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

pragma solidity ^0.8.0;

/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.

    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;

    uint256 private _status;

    constructor() {
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and making it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        _nonReentrantBefore();
        _;
        _nonReentrantAfter();
    }

    function _nonReentrantBefore() private {
        // On the first call to nonReentrant, _status will be _NOT_ENTERED
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;
    }

    function _nonReentrantAfter() private {
        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
     * `nonReentrant` function in the call stack.
     */
    function _reentrancyGuardEntered() internal view returns (bool) {
        return _status == _ENTERED;
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC721/IERC721.sol)

pragma solidity ^0.8.0;

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

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

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

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

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

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

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

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

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

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

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

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

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

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

pragma solidity ^0.8.0;

import "./IERC165.sol";

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

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)

pragma solidity ^0.8.0;

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

// SPDX-License-Identifier: Unlicense
/*
 * @title Solidity Bytes Arrays Utils
 * @author Gonçalo Sá <[email protected]>
 *
 * @dev Bytes tightly packed arrays utility library for ethereum contracts written in Solidity.
 *      The library lets you concatenate, slice and type cast bytes arrays both in memory and storage.
 */
pragma solidity >=0.8.0 <0.9.0;

library BytesLib {
    function concat(bytes memory _preBytes, bytes memory _postBytes) internal pure returns (bytes memory) {
        bytes memory tempBytes;

        assembly {
            // Get a location of some free memory and store it in tempBytes as
            // Solidity does for memory variables.
            tempBytes := mload(0x40)

            // Store the length of the first bytes array at the beginning of
            // the memory for tempBytes.
            let length := mload(_preBytes)
            mstore(tempBytes, length)

            // Maintain a memory counter for the current write location in the
            // temp bytes array by adding the 32 bytes for the array length to
            // the starting location.
            let mc := add(tempBytes, 0x20)
            // Stop copying when the memory counter reaches the length of the
            // first bytes array.
            let end := add(mc, length)

            for {
                // Initialize a copy counter to the start of the _preBytes data,
                // 32 bytes into its memory.
                let cc := add(_preBytes, 0x20)
            } lt(mc, end) {
                // Increase both counters by 32 bytes each iteration.
                mc := add(mc, 0x20)
                cc := add(cc, 0x20)
            } {
                // Write the _preBytes data into the tempBytes memory 32 bytes
                // at a time.
                mstore(mc, mload(cc))
            }

            // Add the length of _postBytes to the current length of tempBytes
            // and store it as the new length in the first 32 bytes of the
            // tempBytes memory.
            length := mload(_postBytes)
            mstore(tempBytes, add(length, mload(tempBytes)))

            // Move the memory counter back from a multiple of 0x20 to the
            // actual end of the _preBytes data.
            mc := end
            // Stop copying when the memory counter reaches the new combined
            // length of the arrays.
            end := add(mc, length)

            for {
                let cc := add(_postBytes, 0x20)
            } lt(mc, end) {
                mc := add(mc, 0x20)
                cc := add(cc, 0x20)
            } {
                mstore(mc, mload(cc))
            }

            // Update the free-memory pointer by padding our last write location
            // to 32 bytes: add 31 bytes to the end of tempBytes to move to the
            // next 32 byte block, then round down to the nearest multiple of
            // 32. If the sum of the length of the two arrays is zero then add
            // one before rounding down to leave a blank 32 bytes (the length block with 0).
            mstore(
                0x40,
                and(
                    add(add(end, iszero(add(length, mload(_preBytes)))), 31),
                    not(31) // Round down to the nearest 32 bytes.
                )
            )
        }

        return tempBytes;
    }

    function concatStorage(bytes storage _preBytes, bytes memory _postBytes) internal {
        assembly {
            // Read the first 32 bytes of _preBytes storage, which is the length
            // of the array. (We don't need to use the offset into the slot
            // because arrays use the entire slot.)
            let fslot := sload(_preBytes.slot)
            // Arrays of 31 bytes or less have an even value in their slot,
            // while longer arrays have an odd value. The actual length is
            // the slot divided by two for odd values, and the lowest order
            // byte divided by two for even values.
            // If the slot is even, bitwise and the slot with 255 and divide by
            // two to get the length. If the slot is odd, bitwise and the slot
            // with -1 and divide by two.
            let slength := div(and(fslot, sub(mul(0x100, iszero(and(fslot, 1))), 1)), 2)
            let mlength := mload(_postBytes)
            let newlength := add(slength, mlength)
            // slength can contain both the length and contents of the array
            // if length < 32 bytes so let's prepare for that
            // v. http://solidity.readthedocs.io/en/latest/miscellaneous.html#layout-of-state-variables-in-storage
            switch add(lt(slength, 32), lt(newlength, 32))
            case 2 {
                // Since the new array still fits in the slot, we just need to
                // update the contents of the slot.
                // uint256(bytes_storage) = uint256(bytes_storage) + uint256(bytes_memory) + new_length
                sstore(
                    _preBytes.slot,
                    // all the modifications to the slot are inside this
                    // next block
                    add(
                        // we can just add to the slot contents because the
                        // bytes we want to change are the LSBs
                        fslot,
                        add(
                            mul(
                                div(
                                    // load the bytes from memory
                                    mload(add(_postBytes, 0x20)),
                                    // zero all bytes to the right
                                    exp(0x100, sub(32, mlength))
                                ),
                                // and now shift left the number of bytes to
                                // leave space for the length in the slot
                                exp(0x100, sub(32, newlength))
                            ),
                            // increase length by the double of the memory
                            // bytes length
                            mul(mlength, 2)
                        )
                    )
                )
            }
            case 1 {
                // The stored value fits in the slot, but the combined value
                // will exceed it.
                // get the keccak hash to get the contents of the array
                mstore(0x0, _preBytes.slot)
                let sc := add(keccak256(0x0, 0x20), div(slength, 32))

                // save new length
                sstore(_preBytes.slot, add(mul(newlength, 2), 1))

                // The contents of the _postBytes array start 32 bytes into
                // the structure. Our first read should obtain the `submod`
                // bytes that can fit into the unused space in the last word
                // of the stored array. To get this, we read 32 bytes starting
                // from `submod`, so the data we read overlaps with the array
                // contents by `submod` bytes. Masking the lowest-order
                // `submod` bytes allows us to add that value directly to the
                // stored value.

                let submod := sub(32, slength)
                let mc := add(_postBytes, submod)
                let end := add(_postBytes, mlength)
                let mask := sub(exp(0x100, submod), 1)

                sstore(sc, add(and(fslot, 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff00), and(mload(mc), mask)))

                for {
                    mc := add(mc, 0x20)
                    sc := add(sc, 1)
                } lt(mc, end) {
                    sc := add(sc, 1)
                    mc := add(mc, 0x20)
                } {
                    sstore(sc, mload(mc))
                }

                mask := exp(0x100, sub(mc, end))

                sstore(sc, mul(div(mload(mc), mask), mask))
            }
            default {
                // get the keccak hash to get the contents of the array
                mstore(0x0, _preBytes.slot)
                // Start copying to the last used word of the stored array.
                let sc := add(keccak256(0x0, 0x20), div(slength, 32))

                // save new length
                sstore(_preBytes.slot, add(mul(newlength, 2), 1))

                // Copy over the first `submod` bytes of the new data as in
                // case 1 above.
                let slengthmod := mod(slength, 32)
                let mlengthmod := mod(mlength, 32)
                let submod := sub(32, slengthmod)
                let mc := add(_postBytes, submod)
                let end := add(_postBytes, mlength)
                let mask := sub(exp(0x100, submod), 1)

                sstore(sc, add(sload(sc), and(mload(mc), mask)))

                for {
                    sc := add(sc, 1)
                    mc := add(mc, 0x20)
                } lt(mc, end) {
                    sc := add(sc, 1)
                    mc := add(mc, 0x20)
                } {
                    sstore(sc, mload(mc))
                }

                mask := exp(0x100, sub(mc, end))

                sstore(sc, mul(div(mload(mc), mask), mask))
            }
        }
    }

    function slice(
        bytes memory _bytes,
        uint _start,
        uint _length
    ) internal pure returns (bytes memory) {
        require(_length + 31 >= _length, "slice_overflow");
        require(_bytes.length >= _start + _length, "slice_outOfBounds");

        bytes memory tempBytes;

        assembly {
            switch iszero(_length)
            case 0 {
                // Get a location of some free memory and store it in tempBytes as
                // Solidity does for memory variables.
                tempBytes := mload(0x40)

                // The first word of the slice result is potentially a partial
                // word read from the original array. To read it, we calculate
                // the length of that partial word and start copying that many
                // bytes into the array. The first word we copy will start with
                // data we don't care about, but the last `lengthmod` bytes will
                // land at the beginning of the contents of the new array. When
                // we're done copying, we overwrite the full first word with
                // the actual length of the slice.
                let lengthmod := and(_length, 31)

                // The multiplication in the next line is necessary
                // because when slicing multiples of 32 bytes (lengthmod == 0)
                // the following copy loop was copying the origin's length
                // and then ending prematurely not copying everything it should.
                let mc := add(add(tempBytes, lengthmod), mul(0x20, iszero(lengthmod)))
                let end := add(mc, _length)

                for {
                    // The multiplication in the next line has the same exact purpose
                    // as the one above.
                    let cc := add(add(add(_bytes, lengthmod), mul(0x20, iszero(lengthmod))), _start)
                } lt(mc, end) {
                    mc := add(mc, 0x20)
                    cc := add(cc, 0x20)
                } {
                    mstore(mc, mload(cc))
                }

                mstore(tempBytes, _length)

                //update free-memory pointer
                //allocating the array padded to 32 bytes like the compiler does now
                mstore(0x40, and(add(mc, 31), not(31)))
            }
            //if we want a zero-length slice let's just return a zero-length array
            default {
                tempBytes := mload(0x40)
                //zero out the 32 bytes slice we are about to return
                //we need to do it because Solidity does not garbage collect
                mstore(tempBytes, 0)

                mstore(0x40, add(tempBytes, 0x20))
            }
        }

        return tempBytes;
    }

    function toAddress(bytes memory _bytes, uint _start) internal pure returns (address) {
        require(_bytes.length >= _start + 20, "toAddress_outOfBounds");
        address tempAddress;

        assembly {
            tempAddress := div(mload(add(add(_bytes, 0x20), _start)), 0x1000000000000000000000000)
        }

        return tempAddress;
    }

    function toUint8(bytes memory _bytes, uint _start) internal pure returns (uint8) {
        require(_bytes.length >= _start + 1, "toUint8_outOfBounds");
        uint8 tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0x1), _start))
        }

        return tempUint;
    }

    function toUint16(bytes memory _bytes, uint _start) internal pure returns (uint16) {
        require(_bytes.length >= _start + 2, "toUint16_outOfBounds");
        uint16 tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0x2), _start))
        }

        return tempUint;
    }

    function toUint32(bytes memory _bytes, uint _start) internal pure returns (uint32) {
        require(_bytes.length >= _start + 4, "toUint32_outOfBounds");
        uint32 tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0x4), _start))
        }

        return tempUint;
    }

    function toUint64(bytes memory _bytes, uint _start) internal pure returns (uint64) {
        require(_bytes.length >= _start + 8, "toUint64_outOfBounds");
        uint64 tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0x8), _start))
        }

        return tempUint;
    }

    function toUint96(bytes memory _bytes, uint _start) internal pure returns (uint96) {
        require(_bytes.length >= _start + 12, "toUint96_outOfBounds");
        uint96 tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0xc), _start))
        }

        return tempUint;
    }

    function toUint128(bytes memory _bytes, uint _start) internal pure returns (uint128) {
        require(_bytes.length >= _start + 16, "toUint128_outOfBounds");
        uint128 tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0x10), _start))
        }

        return tempUint;
    }

    function toUint256(bytes memory _bytes, uint _start) internal pure returns (uint) {
        require(_bytes.length >= _start + 32, "toUint256_outOfBounds");
        uint tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0x20), _start))
        }

        return tempUint;
    }

    function toBytes32(bytes memory _bytes, uint _start) internal pure returns (bytes32) {
        require(_bytes.length >= _start + 32, "toBytes32_outOfBounds");
        bytes32 tempBytes32;

        assembly {
            tempBytes32 := mload(add(add(_bytes, 0x20), _start))
        }

        return tempBytes32;
    }

    function equal(bytes memory _preBytes, bytes memory _postBytes) internal pure returns (bool) {
        bool success = true;

        assembly {
            let length := mload(_preBytes)

            // if lengths don't match the arrays are not equal
            switch eq(length, mload(_postBytes))
            case 1 {
                // cb is a circuit breaker in the for loop since there's
                //  no said feature for inline assembly loops
                // cb = 1 - don't breaker
                // cb = 0 - break
                let cb := 1

                let mc := add(_preBytes, 0x20)
                let end := add(mc, length)

                for {
                    let cc := add(_postBytes, 0x20)
                    // the next line is the loop condition:
                    // while(uint256(mc < end) + cb == 2)
                } eq(add(lt(mc, end), cb), 2) {
                    mc := add(mc, 0x20)
                    cc := add(cc, 0x20)
                } {
                    // if any of these checks fails then arrays are not equal
                    if iszero(eq(mload(mc), mload(cc))) {
                        // unsuccess:
                        success := 0
                        cb := 0
                    }
                }
            }
            default {
                // unsuccess:
                success := 0
            }
        }

        return success;
    }

    function equalStorage(bytes storage _preBytes, bytes memory _postBytes) internal view returns (bool) {
        bool success = true;

        assembly {
            // we know _preBytes_offset is 0
            let fslot := sload(_preBytes.slot)
            // Decode the length of the stored array like in concatStorage().
            let slength := div(and(fslot, sub(mul(0x100, iszero(and(fslot, 1))), 1)), 2)
            let mlength := mload(_postBytes)

