function call, use {hasRole}:
     *
     * ```solidity
     * function foo() public {
     *     require(hasRole(MY_ROLE, msg.sender));
     *     ...
     * }
     * ```
     *
     * Roles can be granted and revoked dynamically via the {grantRole} and
     * {revokeRole} functions. Each role has an associated admin role, and only
     * accounts that have a role's admin role can call {grantRole} and {revokeRole}.
     *
     * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
     * that only accounts with this role will be able to grant or revoke other
     * roles. More complex role relationships can be created by using
     * {_setRoleAdmin}.
     *
     * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
     * grant and revoke this role. Extra precautions should be taken to secure
     * accounts that have been granted it. We recommend using {AccessControlDefaultAdminRules}
     * to enforce additional security measures for this role.
     */
    abstract contract AccessControlUpgradeable is Initializable, ContextUpgradeable, IAccessControlUpgradeable, ERC165Upgradeable {
        function __AccessControl_init() internal onlyInitializing {
        }
        function __AccessControl_init_unchained() internal onlyInitializing {
        }
        struct RoleData {
            mapping(address => bool) members;
            bytes32 adminRole;
        }
        mapping(bytes32 => RoleData) private _roles;
        bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;
        /**
         * @dev Modifier that checks that an account has a specific role. Reverts
         * with a standardized message including the required role.
         *
         * The format of the revert reason is given by the following regular expression:
         *
         *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
         *
         * _Available since v4.1._
         */
        modifier onlyRole(bytes32 role) {
            _checkRole(role);
            _;
        }
        /**
         * @dev See {IERC165-supportsInterface}.
         */
        function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
            return interfaceId == type(IAccessControlUpgradeable).interfaceId || super.supportsInterface(interfaceId);
        }
        /**
         * @dev Returns `true` if `account` has been granted `role`.
         */
        function hasRole(bytes32 role, address account) public view virtual override returns (bool) {
            return _roles[role].members[account];
        }
        /**
         * @dev Revert with a standard message if `_msgSender()` is missing `role`.
         * Overriding this function changes the behavior of the {onlyRole} modifier.
         *
         * Format of the revert message is described in {_checkRole}.
         *
         * _Available since v4.6._
         */
        function _checkRole(bytes32 role) internal view virtual {
            _checkRole(role, _msgSender());
        }
        /**
         * @dev Revert with a standard message if `account` is missing `role`.
         *
         * The format of the revert reason is given by the following regular expression:
         *
         *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
         */
        function _checkRole(bytes32 role, address account) internal view virtual {
            if (!hasRole(role, account)) {
                revert(
                    string(
                        abi.encodePacked(
                            "AccessControl: account ",
                            StringsUpgradeable.toHexString(account),
                            " is missing role ",
                            StringsUpgradeable.toHexString(uint256(role), 32)
                        )
                    )
                );
            }
        }
        /**
         * @dev Returns the admin role that controls `role`. See {grantRole} and
         * {revokeRole}.
         *
         * To change a role's admin, use {_setRoleAdmin}.
         */
        function getRoleAdmin(bytes32 role) public view virtual override returns (bytes32) {
            return _roles[role].adminRole;
        }
        /**
         * @dev Grants `role` to `account`.
         *
         * If `account` had not been already granted `role`, emits a {RoleGranted}
         * event.
         *
         * Requirements:
         *
         * - the caller must have ``role``'s admin role.
         *
         * May emit a {RoleGranted} event.
         */
        function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
            _grantRole(role, account);
        }
        /**
         * @dev Revokes `role` from `account`.
         *
         * If `account` had been granted `role`, emits a {RoleRevoked} event.
         *
         * Requirements:
         *
         * - the caller must have ``role``'s admin role.
         *
         * May emit a {RoleRevoked} event.
         */
        function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
            _revokeRole(role, account);
        }
        /**
         * @dev Revokes `role` from the calling account.
         *
         * Roles are often managed via {grantRole} and {revokeRole}: this function's
         * purpose is to provide a mechanism for accounts to lose their privileges
         * if they are compromised (such as when a trusted device is misplaced).
         *
         * If the calling account had been revoked `role`, emits a {RoleRevoked}
         * event.
         *
         * Requirements:
         *
         * - the caller must be `account`.
         *
         * May emit a {RoleRevoked} event.
         */
        function renounceRole(bytes32 role, address account) public virtual override {
            require(account == _msgSender(), "AccessControl: can only renounce roles for self");
            _revokeRole(role, account);
        }
        /**
         * @dev Grants `role` to `account`.
         *
         * If `account` had not been already granted `role`, emits a {RoleGranted}
         * event. Note that unlike {grantRole}, this function doesn't perform any
         * checks on the calling account.
         *
         * May emit a {RoleGranted} event.
         *
         * [WARNING]
         * ====
         * This function should only be called from the constructor when setting
         * up the initial roles for the system.
         *
         * Using this function in any other way is effectively circumventing the admin
         * system imposed by {AccessControl}.
         * ====
         *
         * NOTE: This function is deprecated in favor of {_grantRole}.
         */
        function _setupRole(bytes32 role, address account) internal virtual {
            _grantRole(role, account);
        }
        /**
         * @dev Sets `adminRole` as ``role``'s admin role.
         *
         * Emits a {RoleAdminChanged} event.
         */
        function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
            bytes32 previousAdminRole = getRoleAdmin(role);
            _roles[role].adminRole = adminRole;
            emit RoleAdminChanged(role, previousAdminRole, adminRole);
        }
        /**
         * @dev Grants `role` to `account`.
         *
         * Internal function without access restriction.
         *
         * May emit a {RoleGranted} event.
         */
        function _grantRole(bytes32 role, address account) internal virtual {
            if (!hasRole(role, account)) {
                _roles[role].members[account] = true;
                emit RoleGranted(role, account, _msgSender());
            }
        }
        /**
         * @dev Revokes `role` from `account`.
         *
         * Internal function without access restriction.
         *
         * May emit a {RoleRevoked} event.
         */
        function _revokeRole(bytes32 role, address account) internal virtual {
            if (hasRole(role, account)) {
                _roles[role].members[account] = false;
                emit RoleRevoked(role, account, _msgSender());
            }
        }
        /**
         * @dev This empty reserved space is put in place to allow future versions to add new
         * variables without shifting down storage in the inheritance chain.
         * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
         */
        uint256[49] private __gap;
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.9.0) (utils/structs/EnumerableSet.sol)
    // This file was procedurally generated from scripts/generate/templates/EnumerableSet.js.
    pragma solidity ^0.8.0;
    /**
     * @dev Library for managing
     * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
     * types.
     *
     * Sets have the following properties:
     *
     * - Elements are added, removed, and checked for existence in constant time
     * (O(1)).
     * - Elements are enumerated in O(n). No guarantees are made on the ordering.
     *
     * ```solidity
     * contract Example {
     *     // Add the library methods
     *     using EnumerableSet for EnumerableSet.AddressSet;
     *
     *     // Declare a set state variable
     *     EnumerableSet.AddressSet private mySet;
     * }
     * ```
     *
     * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
     * and `uint256` (`UintSet`) are supported.
     *
     * [WARNING]
     * ====
     * Trying to delete such a structure from storage will likely result in data corruption, rendering the structure
     * unusable.
     * See https://github.com/ethereum/solidity/pull/11843[ethereum/solidity#11843] for more info.
     *
     * In order to clean an EnumerableSet, you can either remove all elements one by one or create a fresh instance using an
     * array of EnumerableSet.
     * ====
     */
    library EnumerableSetUpgradeable {
        // To implement this library for multiple types with as little code
        // repetition as possible, we write it in terms of a generic Set type with
        // bytes32 values.
        // The Set implementation uses private functions, and user-facing
        // implementations (such as AddressSet) are just wrappers around the
        // underlying Set.
        // This means that we can only create new EnumerableSets for types that fit
        // in bytes32.
        struct Set {
            // Storage of set values
            bytes32[] _values;
            // Position of the value in the `values` array, plus 1 because index 0
            // means a value is not in the set.
            mapping(bytes32 => uint256) _indexes;
        }
        /**
         * @dev Add a value to a set. O(1).
         *
         * Returns true if the value was added to the set, that is if it was not
         * already present.
         */
        function _add(Set storage set, bytes32 value) private returns (bool) {
            if (!_contains(set, value)) {
                set._values.push(value);
                // The value is stored at length-1, but we add 1 to all indexes
                // and use 0 as a sentinel value
                set._indexes[value] = set._values.length;
                return true;
            } else {
                return false;
            }
        }
        /**
         * @dev Removes a value from a set. O(1).
         *
         * Returns true if the value was removed from the set, that is if it was
         * present.
         */
        function _remove(Set storage set, bytes32 value) private returns (bool) {
            // We read and store the value's index to prevent multiple reads from the same storage slot
            uint256 valueIndex = set._indexes[value];
            if (valueIndex != 0) {
                // Equivalent to contains(set, value)
                // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
                // the array, and then remove the last element (sometimes called as 'swap and pop').
                // This modifies the order of the array, as noted in {at}.
                uint256 toDeleteIndex = valueIndex - 1;
                uint256 lastIndex = set._values.length - 1;
                if (lastIndex != toDeleteIndex) {
                    bytes32 lastValue = set._values[lastIndex];
                    // Move the last value to the index where the value to delete is
                    set._values[toDeleteIndex] = lastValue;
                    // Update the index for the moved value
                    set._indexes[lastValue] = valueIndex; // Replace lastValue's index to valueIndex
                }
                // Delete the slot where the moved value was stored
                set._values.pop();
                // Delete the index for the deleted slot
                delete set._indexes[value];
                return true;
            } else {
                return false;
            }
        }
        /**
         * @dev Returns true if the value is in the set. O(1).
         */
        function _contains(Set storage set, bytes32 value) private view returns (bool) {
            return set._indexes[value] != 0;
        }
        /**
         * @dev Returns the number of values on the set. O(1).
         */
        function _length(Set storage set) private view returns (uint256) {
            return set._values.length;
        }
        /**
         * @dev Returns the value stored at position `index` in the set. O(1).
         *
         * Note that there are no guarantees on the ordering of values inside the
         * array, and it may change when more values are added or removed.
         *
         * Requirements:
         *
         * - `index` must be strictly less than {length}.
         */
        function _at(Set storage set, uint256 index) private view returns (bytes32) {
            return set._values[index];
        }
        /**
         * @dev Return the entire set in an array
         *
         * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
         * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
         * this function has an unbounded cost, and using it as part of a state-changing function may render the function
         * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
         */
        function _values(Set storage set) private view returns (bytes32[] memory) {
            return set._values;
        }
        // Bytes32Set
        struct Bytes32Set {
            Set _inner;
        }
        /**
         * @dev Add a value to a set. O(1).
         *
         * Returns true if the value was added to the set, that is if it was not
         * already present.
         */
        function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
            return _add(set._inner, value);
        }
        /**
         * @dev Removes a value from a set. O(1).
         *
         * Returns true if the value was removed from the set, that is if it was
         * present.
         */
        function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
            return _remove(set._inner, value);
        }
        /**
         * @dev Returns true if the value is in the set. O(1).
         */
        function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
            return _contains(set._inner, value);
        }
        /**
         * @dev Returns the number of values in the set. O(1).
         */
        function length(Bytes32Set storage set) internal view returns (uint256) {
            return _length(set._inner);
        }
        /**
         * @dev Returns the value stored at position `index` in the set. O(1).
         *
         * Note that there are no guarantees on the ordering of values inside the
         * array, and it may change when more values are added or removed.
         *
         * Requirements:
         *
         * - `index` must be strictly less than {length}.
         */
        function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
            return _at(set._inner, index);
        }
        /**
         * @dev Return the entire set in an array
         *
         * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
         * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
         * this function has an unbounded cost, and using it as part of a state-changing function may render the function
         * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
         */
        function values(Bytes32Set storage set) internal view returns (bytes32[] memory) {
            bytes32[] memory store = _values(set._inner);
            bytes32[] memory result;
            /// @solidity memory-safe-assembly
            assembly {
                result := store
            }
            return result;
        }
        // AddressSet
        struct AddressSet {
            Set _inner;
        }
        /**
         * @dev Add a value to a set. O(1).
         *
         * Returns true if the value was added to the set, that is if it was not
         * already present.
         */
        function add(AddressSet storage set, address value) internal returns (bool) {
            return _add(set._inner, bytes32(uint256(uint160(value))));
        }
        /**
         * @dev Removes a value from a set. O(1).
         *
         * Returns true if the value was removed from the set, that is if it was
         * present.
         */
        function remove(AddressSet storage set, address value) internal returns (bool) {
            return _remove(set._inner, bytes32(uint256(uint160(value))));
        }
        /**
         * @dev Returns true if the value is in the set. O(1).
         */
        function contains(AddressSet storage set, address value) internal view returns (bool) {
            return _contains(set._inner, bytes32(uint256(uint160(value))));
        }
        /**
         * @dev Returns the number of values in the set. O(1).
         */
        function length(AddressSet storage set) internal view returns (uint256) {
            return _length(set._inner);
        }
        /**
         * @dev Returns the value stored at position `index` in the set. O(1).
         *
         * Note that there are no guarantees on the ordering of values inside the
         * array, and it may change when more values are added or removed.
         *
         * Requirements:
         *
         * - `index` must be strictly less than {length}.
