// SPDX-License-Identifier: MIT
pragma solidity ^0.8.24;

import {IERC20} from "@openzeppelin5/contracts/token/ERC20/IERC20.sol";
import {SignatureCheckerLib} from "solady/utils/SignatureCheckerLib.sol";
import {LibBitmap} from "solady/utils/LibBitmap.sol";
import {OwnableRoles} from "solady/auth/OwnableRoles.sol";

import "forge-std/console.sol";

contract ClaimToFame is OwnableRoles {
    using SignatureCheckerLib for address;
    using LibBitmap for LibBitmap.Bitmap;
    IERC20 public fameToken;
    mapping(address => uint256) public signatureNonces;
    mapping(address => LibBitmap.Bitmap) private claimedBitmaps;
    address private signer;

    constructor(address _fameToken, address _signer) {
        fameToken = IERC20(_fameToken);
        signer = _signer;
        _initializeOwner(msg.sender);
    }

    uint256 internal constant SIGNER = _ROLE_0;

    /**
     * @dev Returns the role that controls the signer address.
     */
    function roleSigner() public pure returns (uint256) {
        return SIGNER;
    }

    uint256 internal constant CLAIM_PRIMER = _ROLE_1;

    /**
     * @dev Returns the role that primes which tokens are already claimed when the contract is deployed.
     */
    function roleClaimPrimer() public pure returns (uint256) {
        return CLAIM_PRIMER;
    }

    uint internal constant TREASURER = _ROLE_2;

    /**
     * @dev Returns the role that can withdraw funds from the contract.
     */
    function roleTreasurer() public pure returns (uint256) {
        return TREASURER;
    }

    /**
     * @dev Sets the signer address.
     * @param _signer address Signer address to assign.
     */
    function setSigner(address _signer) external onlyRolesOrOwner(SIGNER) {
        signer = _signer;
    }

    function primeClaim(
        address contractAddress,
        uint16[] calldata tokenIds
    ) external onlyRolesOrOwner(CLAIM_PRIMER) {
        setClaimedTokens(contractAddress, tokenIds);
    }

    function primeClaimWithData(
        address contractAddress,
        bytes calldata packedTokenIds
    ) external onlyRolesOrOwner(CLAIM_PRIMER) {
        setClaimedData(contractAddress, packedTokenIds);
    }

    function withdrawErc20(
        address token,
        uint256 amount
    ) external onlyRolesOrOwner(TREASURER) {
        IERC20(token).transfer(msg.sender, amount);
    }

    function withdrawEth(uint256 amount) external onlyRolesOrOwner(TREASURER) {
        payable(msg.sender).transfer(amount);
    }

    uint256 internal constant MAX_TOKENS = 8888;
    /**
     * @dev Returns packed byte bitmap data that represents all token ids in a packed format.
     * @param tokenIds uint256[] Array of token ids to pack.  Assumed to be sorted in ascending order.
     * @return bytes Packed byte data.
     */
    function generatePackedData(
        uint256[] calldata tokenIds
    ) public pure returns (bytes memory) {
        // First find the maximum token id in the array to determine the size of the bitmap.
        uint256 maxTokenId = tokenIds[tokenIds.length - 1];

        // Create a new bitmap with the maximum token id.
        bytes memory packedData = new bytes((maxTokenId / 8) + 1);

        // Now fill in the bitmap with the token ids by setting each bit to 1 that corresponds to a token id.
        for (uint256 i = 0; i < tokenIds.length; i++) {
            uint256 tokenId = tokenIds[i];
            uint256 byteIndex = tokenId / 8;
            uint256 bitIndex = tokenId % 8;

            packedData[byteIndex] = bytes1(
                uint8(packedData[byteIndex]) | uint8(1 << bitIndex)
            );
        }

        return packedData;
    }

    function generateTokenIds(
        bytes calldata packedData
    ) public pure returns (uint256[] memory) {
        uint256 maxToken = packedData.length * 8;
        uint256[] memory tokenIds = new uint256[](maxToken);
        uint256 count = 0;
        for (uint256 i = 0; i < packedData.length; i++) {
            uint8 byteValue = uint8(packedData[i]);
            for (uint256 j = 0; j < 8; j++) {
                if (byteValue & (1 << j) != 0) {
                    tokenIds[count] = i * 8 + j;
                    count++;
                }
            }
        }
        uint256[] memory result = new uint256[](count);
        for (uint256 i = 0; i < count; i++) {
            result[i] = tokenIds[i];
        }
        return result;
    }

    error AlreadyCalimed(uint256 tokenId);
    /**
     * @dev Sets the claimed tokens for a user by walking through the bits in the packed token ids and setting the corresponding token ids in claimedBitmap.
     * @param packedTokenIds bytes Packed byte data that represents all token ids in a packed format.
     */
    function setClaimedData(
        address contractAddress,
        bytes calldata packedTokenIds
    ) internal {
        LibBitmap.Bitmap storage claimedBitmap = claimedBitmaps[
            contractAddress
        ];
        // Walk through the packedTokenIds to check each bit
        for (uint256 i = 0; i < packedTokenIds.length; i++) {
            uint8 byteValue = uint8(packedTokenIds[i]);
            for (uint256 j = 0; j < 8; j++) {
                if (byteValue & (1 << j) != 0) {
                    uint256 index = i * 8 + j;
                    if (claimedBitmap.get(index)) {
                        revert AlreadyCalimed(index);
                    }
                    claimedBitmap.set(index);
                }
            }
        }
    }

    function setClaimedTokens(
        address contractAddress,
        uint16[] calldata tokenIds
    ) internal {
        LibBitmap.Bitmap storage claimedBitmap = claimedBitmaps[
            contractAddress
        ];
        uint16 length = uint16(tokenIds.length);
        for (uint16 i = 0; i < length; i++) {
            uint16 tokenId = tokenIds[i];
            if (claimedBitmap.get(tokenId)) {
                revert AlreadyCalimed(tokenId);
            }
            claimedBitmap.set(tokenId);
        }
    }

    function hashClaimDataRequest(
        address account,
        address contractAddress,
        uint256 amount,
        uint256 deadline,
        bytes calldata packedTokenIds,
        uint256 nonce
    ) public pure returns (bytes32) {
        return
            keccak256(
                abi.encodePacked(
                    account,
                    contractAddress,
                    amount,
                    deadline,
                    packedTokenIds,
                    nonce
                )
            );
    }

    function hashClaimTokensRequest(
        address account,
        address contractAddress,
        uint256 amount,
        uint256 deadline,
        uint16[] calldata tokenIds,
        uint256 nonce
    ) public pure returns (bytes32) {
        return
            keccak256(
                abi.encodePacked(
                    account,
                    contractAddress,
                    amount,
                    deadline,
                    tokenIds,
                    nonce
                )
            );
    }

    error InvalidSignature();
    error PastDeadline();
    function verifyClaimDataRequest(
        address account,
        address contractAddress,
        uint256 amount,
        uint256 deadline,
        bytes calldata packedTokenIds,
        bytes calldata signature
    ) public {
        if (block.timestamp > deadline) {
            revert PastDeadline();
        }
        bytes32 hash = hashClaimDataRequest(
            account,
            contractAddress,
            amount,
            deadline,
            packedTokenIds,
            signatureNonces[msg.sender]
        );
        if (
            !signer.isValidSignatureNow(
                SignatureCheckerLib.toEthSignedMessageHash(hash),
                signature
            )
        ) {
            revert InvalidSignature();
        }
        signatureNonces[msg.sender]++;
    }

    function verifyClaimTokensRequest(
        address account,
        address contractAddress,
        uint256 amount,
        uint256 deadline,
        uint16[] calldata tokenIds,
        bytes calldata signature
    ) public {
        if (block.timestamp > deadline) {
            revert PastDeadline();
        }
        bytes32 hash = hashClaimTokensRequest(
            account,
            contractAddress,
            amount,
            deadline,
            tokenIds,
            signatureNonces[msg.sender]
        );
        if (
            !signer.isValidSignatureNow(
                SignatureCheckerLib.toEthSignedMessageHash(hash),
                signature
            )
        ) {
            revert InvalidSignature();
        }
        signatureNonces[msg.sender]++;
    }

    function claimWithData(
        address account,
        address contractAddress,
        uint256 amount,
        uint256 deadline,
        bytes calldata packedTokenIds,
        bytes calldata signature
    ) public {
        verifyClaimDataRequest(
            account,
            contractAddress,
            amount,
            deadline,
            packedTokenIds,
            signature
        );
        setClaimedData(contractAddress, packedTokenIds);
        fameToken.transfer(account, amount);
    }

    function claimWithTokens(
        address account,
        address contractAddress,
        uint256 amount,
        uint256 deadline,
        uint16[] calldata tokenIds,
        bytes calldata signature
    ) public {
        verifyClaimTokensRequest(
            account,
            contractAddress,
            amount,
            deadline,
            tokenIds,
            signature
        );
        setClaimedTokens(contractAddress, tokenIds);
        fameToken.transfer(account, amount);
    }

    function isClaimed(
        address contractAddress,
        uint256 tokenId
    ) public view returns (bool) {
        return claimedBitmaps[contractAddress].get(tokenId);
    }

    function isClaimedBatch(
        address contractAddress,
        uint256[] calldata tokenIds
    ) public view returns (bool[] memory) {
        LibBitmap.Bitmap storage claimedBitmap = claimedBitmaps[
            contractAddress
        ];
        uint256 length = tokenIds.length;
        bool[] memory result = new bool[](length);
        for (uint256 i = 0; i < length; i++) {
            result[i] = claimedBitmap.get(tokenIds[i]);
        }
        return result;
    }
}

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

/// @title DN404
/// @notice DN404 is a hybrid ERC20 and ERC721 implementation that mints
/// and burns NFTs based on an account's ERC20 token balance.
///
/// @author vectorized.eth (@optimizoor)
/// @author Quit (@0xQuit)
/// @author Michael Amadi (@AmadiMichaels)
/// @author cygaar (@0xCygaar)
/// @author Thomas (@0xjustadev)
/// @author Harrison (@PopPunkOnChain)
///
/// @dev Note:
/// - The ERC721 data is stored in this base DN404 contract, however a
///   DN404Mirror contract ***MUST*** be deployed and linked during
///   initialization.
/// - For ERC20 transfers, the most recently acquired NFT will be burned / transferred out first.
/// - A unit worth of ERC20 tokens equates to a deed to one NFT token.
///   The skip NFT status determines if this deed is automatically exercised.
///   An account can configure their skip NFT status.
///     * If `getSkipNFT(owner) == true`, ERC20 mints / transfers to `owner`
///       will NOT trigger NFT mints / transfers to `owner` (i.e. deeds are left unexercised).
///     * If `getSkipNFT(owner) == false`, ERC20 mints / transfers to `owner`
///       will trigger NFT mints / transfers to `owner`, until the NFT balance of `owner`
///       is equal to its ERC20 balance divided by the unit (rounded down).
/// - Invariant: `mirror.balanceOf(owner) <= base.balanceOf(owner) / _unit()`.
/// - The gas costs for automatic minting / transferring / burning of NFTs is O(n).
///   This can exceed the block gas limit.
///   Applications and users may need to break up large transfers into a few transactions.
/// - This implementation does not support "safe" transfers for automatic NFT transfers.
/// - The ERC20 token allowances and ERC721 token / operator approvals are separate.
/// - For MEV safety, users should NOT have concurrently open orders for the ERC20 and ERC721.
abstract contract DN404 {
    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                           EVENTS                           */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

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

    /// @dev Emitted when `amount` tokens is approved by `owner` to be used by `spender`.
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 amount
    );

    /// @dev Emitted when `owner` sets their skipNFT flag to `status`.
    event SkipNFTSet(address indexed owner, bool status);

    /// @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("SkipNFTSet(address,bool)"))`.
    uint256 private constant _SKIP_NFT_SET_EVENT_SIGNATURE =
        0xb5a1de456fff688115a4f75380060c23c8532d14ff85f687cc871456d6420393;

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                        CUSTOM ERRORS                       */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Thrown when attempting to double-initialize the contract.
    error DNAlreadyInitialized();

    /// @dev The function can only be called after the contract has been initialized.
    error DNNotInitialized();

    /// @dev Thrown when attempting to transfer or burn more tokens than sender's balance.
    error InsufficientBalance();

    /// @dev Thrown when a spender attempts to transfer tokens with an insufficient allowance.
    error InsufficientAllowance();

    /// @dev Thrown when minting an amount of tokens that would overflow the max tokens.
    error TotalSupplyOverflow();

    /// @dev The unit must be greater than zero and less than `2**96`.
    error InvalidUnit();

    /// @dev Thrown when the caller for a fallback NFT function is not the mirror contract.
    error SenderNotMirror();

    /// @dev Thrown when attempting to transfer tokens to the zero address.
    error TransferToZeroAddress();

    /// @dev Thrown when the mirror address provided for initialization is the zero address.
    error MirrorAddressIsZero();

    /// @dev Thrown when the link call to the mirror contract reverts.
    error LinkMirrorContractFailed();

    /// @dev Thrown when setting an NFT token approval
    /// and the caller is not the owner or an approved operator.
    error ApprovalCallerNotOwnerNorApproved();

    /// @dev Thrown when transferring an NFT
    /// and the caller is not the owner or an approved operator.
    error TransferCallerNotOwnerNorApproved();

    /// @dev Thrown when transferring an NFT and the from address is not the current owner.
    error TransferFromIncorrectOwner();

    /// @dev Thrown when checking the owner or approved address for a non-existent NFT.
    error TokenDoesNotExist();

    /// @dev The function selector is not recognized.
    error FnSelectorNotRecognized();

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                         CONSTANTS                          */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev The flag to denote that the skip NFT flag is initialized.
    uint8 internal constant _ADDRESS_DATA_SKIP_NFT_INITIALIZED_FLAG = 1 << 0;

    /// @dev The flag to denote that the address should skip NFTs.
    uint8 internal constant _ADDRESS_DATA_SKIP_NFT_FLAG = 1 << 1;

    /// @dev The flag to denote that the address has overridden the default Permit2 allowance.
    uint8 internal constant _ADDRESS_DATA_OVERRIDE_PERMIT2_FLAG = 1 << 2;

    /// @dev The canonical Permit2 address.
    /// For signature-based allowance granting for single transaction ERC20 `transferFrom`.
    /// To enable, override `_givePermit2DefaultInfiniteAllowance()`.
    /// [Github](https://github.com/Uniswap/permit2)
    /// [Etherscan](https://etherscan.io/address/0x000000000022D473030F116dDEE9F6B43aC78BA3)
    address internal constant _PERMIT2 =
        0x000000000022D473030F116dDEE9F6B43aC78BA3;

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                          STORAGE                           */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Struct containing an address's token data and settings.
    struct AddressData {
        // Auxiliary data.
        uint88 aux;
        // Flags for `initialized` and `skipNFT`.
        uint8 flags;
        // The alias for the address. Zero means absence of an alias.
        uint32 addressAlias;
        // The number of NFT tokens.
        uint32 ownedLength;
        // The token balance in wei.
        uint96 balance;
    }

    /// @dev A uint32 map in storage.
    struct Uint32Map {
        uint256 spacer;
    }

    /// @dev A bitmap in storage.
    struct Bitmap {
        uint256 spacer;
    }

    /// @dev A struct to wrap a uint256 in storage.
    struct Uint256Ref {
        uint256 value;
    }

    /// @dev A mapping of an address pair to a Uint256Ref.
    struct AddressPairToUint256RefMap {
        uint256 spacer;
    }

    /// @dev Struct containing the base token contract storage.
    struct DN404Storage {
        // Current number of address aliases assigned.
        uint32 numAliases;
        // Next NFT ID to assign for a mint.
        uint32 nextTokenId;
        // The head of the burned pool.
        uint32 burnedPoolHead;
        // The tail of the burned pool.
        uint32 burnedPoolTail;
        // Total number of NFTs in existence.
        uint32 totalNFTSupply;
        // Total supply of tokens.
        uint96 totalSupply;
        // Address of the NFT mirror contract.
        address mirrorERC721;
        // Mapping of a user alias number to their address.
        mapping(uint32 => address) aliasToAddress;
        // Mapping of user operator approvals for NFTs.
        AddressPairToUint256RefMap operatorApprovals;
        // Mapping of NFT approvals to approved operators.
        mapping(uint256 => address) nftApprovals;
        // Bitmap of whether an non-zero NFT approval may exist.
        Bitmap mayHaveNFTApproval;
        // Bitmap of whether a NFT ID exists. Ignored if `_useExistsLookup()` returns false.
        Bitmap exists;
        // Mapping of user allowances for ERC20 spenders.
        AddressPairToUint256RefMap allowance;
        // Mapping of NFT IDs owned by an address.
        mapping(address => Uint32Map) owned;
        // The pool of burned NFT IDs.
        Uint32Map burnedPool;
        // Even indices: owner aliases. Odd indices: owned indices.
        Uint32Map oo;
        // Mapping of user account AddressData.
        mapping(address => AddressData) addressData;
    }

    /// @dev Returns a storage pointer for DN404Storage.
    function _getDN404Storage()
        internal
        pure
        virtual
        returns (DN404Storage storage $)
    {
        /// @solidity memory-safe-assembly
        assembly {
            // `uint72(bytes9(keccak256("DN404_STORAGE")))`.
            $.slot := 0xa20d6e21d0e5255308 // Truncate to 9 bytes to reduce bytecode size.
        }
    }

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                         INITIALIZER                        */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Initializes the DN404 contract with an
    /// `initialTokenSupply`, `initialTokenOwner` and `mirror` NFT contract address.
    ///
    /// Note: The `initialSupplyOwner` will have their skip NFT status set to true.
    function _initializeDN404(
        uint256 initialTokenSupply,
        address initialSupplyOwner,
        address mirror
    ) internal virtual {
        DN404Storage storage $ = _getDN404Storage();

        unchecked {
            if (_unit() - 1 >= 2 ** 96 - 1) revert InvalidUnit();
        }
        if ($.mirrorERC721 != address(0)) revert DNAlreadyInitialized();
        if (mirror == address(0)) revert MirrorAddressIsZero();

        /// @solidity memory-safe-assembly
        assembly {
            // Make the call to link the mirror contract.
            mstore(0x00, 0x0f4599e5) // `linkMirrorContract(address)`.
            mstore(0x20, caller())
            if iszero(
                and(
                    eq(mload(0x00), 1),
                    call(gas(), mirror, 0, 0x1c, 0x24, 0x00, 0x20)
                )
            ) {
                mstore(0x00, 0xd125259c) // `LinkMirrorContractFailed()`.
                revert(0x1c, 0x04)
            }
        }

        $.nextTokenId = uint32(_toUint(_useOneIndexed()));
        $.mirrorERC721 = mirror;

        if (initialTokenSupply != 0) {
            if (initialSupplyOwner == address(0))
                revert TransferToZeroAddress();
            if (_totalSupplyOverflows(initialTokenSupply))
                revert TotalSupplyOverflow();

            $.totalSupply = uint96(initialTokenSupply);
            AddressData storage initialOwnerAddressData = $.addressData[
                initialSupplyOwner
            ];
            initialOwnerAddressData.balance = uint96(initialTokenSupply);