            // if lengths don't match the arrays are not equal
            switch eq(slength, mlength)
            case 1 {
                // slength can contain both the length and contents of the array
                // if length < 32 bytes so let's prepare for that
                // v. http://solidity.readthedocs.io/en/latest/miscellaneous.html#layout-of-state-variables-in-storage
                if iszero(iszero(slength)) {
                    switch lt(slength, 32)
                    case 1 {
                        // blank the last byte which is the length
                        fslot := mul(div(fslot, 0x100), 0x100)

                        if iszero(eq(fslot, mload(add(_postBytes, 0x20)))) {
                            // unsuccess:
                            success := 0
                        }
                    }
                    default {
                        // cb is a circuit breaker in the for loop since there's
                        //  no said feature for inline assembly loops
                        // cb = 1 - don't breaker
                        // cb = 0 - break
                        let cb := 1

                        // get the keccak hash to get the contents of the array
                        mstore(0x0, _preBytes.slot)
                        let sc := keccak256(0x0, 0x20)

                        let mc := add(_postBytes, 0x20)
                        let end := add(mc, mlength)

                        // the next line is the loop condition:
                        // while(uint256(mc < end) + cb == 2)
                        for {

                        } eq(add(lt(mc, end), cb), 2) {
                            sc := add(sc, 1)
                            mc := add(mc, 0x20)
                        } {
                            if iszero(eq(sload(sc), mload(mc))) {
                                // unsuccess:
                                success := 0
                                cb := 0
                            }
                        }
                    }
                }
            }
            default {
                // unsuccess:
                success := 0
            }
        }

        return success;
    }
}

// SPDX-License-Identifier: MIT OR Apache-2.0
pragma solidity >=0.7.6;

library ExcessivelySafeCall {
    uint constant LOW_28_MASK = 0x00000000ffffffffffffffffffffffffffffffffffffffffffffffffffffffff;

    /// @notice Use when you _really_ really _really_ don't trust the called
    /// contract. This prevents the called contract from causing reversion of
    /// the caller in as many ways as we can.
    /// @dev The main difference between this and a solidity low-level call is
    /// that we limit the number of bytes that the callee can cause to be
    /// copied to caller memory. This prevents stupid things like malicious
    /// contracts returning 10,000,000 bytes causing a local OOG when copying
    /// to memory.
    /// @param _target The address to call
    /// @param _gas The amount of gas to forward to the remote contract
    /// @param _maxCopy The maximum number of bytes of returndata to copy
    /// to memory.
    /// @param _calldata The data to send to the remote contract
    /// @return success and returndata, as `.call()`. Returndata is capped to
    /// `_maxCopy` bytes.
    function excessivelySafeCall(
        address _target,
        uint _gas,
        uint16 _maxCopy,
        bytes memory _calldata
    ) internal returns (bool, bytes memory) {
        // set up for assembly call
        uint _toCopy;
        bool _success;
        bytes memory _returnData = new bytes(_maxCopy);
        // dispatch message to recipient
        // by assembly calling "handle" function
        // we call via assembly to avoid memcopying a very large returndata
        // returned by a malicious contract
        assembly {
            _success := call(
                _gas, // gas
                _target, // recipient
                0, // ether value
                add(_calldata, 0x20), // inloc
                mload(_calldata), // inlen
                0, // outloc
                0 // outlen
            )
            // limit our copy to 256 bytes
            _toCopy := returndatasize()
            if gt(_toCopy, _maxCopy) {
                _toCopy := _maxCopy
            }
            // Store the length of the copied bytes
            mstore(_returnData, _toCopy)
            // copy the bytes from returndata[0:_toCopy]
            returndatacopy(add(_returnData, 0x20), 0, _toCopy)
        }
        return (_success, _returnData);
    }

    /// @notice Use when you _really_ really _really_ don't trust the called
    /// contract. This prevents the called contract from causing reversion of
    /// the caller in as many ways as we can.
    /// @dev The main difference between this and a solidity low-level call is
    /// that we limit the number of bytes that the callee can cause to be
    /// copied to caller memory. This prevents stupid things like malicious
    /// contracts returning 10,000,000 bytes causing a local OOG when copying
    /// to memory.
    /// @param _target The address to call
    /// @param _gas The amount of gas to forward to the remote contract
    /// @param _maxCopy The maximum number of bytes of returndata to copy
    /// to memory.
    /// @param _calldata The data to send to the remote contract
    /// @return success and returndata, as `.call()`. Returndata is capped to
    /// `_maxCopy` bytes.
    function excessivelySafeStaticCall(
        address _target,
        uint _gas,
        uint16 _maxCopy,
        bytes memory _calldata
    ) internal view returns (bool, bytes memory) {
        // set up for assembly call
        uint _toCopy;
        bool _success;
        bytes memory _returnData = new bytes(_maxCopy);
        // dispatch message to recipient
        // by assembly calling "handle" function
        // we call via assembly to avoid memcopying a very large returndata
        // returned by a malicious contract
        assembly {
            _success := staticcall(
                _gas, // gas
                _target, // recipient
                add(_calldata, 0x20), // inloc
                mload(_calldata), // inlen
                0, // outloc
                0 // outlen
            )
            // limit our copy to 256 bytes
            _toCopy := returndatasize()
            if gt(_toCopy, _maxCopy) {
                _toCopy := _maxCopy
            }
            // Store the length of the copied bytes
            mstore(_returnData, _toCopy)
            // copy the bytes from returndata[0:_toCopy]
            returndatacopy(add(_returnData, 0x20), 0, _toCopy)
        }
        return (_success, _returnData);
    }

    /**
     * @notice Swaps function selectors in encoded contract calls
     * @dev Allows reuse of encoded calldata for functions with identical
     * argument types but different names. It simply swaps out the first 4 bytes
     * for the new selector. This function modifies memory in place, and should
     * only be used with caution.
     * @param _newSelector The new 4-byte selector
     * @param _buf The encoded contract args
     */
    function swapSelector(bytes4 _newSelector, bytes memory _buf) internal pure {
        require(_buf.length >= 4);
        uint _mask = LOW_28_MASK;
        assembly {
            // load the first word of
            let _word := mload(add(_buf, 0x20))
            // mask out the top 4 bytes
            // /x
            _word := and(_word, _mask)
            _word := or(_newSelector, _word)
            mstore(add(_buf, 0x20), _word)
        }
    }
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.5.0;

import "./ILayerZeroUserApplicationConfig.sol";

interface ILayerZeroEndpoint is ILayerZeroUserApplicationConfig {
    // @notice send a LayerZero message to the specified address at a LayerZero endpoint.
    // @param _dstChainId - the destination chain identifier
    // @param _destination - the address on destination chain (in bytes). address length/format may vary by chains
    // @param _payload - a custom bytes payload to send to the destination contract
    // @param _refundAddress - if the source transaction is cheaper than the amount of value passed, refund the additional amount to this address
    // @param _zroPaymentAddress - the address of the ZRO token holder who would pay for the transaction
    // @param _adapterParams - parameters for custom functionality. e.g. receive airdropped native gas from the relayer on destination
    function send(
        uint16 _dstChainId,
        bytes calldata _destination,
        bytes calldata _payload,
        address payable _refundAddress,
        address _zroPaymentAddress,
        bytes calldata _adapterParams
    ) external payable;

    // @notice used by the messaging library to publish verified payload
    // @param _srcChainId - the source chain identifier
    // @param _srcAddress - the source contract (as bytes) at the source chain
    // @param _dstAddress - the address on destination chain
    // @param _nonce - the unbound message ordering nonce
    // @param _gasLimit - the gas limit for external contract execution
    // @param _payload - verified payload to send to the destination contract
    function receivePayload(
        uint16 _srcChainId,
        bytes calldata _srcAddress,
        address _dstAddress,
        uint64 _nonce,
        uint _gasLimit,
        bytes calldata _payload
    ) external;

    // @notice get the inboundNonce of a lzApp from a source chain which could be EVM or non-EVM chain
    // @param _srcChainId - the source chain identifier
    // @param _srcAddress - the source chain contract address
    function getInboundNonce(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (uint64);

    // @notice get the outboundNonce from this source chain which, consequently, is always an EVM
    // @param _srcAddress - the source chain contract address
    function getOutboundNonce(uint16 _dstChainId, address _srcAddress) external view returns (uint64);

    // @notice gets a quote in source native gas, for the amount that send() requires to pay for message delivery
    // @param _dstChainId - the destination chain identifier
    // @param _userApplication - the user app address on this EVM chain
    // @param _payload - the custom message to send over LayerZero
    // @param _payInZRO - if false, user app pays the protocol fee in native token
    // @param _adapterParam - parameters for the adapter service, e.g. send some dust native token to dstChain
    function estimateFees(
        uint16 _dstChainId,
        address _userApplication,
        bytes calldata _payload,
        bool _payInZRO,
        bytes calldata _adapterParam
    ) external view returns (uint nativeFee, uint zroFee);

    // @notice get this Endpoint's immutable source identifier
    function getChainId() external view returns (uint16);

    // @notice the interface to retry failed message on this Endpoint destination
    // @param _srcChainId - the source chain identifier
    // @param _srcAddress - the source chain contract address
    // @param _payload - the payload to be retried
    function retryPayload(
        uint16 _srcChainId,
        bytes calldata _srcAddress,
        bytes calldata _payload
    ) external;

    // @notice query if any STORED payload (message blocking) at the endpoint.
    // @param _srcChainId - the source chain identifier
    // @param _srcAddress - the source chain contract address
    function hasStoredPayload(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (bool);

    // @notice query if the _libraryAddress is valid for sending msgs.
    // @param _userApplication - the user app address on this EVM chain
    function getSendLibraryAddress(address _userApplication) external view returns (address);

    // @notice query if the _libraryAddress is valid for receiving msgs.
    // @param _userApplication - the user app address on this EVM chain
    function getReceiveLibraryAddress(address _userApplication) external view returns (address);

    // @notice query if the non-reentrancy guard for send() is on
    // @return true if the guard is on. false otherwise
    function isSendingPayload() external view returns (bool);

    // @notice query if the non-reentrancy guard for receive() is on
    // @return true if the guard is on. false otherwise
    function isReceivingPayload() external view returns (bool);

    // @notice get the configuration of the LayerZero messaging library of the specified version
    // @param _version - messaging library version
    // @param _chainId - the chainId for the pending config change
    // @param _userApplication - the contract address of the user application
    // @param _configType - type of configuration. every messaging library has its own convention.
    function getConfig(
        uint16 _version,
        uint16 _chainId,
        address _userApplication,
        uint _configType
    ) external view returns (bytes memory);

    // @notice get the send() LayerZero messaging library version
    // @param _userApplication - the contract address of the user application
    function getSendVersion(address _userApplication) external view returns (uint16);

    // @notice get the lzReceive() LayerZero messaging library version
    // @param _userApplication - the contract address of the user application
    function getReceiveVersion(address _userApplication) external view returns (uint16);
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.5.0;

interface ILayerZeroReceiver {
    // @notice LayerZero endpoint will invoke this function to deliver the message on the destination
    // @param _srcChainId - the source endpoint identifier
    // @param _srcAddress - the source sending contract address from the source chain
    // @param _nonce - the ordered message nonce
    // @param _payload - the signed payload is the UA bytes has encoded to be sent
    function lzReceive(
        uint16 _srcChainId,
        bytes calldata _srcAddress,
        uint64 _nonce,
        bytes calldata _payload
    ) external;
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.5.0;

interface ILayerZeroUserApplicationConfig {
    // @notice set the configuration of the LayerZero messaging library of the specified version
    // @param _version - messaging library version
    // @param _chainId - the chainId for the pending config change
    // @param _configType - type of configuration. every messaging library has its own convention.
    // @param _config - configuration in the bytes. can encode arbitrary content.
    function setConfig(
        uint16 _version,
        uint16 _chainId,
        uint _configType,
        bytes calldata _config
    ) external;

    // @notice set the send() LayerZero messaging library version to _version
    // @param _version - new messaging library version
    function setSendVersion(uint16 _version) external;

    // @notice set the lzReceive() LayerZero messaging library version to _version
    // @param _version - new messaging library version
    function setReceiveVersion(uint16 _version) external;

    // @notice Only when the UA needs to resume the message flow in blocking mode and clear the stored payload
    // @param _srcChainId - the chainId of the source chain
    // @param _srcAddress - the contract address of the source contract at the source chain
    function forceResumeReceive(uint16 _srcChainId, bytes calldata _srcAddress) external;
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "solady/src/auth/Ownable.sol";
import "./interfaces/ILayerZeroReceiver.sol";
import "./interfaces/ILayerZeroUserApplicationConfig.sol";
import "./interfaces/ILayerZeroEndpoint.sol";
import "../libraries/BytesLib.sol";