         */
        function at(AddressSet storage set, uint256 index) internal view returns (address) {
            return address(uint160(uint256(_at(set._inner, index))));
        }
        /**
         * @dev Return the entire set in an array
         *
         * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
         * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
         * this function has an unbounded cost, and using it as part of a state-changing function may render the function
         * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
         */
        function values(AddressSet storage set) internal view returns (address[] memory) {
            bytes32[] memory store = _values(set._inner);
            address[] memory result;
            /// @solidity memory-safe-assembly
            assembly {
                result := store
            }
            return result;
        }
        // UintSet
        struct UintSet {
            Set _inner;
        }
        /**
         * @dev Add a value to a set. O(1).
         *
         * Returns true if the value was added to the set, that is if it was not
         * already present.
         */
        function add(UintSet storage set, uint256 value) internal returns (bool) {
            return _add(set._inner, bytes32(value));
        }
        /**
         * @dev Removes a value from a set. O(1).
         *
         * Returns true if the value was removed from the set, that is if it was
         * present.
         */
        function remove(UintSet storage set, uint256 value) internal returns (bool) {
            return _remove(set._inner, bytes32(value));
        }
        /**
         * @dev Returns true if the value is in the set. O(1).
         */
        function contains(UintSet storage set, uint256 value) internal view returns (bool) {
            return _contains(set._inner, bytes32(value));
        }
        /**
         * @dev Returns the number of values in the set. O(1).
         */
        function length(UintSet storage set) internal view returns (uint256) {
            return _length(set._inner);
        }
        /**
         * @dev Returns the value stored at position `index` in the set. O(1).
         *
         * Note that there are no guarantees on the ordering of values inside the
         * array, and it may change when more values are added or removed.
         *
         * Requirements:
         *
         * - `index` must be strictly less than {length}.
         */
        function at(UintSet storage set, uint256 index) internal view returns (uint256) {
            return uint256(_at(set._inner, index));
        }
        /**
         * @dev Return the entire set in an array
         *
         * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
         * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
         * this function has an unbounded cost, and using it as part of a state-changing function may render the function
         * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
         */
        function values(UintSet storage set) internal view returns (uint256[] memory) {
            bytes32[] memory store = _values(set._inner);
            uint256[] memory result;
            /// @solidity memory-safe-assembly
            assembly {
                result := store
            }
            return result;
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts v4.4.1 (access/IAccessControlEnumerable.sol)
    pragma solidity ^0.8.0;
    import "./IAccessControl.sol";
    /**
     * @dev External interface of AccessControlEnumerable declared to support ERC165 detection.
     */
    interface IAccessControlEnumerable is IAccessControl {
        /**
         * @dev Returns one of the accounts that have `role`. `index` must be a
         * value between 0 and {getRoleMemberCount}, non-inclusive.
         *
         * Role bearers are not sorted in any particular way, and their ordering may
         * change at any point.
         *
         * WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure
         * you perform all queries on the same block. See the following
         * https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296[forum post]
         * for more information.
         */
        function getRoleMember(bytes32 role, uint256 index) external view returns (address);
        /**
         * @dev Returns the number of accounts that have `role`. Can be used
         * together with {getRoleMember} to enumerate all bearers of a role.
         */
        function getRoleMemberCount(bytes32 role) external view returns (uint256);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.8.0) (access/AccessControl.sol)
    pragma solidity ^0.8.0;
    import "./IAccessControl.sol";
    import "../utils/Context.sol";
    import "../utils/Strings.sol";
    import "../utils/introspection/ERC165.sol";
    /**
     * @dev Contract module that allows children to implement role-based access
     * control mechanisms. This is a lightweight version that doesn't allow enumerating role
     * members except through off-chain means by accessing the contract event logs. Some
     * applications may benefit from on-chain enumerability, for those cases see
     * {AccessControlEnumerable}.
     *
     * Roles are referred to by their `bytes32` identifier. These should be exposed
     * in the external API and be unique. The best way to achieve this is by
     * using `public constant` hash digests:
     *
     * ```solidity
     * bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
     * ```
     *
     * Roles can be used to represent a set of permissions. To restrict access to a
     * function call, use {hasRole}:
     *
     * ```solidity
     * function foo() public {
     *     require(hasRole(MY_ROLE, msg.sender));
     *     ...
     * }
     * ```
     *
     * Roles can be granted and revoked dynamically via the {grantRole} and
     * {revokeRole} functions. Each role has an associated admin role, and only
     * accounts that have a role's admin role can call {grantRole} and {revokeRole}.
     *
     * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
     * that only accounts with this role will be able to grant or revoke other
     * roles. More complex role relationships can be created by using
     * {_setRoleAdmin}.
     *
     * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
     * grant and revoke this role. Extra precautions should be taken to secure
     * accounts that have been granted it. We recommend using {AccessControlDefaultAdminRules}
     * to enforce additional security measures for this role.
     */
    abstract contract AccessControl is Context, IAccessControl, ERC165 {
        struct RoleData {
            mapping(address => bool) members;
            bytes32 adminRole;
        }
        mapping(bytes32 => RoleData) private _roles;
        bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;
        /**
         * @dev Modifier that checks that an account has a specific role. Reverts
         * with a standardized message including the required role.
         *
         * The format of the revert reason is given by the following regular expression:
         *
         *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
         *
         * _Available since v4.1._
         */
        modifier onlyRole(bytes32 role) {
            _checkRole(role);
            _;
        }
        /**
         * @dev See {IERC165-supportsInterface}.
         */
        function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
            return interfaceId == type(IAccessControl).interfaceId || super.supportsInterface(interfaceId);
        }
        /**
         * @dev Returns `true` if `account` has been granted `role`.
         */
        function hasRole(bytes32 role, address account) public view virtual override returns (bool) {
            return _roles[role].members[account];
        }
        /**
         * @dev Revert with a standard message if `_msgSender()` is missing `role`.
         * Overriding this function changes the behavior of the {onlyRole} modifier.
         *
         * Format of the revert message is described in {_checkRole}.
         *
         * _Available since v4.6._
         */
        function _checkRole(bytes32 role) internal view virtual {
            _checkRole(role, _msgSender());
        }
        /**
         * @dev Revert with a standard message if `account` is missing `role`.
         *
         * The format of the revert reason is given by the following regular expression:
         *
         *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
         */
        function _checkRole(bytes32 role, address account) internal view virtual {
            if (!hasRole(role, account)) {
                revert(
                    string(
                        abi.encodePacked(
                            "AccessControl: account ",
                            Strings.toHexString(account),
                            " is missing role ",
                            Strings.toHexString(uint256(role), 32)
                        )
                    )
                );
            }
        }
        /**
         * @dev Returns the admin role that controls `role`. See {grantRole} and
         * {revokeRole}.
         *
         * To change a role's admin, use {_setRoleAdmin}.
         */
        function getRoleAdmin(bytes32 role) public view virtual override returns (bytes32) {
            return _roles[role].adminRole;
        }
        /**
         * @dev Grants `role` to `account`.
         *
         * If `account` had not been already granted `role`, emits a {RoleGranted}
         * event.
         *
         * Requirements:
         *
         * - the caller must have ``role``'s admin role.
         *
         * May emit a {RoleGranted} event.
         */
        function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
            _grantRole(role, account);
        }
        /**
         * @dev Revokes `role` from `account`.
         *
         * If `account` had been granted `role`, emits a {RoleRevoked} event.
         *
         * Requirements:
         *
         * - the caller must have ``role``'s admin role.
         *
         * May emit a {RoleRevoked} event.
         */
        function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
            _revokeRole(role, account);
        }
        /**
         * @dev Revokes `role` from the calling account.
         *
         * Roles are often managed via {grantRole} and {revokeRole}: this function's
         * purpose is to provide a mechanism for accounts to lose their privileges
         * if they are compromised (such as when a trusted device is misplaced).
         *
         * If the calling account had been revoked `role`, emits a {RoleRevoked}
         * event.
         *
         * Requirements:
         *
         * - the caller must be `account`.
         *
         * May emit a {RoleRevoked} event.
         */
        function renounceRole(bytes32 role, address account) public virtual override {
            require(account == _msgSender(), "AccessControl: can only renounce roles for self");
            _revokeRole(role, account);
        }
        /**
         * @dev Grants `role` to `account`.
         *
         * If `account` had not been already granted `role`, emits a {RoleGranted}
         * event. Note that unlike {grantRole}, this function doesn't perform any
         * checks on the calling account.
         *
         * May emit a {RoleGranted} event.
         *
         * [WARNING]
         * ====
         * This function should only be called from the constructor when setting
         * up the initial roles for the system.
         *
         * Using this function in any other way is effectively circumventing the admin
         * system imposed by {AccessControl}.
         * ====
         *
         * NOTE: This function is deprecated in favor of {_grantRole}.
         */
        function _setupRole(bytes32 role, address account) internal virtual {
            _grantRole(role, account);
        }
        /**
         * @dev Sets `adminRole` as ``role``'s admin role.
         *
         * Emits a {RoleAdminChanged} event.
         */
        function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
            bytes32 previousAdminRole = getRoleAdmin(role);
            _roles[role].adminRole = adminRole;
            emit RoleAdminChanged(role, previousAdminRole, adminRole);
        }
        /**
         * @dev Grants `role` to `account`.
         *
         * Internal function without access restriction.
         *
         * May emit a {RoleGranted} event.
         */
        function _grantRole(bytes32 role, address account) internal virtual {
            if (!hasRole(role, account)) {
                _roles[role].members[account] = true;
                emit RoleGranted(role, account, _msgSender());
            }
        }
        /**
         * @dev Revokes `role` from `account`.
         *
         * Internal function without access restriction.
         *
         * May emit a {RoleRevoked} event.
         */
        function _revokeRole(bytes32 role, address account) internal virtual {
            if (hasRole(role, account)) {
                _roles[role].members[account] = false;
                emit RoleRevoked(role, account, _msgSender());
            }
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.8.0) (utils/structs/EnumerableSet.sol)
    // This file was procedurally generated from scripts/generate/templates/EnumerableSet.js.
    pragma solidity ^0.8.0;
    /**
     * @dev Library for managing
     * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
     * types.
     *
     * Sets have the following properties:
     *
     * - Elements are added, removed, and checked for existence in constant time
     * (O(1)).
     * - Elements are enumerated in O(n). No guarantees are made on the ordering.
     *
     * ```solidity
     * contract Example {
     *     // Add the library methods
     *     using EnumerableSet for EnumerableSet.AddressSet;
     *
     *     // Declare a set state variable
     *     EnumerableSet.AddressSet private mySet;
     * }
     * ```
     *
     * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
     * and `uint256` (`UintSet`) are supported.
     *
     * [WARNING]
     * ====
     * Trying to delete such a structure from storage will likely result in data corruption, rendering the structure
     * unusable.
     * See https://github.com/ethereum/solidity/pull/11843[ethereum/solidity#11843] for more info.
     *
     * In order to clean an EnumerableSet, you can either remove all elements one by one or create a fresh instance using an
     * array of EnumerableSet.
     * ====
     */
    library EnumerableSet {
        // To implement this library for multiple types with as little code
        // repetition as possible, we write it in terms of a generic Set type with
        // bytes32 values.
        // The Set implementation uses private functions, and user-facing
        // implementations (such as AddressSet) are just wrappers around the
        // underlying Set.
        // This means that we can only create new EnumerableSets for types that fit
        // in bytes32.
        struct Set {
            // Storage of set values
            bytes32[] _values;
            // Position of the value in the `values` array, plus 1 because index 0
            // means a value is not in the set.
            mapping(bytes32 => uint256) _indexes;
        }
        /**
         * @dev Add a value to a set. O(1).
         *
         * Returns true if the value was added to the set, that is if it was not
         * already present.
         */
        function _add(Set storage set, bytes32 value) private returns (bool) {
            if (!_contains(set, value)) {
                set._values.push(value);
                // The value is stored at length-1, but we add 1 to all indexes
                // and use 0 as a sentinel value
                set._indexes[value] = set._values.length;
                return true;
            } else {
                return false;
            }
        }
        /**
         * @dev Removes a value from a set. O(1).
         *
         * Returns true if the value was removed from the set, that is if it was
         * present.
         */
        function _remove(Set storage set, bytes32 value) private returns (bool) {
            // We read and store the value's index to prevent multiple reads from the same storage slot
            uint256 valueIndex = set._indexes[value];
            if (valueIndex != 0) {
                // Equivalent to contains(set, value)
                // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
                // the array, and then remove the last element (sometimes called as 'swap and pop').
                // This modifies the order of the array, as noted in {at}.
                uint256 toDeleteIndex = valueIndex - 1;
                uint256 lastIndex = set._values.length - 1;
                if (lastIndex != toDeleteIndex) {
                    bytes32 lastValue = set._values[lastIndex];
                    // Move the last value to the index where the value to delete is
                    set._values[toDeleteIndex] = lastValue;
                    // Update the index for the moved value
                    set._indexes[lastValue] = valueIndex; // Replace lastValue's index to valueIndex
                }
                // Delete the slot where the moved value was stored
                set._values.pop();
                // Delete the index for the deleted slot
                delete set._indexes[value];
                return true;
            } else {
                return false;
            }
        }
        /**
         * @dev Returns true if the value is in the set. O(1).
         */
        function _contains(Set storage set, bytes32 value) private view returns (bool) {
            return set._indexes[value] != 0;
        }
        /**
         * @dev Returns the number of values on the set. O(1).
         */
        function _length(Set storage set) private view returns (uint256) {
            return set._values.length;
        }
        /**
         * @dev Returns the value stored at position `index` in the set. O(1).
         *
         * Note that there are no guarantees on the ordering of values inside the
         * array, and it may change when more values are added or removed.
         *
         * Requirements:
         *
         * - `index` must be strictly less than {length}.