            /// @solidity memory-safe-assembly
            assembly {
                // Emit the {Transfer} event.
                mstore(0x00, initialTokenSupply)
                log3(
                    0x00,
                    0x20,
                    _TRANSFER_EVENT_SIGNATURE,
                    0,
                    shr(96, shl(96, initialSupplyOwner))
                )
            }

            _setSkipNFT(initialSupplyOwner, true);
        }
    }

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*               BASE UNIT FUNCTION TO OVERRIDE               */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Amount of token balance that is equal to one NFT.
    ///
    /// Note: The return value MUST be kept constant after `_initializeDN404` is called.
    function _unit() internal view virtual returns (uint256) {
        return 10 ** 18;
    }

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*               METADATA FUNCTIONS TO OVERRIDE               */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

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

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

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

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                       CONFIGURABLES                        */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Returns whether the tokens IDs are from `[1..n]` instead of `[0..n-1]`.
    function _useOneIndexed() internal pure virtual returns (bool) {
        return true;
    }

    /// @dev Returns if direct NFT transfers should be used during ERC20 transfers
    /// whenever possible, instead of burning and re-minting.
    function _useDirectTransfersIfPossible()
        internal
        view
        virtual
        returns (bool)
    {
        return true;
    }

    /// @dev Returns if burns should be added to the burn pool.
    /// This returns false by default, which means the NFT IDs are re-minted in a cycle.
    function _addToBurnedPool(
        uint256 totalNFTSupplyAfterBurn,
        uint256 totalSupplyAfterBurn
    ) internal view virtual returns (bool) {
        // Silence unused variable compiler warning.
        totalSupplyAfterBurn = totalNFTSupplyAfterBurn;
        return false;
    }

    /// @dev Returns whether to use the exists bitmap for more efficient
    /// scanning of an empty token ID slot.
    /// Recommended for collections that do not use the burn pool,
    /// and are expected to have nearly all possible NFTs materialized.
    ///
    /// Note: The returned value must be constant after initialization.
    function _useExistsLookup() internal view virtual returns (bool) {
        return true;
    }

    /// @dev Hook that is called after a batch of NFT transfers.
    /// The lengths of `from`, `to`, and `ids` are guaranteed to be the same.
    function _afterNFTTransfers(
        address[] memory from,
        address[] memory to,
        uint256[] memory ids
    ) internal virtual {}

    /// @dev Override this function to return true if `_afterNFTTransfers` is used.
    /// This is to help the compiler avoid producing dead bytecode.
    function _useAfterNFTTransfers() internal virtual returns (bool) {}

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                      ERC20 OPERATIONS                      */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Returns the decimals places of the token. Defaults to 18.
    /// Does not affect DN404's internal calculations.
    /// Will only affect the frontend UI on most protocols.
    function decimals() public view virtual returns (uint8) {
        return 18;
    }

    /// @dev Returns the amount of tokens in existence.
    function totalSupply() public view virtual returns (uint256) {
        return uint256(_getDN404Storage().totalSupply);
    }

    /// @dev Returns the amount of tokens owned by `owner`.
    function balanceOf(address owner) public view virtual returns (uint256) {
        return _getDN404Storage().addressData[owner].balance;
    }

    /// @dev Returns the amount of tokens that `spender` can spend on behalf of `owner`.
    function allowance(
        address owner,
        address spender
    ) public view returns (uint256) {
        if (_givePermit2DefaultInfiniteAllowance() && spender == _PERMIT2) {
            uint8 flags = _getDN404Storage().addressData[owner].flags;
            if ((flags & _ADDRESS_DATA_OVERRIDE_PERMIT2_FLAG) == uint256(0)) {
                return type(uint256).max;
            }
        }
        return _ref(_getDN404Storage().allowance, owner, spender).value;
    }

    /// @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
    ///
    /// Emits a {Approval} event.
    function approve(
        address spender,
        uint256 amount
    ) public virtual returns (bool) {
        _approve(msg.sender, spender, amount);
        return true;
    }

    /// @dev Transfer `amount` tokens from the caller to `to`.
    ///
    /// Will burn sender NFTs if balance after transfer is less than
    /// the amount required to support the current NFT balance.
    ///
    /// Will mint NFTs to `to` if the recipient's new balance supports
    /// additional NFTs ***AND*** the `to` address's skipNFT flag is
    /// set to false.
    ///
    /// Requirements:
    /// - `from` must at least have `amount`.
    ///
    /// Emits a {Transfer} event.
    function transfer(
        address to,
        uint256 amount
    ) public virtual returns (bool) {
        _transfer(msg.sender, to, amount);
        return true;
    }

    /// @dev Transfers `amount` tokens from `from` to `to`.
    ///
    /// Note: Does not update the allowance if it is the maximum uint256 value.
    ///
    /// Will burn sender NFTs if balance after transfer is less than
    /// the amount required to support the current NFT balance.
    ///
    /// Will mint NFTs to `to` if the recipient's new balance supports
    /// additional NFTs ***AND*** the `to` address's skipNFT flag is
    /// set to false.
    ///
    /// Requirements:
    /// - `from` must at least have `amount`.
    /// - The caller must have at least `amount` of allowance to transfer the tokens of `from`.
    ///
    /// Emits a {Transfer} event.
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) public virtual returns (bool) {
        Uint256Ref storage a = _ref(
            _getDN404Storage().allowance,
            from,
            msg.sender
        );

        uint256 allowed = _givePermit2DefaultInfiniteAllowance() &&
            msg.sender == _PERMIT2 &&
            (_getDN404Storage().addressData[from].flags &
                _ADDRESS_DATA_OVERRIDE_PERMIT2_FLAG) ==
            uint256(0)
            ? type(uint256).max
            : a.value;

        if (allowed != type(uint256).max) {
            if (amount > allowed) revert InsufficientAllowance();
            unchecked {
                a.value = allowed - amount;
            }
        }
        _transfer(from, to, amount);
        return true;
    }

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                          PERMIT2                           */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Whether Permit2 has infinite allowances by default for all owners.
    /// For signature-based allowance granting for single transaction ERC20 `transferFrom`.
    /// To enable, override this function to return true.
    ///
    /// Note: The returned value SHOULD be kept constant.
    /// If the returned value changes from false to true,
    /// it can override the user customized allowances for Permit2 to infinity.
    function _givePermit2DefaultInfiniteAllowance()
        internal
        view
        virtual
        returns (bool)
    {
        return false;
    }

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                  INTERNAL MINT FUNCTIONS                   */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Mints `amount` tokens to `to`, increasing the total supply.
    ///
    /// Will mint NFTs to `to` if the recipient's new balance supports
    /// additional NFTs ***AND*** the `to` address's skipNFT flag is set to false.
    ///
    /// Note:
    /// - May mint more NFTs than `amount / _unit()`.
    ///   The number of NFTs minted is what is needed to make `to`'s NFT balance whole.
    /// - Token IDs wraps back to `_toUint(_useOneIndexed())` upon exceeding the upper limit.
    ///
    /// Emits a {Transfer} event.
    function _mint(address to, uint256 amount) internal virtual {
        if (to == address(0)) revert TransferToZeroAddress();

        DN404Storage storage $ = _getDN404Storage();
        if ($.mirrorERC721 == address(0)) revert DNNotInitialized();
        AddressData storage toAddressData = $.addressData[to];

        _DNMintTemps memory t;
        unchecked {
            {
                uint256 toBalance = uint256(toAddressData.balance) + amount;
                toAddressData.balance = uint96(toBalance);
                t.toEnd = toBalance / _unit();
            }
            uint256 idLimit;
            {
                uint256 newTotalSupply = uint256($.totalSupply) + amount;
                $.totalSupply = uint96(newTotalSupply);
                uint256 overflows = _toUint(
                    _totalSupplyOverflows(newTotalSupply)
                );
                if (overflows | _toUint(newTotalSupply < amount) != 0)
                    revert TotalSupplyOverflow();
                idLimit = newTotalSupply / _unit();
            }
            while (!getSkipNFT(to)) {
                Uint32Map storage toOwned = $.owned[to];
                Uint32Map storage oo = $.oo;
                uint256 toIndex = toAddressData.ownedLength;
                if (
                    (t.numNFTMints = _zeroFloorSub(t.toEnd, toIndex)) ==
                    uint256(0)
                ) break;

                t.packedLogs = _packedLogsMalloc(t.numNFTMints);
                _packedLogsSet(t.packedLogs, to, 0);
                $.totalNFTSupply += uint32(t.numNFTMints);
                toAddressData.ownedLength = uint32(t.toEnd);
                t.toAlias = _registerAndResolveAlias(toAddressData, to);
                uint32 burnedPoolHead = $.burnedPoolHead;
                t.burnedPoolTail = $.burnedPoolTail;
                t.nextTokenId = _wrapNFTId($.nextTokenId, idLimit);
                // Mint loop.
                do {
                    uint256 id;
                    if (burnedPoolHead != t.burnedPoolTail) {
                        id = _get($.burnedPool, burnedPoolHead++);
                    } else {
                        id = t.nextTokenId;
                        while (_get(oo, _ownershipIndex(id)) != 0) {
                            id = _useExistsLookup()
                                ? _wrapNFTId(
                                    _findFirstUnset($.exists, id + 1, idLimit),
                                    idLimit
                                )
                                : _wrapNFTId(id + 1, idLimit);
                        }
                        t.nextTokenId = _wrapNFTId(id + 1, idLimit);
                    }
                    if (_useExistsLookup()) _set($.exists, id, true);
                    _set(toOwned, toIndex, uint32(id));
                    _setOwnerAliasAndOwnedIndex(
                        oo,
                        id,
                        t.toAlias,
                        uint32(toIndex++)
                    );
                    _packedLogsAppend(t.packedLogs, id);
                } while (toIndex != t.toEnd);

                $.nextTokenId = uint32(t.nextTokenId);
                $.burnedPoolHead = burnedPoolHead;
                _packedLogsSend(t.packedLogs, $);
                break;
            }
        }
        /// @solidity memory-safe-assembly
        assembly {
            // Emit the {Transfer} event.
            mstore(0x00, amount)
            log3(0x00, 0x20, _TRANSFER_EVENT_SIGNATURE, 0, shr(96, shl(96, to)))
        }
        if (_useAfterNFTTransfers()) {
            _afterNFTTransfers(
                _zeroAddresses(t.numNFTMints),
                _filled(t.numNFTMints, to),
                _packedLogsIds(t.packedLogs)
            );
        }
    }

    /// @dev Mints `amount` tokens to `to`, increasing the total supply.
    /// This variant mints NFT tokens starting from ID
    /// `preTotalSupply / _unit() + _toUint(_useOneIndexed())`.
    /// The `nextTokenId` will not be changed.
    /// If any NFTs are minted, the burned pool will be invalidated (emptied).
    ///
    /// Will mint NFTs to `to` if the recipient's new balance supports
    /// additional NFTs ***AND*** the `to` address's skipNFT flag is set to false.
    ///
    /// Note:
    /// - May mint more NFTs than `amount / _unit()`.
    ///   The number of NFTs minted is what is needed to make `to`'s NFT balance whole.
    /// - Token IDs wraps back to `_toUint(_useOneIndexed())` upon exceeding the upper limit.
    ///
    /// Emits a {Transfer} event.
    function _mintNext(address to, uint256 amount) internal virtual {
        if (to == address(0)) revert TransferToZeroAddress();

        DN404Storage storage $ = _getDN404Storage();
        if ($.mirrorERC721 == address(0)) revert DNNotInitialized();
        AddressData storage toAddressData = $.addressData[to];

        _DNMintTemps memory t;
        unchecked {
            {
                uint256 toBalance = uint256(toAddressData.balance) + amount;
                toAddressData.balance = uint96(toBalance);
                t.toEnd = toBalance / _unit();
            }
            uint256 id;
            uint256 idLimit;
            {
                uint256 preTotalSupply = uint256($.totalSupply);
                uint256 newTotalSupply = uint256(preTotalSupply) + amount;
                $.totalSupply = uint96(newTotalSupply);
                uint256 overflows = _toUint(
                    _totalSupplyOverflows(newTotalSupply)
                );
                if (overflows | _toUint(newTotalSupply < amount) != 0)
                    revert TotalSupplyOverflow();
                idLimit = newTotalSupply / _unit();
                id = _wrapNFTId(
                    preTotalSupply / _unit() + _toUint(_useOneIndexed()),
                    idLimit
                );
            }
            while (!getSkipNFT(to)) {
                Uint32Map storage toOwned = $.owned[to];
                Uint32Map storage oo = $.oo;
                uint256 toIndex = toAddressData.ownedLength;
                if (
                    (t.numNFTMints = _zeroFloorSub(t.toEnd, toIndex)) ==
                    uint256(0)
                ) break;

                t.packedLogs = _packedLogsMalloc(t.numNFTMints);
                // Invalidate (empty) the burned pool.
                $.burnedPoolHead = 0;
                $.burnedPoolTail = 0;
                _packedLogsSet(t.packedLogs, to, 0);
                $.totalNFTSupply += uint32(t.numNFTMints);
                toAddressData.ownedLength = uint32(t.toEnd);
                t.toAlias = _registerAndResolveAlias(toAddressData, to);
                // Mint loop.
                do {
                    while (_get(oo, _ownershipIndex(id)) != 0) {
                        id = _useExistsLookup()
                            ? _wrapNFTId(
                                _findFirstUnset($.exists, id + 1, idLimit),
                                idLimit
                            )
                            : _wrapNFTId(id + 1, idLimit);
                    }
                    if (_useExistsLookup()) _set($.exists, id, true);
                    _set(toOwned, toIndex, uint32(id));
                    _setOwnerAliasAndOwnedIndex(
                        oo,
                        id,
                        t.toAlias,
                        uint32(toIndex++)
                    );
                    _packedLogsAppend(t.packedLogs, id);
                    id = _wrapNFTId(id + 1, idLimit);
                } while (toIndex != t.toEnd);

                _packedLogsSend(t.packedLogs, $);
                break;
            }
        }
        /// @solidity memory-safe-assembly
        assembly {
            // Emit the {Transfer} event.
            mstore(0x00, amount)
            log3(0x00, 0x20, _TRANSFER_EVENT_SIGNATURE, 0, shr(96, shl(96, to)))
        }
        if (_useAfterNFTTransfers()) {
            _afterNFTTransfers(
                _zeroAddresses(t.numNFTMints),
                _filled(t.numNFTMints, to),
                _packedLogsIds(t.packedLogs)
            );
        }
    }

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                  INTERNAL BURN FUNCTIONS                   */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Burns `amount` tokens from `from`, reducing the total supply.
    ///
    /// Will burn sender NFTs if balance after transfer is less than
    /// the amount required to support the current NFT balance.
    ///
    /// Emits a {Transfer} event.
    function _burn(address from, uint256 amount) internal virtual {
        DN404Storage storage $ = _getDN404Storage();
        if ($.mirrorERC721 == address(0)) revert DNNotInitialized();

        AddressData storage fromAddressData = $.addressData[from];
        _DNBurnTemps memory t;

        unchecked {
            t.fromBalance = fromAddressData.balance;
            if (amount > t.fromBalance) revert InsufficientBalance();

            fromAddressData.balance = uint96(t.fromBalance -= amount);
            t.totalSupply = uint256($.totalSupply) - amount;
            $.totalSupply = uint96(t.totalSupply);

            Uint32Map storage fromOwned = $.owned[from];
            uint256 fromIndex = fromAddressData.ownedLength;
            t.numNFTBurns = _zeroFloorSub(fromIndex, t.fromBalance / _unit());

            if (t.numNFTBurns != 0) {
                t.packedLogs = _packedLogsMalloc(t.numNFTBurns);
                _packedLogsSet(t.packedLogs, from, 1);
                bool addToBurnedPool;
                {
                    uint256 totalNFTSupply = uint256($.totalNFTSupply) -
                        t.numNFTBurns;
                    $.totalNFTSupply = uint32(totalNFTSupply);
                    addToBurnedPool = _addToBurnedPool(
                        totalNFTSupply,
                        t.totalSupply
                    );
                }

                Uint32Map storage oo = $.oo;
                uint256 fromEnd = fromIndex - t.numNFTBurns;
                fromAddressData.ownedLength = uint32(fromEnd);
                uint32 burnedPoolTail = $.burnedPoolTail;
                // Burn loop.
                do {
                    uint256 id = _get(fromOwned, --fromIndex);
                    _setOwnerAliasAndOwnedIndex(oo, id, 0, 0);
                    _packedLogsAppend(t.packedLogs, id);
                    if (_useExistsLookup()) _set($.exists, id, false);
                    if (addToBurnedPool)
                        _set($.burnedPool, burnedPoolTail++, uint32(id));
                    if (_get($.mayHaveNFTApproval, id)) {
                        _set($.mayHaveNFTApproval, id, false);
                        delete $.nftApprovals[id];
                    }
                } while (fromIndex != fromEnd);

                if (addToBurnedPool) $.burnedPoolTail = burnedPoolTail;
                _packedLogsSend(t.packedLogs, $);
            }
        }
        /// @solidity memory-safe-assembly
        assembly {
            // Emit the {Transfer} event.
            mstore(0x00, amount)
            log3(
                0x00,
                0x20,
                _TRANSFER_EVENT_SIGNATURE,
                shr(96, shl(96, from)),
                0
            )
        }
        if (_useAfterNFTTransfers()) {
            _afterNFTTransfers(
                _filled(t.numNFTBurns, from),
                _zeroAddresses(t.numNFTBurns),
                _packedLogsIds(t.packedLogs)
            );
        }
    }

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                INTERNAL TRANSFER FUNCTIONS                 */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Moves `amount` of tokens from `from` to `to`.
    ///
    /// Will burn sender NFTs if balance after transfer is less than
    /// the amount required to support the current NFT balance.
    ///
    /// Will mint NFTs to `to` if the recipient's new balance supports
    /// additional NFTs ***AND*** the `to` address's skipNFT flag is
    /// set to false.
    ///
    /// Emits a {Transfer} event.
    function _transfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {
        if (to == address(0)) revert TransferToZeroAddress();

        DN404Storage storage $ = _getDN404Storage();
        AddressData storage fromAddressData = $.addressData[from];
        AddressData storage toAddressData = $.addressData[to];
        if ($.mirrorERC721 == address(0)) revert DNNotInitialized();