/*
 * a generic LzReceiver implementation
 */
abstract contract LzApp is Ownable, ILayerZeroReceiver, ILayerZeroUserApplicationConfig {
    using BytesLib for bytes;

    // ua can not send payload larger than this by default, but it can be changed by the ua owner
    uint public constant DEFAULT_PAYLOAD_SIZE_LIMIT = 10_000;
    uint public constant DEFAULT_MIN_GAS_LIMIT = 150_000;

    ILayerZeroEndpoint public lzEndpoint;
    mapping(uint16 => bytes) public trustedRemoteLookup;
    mapping(uint16 => mapping(uint16 => uint)) public minDstGasLookup;
    mapping(uint16 => uint) public payloadSizeLimitLookup;
    address public precrime;

    event SetPrecrime(address precrime);
    event SetTrustedRemote(uint16 _remoteChainId, bytes _path);
    event SetTrustedRemoteAddress(uint16 _remoteChainId, bytes _remoteAddress);
    event SetMinDstGas(uint16 _dstChainId, uint16 _type, uint _minDstGas);

    // Note: because we need deterministic deployments we can't use a differing constructor argument
    // So we set this after deployment once which makes it effectively immutable
    function setLzEndpoint(address _lzEndpoint) external onlyOwner {
        require(address(lzEndpoint) == address(0), "LzApp: lzEndpoint already set");
        lzEndpoint = ILayerZeroEndpoint(_lzEndpoint);
    }

    function lzReceive(
        uint16 _srcChainId,
        bytes calldata _srcAddress,
        uint64 _nonce,
        bytes calldata _payload
    ) public virtual override {
        // lzReceive must be called by the endpoint for security
        require(msg.sender == address(lzEndpoint), "LzApp: invalid endpoint caller");

        bytes memory trustedRemote = trustedRemoteLookup[_srcChainId];
        // if will still block the message pathway from (srcChainId, srcAddress). should not receive message from untrusted remote.
        require(
            _srcAddress.length == trustedRemote.length && trustedRemote.length > 0 && keccak256(_srcAddress) == keccak256(trustedRemote),
            "LzApp: invalid source sending contract"
        );

        _blockingLzReceive(_srcChainId, _srcAddress, _nonce, _payload);
    }

    // abstract function - the default behaviour of LayerZero is blocking. See: NonblockingLzApp if you dont need to enforce ordered messaging
    function _blockingLzReceive(
        uint16 _srcChainId,
        bytes memory _srcAddress,
        uint64 _nonce,
        bytes memory _payload
    ) internal virtual;

    function _lzSend(
        uint16 _dstChainId,
        bytes memory _payload,
        address payable _refundAddress,
        address _zroPaymentAddress,
        bytes memory _adapterParams,
        uint _nativeFee
    ) internal virtual {
        bytes memory trustedRemote = trustedRemoteLookup[_dstChainId];
        require(trustedRemote.length != 0, "LzApp: destination chain is not a trusted source");
        _checkPayloadSize(_dstChainId, _payload.length);
        lzEndpoint.send{value: _nativeFee}(_dstChainId, trustedRemote, _payload, _refundAddress, _zroPaymentAddress, _adapterParams);
    }

    function _checkGasLimit(
        uint16 _dstChainId,
        uint16 _type,
        bytes memory _adapterParams,
        uint _extraGas
    ) internal view virtual {
        uint providedGasLimit = _getGasLimit(_adapterParams);
        uint minGasLimit = minDstGasLookup[_dstChainId][_type];
        if (minGasLimit == 0) {
            // use default if not set
            minGasLimit = DEFAULT_MIN_GAS_LIMIT;
        }
        require(minGasLimit > 0, "LzApp: minGasLimit not set");
        require(providedGasLimit >= minGasLimit + _extraGas, "LzApp: gas limit is too low");
    }

    function _getGasLimit(bytes memory _adapterParams) internal pure virtual returns (uint gasLimit) {
        require(_adapterParams.length >= 34, "LzApp: invalid adapterParams");
        assembly {
            gasLimit := mload(add(_adapterParams, 34))
        }
    }

    function _checkPayloadSize(uint16 _dstChainId, uint _payloadSize) internal view virtual {
        uint payloadSizeLimit = payloadSizeLimitLookup[_dstChainId];
        if (payloadSizeLimit == 0) {
            // use default if not set
            payloadSizeLimit = DEFAULT_PAYLOAD_SIZE_LIMIT;
        }
        require(_payloadSize <= payloadSizeLimit, "LzApp: payload size is too large");
    }

    //---------------------------UserApplication config----------------------------------------
    function getConfig(
        uint16 _version,
        uint16 _chainId,
        address,
        uint _configType
    ) external view returns (bytes memory) {
        return lzEndpoint.getConfig(_version, _chainId, address(this), _configType);
    }

    // generic config for LayerZero user Application
    function setConfig(
        uint16 _version,
        uint16 _chainId,
        uint _configType,
        bytes calldata _config
    ) external override onlyOwner {
        lzEndpoint.setConfig(_version, _chainId, _configType, _config);
    }

    function setSendVersion(uint16 _version) external override onlyOwner {
        lzEndpoint.setSendVersion(_version);
    }

    function setReceiveVersion(uint16 _version) external override onlyOwner {
        lzEndpoint.setReceiveVersion(_version);
    }

    function forceResumeReceive(uint16 _srcChainId, bytes calldata _srcAddress) external override onlyOwner {
        lzEndpoint.forceResumeReceive(_srcChainId, _srcAddress);
    }

    // _path = abi.encodePacked(remoteAddress, localAddress)
    // this function set the trusted path for the cross-chain communication
    function setTrustedRemote(uint16 _remoteChainId, bytes calldata _path) external onlyOwner {
        trustedRemoteLookup[_remoteChainId] = _path;
        // emit SetTrustedRemote(_remoteChainId, _path);
    }

    function setTrustedRemoteAddress(uint16 _remoteChainId, bytes calldata _remoteAddress) external onlyOwner {
        trustedRemoteLookup[_remoteChainId] = abi.encodePacked(_remoteAddress, address(this));
        // emit SetTrustedRemoteAddress(_remoteChainId, _remoteAddress);
    }


    function batchSetTrustedRemote(uint16[] calldata _remoteChainIds, bytes[] calldata _paths) external onlyOwner {
        require(_remoteChainIds.length == _paths.length, "LzApp: invalid input length");
        for (uint i = 0; i < _remoteChainIds.length; i++) {
            trustedRemoteLookup[_remoteChainIds[i]] = _paths[i];
            // emit SetTrustedRemote(_remoteChainIds[i], _paths[i]);
        }
    }

    function batchSetTrustedRemoteAddress(uint16[] calldata _remoteChainIds, bytes[] calldata _remoteAddresses) external onlyOwner {
        require(_remoteChainIds.length == _remoteAddresses.length, "LzApp: invalid input length");
        for (uint i = 0; i < _remoteChainIds.length; i++) {
            trustedRemoteLookup[_remoteChainIds[i]] = abi.encodePacked(_remoteAddresses[i], address(this));
            // emit SetTrustedRemoteAddress(_remoteChainIds[i], _remoteAddresses[i]);
        }
    }

    function getTrustedRemoteAddress(uint16 _remoteChainId) external view returns (bytes memory) {
        bytes memory path = trustedRemoteLookup[_remoteChainId];
        require(path.length != 0, "LzApp: no trusted path record");
        return path.slice(0, path.length - 20); // the last 20 bytes should be address(this)
    }

    function setPrecrime(address _precrime) external onlyOwner {
        precrime = _precrime;
        emit SetPrecrime(_precrime);
    }

    function setMinDstGas(
        uint16 _dstChainId,
        uint16 _packetType,
        uint _minGas
    ) external onlyOwner {
        minDstGasLookup[_dstChainId][_packetType] = _minGas;
        // emit SetMinDstGas(_dstChainId, _packetType, _minGas);
    }

    // if the size is 0, it means default size limit
    function setPayloadSizeLimit(uint16 _dstChainId, uint _size) external onlyOwner {
        payloadSizeLimitLookup[_dstChainId] = _size;
    }

    //--------------------------- VIEW FUNCTION ----------------------------------------
    function isTrustedRemote(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (bool) {
        bytes memory trustedSource = trustedRemoteLookup[_srcChainId];
        return keccak256(trustedSource) == keccak256(_srcAddress);
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./LzApp.sol";
import "../libraries/ExcessivelySafeCall.sol";

/*
 * the default LayerZero messaging behaviour is blocking, i.e. any failed message will block the channel
 * this abstract class try-catch all fail messages and store locally for future retry. hence, non-blocking
 * NOTE: if the srcAddress is not configured properly, it will still block the message pathway from (srcChainId, srcAddress)
 */
abstract contract NonblockingLzApp is LzApp {
    using ExcessivelySafeCall for address;

    constructor() LzApp() {}

    mapping(uint16 => mapping(bytes => mapping(uint64 => bytes32))) public failedMessages;

    event MessageFailed(uint16 _srcChainId, bytes _srcAddress, uint64 _nonce, bytes _payload, bytes _reason);
    event RetryMessageSuccess(uint16 _srcChainId, bytes _srcAddress, uint64 _nonce, bytes32 _payloadHash);

    // overriding the virtual function in LzReceiver
    function _blockingLzReceive(
        uint16 _srcChainId,
        bytes memory _srcAddress,
        uint64 _nonce,
        bytes memory _payload
    ) internal virtual override {
        (bool success, bytes memory reason) = address(this).excessivelySafeCall(
            gasleft(),
            150,
            abi.encodeWithSelector(this.nonblockingLzReceive.selector, _srcChainId, _srcAddress, _nonce, _payload)
        );
        if (!success) {
            _storeFailedMessage(_srcChainId, _srcAddress, _nonce, _payload, reason);
        }
    }

    function _storeFailedMessage(
        uint16 _srcChainId,
        bytes memory _srcAddress,
        uint64 _nonce,
        bytes memory _payload,
        bytes memory _reason
    ) internal virtual {
        failedMessages[_srcChainId][_srcAddress][_nonce] = keccak256(_payload);
        emit MessageFailed(_srcChainId, _srcAddress, _nonce, _payload, _reason);
    }

    function nonblockingLzReceive(
        uint16 _srcChainId,
        bytes calldata _srcAddress,
        uint64 _nonce,
        bytes calldata _payload
    ) public virtual {
        // only internal transaction
        require(msg.sender == address(this), "NonblockingLzApp: caller must be LzApp");
        _nonblockingLzReceive(_srcChainId, _srcAddress, _nonce, _payload);
    }

    //@notice override this function
    function _nonblockingLzReceive(
        uint16 _srcChainId,
        bytes memory _srcAddress,
        uint64 _nonce,
        bytes memory _payload
    ) internal virtual;

    function retryMessage(
        uint16 _srcChainId,
        bytes calldata _srcAddress,
        uint64 _nonce,
        bytes calldata _payload
    ) public payable virtual {
        // assert there is message to retry
        bytes32 payloadHash = failedMessages[_srcChainId][_srcAddress][_nonce];
        require(payloadHash != bytes32(0), "NonblockingLzApp: no stored message");
        require(keccak256(_payload) == payloadHash, "NonblockingLzApp: invalid payload");
        // clear the stored message
        failedMessages[_srcChainId][_srcAddress][_nonce] = bytes32(0);
        // execute the message. revert if it fails again
        _nonblockingLzReceive(_srcChainId, _srcAddress, _nonce, _payload);
        emit RetryMessageSuccess(_srcChainId, _srcAddress, _nonce, payloadHash);
    }
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.5.0;

import "./IONFT721Core.sol";
import "@openzeppelin/contracts/token/ERC721/IERC721.sol";

/**
 * @dev Interface of the ONFT standard
 */
interface IONFT721 is IONFT721Core/*, IERC721*/ {

}

// SPDX-License-Identifier: MIT

pragma solidity >=0.5.0;

import "@openzeppelin/contracts/utils/introspection/IERC165.sol";

/**
 * @dev Interface of the ONFT Core standard
 */
interface IONFT721Core is IERC165 {
    /**
     * @dev Emitted when `_tokenIds[]` are moved from the `_sender` to (`_dstChainId`, `_toAddress`)
     * `_nonce` is the outbound nonce from
     */
    event SendToChain(uint16 indexed _dstChainId, address indexed _from, bytes indexed _toAddress, uint[] _tokenIds);
    event ReceiveFromChain(uint16 indexed _srcChainId, bytes indexed _srcAddress, address indexed _toAddress, uint[] _tokenIds);
    event SetMinGasToTransferAndStore(uint _minGasToTransferAndStore);
    event SetDstChainIdToTransferGas(uint16 _dstChainId, uint _dstChainIdToTransferGas);
    event SetDstChainIdToBatchLimit(uint16 _dstChainId, uint _dstChainIdToBatchLimit);

    /**
     * @dev Emitted when `_payload` was received from lz, but not enough gas to deliver all tokenIds
     */
    event CreditStored(bytes32 _hashedPayload, bytes _payload);
    /**
     * @dev Emitted when `_hashedPayload` has been completely delivered
     */
    event CreditCleared(bytes32 _hashedPayload);