         */
        function _at(Set storage set, uint256 index) private view returns (bytes32) {
            return set._values[index];
        }
        /**
         * @dev Return the entire set in an array
         *
         * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
         * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
         * this function has an unbounded cost, and using it as part of a state-changing function may render the function
         * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
         */
        function _values(Set storage set) private view returns (bytes32[] memory) {
            return set._values;
        }
        // Bytes32Set
        struct Bytes32Set {
            Set _inner;
        }
        /**
         * @dev Add a value to a set. O(1).
         *
         * Returns true if the value was added to the set, that is if it was not
         * already present.
         */
        function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
            return _add(set._inner, value);
        }
        /**
         * @dev Removes a value from a set. O(1).
         *
         * Returns true if the value was removed from the set, that is if it was
         * present.
         */
        function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
            return _remove(set._inner, value);
        }
        /**
         * @dev Returns true if the value is in the set. O(1).
         */
        function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
            return _contains(set._inner, value);
        }
        /**
         * @dev Returns the number of values in the set. O(1).
         */
        function length(Bytes32Set storage set) internal view returns (uint256) {
            return _length(set._inner);
        }
        /**
         * @dev Returns the value stored at position `index` in the set. O(1).
         *
         * Note that there are no guarantees on the ordering of values inside the
         * array, and it may change when more values are added or removed.
         *
         * Requirements:
         *
         * - `index` must be strictly less than {length}.
         */
        function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
            return _at(set._inner, index);
        }
        /**
         * @dev Return the entire set in an array
         *
         * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
         * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
         * this function has an unbounded cost, and using it as part of a state-changing function may render the function
         * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
         */
        function values(Bytes32Set storage set) internal view returns (bytes32[] memory) {
            bytes32[] memory store = _values(set._inner);
            bytes32[] memory result;
            /// @solidity memory-safe-assembly
            assembly {
                result := store
            }
            return result;
        }
        // AddressSet
        struct AddressSet {
            Set _inner;
        }
        /**
         * @dev Add a value to a set. O(1).
         *
         * Returns true if the value was added to the set, that is if it was not
         * already present.
         */
        function add(AddressSet storage set, address value) internal returns (bool) {
            return _add(set._inner, bytes32(uint256(uint160(value))));
        }
        /**
         * @dev Removes a value from a set. O(1).
         *
         * Returns true if the value was removed from the set, that is if it was
         * present.
         */
        function remove(AddressSet storage set, address value) internal returns (bool) {
            return _remove(set._inner, bytes32(uint256(uint160(value))));
        }
        /**
         * @dev Returns true if the value is in the set. O(1).
         */
        function contains(AddressSet storage set, address value) internal view returns (bool) {
            return _contains(set._inner, bytes32(uint256(uint160(value))));
        }
        /**
         * @dev Returns the number of values in the set. O(1).
         */
        function length(AddressSet storage set) internal view returns (uint256) {
            return _length(set._inner);
        }
        /**
         * @dev Returns the value stored at position `index` in the set. O(1).
         *
         * Note that there are no guarantees on the ordering of values inside the
         * array, and it may change when more values are added or removed.
         *
         * Requirements:
         *
         * - `index` must be strictly less than {length}.
         */
        function at(AddressSet storage set, uint256 index) internal view returns (address) {
            return address(uint160(uint256(_at(set._inner, index))));
        }
        /**
         * @dev Return the entire set in an array
         *
         * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
         * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
         * this function has an unbounded cost, and using it as part of a state-changing function may render the function
         * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
         */
        function values(AddressSet storage set) internal view returns (address[] memory) {
            bytes32[] memory store = _values(set._inner);
            address[] memory result;
            /// @solidity memory-safe-assembly
            assembly {
                result := store
            }
            return result;
        }
        // UintSet
        struct UintSet {
            Set _inner;
        }
        /**
         * @dev Add a value to a set. O(1).
         *
         * Returns true if the value was added to the set, that is if it was not
         * already present.
         */
        function add(UintSet storage set, uint256 value) internal returns (bool) {
            return _add(set._inner, bytes32(value));
        }
        /**
         * @dev Removes a value from a set. O(1).
         *
         * Returns true if the value was removed from the set, that is if it was
         * present.
         */
        function remove(UintSet storage set, uint256 value) internal returns (bool) {
            return _remove(set._inner, bytes32(value));
        }
        /**
         * @dev Returns true if the value is in the set. O(1).
         */
        function contains(UintSet storage set, uint256 value) internal view returns (bool) {
            return _contains(set._inner, bytes32(value));
        }
        /**
         * @dev Returns the number of values in the set. O(1).
         */
        function length(UintSet storage set) internal view returns (uint256) {
            return _length(set._inner);
        }
        /**
         * @dev Returns the value stored at position `index` in the set. O(1).
         *
         * Note that there are no guarantees on the ordering of values inside the
         * array, and it may change when more values are added or removed.
         *
         * Requirements:
         *
         * - `index` must be strictly less than {length}.
         */
        function at(UintSet storage set, uint256 index) internal view returns (uint256) {
            return uint256(_at(set._inner, index));
        }
        /**
         * @dev Return the entire set in an array
         *
         * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
         * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
         * this function has an unbounded cost, and using it as part of a state-changing function may render the function
         * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
         */
        function values(UintSet storage set) internal view returns (uint256[] memory) {
            bytes32[] memory store = _values(set._inner);
            uint256[] memory result;
            /// @solidity memory-safe-assembly
            assembly {
                result := store
            }
            return result;
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/extensions/IERC20Permit.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
     * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
     *
     * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
     * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
     * need to send a transaction, and thus is not required to hold Ether at all.
     */
    interface IERC20PermitUpgradeable {
        /**
         * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
         * given ``owner``'s signed approval.
         *
         * IMPORTANT: The same issues {IERC20-approve} has related to transaction
         * ordering also apply here.
         *
         * Emits an {Approval} event.
         *
         * Requirements:
         *
         * - `spender` cannot be the zero address.
         * - `deadline` must be a timestamp in the future.
         * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
         * over the EIP712-formatted function arguments.
         * - the signature must use ``owner``'s current nonce (see {nonces}).
         *
         * For more information on the signature format, see the
         * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
         * section].
         */
        function permit(
            address owner,
            address spender,
            uint256 value,
            uint256 deadline,
            uint8 v,
            bytes32 r,
            bytes32 s
        ) external;
        /**
         * @dev Returns the current nonce for `owner`. This value must be
         * included whenever a signature is generated for {permit}.
         *
         * Every successful call to {permit} increases ``owner``'s nonce by one. This
         * prevents a signature from being used multiple times.
         */
        function nonces(address owner) external view returns (uint256);
        /**
         * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
         */
        // solhint-disable-next-line func-name-mixedcase
        function DOMAIN_SEPARATOR() external view returns (bytes32);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/ERC20.sol)
    pragma solidity ^0.8.0;
    import "./IERC20Upgradeable.sol";
    import "./extensions/IERC20MetadataUpgradeable.sol";
    import "../../utils/ContextUpgradeable.sol";
    import "../../proxy/utils/Initializable.sol";
    /**
     * @dev Implementation of the {IERC20} interface.
     *
     * This implementation is agnostic to the way tokens are created. This means
     * that a supply mechanism has to be added in a derived contract using {_mint}.
     * For a generic mechanism see {ERC20PresetMinterPauser}.
     *
     * TIP: For a detailed writeup see our guide
     * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
     * to implement supply mechanisms].
     *
     * The default value of {decimals} is 18. To change this, you should override
     * this function so it returns a different value.
     *
     * We have followed general OpenZeppelin Contracts guidelines: functions revert
     * instead returning `false` on failure. This behavior is nonetheless
     * conventional and does not conflict with the expectations of ERC20
     * applications.
     *
     * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
     * This allows applications to reconstruct the allowance for all accounts just
     * by listening to said events. Other implementations of the EIP may not emit
     * these events, as it isn't required by the specification.
     *
     * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
     * functions have been added to mitigate the well-known issues around setting
     * allowances. See {IERC20-approve}.
     */
    contract ERC20Upgradeable is Initializable, ContextUpgradeable, IERC20Upgradeable, IERC20MetadataUpgradeable {
        mapping(address => uint256) private _balances;
        mapping(address => mapping(address => uint256)) private _allowances;
        uint256 private _totalSupply;
        string private _name;
        string private _symbol;
        /**
         * @dev Sets the values for {name} and {symbol}.
         *
         * All two of these values are immutable: they can only be set once during
         * construction.
         */
        function __ERC20_init(string memory name_, string memory symbol_) internal onlyInitializing {
            __ERC20_init_unchained(name_, symbol_);
        }
        function __ERC20_init_unchained(string memory name_, string memory symbol_) internal onlyInitializing {
            _name = name_;
            _symbol = symbol_;
        }
        /**
         * @dev Returns the name of the token.
         */
        function name() public view virtual override returns (string memory) {
            return _name;
        }
        /**
         * @dev Returns the symbol of the token, usually a shorter version of the
         * name.
         */
        function symbol() public view virtual override returns (string memory) {
            return _symbol;
        }
        /**
         * @dev Returns the number of decimals used to get its user representation.
         * For example, if `decimals` equals `2`, a balance of `505` tokens should
         * be displayed to a user as `5.05` (`505 / 10 ** 2`).
         *
         * Tokens usually opt for a value of 18, imitating the relationship between
         * Ether and Wei. This is the default value returned by this function, unless
         * it's overridden.
         *
         * NOTE: This information is only used for _display_ purposes: it in
         * no way affects any of the arithmetic of the contract, including
         * {IERC20-balanceOf} and {IERC20-transfer}.
         */
        function decimals() public view virtual override returns (uint8) {
            return 18;
        }
        /**
         * @dev See {IERC20-totalSupply}.
         */
        function totalSupply() public view virtual override returns (uint256) {
            return _totalSupply;
        }
        /**
         * @dev See {IERC20-balanceOf}.
         */
        function balanceOf(address account) public view virtual override returns (uint256) {
            return _balances[account];
        }
        /**
         * @dev See {IERC20-transfer}.
         *
         * Requirements:
         *
         * - `to` cannot be the zero address.
         * - the caller must have a balance of at least `amount`.
         */
        function transfer(address to, uint256 amount) public virtual override returns (bool) {
            address owner = _msgSender();
            _transfer(owner, to, amount);
            return true;
        }
        /**
         * @dev See {IERC20-allowance}.
         */
        function allowance(address owner, address spender) public view virtual override returns (uint256) {
            return _allowances[owner][spender];
        }
        /**
         * @dev See {IERC20-approve}.
         *
         * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
         * `transferFrom`. This is semantically equivalent to an infinite approval.
         *
         * Requirements:
         *
         * - `spender` cannot be the zero address.
         */
        function approve(address spender, uint256 amount) public virtual override returns (bool) {
            address owner = _msgSender();
            _approve(owner, spender, amount);
            return true;
        }
        /**
         * @dev See {IERC20-transferFrom}.
         *
         * Emits an {Approval} event indicating the updated allowance. This is not
         * required by the EIP. See the note at the beginning of {ERC20}.
         *
         * NOTE: Does not update the allowance if the current allowance
         * is the maximum `uint256`.
         *
         * Requirements:
         *
         * - `from` and `to` cannot be the zero address.
         * - `from` must have a balance of at least `amount`.
         * - the caller must have allowance for ``from``'s tokens of at least
         * `amount`.
         */
        function transferFrom(address from, address to, uint256 amount) public virtual override returns (bool) {
            address spender = _msgSender();
            _spendAllowance(from, spender, amount);
            _transfer(from, to, amount);
            return true;
        }
        /**
         * @dev Atomically increases the allowance granted to `spender` by the caller.
         *
         * This is an alternative to {approve} that can be used as a mitigation for
         * problems described in {IERC20-approve}.
         *
         * Emits an {Approval} event indicating the updated allowance.
         *
         * Requirements:
         *
         * - `spender` cannot be the zero address.
         */
        function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
            address owner = _msgSender();
            _approve(owner, spender, allowance(owner, spender) + addedValue);
            return true;
        }
        /**
         * @dev Atomically decreases the allowance granted to `spender` by the caller.
         *
         * This is an alternative to {approve} that can be used as a mitigation for
         * problems described in {IERC20-approve}.
         *
         * Emits an {Approval} event indicating the updated allowance.
         *
         * Requirements:
         *
         * - `spender` cannot be the zero address.
         * - `spender` must have allowance for the caller of at least
         * `subtractedValue`.
         */
        function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
            address owner = _msgSender();
            uint256 currentAllowance = allowance(owner, spender);
            require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
            unchecked {
                _approve(owner, spender, currentAllowance - subtractedValue);
            }
            return true;
        }
        /**
         * @dev Moves `amount` of tokens from `from` to `to`.
         *
         * This internal function is equivalent to {transfer}, and can be used to
         * e.g. implement automatic token fees, slashing mechanisms, etc.
         *
         * Emits a {Transfer} event.
         *
         * Requirements:
         *
         * - `from` cannot be the zero address.
         * - `to` cannot be the zero address.
         * - `from` must have a balance of at least `amount`.
         */
        function _transfer(address from, address to, uint256 amount) internal virtual {
            require(from != address(0), "ERC20: transfer from the zero address");
            require(to != address(0), "ERC20: transfer to the zero address");
            _beforeTokenTransfer(from, to, amount);
            uint256 fromBalance = _balances[from];
            require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
            unchecked {
                _balances[from] = fromBalance - amount;
                // Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
                // decrementing then incrementing.
                _balances[to] += amount;
            }
            emit Transfer(from, to, amount);
            _afterTokenTransfer(from, to, amount);
        }
        /** @dev Creates `amount` tokens and assigns them to `account`, increasing
         * the total supply.