        _DNTransferTemps memory t;
        t.fromOwnedLength = fromAddressData.ownedLength;
        t.toOwnedLength = toAddressData.ownedLength;

        unchecked {
            {
                uint256 fromBalance = fromAddressData.balance;
                if (amount > fromBalance) revert InsufficientBalance();
                fromAddressData.balance = uint96(fromBalance -= amount);

                uint256 toBalance = uint256(toAddressData.balance) + amount;
                toAddressData.balance = uint96(toBalance);
                t.numNFTBurns = _zeroFloorSub(
                    t.fromOwnedLength,
                    fromBalance / _unit()
                );

                if (!getSkipNFT(to)) {
                    if (from == to)
                        t.toOwnedLength = t.fromOwnedLength - t.numNFTBurns;
                    t.numNFTMints = _zeroFloorSub(
                        toBalance / _unit(),
                        t.toOwnedLength
                    );
                }
            }

            while (_useDirectTransfersIfPossible()) {
                uint256 n = _min(
                    t.fromOwnedLength,
                    _min(t.numNFTBurns, t.numNFTMints)
                );
                if (n == uint256(0)) break;
                t.numNFTBurns -= n;
                t.numNFTMints -= n;
                if (from == to) {
                    t.toOwnedLength += n;
                    break;
                }
                t.directLogs = _directLogsMalloc(n, from, to);
                Uint32Map storage fromOwned = $.owned[from];
                Uint32Map storage toOwned = $.owned[to];
                t.toAlias = _registerAndResolveAlias(toAddressData, to);
                uint256 toIndex = t.toOwnedLength;
                n = toIndex + n;
                // Direct transfer loop.
                do {
                    uint256 id = _get(fromOwned, --t.fromOwnedLength);
                    _set(toOwned, toIndex, uint32(id));
                    _setOwnerAliasAndOwnedIndex(
                        $.oo,
                        id,
                        t.toAlias,
                        uint32(toIndex)
                    );
                    _directLogsAppend(t.directLogs, id);
                    if (_get($.mayHaveNFTApproval, id)) {
                        _set($.mayHaveNFTApproval, id, false);
                        delete $.nftApprovals[id];
                    }
                } while (++toIndex != n);

                toAddressData.ownedLength = uint32(t.toOwnedLength = toIndex);
                fromAddressData.ownedLength = uint32(t.fromOwnedLength);
                break;
            }

            t.totalNFTSupply =
                uint256($.totalNFTSupply) +
                t.numNFTMints -
                t.numNFTBurns;
            $.totalNFTSupply = uint32(t.totalNFTSupply);

            Uint32Map storage oo = $.oo;
            t.packedLogs = _packedLogsMalloc(t.numNFTBurns + t.numNFTMints);

            t.burnedPoolTail = $.burnedPoolTail;
            if (t.numNFTBurns != 0) {
                _packedLogsSet(t.packedLogs, from, 1);
                bool addToBurnedPool = _addToBurnedPool(
                    t.totalNFTSupply,
                    $.totalSupply
                );
                Uint32Map storage fromOwned = $.owned[from];
                uint256 fromIndex = t.fromOwnedLength;
                fromAddressData.ownedLength = uint32(
                    t.fromEnd = fromIndex - t.numNFTBurns
                );
                uint32 burnedPoolTail = t.burnedPoolTail;
                // Burn loop.
                do {
                    uint256 id = _get(fromOwned, --fromIndex);
                    _setOwnerAliasAndOwnedIndex(oo, id, 0, 0);
                    _packedLogsAppend(t.packedLogs, id);
                    if (_useExistsLookup()) _set($.exists, id, false);
                    if (addToBurnedPool)
                        _set($.burnedPool, burnedPoolTail++, uint32(id));
                    if (_get($.mayHaveNFTApproval, id)) {
                        _set($.mayHaveNFTApproval, id, false);
                        delete $.nftApprovals[id];
                    }
                } while (fromIndex != t.fromEnd);

                if (addToBurnedPool)
                    $.burnedPoolTail = (t.burnedPoolTail = burnedPoolTail);
            }

            if (t.numNFTMints != 0) {
                _packedLogsSet(t.packedLogs, to, 0);
                Uint32Map storage toOwned = $.owned[to];
                t.toAlias = _registerAndResolveAlias(toAddressData, to);
                uint256 idLimit = $.totalSupply / _unit();
                t.nextTokenId = _wrapNFTId($.nextTokenId, idLimit);
                uint256 toIndex = t.toOwnedLength;
                toAddressData.ownedLength = uint32(
                    t.toEnd = toIndex + t.numNFTMints
                );
                uint32 burnedPoolHead = $.burnedPoolHead;
                // Mint loop.
                do {
                    uint256 id;
                    if (burnedPoolHead != t.burnedPoolTail) {
                        id = _get($.burnedPool, burnedPoolHead++);
                    } else {
                        id = t.nextTokenId;
                        while (_get(oo, _ownershipIndex(id)) != 0) {
                            id = _useExistsLookup()
                                ? _wrapNFTId(
                                    _findFirstUnset($.exists, id + 1, idLimit),
                                    idLimit
                                )
                                : _wrapNFTId(id + 1, idLimit);
                        }
                        t.nextTokenId = _wrapNFTId(id + 1, idLimit);
                    }
                    if (_useExistsLookup()) _set($.exists, id, true);
                    _set(toOwned, toIndex, uint32(id));
                    _setOwnerAliasAndOwnedIndex(
                        oo,
                        id,
                        t.toAlias,
                        uint32(toIndex++)
                    );
                    _packedLogsAppend(t.packedLogs, id);
                } while (toIndex != t.toEnd);

                $.burnedPoolHead = burnedPoolHead;
                $.nextTokenId = uint32(t.nextTokenId);
            }

            if (t.directLogs != bytes32(0)) _directLogsSend(t.directLogs, $);
            if (t.packedLogs != bytes32(0)) _packedLogsSend(t.packedLogs, $);
        }
        /// @solidity memory-safe-assembly
        assembly {
            // Emit the {Transfer} event.
            mstore(0x00, amount)
            // forgefmt: disable-next-item
            log3(
                0x00,
                0x20,
                _TRANSFER_EVENT_SIGNATURE,
                shr(96, shl(96, from)),
                shr(96, shl(96, to))
            )
        }
        if (_useAfterNFTTransfers()) {
            uint256[] memory ids = _directLogsIds(t.directLogs);
            unchecked {
                _afterNFTTransfers(
                    _concat(
                        _filled(ids.length + t.numNFTBurns, from),
                        _zeroAddresses(t.numNFTMints)
                    ),
                    _concat(
                        _concat(
                            _filled(ids.length, to),
                            _zeroAddresses(t.numNFTBurns)
                        ),
                        _filled(t.numNFTMints, to)
                    ),
                    _concat(ids, _packedLogsIds(t.packedLogs))
                );
            }
        }
    }

    /// @dev Transfers token `id` from `from` to `to`.
    /// Also emits an ERC721 {Transfer} event on the `mirrorERC721`.
    ///
    /// Requirements:
    ///
    /// - Token `id` must exist.
    /// - `from` must be the owner of the token.
    /// - `to` cannot be the zero address.
    /// - `msgSender` must be the owner of the token, or be approved to manage the token.
    ///
    /// Emits a {Transfer} event.
    function _initiateTransferFromNFT(
        address from,
        address to,
        uint256 id,
        address msgSender
    ) internal virtual {
        // Emit ERC721 {Transfer} event.
        // We do this before the `_transferFromNFT`, as `_transferFromNFT` may use
        // the `_afterNFTTransfers` hook, which may trigger more transfers.
        // This helps keeps the sequence of emitted events consistent.
        // Since `mirrorERC721` is a trusted contract, we can do this.
        bytes32 directLogs = _directLogsMalloc(1, from, to);
        _directLogsAppend(directLogs, id);
        _directLogsSend(directLogs, _getDN404Storage());

        _transferFromNFT(from, to, id, msgSender);
    }

    /// @dev Transfers token `id` from `from` to `to`.
    ///
    /// This function will be called when a ERC721 transfer is made on the mirror contract.
    ///
    /// Requirements:
    ///
    /// - Token `id` must exist.
    /// - `from` must be the owner of the token.
    /// - `to` cannot be the zero address.
    /// - `msgSender` must be the owner of the token, or be approved to manage the token.
    ///
    /// Emits a {Transfer} event.
    function _transferFromNFT(
        address from,
        address to,
        uint256 id,
        address msgSender
    ) internal virtual {
        if (to == address(0)) revert TransferToZeroAddress();

        DN404Storage storage $ = _getDN404Storage();
        if ($.mirrorERC721 == address(0)) revert DNNotInitialized();

        Uint32Map storage oo = $.oo;

        if (
            from !=
            $.aliasToAddress[_get(oo, _ownershipIndex(_restrictNFTId(id)))]
        ) {
            revert TransferFromIncorrectOwner();
        }

        if (msgSender != from) {
            if (!_isApprovedForAll(from, msgSender)) {
                if (_getApproved(id) != msgSender) {
                    revert TransferCallerNotOwnerNorApproved();
                }
            }
        }

        AddressData storage fromAddressData = $.addressData[from];
        AddressData storage toAddressData = $.addressData[to];

        uint256 unit = _unit();
        mapping(address => Uint32Map) storage owned = $.owned;

        unchecked {
            uint256 fromBalance = fromAddressData.balance;
            if (unit > fromBalance) revert InsufficientBalance();
            fromAddressData.balance = uint96(fromBalance - unit);
            toAddressData.balance += uint96(unit);
        }
        if (_get($.mayHaveNFTApproval, id)) {
            _set($.mayHaveNFTApproval, id, false);
            delete $.nftApprovals[id];
        }
        unchecked {
            Uint32Map storage fromOwned = owned[from];
            uint32 updatedId = _get(fromOwned, --fromAddressData.ownedLength);
            uint32 i = _get(oo, _ownedIndex(id));
            _set(fromOwned, i, updatedId);
            _set(oo, _ownedIndex(updatedId), i);
        }
        unchecked {
            uint32 n = toAddressData.ownedLength++;
            _set(owned[to], n, uint32(id));
            _setOwnerAliasAndOwnedIndex(
                oo,
                id,
                _registerAndResolveAlias(toAddressData, to),
                n
            );
        }
        /// @solidity memory-safe-assembly
        assembly {
            // Emit the {Transfer} event.
            mstore(0x00, unit)
            // forgefmt: disable-next-item
            log3(
                0x00,
                0x20,
                _TRANSFER_EVENT_SIGNATURE,
                shr(96, shl(96, from)),
                shr(96, shl(96, to))
            )
        }
        if (_useAfterNFTTransfers()) {
            _afterNFTTransfers(
                _filled(1, from),
                _filled(1, to),
                _filled(1, id)
            );
        }
    }

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                 INTERNAL APPROVE FUNCTIONS                 */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Sets `amount` as the allowance of `spender` over the tokens of `owner`.
    ///
    /// Emits a {Approval} event.
    function _approve(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        if (_givePermit2DefaultInfiniteAllowance() && spender == _PERMIT2) {
            _getDN404Storage()
                .addressData[owner]
                .flags |= _ADDRESS_DATA_OVERRIDE_PERMIT2_FLAG;
        }
        _ref(_getDN404Storage().allowance, owner, spender).value = amount;
        /// @solidity memory-safe-assembly
        assembly {
            // Emit the {Approval} event.
            mstore(0x00, amount)
            // forgefmt: disable-next-item
            log3(
                0x00,
                0x20,
                _APPROVAL_EVENT_SIGNATURE,
                shr(96, shl(96, owner)),
                shr(96, shl(96, spender))
            )
        }
    }

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                 DATA HITCHHIKING FUNCTIONS                 */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @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 (uint88) {
        return _getDN404Storage().addressData[owner].aux;
    }

    /// @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, uint88 value) internal virtual {
        _getDN404Storage().addressData[owner].aux = value;
    }

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                     SKIP NFT FUNCTIONS                     */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Returns true if minting and transferring ERC20s to `owner` will skip minting NFTs.
    /// Returns false otherwise.
    function getSkipNFT(
        address owner
    ) public view virtual returns (bool result) {
        uint8 flags = _getDN404Storage().addressData[owner].flags;
        /// @solidity memory-safe-assembly
        assembly {
            result := iszero(iszero(and(flags, _ADDRESS_DATA_SKIP_NFT_FLAG)))
            if iszero(and(flags, _ADDRESS_DATA_SKIP_NFT_INITIALIZED_FLAG)) {
                result := iszero(iszero(extcodesize(owner)))
            }
        }
    }

    /// @dev Sets the caller's skipNFT flag to `skipNFT`. Returns true.
    ///
    /// Emits a {SkipNFTSet} event.
    function setSkipNFT(bool skipNFT) public virtual returns (bool) {
        _setSkipNFT(msg.sender, skipNFT);
        return true;
    }

    /// @dev Internal function to set account `owner` skipNFT flag to `state`
    ///
    /// Initializes account `owner` AddressData if it is not currently initialized.
    ///
    /// Emits a {SkipNFTSet} event.
    function _setSkipNFT(address owner, bool state) internal virtual {
        AddressData storage d = _getDN404Storage().addressData[owner];
        uint8 flags = d.flags;
        /// @solidity memory-safe-assembly
        assembly {
            let s := xor(
                iszero(and(flags, _ADDRESS_DATA_SKIP_NFT_FLAG)),
                iszero(state)
            )
            flags := xor(mul(_ADDRESS_DATA_SKIP_NFT_FLAG, s), flags)
            flags := or(_ADDRESS_DATA_SKIP_NFT_INITIALIZED_FLAG, flags)
            mstore(0x00, iszero(iszero(state)))
            log2(
                0x00,
                0x20,
                _SKIP_NFT_SET_EVENT_SIGNATURE,
                shr(96, shl(96, owner))
            )
        }
        d.flags = flags;
    }

    /// @dev Returns the `addressAlias` of account `to`.
    ///
    /// Assigns and registers the next alias if `to` alias was not previously registered.
    function _registerAndResolveAlias(
        AddressData storage toAddressData,
        address to
    ) internal virtual returns (uint32 addressAlias) {
        DN404Storage storage $ = _getDN404Storage();
        addressAlias = toAddressData.addressAlias;
        if (addressAlias == uint256(0)) {
            unchecked {
                addressAlias = ++$.numAliases;
            }
            toAddressData.addressAlias = addressAlias;
            $.aliasToAddress[addressAlias] = to;
            if (addressAlias == uint256(0)) revert(); // Overflow.
        }
    }

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                     MIRROR OPERATIONS                      */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Returns the address of the mirror NFT contract.
    function mirrorERC721() public view virtual returns (address) {
        return _getDN404Storage().mirrorERC721;
    }

    /// @dev Returns the total NFT supply.
    function _totalNFTSupply() internal view virtual returns (uint256) {
        return _getDN404Storage().totalNFTSupply;
    }

    /// @dev Returns `owner` NFT balance.
    function _balanceOfNFT(
        address owner
    ) internal view virtual returns (uint256) {
        return _getDN404Storage().addressData[owner].ownedLength;
    }

    /// @dev Returns the owner of token `id`.
    /// Returns the zero address instead of reverting if the token does not exist.
    function _ownerAt(uint256 id) internal view virtual returns (address) {
        DN404Storage storage $ = _getDN404Storage();
        return
            $.aliasToAddress[_get($.oo, _ownershipIndex(_restrictNFTId(id)))];
    }

    /// @dev Returns the owner of token `id`.
    ///
    /// Requirements:
    /// - Token `id` must exist.
    function _ownerOf(uint256 id) internal view virtual returns (address) {
        if (!_exists(id)) revert TokenDoesNotExist();
        return _ownerAt(id);
    }

    /// @dev Returns whether `operator` is approved to manage the NFT tokens of `owner`.
    function _isApprovedForAll(
        address owner,
        address operator
    ) internal view virtual returns (bool) {
        return
            _ref(_getDN404Storage().operatorApprovals, owner, operator).value !=
            0;
    }

    /// @dev Returns if token `id` exists.
    function _exists(uint256 id) internal view virtual returns (bool) {
        return _ownerAt(id) != address(0);
    }

    /// @dev Returns the account approved to manage token `id`.
    ///
    /// Requirements:
    /// - Token `id` must exist.
    function _getApproved(uint256 id) internal view virtual returns (address) {
        if (!_exists(id)) revert TokenDoesNotExist();
        return _getDN404Storage().nftApprovals[id];
    }

    /// @dev Sets `spender` as the approved account to manage token `id`, using `msgSender`.
    ///
    /// Requirements:
    /// - `msgSender` must be the owner or an approved operator for the token owner.
    function _approveNFT(
        address spender,
        uint256 id,
        address msgSender
    ) internal virtual returns (address owner) {
        DN404Storage storage $ = _getDN404Storage();

        owner = $.aliasToAddress[
            _get($.oo, _ownershipIndex(_restrictNFTId(id)))
        ];

        if (msgSender != owner) {
            if (!_isApprovedForAll(owner, msgSender)) {
                revert ApprovalCallerNotOwnerNorApproved();
            }
        }

        $.nftApprovals[id] = spender;
        _set($.mayHaveNFTApproval, id, spender != address(0));
    }

    /// @dev Approve or remove the `operator` as an operator for `msgSender`,
    /// without authorization checks.
    function _setApprovalForAll(
        address operator,
        bool approved,
        address msgSender
    ) internal virtual {
        // For efficiency, we won't check if `operator` isn't `address(0)` (practically a no-op).
        _ref(_getDN404Storage().operatorApprovals, msgSender, operator)
            .value = _toUint(approved);
    }

    /// @dev Returns the NFT IDs of `owner` in the range `[begin..end)` (exclusive of `end`).
    /// `begin` and `end` are indices in the owner's token ID array, not the entire token range.
    /// Optimized for smaller bytecode size, as this function is intended for off-chain calling.
    function _ownedIds(
        address owner,
        uint256 begin,
        uint256 end
    ) internal view virtual returns (uint256[] memory ids) {
        DN404Storage storage $ = _getDN404Storage();
        Uint32Map storage owned = $.owned[owner];
        end = _min($.addressData[owner].ownedLength, end);
        /// @solidity memory-safe-assembly
        assembly {
            ids := mload(0x40)
            let i := begin
            for {

            } lt(i, end) {
                i := add(i, 1)
            } {
                let s := add(shl(96, owned.slot), shr(3, i)) // Storage slot.
                let id := and(0xffffffff, shr(shl(5, and(i, 7)), sload(s)))
                mstore(add(add(ids, 0x20), shl(5, sub(i, begin))), id) // Append to.
            }
            mstore(ids, sub(i, begin)) // Store the length.
            mstore(0x40, add(add(ids, 0x20), shl(5, sub(i, begin)))) // Allocate memory.
        }
    }

    /// @dev Fallback modifier to dispatch calls from the mirror NFT contract
    /// to internal functions in this contract.
    modifier dn404Fallback() virtual {
        DN404Storage storage $ = _getDN404Storage();

        uint256 fnSelector = _calldataload(0x00) >> 224;