    /**
     * @dev send token `_tokenId` to (`_dstChainId`, `_toAddress`) from `_from`
     * `_toAddress` can be any size depending on the `dstChainId`.
     * `_zroPaymentAddress` set to address(0x0) if not paying in ZRO (LayerZero Token)
     * `_adapterParams` is a flexible bytes array to indicate messaging adapter services
     */
    function sendFrom(
        address _from,
        uint16 _dstChainId,
        bytes calldata _toAddress,
        uint _tokenId,
        address payable _refundAddress,
        address _zroPaymentAddress,
        bytes calldata _adapterParams
    ) external payable;

    /**
     * @dev send tokens `_tokenIds[]` to (`_dstChainId`, `_toAddress`) from `_from`
     * `_toAddress` can be any size depending on the `dstChainId`.
     * `_zroPaymentAddress` set to address(0x0) if not paying in ZRO (LayerZero Token)
     * `_adapterParams` is a flexible bytes array to indicate messaging adapter services
     */
    function sendBatchFrom(
        address _from,
        uint16 _dstChainId,
        bytes calldata _toAddress,
        uint[] calldata _tokenIds,
        address payable _refundAddress,
        address _zroPaymentAddress,
        bytes calldata _adapterParams
    ) external payable;

    /**
     * @dev estimate send token `_tokenId` to (`_dstChainId`, `_toAddress`)
     * _dstChainId - L0 defined chain id to send tokens too
     * _toAddress - dynamic bytes array which contains the address to whom you are sending tokens to on the dstChain
     * _tokenId - token Id to transfer
     * _useZro - indicates to use zro to pay L0 fees
     * _adapterParams - flexible bytes array to indicate messaging adapter services in L0
     */
    function estimateSendFee(
        uint16 _dstChainId,
        bytes calldata _toAddress,
        uint _tokenId,
        bool _useZro,
        bytes calldata _adapterParams
    ) external view returns (uint nativeFee, uint zroFee);

    /**
     * @dev estimate send token `_tokenId` to (`_dstChainId`, `_toAddress`)
     * _dstChainId - L0 defined chain id to send tokens too
     * _toAddress - dynamic bytes array which contains the address to whom you are sending tokens to on the dstChain
     * _tokenIds[] - token Ids to transfer
     * _useZro - indicates to use zro to pay L0 fees
     * _adapterParams - flexible bytes array to indicate messaging adapter services in L0
     */
    function estimateSendBatchFee(
        uint16 _dstChainId,
        bytes calldata _toAddress,
        uint[] calldata _tokenIds,
        bool _useZro,
        bytes calldata _adapterParams
    ) external view returns (uint nativeFee, uint zroFee);
}

// SPDX-License-Identifier: Unlicense
pragma solidity >=0.8.0;

interface IYouAreRender {
    function tokenURI(uint256 tokenId, uint256[] memory history, uint256 transfers) external pure returns (string memory);

    function renderSVG(uint256 tokenId, uint256[] memory history) external pure returns (string memory);

    function renderSVGBase64(uint256 tokenId, uint256[] memory history) external pure returns (string memory);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./YouAreONFT721Mod.sol";
import "./interfaces/IYouAreRender.sol";

////////////////////////////////////////////////////////////////////////
//                                                                    //
//                                                                    //
//                                                                    //
//                                                                    //
//                                                                    //
//                                                                    //
//                                                                    //
//                           you                                      //
//                               are                                  //
//                                   here                             //
//                                                                    //
//                                                                    //
//                                                                    //
//                                                                    //
//                                                                    //
//                                                       0xfff.eth    //
//                                                                    //
////////////////////////////////////////////////////////////////////////

contract YouAreHere is YouAreONFT721Mod {

    uint256 public price = 0.1 ether;
    uint256 public mintable = type(uint256).max; // not mintable by default
    address public claimableBy;
    bool public minted;
    bool internal artistProofMinted;
    address public renderContract;

    constructor() YouAreONFT721Mod() {
        _initializeOwner(tx.origin);
    }

    /*//////////////////////////////////////////////////////////////
                                ADMIN
    //////////////////////////////////////////////////////////////*/

    function setMintable(uint value) external onlyOwner {
        mintable = value;
    }

    function setPrice(uint256 _price) external onlyOwner {
        price = _price;
    }

    function setClaimable(address _claimableBy) external onlyOwner {
        claimableBy = _claimableBy;
    }

    function setRenderContract(address _renderContract) external onlyOwner {
        renderContract = _renderContract;
    }

    function setChainIdIndexLookup(uint256[] calldata chainIdsToSet, uint256 startIndex) external onlyOwner {
        _setChainIdIndexLookup(chainIdsToSet, startIndex);
    }

    function withdrawBalance(address _to) external onlyOwner {
        (bool success, ) = payable(_to).call{value: address(this).balance}("");
        require(success);
    }

    /*//////////////////////////////////////////////////////////////
                                MINTING
    //////////////////////////////////////////////////////////////*/

    function mintArtistProof(address _to) external onlyOwner {
        require(!artistProofMinted, "ALREADY_MINTED");
        // épreuve d'artiste / artist proof
        require(block.chainid == 1 || block.chainid == 11155111 || block.chainid == 31337, "NOT_MAINNET");
        artistProofMinted = true;
        _initHistory(0xfff);
        _initHistory(0xfff_fff);
        _initHistory(0xfff_fff_fff);
        _mint(_to, 0xfff);
        _mint(_to, 0xfff_fff);
        _mint(_to, 0xfff_fff_fff);
    }

    function emergencyRestore(address _to) external onlyOwner {
        require(minted, "NOT_MINTED");
        // only init history if it's not already initialized
        if (historyOfTokenId[block.chainid][0] == 0) {
            _initHistory(block.chainid);
        }
        _mint(_to, block.chainid);
    }

    function ownerMintTo(address _to) external onlyOwner {
        require(!minted, "ALREADY_MINTED");
        _initHistory(block.chainid);
        minted = true;
        _mint(_to, block.chainid);
    }

    function mint(address _to) external payable {
        require(!minted, "ALREADY_MINTED");
        require(mintable < block.timestamp, "NOT_MINTABLE");
        require(msg.value == price, "PRICE");
        _initHistory(block.chainid);
        minted = true;
        _mint(_to, block.chainid);
    }

    function claim() external payable {
        require(!minted, "ALREADY_MINTED");
        require(claimableBy == msg.sender, "NOT_CLAIMABLE");
        _initHistory(block.chainid);
        minted = true;
        _mint(msg.sender, block.chainid);
    }

    function burn(uint256 tokenId) external {
        require(_isApprovedOrOwner(msg.sender, tokenId), "YouAreHere: burn caller is not owner nor approved");
        _burn(tokenId);
    }

    /*//////////////////////////////////////////////////////////////
                                TRANSFERS
    //////////////////////////////////////////////////////////////*/

    function _debitFrom(address _from, uint16, bytes memory, uint _tokenId) internal virtual override {
        require(_isApprovedOrOwner(msg.sender, _tokenId), "YouAreHere: send caller is not owner nor approved");
        require(ERC721.ownerOf(_tokenId) == _from, "YouAreHere: send from incorrect owner");
        _burn(_tokenId);
    }

    function _creditTo(uint16, address _toAddress, uint _tokenId, uint256[4] memory _history, uint256 _transfers) internal virtual override {
        require(!_exists(_tokenId));
        _updateChainHistory(_tokenId, _history, _transfers);
        _mint(_toAddress, _tokenId);
    }

    /*//////////////////////////////////////////////////////////////
                                VIEW
    //////////////////////////////////////////////////////////////*/

    function name() public pure override returns (string memory) {
        return "You Are Here";
    }

    function symbol() public pure override returns (string memory) {
        return "YOUAREHERE";
    }

    function tokenURI(uint256 tokenId) public view override returns (string memory) {
        require(_exists(tokenId), "NOT_FOUND");
        return IYouAreRender(renderContract).tokenURI(tokenId, _getHistoryUnpacked(tokenId), numTransferForTokenId[tokenId]);
    }

    function renderSVG(uint256 tokenId) external view returns (string memory) {
        require(_exists(tokenId), "NOT_FOUND");
        return IYouAreRender(renderContract).renderSVG(tokenId, _getHistoryUnpacked(tokenId));
    }

    function renderSVGBase64(uint256 tokenId) external view returns (string memory) {
        require(_exists(tokenId), "NOT_FOUND");
        return IYouAreRender(renderContract).renderSVGBase64(tokenId, _getHistoryUnpacked(tokenId));
    }

    function renderSVGwithHistory(uint256 tokenId, uint256[] memory history) external view returns (string memory) {
        return IYouAreRender(renderContract).renderSVG(tokenId, history);
    }

    function renderSVGBase64withHistory(uint256 tokenId, uint256[] memory history) external view returns (string memory) {
        return IYouAreRender(renderContract).renderSVGBase64(tokenId, history);
    }

    function _getHistoriesOfExisting(uint[] memory tokenIds) internal view returns (uint256[][] memory) {
        uint256[][] memory result = new uint256[][](tokenIds.length);
        for (uint i; i < tokenIds.length; i++) {
            if (_exists(tokenIds[i])) {
                result[i] = _getHistoryUnpacked(tokenIds[i]);
            }
        }
        return result;
    }

    function tokenState(
        uint[] memory tokenIds
    ) public view returns (address[] memory _owners, uint _mintable, bool _minted, uint256 _price, address _claimableBy) {
        _owners = rawOwnersOf(tokenIds);
        _mintable = mintable;
        _minted = minted;
        _price = price;
        _claimableBy = claimableBy;
    }

}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

error YouAreHistory__ChainIndexTooLarge();

abstract contract YouAreHistory {
    uint256 public constant MAX_CHAIN_HISTORY_LENGTH = 128; // uint256[4] is 128 bytes

    mapping(uint256 => uint256) public chainIdOfIndex;
    mapping(uint256 => uint256) public indexOfChainId;
    mapping(uint256 => uint256[4]) public historyOfTokenId;
    mapping(uint256 => uint256) public numTransferForTokenId;

    function _setChainIdIndexLookup(uint256[] memory chainIdsToSet, uint256 startIndex) internal {
        if (startIndex + chainIdsToSet.length > 256) {
          revert YouAreHistory__ChainIndexTooLarge();
        }

        for (uint i; i < chainIdsToSet.length; ++i) {
          chainIdOfIndex[startIndex + i] = chainIdsToSet[i];
          indexOfChainId[chainIdsToSet[i]] = startIndex + i;
        }
    }

    function _initHistory (uint256 _tokenId) internal {
        historyOfTokenId[_tokenId][0] = indexOfChainId[block.chainid];
        numTransferForTokenId[_tokenId] = 1;
    }

    function _updateChainHistory (uint256 _tokenId, uint256[4] memory _history, uint _numTransfersSoFar) internal {
        uint256 transferIndex = _numTransfersSoFar % MAX_CHAIN_HISTORY_LENGTH;

        // Which array in the uint256[4] to index into
        uint256 historyArrayIndex = transferIndex / 32;

        // Which 8 bits to overwrite
        uint256 historyArraySubIndex = (transferIndex % 32) * 8;

        // Create bitmask to clear the 8 bits associated with the new chain index
        uint256 bitmask = ~(uint256(0xFF) << historyArraySubIndex);

        // Clear the bits
        uint256 clearedHistory = _history[historyArrayIndex] & bitmask;

        // Set the new bits
        _history[historyArrayIndex] = clearedHistory | (indexOfChainId[block.chainid] << historyArraySubIndex);

        // Store
        for (uint i = 0; i < 4; i++) {
            historyOfTokenId[_tokenId][i] = _history[i];
        }

