Cryo Explorer Ethereum Mainnet

pragma solidity ^0.8.16;

import {Address} from "openzeppelin-contracts/contracts/utils/Address.sol";
import {Strings} from "openzeppelin-contracts/contracts/utils/Strings.sol";
import {ENS} from "ens-contracts/registry/ENS.sol";
import {IAddrResolver} from "ens-contracts/resolvers/profiles/IAddrResolver.sol";
import {INameResolver} from "ens-contracts/resolvers/profiles/INameResolver.sol";

contract ENSHelper {
    using Address for address;
    using ENSNamehash for bytes;

    // Same address for Mainet, Ropsten, Rinkerby, Gorli and other networks;
    address constant ensRegistryAddr = 0x00000000000C2E074eC69A0dFb2997BA6C7d2e1e;

    /// The namehash of the `eth` TLD in the ENS registry, eg. namehash("eth").
    bytes32 public constant ETH_NODE = keccak256(abi.encodePacked(bytes32(0), keccak256("eth")));

    /// @notice Returns the ENS name for a given address, or an string address if no name is set.
    /// @param _addr The address to lookup.
    /// @return name The ENS name for the given address.
    /// @dev For this to successfully retrieve a name, the address must have the reverse record
    ///     set, and the forward record must match the address.
    function getName(address _addr) public view returns (string memory name) {
        if (!ensRegistryAddr.isContract()) {
            return Strings.toHexString(_addr);
        }

        // Use reverse resolver to get the ENS name that address this has.
        bytes32 nodeReverse = reverseNode(_addr);
        address reverseResolverAddr = ENS(ensRegistryAddr).resolver(nodeReverse);
        if (reverseResolverAddr == address(0) || !reverseResolverAddr.isContract()) {
            return Strings.toHexString(_addr);
        }

        name = INameResolver(reverseResolverAddr).name(nodeReverse);
        if (bytes(name).length == 0) {
            return Strings.toHexString(_addr);
        }

        // ENS does not enforce the accuracy of reverse records, so you you must always perform a
        // forward resolution for the returned name and check it matches the original address.
        bytes32 nodeForward = bytes(name).namehash(0);
        address forwardResolverAddr = ENS(ensRegistryAddr).resolver(nodeForward);
        if (forwardResolverAddr == address(0) || !forwardResolverAddr.isContract()) {
            return Strings.toHexString(_addr);
        }

        address forwardAddr = IAddrResolver(forwardResolverAddr).addr(nodeForward);
        if (forwardAddr == _addr) {
            return name;
        } else {
            return Strings.toHexString(_addr);
        }
    }

    // Below are helper functions from ReverseRecords.sol, used so it's not necassary to maintain
    // a reference to the contract on each chain.
    // Source: https://github.com/ensdomains/reverse-records/blob/6ef80ba0a445b3f7cdff7819aaad1efbd8ad22fb/contracts/ReverseRecords.sol

    /// @notice This is the equivalant of namehash('addr.reverse')
    bytes32 public constant ADDR_REVERSE_NODE = 0x91d1777781884d03a6757a803996e38de2a42967fb37eeaca72729271025a9e2;

    /// @notice Returns the node hash for a given account's reverse records.
    function reverseNode(address _addr) public pure returns (bytes32) {
        return keccak256(abi.encodePacked(ADDR_REVERSE_NODE, sha3HexAddress(_addr)));
    }

    function sha3HexAddress(address addr) private pure returns (bytes32 ret) {
        addr;
        ret; // Stop warning us about unused variables
        assembly {
            let lookup := 0x3031323334353637383961626364656600000000000000000000000000000000

            for { let i := 40 } gt(i, 0) {} {
                i := sub(i, 1)
                mstore8(i, byte(and(addr, 0xf), lookup))
                addr := div(addr, 0x10)
                i := sub(i, 1)
                mstore8(i, byte(and(addr, 0xf), lookup))
                addr := div(addr, 0x10)
            }

            ret := keccak256(0, 40)
        }
    }
}

/// @dev Source: https://github.com/JonahGroendal/ens-namehash/blob/d956b0be0ae5d14191067ed398c4454e35f4558d/contracts/ENSNamehash.sol
library ENSNamehash {
    function namehash(bytes memory domain) internal pure returns (bytes32) {
        return namehash(domain, 0);
    }