        // `transferFromNFT(address,address,uint256,address)`.
        if (fnSelector == 0xe5eb36c8) {
            if (msg.sender != $.mirrorERC721) revert SenderNotMirror();
            _transferFromNFT(
                address(uint160(_calldataload(0x04))), // `from`.
                address(uint160(_calldataload(0x24))), // `to`.
                _calldataload(0x44), // `id`.
                address(uint160(_calldataload(0x64))) // `msgSender`.
            );
            _return(1);
        }
        // `setApprovalForAllNFT(address,bool,address)`.
        if (fnSelector == 0xf6916ddd) {
            if (msg.sender != $.mirrorERC721) revert SenderNotMirror();
            _setApprovalForAll(
                address(uint160(_calldataload(0x04))), // `spender`.
                _calldataload(0x24) != 0, // `status`.
                address(uint160(_calldataload(0x44))) // `msgSender`.
            );
            _return(1);
        }
        // `isApprovedForAllNFT(address,address)`.
        if (fnSelector == 0x62fb246d) {
            bool result = _isApprovedForAll(
                address(uint160(_calldataload(0x04))), // `owner`.
                address(uint160(_calldataload(0x24))) // `operator`.
            );
            _return(_toUint(result));
        }
        // `ownerOfNFT(uint256)`.
        if (fnSelector == 0x2d8a746e) {
            _return(uint160(_ownerOf(_calldataload(0x04))));
        }
        // `ownerAtNFT(uint256)`.
        if (fnSelector == 0xc016aa52) {
            _return(uint160(_ownerAt(_calldataload(0x04))));
        }
        // `approveNFT(address,uint256,address)`.
        if (fnSelector == 0xd10b6e0c) {
            if (msg.sender != $.mirrorERC721) revert SenderNotMirror();
            address owner = _approveNFT(
                address(uint160(_calldataload(0x04))), // `spender`.
                _calldataload(0x24), // `id`.
                address(uint160(_calldataload(0x44))) // `msgSender`.
            );
            _return(uint160(owner));
        }
        // `getApprovedNFT(uint256)`.
        if (fnSelector == 0x27ef5495) {
            _return(uint160(_getApproved(_calldataload(0x04))));
        }
        // `balanceOfNFT(address)`.
        if (fnSelector == 0xf5b100ea) {
            _return(_balanceOfNFT(address(uint160(_calldataload(0x04)))));
        }
        // `totalNFTSupply()`.
        if (fnSelector == 0xe2c79281) {
            _return(_totalNFTSupply());
        }
        // `tokenURINFT(uint256)`.
        if (fnSelector == 0xcb30b460) {
            /// @solidity memory-safe-assembly
            assembly {
                mstore(0x40, add(mload(0x40), 0x20))
            }
            string memory uri = _tokenURI(_calldataload(0x04));
            /// @solidity memory-safe-assembly
            assembly {
                // Memory safe, as we've advanced the free memory pointer by a word.
                let o := sub(uri, 0x20) // Start of the returndata.
                let z := add(mload(uri), 0x40) // Unpadded length of returndata.
                mstore(add(o, z), 0) // Zeroize the word after the end of the string.
                mstore(o, 0x20) // Store the offset of `uri`.
                return(o, and(not(0x1f), add(0x1f, z)))
            }
        }
        // `implementsDN404()`.
        if (fnSelector == 0xb7a94eb8) {
            _return(1);
        }
        _;
    }

    /// @dev Fallback function for calls from mirror NFT contract.
    /// Override this if you need to implement your custom
    /// fallback with utilities like Solady's `LibZip.cdFallback()`.
    /// And always remember to always wrap the fallback with `dn404Fallback`.
    fallback() external payable virtual dn404Fallback {
        revert FnSelectorNotRecognized(); // Not mandatory. Just for quality of life.
    }

    /// @dev This is to silence the compiler warning.
    /// Override and remove the revert if you want your contract to receive ETH via receive.
    receive() external payable virtual {
        if (msg.value != 0) revert();
    }

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                 INTERNAL / PRIVATE HELPERS                 */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Returns `(i - _toUint(_useOneIndexed())) << 1`.
    function _ownershipIndex(uint256 i) internal pure returns (uint256) {
        unchecked {
            return (i - _toUint(_useOneIndexed())) << 1;
        }
    }

    /// @dev Returns `((i - _toUint(_useOneIndexed())) << 1) + 1`.
    function _ownedIndex(uint256 i) internal pure returns (uint256) {
        unchecked {
            return ((i - _toUint(_useOneIndexed())) << 1) + 1;
        }
    }

    /// @dev Returns the uint32 value at `index` in `map`.
    function _get(
        Uint32Map storage map,
        uint256 index
    ) internal view returns (uint32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            let s := add(shl(96, map.slot), shr(3, index)) // Storage slot.
            result := and(0xffffffff, shr(shl(5, and(index, 7)), sload(s)))
        }
    }

    /// @dev Updates the uint32 value at `index` in `map`.
    function _set(Uint32Map storage map, uint256 index, uint32 value) internal {
        /// @solidity memory-safe-assembly
        assembly {
            let s := add(shl(96, map.slot), shr(3, index)) // Storage slot.
            let o := shl(5, and(index, 7)) // Storage slot offset (bits).
            let v := sload(s) // Storage slot value.
            sstore(s, xor(v, shl(o, and(0xffffffff, xor(value, shr(o, v))))))
        }
    }

    /// @dev Sets the owner alias and the owned index together.
    function _setOwnerAliasAndOwnedIndex(
        Uint32Map storage map,
        uint256 id,
        uint32 ownership,
        uint32 ownedIndex
    ) internal {
        uint256 t = _toUint(_useOneIndexed());
        /// @solidity memory-safe-assembly
        assembly {
            let i := sub(id, t) // Index of the uint64 combined value.
            let s := add(shl(96, map.slot), shr(2, i)) // Storage slot.
            let v := sload(s) // Storage slot value.
            let o := shl(6, and(i, 3)) // Storage slot offset (bits).
            let combined := or(shl(32, ownedIndex), and(0xffffffff, ownership))
            sstore(
                s,
                xor(
                    v,
                    shl(o, and(0xffffffffffffffff, xor(shr(o, v), combined)))
                )
            )
        }
    }

    /// @dev Returns the boolean value of the bit at `index` in `bitmap`.
    function _get(
        Bitmap storage bitmap,
        uint256 index
    ) internal view returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            let s := add(shl(96, bitmap.slot), shr(8, index)) // Storage slot.
            result := and(1, shr(and(0xff, index), sload(s)))
        }
    }

    /// @dev Updates the bit at `index` in `bitmap` to `value`.
    function _set(Bitmap storage bitmap, uint256 index, bool value) internal {
        /// @solidity memory-safe-assembly
        assembly {
            let s := add(shl(96, bitmap.slot), shr(8, index)) // Storage slot.
            let o := and(0xff, index) // Storage slot offset (bits).
            sstore(
                s,
                or(and(sload(s), not(shl(o, 1))), shl(o, iszero(iszero(value))))
            )
        }
    }

    /// @dev Returns the index of the least significant unset bit in `[begin..upTo]`.
    /// If no unset bit is found, returns `type(uint256).max`.
    function _findFirstUnset(
        Bitmap storage bitmap,
        uint256 begin,
        uint256 upTo
    ) internal view returns (uint256 unsetBitIndex) {
        /// @solidity memory-safe-assembly
        assembly {
            unsetBitIndex := not(0) // Initialize to `type(uint256).max`.
            let s := shl(96, bitmap.slot) // Storage offset of the bitmap.
            let bucket := add(s, shr(8, begin))
            let negBits := shl(
                and(0xff, begin),
                shr(and(0xff, begin), not(sload(bucket)))
            )
            if iszero(negBits) {
                let lastBucket := add(s, shr(8, upTo))
                for {

                } 1 {

                } {
                    bucket := add(bucket, 1)
                    negBits := not(sload(bucket))
                    if or(negBits, gt(bucket, lastBucket)) {
                        break
                    }
                }
                if gt(bucket, lastBucket) {
                    negBits := shr(
                        and(0xff, not(upTo)),
                        shl(and(0xff, not(upTo)), negBits)
                    )
                }
            }
            if negBits {
                // Find-first-set routine.
                // From: https://github.com/vectorized/solady/blob/main/src/utils/LibBit.sol
                let b := and(negBits, add(not(negBits), 1)) // Isolate the least significant bit.
                // For the upper 3 bits of the result, use a De Bruijn-like lookup.
                // Credit to adhusson: https://blog.adhusson.com/cheap-find-first-set-evm/
                // forgefmt: disable-next-item
                let r := shl(
                    5,
                    shr(
                        252,
                        shl(
                            shl(
                                2,
                                shr(
                                    250,
                                    mul(
                                        b,
                                        0x2aaaaaaaba69a69a6db6db6db2cb2cb2ce739ce73def7bdeffffffff
                                    )
                                )
                            ),
                            0x1412563212c14164235266736f7425221143267a45243675267677
                        )
                    )
                )
                // For the lower 5 bits of the result, use a De Bruijn lookup.
                // forgefmt: disable-next-item
                r := or(
                    r,
                    byte(
                        and(div(0xd76453e0, shr(r, b)), 0x1f),
                        0x001f0d1e100c1d070f090b19131c1706010e11080a1a141802121b1503160405
                    )
                )
                r := or(shl(8, sub(bucket, s)), r)
                unsetBitIndex := or(r, sub(0, or(gt(r, upTo), lt(r, begin))))
            }
        }
    }

    /// @dev Returns a storage reference to the value at (`a0`, `a1`) in `map`.
    function _ref(
        AddressPairToUint256RefMap storage map,
        address a0,
        address a1
    ) internal pure returns (Uint256Ref storage ref) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x28, a1)
            mstore(0x14, a0)
            mstore(0x00, map.slot)
            ref.slot := keccak256(0x00, 0x48)
            // Clear the part of the free memory pointer that was overwritten.
            mstore(0x28, 0x00)
        }
    }

    /// @dev Wraps the NFT ID.
    function _wrapNFTId(
        uint256 id,
        uint256 idLimit
    ) internal pure returns (uint256 result) {
        result = _toUint(_useOneIndexed());
        /// @solidity memory-safe-assembly
        assembly {
            result := or(
                mul(
                    or(mul(iszero(gt(id, idLimit)), id), gt(id, idLimit)),
                    result
                ),
                mul(mul(lt(id, idLimit), id), iszero(result))
            )
        }
    }

    /// @dev Returns `id > type(uint32).max ? 0 : id`.
    function _restrictNFTId(uint256 id) internal pure returns (uint256 result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := mul(id, lt(id, 0x100000000))
        }
    }

    /// @dev Returns whether `amount` is an invalid `totalSupply`.
    function _totalSupplyOverflows(
        uint256 amount
    ) internal view returns (bool result) {
        uint256 unit = _unit();
        /// @solidity memory-safe-assembly
        assembly {
            result := iszero(
                iszero(or(shr(96, amount), lt(0xfffffffe, div(amount, unit))))
            )
        }
    }

    /// @dev Returns `max(0, x - y)`.
    function _zeroFloorSub(
        uint256 x,
        uint256 y
    ) internal pure returns (uint256 z) {
        /// @solidity memory-safe-assembly
        assembly {
            z := mul(gt(x, y), sub(x, y))
        }
    }

    /// @dev Returns `x < y ? x : y`.
    function _min(uint256 x, uint256 y) internal pure returns (uint256 z) {
        /// @solidity memory-safe-assembly
        assembly {
            z := xor(x, mul(xor(x, y), lt(y, x)))
        }
    }

    /// @dev Returns `b ? 1 : 0`.
    function _toUint(bool b) internal pure returns (uint256 result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := iszero(iszero(b))
        }
    }

    /// @dev Initiates memory allocation for direct logs with `n` log items.
    function _directLogsMalloc(
        uint256 n,
        address from,
        address to
    ) private pure returns (bytes32 p) {
        /// @solidity memory-safe-assembly
        assembly {
            // `p`'s layout:
            //    uint256 offset;
            //    uint256[] logs;
            p := mload(0x40)
            let m := add(p, 0x40)
            mstore(m, 0x144027d3) // `logDirectTransfer(address,address,uint256[])`.
            mstore(add(m, 0x20), shr(96, shl(96, from)))
            mstore(add(m, 0x40), shr(96, shl(96, to)))
            mstore(add(m, 0x60), 0x60) // Offset of `logs` in the calldata to send.
            // Skip 4 words: `fnSelector`, `from`, `to`, `calldataLogsOffset`.
            let logs := add(0x80, m)
            mstore(logs, n) // Store the length.
            let offset := add(0x20, logs) // Skip the word for `p.logs.length`.
            mstore(0x40, add(offset, shl(5, n))) // Allocate memory.
            mstore(add(0x20, p), logs) // Set `p.logs`.
            mstore(p, offset) // Set `p.offset`.
        }
    }

    /// @dev Adds a direct log item to `p` with token `id`.
    function _directLogsAppend(bytes32 p, uint256 id) private pure {
        /// @solidity memory-safe-assembly
        assembly {
            let offset := mload(p)
            mstore(offset, id)
            mstore(p, add(offset, 0x20))
        }
    }

    /// @dev Calls the `mirror` NFT contract to emit {Transfer} events for packed logs `p`.
    function _directLogsSend(bytes32 p, DN404Storage storage $) private {
        address mirror = $.mirrorERC721;
        /// @solidity memory-safe-assembly
        assembly {
            let logs := mload(add(p, 0x20))
            let n := add(0x84, shl(5, mload(logs))) // Length of calldata to send.
            let o := sub(logs, 0x80) // Start of calldata to send.
            if iszero(
                and(
                    eq(mload(o), 1),
                    call(gas(), mirror, 0, add(o, 0x1c), n, o, 0x20)
                )
            ) {
                revert(o, 0x00)
            }
        }
    }

    /// @dev Returns the token IDs of the direct logs.
    function _directLogsIds(
        bytes32 p
    ) private pure returns (uint256[] memory ids) {
        /// @solidity memory-safe-assembly
        assembly {
            if p {
                ids := mload(add(p, 0x20))
            }
        }
    }

    /// @dev Initiates memory allocation for packed logs with `n` log items.
    function _packedLogsMalloc(uint256 n) private pure returns (bytes32 p) {
        /// @solidity memory-safe-assembly
        assembly {
            // `p`'s layout:
            //     uint256 offset;
            //     uint256 addressAndBit;
            //     uint256[] logs;
            p := mload(0x40)
            let logs := add(p, 0xa0)
            mstore(logs, n) // Store the length.
            let offset := add(0x20, logs) // Skip the word for `p.logs.length`.
            mstore(0x40, add(offset, shl(5, n))) // Allocate memory.
            mstore(add(0x40, p), logs) // Set `p.logs`.
            mstore(p, offset) // Set `p.offset`.
        }
    }

    /// @dev Set the current address and the burn bit.
    function _packedLogsSet(
        bytes32 p,
        address a,
        uint256 burnBit
    ) private pure {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(add(p, 0x20), or(shl(96, a), burnBit)) // Set `p.addressAndBit`.
        }
    }

    /// @dev Adds a packed log item to `p` with token `id`.
    function _packedLogsAppend(bytes32 p, uint256 id) private pure {
        /// @solidity memory-safe-assembly
        assembly {
            let offset := mload(p)
            mstore(offset, or(mload(add(p, 0x20)), shl(8, id))) // `p.addressAndBit | (id << 8)`.
            mstore(p, add(offset, 0x20))
        }
    }

    /// @dev Calls the `mirror` NFT contract to emit {Transfer} events for packed logs `p`.
    function _packedLogsSend(bytes32 p, DN404Storage storage $) private {
        address mirror = $.mirrorERC721;
        /// @solidity memory-safe-assembly
        assembly {
            let logs := mload(add(p, 0x40))
            let o := sub(logs, 0x40) // Start of calldata to send.
            mstore(o, 0x263c69d6) // `logTransfer(uint256[])`.
            mstore(add(o, 0x20), 0x20) // Offset of `logs` in the calldata to send.
            let n := add(0x44, shl(5, mload(logs))) // Length of calldata to send.
            if iszero(
                and(
                    eq(mload(o), 1),
                    call(gas(), mirror, 0, add(o, 0x1c), n, o, 0x20)
                )
            ) {
                revert(o, 0x00)
            }
        }
    }

    /// @dev Returns the token IDs of the packed logs (destructively).
    function _packedLogsIds(
        bytes32 p
    ) private pure returns (uint256[] memory ids) {
        /// @solidity memory-safe-assembly
        assembly {
            if p {
                ids := mload(add(p, 0x40))
                let o := add(ids, 0x20)
                let end := add(o, shl(5, mload(ids)))
                for {

                } iszero(eq(o, end)) {
                    o := add(o, 0x20)
                } {
                    mstore(o, shr(168, shl(160, mload(o))))
                }
            }
        }
    }

    /// @dev Returns an array of zero addresses.
    function _zeroAddresses(
        uint256 n
    ) private pure returns (address[] memory result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := mload(0x40)
            mstore(0x40, add(add(result, 0x20), shl(5, n)))
            mstore(result, n)
            codecopy(add(result, 0x20), codesize(), shl(5, n))
        }
    }

    /// @dev Returns an array each set to `value`.
    function _filled(
        uint256 n,
        uint256 value
    ) private pure returns (uint256[] memory result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := mload(0x40)
            let o := add(result, 0x20)
            let end := add(o, shl(5, n))
            mstore(0x40, end)
            mstore(result, n)
            for {

            } iszero(eq(o, end)) {
                o := add(o, 0x20)
            } {
                mstore(o, value)
            }
        }
    }

    /// @dev Returns an array each set to `value`.
    function _filled(
        uint256 n,
        address value
    ) private pure returns (address[] memory result) {
        result = _toAddresses(_filled(n, uint160(value)));
    }

    /// @dev Concatenates the arrays.
    function _concat(
        uint256[] memory a,
        uint256[] memory b
    ) private view returns (uint256[] memory result) {
        uint256 aN = a.length;
        uint256 bN = b.length;
        if (aN == uint256(0)) return b;
        if (bN == uint256(0)) return a;
        /// @solidity memory-safe-assembly
        assembly {
            let n := add(aN, bN)
            if n {
                result := mload(0x40)
                mstore(result, n)
                let o := add(result, 0x20)
                mstore(0x40, add(o, shl(5, n)))
                let aL := shl(5, aN)
                pop(staticcall(gas(), 4, add(a, 0x20), aL, o, aL))
                pop(
                    staticcall(
                        gas(),
                        4,
                        add(b, 0x20),
                        shl(5, bN),
                        add(o, aL),
                        shl(5, bN)
                    )
                )
            }
        }
    }

    /// @dev Concatenates the arrays.
    function _concat(
        address[] memory a,
        address[] memory b
    ) private view returns (address[] memory result) {
        result = _toAddresses(_concat(_toUints(a), _toUints(b)));
    }

    /// @dev Reinterpret cast to an uint array.
    function _toUints(
        address[] memory a
    ) private pure returns (uint256[] memory casted) {
        /// @solidity memory-safe-assembly
        assembly {
            casted := a
        }
    }

    /// @dev Reinterpret cast to an address array.
    function _toAddresses(
        uint256[] memory a
    ) private pure returns (address[] memory casted) {
        /// @solidity memory-safe-assembly
        assembly {
            casted := a
        }
    }

    /// @dev Struct of temporary variables for transfers.
    struct _DNTransferTemps {
        uint256 numNFTBurns;
        uint256 numNFTMints;
        uint256 fromOwnedLength;
        uint256 toOwnedLength;
        uint256 totalNFTSupply;
        uint256 fromEnd;
        uint256 toEnd;
        uint32 toAlias;
        uint256 nextTokenId;
        uint32 burnedPoolTail;
        bytes32 directLogs;
        bytes32 packedLogs;
    }

    /// @dev Struct of temporary variables for mints.
    struct _DNMintTemps {
        uint256 nextTokenId;
        uint32 burnedPoolTail;
        uint256 toEnd;
        uint32 toAlias;
        uint256 numNFTMints;
        bytes32 packedLogs;
    }