        // store the number of transfers + 1
        numTransferForTokenId[_tokenId] = _numTransfersSoFar + 1;
    }

    function _getHistories(uint[] memory tokenIds) internal view returns (uint256[4][] memory) {
        uint256[4][] memory histories = new uint256[4][](tokenIds.length);
        for (uint i; i < tokenIds.length; i++) {
            histories[i] = historyOfTokenId[tokenIds[i]];
        }
        return histories;
    }

    function _getTransferNumbers(uint[] memory tokenIds) internal view returns (uint256[] memory) {
        uint256[] memory numTransfers = new uint256[](tokenIds.length);
        for (uint i; i < tokenIds.length; i++) {
            numTransfers[i] = numTransferForTokenId[tokenIds[i]];
        }
        return numTransfers;
    }

    function _getHistoryUnpacked(uint256 tokenId) internal view returns (uint256[] memory) {
        uint256 numTransfers = numTransferForTokenId[tokenId];
        uint256 resultLength = numTransfers > MAX_CHAIN_HISTORY_LENGTH ? MAX_CHAIN_HISTORY_LENGTH : numTransfers;
        uint256[] memory result = new uint256[](resultLength);
        uint256[4] memory history = historyOfTokenId[tokenId];
        for (uint i = 0; i < result.length; i++) {
            uint256 transferIndex = (numTransfers - 1 - i) % MAX_CHAIN_HISTORY_LENGTH; // Needs to be a rolling index
            uint256 historyArrayIndex = transferIndex / 32;
            uint256 historyArraySubIndex = (transferIndex % 32) * 8;
            uint256 chainIndex = (history[historyArrayIndex] >> historyArraySubIndex) & 0xFF;
            result[i] = chainIdOfIndex[chainIndex];
        }
        return result;
    }

    function getHistory(uint tokenId) external view returns (uint256[] memory) {
        return _getHistoryUnpacked(tokenId);
    }

    function getHistories(uint[] memory tokenIds) external view returns (uint256[][] memory) {
        uint256 [][] memory result = new uint256[][](tokenIds.length);
        for (uint i; i < tokenIds.length; i++) {
            result[i] = _getHistoryUnpacked(tokenIds[i]);
        }
        return result;
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./interfaces/IONFT721Core.sol";
import "./YouAreHistory.sol";
import "../lzApp/NonblockingLzApp.sol";
import "@openzeppelin/contracts/utils/introspection/ERC165.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";

abstract contract YouAreONFT721Core is YouAreHistory, NonblockingLzApp, ERC165, ReentrancyGuard, IONFT721Core {
    uint16 public constant FUNCTION_TYPE_SEND = 1;

    struct StoredCredit {
        uint16 srcChainId;
        address toAddress;
        uint index; // which index of the tokenIds remain
        bool creditsRemain;
    }

    uint public minGasToTransferAndStore = 150_000; // Set Default
    mapping(uint16 => uint) public dstChainIdToBatchLimit;
    mapping(uint16 => uint) public dstChainIdToTransferGas; // per transfer amount of gas required to mint/transfer on the dst
    mapping(bytes32 => StoredCredit) public storedCredits;

    constructor() NonblockingLzApp() {}

    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
        return interfaceId == type(IONFT721Core).interfaceId || super.supportsInterface(interfaceId);
    }

    function estimateSendFee(
        uint16 _dstChainId,
        bytes memory _toAddress,
        uint _tokenId,
        bool _useZro,
        bytes memory _adapterParams
    ) public view virtual override returns (uint nativeFee, uint zroFee) {
        bytes memory payload = abi.encode(_toAddress, _toSingletonArray(_tokenId), _getHistories(_toSingletonArray(_tokenId)), _getTransferNumbers(_toSingletonArray(_tokenId)));
        return lzEndpoint.estimateFees(_dstChainId, address(this), payload, _useZro, _adapterParams);
    }

    function estimateSendBatchFee(
        uint16 _dstChainId,
        bytes memory _toAddress,
        uint[] memory _tokenIds,
        bool _useZro,
        bytes memory _adapterParams
    ) public view virtual override returns (uint nativeFee, uint zroFee) {
        bytes memory payload = abi.encode(_toAddress, _tokenIds, _getHistories(_tokenIds), _getTransferNumbers(_tokenIds));
        return lzEndpoint.estimateFees(_dstChainId, address(this), payload, _useZro, _adapterParams);
    }

    function sendFrom(
        address _from,
        uint16 _dstChainId,
        bytes memory _toAddress,
        uint _tokenId,
        address payable _refundAddress,
        address _zroPaymentAddress,
        bytes memory _adapterParams
    ) public payable virtual override {
        _send(
            _from,
            _dstChainId,
            _toAddress,
            _toSingletonArray(_tokenId),
            _getHistories(_toSingletonArray(_tokenId)),
            _getTransferNumbers(_toSingletonArray(_tokenId)),
            _refundAddress,
            _zroPaymentAddress,
            _adapterParams
        );
    }

    function sendBatchFrom(
        address _from,
        uint16 _dstChainId,
        bytes memory _toAddress,
        uint[] memory _tokenIds,
        address payable _refundAddress,
        address _zroPaymentAddress,
        bytes memory _adapterParams
    ) public payable virtual override {
        _send(_from, _dstChainId, _toAddress, _tokenIds, _getHistories(_tokenIds), _getTransferNumbers(_tokenIds), _refundAddress, _zroPaymentAddress, _adapterParams);
    }

    function _send(
        address _from,
        uint16 _dstChainId,
        bytes memory _toAddress,
        uint[] memory _tokenIds,
        uint256[4][] memory _histories,
        uint256[] memory _transfers,
        address payable _refundAddress,
        address _zroPaymentAddress,
        bytes memory _adapterParams
    ) internal virtual {
        // allow 1 by default
        require(_tokenIds.length > 0, "tokenIds[] is empty");
        require(_tokenIds.length == 1 || _tokenIds.length <= dstChainIdToBatchLimit[_dstChainId], "batch size exceeds dst batch limit");

        for (uint i = 0; i < _tokenIds.length; i++) {
            _debitFrom(_from, _dstChainId, _toAddress, _tokenIds[i]);
        }

        bytes memory payload = abi.encode(_toAddress, _tokenIds, _histories, _transfers);

        _checkGasLimit(_dstChainId, FUNCTION_TYPE_SEND, _adapterParams, dstChainIdToTransferGas[_dstChainId] * _tokenIds.length);
        _lzSend(_dstChainId, payload, _refundAddress, _zroPaymentAddress, _adapterParams, msg.value);
        emit SendToChain(_dstChainId, _from, _toAddress, _tokenIds);
    }

    function _nonblockingLzReceive(
        uint16 _srcChainId,
        bytes memory _srcAddress,
        uint64 /*_nonce*/,
        bytes memory _payload
    ) internal virtual override {
        // decode and load the toAddress
        (bytes memory toAddressBytes, uint[] memory tokenIds, uint256[4][] memory histories, uint256[] memory transfers) = abi.decode(_payload, (bytes, uint[], uint256[4][], uint256[]));

        address toAddress;
        assembly {
            toAddress := mload(add(toAddressBytes, 20))
        }

        uint nextIndex = _creditTill(_srcChainId, toAddress, 0, tokenIds, histories, transfers);
        if (nextIndex < tokenIds.length) {
            // not enough gas to complete transfers, store to be cleared in another tx
            bytes32 hashedPayload = keccak256(_payload);
            storedCredits[hashedPayload] = StoredCredit(_srcChainId, toAddress, nextIndex, true);
            emit CreditStored(hashedPayload, _payload);
        }

        emit ReceiveFromChain(_srcChainId, _srcAddress, toAddress, tokenIds);
    }

    // Public function for anyone to clear and deliver the remaining batch sent tokenIds
    function clearCredits(bytes memory _payload) external virtual nonReentrant {
        bytes32 hashedPayload = keccak256(_payload);
        require(storedCredits[hashedPayload].creditsRemain, "no credits stored");

        (, uint[] memory tokenIds, uint256[4][] memory histories, uint256[] memory transfers) = abi.decode(_payload, (bytes, uint[], uint256[4][], uint256[]));

        uint nextIndex = _creditTill(
            storedCredits[hashedPayload].srcChainId,
            storedCredits[hashedPayload].toAddress,
            storedCredits[hashedPayload].index,
            tokenIds,
            histories,
            transfers
        );
        require(nextIndex > storedCredits[hashedPayload].index, "not enough gas to process credit transfer");

        if (nextIndex == tokenIds.length) {
            // cleared the credits, delete the element
            delete storedCredits[hashedPayload];
            emit CreditCleared(hashedPayload);
        } else {
            // store the next index to mint
            storedCredits[hashedPayload] = StoredCredit(
                storedCredits[hashedPayload].srcChainId,
                storedCredits[hashedPayload].toAddress,
                nextIndex,
                true
            );
        }
    }

    // When a srcChain has the ability to transfer more chainIds in a single tx than the dst can do.
    // Needs the ability to iterate and stop if the minGasToTransferAndStore is not met
    function _creditTill(
        uint16 _srcChainId,
        address _toAddress,
        uint _startIndex,
        uint[] memory _tokenIds,
        uint256[4][] memory _histories,
        uint[] memory _transfers
    ) internal returns (uint) {
        uint i = _startIndex;
        while (i < _tokenIds.length) {
            // if not enough gas to process, store this index for next loop
            if (gasleft() < minGasToTransferAndStore) break;

            _creditTo(_srcChainId, _toAddress, _tokenIds[i], _histories[i], _transfers[i]);
            i++;
        }

        // indicates the next index to send of tokenIds,
        // if i == tokenIds.length, we are finished
        return i;
    }

    function setMinGasToTransferAndStore(uint _minGasToTransferAndStore) external onlyOwner {
        require(_minGasToTransferAndStore > 0, "minGasToTransferAndStore must be > 0");
        minGasToTransferAndStore = _minGasToTransferAndStore;
        emit SetMinGasToTransferAndStore(_minGasToTransferAndStore);
    }

    // ensures enough gas in adapter params to handle batch transfer gas amounts on the dst
    function setDstChainIdToTransferGas(uint16 _dstChainId, uint _dstChainIdToTransferGas) external onlyOwner {
        require(_dstChainIdToTransferGas > 0, "dstChainIdToTransferGas must be > 0");
        dstChainIdToTransferGas[_dstChainId] = _dstChainIdToTransferGas;
        emit SetDstChainIdToTransferGas(_dstChainId, _dstChainIdToTransferGas);
    }

    // limit on src the amount of tokens to batch send
    function setDstChainIdToBatchLimit(uint16 _dstChainId, uint _dstChainIdToBatchLimit) external onlyOwner {
        require(_dstChainIdToBatchLimit > 0, "dstChainIdToBatchLimit must be > 0");
        dstChainIdToBatchLimit[_dstChainId] = _dstChainIdToBatchLimit;
        emit SetDstChainIdToBatchLimit(_dstChainId, _dstChainIdToBatchLimit);
    }

    function _debitFrom(address _from, uint16 _dstChainId, bytes memory _toAddress, uint _tokenId) internal virtual;

    function _creditTo(uint16 _srcChainId, address _toAddress, uint _tokenId, uint256[4] memory _history, uint256 _transfers) internal virtual;

    function _toSingletonArray(uint element) internal pure returns (uint[] memory) {
        uint[] memory array = new uint[](1);
        array[0] = element;
        return array;
    }

    function _toSingletonArray(uint256[] memory element) internal pure returns (uint256[][] memory) {
        uint256[][] memory array = new uint256[][](1);
        array[0] = element;
        return array;
    }

    function _toSingletonArray(uint256[4] memory element) internal pure returns (uint256[4][] memory) {
        uint256[4][] memory array = new uint256[4][](1);
        array[0] = element;
        return array;
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./interfaces/IONFT721.sol";
import "./YouAreONFT721Core.sol";
import "solady/src/tokens/ERC721.sol";

abstract contract YouAreONFT721Mod is YouAreONFT721Core, ERC721, IONFT721 {
    constructor() ERC721() YouAreONFT721Core() {}

    function supportsInterface(bytes4 interfaceId) public view virtual override(YouAreONFT721Core, ERC721, IERC165) returns (bool) {
        return interfaceId == type(IONFT721).interfaceId || super.supportsInterface(interfaceId);
    }

    function rawOwnerOf(uint tokenId) public view returns (address) {
        if (_exists(tokenId)) {
            return ownerOf(tokenId);
        }
        return address(0);
    }

    function rawOwnersOf(uint[] memory tokenIds) public view returns (address[] memory) {
        address[] memory owners = new address[](tokenIds.length);
        for (uint i = 0; i < tokenIds.length; i++) {
            owners[i] = rawOwnerOf(tokenIds[i]);
        }
        return owners;
    }
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;

/// @notice Simple single owner authorization mixin.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/auth/Ownable.sol)
///
/// @dev Note:
/// This implementation does NOT auto-initialize the owner to `msg.sender`.
/// You MUST call the `_initializeOwner` in the constructor / initializer.
///
/// While the ownable portion follows
/// [EIP-173](https://eips.ethereum.org/EIPS/eip-173) for compatibility,
/// the nomenclature for the 2-step ownership handover may be unique to this codebase.
abstract contract Ownable {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                       CUSTOM ERRORS                        */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The caller is not authorized to call the function.
    error Unauthorized();

    /// @dev The `newOwner` cannot be the zero address.
    error NewOwnerIsZeroAddress();

    /// @dev The `pendingOwner` does not have a valid handover request.
    error NoHandoverRequest();

    /// @dev Cannot double-initialize.
    error AlreadyInitialized();

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                           EVENTS                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The ownership is transferred from `oldOwner` to `newOwner`.
    /// This event is intentionally kept the same as OpenZeppelin's Ownable to be
    /// compatible with indexers and [EIP-173](https://eips.ethereum.org/EIPS/eip-173),
    /// despite it not being as lightweight as a single argument event.
    event OwnershipTransferred(address indexed oldOwner, address indexed newOwner);

    /// @dev An ownership handover to `pendingOwner` has been requested.
    event OwnershipHandoverRequested(address indexed pendingOwner);

    /// @dev The ownership handover to `pendingOwner` has been canceled.
    event OwnershipHandoverCanceled(address indexed pendingOwner);

    /// @dev `keccak256(bytes("OwnershipTransferred(address,address)"))`.
    uint256 private constant _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE =
        0x8be0079c531659141344cd1fd0a4f28419497f9722a3daafe3b4186f6b6457e0;

    /// @dev `keccak256(bytes("OwnershipHandoverRequested(address)"))`.
    uint256 private constant _OWNERSHIP_HANDOVER_REQUESTED_EVENT_SIGNATURE =
        0xdbf36a107da19e49527a7176a1babf963b4b0ff8cde35ee35d6cd8f1f9ac7e1d;