         *
         * Emits a {Transfer} event with `from` set to the zero address.
         *
         * Requirements:
         *
         * - `account` cannot be the zero address.
         */
        function _mint(address account, uint256 amount) internal virtual {
            require(account != address(0), "ERC20: mint to the zero address");
            _beforeTokenTransfer(address(0), account, amount);
            _totalSupply += amount;
            unchecked {
                // Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
                _balances[account] += amount;
            }
            emit Transfer(address(0), account, amount);
            _afterTokenTransfer(address(0), account, amount);
        }
        /**
         * @dev Destroys `amount` tokens from `account`, reducing the
         * total supply.
         *
         * Emits a {Transfer} event with `to` set to the zero address.
         *
         * Requirements:
         *
         * - `account` cannot be the zero address.
         * - `account` must have at least `amount` tokens.
         */
        function _burn(address account, uint256 amount) internal virtual {
            require(account != address(0), "ERC20: burn from the zero address");
            _beforeTokenTransfer(account, address(0), amount);
            uint256 accountBalance = _balances[account];
            require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
            unchecked {
                _balances[account] = accountBalance - amount;
                // Overflow not possible: amount <= accountBalance <= totalSupply.
                _totalSupply -= amount;
            }
            emit Transfer(account, address(0), amount);
            _afterTokenTransfer(account, address(0), amount);
        }
        /**
         * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
         *
         * This internal function is equivalent to `approve`, and can be used to
         * e.g. set automatic allowances for certain subsystems, etc.
         *
         * Emits an {Approval} event.
         *
         * Requirements:
         *
         * - `owner` cannot be the zero address.
         * - `spender` cannot be the zero address.
         */
        function _approve(address owner, address spender, uint256 amount) internal virtual {
            require(owner != address(0), "ERC20: approve from the zero address");
            require(spender != address(0), "ERC20: approve to the zero address");
            _allowances[owner][spender] = amount;
            emit Approval(owner, spender, amount);
        }
        /**
         * @dev Updates `owner` s allowance for `spender` based on spent `amount`.
         *
         * Does not update the allowance amount in case of infinite allowance.
         * Revert if not enough allowance is available.
         *
         * Might emit an {Approval} event.
         */
        function _spendAllowance(address owner, address spender, uint256 amount) internal virtual {
            uint256 currentAllowance = allowance(owner, spender);
            if (currentAllowance != type(uint256).max) {
                require(currentAllowance >= amount, "ERC20: insufficient allowance");
                unchecked {
                    _approve(owner, spender, currentAllowance - amount);
                }
            }
        }
        /**
         * @dev Hook that is called before any transfer of tokens. This includes
         * minting and burning.
         *
         * Calling conditions:
         *
         * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
         * will be transferred to `to`.
         * - when `from` is zero, `amount` tokens will be minted for `to`.
         * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
         * - `from` and `to` are never both zero.
         *
         * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
         */
        function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual {}
        /**
         * @dev Hook that is called after any transfer of tokens. This includes
         * minting and burning.
         *
         * Calling conditions:
         *
         * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
         * has been transferred to `to`.
         * - when `from` is zero, `amount` tokens have been minted for `to`.
         * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
         * - `from` and `to` are never both zero.
         *
         * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
         */
        function _afterTokenTransfer(address from, address to, uint256 amount) internal virtual {}
        /**
         * @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[45] private __gap;
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.9.0) (utils/cryptography/ECDSA.sol)
    pragma solidity ^0.8.0;
    import "../StringsUpgradeable.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 ECDSAUpgradeable {
        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:\
    32")
                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:\
    ", StringsUpgradeable.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 (last updated v4.9.0) (utils/cryptography/EIP712.sol)
    pragma solidity ^0.8.8;
    import "./ECDSAUpgradeable.sol";
    import "../../interfaces/IERC5267Upgradeable.sol";
    import "../../proxy/utils/Initializable.sol";
    /**
     * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
     *
     * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
     * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
     * they need in their contracts using a combination of `abi.encode` and `keccak256`.
     *
     * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
     * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
     * ({_hashTypedDataV4}).
     *
     * The implementation of the domain separator was designed to be as efficient as possible while still properly updating
     * the chain id to protect against replay attacks on an eventual fork of the chain.
     *
     * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
     * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
     *
     * NOTE: In the upgradeable version of this contract, the cached values will correspond to the address, and the domain
     * separator of the implementation contract. This will cause the `_domainSeparatorV4` function to always rebuild the
     * separator from the immutable values, which is cheaper than accessing a cached version in cold storage.
     *
     * _Available since v3.4._
     *
     * @custom:storage-size 52
     */
    abstract contract EIP712Upgradeable is Initializable, IERC5267Upgradeable {
        bytes32 private constant _TYPE_HASH =
            keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)");
        /// @custom:oz-renamed-from _HASHED_NAME
        bytes32 private _hashedName;
        /// @custom:oz-renamed-from _HASHED_VERSION
        bytes32 private _hashedVersion;
        string private _name;
        string private _version;
        /**
         * @dev Initializes the domain separator and parameter caches.
         *
         * The meaning of `name` and `version` is specified in
         * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
         *
         * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
         * - `version`: the current major version of the signing domain.
         *
         * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
         * contract upgrade].
         */
        function __EIP712_init(string memory name, string memory version) internal onlyInitializing {
            __EIP712_init_unchained(name, version);
        }
        function __EIP712_init_unchained(string memory name, string memory version) internal onlyInitializing {
            _name = name;
            _version = version;
            // Reset prior values in storage if upgrading
            _hashedName = 0;
            _hashedVersion = 0;
        }
        /**
         * @dev Returns the domain separator for the current chain.
         */
        function _domainSeparatorV4() internal view returns (bytes32) {
            return _buildDomainSeparator();
        }
        function _buildDomainSeparator() private view returns (bytes32) {
            return keccak256(abi.encode(_TYPE_HASH, _EIP712NameHash(), _EIP712VersionHash(), block.chainid, address(this)));
        }
        /**
         * @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
         * function returns the hash of the fully encoded EIP712 message for this domain.
         *
         * This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
         *
         * ```solidity
         * bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
         *     keccak256("Mail(address to,string contents)"),
         *     mailTo,
         *     keccak256(bytes(mailContents))
         * )));
         * address signer = ECDSA.recover(digest, signature);
         * ```
         */
        function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
            return ECDSAUpgradeable.toTypedDataHash(_domainSeparatorV4(), structHash);
        }
        /**
         * @dev See {EIP-5267}.
         *
         * _Available since v4.9._
         */
        function eip712Domain()
            public
            view
            virtual
            override
            returns (
                bytes1 fields,
                string memory name,
                string memory version,
                uint256 chainId,
                address verifyingContract,
                bytes32 salt,
                uint256[] memory extensions
            )
        {
            // If the hashed name and version in storage are non-zero, the contract hasn't been properly initialized
            // and the EIP712 domain is not reliable, as it will be missing name and version.
            require(_hashedName == 0 && _hashedVersion == 0, "EIP712: Uninitialized");
            return (
                hex"0f", // 01111
                _EIP712Name(),
                _EIP712Version(),
                block.chainid,
                address(this),
                bytes32(0),
                new uint256[](0)
            );
        }
        /**
         * @dev The name parameter for the EIP712 domain.
         *
         * NOTE: This function reads from storage by default, but can be redefined to return a constant value if gas costs
         * are a concern.
         */
        function _EIP712Name() internal virtual view returns (string memory) {
            return _name;
        }
        /**
         * @dev The version parameter for the EIP712 domain.
         *
         * NOTE: This function reads from storage by default, but can be redefined to return a constant value if gas costs
         * are a concern.
         */
        function _EIP712Version() internal virtual view returns (string memory) {
            return _version;
        }
        /**
         * @dev The hash of the name parameter for the EIP712 domain.
         *
         * NOTE: In previous versions this function was virtual. In this version you should override `_EIP712Name` instead.
         */
        function _EIP712NameHash() internal view returns (bytes32) {
            string memory name = _EIP712Name();
            if (bytes(name).length > 0) {
                return keccak256(bytes(name));
            } else {
                // If the name is empty, the contract may have been upgraded without initializing the new storage.
                // We return the name hash in storage if non-zero, otherwise we assume the name is empty by design.
                bytes32 hashedName = _hashedName;
                if (hashedName != 0) {
                    return hashedName;
                } else {
                    return keccak256("");
                }
            }
        }
        /**
         * @dev The hash of the version parameter for the EIP712 domain.
         *
         * NOTE: In previous versions this function was virtual. In this version you should override `_EIP712Version` instead.
         */
        function _EIP712VersionHash() internal view returns (bytes32) {
            string memory version = _EIP712Version();
            if (bytes(version).length > 0) {
                return keccak256(bytes(version));
            } else {
                // If the version is empty, the contract may have been upgraded without initializing the new storage.
                // We return the version hash in storage if non-zero, otherwise we assume the version is empty by design.
                bytes32 hashedVersion = _hashedVersion;
                if (hashedVersion != 0) {
                    return hashedVersion;
                } else {
                    return keccak256("");
                }
            }
        }
        /**
         * @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[48] private __gap;
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts v4.4.1 (utils/Counters.sol)
    pragma solidity ^0.8.0;
    /**
     * @title Counters
     * @author Matt Condon (@shrugs)
     * @dev Provides counters that can only be incremented, decremented or reset. This can be used e.g. to track the number
     * of elements in a mapping, issuing ERC721 ids, or counting request ids.
     *
     * Include with `using Counters for Counters.Counter;`
     */
    library CountersUpgradeable {
        struct Counter {
            // This variable should never be directly accessed by users of the library: interactions must be restricted to
            // the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add
            // this feature: see https://github.com/ethereum/solidity/issues/4637
            uint256 _value; // default: 0
        }
        function current(Counter storage counter) internal view returns (uint256) {
            return counter._value;
        }
        function increment(Counter storage counter) internal {
            unchecked {
                counter._value += 1;
            }
        }
        function decrement(Counter storage counter) internal {
            uint256 value = counter._value;
            require(value > 0, "Counter: decrement overflow");
            unchecked {
                counter._value = value - 1;
            }
        }
        function reset(Counter storage counter) internal {
            counter._value = 0;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.20;
    import {Initializable} from "openzeppelin-upgradeable/proxy/utils/Initializable.sol";
    import {AccessControlEnumerableUpgradeable} from
        "openzeppelin-upgradeable/access/AccessControlEnumerableUpgradeable.sol";
    import {Math} from "openzeppelin/utils/math/Math.sol";
    import {IERC20} from "openzeppelin/token/ERC20/IERC20.sol";
    import {SafeERC20Upgradeable} from "openzeppelin-upgradeable/token/ERC20/utils/SafeERC20Upgradeable.sol";
    import {ProtocolEvents} from "./interfaces/ProtocolEvents.sol";
    import {IDepositContract} from "./interfaces/IDepositContract.sol";
    import {IMETH} from "./interfaces/IMETH.sol";
    import {IOracleReadRecord, OracleRecord} from "./interfaces/IOracle.sol";
    import {IPauserRead} from "./interfaces/IPauser.sol";
    import {IStaking, IStakingReturnsWrite, IStakingInitiationRead} from "./interfaces/IStaking.sol";
    import {UnstakeRequest, IUnstakeRequestsManager} from "./interfaces/IUnstakeRequestsManager.sol";
    /// @notice Events emitted by the staking contract.
    interface StakingEvents {
        /// @notice Emitted when a user stakes ETH and receives mETH.
        /// @param staker The address of the user staking ETH.
        /// @param ethAmount The amount of ETH staked.
        /// @param mETHAmount The amount of mETH received.
        event Staked(address indexed staker, uint256 ethAmount, uint256 mETHAmount);
        /// @notice Emitted when a user unstakes mETH in exchange for ETH.
        /// @param id The ID of the unstake request.
        /// @param staker The address of the user unstaking mETH.
        /// @param ethAmount The amount of ETH that the staker will receive.
        /// @param mETHLocked The amount of mETH that will be burned.
        event UnstakeRequested(uint256 indexed id, address indexed staker, uint256 ethAmount, uint256 mETHLocked);
        /// @notice Emitted when a user claims their unstake request.
        /// @param id The ID of the unstake request.
        /// @param staker The address of the user claiming their unstake request.
        event UnstakeRequestClaimed(uint256 indexed id, address indexed staker);
        /// @notice Emitted when a validator has been initiated (i.e. the protocol has deposited into the deposit contract).
        /// @param id The ID of the validator which is the hash of its pubkey.
        /// @param operatorID The ID of the node operator to which the validator belongs to.
        /// @param pubkey The pubkey of the validator.
        /// @param amountDeposited The amount of ETH deposited into the deposit contract for that validator.
        event ValidatorInitiated(bytes32 indexed id, uint256 indexed operatorID, bytes pubkey, uint256 amountDeposited);
        /// @notice Emitted when the protocol has allocated ETH to the UnstakeRequestsManager.
        /// @param amount The amount of ETH allocated to the UnstakeRequestsManager.
        event AllocatedETHToUnstakeRequestsManager(uint256 amount);
        /// @notice Emitted when the protocol has allocated ETH to use for deposits into the deposit contract.
        /// @param amount The amount of ETH allocated to deposits.
        event AllocatedETHToDeposits(uint256 amount);
        /// @notice Emitted when the protocol has received returns from the returns aggregator.