    /// @dev Struct of temporary variables for burns.
    struct _DNBurnTemps {
        uint256 fromBalance;
        uint256 totalSupply;
        uint256 numNFTBurns;
        bytes32 packedLogs;
    }

    /// @dev Returns the calldata value at `offset`.
    function _calldataload(
        uint256 offset
    ) private pure returns (uint256 value) {
        /// @solidity memory-safe-assembly
        assembly {
            value := calldataload(offset)
        }
    }

    /// @dev Executes a return opcode to return `x` and end the current call frame.
    function _return(uint256 x) private pure {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, x)
            return(0x00, 0x20)
        }
    }
}

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

/// @title DN404Mirror
/// @notice DN404Mirror provides an interface for interacting with the
/// NFT tokens in a DN404 implementation.
///
/// @author vectorized.eth (@optimizoor)
/// @author Quit (@0xQuit)
/// @author Michael Amadi (@AmadiMichaels)
/// @author cygaar (@0xCygaar)
/// @author Thomas (@0xjustadev)
/// @author Harrison (@PopPunkOnChain)
///
/// @dev Note:
/// - The ERC721 data is stored in the base DN404 contract.
contract DN404Mirror {
    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                           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 The ownership is transferred from `oldOwner` to `newOwner`.
    /// This is for marketplace signaling purposes. This contract has a `pullOwner()`
    /// function that will sync the owner from the base contract.
    event OwnershipTransferred(
        address indexed oldOwner,
        address indexed newOwner
    );

    /// @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;

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                        CUSTOM ERRORS                       */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Thrown when a call for an NFT function did not originate
    /// from the base DN404 contract.
    error SenderNotBase();

    /// @dev Thrown when a call for an NFT function did not originate from the deployer.
    error SenderNotDeployer();

    /// @dev Thrown when transferring an NFT to a contract address that
    /// does not implement ERC721Receiver.
    error TransferToNonERC721ReceiverImplementer();

    /// @dev Thrown when a linkMirrorContract call is received and the
    /// NFT mirror contract has already been linked to a DN404 base contract.
    error AlreadyLinked();

    /// @dev Thrown when retrieving the base DN404 address when a link has not
    /// been established.
    error NotLinked();

    /// @dev The function selector is not recognized.
    error FnSelectorNotRecognized();

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                          STORAGE                           */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Struct contain the NFT mirror contract storage.
    struct DN404NFTStorage {
        // Address of the ERC20 base contract.
        address baseERC20;
        // The deployer, if provided. If non-zero, the initialization of the
        // ERC20 <-> ERC721 link can only be done by the deployer via the ERC20 base contract.
        address deployer;
        // The owner of the ERC20 base contract. For marketplace signaling.
        address owner;
    }

    /// @dev Returns a storage pointer for DN404NFTStorage.
    function _getDN404NFTStorage()
        internal
        pure
        virtual
        returns (DN404NFTStorage storage $)
    {
        /// @solidity memory-safe-assembly
        assembly {
            // `uint72(bytes9(keccak256("DN404_MIRROR_STORAGE")))`.
            $.slot := 0x3602298b8c10b01230 // Truncate to 9 bytes to reduce bytecode size.
        }
    }

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                        CONSTRUCTOR                         */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    constructor(address deployer) {
        // For non-proxies, we will store the deployer so that only the deployer can
        // link the base contract.
        _getDN404NFTStorage().deployer = deployer;
    }

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                     ERC721 OPERATIONS                      */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Returns the token collection name from the base DN404 contract.
    function name() public view virtual returns (string memory) {
        return _readString(0x06fdde03, 0); // `name()`.
    }

    /// @dev Returns the token collection symbol from the base DN404 contract.
    function symbol() public view virtual returns (string memory) {
        return _readString(0x95d89b41, 0); // `symbol()`.
    }

    /// @dev Returns the Uniform Resource Identifier (URI) for token `id` from
    /// the base DN404 contract.
    function tokenURI(uint256 id) public view virtual returns (string memory) {
        ownerOf(id); // `ownerOf` reverts if the token does not exist.
        // We'll leave if optional for `_tokenURI` to revert for non-existent token
        // on the ERC20 side, since this is only recommended by the ERC721 standard.
        return _readString(0xcb30b460, id); // `tokenURINFT(uint256)`.
    }

    /// @dev Returns the total NFT supply from the base DN404 contract.
    function totalSupply() public view virtual returns (uint256) {
        return _readWord(0xe2c79281, 0, 0); // `totalNFTSupply()`.
    }

    /// @dev Returns the number of NFT tokens owned by `nftOwner` from the base DN404 contract.
    ///
    /// Requirements:
    /// - `nftOwner` must not be the zero address.
    function balanceOf(address nftOwner) public view virtual returns (uint256) {
        return _readWord(0xf5b100ea, uint160(nftOwner), 0); // `balanceOfNFT(address)`.
    }

    /// @dev Returns the owner of token `id` from the base DN404 contract.
    ///
    /// Requirements:
    /// - Token `id` must exist.
    function ownerOf(uint256 id) public view virtual returns (address) {
        return address(uint160(_readWord(0x2d8a746e, id, 0))); // `ownerOfNFT(uint256)`.
    }

    /// @dev Returns the owner of token `id` from the base DN404 contract.
    /// Returns `address(0)` instead of reverting if the token does not exist.
    function ownerAt(uint256 id) public view virtual returns (address) {
        return address(uint160(_readWord(0xc016aa52, id, 0))); // `ownerAtNFT(uint256)`.
    }

    /// @dev Sets `spender` as the approved account to manage token `id` in
    /// the base DN404 contract.
    ///
    /// 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 spender, uint256 id) public payable virtual {
        address base = baseERC20();
        /// @solidity memory-safe-assembly
        assembly {
            spender := shr(96, shl(96, spender))
            let m := mload(0x40)
            mstore(0x00, 0xd10b6e0c) // `approveNFT(address,uint256,address)`.
            mstore(0x20, spender)
            mstore(0x40, id)
            mstore(0x60, caller())
            if iszero(
                and(
                    // Arguments of `and` are evaluated last to first.
                    gt(returndatasize(), 0x1f), // The call must return at least 32 bytes.
                    call(gas(), base, callvalue(), 0x1c, 0x64, 0x00, 0x20)
                )
            ) {
                returndatacopy(m, 0x00, returndatasize())
                revert(m, returndatasize())
            }
            mstore(0x40, m) // Restore the free memory pointer.
            mstore(0x60, 0) // Restore the zero pointer.
            // Emit the {Approval} event.
            log4(
                codesize(),
                0x00,
                _APPROVAL_EVENT_SIGNATURE,
                shr(96, mload(0x0c)),
                spender,
                id
            )
        }
    }

    /// @dev Returns the account approved to manage token `id` from
    /// the base DN404 contract.
    ///
    /// Requirements:
    /// - Token `id` must exist.
    function getApproved(uint256 id) public view virtual returns (address) {
        return address(uint160(_readWord(0x27ef5495, id, 0))); // `getApprovedNFT(uint256)`.
    }

    /// @dev Sets whether `operator` is approved to manage the tokens of the caller in
    /// the base DN404 contract.
    ///
    /// Emits an {ApprovalForAll} event.
    function setApprovalForAll(address operator, bool approved) public virtual {
        address base = baseERC20();
        /// @solidity memory-safe-assembly
        assembly {
            operator := shr(96, shl(96, operator))
            let m := mload(0x40)
            mstore(0x00, 0xf6916ddd) // `setApprovalForAllNFT(address,bool,address)`.
            mstore(0x20, operator)
            mstore(0x40, iszero(iszero(approved)))
            mstore(0x60, caller())
            if iszero(
                and(
                    // Arguments of `and` are evaluated last to first.
                    eq(mload(0x00), 1), // The call must return 1.
                    call(gas(), base, callvalue(), 0x1c, 0x64, 0x00, 0x20)
                )
            ) {
                returndatacopy(m, 0x00, returndatasize())
                revert(m, returndatasize())
            }
            // Emit the {ApprovalForAll} event.
            // The `approved` value is already at 0x40.
            log3(
                0x40,
                0x20,
                _APPROVAL_FOR_ALL_EVENT_SIGNATURE,
                caller(),
                operator
            )
            mstore(0x40, m) // Restore the free memory pointer.
            mstore(0x60, 0) // Restore the zero pointer.
        }
    }

    /// @dev Returns whether `operator` is approved to manage the tokens of `nftOwner` from
    /// the base DN404 contract.
    function isApprovedForAll(
        address nftOwner,
        address operator
    ) public view virtual returns (bool) {
        // `isApprovedForAllNFT(address,address)`.
        return _readWord(0x62fb246d, uint160(nftOwner), uint160(operator)) != 0;
    }

    /// @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 {
        address base = baseERC20();
        /// @solidity memory-safe-assembly
        assembly {
            from := shr(96, shl(96, from))
            to := shr(96, shl(96, to))
            let m := mload(0x40)
            mstore(m, 0xe5eb36c8) // `transferFromNFT(address,address,uint256,address)`.
            mstore(add(m, 0x20), from)
            mstore(add(m, 0x40), to)
            mstore(add(m, 0x60), id)
            mstore(add(m, 0x80), caller())
            if iszero(
                and(
                    // Arguments of `and` are evaluated last to first.
                    eq(mload(m), 1), // The call must return 1.
                    call(gas(), base, callvalue(), add(m, 0x1c), 0x84, m, 0x20)
                )
            ) {
                returndatacopy(m, 0x00, returndatasize())
                revert(m, returndatasize())
            }
            // Emit the {Transfer} event.
            log4(codesize(), 0x00, _TRANSFER_EVENT_SIGNATURE, 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)
            )
        }
    }

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                  OWNER SYNCING OPERATIONS                  */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Returns the `owner` of the contract, for marketplace signaling purposes.
    function owner() public view virtual returns (address) {
        return _getDN404NFTStorage().owner;
    }

    /// @dev Permissionless function to pull the owner from the base DN404 contract
    /// if it implements ownable, for marketplace signaling purposes.
    function pullOwner() public virtual returns (bool) {
        address newOwner;
        address base = baseERC20();
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, 0x8da5cb5b) // `owner()`.
            let success := staticcall(gas(), base, 0x1c, 0x04, 0x00, 0x20)
            newOwner := mul(
                shr(96, mload(0x0c)),
                and(gt(returndatasize(), 0x1f), success)
            )
        }
        DN404NFTStorage storage $ = _getDN404NFTStorage();
        address oldOwner = $.owner;
        if (oldOwner != newOwner) {
            $.owner = newOwner;
            emit OwnershipTransferred(oldOwner, newOwner);
        }
        return true;
    }

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                     MIRROR OPERATIONS                      */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Returns the address of the base DN404 contract.
    function baseERC20() public view virtual returns (address base) {
        base = _getDN404NFTStorage().baseERC20;
        if (base == address(0)) revert NotLinked();
    }

    /// @dev Fallback modifier to execute calls from the base DN404 contract.
    modifier dn404NFTFallback() virtual {
        DN404NFTStorage storage $ = _getDN404NFTStorage();

        uint256 fnSelector = _calldataload(0x00) >> 224;

        // `logTransfer(uint256[])`.
        if (fnSelector == 0x263c69d6) {
            if (msg.sender != $.baseERC20) revert SenderNotBase();
            /// @solidity memory-safe-assembly
            assembly {
                let o := add(0x24, calldataload(0x04)) // Packed logs offset.
                let end := add(o, shl(5, calldataload(sub(o, 0x20))))
                for {

                } iszero(eq(o, end)) {
                    o := add(0x20, o)
                } {
                    let d := calldataload(o) // Entry in the packed logs.
                    let a := shr(96, d) // The address.
                    let b := and(1, d) // Whether it is a burn.
                    log4(
                        codesize(),
                        0x00,
                        _TRANSFER_EVENT_SIGNATURE,
                        mul(a, b), // `from`.
                        mul(a, iszero(b)), // `to`.
                        shr(168, shl(160, d)) // `id`.
                    )
                }
                mstore(0x00, 0x01)
                return(0x00, 0x20)
            }
        }
        // `logDirectTransfer(address,address,uint256[])`.
        if (fnSelector == 0x144027d3) {
            if (msg.sender != $.baseERC20) revert SenderNotBase();
            /// @solidity memory-safe-assembly
            assembly {
                let from := calldataload(0x04)
                let to := calldataload(0x24)
                let o := add(0x24, calldataload(0x44)) // Direct logs offset.
                let end := add(o, shl(5, calldataload(sub(o, 0x20))))
                for {

                } iszero(eq(o, end)) {
                    o := add(0x20, o)
                } {
                    log4(
                        codesize(),
                        0x00,
                        _TRANSFER_EVENT_SIGNATURE,
                        from,
                        to,
                        calldataload(o)
                    )
                }
                mstore(0x00, 0x01)
                return(0x00, 0x20)
            }
        }
        // `linkMirrorContract(address)`.
        if (fnSelector == 0x0f4599e5) {
            if ($.deployer != address(0)) {
                if (address(uint160(_calldataload(0x04))) != $.deployer) {
                    revert SenderNotDeployer();
                }
            }
            if ($.baseERC20 != address(0)) revert AlreadyLinked();
            $.baseERC20 = msg.sender;
            /// @solidity memory-safe-assembly
            assembly {
                mstore(0x00, 0x01)
                return(0x00, 0x20)
            }
        }
        _;
    }

    /// @dev Fallback function for calls from base DN404 contract.
    /// Override this if you need to implement your custom
    /// fallback with utilities like Solady's `LibZip.cdFallback()`.
    /// And always remember to always wrap the fallback with `dn404NFTFallback`.
    fallback() external payable virtual dn404NFTFallback {
        revert FnSelectorNotRecognized(); // Not mandatory. Just for quality of life.
    }

    /// @dev This is to silence the compiler warning.
    /// Override and remove the revert if you want your contract to receive ETH via receive.
    receive() external payable virtual {
        if (msg.value != 0) revert();
    }

    /*«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-«-*/
    /*                      PRIVATE HELPERS                       */
    /*-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»-»*/

    /// @dev Helper to read a string from the base DN404 contract.
    function _readString(
        uint256 fnSelector,
        uint256 arg0
    ) private view returns (string memory result) {
        address base = baseERC20();
        /// @solidity memory-safe-assembly
        assembly {
            result := mload(0x40)
            mstore(0x00, fnSelector)
            mstore(0x20, arg0)
            if iszero(staticcall(gas(), base, 0x1c, 0x24, 0x00, 0x00)) {
                returndatacopy(result, 0x00, returndatasize())
                revert(result, returndatasize())
            }
            returndatacopy(0x00, 0x00, 0x20) // Copy the offset of the string in returndata.
            returndatacopy(result, mload(0x00), 0x20) // Copy the length of the string.
            returndatacopy(
                add(result, 0x20),
                add(mload(0x00), 0x20),
                mload(result)
            ) // Copy the string.
            let end := add(add(result, 0x20), mload(result))
            mstore(end, 0) // Zeroize the word after the string.
            mstore(0x40, add(end, 0x20)) // Allocate memory.
        }
    }

    /// @dev Helper to read a word from the base DN404 contract.
    function _readWord(
        uint256 fnSelector,
        uint256 arg0,
        uint256 arg1
    ) private view returns (uint256 result) {
        address base = baseERC20();
        /// @solidity memory-safe-assembly
        assembly {
            let m := mload(0x40)
            mstore(0x00, fnSelector)
            mstore(0x20, arg0)
            mstore(0x40, arg1)
            if iszero(
                and(
                    // Arguments of `and` are evaluated last to first.
                    gt(returndatasize(), 0x1f), // The call must return at least 32 bytes.
                    staticcall(gas(), base, 0x1c, 0x44, 0x00, 0x20)
                )
            ) {
                returndatacopy(m, 0x00, returndatasize())
                revert(m, returndatasize())
            }
            mstore(0x40, m) // Restore the free memory pointer.
            result := mload(0x00)
        }
    }

    /// @dev Returns the calldata value at `offset`.
    function _calldataload(
        uint256 offset
    ) private pure returns (uint256 value) {
        /// @solidity memory-safe-assembly
        assembly {
            value := calldataload(offset)
        }
    }

    /// @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)
            }
        }
    }
}

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

import "./DN404.sol";
import "./FameMirror.sol";
import {ITokenURIGenerator} from "./ITokenURIGenerator.sol";
import {LibString} from "solady/utils/LibString.sol";
import {SafeTransferLib} from "solady/utils/SafeTransferLib.sol";
import {OwnableRoles} from "solady/auth/OwnableRoles.sol";
import {IBurnedPoolManager} from "./IBurnedPoolManager.sol";
import {ClaimToFame} from "./ClaimToFame.sol";

interface IBalanceOf {
    function balanceOf(address account) external view returns (uint256);
}

/**
 * @title SimpleDN404
 * @notice Sample DN404 contract that demonstrates the owner selling fungible tokens.
 * When a user has at least one base unit (10^18) amount of tokens, they will automatically receive an NFT.
 * NFTs are minted as an address accumulates each base unit amount of tokens.
 */
contract Fame is DN404, OwnableRoles {
    using LibString for uint256;
    string private _name;
    string private _symbol;

    uint256 internal constant RENDERER = _ROLE_0;
    uint256 internal constant METADATA = _ROLE_1;
    uint256 internal constant BURN_POOL_MANAGER = _ROLE_2;
    uint256 internal constant SKIP_MANAGER = _ROLE_3;
    uint256 internal constant LAUNCHER = _ROLE_4;

    // The proxy owner role for managing roles
    uint256 internal constant ADMIN = _ROLE_255;

    IBalanceOf private claimToFame;
    bool private hasLaunched = false;
    IBurnedPoolManager public burnedPoolManager;
    ITokenURIGenerator public renderer;

    constructor(
        string memory name_,
        string memory symbol_,
        address claimToFameAddress
    ) {
        _initializeOwner(msg.sender);

        _name = name_;
        _symbol = symbol_;

        address mirror = address(new FameMirror(msg.sender));
        _initializeDN404(888 * _unit(), msg.sender, mirror);
        _grantRoles(msg.sender, ADMIN);
        claimToFame = IBalanceOf(claimToFameAddress);
    }

    function name() public view override returns (string memory) {
        return _name;
    }

    function symbol() public view override returns (string memory) {
        return _symbol;
    }

    /// @dev Amount of token balance that is equal to one NFT.
    function _unit() internal view virtual override returns (uint256) {
        return 1_000_000 * 10 ** 18;
    }