    /// @dev `keccak256(bytes("OwnershipHandoverCanceled(address)"))`.
    uint256 private constant _OWNERSHIP_HANDOVER_CANCELED_EVENT_SIGNATURE =
        0xfa7b8eab7da67f412cc9575ed43464468f9bfbae89d1675917346ca6d8fe3c92;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                          STORAGE                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The owner slot is given by:
    /// `bytes32(~uint256(uint32(bytes4(keccak256("_OWNER_SLOT_NOT")))))`.
    /// It is intentionally chosen to be a high value
    /// to avoid collision with lower slots.
    /// The choice of manual storage layout is to enable compatibility
    /// with both regular and upgradeable contracts.
    bytes32 internal constant _OWNER_SLOT =
        0xffffffffffffffffffffffffffffffffffffffffffffffffffffffff74873927;

    /// The ownership handover slot of `newOwner` is given by:
    /// ```
    ///     mstore(0x00, or(shl(96, user), _HANDOVER_SLOT_SEED))
    ///     let handoverSlot := keccak256(0x00, 0x20)
    /// ```
    /// It stores the expiry timestamp of the two-step ownership handover.
    uint256 private constant _HANDOVER_SLOT_SEED = 0x389a75e1;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                     INTERNAL FUNCTIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Override to return true to make `_initializeOwner` prevent double-initialization.
    function _guardInitializeOwner() internal pure virtual returns (bool guard) {}

    /// @dev Initializes the owner directly without authorization guard.
    /// This function must be called upon initialization,
    /// regardless of whether the contract is upgradeable or not.
    /// This is to enable generalization to both regular and upgradeable contracts,
    /// and to save gas in case the initial owner is not the caller.
    /// For performance reasons, this function will not check if there
    /// is an existing owner.
    function _initializeOwner(address newOwner) internal virtual {
        if (_guardInitializeOwner()) {
            /// @solidity memory-safe-assembly
            assembly {
                let ownerSlot := _OWNER_SLOT
                if sload(ownerSlot) {
                    mstore(0x00, 0x0dc149f0) // `AlreadyInitialized()`.
                    revert(0x1c, 0x04)
                }
                // Clean the upper 96 bits.
                newOwner := shr(96, shl(96, newOwner))
                // Store the new value.
                sstore(ownerSlot, or(newOwner, shl(255, iszero(newOwner))))
                // Emit the {OwnershipTransferred} event.
                log3(0, 0, _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE, 0, newOwner)
            }
        } else {
            /// @solidity memory-safe-assembly
            assembly {
                // Clean the upper 96 bits.
                newOwner := shr(96, shl(96, newOwner))
                // Store the new value.
                sstore(_OWNER_SLOT, newOwner)
                // Emit the {OwnershipTransferred} event.
                log3(0, 0, _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE, 0, newOwner)
            }
        }
    }

    /// @dev Sets the owner directly without authorization guard.
    function _setOwner(address newOwner) internal virtual {
        if (_guardInitializeOwner()) {
            /// @solidity memory-safe-assembly
            assembly {
                let ownerSlot := _OWNER_SLOT
                // Clean the upper 96 bits.
                newOwner := shr(96, shl(96, newOwner))
                // Emit the {OwnershipTransferred} event.
                log3(0, 0, _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE, sload(ownerSlot), newOwner)
                // Store the new value.
                sstore(ownerSlot, or(newOwner, shl(255, iszero(newOwner))))
            }
        } else {
            /// @solidity memory-safe-assembly
            assembly {
                let ownerSlot := _OWNER_SLOT
                // Clean the upper 96 bits.
                newOwner := shr(96, shl(96, newOwner))
                // Emit the {OwnershipTransferred} event.
                log3(0, 0, _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE, sload(ownerSlot), newOwner)
                // Store the new value.
                sstore(ownerSlot, newOwner)
            }
        }
    }

    /// @dev Throws if the sender is not the owner.
    function _checkOwner() internal view virtual {
        /// @solidity memory-safe-assembly
        assembly {
            // If the caller is not the stored owner, revert.
            if iszero(eq(caller(), sload(_OWNER_SLOT))) {
                mstore(0x00, 0x82b42900) // `Unauthorized()`.
                revert(0x1c, 0x04)
            }
        }
    }

    /// @dev Returns how long a two-step ownership handover is valid for in seconds.
    /// Override to return a different value if needed.
    /// Made internal to conserve bytecode. Wrap it in a public function if needed.
    function _ownershipHandoverValidFor() internal view virtual returns (uint64) {
        return 48 * 3600;
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                  PUBLIC UPDATE FUNCTIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Allows the owner to transfer the ownership to `newOwner`.
    function transferOwnership(address newOwner) public payable virtual onlyOwner {
        /// @solidity memory-safe-assembly
        assembly {
            if iszero(shl(96, newOwner)) {
                mstore(0x00, 0x7448fbae) // `NewOwnerIsZeroAddress()`.
                revert(0x1c, 0x04)
            }
        }
        _setOwner(newOwner);
    }

    /// @dev Allows the owner to renounce their ownership.
    function renounceOwnership() public payable virtual onlyOwner {
        _setOwner(address(0));
    }

    /// @dev Request a two-step ownership handover to the caller.
    /// The request will automatically expire in 48 hours (172800 seconds) by default.
    function requestOwnershipHandover() public payable virtual {
        unchecked {
            uint256 expires = block.timestamp + _ownershipHandoverValidFor();
            /// @solidity memory-safe-assembly
            assembly {
                // Compute and set the handover slot to `expires`.
                mstore(0x0c, _HANDOVER_SLOT_SEED)
                mstore(0x00, caller())
                sstore(keccak256(0x0c, 0x20), expires)
                // Emit the {OwnershipHandoverRequested} event.
                log2(0, 0, _OWNERSHIP_HANDOVER_REQUESTED_EVENT_SIGNATURE, caller())
            }
        }
    }

    /// @dev Cancels the two-step ownership handover to the caller, if any.
    function cancelOwnershipHandover() public payable virtual {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute and set the handover slot to 0.
            mstore(0x0c, _HANDOVER_SLOT_SEED)
            mstore(0x00, caller())
            sstore(keccak256(0x0c, 0x20), 0)
            // Emit the {OwnershipHandoverCanceled} event.
            log2(0, 0, _OWNERSHIP_HANDOVER_CANCELED_EVENT_SIGNATURE, caller())
        }
    }

    /// @dev Allows the owner to complete the two-step ownership handover to `pendingOwner`.
    /// Reverts if there is no existing ownership handover requested by `pendingOwner`.
    function completeOwnershipHandover(address pendingOwner) public payable virtual onlyOwner {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute and set the handover slot to 0.
            mstore(0x0c, _HANDOVER_SLOT_SEED)
            mstore(0x00, pendingOwner)
            let handoverSlot := keccak256(0x0c, 0x20)
            // If the handover does not exist, or has expired.
            if gt(timestamp(), sload(handoverSlot)) {
                mstore(0x00, 0x6f5e8818) // `NoHandoverRequest()`.
                revert(0x1c, 0x04)
            }
            // Set the handover slot to 0.
            sstore(handoverSlot, 0)
        }
        _setOwner(pendingOwner);
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   PUBLIC READ FUNCTIONS                    */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the owner of the contract.
    function owner() public view virtual returns (address result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := sload(_OWNER_SLOT)
        }
    }

    /// @dev Returns the expiry timestamp for the two-step ownership handover to `pendingOwner`.
    function ownershipHandoverExpiresAt(address pendingOwner)
        public
        view
        virtual
        returns (uint256 result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the handover slot.
            mstore(0x0c, _HANDOVER_SLOT_SEED)
            mstore(0x00, pendingOwner)
            // Load the handover slot.
            result := sload(keccak256(0x0c, 0x20))
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                         MODIFIERS                          */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Marks a function as only callable by the owner.
    modifier onlyOwner() virtual {
        _checkOwner();
        _;
    }
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;

/// @notice Simple ERC721 implementation with storage hitchhiking.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/tokens/ERC721.sol)
/// @author Modified from Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC721.sol)
/// @author Modified from OpenZeppelin (https://github.com/OpenZeppelin/openzeppelin-contracts/tree/master/contracts/token/ERC721/ERC721.sol)
///
/// @dev Note:
/// - The ERC721 standard allows for self-approvals.
///   For performance, this implementation WILL NOT revert for such actions.
///   Please add any checks with overrides if desired.
/// - For performance, methods are made payable where permitted by the ERC721 standard.
/// - The `safeTransfer` functions use the identity precompile (0x4)
///   to copy memory internally.
///
/// If you are overriding:
/// - NEVER violate the ERC721 invariant:
///   the balance of an owner MUST always be equal to their number of ownership slots.
///   The transfer functions do not have an underflow guard for user token balances.
/// - Make sure all variables written to storage are properly cleaned
//    (e.g. the bool value for `isApprovedForAll` MUST be either 1 or 0 under the hood).
/// - Check that the overridden function is actually used in the function you want to
///   change the behavior of. Much of the code has been manually inlined for performance.
abstract contract ERC721 {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                         CONSTANTS                          */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev An account can hold up to 4294967295 tokens.
    uint256 internal constant _MAX_ACCOUNT_BALANCE = 0xffffffff;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                       CUSTOM ERRORS                        */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Only the token owner or an approved account can manage the token.
    error NotOwnerNorApproved();

    /// @dev The token does not exist.
    error TokenDoesNotExist();

    /// @dev The token already exists.
    error TokenAlreadyExists();

    /// @dev Cannot query the balance for the zero address.
    error BalanceQueryForZeroAddress();

    /// @dev Cannot mint or transfer to the zero address.
    error TransferToZeroAddress();

    /// @dev The token must be owned by `from`.
    error TransferFromIncorrectOwner();

    /// @dev The recipient's balance has overflowed.
    error AccountBalanceOverflow();

    /// @dev Cannot safely transfer to a contract that does not implement
    /// the ERC721Receiver interface.
    error TransferToNonERC721ReceiverImplementer();

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                           EVENTS                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Emitted when token `id` is transferred from `from` to `to`.
    event Transfer(address indexed from, address indexed to, uint256 indexed id);

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

    /// @dev Emitted when `owner` enables or disables `operator` to manage all of their tokens.
    event ApprovalForAll(address indexed owner, address indexed operator, bool isApproved);

    /// @dev `keccak256(bytes("Transfer(address,address,uint256)"))`.
    uint256 private constant _TRANSFER_EVENT_SIGNATURE =
        0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef;

    /// @dev `keccak256(bytes("Approval(address,address,uint256)"))`.
    uint256 private constant _APPROVAL_EVENT_SIGNATURE =
        0x8c5be1e5ebec7d5bd14f71427d1e84f3dd0314c0f7b2291e5b200ac8c7c3b925;

    /// @dev `keccak256(bytes("ApprovalForAll(address,address,bool)"))`.
    uint256 private constant _APPROVAL_FOR_ALL_EVENT_SIGNATURE =
        0x17307eab39ab6107e8899845ad3d59bd9653f200f220920489ca2b5937696c31;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                          STORAGE                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The ownership data slot of `id` is given by:
    /// ```
    ///     mstore(0x00, id)
    ///     mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
    ///     let ownershipSlot := add(id, add(id, keccak256(0x00, 0x20)))
    /// ```
    /// Bits Layout:
    /// - [0..159]   `addr`
    /// - [160..255] `extraData`
    ///
    /// The approved address slot is given by: `add(1, ownershipSlot)`.
    ///
    /// See: https://notes.ethereum.org/%40vbuterin/verkle_tree_eip
    ///
    /// The balance slot of `owner` is given by:
    /// ```
    ///     mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
    ///     mstore(0x00, owner)
    ///     let balanceSlot := keccak256(0x0c, 0x1c)
    /// ```
    /// Bits Layout:
    /// - [0..31]   `balance`
    /// - [32..255] `aux`
    ///
    /// The `operator` approval slot of `owner` is given by:
    /// ```
    ///     mstore(0x1c, or(_ERC721_MASTER_SLOT_SEED, operator))
    ///     mstore(0x00, owner)
    ///     let operatorApprovalSlot := keccak256(0x0c, 0x30)
    /// ```
    uint256 private constant _ERC721_MASTER_SLOT_SEED = 0x7d8825530a5a2e7a << 192;

    /// @dev Pre-shifted and pre-masked constant.
    uint256 private constant _ERC721_MASTER_SLOT_SEED_MASKED = 0x0a5a2e7a00000000;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                      ERC721 METADATA                       */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the token collection name.
    function name() public view virtual returns (string memory);

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

    /// @dev Returns the Uniform Resource Identifier (URI) for token `id`.
    function tokenURI(uint256 id) public view virtual returns (string memory);

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                           ERC721                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the owner of token `id`.
    ///
    /// Requirements:
    /// - Token `id` must exist.
    function ownerOf(uint256 id) public view virtual returns (address result) {
        result = _ownerOf(id);
        /// @solidity memory-safe-assembly
        assembly {
            if iszero(result) {
                mstore(0x00, 0xceea21b6) // `TokenDoesNotExist()`.
                revert(0x1c, 0x04)
            }
        }
    }