    function namehash(bytes memory domain, uint256 i) internal pure returns (bytes32) {
        if (domain.length <= i) {
            return 0x0000000000000000000000000000000000000000000000000000000000000000;
        }

        uint256 len = LabelLength(domain, i);

        return keccak256(abi.encodePacked(namehash(domain, i + len + 1), keccak(domain, i, len)));
    }

    function LabelLength(bytes memory domain, uint256 i) private pure returns (uint256) {
        uint256 len;
        while (i + len != domain.length && domain[i + len] != 0x2e) {
            len++;
        }
        return len;
    }

    function keccak(bytes memory data, uint256 offset, uint256 len) private pure returns (bytes32 ret) {
        require(offset + len <= data.length);
        assembly {
            ret := keccak256(add(add(data, 32), offset), len)
        }
    }
}

// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.8.16;

import {FeeCollector} from "contracts/src/utils/FeeCollector.sol";
import {ENSHelper} from "contracts/src/utils/ENSHelper.sol";
import {StringHelper} from "contracts/src/utils/StringHelper.sol";
import {ITelepathyRouter} from "telepathy-contracts/amb/interfaces/ITelepathy.sol";
import {TelepathyHandler} from "telepathy-contracts/amb/interfaces/TelepathyHandler.sol";

/// @title CrossChainMailer
/// @author Succinct Labs
/// @notice An example contract for sending messages to other chains, using the TelepathyRouter.
/// @dev The FeeCollector is for discouraging spam on non-mainnet chains.
contract CrossChainMailer is FeeCollector, ENSHelper {
    /// @notice The TelepathyRouter contract, which sends messages to other chains.
    ITelepathyRouter public telepathyRouter;

    constructor(address _telepathyRouter) {
        telepathyRouter = ITelepathyRouter(_telepathyRouter);
    }

    /// @notice Sends a message to a destination mailbox.
    /// @param _destinationChainId The chain ID where the destination CrossChainMailbox.
    /// @param _destinationMailbox The address of the destination CrossChainMailbox.
    /// @param _message The message to send.
    function sendMail(uint32 _destinationChainId, address _destinationMailbox, bytes memory _message)
        external
        payable
    {
        if (msg.value < fee) {
            revert InsufficientFee(msg.value, fee);
        }
        string memory data = StringHelper.formatMessage(_message, msg.sender.balance, ENSHelper.getName(msg.sender));
        telepathyRouter.send(_destinationChainId, _destinationMailbox, bytes(data));
    }
}

/// @title CrossChainMailbox
/// @author Succinct Labs
/// @notice An example contract for receiving messages from other chains, using the TelepathyHandler.
contract CrossChainMailbox is TelepathyHandler {
    string[] public messages;

    event MessageReceived(uint32 indexed sourceChainId, address indexed sourceAddress, string message);

    constructor(address _telepathyRouter) TelepathyHandler(_telepathyRouter) {}

    function handleTelepathyImpl(uint32 _sourceChainId, address _sourceAddress, bytes memory _message)
        internal
        override
    {
        messages.push(string(_message));
        emit MessageReceived(_sourceChainId, _sourceAddress, string(_message));
    }

    function messagesLength() external view returns (uint256) {
        return messages.length;
    }
}

pragma solidity ^0.8.16;

import {Ownable} from "openzeppelin-contracts/contracts/access/Ownable.sol";

contract FeeCollector is Ownable {
    error InsufficientFee(uint256 actual, uint256 expected);

    /// @notice The fee to pay for sending a message.
    /// @dev The intention is only set to non-zero when deployed non-mainnet chains, used to discourage spam.
    uint256 public fee;

    /// @notice Allows owner to set a new fee.
    /// @param _fee The new fee to use.
    function setFee(uint256 _fee) external onlyOwner {
        fee = _fee;
    }