    /// @dev Amount of token balance that is equal to one NFT.
    function unit() public view returns (uint256) {
        return _unit();
    }

    function withdraw() public onlyOwner {
        SafeTransferLib.safeTransferAllETH(msg.sender);
    }

    function transfer(
        address to,
        uint256 value
    ) public override onlyLaunched returns (bool) {
        return super.transfer(to, value);
    }

    error NoTransferWhenStaked();
    /**
     *
     */
    function _addToBurnedPool(
        uint256 totalNFTSupplyAfterBurn,
        uint256 totalSupplyAfterBurn
    ) internal view override returns (bool) {
        if (address(burnedPoolManager) != address(0)) {
            return
                burnedPoolManager.addToBurnedPool(
                    totalNFTSupplyAfterBurn,
                    totalSupplyAfterBurn
                );
        }
        return true;
    }

    function setBurnedPoolManager(
        address newBurnedPoolManager
    ) public onlyRoles(BURN_POOL_MANAGER) {
        burnedPoolManager = IBurnedPoolManager(newBurnedPoolManager);
    }

    function setSkipNftForAccount(
        address account,
        bool skip
    ) public onlyRoles(SKIP_MANAGER) {
        _setSkipNFT(account, skip);
    }

    error AlreadyLaunched();
    function launchPublic() public payable onlyOwner {
        if (hasLaunched) {
            revert AlreadyLaunched();
        }
        hasLaunched = true;
    }
    error NotLaunched();
    modifier onlyLaunched() {
        if (
            !hasLaunched &&
            !hasAnyRole(tx.origin, LAUNCHER) &&
            claimToFame.balanceOf(tx.origin) == 0
        ) {
            revert NotLaunched();
        }
        _;
    }

    /**
     * @dev Returns the URI for a given token ID
     *
     * @param tokenId the tokens ID to retrieve metadata for
     */
    function _tokenURI(
        uint256 tokenId
    ) internal view override returns (string memory result) {
        result = renderer.tokenURI(tokenId);
    }

    /**
     * @dev Updates the renderer to a new render contract. Can only be called by an address with the UPDATE_RENDERER_ROLE. Emits an EIP4906 BatchMetadataUpdate event
     *
     * @param newRenderer the new renderer
     */
    function setRenderer(address newRenderer) public onlyRoles(METADATA) {
        _removeRoles(address(renderer), RENDERER);
        renderer = ITokenURIGenerator(newRenderer);
        if (address(renderer) != address(0))
            _grantRoles(address(renderer), RENDERER);
    }

    function emitMetadataUpdate(uint256 tokenId) external onlyRoles(RENDERER) {
        fameMirror().emitMetadataUpdate(tokenId);
    }

    function emitBatchMetadataUpdate(
        uint256 fromTokenId,
        uint256 toTokenId
    ) external onlyRoles(RENDERER) {
        fameMirror().emitBatchMetadataUpdate(fromTokenId, toTokenId);
    }

    function fameMirror() public view returns (FameMirror) {
        return FameMirror(payable(_getDN404Storage().mirrorERC721));
    }

    /// @dev Allows the ADMIN to grant `user` `roles`.
    /// If the `user` already has a role, then it will be an no-op for the role.
    function grantRoles(
        address user,
        uint256 roles
    ) public payable override onlyRoles(ADMIN) {
        _grantRoles(user, roles);
    }

    /// @dev Allows the ADMIN to remove `user` `roles`.
    /// If the `user` does not have a role, then it will be an no-op for the role.
    function revokeRoles(
        address user,
        uint256 roles
    ) public payable override onlyRoles(ADMIN) {
        _removeRoles(user, roles);
    }
}

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

import "./DN404Mirror.sol";
import {ITokenURIGenerator} from "./ITokenURIGenerator.sol";
import {IERC4906} from "./IERC4906.sol";

/**
 * @title FameMirror
 * @notice DN404 Mirror (NFT) contract that mirrors the fungible token contract.
 * This contract is used to mint NFTs for users who have accumulated a certain amount of fungible tokens.
 * Also Implements the EIP-5805 standard (ERC721Votes) and EIP-6372 standard (clock)
 */
contract FameMirror is DN404Mirror, IERC4906 {
    constructor(address _owner) DN404Mirror(_owner) {}

    error OnlyERC20CanCall();

    modifier onlyERC20() {
        if (msg.sender != address(_getDN404NFTStorage().baseERC20)) {
            revert OnlyERC20CanCall();
        }
        _;
    }

    function emitMetadataUpdate(uint256 tokenId) external onlyERC20 {
        emit MetadataUpdate(tokenId);
    }

    function emitBatchMetadataUpdate(
        uint256 fromTokenId,
        uint256 toTokenId
    ) external onlyERC20 {
        emit BatchMetadataUpdate(fromTokenId, toTokenId);
    }
}

pragma solidity ^0.8.4;

interface IBurnedPoolManager {
    function addToBurnedPool(
        uint256 totalNFTSupplyAfterBurn,
        uint256 totalSupplyAfterBurn
    ) external pure returns (bool);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.20;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);

    /**
     * @dev Returns the value of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the value of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves a `value` amount of tokens from the caller's account to `to`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address to, uint256 value) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets a `value` amount of tokens as the allowance of `spender` over the
     * caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 value) external returns (bool);

    /**
     * @dev Moves a `value` amount of tokens from `from` to `to` using the
     * allowance mechanism. `value` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address from, address to, uint256 value) external returns (bool);
}

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

interface IERC4906 {
    /// @dev This event emits when the metadata of a token is changed.
    /// So that the third-party platforms such as NFT market could
    /// timely update the images and related attributes of the NFT.
    event MetadataUpdate(uint256 _tokenId);

    /// @dev This event emits when the metadata of a range of tokens is changed.
    /// So that the third-party platforms such as NFT market could
    /// timely update the images and related attributes of the NFTs.    
    event BatchMetadataUpdate(uint256 _fromTokenId, uint256 _toTokenId);
}

// SPDX-License-Identifier: UNLICENSED
pragma solidity >=0.8.9 <0.9.0;

interface ITokenURIGenerator {
  function tokenURI(uint256 tokenId) external view returns (string memory);
}

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

/// @notice Library for bit twiddling and boolean operations.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/utils/LibBit.sol)
/// @author Inspired by (https://graphics.stanford.edu/~seander/bithacks.html)
library LibBit {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                  BIT TWIDDLING OPERATIONS                  */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Find last set.
    /// Returns the index of the most significant bit of `x`,
    /// counting from the least significant bit position.
    /// If `x` is zero, returns 256.
    function fls(uint256 x) internal pure returns (uint256 r) {
        /// @solidity memory-safe-assembly
        assembly {
            r := or(shl(8, iszero(x)), shl(7, lt(0xffffffffffffffffffffffffffffffff, x)))
            r := or(r, shl(6, lt(0xffffffffffffffff, shr(r, x))))
            r := or(r, shl(5, lt(0xffffffff, shr(r, x))))
            r := or(r, shl(4, lt(0xffff, shr(r, x))))
            r := or(r, shl(3, lt(0xff, shr(r, x))))
            // forgefmt: disable-next-item
            r := or(r, byte(and(0x1f, shr(shr(r, x), 0x8421084210842108cc6318c6db6d54be)),
                0x0706060506020504060203020504030106050205030304010505030400000000))
        }
    }

    /// @dev Count leading zeros.
    /// Returns the number of zeros preceding the most significant one bit.
    /// If `x` is zero, returns 256.
    function clz(uint256 x) internal pure returns (uint256 r) {
        /// @solidity memory-safe-assembly
        assembly {
            r := shl(7, lt(0xffffffffffffffffffffffffffffffff, x))
            r := or(r, shl(6, lt(0xffffffffffffffff, shr(r, x))))
            r := or(r, shl(5, lt(0xffffffff, shr(r, x))))
            r := or(r, shl(4, lt(0xffff, shr(r, x))))
            r := or(r, shl(3, lt(0xff, shr(r, x))))
            // forgefmt: disable-next-item
            r := add(xor(r, byte(and(0x1f, shr(shr(r, x), 0x8421084210842108cc6318c6db6d54be)),
                0xf8f9f9faf9fdfafbf9fdfcfdfafbfcfef9fafdfafcfcfbfefafafcfbffffffff)), iszero(x))
        }
    }

    /// @dev Find first set.
    /// Returns the index of the least significant bit of `x`,
    /// counting from the least significant bit position.
    /// If `x` is zero, returns 256.
    /// Equivalent to `ctz` (count trailing zeros), which gives
    /// the number of zeros following the least significant one bit.
    function ffs(uint256 x) internal pure returns (uint256 r) {
        /// @solidity memory-safe-assembly
        assembly {
            // Isolate the least significant bit.
            x := and(x, add(not(x), 1))
            // For the upper 3 bits of the result, use a De Bruijn-like lookup.
            // Credit to adhusson: https://blog.adhusson.com/cheap-find-first-set-evm/
            // forgefmt: disable-next-item
            r := shl(5, shr(252, shl(shl(2, shr(250, mul(x,
                0xb6db6db6ddddddddd34d34d349249249210842108c6318c639ce739cffffffff))),
                0x8040405543005266443200005020610674053026020000107506200176117077)))
            // For the lower 5 bits of the result, use a De Bruijn lookup.
            // forgefmt: disable-next-item
            r := or(r, byte(and(div(0xd76453e0, shr(r, x)), 0x1f),
                0x001f0d1e100c1d070f090b19131c1706010e11080a1a141802121b1503160405))
        }
    }

    /// @dev Returns the number of set bits in `x`.
    function popCount(uint256 x) internal pure returns (uint256 c) {
        /// @solidity memory-safe-assembly
        assembly {
            let max := not(0)
            let isMax := eq(x, max)
            x := sub(x, and(shr(1, x), div(max, 3)))
            x := add(and(x, div(max, 5)), and(shr(2, x), div(max, 5)))
            x := and(add(x, shr(4, x)), div(max, 17))
            c := or(shl(8, isMax), shr(248, mul(x, div(max, 255))))
        }
    }

    /// @dev Returns whether `x` is a power of 2.
    function isPo2(uint256 x) internal pure returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            // Equivalent to `x && !(x & (x - 1))`.
            result := iszero(add(and(x, sub(x, 1)), iszero(x)))
        }
    }

    /// @dev Returns `x` reversed at the bit level.
    function reverseBits(uint256 x) internal pure returns (uint256 r) {
        uint256 m0 = 0x0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f;
        uint256 m1 = m0 ^ (m0 << 2);
        uint256 m2 = m1 ^ (m1 << 1);
        r = reverseBytes(x);
        r = (m2 & (r >> 1)) | ((m2 & r) << 1);
        r = (m1 & (r >> 2)) | ((m1 & r) << 2);
        r = (m0 & (r >> 4)) | ((m0 & r) << 4);
    }

    /// @dev Returns `x` reversed at the byte level.
    function reverseBytes(uint256 x) internal pure returns (uint256 r) {
        unchecked {
            // Computing masks on-the-fly reduces bytecode size by about 200 bytes.
            uint256 m0 = 0x100000000000000000000000000000001 * (~toUint(x == 0) >> 192);
            uint256 m1 = m0 ^ (m0 << 32);
            uint256 m2 = m1 ^ (m1 << 16);
            uint256 m3 = m2 ^ (m2 << 8);
            r = (m3 & (x >> 8)) | ((m3 & x) << 8);
            r = (m2 & (r >> 16)) | ((m2 & r) << 16);
            r = (m1 & (r >> 32)) | ((m1 & r) << 32);
            r = (m0 & (r >> 64)) | ((m0 & r) << 64);
            r = (r >> 128) | (r << 128);
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                     BOOLEAN OPERATIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    // A Solidity bool on the stack or memory is represented as a 256-bit word.
    // Non-zero values are true, zero is false.
    // A clean bool is either 0 (false) or 1 (true) under the hood.
    // Usually, if not always, the bool result of a regular Solidity expression,
    // or the argument of a public/external function will be a clean bool.
    // You can usually use the raw variants for more performance.
    // If uncertain, test (best with exact compiler settings).
    // Or use the non-raw variants (compiler can sometimes optimize out the double `iszero`s).

    /// @dev Returns `x & y`. Inputs must be clean.
    function rawAnd(bool x, bool y) internal pure returns (bool z) {
        /// @solidity memory-safe-assembly
        assembly {
            z := and(x, y)
        }
    }

    /// @dev Returns `x & y`.
    function and(bool x, bool y) internal pure returns (bool z) {
        /// @solidity memory-safe-assembly
        assembly {
            z := and(iszero(iszero(x)), iszero(iszero(y)))
        }
    }

    /// @dev Returns `x | y`. Inputs must be clean.
    function rawOr(bool x, bool y) internal pure returns (bool z) {
        /// @solidity memory-safe-assembly
        assembly {
            z := or(x, y)
        }
    }

    /// @dev Returns `x | y`.
    function or(bool x, bool y) internal pure returns (bool z) {
        /// @solidity memory-safe-assembly
        assembly {
            z := or(iszero(iszero(x)), iszero(iszero(y)))
        }
    }

    /// @dev Returns 1 if `b` is true, else 0. Input must be clean.
    function rawToUint(bool b) internal pure returns (uint256 z) {
        /// @solidity memory-safe-assembly
        assembly {
            z := b
        }
    }

    /// @dev Returns 1 if `b` is true, else 0.
    function toUint(bool b) internal pure returns (uint256 z) {
        /// @solidity memory-safe-assembly
        assembly {
            z := iszero(iszero(b))
        }
    }
}

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

import {LibBit} from "./LibBit.sol";

/// @notice Library for storage of packed unsigned booleans.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/utils/LibBitmap.sol)
/// @author Modified from Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/LibBitmap.sol)
/// @author Modified from Solidity-Bits (https://github.com/estarriolvetch/solidity-bits/blob/main/contracts/BitMaps.sol)
library LibBitmap {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                         CONSTANTS                          */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The constant returned when a bitmap scan does not find a result.
    uint256 internal constant NOT_FOUND = type(uint256).max;

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

    /// @dev A bitmap in storage.
    struct Bitmap {
        mapping(uint256 => uint256) map;
    }

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

    /// @dev Returns the boolean value of the bit at `index` in `bitmap`.
    function get(Bitmap storage bitmap, uint256 index) internal view returns (bool isSet) {
        // It is better to set `isSet` to either 0 or 1, than zero vs non-zero.
        // Both cost the same amount of gas, but the former allows the returned value
        // to be reused without cleaning the upper bits.
        uint256 b = (bitmap.map[index >> 8] >> (index & 0xff)) & 1;
        /// @solidity memory-safe-assembly
        assembly {
            isSet := b
        }
    }

    /// @dev Updates the bit at `index` in `bitmap` to true.
    function set(Bitmap storage bitmap, uint256 index) internal {
        bitmap.map[index >> 8] |= (1 << (index & 0xff));
    }

    /// @dev Updates the bit at `index` in `bitmap` to false.
    function unset(Bitmap storage bitmap, uint256 index) internal {
        bitmap.map[index >> 8] &= ~(1 << (index & 0xff));
    }

    /// @dev Flips the bit at `index` in `bitmap`.
    /// Returns the boolean result of the flipped bit.
    function toggle(Bitmap storage bitmap, uint256 index) internal returns (bool newIsSet) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x20, bitmap.slot)
            mstore(0x00, shr(8, index))
            let storageSlot := keccak256(0x00, 0x40)
            let shift := and(index, 0xff)
            let storageValue := xor(sload(storageSlot), shl(shift, 1))
            // It makes sense to return the `newIsSet`,
            // as it allow us to skip an additional warm `sload`,
            // and it costs minimal gas (about 15),
            // which may be optimized away if the returned value is unused.
            newIsSet := and(1, shr(shift, storageValue))
            sstore(storageSlot, storageValue)
        }
    }

    /// @dev Updates the bit at `index` in `bitmap` to `shouldSet`.
    function setTo(Bitmap storage bitmap, uint256 index, bool shouldSet) internal {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x20, bitmap.slot)
            mstore(0x00, shr(8, index))
            let storageSlot := keccak256(0x00, 0x40)
            let storageValue := sload(storageSlot)
            let shift := and(index, 0xff)
            sstore(
                storageSlot,
                // Unsets the bit at `shift` via `and`, then sets its new value via `or`.
                or(and(storageValue, not(shl(shift, 1))), shl(shift, iszero(iszero(shouldSet))))
            )
        }
    }

    /// @dev Consecutively sets `amount` of bits starting from the bit at `start`.
    function setBatch(Bitmap storage bitmap, uint256 start, uint256 amount) internal {
        /// @solidity memory-safe-assembly
        assembly {
            let max := not(0)
            let shift := and(start, 0xff)
            mstore(0x20, bitmap.slot)
            mstore(0x00, shr(8, start))
            if iszero(lt(add(shift, amount), 257)) {
                let storageSlot := keccak256(0x00, 0x40)
                sstore(storageSlot, or(sload(storageSlot), shl(shift, max)))
                let bucket := add(mload(0x00), 1)
                let bucketEnd := add(mload(0x00), shr(8, add(amount, shift)))
                amount := and(add(amount, shift), 0xff)
                shift := 0
                for {} iszero(eq(bucket, bucketEnd)) { bucket := add(bucket, 1) } {
                    mstore(0x00, bucket)
                    sstore(keccak256(0x00, 0x40), max)
                }
                mstore(0x00, bucket)
            }
            let storageSlot := keccak256(0x00, 0x40)
            sstore(storageSlot, or(sload(storageSlot), shl(shift, shr(sub(256, amount), max))))
        }
    }

    /// @dev Consecutively unsets `amount` of bits starting from the bit at `start`.
    function unsetBatch(Bitmap storage bitmap, uint256 start, uint256 amount) internal {
        /// @solidity memory-safe-assembly
        assembly {
            let shift := and(start, 0xff)
            mstore(0x20, bitmap.slot)
            mstore(0x00, shr(8, start))
            if iszero(lt(add(shift, amount), 257)) {
                let storageSlot := keccak256(0x00, 0x40)
                sstore(storageSlot, and(sload(storageSlot), not(shl(shift, not(0)))))
                let bucket := add(mload(0x00), 1)
                let bucketEnd := add(mload(0x00), shr(8, add(amount, shift)))
                amount := and(add(amount, shift), 0xff)
                shift := 0
                for {} iszero(eq(bucket, bucketEnd)) { bucket := add(bucket, 1) } {
                    mstore(0x00, bucket)
                    sstore(keccak256(0x00, 0x40), 0)
                }
                mstore(0x00, bucket)
            }
            let storageSlot := keccak256(0x00, 0x40)
            sstore(
                storageSlot, and(sload(storageSlot), not(shl(shift, shr(sub(256, amount), not(0)))))
            )
        }
    }

    /// @dev Returns number of set bits within a range by
    /// scanning `amount` of bits starting from the bit at `start`.
    function popCount(Bitmap storage bitmap, uint256 start, uint256 amount)
        internal
        view
        returns (uint256 count)
    {
        unchecked {
            uint256 bucket = start >> 8;
            uint256 shift = start & 0xff;
            if (!(amount + shift < 257)) {
                count = LibBit.popCount(bitmap.map[bucket] >> shift);
                uint256 bucketEnd = bucket + ((amount + shift) >> 8);
                amount = (amount + shift) & 0xff;
                shift = 0;
                for (++bucket; bucket != bucketEnd; ++bucket) {
                    count += LibBit.popCount(bitmap.map[bucket]);
                }
            }
            count += LibBit.popCount((bitmap.map[bucket] >> shift) << (256 - amount));
        }
    }