    /// @dev Returns the number of tokens owned by `owner`.
    ///
    /// Requirements:
    /// - `owner` must not be the zero address.
    function balanceOf(address owner) public view virtual returns (uint256 result) {
        /// @solidity memory-safe-assembly
        assembly {
            // Revert if the `owner` is the zero address.
            if iszero(owner) {
                mstore(0x00, 0x8f4eb604) // `BalanceQueryForZeroAddress()`.
                revert(0x1c, 0x04)
            }
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            mstore(0x00, owner)
            result := and(sload(keccak256(0x0c, 0x1c)), _MAX_ACCOUNT_BALANCE)
        }
    }

    /// @dev Returns the account approved to manage token `id`.
    ///
    /// Requirements:
    /// - Token `id` must exist.
    function getApproved(uint256 id) public view virtual returns (address result) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, id)
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            let ownershipSlot := add(id, add(id, keccak256(0x00, 0x20)))
            if iszero(shl(96, sload(ownershipSlot))) {
                mstore(0x00, 0xceea21b6) // `TokenDoesNotExist()`.
                revert(0x1c, 0x04)
            }
            result := sload(add(1, ownershipSlot))
        }
    }

    /// @dev Sets `account` as the approved account to manage token `id`.
    ///
    /// Requirements:
    /// - Token `id` must exist.
    /// - The caller must be the owner of the token,
    ///   or an approved operator for the token owner.
    ///
    /// Emits an {Approval} event.
    function approve(address account, uint256 id) public payable virtual {
        _approve(msg.sender, account, id);
    }

    /// @dev Returns whether `operator` is approved to manage the tokens of `owner`.
    function isApprovedForAll(address owner, address operator)
        public
        view
        virtual
        returns (bool result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x1c, operator)
            mstore(0x08, _ERC721_MASTER_SLOT_SEED_MASKED)
            mstore(0x00, owner)
            result := sload(keccak256(0x0c, 0x30))
        }
    }

    /// @dev Sets whether `operator` is approved to manage the tokens of the caller.
    ///
    /// Emits an {ApprovalForAll} event.
    function setApprovalForAll(address operator, bool isApproved) public virtual {
        /// @solidity memory-safe-assembly
        assembly {
            // Convert to 0 or 1.
            isApproved := iszero(iszero(isApproved))
            // Update the `isApproved` for (`msg.sender`, `operator`).
            mstore(0x1c, operator)
            mstore(0x08, _ERC721_MASTER_SLOT_SEED_MASKED)
            mstore(0x00, caller())
            sstore(keccak256(0x0c, 0x30), isApproved)
            // Emit the {ApprovalForAll} event.
            mstore(0x00, isApproved)
            // forgefmt: disable-next-item
            log3(0x00, 0x20, _APPROVAL_FOR_ALL_EVENT_SIGNATURE, caller(), shr(96, shl(96, operator)))
        }
    }

    /// @dev Transfers token `id` from `from` to `to`.
    ///
    /// Requirements:
    ///
    /// - Token `id` must exist.
    /// - `from` must be the owner of the token.
    /// - `to` cannot be the zero address.
    /// - The caller must be the owner of the token, or be approved to manage the token.
    ///
    /// Emits a {Transfer} event.
    function transferFrom(address from, address to, uint256 id) public payable virtual {
        _beforeTokenTransfer(from, to, id);
        /// @solidity memory-safe-assembly
        assembly {
            // Clear the upper 96 bits.
            let bitmaskAddress := shr(96, not(0))
            from := and(bitmaskAddress, from)
            to := and(bitmaskAddress, to)
            // Load the ownership data.
            mstore(0x00, id)
            mstore(0x1c, or(_ERC721_MASTER_SLOT_SEED, caller()))
            let ownershipSlot := add(id, add(id, keccak256(0x00, 0x20)))
            let ownershipPacked := sload(ownershipSlot)
            let owner := and(bitmaskAddress, ownershipPacked)
            // Revert if `from` is not the owner, or does not exist.
            if iszero(mul(owner, eq(owner, from))) {
                if iszero(owner) {
                    mstore(0x00, 0xceea21b6) // `TokenDoesNotExist()`.
                    revert(0x1c, 0x04)
                }
                mstore(0x00, 0xa1148100) // `TransferFromIncorrectOwner()`.
                revert(0x1c, 0x04)
            }
            // Revert if `to` is the zero address.
            if iszero(to) {
                mstore(0x00, 0xea553b34) // `TransferToZeroAddress()`.
                revert(0x1c, 0x04)
            }
            // Load, check, and update the token approval.
            {
                mstore(0x00, from)
                let approvedAddress := sload(add(1, ownershipSlot))
                // Revert if the caller is not the owner, nor approved.
                if iszero(or(eq(caller(), from), eq(caller(), approvedAddress))) {
                    if iszero(sload(keccak256(0x0c, 0x30))) {
                        mstore(0x00, 0x4b6e7f18) // `NotOwnerNorApproved()`.
                        revert(0x1c, 0x04)
                    }
                }
                // Delete the approved address if any.
                if approvedAddress { sstore(add(1, ownershipSlot), 0) }
            }
            // Update with the new owner.
            sstore(ownershipSlot, xor(ownershipPacked, xor(from, to)))
            // Decrement the balance of `from`.
            {
                let fromBalanceSlot := keccak256(0x0c, 0x1c)
                sstore(fromBalanceSlot, sub(sload(fromBalanceSlot), 1))
            }
            // Increment the balance of `to`.
            {
                mstore(0x00, to)
                let toBalanceSlot := keccak256(0x0c, 0x1c)
                let toBalanceSlotPacked := add(sload(toBalanceSlot), 1)
                if iszero(and(toBalanceSlotPacked, _MAX_ACCOUNT_BALANCE)) {
                    mstore(0x00, 0x01336cea) // `AccountBalanceOverflow()`.
                    revert(0x1c, 0x04)
                }
                sstore(toBalanceSlot, toBalanceSlotPacked)
            }
            // Emit the {Transfer} event.
            log4(codesize(), 0x00, _TRANSFER_EVENT_SIGNATURE, from, to, id)
        }
        _afterTokenTransfer(from, to, id);
    }

    /// @dev Equivalent to `safeTransferFrom(from, to, id, "")`.
    function safeTransferFrom(address from, address to, uint256 id) public payable virtual {
        transferFrom(from, to, id);
        if (_hasCode(to)) _checkOnERC721Received(from, to, id, "");
    }

    /// @dev Transfers token `id` from `from` to `to`.
    ///
    /// Requirements:
    ///
    /// - Token `id` must exist.
    /// - `from` must be the owner of the token.
    /// - `to` cannot be the zero address.
    /// - The caller must be the owner of the token, or be approved to manage the token.
    /// - If `to` refers to a smart contract, it must implement
    ///   {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
    ///
    /// Emits a {Transfer} event.
    function safeTransferFrom(address from, address to, uint256 id, bytes calldata data)
        public
        payable
        virtual
    {
        transferFrom(from, to, id);
        if (_hasCode(to)) _checkOnERC721Received(from, to, id, data);
    }

    /// @dev Returns true if this contract implements the interface defined by `interfaceId`.
    /// See: https://eips.ethereum.org/EIPS/eip-165
    /// This function call must use less than 30000 gas.
    function supportsInterface(bytes4 interfaceId) public view virtual returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            let s := shr(224, interfaceId)
            // ERC165: 0x01ffc9a7, ERC721: 0x80ac58cd, ERC721Metadata: 0x5b5e139f.
            result := or(or(eq(s, 0x01ffc9a7), eq(s, 0x80ac58cd)), eq(s, 0x5b5e139f))
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                  INTERNAL QUERY FUNCTIONS                  */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns if token `id` exists.
    function _exists(uint256 id) internal view virtual returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, id)
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            result := iszero(iszero(shl(96, sload(add(id, add(id, keccak256(0x00, 0x20)))))))
        }
    }

    /// @dev Returns the owner of token `id`.
    /// Returns the zero address instead of reverting if the token does not exist.
    function _ownerOf(uint256 id) internal view virtual returns (address result) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, id)
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            result := shr(96, shl(96, sload(add(id, add(id, keccak256(0x00, 0x20))))))
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*            INTERNAL DATA HITCHHIKING FUNCTIONS             */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    // For performance, no events are emitted for the hitchhiking setters.
    // Please emit your own events if required.

    /// @dev Returns the auxiliary data for `owner`.
    /// Minting, transferring, burning the tokens of `owner` will not change the auxiliary data.
    /// Auxiliary data can be set for any address, even if it does not have any tokens.
    function _getAux(address owner) internal view virtual returns (uint224 result) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            mstore(0x00, owner)
            result := shr(32, sload(keccak256(0x0c, 0x1c)))
        }
    }

    /// @dev Set the auxiliary data for `owner` to `value`.
    /// Minting, transferring, burning the tokens of `owner` will not change the auxiliary data.
    /// Auxiliary data can be set for any address, even if it does not have any tokens.
    function _setAux(address owner, uint224 value) internal virtual {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            mstore(0x00, owner)
            let balanceSlot := keccak256(0x0c, 0x1c)
            let packed := sload(balanceSlot)
            sstore(balanceSlot, xor(packed, shl(32, xor(value, shr(32, packed)))))
        }
    }

    /// @dev Returns the extra data for token `id`.
    /// Minting, transferring, burning a token will not change the extra data.
    /// The extra data can be set on a non-existent token.
    function _getExtraData(uint256 id) internal view virtual returns (uint96 result) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, id)
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            result := shr(160, sload(add(id, add(id, keccak256(0x00, 0x20)))))
        }
    }

    /// @dev Sets the extra data for token `id` to `value`.
    /// Minting, transferring, burning a token will not change the extra data.
    /// The extra data can be set on a non-existent token.
    function _setExtraData(uint256 id, uint96 value) internal virtual {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, id)
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            let ownershipSlot := add(id, add(id, keccak256(0x00, 0x20)))
            let packed := sload(ownershipSlot)
            sstore(ownershipSlot, xor(packed, shl(160, xor(value, shr(160, packed)))))
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                  INTERNAL MINT FUNCTIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Mints token `id` to `to`.
    ///
    /// Requirements:
    ///
    /// - Token `id` must not exist.
    /// - `to` cannot be the zero address.
    ///
    /// Emits a {Transfer} event.
    function _mint(address to, uint256 id) internal virtual {
        _beforeTokenTransfer(address(0), to, id);
        /// @solidity memory-safe-assembly
        assembly {
            // Clear the upper 96 bits.
            to := shr(96, shl(96, to))
            // Revert if `to` is the zero address.
            if iszero(to) {
                mstore(0x00, 0xea553b34) // `TransferToZeroAddress()`.
                revert(0x1c, 0x04)
            }
            // Load the ownership data.
            mstore(0x00, id)
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            let ownershipSlot := add(id, add(id, keccak256(0x00, 0x20)))
            let ownershipPacked := sload(ownershipSlot)
            // Revert if the token already exists.
            if shl(96, ownershipPacked) {
                mstore(0x00, 0xc991cbb1) // `TokenAlreadyExists()`.
                revert(0x1c, 0x04)
            }
            // Update with the owner.
            sstore(ownershipSlot, or(ownershipPacked, to))
            // Increment the balance of the owner.
            {
                mstore(0x00, to)
                let balanceSlot := keccak256(0x0c, 0x1c)
                let balanceSlotPacked := add(sload(balanceSlot), 1)
                if iszero(and(balanceSlotPacked, _MAX_ACCOUNT_BALANCE)) {
                    mstore(0x00, 0x01336cea) // `AccountBalanceOverflow()`.
                    revert(0x1c, 0x04)
                }
                sstore(balanceSlot, balanceSlotPacked)
            }
            // Emit the {Transfer} event.
            log4(codesize(), 0x00, _TRANSFER_EVENT_SIGNATURE, 0, to, id)
        }
        _afterTokenTransfer(address(0), to, id);
    }

    /// @dev Equivalent to `_safeMint(to, id, "")`.
    function _safeMint(address to, uint256 id) internal virtual {
        _safeMint(to, id, "");
    }

    /// @dev Mints token `id` to `to`.
    ///
    /// Requirements:
    ///
    /// - Token `id` must not exist.
    /// - `to` cannot be the zero address.
    /// - If `to` refers to a smart contract, it must implement
    ///   {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
    ///
    /// Emits a {Transfer} event.
    function _safeMint(address to, uint256 id, bytes memory data) internal virtual {
        _mint(to, id);
        if (_hasCode(to)) _checkOnERC721Received(address(0), to, id, data);
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                  INTERNAL BURN FUNCTIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Equivalent to `_burn(address(0), id)`.
    function _burn(uint256 id) internal virtual {
        _burn(address(0), id);
    }