    /// @notice Allows owner to claim all fees sent to this contract.
    function claimFees() external onlyOwner {
        payable(owner()).transfer(address(this).balance);
    }
}

pragma solidity ^0.8.16;

import {Strings} from "openzeppelin-contracts/contracts/utils/Strings.sol";

library StringHelper {
    /// @notice Concatenates together a formatted message.
    /// @param _rawMessage The raw message bytes.
    /// @param _balance The balance of the sender.
    /// @param _ensName The ENS name of the sender ("" if none).
    /// @dev The formatting is like:
    ///
    ///     'hello, world!'
    ///     - alice.eth (1.00 ETH)
    function formatMessage(bytes memory _rawMessage, uint256 _balance, string memory _ensName)
        internal
        view
        returns (string memory)
    {
        string memory messageStr = string(_rawMessage);
        string memory ethBalanceStr = formatBalance(_balance);

        // Use the ENS name if it exists, otherwise use the address.
        string memory senderStr;
        if (bytes(_ensName).length == 0) {
            senderStr = Strings.toHexString(msg.sender);
        } else {
            senderStr = _ensName;
        }

        string memory lineOne = string.concat(string.concat("'", messageStr), "'\n");
        string memory lineTwo =
            string.concat(string.concat(string.concat(string.concat("- ", senderStr), " ("), ethBalanceStr), ")");
        string memory data = string.concat(lineOne, lineTwo);
        return data;
    }

    /// @notice Formats a native balance to a string with 2 decimal places and native currency
    ///     symbol. For example, 123456789000000000000 wei would be formatted as "123.46 ETH".
    /// @param _balance The balance to format.
    function formatBalance(uint256 _balance) public view returns (string memory) {
        uint256 integerAmount = _balance / 1 ether;
        uint256 integerDigits;
        if (integerAmount > 0) {
            while (true) {
                if (integerAmount >= 10 ** integerDigits) {
                    integerDigits++;
                } else {
                    break;
                }
            }
        } else {
            integerDigits = 1;
        }

        bytes memory balanceByteArr = new bytes(integerDigits + 3); // extra 3 for "." plus 2 digits
        uint256 i = integerDigits;
        while (i > 0) {
            balanceByteArr[i - 1] = bytes1(uint8(48 + integerAmount % 10));
            integerAmount /= 10;
            i--;
        }

        balanceByteArr[integerDigits] = ".";
        balanceByteArr[integerDigits + 1] = bytes1(uint8(48 + (_balance / 1e17) % 10));
        balanceByteArr[integerDigits + 2] = bytes1(uint8(48 + (_balance / 1e16) % 10));
        string memory balanceStr = string(balanceByteArr);

        // ETH for mainnet, xDAI for Gnosis, etc
        string memory currencyStr;
        if (block.chainid == 5) {
            currencyStr = " gETH";
        } else if (block.chainid == 100) {
            currencyStr = " xDAI";
        } else if (block.chainid == 137) {
            currencyStr = " MATIC";
        } else {
            currencyStr = " ETH";
        }

        return string.concat(balanceStr, currencyStr);
    }
}

pragma solidity >=0.8.4;

interface ENS {
    // Logged when the owner of a node assigns a new owner to a subnode.
    event NewOwner(bytes32 indexed node, bytes32 indexed label, address owner);

    // Logged when the owner of a node transfers ownership to a new account.
    event Transfer(bytes32 indexed node, address owner);

    // Logged when the resolver for a node changes.
    event NewResolver(bytes32 indexed node, address resolver);

    // Logged when the TTL of a node changes
    event NewTTL(bytes32 indexed node, uint64 ttl);

    // Logged when an operator is added or removed.
    event ApprovalForAll(
        address indexed owner,
        address indexed operator,
        bool approved
    );

    function setRecord(
        bytes32 node,
        address owner,
        address resolver,
        uint64 ttl
    ) external;

    function setSubnodeRecord(
        bytes32 node,
        bytes32 label,
        address owner,
        address resolver,
        uint64 ttl
    ) external;

    function setSubnodeOwner(
        bytes32 node,
        bytes32 label,
        address owner
    ) external returns (bytes32);

    function setResolver(bytes32 node, address resolver) external;

    function setOwner(bytes32 node, address owner) external;

    function setTTL(bytes32 node, uint64 ttl) external;

    function setApprovalForAll(address operator, bool approved) external;

    function owner(bytes32 node) external view returns (address);

    function resolver(bytes32 node) external view returns (address);

    function ttl(bytes32 node) external view returns (uint64);

    function recordExists(bytes32 node) external view returns (bool);