        /// @param amount The amount of ETH received.
        event ReturnsReceived(uint256 amount);
    }
    /// @title Staking
    /// @notice Manages stake and unstake requests by users, keeps track of the total amount of ETH controlled by the
    /// protocol, and initiates new validators.
    contract Staking is Initializable, AccessControlEnumerableUpgradeable, IStaking, StakingEvents, ProtocolEvents {
        // Errors.
        error DoesNotReceiveETH();
        error InvalidConfiguration();
        error MaximumValidatorDepositExceeded();
        error MaximumMETHSupplyExceeded();
        error MinimumStakeBoundNotSatisfied();
        error MinimumUnstakeBoundNotSatisfied();
        error MinimumValidatorDepositNotSatisfied();
        error NotEnoughDepositETH();
        error NotEnoughUnallocatedETH();
        error NotReturnsAggregator();
        error NotUnstakeRequestsManager();
        error Paused();
        error PreviouslyUsedValidator();
        error ZeroAddress();
        error InvalidDepositRoot(bytes32);
        error StakeBelowMinimumMETHAmount(uint256 methAmount, uint256 expectedMinimum);
        error UnstakeBelowMinimumETHAmount(uint256 ethAmount, uint256 expectedMinimum);
        error InvalidWithdrawalCredentialsWrongLength(uint256);
        error InvalidWithdrawalCredentialsNotETH1(bytes12);
        error InvalidWithdrawalCredentialsWrongAddress(address);
        /// @notice Role allowed trigger administrative tasks such as allocating funds to / withdrawing surplusses from the
        /// UnstakeRequestsManager and setting various parameters on the contract.
        bytes32 public constant STAKING_MANAGER_ROLE = keccak256("STAKING_MANAGER_ROLE");
        /// @notice Role allowed to allocate funds to unstake requests manager and reserve funds to deposit into the
        /// validators.
        bytes32 public constant ALLOCATOR_SERVICE_ROLE = keccak256("ALLOCATER_SERVICE_ROLE");
        /// @notice Role allowed to initiate new validators by sending funds from the allocatedETHForDeposits balance
        /// to the beacon chain deposit contract.
        bytes32 public constant INITIATOR_SERVICE_ROLE = keccak256("INITIATOR_SERVICE_ROLE");
        /// @notice Role to manage the staking allowlist.
        bytes32 public constant STAKING_ALLOWLIST_MANAGER_ROLE = keccak256("STAKING_ALLOWLIST_MANAGER_ROLE");
        /// @notice Role allowed to stake ETH when allowlist is enabled.
        bytes32 public constant STAKING_ALLOWLIST_ROLE = keccak256("STAKING_ALLOWLIST_ROLE");
        /// @notice Role allowed to top up the unallocated ETH in the protocol.
        bytes32 public constant TOP_UP_ROLE = keccak256("TOP_UP_ROLE");
        /// @notice Payload struct submitted for validator initiation.
        /// @dev See also {initiateValidatorsWithDeposits}.
        struct ValidatorParams {
            uint256 operatorID;
            uint256 depositAmount;
            bytes pubkey;
            bytes withdrawalCredentials;
            bytes signature;
            bytes32 depositDataRoot;
        }
        /// @notice Keeps track of already initiated validators.
        /// @dev This is tracked to ensure that we never deposit for the same validator public key twice, which is a base
        /// assumption of this contract and the related off-chain accounting.
        mapping(bytes pubkey => bool exists) public usedValidators;
        /// @inheritdoc IStakingInitiationRead
        /// @dev This is needed to account for ETH that is still in flight, i.e. that has been sent to the deposit contract
        /// but has not been processed by the beacon chain yet. Once the off-chain oracle detects those deposits, they are
        /// recorded as `totalDepositsProcessed` in the oracle contract to avoid double counting. See also
        /// {totalControlled}.
        uint256 public totalDepositedInValidators;
        /// @inheritdoc IStakingInitiationRead
        uint256 public numInitiatedValidators;
        /// @notice The amount of ETH that is used to allocate to deposits and fill the pending unstake requests.
        uint256 public unallocatedETH;
        /// @notice The amount of ETH that is used deposit into validators.
        uint256 public allocatedETHForDeposits;
        /// @notice The minimum amount of ETH users can stake.
        uint256 public minimumStakeBound;
        /// @notice The minimum amount of mETH users can unstake.
        uint256 public minimumUnstakeBound;
        /// @notice When staking on Ethereum, validators must go through an entry queue to bring money into the system, and
        /// an exit queue to bring it back out. The entry queue increases in size as more people want to stake. While the
        /// money is in the entry queue, it is not earning any rewards. When a validator is active, or in the exit queue, it
        /// is earning rewards. Once a validator enters the entry queue, the only way that the money can be retrieved is by
        /// waiting for it to become active and then to exit it again. As of July 2023, the entry queue is approximately 40
        /// days and the exit queue is 0 days (with ~6 days of processing time).
        ///
        /// In a non-optimal scenario for the protocol, a user could stake (for example) 32 ETH to receive mETH, wait
        /// until a validator enters the queue, and then request to unstake to recover their 32 ETH. Now we have 32 ETH in
        /// the system which affects the exchange rate, but is not earning rewards.
        ///
        /// In this case, the 'fair' thing to do would be to make the user wait for the queue processing to finish before
        /// returning their funds. Because the tokens are fungible however, we have no way of matching 'pending' stakes to a
        /// particular user. This means that in order to fulfill unstake requests quickly, we must exit a different
        /// validator to return the user's funds. If we exit a validator, we can return the funds after ~5 days, but the
        /// original 32 ETH will not be earning for another 35 days, leading to a small but repeatable socialised loss of
        /// efficiency for the protocol. As we can only exit validators in chunks of 32 ETH, this case is also exacerbated
        /// by a user unstaking smaller amounts of ETH.
        ///
        /// To compensate for the fact that these two queues differ in length, we apply an adjustment to the exchange rate
        /// to reflect the difference and mitigate its effect on the protocol. This protects the protocol from the case
        /// above, and also from griefing attacks following the same principle. Essentially, when you stake you are
        /// receiving a value of mETH that discounts ~35 days worth of rewards in return for being able to access your
        /// money without waiting the full 40 days when unstaking. As the adjustment is applied to the exchange rate, this
        /// results in a small 'improvement' to the rate for all existing stakers (i.e. it is not a fee levied by the
        /// protocol itself).
        ///
        /// As the adjustment is applied to the exchange rate, the result is reflected in any user interface which shows the
        /// amount of mETH received when staking, meaning there is no surprise for users when staking or unstaking.
        /// @dev The value is in basis points (1/10000).
        uint16 public exchangeAdjustmentRate;
        /// @dev A basis point (often denoted as bp, 1bp = 0.01%) is a unit of measure used in finance to describe
        /// the percentage change in a financial instrument. This is a constant value set as 10000 which represents
        /// 100% in basis point terms.
        uint16 internal constant _BASIS_POINTS_DENOMINATOR = 10_000;
        /// @notice The maximum amount the exchange adjustment rate (10%) that can be set by the admin.
        uint16 internal constant _MAX_EXCHANGE_ADJUSTMENT_RATE = _BASIS_POINTS_DENOMINATOR / 10; // 10%
        /// @notice The minimum amount of ETH that the staking contract can send to the deposit contract to initiate new
        /// validators.
        /// @dev This is used as an additional safeguard to prevent sending deposits that would result in non-activated
        /// validators (since we don't do top-ups), that would need to be exited again to get the ETH back.
        uint256 public minimumDepositAmount;
        /// @notice The maximum amount of ETH that the staking contract can send to the deposit contract to initiate new
        /// validators.
        /// @dev This is used as an additional safeguard to prevent sending too large deposits. While this is not a critical
        /// issue as any surplus >32 ETH (at the time of writing) will automatically be withdrawn again at some point, it is
        /// still undesireable as it locks up not-earning ETH for the duration of the round trip decreasing the efficiency
        /// of the protocol.
        uint256 public maximumDepositAmount;
        /// @notice The beacon chain deposit contract.
        /// @dev ETH will be sent there during validator initiation.
        IDepositContract public depositContract;
        /// @notice The mETH token contract.
        /// @dev Tokens will be minted / burned during staking / unstaking.
        IMETH public mETH;
        /// @notice The oracle contract.
        /// @dev Tracks ETH on the beacon chain and other accounting relevant quantities.
        IOracleReadRecord public oracle;
        /// @notice The pauser contract.
        /// @dev Keeps the pause state across the protocol.
        IPauserRead public pauser;
        /// @notice The contract tracking unstake requests and related allocation and claim operations.
        IUnstakeRequestsManager public unstakeRequestsManager;
        /// @notice The address to receive beacon chain withdrawals (i.e. validator rewards and exits).
        /// @dev Changing this variable will not have an immediate effect as all exisiting validators will still have the
        /// original value set.
        address public withdrawalWallet;
        /// @notice The address for the returns aggregator contract to push funds.
        /// @dev See also {receiveReturns}.
        address public returnsAggregator;
        /// @notice The staking allowlist flag which, when enabled, allows staking only for addresses in allowlist.
        bool public isStakingAllowlist;
        /// @inheritdoc IStakingInitiationRead
        /// @dev This will be used to give off-chain services a sensible point in time to start their analysis from.
        uint256 public initializationBlockNumber;
        /// @notice The maximum amount of mETH that can be minted during the staking process.
        /// @dev This is used as an additional safeguard to create a maximum stake amount in the protocol. As the protocol
        /// scales up this value will be increased to allow for more staking.
        uint256 public maximumMETHSupply;
        /// @notice Configuration for contract initialization.
        struct Init {
            address admin;
            address manager;
            address allocatorService;
            address initiatorService;
            address returnsAggregator;
            address withdrawalWallet;
            IMETH mETH;
            IDepositContract depositContract;
            IOracleReadRecord oracle;
            IPauserRead pauser;
            IUnstakeRequestsManager unstakeRequestsManager;
        }
        constructor() {
            _disableInitializers();
        }
        /// @notice Inititalizes the contract.
        /// @dev MUST be called during the contract upgrade to set up the proxies state.
        function initialize(Init memory init) external initializer {
            __AccessControlEnumerable_init();
            _grantRole(DEFAULT_ADMIN_ROLE, init.admin);
            _grantRole(STAKING_MANAGER_ROLE, init.manager);
            _grantRole(ALLOCATOR_SERVICE_ROLE, init.allocatorService);
            _grantRole(INITIATOR_SERVICE_ROLE, init.initiatorService);
            // Intentionally does not set anyone as the TOP_UP_ROLE as it will only be granted
            // in the off-chance that the top up functionality is required.
            // Set up roles for the staking allowlist. Intentionally do not grant anyone the
            // STAKING_ALLOWLIST_MANAGER_ROLE as it will only be granted later.
            _setRoleAdmin(STAKING_ALLOWLIST_MANAGER_ROLE, STAKING_MANAGER_ROLE);
            _setRoleAdmin(STAKING_ALLOWLIST_ROLE, STAKING_ALLOWLIST_MANAGER_ROLE);
            mETH = init.mETH;
            depositContract = init.depositContract;
            oracle = init.oracle;
            pauser = init.pauser;
            returnsAggregator = init.returnsAggregator;
            unstakeRequestsManager = init.unstakeRequestsManager;
            withdrawalWallet = init.withdrawalWallet;
            minimumStakeBound = 0.1 ether;
            minimumUnstakeBound = 0.01 ether;
            minimumDepositAmount = 32 ether;
            maximumDepositAmount = 32 ether;
            isStakingAllowlist = true;
            initializationBlockNumber = block.number;
            // Set the maximum mETH supply to some sensible amount which is expected to be changed as the
            // protocol ramps up.
            maximumMETHSupply = 1024 ether;
        }
        /// @notice Interface for users to stake their ETH with the protocol. Note: when allowlist is enabled, only users
        /// with the allowlist can stake.
        /// @dev Mints the corresponding amount of mETH (relative to the stake's share in the total ETH controlled by the
        /// protocol) to the user.
        /// @param minMETHAmount The minimum amount of mETH that the user expects to receive in return.
        function stake(uint256 minMETHAmount) external payable {
            if (pauser.isStakingPaused()) {
                revert Paused();
            }
            if (isStakingAllowlist) {
                _checkRole(STAKING_ALLOWLIST_ROLE);
            }
            if (msg.value < minimumStakeBound) {
                revert MinimumStakeBoundNotSatisfied();
            }
            uint256 mETHMintAmount = ethToMETH(msg.value);
            if (mETHMintAmount + mETH.totalSupply() > maximumMETHSupply) {
                revert MaximumMETHSupplyExceeded();
            }
            if (mETHMintAmount < minMETHAmount) {
                revert StakeBelowMinimumMETHAmount(mETHMintAmount, minMETHAmount);
            }
            // Increment unallocated ETH after calculating the exchange rate to ensure
            // a consistent rate.
            unallocatedETH += msg.value;
            emit Staked(msg.sender, msg.value, mETHMintAmount);
            mETH.mint(msg.sender, mETHMintAmount);
        }
        /// @notice Interface for users to submit a request to unstake.
        /// @dev Transfers the specified amount of mETH to the staking contract and locks it there until it is burned on
        /// request claim. The staking contract must therefore be approved to move the user's mETH on their behalf.
        /// @param methAmount The amount of mETH to unstake.
        /// @param minETHAmount The minimum amount of ETH that the user expects to receive.
        /// @return The request ID.
        function unstakeRequest(uint128 methAmount, uint128 minETHAmount) external returns (uint256) {
            return _unstakeRequest(methAmount, minETHAmount);
        }
        /// @notice Interface for users to submit a request to unstake with an ERC20 permit.
        /// @dev Transfers the specified amount of mETH to the staking contract and locks it there until it is burned on
        /// request claim. The permit must therefore allow the staking contract to move the user's mETH on their behalf.