    /// @dev Returns the index of the most significant set bit in `[0..upTo]`.
    /// If no set bit is found, returns `NOT_FOUND`.
    function findLastSet(Bitmap storage bitmap, uint256 upTo)
        internal
        view
        returns (uint256 setBitIndex)
    {
        uint256 bucket;
        uint256 bucketBits;
        /// @solidity memory-safe-assembly
        assembly {
            setBitIndex := not(0)
            bucket := shr(8, upTo)
            mstore(0x00, bucket)
            mstore(0x20, bitmap.slot)
            let offset := and(0xff, not(upTo)) // `256 - (255 & upTo) - 1`.
            bucketBits := shr(offset, shl(offset, sload(keccak256(0x00, 0x40))))
            if iszero(or(bucketBits, iszero(bucket))) {
                for {} 1 {} {
                    bucket := add(bucket, setBitIndex) // `sub(bucket, 1)`.
                    mstore(0x00, bucket)
                    bucketBits := sload(keccak256(0x00, 0x40))
                    if or(bucketBits, iszero(bucket)) { break }
                }
            }
        }
        if (bucketBits != 0) {
            setBitIndex = (bucket << 8) | LibBit.fls(bucketBits);
            /// @solidity memory-safe-assembly
            assembly {
                setBitIndex := or(setBitIndex, sub(0, gt(setBitIndex, upTo)))
            }
        }
    }
}

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

/// @notice Library for converting numbers into strings and other string operations.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/utils/LibString.sol)
/// @author Modified from Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/LibString.sol)
///
/// @dev Note:
/// For performance and bytecode compactness, most of the string operations are restricted to
/// byte strings (7-bit ASCII), except where otherwise specified.
/// Usage of byte string operations on charsets with runes spanning two or more bytes
/// can lead to undefined behavior.
library LibString {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                        CUSTOM ERRORS                       */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The length of the output is too small to contain all the hex digits.
    error HexLengthInsufficient();

    /// @dev The length of the string is more than 32 bytes.
    error TooBigForSmallString();

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

    /// @dev The constant returned when the `search` is not found in the string.
    uint256 internal constant NOT_FOUND = type(uint256).max;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                     DECIMAL OPERATIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the base 10 decimal representation of `value`.
    function toString(uint256 value) internal pure returns (string memory str) {
        /// @solidity memory-safe-assembly
        assembly {
            // The maximum value of a uint256 contains 78 digits (1 byte per digit), but
            // we allocate 0xa0 bytes to keep the free memory pointer 32-byte word aligned.
            // We will need 1 word for the trailing zeros padding, 1 word for the length,
            // and 3 words for a maximum of 78 digits.
            str := add(mload(0x40), 0x80)
            // Update the free memory pointer to allocate.
            mstore(0x40, add(str, 0x20))
            // Zeroize the slot after the string.
            mstore(str, 0)

            // Cache the end of the memory to calculate the length later.
            let end := str

            let w := not(0) // Tsk.
            // We write the string from rightmost digit to leftmost digit.
            // The following is essentially a do-while loop that also handles the zero case.
            for { let temp := value } 1 {} {
                str := add(str, w) // `sub(str, 1)`.
                // Write the character to the pointer.
                // The ASCII index of the '0' character is 48.
                mstore8(str, add(48, mod(temp, 10)))
                // Keep dividing `temp` until zero.
                temp := div(temp, 10)
                if iszero(temp) { break }
            }

            let length := sub(end, str)
            // Move the pointer 32 bytes leftwards to make room for the length.
            str := sub(str, 0x20)
            // Store the length.
            mstore(str, length)
        }
    }

    /// @dev Returns the base 10 decimal representation of `value`.
    function toString(int256 value) internal pure returns (string memory str) {
        if (value >= 0) {
            return toString(uint256(value));
        }
        unchecked {
            str = toString(~uint256(value) + 1);
        }
        /// @solidity memory-safe-assembly
        assembly {
            // We still have some spare memory space on the left,
            // as we have allocated 3 words (96 bytes) for up to 78 digits.
            let length := mload(str) // Load the string length.
            mstore(str, 0x2d) // Store the '-' character.
            str := sub(str, 1) // Move back the string pointer by a byte.
            mstore(str, add(length, 1)) // Update the string length.
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   HEXADECIMAL OPERATIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the hexadecimal representation of `value`,
    /// left-padded to an input length of `length` bytes.
    /// The output is prefixed with "0x" encoded using 2 hexadecimal digits per byte,
    /// giving a total length of `length * 2 + 2` bytes.
    /// Reverts if `length` is too small for the output to contain all the digits.
    function toHexString(uint256 value, uint256 length) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(value, length);
        /// @solidity memory-safe-assembly
        assembly {
            let strLength := add(mload(str), 2) // Compute the length.
            mstore(str, 0x3078) // Write the "0x" prefix.
            str := sub(str, 2) // Move the pointer.
            mstore(str, strLength) // Write the length.
        }
    }

    /// @dev Returns the hexadecimal representation of `value`,
    /// left-padded to an input length of `length` bytes.
    /// The output is prefixed with "0x" encoded using 2 hexadecimal digits per byte,
    /// giving a total length of `length * 2` bytes.
    /// Reverts if `length` is too small for the output to contain all the digits.
    function toHexStringNoPrefix(uint256 value, uint256 length)
        internal
        pure
        returns (string memory str)
    {
        /// @solidity memory-safe-assembly
        assembly {
            // We need 0x20 bytes for the trailing zeros padding, `length * 2` bytes
            // for the digits, 0x02 bytes for the prefix, and 0x20 bytes for the length.
            // We add 0x20 to the total and round down to a multiple of 0x20.
            // (0x20 + 0x20 + 0x02 + 0x20) = 0x62.
            str := add(mload(0x40), and(add(shl(1, length), 0x42), not(0x1f)))
            // Allocate the memory.
            mstore(0x40, add(str, 0x20))
            // Zeroize the slot after the string.
            mstore(str, 0)

            // Cache the end to calculate the length later.
            let end := str
            // Store "0123456789abcdef" in scratch space.
            mstore(0x0f, 0x30313233343536373839616263646566)

            let start := sub(str, add(length, length))
            let w := not(1) // Tsk.
            let temp := value
            // We write the string from rightmost digit to leftmost digit.
            // The following is essentially a do-while loop that also handles the zero case.
            for {} 1 {} {
                str := add(str, w) // `sub(str, 2)`.
                mstore8(add(str, 1), mload(and(temp, 15)))
                mstore8(str, mload(and(shr(4, temp), 15)))
                temp := shr(8, temp)
                if iszero(xor(str, start)) { break }
            }

            if temp {
                mstore(0x00, 0x2194895a) // `HexLengthInsufficient()`.
                revert(0x1c, 0x04)
            }

            // Compute the string's length.
            let strLength := sub(end, str)
            // Move the pointer and write the length.
            str := sub(str, 0x20)
            mstore(str, strLength)
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is prefixed with "0x" and encoded using 2 hexadecimal digits per byte.
    /// As address are 20 bytes long, the output will left-padded to have
    /// a length of `20 * 2 + 2` bytes.
    function toHexString(uint256 value) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(value);
        /// @solidity memory-safe-assembly
        assembly {
            let strLength := add(mload(str), 2) // Compute the length.
            mstore(str, 0x3078) // Write the "0x" prefix.
            str := sub(str, 2) // Move the pointer.
            mstore(str, strLength) // Write the length.
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is prefixed with "0x".
    /// The output excludes leading "0" from the `toHexString` output.
    /// `0x00: "0x0", 0x01: "0x1", 0x12: "0x12", 0x123: "0x123"`.
    function toMinimalHexString(uint256 value) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(value);
        /// @solidity memory-safe-assembly
        assembly {
            let o := eq(byte(0, mload(add(str, 0x20))), 0x30) // Whether leading zero is present.
            let strLength := add(mload(str), 2) // Compute the length.
            mstore(add(str, o), 0x3078) // Write the "0x" prefix, accounting for leading zero.
            str := sub(add(str, o), 2) // Move the pointer, accounting for leading zero.
            mstore(str, sub(strLength, o)) // Write the length, accounting for leading zero.
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output excludes leading "0" from the `toHexStringNoPrefix` output.
    /// `0x00: "0", 0x01: "1", 0x12: "12", 0x123: "123"`.
    function toMinimalHexStringNoPrefix(uint256 value) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(value);
        /// @solidity memory-safe-assembly
        assembly {
            let o := eq(byte(0, mload(add(str, 0x20))), 0x30) // Whether leading zero is present.
            let strLength := mload(str) // Get the length.
            str := add(str, o) // Move the pointer, accounting for leading zero.
            mstore(str, sub(strLength, o)) // Write the length, accounting for leading zero.
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is encoded using 2 hexadecimal digits per byte.
    /// As address are 20 bytes long, the output will left-padded to have
    /// a length of `20 * 2` bytes.
    function toHexStringNoPrefix(uint256 value) internal pure returns (string memory str) {
        /// @solidity memory-safe-assembly
        assembly {
            // We need 0x20 bytes for the trailing zeros padding, 0x20 bytes for the length,
            // 0x02 bytes for the prefix, and 0x40 bytes for the digits.
            // The next multiple of 0x20 above (0x20 + 0x20 + 0x02 + 0x40) is 0xa0.
            str := add(mload(0x40), 0x80)
            // Allocate the memory.
            mstore(0x40, add(str, 0x20))
            // Zeroize the slot after the string.
            mstore(str, 0)

            // Cache the end to calculate the length later.
            let end := str
            // Store "0123456789abcdef" in scratch space.
            mstore(0x0f, 0x30313233343536373839616263646566)

            let w := not(1) // Tsk.
            // We write the string from rightmost digit to leftmost digit.
            // The following is essentially a do-while loop that also handles the zero case.
            for { let temp := value } 1 {} {
                str := add(str, w) // `sub(str, 2)`.
                mstore8(add(str, 1), mload(and(temp, 15)))
                mstore8(str, mload(and(shr(4, temp), 15)))
                temp := shr(8, temp)
                if iszero(temp) { break }
            }

            // Compute the string's length.
            let strLength := sub(end, str)
            // Move the pointer and write the length.
            str := sub(str, 0x20)
            mstore(str, strLength)
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is prefixed with "0x", encoded using 2 hexadecimal digits per byte,
    /// and the alphabets are capitalized conditionally according to
    /// https://eips.ethereum.org/EIPS/eip-55
    function toHexStringChecksummed(address value) internal pure returns (string memory str) {
        str = toHexString(value);
        /// @solidity memory-safe-assembly
        assembly {
            let mask := shl(6, div(not(0), 255)) // `0b010000000100000000 ...`
            let o := add(str, 0x22)
            let hashed := and(keccak256(o, 40), mul(34, mask)) // `0b10001000 ... `
            let t := shl(240, 136) // `0b10001000 << 240`
            for { let i := 0 } 1 {} {
                mstore(add(i, i), mul(t, byte(i, hashed)))
                i := add(i, 1)
                if eq(i, 20) { break }
            }
            mstore(o, xor(mload(o), shr(1, and(mload(0x00), and(mload(o), mask)))))
            o := add(o, 0x20)
            mstore(o, xor(mload(o), shr(1, and(mload(0x20), and(mload(o), mask)))))
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is prefixed with "0x" and encoded using 2 hexadecimal digits per byte.
    function toHexString(address value) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(value);
        /// @solidity memory-safe-assembly
        assembly {
            let strLength := add(mload(str), 2) // Compute the length.
            mstore(str, 0x3078) // Write the "0x" prefix.
            str := sub(str, 2) // Move the pointer.
            mstore(str, strLength) // Write the length.
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is encoded using 2 hexadecimal digits per byte.
    function toHexStringNoPrefix(address value) internal pure returns (string memory str) {
        /// @solidity memory-safe-assembly
        assembly {
            str := mload(0x40)

            // Allocate the memory.
            // We need 0x20 bytes for the trailing zeros padding, 0x20 bytes for the length,
            // 0x02 bytes for the prefix, and 0x28 bytes for the digits.
            // The next multiple of 0x20 above (0x20 + 0x20 + 0x02 + 0x28) is 0x80.
            mstore(0x40, add(str, 0x80))

            // Store "0123456789abcdef" in scratch space.
            mstore(0x0f, 0x30313233343536373839616263646566)

            str := add(str, 2)
            mstore(str, 40)

            let o := add(str, 0x20)
            mstore(add(o, 40), 0)

            value := shl(96, value)

            // We write the string from rightmost digit to leftmost digit.
            // The following is essentially a do-while loop that also handles the zero case.
            for { let i := 0 } 1 {} {
                let p := add(o, add(i, i))
                let temp := byte(i, value)
                mstore8(add(p, 1), mload(and(temp, 15)))
                mstore8(p, mload(shr(4, temp)))
                i := add(i, 1)
                if eq(i, 20) { break }
            }
        }
    }

    /// @dev Returns the hex encoded string from the raw bytes.
    /// The output is encoded using 2 hexadecimal digits per byte.
    function toHexString(bytes memory raw) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(raw);
        /// @solidity memory-safe-assembly
        assembly {
            let strLength := add(mload(str), 2) // Compute the length.
            mstore(str, 0x3078) // Write the "0x" prefix.
            str := sub(str, 2) // Move the pointer.
            mstore(str, strLength) // Write the length.
        }
    }

    /// @dev Returns the hex encoded string from the raw bytes.
    /// The output is encoded using 2 hexadecimal digits per byte.
    function toHexStringNoPrefix(bytes memory raw) internal pure returns (string memory str) {
        /// @solidity memory-safe-assembly
        assembly {
            let length := mload(raw)
            str := add(mload(0x40), 2) // Skip 2 bytes for the optional prefix.
            mstore(str, add(length, length)) // Store the length of the output.

            // Store "0123456789abcdef" in scratch space.
            mstore(0x0f, 0x30313233343536373839616263646566)

            let o := add(str, 0x20)
            let end := add(raw, length)

            for {} iszero(eq(raw, end)) {} {
                raw := add(raw, 1)
                mstore8(add(o, 1), mload(and(mload(raw), 15)))
                mstore8(o, mload(and(shr(4, mload(raw)), 15)))
                o := add(o, 2)
            }
            mstore(o, 0) // Zeroize the slot after the string.
            mstore(0x40, add(o, 0x20)) // Allocate the memory.
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   RUNE STRING OPERATIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the number of UTF characters in the string.
    function runeCount(string memory s) internal pure returns (uint256 result) {
        /// @solidity memory-safe-assembly
        assembly {
            if mload(s) {
                mstore(0x00, div(not(0), 255))
                mstore(0x20, 0x0202020202020202020202020202020202020202020202020303030304040506)
                let o := add(s, 0x20)
                let end := add(o, mload(s))
                for { result := 1 } 1 { result := add(result, 1) } {
                    o := add(o, byte(0, mload(shr(250, mload(o)))))
                    if iszero(lt(o, end)) { break }
                }
            }
        }
    }

    /// @dev Returns if this string is a 7-bit ASCII string.
    /// (i.e. all characters codes are in [0..127])
    function is7BitASCII(string memory s) internal pure returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            let mask := shl(7, div(not(0), 255))
            result := 1
            let n := mload(s)
            if n {
                let o := add(s, 0x20)
                let end := add(o, n)
                let last := mload(end)
                mstore(end, 0)
                for {} 1 {} {
                    if and(mask, mload(o)) {
                        result := 0
                        break
                    }
                    o := add(o, 0x20)
                    if iszero(lt(o, end)) { break }
                }
                mstore(end, last)
            }
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   BYTE STRING OPERATIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    // For performance and bytecode compactness, byte string operations are restricted
    // to 7-bit ASCII strings. All offsets are byte offsets, not UTF character offsets.
    // Usage of byte string operations on charsets with runes spanning two or more bytes
    // can lead to undefined behavior.

    /// @dev Returns `subject` all occurrences of `search` replaced with `replacement`.
    function replace(string memory subject, string memory search, string memory replacement)
        internal
        pure
        returns (string memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let subjectLength := mload(subject)
            let searchLength := mload(search)
            let replacementLength := mload(replacement)

            subject := add(subject, 0x20)
            search := add(search, 0x20)
            replacement := add(replacement, 0x20)
            result := add(mload(0x40), 0x20)

            let subjectEnd := add(subject, subjectLength)
            if iszero(gt(searchLength, subjectLength)) {
                let subjectSearchEnd := add(sub(subjectEnd, searchLength), 1)
                let h := 0
                if iszero(lt(searchLength, 0x20)) { h := keccak256(search, searchLength) }
                let m := shl(3, sub(0x20, and(searchLength, 0x1f)))
                let s := mload(search)
                for {} 1 {} {
                    let t := mload(subject)
                    // Whether the first `searchLength % 32` bytes of
                    // `subject` and `search` matches.
                    if iszero(shr(m, xor(t, s))) {
                        if h {
                            if iszero(eq(keccak256(subject, searchLength), h)) {
                                mstore(result, t)
                                result := add(result, 1)
                                subject := add(subject, 1)
                                if iszero(lt(subject, subjectSearchEnd)) { break }
                                continue
                            }
                        }
                        // Copy the `replacement` one word at a time.
                        for { let o := 0 } 1 {} {
                            mstore(add(result, o), mload(add(replacement, o)))
                            o := add(o, 0x20)
                            if iszero(lt(o, replacementLength)) { break }
                        }
                        result := add(result, replacementLength)
                        subject := add(subject, searchLength)
                        if searchLength {
                            if iszero(lt(subject, subjectSearchEnd)) { break }
                            continue
                        }
                    }
                    mstore(result, t)
                    result := add(result, 1)
                    subject := add(subject, 1)
                    if iszero(lt(subject, subjectSearchEnd)) { break }
                }
            }

            let resultRemainder := result
            result := add(mload(0x40), 0x20)
            let k := add(sub(resultRemainder, result), sub(subjectEnd, subject))
            // Copy the rest of the string one word at a time.
            for {} lt(subject, subjectEnd) {} {
                mstore(resultRemainder, mload(subject))
                resultRemainder := add(resultRemainder, 0x20)
                subject := add(subject, 0x20)
            }
            result := sub(result, 0x20)
            let last := add(add(result, 0x20), k) // Zeroize the slot after the string.
            mstore(last, 0)
            mstore(0x40, add(last, 0x20)) // Allocate the memory.
            mstore(result, k) // Store the length.
        }
    }

    /// @dev Returns the byte index of the first location of `search` in `subject`,
    /// searching from left to right, starting from `from`.
    /// Returns `NOT_FOUND` (i.e. `type(uint256).max`) if the `search` is not found.
    function indexOf(string memory subject, string memory search, uint256 from)
        internal
        pure
        returns (uint256 result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            for { let subjectLength := mload(subject) } 1 {} {
                if iszero(mload(search)) {
                    if iszero(gt(from, subjectLength)) {
                        result := from
                        break
                    }
                    result := subjectLength
                    break
                }
                let searchLength := mload(search)
                let subjectStart := add(subject, 0x20)

                result := not(0) // Initialize to `NOT_FOUND`.

                subject := add(subjectStart, from)
                let end := add(sub(add(subjectStart, subjectLength), searchLength), 1)

                let m := shl(3, sub(0x20, and(searchLength, 0x1f)))
                let s := mload(add(search, 0x20))

                if iszero(and(lt(subject, end), lt(from, subjectLength))) { break }

                if iszero(lt(searchLength, 0x20)) {
                    for { let h := keccak256(add(search, 0x20), searchLength) } 1 {} {
                        if iszero(shr(m, xor(mload(subject), s))) {
                            if eq(keccak256(subject, searchLength), h) {
                                result := sub(subject, subjectStart)
                                break
                            }
                        }
                        subject := add(subject, 1)
                        if iszero(lt(subject, end)) { break }
                    }
                    break
                }
                for {} 1 {} {
                    if iszero(shr(m, xor(mload(subject), s))) {
                        result := sub(subject, subjectStart)
                        break
                    }
                    subject := add(subject, 1)
                    if iszero(lt(subject, end)) { break }
                }
                break
            }
        }
    }