    function isApprovedForAll(
        address owner,
        address operator
    ) external view returns (bool);
}

pragma solidity ^0.8.0;

enum MessageStatus {
    NOT_EXECUTED,
    EXECUTION_FAILED,
    EXECUTION_SUCCEEDED
}

struct Message {
    uint8 version;
    uint64 nonce;
    uint32 sourceChainId;
    address senderAddress;
    uint32 recipientChainId;
    bytes32 recipientAddress;
    bytes data;
}

interface ITelepathyRouter {
    event SentMessage(uint64 indexed nonce, bytes32 indexed msgHash, bytes message);

    function send(uint32 recipientChainId, bytes32 recipientAddress, bytes calldata data)
        external
        returns (bytes32);

    function send(uint32 recipientChainId, address recipientAddress, bytes calldata data)
        external
        returns (bytes32);

    function sendViaStorage(uint32 recipientChainId, bytes32 recipientAddress, bytes calldata data)
        external
        returns (bytes32);

    function sendViaStorage(uint32 recipientChainId, address recipientAddress, bytes calldata data)
        external
        returns (bytes32);
}

interface ITelepathyReceiver {
    event ExecutedMessage(
        uint32 indexed sourceChainId,
        uint64 indexed nonce,
        bytes32 indexed msgHash,
        bytes message,
        bool status
    );

    function executeMessage(
        uint64 slot,
        bytes calldata message,
        bytes[] calldata accountProof,
        bytes[] calldata storageProof
    ) external;

    function executeMessageFromLog(
        bytes calldata srcSlotTxSlotPack,
        bytes calldata messageBytes,
        bytes32[] calldata receiptsRootProof,
        bytes32 receiptsRoot,
        bytes[] calldata receiptProof, // receipt proof against receipt root
        bytes memory txIndexRLPEncoded,
        uint256 logIndex
    ) external;
}

interface ITelepathyHandler {
    function handleTelepathy(uint32 _sourceChainId, address _senderAddress, bytes memory _data)
        external
        returns (bytes4);
}

pragma solidity ^0.8.0;

import {ITelepathyHandler} from "./ITelepathy.sol";

abstract contract TelepathyHandler is ITelepathyHandler {
    error NotFromTelepathyReceiever(address sender);

    address private _telepathyReceiever;

    constructor(address telepathyReceiever) {
        _telepathyReceiever = telepathyReceiever;
    }

    function handleTelepathy(uint32 _sourceChainId, address _senderAddress, bytes memory _data)
        external
        override
        returns (bytes4)
    {
        if (msg.sender != _telepathyReceiever) {
            revert NotFromTelepathyReceiever(msg.sender);
        }
        handleTelepathyImpl(_sourceChainId, _senderAddress, _data);
        return ITelepathyHandler.handleTelepathy.selector;
    }

    function handleTelepathyImpl(uint32 _sourceChainId, address _senderAddress, bytes memory _data)
        internal
        virtual;
}

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.4;

/**
 * Interface for the legacy (ETH-only) addr function.
 */
interface IAddrResolver {
    event AddrChanged(bytes32 indexed node, address a);

    /**
     * Returns the address associated with an ENS node.
     * @param node The ENS node to query.
     * @return The associated address.
     */
    function addr(bytes32 node) external view returns (address payable);
}

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.4;

interface INameResolver {
    event NameChanged(bytes32 indexed node, string name);

    /**
     * Returns the name associated with an ENS node, for reverse records.
     * Defined in EIP181.
     * @param node The ENS node to query.
     * @return The associated name.
     */
    function name(bytes32 node) external view returns (string memory);
}

// 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
     * ====
     *
     * [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/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

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

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

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

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

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

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

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

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

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

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

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

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

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

pragma solidity ^0.8.0;

/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

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

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

pragma solidity ^0.8.0;

import "./math/Math.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 `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);
    }
}

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

pragma solidity ^0.8.0;

import "../utils/Context.sol";

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

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

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _transferOwnership(_msgSender());
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        _checkOwner();
        _;
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

// 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) {
                return prod0 / denominator;
            }

            // Make sure the result is less than 2^256. Also prevents denominator == 0.
            require(denominator > prod1);

            ///////////////////////////////////////////////
            // 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 10, 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);
        }
    }
}