        /// @return The request ID.
        function unstakeRequestWithPermit(
            uint128 methAmount,
            uint128 minETHAmount,
            uint256 deadline,
            uint8 v,
            bytes32 r,
            bytes32 s
        ) external returns (uint256) {
            SafeERC20Upgradeable.safePermit(mETH, msg.sender, address(this), methAmount, deadline, v, r, s);
            return _unstakeRequest(methAmount, minETHAmount);
        }
        /// @notice Processes a user's request to unstake by transferring the corresponding mETH to the staking contract
        /// and creating the request on the unstake requests manager.
        /// @param methAmount The amount of mETH to unstake.
        /// @param minETHAmount The minimum amount of ETH that the user expects to receive.
        function _unstakeRequest(uint128 methAmount, uint128 minETHAmount) internal returns (uint256) {
            if (pauser.isUnstakeRequestsAndClaimsPaused()) {
                revert Paused();
            }
            if (methAmount < minimumUnstakeBound) {
                revert MinimumUnstakeBoundNotSatisfied();
            }
            uint128 ethAmount = uint128(mETHToETH(methAmount));
            if (ethAmount < minETHAmount) {
                revert UnstakeBelowMinimumETHAmount(ethAmount, minETHAmount);
            }
            uint256 requestID =
                unstakeRequestsManager.create({requester: msg.sender, mETHLocked: methAmount, ethRequested: ethAmount});
            emit UnstakeRequested({id: requestID, staker: msg.sender, ethAmount: ethAmount, mETHLocked: methAmount});
            SafeERC20Upgradeable.safeTransferFrom(mETH, msg.sender, address(unstakeRequestsManager), methAmount);
            return requestID;
        }
        /// @notice Interface for users to claim their finalized and filled unstaking requests.
        /// @dev See also {UnstakeRequestsManager} for a more detailed explanation of finalization and request filling.
        function claimUnstakeRequest(uint256 unstakeRequestID) external {
            if (pauser.isUnstakeRequestsAndClaimsPaused()) {
                revert Paused();
            }
            emit UnstakeRequestClaimed(unstakeRequestID, msg.sender);
            unstakeRequestsManager.claim(unstakeRequestID, msg.sender);
        }
        /// @notice Returns the status of the request whether it is finalized and how much ETH has been filled.
        /// See also {UnstakeRequestsManager.requestInfo} for a more detailed explanation of finalization and request
        /// filling.
        /// @param unstakeRequestID The ID of the unstake request.
        /// @return bool indicating if the unstake request is finalized, and the amount of ETH that has been filled.
        function unstakeRequestInfo(uint256 unstakeRequestID) external view returns (bool, uint256) {
            return unstakeRequestsManager.requestInfo(unstakeRequestID);
        }
        /// @notice Withdraws any surplus from the unstake requests manager.
        /// @dev The request manager is expected to return the funds by pushing them using
        /// {receiveFromUnstakeRequestsManager}.
        function reclaimAllocatedETHSurplus() external onlyRole(STAKING_MANAGER_ROLE) {
            // Calls the receiveFromUnstakeRequestsManager() where we perform
            // the accounting.
            unstakeRequestsManager.withdrawAllocatedETHSurplus();
        }
        /// @notice Allocates ETH from the unallocatedETH balance to the unstake requests manager to fill pending requests
        /// and adds to the allocatedETHForDeposits balance that is used to initiate new validators.
        function allocateETH(uint256 allocateToUnstakeRequestsManager, uint256 allocateToDeposits)
            external
            onlyRole(ALLOCATOR_SERVICE_ROLE)
        {
            if (pauser.isAllocateETHPaused()) {
                revert Paused();
            }
            if (allocateToUnstakeRequestsManager + allocateToDeposits > unallocatedETH) {
                revert NotEnoughUnallocatedETH();
            }
            unallocatedETH -= allocateToUnstakeRequestsManager + allocateToDeposits;
            if (allocateToDeposits > 0) {
                allocatedETHForDeposits += allocateToDeposits;
                emit AllocatedETHToDeposits(allocateToDeposits);
            }
            if (allocateToUnstakeRequestsManager > 0) {
                emit AllocatedETHToUnstakeRequestsManager(allocateToUnstakeRequestsManager);
                unstakeRequestsManager.allocateETH{value: allocateToUnstakeRequestsManager}();
            }
        }
        /// @notice Initiates new validators by sending ETH to the beacon chain deposit contract.
        /// @dev Cannot initiate the same validator (public key) twice. Since BLS signatures cannot be feasibly verified on
        /// the EVM, the caller must carefully make sure that the sent payloads (public keys + signatures) are correct,
        /// otherwise the sent ETH will be lost.
        function initiateValidatorsWithDeposits(ValidatorParams[] calldata validators, bytes32 expectedDepositRoot)
            external
            onlyRole(INITIATOR_SERVICE_ROLE)
        {
            if (pauser.isInitiateValidatorsPaused()) {
                revert Paused();
            }
            if (validators.length == 0) {
                return;
            }
            // Check that the deposit root matches the given value. This ensures that the deposit contract state
            // has not changed since the transaction was submitted, which means that a rogue node operator cannot
            // front-run deposit transactions.
            bytes32 actualRoot = depositContract.get_deposit_root();
            if (expectedDepositRoot != actualRoot) {
                revert InvalidDepositRoot(actualRoot);
            }
            // First loop is to check that all validators are valid according to our constraints and we record the
            // validators and how much we have deposited.
            uint256 amountDeposited = 0;
            for (uint256 i = 0; i < validators.length; ++i) {
                ValidatorParams calldata validator = validators[i];
                if (usedValidators[validator.pubkey]) {
                    revert PreviouslyUsedValidator();
                }
                if (validator.depositAmount < minimumDepositAmount) {
                    revert MinimumValidatorDepositNotSatisfied();
                }
                if (validator.depositAmount > maximumDepositAmount) {
                    revert MaximumValidatorDepositExceeded();
                }
                _requireProtocolWithdrawalAccount(validator.withdrawalCredentials);
                usedValidators[validator.pubkey] = true;
                amountDeposited += validator.depositAmount;
                emit ValidatorInitiated({
                    id: keccak256(validator.pubkey),
                    operatorID: validator.operatorID,
                    pubkey: validator.pubkey,
                    amountDeposited: validator.depositAmount
                });
            }
            if (amountDeposited > allocatedETHForDeposits) {
                revert NotEnoughDepositETH();
            }
            allocatedETHForDeposits -= amountDeposited;
            totalDepositedInValidators += amountDeposited;
            numInitiatedValidators += validators.length;
            // Second loop is to send the deposits to the deposit contract. Keeps external calls to the deposit contract
            // separate from state changes.
            for (uint256 i = 0; i < validators.length; ++i) {
                ValidatorParams calldata validator = validators[i];
                depositContract.deposit{value: validator.depositAmount}({
                    pubkey: validator.pubkey,
                    withdrawal_credentials: validator.withdrawalCredentials,
                    signature: validator.signature,
                    deposit_data_root: validator.depositDataRoot
                });
            }
        }
        /// @inheritdoc IStakingReturnsWrite
        /// @dev Intended to be the called in the same transaction initiated by reclaimAllocatedETHSurplus().
        /// This should only be called in emergency scenarios, e.g. if the unstake requests manager has cancelled
        /// unfinalized requests and there is a surplus balance.
        /// Adds the received funds to the unallocated balance.
        function receiveFromUnstakeRequestsManager() external payable onlyUnstakeRequestsManager {
            unallocatedETH += msg.value;
        }
        /// @notice Tops up the unallocated ETH balance to increase the amount of ETH in the protocol.
        /// @dev Bypasses the returns aggregator fee collection to inject ETH directly into the protocol.
        function topUp() external payable onlyRole(TOP_UP_ROLE) {
            unallocatedETH += msg.value;
        }
        /// @notice Converts from mETH to ETH using the current exchange rate.
        /// The exchange rate is given by the total supply of mETH and total ETH controlled by the protocol.
        function ethToMETH(uint256 ethAmount) public view returns (uint256) {
            // 1:1 exchange rate on the first stake.
            // Using `METH.totalSupply` over `totalControlled` to check if the protocol is in its bootstrap phase since
            // the latter can be manipulated, for example by transferring funds to the `ExecutionLayerReturnsReceiver`, and
            // therefore be non-zero by the time the first stake is made
            if (mETH.totalSupply() == 0) {
                return ethAmount;
            }
            // deltaMETH = (1 - exchangeAdjustmentRate) * (mETHSupply / totalControlled) * ethAmount
            // This rounds down to zero in the case of `(1 - exchangeAdjustmentRate) * ethAmount * mETHSupply <
            // totalControlled`.
            // While this scenario is theoretically possible, it can only be realised feasibly during the protocol's
            // bootstrap phase and if `totalControlled` and `mETHSupply` can be changed independently of each other. Since
            // the former is permissioned, and the latter is not permitted by the protocol, this cannot be exploited by an
            // attacker.
            return Math.mulDiv(
                ethAmount,
                mETH.totalSupply() * uint256(_BASIS_POINTS_DENOMINATOR - exchangeAdjustmentRate),
                totalControlled() * uint256(_BASIS_POINTS_DENOMINATOR)
            );
        }
        /// @notice Converts from ETH to mETH using the current exchange rate.
        /// The exchange rate is given by the total supply of mETH and total ETH controlled by the protocol.
        function mETHToETH(uint256 mETHAmount) public view returns (uint256) {
            // 1:1 exchange rate on the first stake.
            // Using `METH.totalSupply` over `totalControlled` to check if the protocol is in its bootstrap phase since
            // the latter can be manipulated, for example by transferring funds to the `ExecutionLayerReturnsReceiver`, and
            // therefore be non-zero by the time the first stake is made
            if (mETH.totalSupply() == 0) {
                return mETHAmount;
            }
            // deltaETH = (totalControlled / mETHSupply) * mETHAmount
            // This rounds down to zero in the case of `mETHAmount * totalControlled < mETHSupply`.
            // While this scenario is theoretically possible, it can only be realised feasibly during the protocol's
            // bootstrap phase and if `totalControlled` and `mETHSupply` can be changed independently of each other. Since
            // the former is permissioned, and the latter is not permitted by the protocol, this cannot be exploited by an
            // attacker.
            return Math.mulDiv(mETHAmount, totalControlled(), mETH.totalSupply());
        }
        /// @notice The total amount of ETH controlled by the protocol.
        /// @dev Sums over the balances of various contracts and the beacon chain information from the oracle.
        function totalControlled() public view returns (uint256) {
            OracleRecord memory record = oracle.latestRecord();
            uint256 total = 0;
            total += unallocatedETH;
            total += allocatedETHForDeposits;
            /// The total ETH deposited to the beacon chain must be decreased by the deposits processed by the off-chain
            /// oracle since it will be accounted for in the currentTotalValidatorBalance from that point onwards.
            total += totalDepositedInValidators - record.cumulativeProcessedDepositAmount;
            total += record.currentTotalValidatorBalance;
            total += unstakeRequestsManager.balance();
            return total;
        }
        /// @notice Checks if the given withdrawal credentials are a valid 0x01 prefixed withdrawal address.
        /// @dev See also
        /// https://github.com/ethereum/consensus-specs/blob/master/specs/phase0/validator.md#eth1_address_withdrawal_prefix
        function _requireProtocolWithdrawalAccount(bytes calldata withdrawalCredentials) internal view {
            if (withdrawalCredentials.length != 32) {
                revert InvalidWithdrawalCredentialsWrongLength(withdrawalCredentials.length);
            }
            // Check the ETH1_ADDRESS_WITHDRAWAL_PREFIX and that all other bytes are zero.
            bytes12 prefixAndPadding = bytes12(withdrawalCredentials[:12]);
            if (prefixAndPadding != 0x010000000000000000000000) {
                revert InvalidWithdrawalCredentialsNotETH1(prefixAndPadding);
            }
            address addr = address(bytes20(withdrawalCredentials[12:32]));
            if (addr != withdrawalWallet) {
                revert InvalidWithdrawalCredentialsWrongAddress(addr);
            }
        }
        /// @inheritdoc IStakingReturnsWrite
        /// @dev Adds the received funds to the unallocated balance.
        function receiveReturns() external payable onlyReturnsAggregator {
            emit ReturnsReceived(msg.value);
            unallocatedETH += msg.value;
        }
        /// @notice Ensures that the caller is the returns aggregator.
        modifier onlyReturnsAggregator() {
            if (msg.sender != returnsAggregator) {
                revert NotReturnsAggregator();
            }
            _;
        }
        /// @notice Ensures that the caller is the unstake requests manager.
        modifier onlyUnstakeRequestsManager() {
            if (msg.sender != address(unstakeRequestsManager)) {
                revert NotUnstakeRequestsManager();
            }
            _;
        }
        /// @notice Ensures that the given address is not the zero address.
        modifier notZeroAddress(address addr) {
            if (addr == address(0)) {
                revert ZeroAddress();
            }
            _;
        }
        /// @notice Sets the minimum amount of ETH users can stake.
        function setMinimumStakeBound(uint256 minimumStakeBound_) external onlyRole(STAKING_MANAGER_ROLE) {
            minimumStakeBound = minimumStakeBound_;
            emit ProtocolConfigChanged(
                this.setMinimumStakeBound.selector, "setMinimumStakeBound(uint256)", abi.encode(minimumStakeBound_)
            );
        }
        /// @notice Sets the minimum amount of mETH users can unstake.