    /// @dev Destroys token `id`, using `by`.
    ///
    /// Requirements:
    ///
    /// - Token `id` must exist.
    /// - If `by` is not the zero address,
    ///   it must be the owner of the token, or be approved to manage the token.
    ///
    /// Emits a {Transfer} event.
    function _burn(address by, uint256 id) internal virtual {
        address owner = ownerOf(id);
        _beforeTokenTransfer(owner, address(0), id);
        /// @solidity memory-safe-assembly
        assembly {
            // Clear the upper 96 bits.
            by := shr(96, shl(96, by))
            // Load the ownership data.
            mstore(0x00, id)
            mstore(0x1c, or(_ERC721_MASTER_SLOT_SEED, by))
            let ownershipSlot := add(id, add(id, keccak256(0x00, 0x20)))
            let ownershipPacked := sload(ownershipSlot)
            // Reload the owner in case it is changed in `_beforeTokenTransfer`.
            owner := shr(96, shl(96, ownershipPacked))
            // Revert if the token does not exist.
            if iszero(owner) {
                mstore(0x00, 0xceea21b6) // `TokenDoesNotExist()`.
                revert(0x1c, 0x04)
            }
            // Load and check the token approval.
            {
                mstore(0x00, owner)
                let approvedAddress := sload(add(1, ownershipSlot))
                // If `by` is not the zero address, do the authorization check.
                // Revert if the `by` is not the owner, nor approved.
                if iszero(or(iszero(by), or(eq(by, owner), eq(by, approvedAddress)))) {
                    if iszero(sload(keccak256(0x0c, 0x30))) {
                        mstore(0x00, 0x4b6e7f18) // `NotOwnerNorApproved()`.
                        revert(0x1c, 0x04)
                    }
                }
                // Delete the approved address if any.
                if approvedAddress { sstore(add(1, ownershipSlot), 0) }
            }
            // Clear the owner.
            sstore(ownershipSlot, xor(ownershipPacked, owner))
            // Decrement the balance of `owner`.
            {
                let balanceSlot := keccak256(0x0c, 0x1c)
                sstore(balanceSlot, sub(sload(balanceSlot), 1))
            }
            // Emit the {Transfer} event.
            log4(codesize(), 0x00, _TRANSFER_EVENT_SIGNATURE, owner, 0, id)
        }
        _afterTokenTransfer(owner, address(0), id);
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                INTERNAL APPROVAL FUNCTIONS                 */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns whether `account` is the owner of token `id`, or is approved to manage it.
    ///
    /// Requirements:
    /// - Token `id` must exist.
    function _isApprovedOrOwner(address account, uint256 id)
        internal
        view
        virtual
        returns (bool result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            result := 1
            // Clear the upper 96 bits.
            account := shr(96, shl(96, account))
            // Load the ownership data.
            mstore(0x00, id)
            mstore(0x1c, or(_ERC721_MASTER_SLOT_SEED, account))
            let ownershipSlot := add(id, add(id, keccak256(0x00, 0x20)))
            let owner := shr(96, shl(96, sload(ownershipSlot)))
            // Revert if the token does not exist.
            if iszero(owner) {
                mstore(0x00, 0xceea21b6) // `TokenDoesNotExist()`.
                revert(0x1c, 0x04)
            }
            // Check if `account` is the `owner`.
            if iszero(eq(account, owner)) {
                mstore(0x00, owner)
                // Check if `account` is approved to manage the token.
                if iszero(sload(keccak256(0x0c, 0x30))) {
                    result := eq(account, sload(add(1, ownershipSlot)))
                }
            }
        }
    }

    /// @dev Returns the account approved to manage token `id`.
    /// Returns the zero address instead of reverting if the token does not exist.
    function _getApproved(uint256 id) internal view virtual returns (address result) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, id)
            mstore(0x1c, _ERC721_MASTER_SLOT_SEED)
            result := sload(add(1, add(id, add(id, keccak256(0x00, 0x20)))))
        }
    }

    /// @dev Equivalent to `_approve(address(0), account, id)`.
    function _approve(address account, uint256 id) internal virtual {
        _approve(address(0), account, id);
    }

    /// @dev Sets `account` as the approved account to manage token `id`, using `by`.
    ///
    /// Requirements:
    /// - Token `id` must exist.
    /// - If `by` is not the zero address, `by` must be the owner
    ///   or an approved operator for the token owner.
    ///
    /// Emits a {Transfer} event.
    function _approve(address by, address account, uint256 id) internal virtual {
        assembly {
            // Clear the upper 96 bits.
            let bitmaskAddress := shr(96, not(0))
            account := and(bitmaskAddress, account)
            by := and(bitmaskAddress, by)
            // Load the owner of the token.
            mstore(0x00, id)
            mstore(0x1c, or(_ERC721_MASTER_SLOT_SEED, by))
            let ownershipSlot := add(id, add(id, keccak256(0x00, 0x20)))
            let owner := and(bitmaskAddress, sload(ownershipSlot))
            // Revert if the token does not exist.
            if iszero(owner) {
                mstore(0x00, 0xceea21b6) // `TokenDoesNotExist()`.
                revert(0x1c, 0x04)
            }
            // If `by` is not the zero address, do the authorization check.
            // Revert if `by` is not the owner, nor approved.
            if iszero(or(iszero(by), eq(by, owner))) {
                mstore(0x00, owner)
                if iszero(sload(keccak256(0x0c, 0x30))) {
                    mstore(0x00, 0x4b6e7f18) // `NotOwnerNorApproved()`.
                    revert(0x1c, 0x04)
                }
            }
            // Sets `account` as the approved account to manage `id`.
            sstore(add(1, ownershipSlot), account)
            // Emit the {Approval} event.
            log4(codesize(), 0x00, _APPROVAL_EVENT_SIGNATURE, owner, account, id)
        }
    }

    /// @dev Approve or remove the `operator` as an operator for `by`,
    /// without authorization checks.
    ///
    /// Emits an {ApprovalForAll} event.
    function _setApprovalForAll(address by, address operator, bool isApproved) internal virtual {
        /// @solidity memory-safe-assembly
        assembly {
            // Clear the upper 96 bits.
            by := shr(96, shl(96, by))
            operator := shr(96, shl(96, operator))
            // Convert to 0 or 1.
            isApproved := iszero(iszero(isApproved))
            // Update the `isApproved` for (`by`, `operator`).
            mstore(0x1c, or(_ERC721_MASTER_SLOT_SEED, operator))
            mstore(0x00, by)
            sstore(keccak256(0x0c, 0x30), isApproved)
            // Emit the {ApprovalForAll} event.
            mstore(0x00, isApproved)
            log3(0x00, 0x20, _APPROVAL_FOR_ALL_EVENT_SIGNATURE, by, operator)
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                INTERNAL TRANSFER FUNCTIONS                 */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Equivalent to `_transfer(address(0), from, to, id)`.
    function _transfer(address from, address to, uint256 id) internal virtual {
        _transfer(address(0), from, to, id);
    }

    /// @dev Transfers token `id` from `from` to `to`.
    ///
    /// Requirements:
    ///
    /// - Token `id` must exist.
    /// - `from` must be the owner of the token.
    /// - `to` cannot be the zero address.
    /// - If `by` is not the zero address,
    ///   it must be the owner of the token, or be approved to manage the token.
    ///
    /// Emits a {Transfer} event.
    function _transfer(address by, address from, address to, uint256 id) internal virtual {
        _beforeTokenTransfer(from, to, id);
        /// @solidity memory-safe-assembly
        assembly {
            // Clear the upper 96 bits.
            let bitmaskAddress := shr(96, not(0))
            from := and(bitmaskAddress, from)
            to := and(bitmaskAddress, to)
            by := and(bitmaskAddress, by)
            // Load the ownership data.
            mstore(0x00, id)
            mstore(0x1c, or(_ERC721_MASTER_SLOT_SEED, by))
            let ownershipSlot := add(id, add(id, keccak256(0x00, 0x20)))
            let ownershipPacked := sload(ownershipSlot)
            let owner := and(bitmaskAddress, ownershipPacked)
            // Revert if `from` is not the owner, or does not exist.
            if iszero(mul(owner, eq(owner, from))) {
                if iszero(owner) {
                    mstore(0x00, 0xceea21b6) // `TokenDoesNotExist()`.
                    revert(0x1c, 0x04)
                }
                mstore(0x00, 0xa1148100) // `TransferFromIncorrectOwner()`.
                revert(0x1c, 0x04)
            }
            // Revert if `to` is the zero address.
            if iszero(to) {
                mstore(0x00, 0xea553b34) // `TransferToZeroAddress()`.
                revert(0x1c, 0x04)
            }
            // Load, check, and update the token approval.
            {
                mstore(0x00, from)
                let approvedAddress := sload(add(1, ownershipSlot))
                // If `by` is not the zero address, do the authorization check.
                // Revert if the `by` is not the owner, nor approved.
                if iszero(or(iszero(by), or(eq(by, from), eq(by, approvedAddress)))) {
                    if iszero(sload(keccak256(0x0c, 0x30))) {
                        mstore(0x00, 0x4b6e7f18) // `NotOwnerNorApproved()`.
                        revert(0x1c, 0x04)
                    }
                }
                // Delete the approved address if any.
                if approvedAddress { sstore(add(1, ownershipSlot), 0) }
            }
            // Update with the new owner.
            sstore(ownershipSlot, xor(ownershipPacked, xor(from, to)))
            // Decrement the balance of `from`.
            {
                let fromBalanceSlot := keccak256(0x0c, 0x1c)
                sstore(fromBalanceSlot, sub(sload(fromBalanceSlot), 1))
            }
            // Increment the balance of `to`.
            {
                mstore(0x00, to)
                let toBalanceSlot := keccak256(0x0c, 0x1c)
                let toBalanceSlotPacked := add(sload(toBalanceSlot), 1)
                if iszero(and(toBalanceSlotPacked, _MAX_ACCOUNT_BALANCE)) {
                    mstore(0x00, 0x01336cea) // `AccountBalanceOverflow()`.
                    revert(0x1c, 0x04)
                }
                sstore(toBalanceSlot, toBalanceSlotPacked)
            }
            // Emit the {Transfer} event.
            log4(codesize(), 0x00, _TRANSFER_EVENT_SIGNATURE, from, to, id)
        }
        _afterTokenTransfer(from, to, id);
    }

    /// @dev Equivalent to `_safeTransfer(from, to, id, "")`.
    function _safeTransfer(address from, address to, uint256 id) internal virtual {
        _safeTransfer(from, to, id, "");
    }

    /// @dev Transfers token `id` from `from` to `to`.
    ///
    /// Requirements:
    ///
    /// - Token `id` must exist.
    /// - `from` must be the owner of the token.
    /// - `to` cannot be the zero address.
    /// - The caller must be the owner of the token, or be approved to manage the token.
    /// - If `to` refers to a smart contract, it must implement
    ///   {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
    ///
    /// Emits a {Transfer} event.
    function _safeTransfer(address from, address to, uint256 id, bytes memory data)
        internal
        virtual
    {
        _transfer(address(0), from, to, id);
        if (_hasCode(to)) _checkOnERC721Received(from, to, id, data);
    }

    /// @dev Equivalent to `_safeTransfer(by, from, to, id, "")`.
    function _safeTransfer(address by, address from, address to, uint256 id) internal virtual {
        _safeTransfer(by, from, to, id, "");
    }

    /// @dev Transfers token `id` from `from` to `to`.
    ///
    /// Requirements:
    ///
    /// - Token `id` must exist.
    /// - `from` must be the owner of the token.
    /// - `to` cannot be the zero address.
    /// - If `by` is not the zero address,
    ///   it must be the owner of the token, or be approved to manage the token.
    /// - If `to` refers to a smart contract, it must implement
    ///   {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
    ///
    /// Emits a {Transfer} event.
    function _safeTransfer(address by, address from, address to, uint256 id, bytes memory data)
        internal
        virtual
    {
        _transfer(by, from, to, id);
        if (_hasCode(to)) _checkOnERC721Received(from, to, id, data);
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                    HOOKS FOR OVERRIDING                    */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Hook that is called before any token transfers, including minting and burning.
    function _beforeTokenTransfer(address from, address to, uint256 id) internal virtual {}

    /// @dev Hook that is called after any token transfers, including minting and burning.
    function _afterTokenTransfer(address from, address to, uint256 id) internal virtual {}

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                      PRIVATE HELPERS                       */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns if `a` has bytecode of non-zero length.
    function _hasCode(address a) private view returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := extcodesize(a) // Can handle dirty upper bits.
        }
    }

    /// @dev Perform a call to invoke {IERC721Receiver-onERC721Received} on `to`.
    /// Reverts if the target does not support the function correctly.
    function _checkOnERC721Received(address from, address to, uint256 id, bytes memory data)
        private
    {
        /// @solidity memory-safe-assembly
        assembly {
            // Prepare the calldata.
            let m := mload(0x40)
            let onERC721ReceivedSelector := 0x150b7a02
            mstore(m, onERC721ReceivedSelector)
            mstore(add(m, 0x20), caller()) // The `operator`, which is always `msg.sender`.
            mstore(add(m, 0x40), shr(96, shl(96, from)))
            mstore(add(m, 0x60), id)
            mstore(add(m, 0x80), 0x80)
            let n := mload(data)
            mstore(add(m, 0xa0), n)
            if n { pop(staticcall(gas(), 4, add(data, 0x20), n, add(m, 0xc0), n)) }
            // Revert if the call reverts.
            if iszero(call(gas(), to, 0, add(m, 0x1c), add(n, 0xa4), m, 0x20)) {
                if returndatasize() {
                    // Bubble up the revert if the call reverts.
                    returndatacopy(m, 0x00, returndatasize())
                    revert(m, returndatasize())
                }
            }
            // Load the returndata and compare it.
            if iszero(eq(mload(m), shl(224, onERC721ReceivedSelector))) {
                mstore(0x00, 0xd1a57ed6) // `TransferToNonERC721ReceiverImplementer()`.
                revert(0x1c, 0x04)
            }
        }
    }
}

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