        function setMinimumUnstakeBound(uint256 minimumUnstakeBound_) external onlyRole(STAKING_MANAGER_ROLE) {
            minimumUnstakeBound = minimumUnstakeBound_;
            emit ProtocolConfigChanged(
                this.setMinimumUnstakeBound.selector, "setMinimumUnstakeBound(uint256)", abi.encode(minimumUnstakeBound_)
            );
        }
        /// @notice Sets the staking adjust rate.
        function setExchangeAdjustmentRate(uint16 exchangeAdjustmentRate_) external onlyRole(STAKING_MANAGER_ROLE) {
            if (exchangeAdjustmentRate_ > _MAX_EXCHANGE_ADJUSTMENT_RATE) {
                revert InvalidConfiguration();
            }
            // even though this check is redundant with the one above, this function will be rarely used so we keep it as a
            // reminder for future upgrades that this must never be violated.
            assert(exchangeAdjustmentRate_ <= _BASIS_POINTS_DENOMINATOR);
            exchangeAdjustmentRate = exchangeAdjustmentRate_;
            emit ProtocolConfigChanged(
                this.setExchangeAdjustmentRate.selector,
                "setExchangeAdjustmentRate(uint16)",
                abi.encode(exchangeAdjustmentRate_)
            );
        }
        /// @notice Sets the minimum amount of ETH that the staking contract can send to the deposit contract to initiate
        /// new validators.
        function setMinimumDepositAmount(uint256 minimumDepositAmount_) external onlyRole(STAKING_MANAGER_ROLE) {
            minimumDepositAmount = minimumDepositAmount_;
            emit ProtocolConfigChanged(
                this.setMinimumDepositAmount.selector, "setMinimumDepositAmount(uint256)", abi.encode(minimumDepositAmount_)
            );
        }
        /// @notice Sets the maximum amount of ETH that the staking contract can send to the deposit contract to initiate
        /// new validators.
        function setMaximumDepositAmount(uint256 maximumDepositAmount_) external onlyRole(STAKING_MANAGER_ROLE) {
            maximumDepositAmount = maximumDepositAmount_;
            emit ProtocolConfigChanged(
                this.setMaximumDepositAmount.selector, "setMaximumDepositAmount(uint256)", abi.encode(maximumDepositAmount_)
            );
        }
        /// @notice Sets the maximumMETHSupply variable.
        /// Note: We intentionally allow this to be set lower than the current totalSupply so that the amount can be
        /// adjusted downwards by unstaking.
        /// See also {maximumMETHSupply}.
        function setMaximumMETHSupply(uint256 maximumMETHSupply_) external onlyRole(STAKING_MANAGER_ROLE) {
            maximumMETHSupply = maximumMETHSupply_;
            emit ProtocolConfigChanged(
                this.setMaximumMETHSupply.selector, "setMaximumMETHSupply(uint256)", abi.encode(maximumMETHSupply_)
            );
        }
        /// @notice Sets the address to receive beacon chain withdrawals (i.e. validator rewards and exits).
        /// @dev Changing this variable will not have an immediate effect as all exisiting validators will still have the
        /// original value set.
        function setWithdrawalWallet(address withdrawalWallet_)
            external
            onlyRole(STAKING_MANAGER_ROLE)
            notZeroAddress(withdrawalWallet_)
        {
            withdrawalWallet = withdrawalWallet_;
            emit ProtocolConfigChanged(
                this.setWithdrawalWallet.selector, "setWithdrawalWallet(address)", abi.encode(withdrawalWallet_)
            );
        }
        /// @notice Sets the staking allowlist flag.
        function setStakingAllowlist(bool isStakingAllowlist_) external onlyRole(STAKING_MANAGER_ROLE) {
            isStakingAllowlist = isStakingAllowlist_;
            emit ProtocolConfigChanged(
                this.setStakingAllowlist.selector, "setStakingAllowlist(bool)", abi.encode(isStakingAllowlist_)
            );
        }
        receive() external payable {
            revert DoesNotReceiveETH();
        }
        fallback() external payable {
            revert DoesNotReceiveETH();
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts v4.4.1 (access/IAccessControl.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev External interface of AccessControl declared to support ERC165 detection.
     */
    interface IAccessControlUpgradeable {
        /**
         * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
         *
         * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
         * {RoleAdminChanged} not being emitted signaling this.
         *
         * _Available since v3.1._
         */
        event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);
        /**
         * @dev Emitted when `account` is granted `role`.
         *
         * `sender` is the account that originated the contract call, an admin role
         * bearer except when using {AccessControl-_setupRole}.
         */
        event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);
        /**
         * @dev Emitted when `account` is revoked `role`.
         *
         * `sender` is the account that originated the contract call:
         *   - if using `revokeRole`, it is the admin role bearer
         *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
         */
        event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);
        /**
         * @dev Returns `true` if `account` has been granted `role`.
         */
        function hasRole(bytes32 role, address account) external view returns (bool);
        /**
         * @dev Returns the admin role that controls `role`. See {grantRole} and
         * {revokeRole}.
         *
         * To change a role's admin, use {AccessControl-_setRoleAdmin}.
         */
        function getRoleAdmin(bytes32 role) external view returns (bytes32);
        /**
         * @dev Grants `role` to `account`.
         *
         * If `account` had not been already granted `role`, emits a {RoleGranted}
         * event.
         *
         * Requirements:
         *
         * - the caller must have ``role``'s admin role.
         */
        function grantRole(bytes32 role, address account) external;
        /**
         * @dev Revokes `role` from `account`.
         *
         * If `account` had been granted `role`, emits a {RoleRevoked} event.
         *
         * Requirements:
         *
         * - the caller must have ``role``'s admin role.
         */
        function revokeRole(bytes32 role, address account) external;
        /**
         * @dev Revokes `role` from the calling account.
         *
         * Roles are often managed via {grantRole} and {revokeRole}: this function's
         * purpose is to provide a mechanism for accounts to lose their privileges
         * if they are compromised (such as when a trusted device is misplaced).
         *
         * If the calling account had been granted `role`, emits a {RoleRevoked}
         * event.
         *
         * Requirements:
         *
         * - the caller must be `account`.
         */
        function renounceRole(bytes32 role, address account) external;
    }
    // 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/Strings.sol)
    pragma solidity ^0.8.0;
    import "./math/MathUpgradeable.sol";
    import "./math/SignedMathUpgradeable.sol";
    /**
     * @dev String operations.
     */
    library StringsUpgradeable {
        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 = MathUpgradeable.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(SignedMathUpgradeable.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, MathUpgradeable.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));
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
    pragma solidity ^0.8.0;
    import "./IERC165Upgradeable.sol";
    import "../../proxy/utils/Initializable.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 ERC165Upgradeable is Initializable, IERC165Upgradeable {
        function __ERC165_init() internal onlyInitializing {
        }
        function __ERC165_init_unchained() internal onlyInitializing {
        }
        /**
         * @dev See {IERC165-supportsInterface}.
         */
        function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
            return interfaceId == type(IERC165Upgradeable).interfaceId;
        }
        /**
         * @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 v4.4.1 (access/IAccessControl.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev External interface of AccessControl declared to support ERC165 detection.
     */
    interface IAccessControl {
        /**
         * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
         *
         * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
         * {RoleAdminChanged} not being emitted signaling this.
         *
         * _Available since v3.1._
         */
        event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);
        /**
         * @dev Emitted when `account` is granted `role`.
         *
         * `sender` is the account that originated the contract call, an admin role
         * bearer except when using {AccessControl-_setupRole}.
         */
        event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);
        /**
         * @dev Emitted when `account` is revoked `role`.
         *
         * `sender` is the account that originated the contract call:
         *   - if using `revokeRole`, it is the admin role bearer
         *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
         */
        event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);
        /**
         * @dev Returns `true` if `account` has been granted `role`.
         */
        function hasRole(bytes32 role, address account) external view returns (bool);
        /**
         * @dev Returns the admin role that controls `role`. See {grantRole} and
         * {revokeRole}.
         *
         * To change a role's admin, use {AccessControl-_setRoleAdmin}.
         */
        function getRoleAdmin(bytes32 role) external view returns (bytes32);
        /**
         * @dev Grants `role` to `account`.
         *
         * If `account` had not been already granted `role`, emits a {RoleGranted}
         * event.
         *
         * Requirements:
         *
         * - the caller must have ``role``'s admin role.
         */
        function grantRole(bytes32 role, address account) external;
        /**
         * @dev Revokes `role` from `account`.
         *
         * If `account` had been granted `role`, emits a {RoleRevoked} event.
         *
         * Requirements:
         *
         * - the caller must have ``role``'s admin role.
         */
        function revokeRole(bytes32 role, address account) external;
        /**
         * @dev Revokes `role` from the calling account.
         *
         * Roles are often managed via {grantRole} and {revokeRole}: this function's
         * purpose is to provide a mechanism for accounts to lose their privileges
         * if they are compromised (such as when a trusted device is misplaced).
         *
         * If the calling account had been granted `role`, emits a {RoleRevoked}
         * event.
         *
         * Requirements:
         *
         * - the caller must be `account`.
         */
        function renounceRole(bytes32 role, address account) external;
    }
    // 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 v4.8.0) (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));
        }
    }
    // 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 (last updated v4.9.0) (token/ERC20/IERC20.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev Interface of the ERC20 standard as defined in the EIP.
     */
    interface IERC20Upgradeable {
        /**
         * @dev Emitted when `value` tokens are moved from one account (`from`) to
         * another (`to`).
         *
         * Note that `value` may be zero.
         */
        event Transfer(address indexed from, address indexed to, uint256 value);
        /**
         * @dev Emitted when the allowance of a `spender` for an `owner` is set by
         * a call to {approve}. `value` is the new allowance.
         */
        event Approval(address indexed owner, address indexed spender, uint256 value);
        /**
         * @dev Returns the amount of tokens in existence.
         */
        function totalSupply() external view returns (uint256);
        /**
         * @dev Returns the amount of tokens owned by `account`.
         */
        function balanceOf(address account) external view returns (uint256);
        /**
         * @dev Moves `amount` tokens from the caller's account to `to`.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transfer(address to, uint256 amount) external returns (bool);
        /**
         * @dev Returns the remaining number of tokens that `spender` will be
         * allowed to spend on behalf of `owner` through {transferFrom}. This is
         * zero by default.
         *
         * This value changes when {approve} or {transferFrom} are called.
         */
        function allowance(address owner, address spender) external view returns (uint256);
        /**
         * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * IMPORTANT: Beware that changing an allowance with this method brings the risk
         * that someone may use both the old and the new allowance by unfortunate
         * transaction ordering. One possible solution to mitigate this race
         * condition is to first reduce the spender's allowance to 0 and set the
         * desired value afterwards:
         * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
         *
         * Emits an {Approval} event.
         */
        function approve(address spender, uint256 amount) external returns (bool);
        /**
         * @dev Moves `amount` tokens from `from` to `to` using the
         * allowance mechanism. `amount` is then deducted from the caller's
         * allowance.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transferFrom(address from, address to, uint256 amount) external returns (bool);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)
    pragma solidity ^0.8.0;
    import "../IERC20Upgradeable.sol";
    /**
     * @dev Interface for the optional metadata functions from the ERC20 standard.
     *
     * _Available since v4.1._
     */
    interface IERC20MetadataUpgradeable is IERC20Upgradeable {
        /**
         * @dev Returns the name of the token.
         */
        function name() external view returns (string memory);
        /**
         * @dev Returns the symbol of the token.
         */
        function symbol() external view returns (string memory);
        /**
         * @dev Returns the decimals places of the token.
         */
        function decimals() external view returns (uint8);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.9.0) (interfaces/IERC5267.sol)
    pragma solidity ^0.8.0;
    interface IERC5267Upgradeable {
        /**
         * @dev MAY be emitted to signal that the domain could have changed.
         */
        event EIP712DomainChanged();
        /**
         * @dev returns the fields and values that describe the domain separator used by this contract for EIP-712
         * signature.
         */
        function eip712Domain()
            external
            view
            returns (
                bytes1 fields,
                string memory name,
                string memory version,
                uint256 chainId,
                address verifyingContract,
                bytes32 salt,
                uint256[] memory extensions
            );
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.8.0) (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 v4.6.0) (token/ERC20/IERC20.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev Interface of the ERC20 standard as defined in the EIP.
     */
    interface IERC20 {
        /**
         * @dev Emitted when `value` tokens are moved from one account (`from`) to
         * another (`to`).
         *
         * Note that `value` may be zero.
         */
        event Transfer(address indexed from, address indexed to, uint256 value);
        /**
         * @dev Emitted when the allowance of a `spender` for an `owner` is set by
         * a call to {approve}. `value` is the new allowance.
         */
        event Approval(address indexed owner, address indexed spender, uint256 value);
        /**
         * @dev Returns the amount of tokens in existence.
         */
        function totalSupply() external view returns (uint256);
        /**
         * @dev Returns the amount of tokens owned by `account`.
         */
        function balanceOf(address account) external view returns (uint256);
        /**
         * @dev Moves `amount` tokens from the caller's account to `to`.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transfer(address to, uint256 amount) external returns (bool);
        /**
         * @dev Returns the remaining number of tokens that `spender` will be
         * allowed to spend on behalf of `owner` through {transferFrom}. This is
         * zero by default.
         *
         * This value changes when {approve} or {transferFrom} are called.
         */
        function allowance(address owner, address spender) external view returns (uint256);
        /**
         * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * IMPORTANT: Beware that changing an allowance with this method brings the risk
         * that someone may use both the old and the new allowance by unfortunate
         * transaction ordering. One possible solution to mitigate this race
         * condition is to first reduce the spender's allowance to 0 and set the
         * desired value afterwards:
         * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
         *
         * Emits an {Approval} event.
         */
        function approve(address spender, uint256 amount) external returns (bool);
        /**
         * @dev Moves `amount` tokens from `from` to `to` using the
         * allowance mechanism. `amount` is then deducted from the caller's
         * allowance.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transferFrom(address from, address to, uint256 amount) external returns (bool);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/utils/SafeERC20.sol)
    pragma solidity ^0.8.0;
    import "../IERC20Upgradeable.sol";
    import "../extensions/IERC20PermitUpgradeable.sol";
    import "../../../utils/AddressUpgradeable.sol";
    /**
     * @title SafeERC20
     * @dev Wrappers around ERC20 operations that throw on failure (when the token
     * contract returns false). Tokens that return no value (and instead revert or
     * throw on failure) are also supported, non-reverting calls are assumed to be
     * successful.
     * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
     * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
     */
    library SafeERC20Upgradeable {
        using AddressUpgradeable for address;
        /**
         * @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
         * non-reverting calls are assumed to be successful.
         */
        function safeTransfer(IERC20Upgradeable token, address to, uint256 value) internal {
            _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
        }
        /**
         * @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
         * calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
         */
        function safeTransferFrom(IERC20Upgradeable token, address from, address to, uint256 value) internal {
            _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
        }
        /**
         * @dev Deprecated. This function has issues similar to the ones found in
         * {IERC20-approve}, and its usage is discouraged.
         *
         * Whenever possible, use {safeIncreaseAllowance} and
         * {safeDecreaseAllowance} instead.
         */
        function safeApprove(IERC20Upgradeable token, address spender, uint256 value) internal {
            // safeApprove should only be called when setting an initial allowance,
            // or when resetting it to zero. To increase and decrease it, use
            // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
            require(
                (value == 0) || (token.allowance(address(this), spender) == 0),
                "SafeERC20: approve from non-zero to non-zero allowance"
            );
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
        }
        /**
         * @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
         * non-reverting calls are assumed to be successful.
         */
        function safeIncreaseAllowance(IERC20Upgradeable token, address spender, uint256 value) internal {
            uint256 oldAllowance = token.allowance(address(this), spender);
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance + value));
        }
        /**
         * @dev Decrease the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
         * non-reverting calls are assumed to be successful.
         */
        function safeDecreaseAllowance(IERC20Upgradeable token, address spender, uint256 value) internal {
            unchecked {
                uint256 oldAllowance = token.allowance(address(this), spender);
                require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
                _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance - value));
            }
        }
        /**
         * @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
         * non-reverting calls are assumed to be successful. Compatible with tokens that require the approval to be set to
         * 0 before setting it to a non-zero value.
         */
        function forceApprove(IERC20Upgradeable token, address spender, uint256 value) internal {
            bytes memory approvalCall = abi.encodeWithSelector(token.approve.selector, spender, value);
            if (!_callOptionalReturnBool(token, approvalCall)) {
                _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, 0));
                _callOptionalReturn(token, approvalCall);
            }
        }
        /**
         * @dev Use a ERC-2612 signature to set the `owner` approval toward `spender` on `token`.
         * Revert on invalid signature.
         */
        function safePermit(
            IERC20PermitUpgradeable token,
            address owner,
            address spender,
            uint256 value,
            uint256 deadline,
            uint8 v,
            bytes32 r,
            bytes32 s
        ) internal {
            uint256 nonceBefore = token.nonces(owner);
            token.permit(owner, spender, value, deadline, v, r, s);
            uint256 nonceAfter = token.nonces(owner);
            require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
        }
        /**
         * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
         * on the return value: the return value is optional (but if data is returned, it must not be false).
         * @param token The token targeted by the call.
         * @param data The call data (encoded using abi.encode or one of its variants).
         */
        function _callOptionalReturn(IERC20Upgradeable token, bytes memory data) private {
            // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
            // we're implementing it ourselves. We use {Address-functionCall} to perform this call, which verifies that
            // the target address contains contract code and also asserts for success in the low-level call.
            bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
            require(returndata.length == 0 || abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
        /**
         * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
         * on the return value: the return value is optional (but if data is returned, it must not be false).
         * @param token The token targeted by the call.
         * @param data The call data (encoded using abi.encode or one of its variants).
         *
         * This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
         */
        function _callOptionalReturnBool(IERC20Upgradeable token, bytes memory data) private returns (bool) {
            // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
            // we're implementing it ourselves. We cannot use {Address-functionCall} here since this should return false
            // and not revert is the subcall reverts.
            (bool success, bytes memory returndata) = address(token).call(data);
            return
                success && (returndata.length == 0 || abi.decode(returndata, (bool))) && AddressUpgradeable.isContract(address(token));
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.20;
    interface ProtocolEvents {
        /// @notice Emitted when a protocol configuration has been updated.
        /// @param setterSelector The selector of the function that updated the configuration.
        /// @param setterSignature The signature of the function that updated the configuration.
        /// @param value The abi-encoded data passed to the function that updated the configuration. Since this event will
        /// only be emitted by setters, this data corresponds to the updated values in the protocol configuration.
        event ProtocolConfigChanged(bytes4 indexed setterSelector, string setterSignature, bytes value);
    }
    // ┏━━━┓━┏┓━┏┓━━┏━━━┓━━┏━━━┓━━━━┏━━━┓━━━━━━━━━━━━━━━━━━━┏┓━━━━━┏━━━┓━━━━━━━━━┏┓━━━━━━━━━━━━━━┏┓━
    // ┃┏━━┛┏┛┗┓┃┃━━┃┏━┓┃━━┃┏━┓┃━━━━┗┓┏┓┃━━━━━━━━━━━━━━━━━━┏┛┗┓━━━━┃┏━┓┃━━━━━━━━┏┛┗┓━━━━━━━━━━━━┏┛┗┓
    // ┃┗━━┓┗┓┏┛┃┗━┓┗┛┏┛┃━━┃┃━┃┃━━━━━┃┃┃┃┏━━┓┏━━┓┏━━┓┏━━┓┏┓┗┓┏┛━━━━┃┃━┗┛┏━━┓┏━┓━┗┓┏┛┏━┓┏━━┓━┏━━┓┗┓┏┛
    // ┃┏━━┛━┃┃━┃┏┓┃┏━┛┏┛━━┃┃━┃┃━━━━━┃┃┃┃┃┏┓┃┃┏┓┃┃┏┓┃┃━━┫┣┫━┃��━━━━━┃┃━┏┓┃┏┓┃┃┏┓┓━┃┃━┃┏┛┗━┓┃━┃┏━┛━┃┃━
    // ┃┗━━┓━┃┗┓┃┃┃┃┃┃┗━┓┏┓┃┗━┛┃━━━━┏┛┗┛┃┃┃━┫┃┗┛┃┃┗┛┃┣━━┃┃┃━┃┗┓━━━━┃┗━┛┃┃┗┛┃┃┃┃┃━┃┗┓┃┃━┃┗┛┗┓┃┗━┓━┃┗┓
    // ┗━━━┛━┗━┛┗┛┗┛┗━━━┛┗┛┗━━━┛━━━━┗━━━┛┗━━┛┃┏━┛┗━━┛┗━━┛┗┛━┗━┛━━━━┗━━━┛┗━━┛┗┛┗┛━┗━┛┗┛━┗━━━┛┗━━┛━┗━┛
    // ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┃┃━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
    // ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┗┛━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
    //
    // From: https://github.com/ethereum/consensus-specs/blob/dev/solidity_deposit_contract/deposit_contract.sol
    // SPDX-License-Identifier: CC0-1.0
    pragma solidity ^0.8.20;
    // This interface is designed to be compatible with the Vyper version.
    /// @notice This is the Ethereum 2.0 deposit contract interface.
    /// For more information see the Phase 0 specification under https://github.com/ethereum/eth2.0-specs
    interface IDepositContract {
        /// @notice A processed deposit event.
        event DepositEvent(bytes pubkey, bytes withdrawal_credentials, bytes amount, bytes signature, bytes index);
        /// @notice Submit a Phase 0 DepositData object.
        /// @param pubkey A BLS12-381 public key.
        /// @param withdrawal_credentials Commitment to a public key for withdrawals.
        /// @param signature A BLS12-381 signature.
        /// @param deposit_data_root The SHA-256 hash of the SSZ-encoded DepositData object.
        /// Used as a protection against malformed input.
        function deposit(
            bytes calldata pubkey,
            bytes calldata withdrawal_credentials,
            bytes calldata signature,
            bytes32 deposit_data_root
        ) external payable;
        /// @notice Query the current deposit root hash.
        /// @return The deposit root hash.
        function get_deposit_root() external view returns (bytes32);
        /// @notice Query the current deposit count.
        /// @return The deposit count encoded as a little endian 64-bit number.
        function get_deposit_count() external view returns (bytes memory);
    }
    // Based on official specification in https://eips.ethereum.org/EIPS/eip-165
    interface ERC165 {
        /// @notice Query if a contract implements an interface
        /// @param interfaceId The interface identifier, as specified in ERC-165
        /// @dev Interface identification is specified in ERC-165. This function
        ///  uses less than 30,000 gas.
        /// @return `true` if the contract implements `interfaceId` and
        ///  `interfaceId` is not 0xffffffff, `false` otherwise
        function supportsInterface(bytes4 interfaceId) external pure returns (bool);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.20;
    /// @notice The records stored by the oracle contract informing the protocol about consensus layer activity. It is
    /// computed and reported by off-chain oracle services.
    /// @dev "current" quantities refer to the state at the `updateEndBlock` block number.
    /// @dev "cumulative" quantities refer to sums up to the `updateEndBlock` block number.
    /// @dev "window" quantities refer to sums over the block window between the `updateStartBlock` and `updateEndBlock`.
    /// @param updateStartBlock The start of the oracle record block window. This should be 1 higher than the
    /// updateEndBlock of the previous oracle record.
    /// @param updateEndBlock The block number up to which this oracle record was computed (inclusive).
    /// @param currentNumValidatorsNotWithdrawable The number of our validators that do not have the withdrawable status.
    /// @param cumulativeNumValidatorsWithdrawable The total number of our validators that have the withdrawable status.
    /// These validators have either the status `withdrawal_possible` or `withdrawal_done`. Note: validators can
    /// fluctuate between the two statuses due to top ups.
    /// @param windowWithdrawnPrincipalAmount The amount of principal that has been withdrawn from the consensus layer in
    /// the analyzed block window.
    /// @param windowWithdrawnRewardAmount The amount of rewards that has been withdrawn from the consensus layer in the
    /// analysed block window.
    /// @param currentTotalValidatorBalance The total amount of ETH in the consensus layer (i.e. the sum of all validator
    /// balances). This is one of the major quantities to compute the total value controlled by the protocol.
    /// @param cumulativeProcessedDepositAmount The total amount of ETH that has been deposited into and processed by the
    /// consensus layer. This is used to prevent double counting of the ETH deposited to the consensus layer.
    struct OracleRecord {
        uint64 updateStartBlock;
        uint64 updateEndBlock;
        uint64 currentNumValidatorsNotWithdrawable;
        uint64 cumulativeNumValidatorsWithdrawable;
        uint128 windowWithdrawnPrincipalAmount;
        uint128 windowWithdrawnRewardAmount;
        uint128 currentTotalValidatorBalance;
        uint128 cumulativeProcessedDepositAmount;
    }
    interface IOracleWrite {
        /// @notice Pushes a new record to the oracle.
        function receiveRecord(OracleRecord calldata record) external;
    }
    interface IOracleReadRecord {
        /// @notice Returns the latest validated record.
        /// @return `OracleRecord` The latest validated record.
        function latestRecord() external view returns (OracleRecord calldata);
        /// @notice Returns the record at the given index.
        /// @param idx The index of the record to retrieve.
        /// @return `OracleRecord` The record at the given index.
        function recordAt(uint256 idx) external view returns (OracleRecord calldata);
        /// @notice Returns the number of records in the oracle.
        /// @return `uint256` The number of records in the oracle.
        function numRecords() external view returns (uint256);
    }
    interface IOracleReadPending {
        /// @notice Returns the pending update.
        /// @return `OracleRecord` The pending update.
        function pendingUpdate() external view returns (OracleRecord calldata);
        /// @notice Indicates whether an oracle update is pending, i.e. if it was rejected by `_sanityCheckUpdate`.
        function hasPendingUpdate() external view returns (bool);
    }
    interface IOracleRead is IOracleReadRecord, IOracleReadPending {}
    interface IOracleManager {
        /// @notice Sets the new oracle updater for the contract.
        /// @param newUpdater The new oracle updater.
        function setOracleUpdater(address newUpdater) external;
    }
    interface IOracle is IOracleWrite, IOracleRead, IOracleManager {}
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.20;
    interface IPauserRead {
        /// @notice Flag indicating if staking is paused.
        function isStakingPaused() external view returns (bool);
        /// @notice Flag indicating if unstake requests are paused.
        function isUnstakeRequestsAndClaimsPaused() external view returns (bool);
        /// @notice Flag indicating if initiate validators is paused
        function isInitiateValidatorsPaused() external view returns (bool);
        /// @notice Flag indicating if submit oracle records is paused.
        function isSubmitOracleRecordsPaused() external view returns (bool);
        /// @notice Flag indicating if allocate ETH is paused.
        function isAllocateETHPaused() external view returns (bool);
    }
    interface IPauserWrite {
        /// @notice Pauses all actions.
        function pauseAll() external;
    }
    interface IPauser is IPauserRead, IPauserWrite {}
    // 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 MathUpgradeable {
        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 SignedMathUpgradeable {
        /**
         * @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 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);
    }
    // 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 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);
    }