    /// @dev Returns the byte index of the first location of `search` in `subject`,
    /// searching from left to right.
    /// Returns `NOT_FOUND` (i.e. `type(uint256).max`) if the `search` is not found.
    function indexOf(string memory subject, string memory search)
        internal
        pure
        returns (uint256 result)
    {
        result = indexOf(subject, search, 0);
    }

    /// @dev Returns the byte index of the first location of `search` in `subject`,
    /// searching from right to left, starting from `from`.
    /// Returns `NOT_FOUND` (i.e. `type(uint256).max`) if the `search` is not found.
    function lastIndexOf(string memory subject, string memory search, uint256 from)
        internal
        pure
        returns (uint256 result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            for {} 1 {} {
                result := not(0) // Initialize to `NOT_FOUND`.
                let searchLength := mload(search)
                if gt(searchLength, mload(subject)) { break }
                let w := result

                let fromMax := sub(mload(subject), searchLength)
                if iszero(gt(fromMax, from)) { from := fromMax }

                let end := add(add(subject, 0x20), w)
                subject := add(add(subject, 0x20), from)
                if iszero(gt(subject, end)) { break }
                // As this function is not too often used,
                // we shall simply use keccak256 for smaller bytecode size.
                for { let h := keccak256(add(search, 0x20), searchLength) } 1 {} {
                    if eq(keccak256(subject, searchLength), h) {
                        result := sub(subject, add(end, 1))
                        break
                    }
                    subject := add(subject, w) // `sub(subject, 1)`.
                    if iszero(gt(subject, end)) { break }
                }
                break
            }
        }
    }

    /// @dev Returns the byte index of the first location of `search` in `subject`,
    /// searching from right to left.
    /// Returns `NOT_FOUND` (i.e. `type(uint256).max`) if the `search` is not found.
    function lastIndexOf(string memory subject, string memory search)
        internal
        pure
        returns (uint256 result)
    {
        result = lastIndexOf(subject, search, uint256(int256(-1)));
    }

    /// @dev Returns true if `search` is found in `subject`, false otherwise.
    function contains(string memory subject, string memory search) internal pure returns (bool) {
        return indexOf(subject, search) != NOT_FOUND;
    }

    /// @dev Returns whether `subject` starts with `search`.
    function startsWith(string memory subject, string memory search)
        internal
        pure
        returns (bool result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let searchLength := mload(search)
            // Just using keccak256 directly is actually cheaper.
            // forgefmt: disable-next-item
            result := and(
                iszero(gt(searchLength, mload(subject))),
                eq(
                    keccak256(add(subject, 0x20), searchLength),
                    keccak256(add(search, 0x20), searchLength)
                )
            )
        }
    }

    /// @dev Returns whether `subject` ends with `search`.
    function endsWith(string memory subject, string memory search)
        internal
        pure
        returns (bool result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let searchLength := mload(search)
            let subjectLength := mload(subject)
            // Whether `search` is not longer than `subject`.
            let withinRange := iszero(gt(searchLength, subjectLength))
            // Just using keccak256 directly is actually cheaper.
            // forgefmt: disable-next-item
            result := and(
                withinRange,
                eq(
                    keccak256(
                        // `subject + 0x20 + max(subjectLength - searchLength, 0)`.
                        add(add(subject, 0x20), mul(withinRange, sub(subjectLength, searchLength))),
                        searchLength
                    ),
                    keccak256(add(search, 0x20), searchLength)
                )
            )
        }
    }

    /// @dev Returns `subject` repeated `times`.
    function repeat(string memory subject, uint256 times)
        internal
        pure
        returns (string memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let subjectLength := mload(subject)
            if iszero(or(iszero(times), iszero(subjectLength))) {
                subject := add(subject, 0x20)
                result := mload(0x40)
                let output := add(result, 0x20)
                for {} 1 {} {
                    // Copy the `subject` one word at a time.
                    for { let o := 0 } 1 {} {
                        mstore(add(output, o), mload(add(subject, o)))
                        o := add(o, 0x20)
                        if iszero(lt(o, subjectLength)) { break }
                    }
                    output := add(output, subjectLength)
                    times := sub(times, 1)
                    if iszero(times) { break }
                }
                mstore(output, 0) // Zeroize the slot after the string.
                let resultLength := sub(output, add(result, 0x20))
                mstore(result, resultLength) // Store the length.
                // Allocate the memory.
                mstore(0x40, add(result, add(resultLength, 0x20)))
            }
        }
    }

    /// @dev Returns a copy of `subject` sliced from `start` to `end` (exclusive).
    /// `start` and `end` are byte offsets.
    function slice(string memory subject, uint256 start, uint256 end)
        internal
        pure
        returns (string memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let subjectLength := mload(subject)
            if iszero(gt(subjectLength, end)) { end := subjectLength }
            if iszero(gt(subjectLength, start)) { start := subjectLength }
            if lt(start, end) {
                result := mload(0x40)
                let resultLength := sub(end, start)
                mstore(result, resultLength)
                subject := add(subject, start)
                let w := not(0x1f)
                // Copy the `subject` one word at a time, backwards.
                for { let o := and(add(resultLength, 0x1f), w) } 1 {} {
                    mstore(add(result, o), mload(add(subject, o)))
                    o := add(o, w) // `sub(o, 0x20)`.
                    if iszero(o) { break }
                }
                // Zeroize the slot after the string.
                mstore(add(add(result, 0x20), resultLength), 0)
                // Allocate memory for the length and the bytes,
                // rounded up to a multiple of 32.
                mstore(0x40, add(result, and(add(resultLength, 0x3f), w)))
            }
        }
    }

    /// @dev Returns a copy of `subject` sliced from `start` to the end of the string.
    /// `start` is a byte offset.
    function slice(string memory subject, uint256 start)
        internal
        pure
        returns (string memory result)
    {
        result = slice(subject, start, uint256(int256(-1)));
    }

    /// @dev Returns all the indices of `search` in `subject`.
    /// The indices are byte offsets.
    function indicesOf(string memory subject, string memory search)
        internal
        pure
        returns (uint256[] memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let subjectLength := mload(subject)
            let searchLength := mload(search)

            if iszero(gt(searchLength, subjectLength)) {
                subject := add(subject, 0x20)
                search := add(search, 0x20)
                result := add(mload(0x40), 0x20)

                let subjectStart := subject
                let subjectSearchEnd := add(sub(add(subject, subjectLength), searchLength), 1)
                let h := 0
                if iszero(lt(searchLength, 0x20)) { h := keccak256(search, searchLength) }
                let m := shl(3, sub(0x20, and(searchLength, 0x1f)))
                let s := mload(search)
                for {} 1 {} {
                    let t := mload(subject)
                    // Whether the first `searchLength % 32` bytes of
                    // `subject` and `search` matches.
                    if iszero(shr(m, xor(t, s))) {
                        if h {
                            if iszero(eq(keccak256(subject, searchLength), h)) {
                                subject := add(subject, 1)
                                if iszero(lt(subject, subjectSearchEnd)) { break }
                                continue
                            }
                        }
                        // Append to `result`.
                        mstore(result, sub(subject, subjectStart))
                        result := add(result, 0x20)
                        // Advance `subject` by `searchLength`.
                        subject := add(subject, searchLength)
                        if searchLength {
                            if iszero(lt(subject, subjectSearchEnd)) { break }
                            continue
                        }
                    }
                    subject := add(subject, 1)
                    if iszero(lt(subject, subjectSearchEnd)) { break }
                }
                let resultEnd := result
                // Assign `result` to the free memory pointer.
                result := mload(0x40)
                // Store the length of `result`.
                mstore(result, shr(5, sub(resultEnd, add(result, 0x20))))
                // Allocate memory for result.
                // We allocate one more word, so this array can be recycled for {split}.
                mstore(0x40, add(resultEnd, 0x20))
            }
        }
    }

    /// @dev Returns a arrays of strings based on the `delimiter` inside of the `subject` string.
    function split(string memory subject, string memory delimiter)
        internal
        pure
        returns (string[] memory result)
    {
        uint256[] memory indices = indicesOf(subject, delimiter);
        /// @solidity memory-safe-assembly
        assembly {
            let w := not(0x1f)
            let indexPtr := add(indices, 0x20)
            let indicesEnd := add(indexPtr, shl(5, add(mload(indices), 1)))
            mstore(add(indicesEnd, w), mload(subject))
            mstore(indices, add(mload(indices), 1))
            let prevIndex := 0
            for {} 1 {} {
                let index := mload(indexPtr)
                mstore(indexPtr, 0x60)
                if iszero(eq(index, prevIndex)) {
                    let element := mload(0x40)
                    let elementLength := sub(index, prevIndex)
                    mstore(element, elementLength)
                    // Copy the `subject` one word at a time, backwards.
                    for { let o := and(add(elementLength, 0x1f), w) } 1 {} {
                        mstore(add(element, o), mload(add(add(subject, prevIndex), o)))
                        o := add(o, w) // `sub(o, 0x20)`.
                        if iszero(o) { break }
                    }
                    // Zeroize the slot after the string.
                    mstore(add(add(element, 0x20), elementLength), 0)
                    // Allocate memory for the length and the bytes,
                    // rounded up to a multiple of 32.
                    mstore(0x40, add(element, and(add(elementLength, 0x3f), w)))
                    // Store the `element` into the array.
                    mstore(indexPtr, element)
                }
                prevIndex := add(index, mload(delimiter))
                indexPtr := add(indexPtr, 0x20)
                if iszero(lt(indexPtr, indicesEnd)) { break }
            }
            result := indices
            if iszero(mload(delimiter)) {
                result := add(indices, 0x20)
                mstore(result, sub(mload(indices), 2))
            }
        }
    }

    /// @dev Returns a concatenated string of `a` and `b`.
    /// Cheaper than `string.concat()` and does not de-align the free memory pointer.
    function concat(string memory a, string memory b)
        internal
        pure
        returns (string memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let w := not(0x1f)
            result := mload(0x40)
            let aLength := mload(a)
            // Copy `a` one word at a time, backwards.
            for { let o := and(add(aLength, 0x20), w) } 1 {} {
                mstore(add(result, o), mload(add(a, o)))
                o := add(o, w) // `sub(o, 0x20)`.
                if iszero(o) { break }
            }
            let bLength := mload(b)
            let output := add(result, aLength)
            // Copy `b` one word at a time, backwards.
            for { let o := and(add(bLength, 0x20), w) } 1 {} {
                mstore(add(output, o), mload(add(b, o)))
                o := add(o, w) // `sub(o, 0x20)`.
                if iszero(o) { break }
            }
            let totalLength := add(aLength, bLength)
            let last := add(add(result, 0x20), totalLength)
            // Zeroize the slot after the string.
            mstore(last, 0)
            // Stores the length.
            mstore(result, totalLength)
            // Allocate memory for the length and the bytes,
            // rounded up to a multiple of 32.
            mstore(0x40, and(add(last, 0x1f), w))
        }
    }

    /// @dev Returns a copy of the string in either lowercase or UPPERCASE.
    /// WARNING! This function is only compatible with 7-bit ASCII strings.
    function toCase(string memory subject, bool toUpper)
        internal
        pure
        returns (string memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let length := mload(subject)
            if length {
                result := add(mload(0x40), 0x20)
                subject := add(subject, 1)
                let flags := shl(add(70, shl(5, toUpper)), 0x3ffffff)
                let w := not(0)
                for { let o := length } 1 {} {
                    o := add(o, w)
                    let b := and(0xff, mload(add(subject, o)))
                    mstore8(add(result, o), xor(b, and(shr(b, flags), 0x20)))
                    if iszero(o) { break }
                }
                result := mload(0x40)
                mstore(result, length) // Store the length.
                let last := add(add(result, 0x20), length)
                mstore(last, 0) // Zeroize the slot after the string.
                mstore(0x40, add(last, 0x20)) // Allocate the memory.
            }
        }
    }

    /// @dev Returns a string from a small bytes32 string.
    /// `s` must be null-terminated, or behavior will be undefined.
    function fromSmallString(bytes32 s) internal pure returns (string memory result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := mload(0x40)
            let n := 0
            for {} byte(n, s) { n := add(n, 1) } {} // Scan for '\0'.
            mstore(result, n)
            let o := add(result, 0x20)
            mstore(o, s)
            mstore(add(o, n), 0)
            mstore(0x40, add(result, 0x40))
        }
    }

    /// @dev Returns the small string, with all bytes after the first null byte zeroized.
    function normalizeSmallString(bytes32 s) internal pure returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            for {} byte(result, s) { result := add(result, 1) } {} // Scan for '\0'.
            mstore(0x00, s)
            mstore(result, 0x00)
            result := mload(0x00)
        }
    }

    /// @dev Returns the string as a normalized null-terminated small string.
    function toSmallString(string memory s) internal pure returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := mload(s)
            if iszero(lt(result, 33)) {
                mstore(0x00, 0xec92f9a3) // `TooBigForSmallString()`.
                revert(0x1c, 0x04)
            }
            result := shl(shl(3, sub(32, result)), mload(add(s, result)))
        }
    }

    /// @dev Returns a lowercased copy of the string.
    /// WARNING! This function is only compatible with 7-bit ASCII strings.
    function lower(string memory subject) internal pure returns (string memory result) {
        result = toCase(subject, false);
    }

    /// @dev Returns an UPPERCASED copy of the string.
    /// WARNING! This function is only compatible with 7-bit ASCII strings.
    function upper(string memory subject) internal pure returns (string memory result) {
        result = toCase(subject, true);
    }

    /// @dev Escapes the string to be used within HTML tags.
    function escapeHTML(string memory s) internal pure returns (string memory result) {
        /// @solidity memory-safe-assembly
        assembly {
            let end := add(s, mload(s))
            result := add(mload(0x40), 0x20)
            // Store the bytes of the packed offsets and strides into the scratch space.
            // `packed = (stride << 5) | offset`. Max offset is 20. Max stride is 6.
            mstore(0x1f, 0x900094)
            mstore(0x08, 0xc0000000a6ab)
            // Store "&quot;&amp;&#39;&lt;&gt;" into the scratch space.
            mstore(0x00, shl(64, 0x2671756f743b26616d703b262333393b266c743b2667743b))
            for {} iszero(eq(s, end)) {} {
                s := add(s, 1)
                let c := and(mload(s), 0xff)
                // Not in `["\"","'","&","<",">"]`.
                if iszero(and(shl(c, 1), 0x500000c400000000)) {
                    mstore8(result, c)
                    result := add(result, 1)
                    continue
                }
                let t := shr(248, mload(c))
                mstore(result, mload(and(t, 0x1f)))
                result := add(result, shr(5, t))
            }
            let last := result
            mstore(last, 0) // Zeroize the slot after the string.
            result := mload(0x40)
            mstore(result, sub(last, add(result, 0x20))) // Store the length.
            mstore(0x40, add(last, 0x20)) // Allocate the memory.
        }
    }

    /// @dev Escapes the string to be used within double-quotes in a JSON.
    /// If `addDoubleQuotes` is true, the result will be enclosed in double-quotes.
    function escapeJSON(string memory s, bool addDoubleQuotes)
        internal
        pure
        returns (string memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let end := add(s, mload(s))
            result := add(mload(0x40), 0x20)
            if addDoubleQuotes {
                mstore8(result, 34)
                result := add(1, result)
            }
            // Store "\\u0000" in scratch space.
            // Store "0123456789abcdef" in scratch space.
            // Also, store `{0x08:"b", 0x09:"t", 0x0a:"n", 0x0c:"f", 0x0d:"r"}`.
            // into the scratch space.
            mstore(0x15, 0x5c75303030303031323334353637383961626364656662746e006672)
            // Bitmask for detecting `["\"","\\"]`.
            let e := or(shl(0x22, 1), shl(0x5c, 1))
            for {} iszero(eq(s, end)) {} {
                s := add(s, 1)
                let c := and(mload(s), 0xff)
                if iszero(lt(c, 0x20)) {
                    if iszero(and(shl(c, 1), e)) {
                        // Not in `["\"","\\"]`.
                        mstore8(result, c)
                        result := add(result, 1)
                        continue
                    }
                    mstore8(result, 0x5c) // "\\".
                    mstore8(add(result, 1), c)
                    result := add(result, 2)
                    continue
                }
                if iszero(and(shl(c, 1), 0x3700)) {
                    // Not in `["\b","\t","\n","\f","\d"]`.
                    mstore8(0x1d, mload(shr(4, c))) // Hex value.
                    mstore8(0x1e, mload(and(c, 15))) // Hex value.
                    mstore(result, mload(0x19)) // "\\u00XX".
                    result := add(result, 6)
                    continue
                }
                mstore8(result, 0x5c) // "\\".
                mstore8(add(result, 1), mload(add(c, 8)))
                result := add(result, 2)
            }
            if addDoubleQuotes {
                mstore8(result, 34)
                result := add(1, result)
            }
            let last := result
            mstore(last, 0) // Zeroize the slot after the string.
            result := mload(0x40)
            mstore(result, sub(last, add(result, 0x20))) // Store the length.
            mstore(0x40, add(last, 0x20)) // Allocate the memory.
        }
    }

    /// @dev Escapes the string to be used within double-quotes in a JSON.
    function escapeJSON(string memory s) internal pure returns (string memory result) {
        result = escapeJSON(s, false);
    }

    /// @dev Returns whether `a` equals `b`.
    function eq(string memory a, string memory b) internal pure returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := eq(keccak256(add(a, 0x20), mload(a)), keccak256(add(b, 0x20), mload(b)))
        }
    }

    /// @dev Returns whether `a` equals `b`, where `b` is a null-terminated small string.
    function eqs(string memory a, bytes32 b) internal pure returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            // These should be evaluated on compile time, as far as possible.
            let m := not(shl(7, div(not(iszero(b)), 255))) // `0x7f7f ...`.
            let x := not(or(m, or(b, add(m, and(b, m)))))
            let r := shl(7, iszero(iszero(shr(128, x))))
            r := or(r, shl(6, iszero(iszero(shr(64, shr(r, x))))))
            r := or(r, shl(5, lt(0xffffffff, shr(r, x))))
            r := or(r, shl(4, lt(0xffff, shr(r, x))))
            r := or(r, shl(3, lt(0xff, shr(r, x))))
            // forgefmt: disable-next-item
            result := gt(eq(mload(a), add(iszero(x), xor(31, shr(3, r)))),
                xor(shr(add(8, r), b), shr(add(8, r), mload(add(a, 0x20)))))
        }
    }

    /// @dev Packs a single string with its length into a single word.
    /// Returns `bytes32(0)` if the length is zero or greater than 31.
    function packOne(string memory a) internal pure returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            // We don't need to zero right pad the string,
            // since this is our own custom non-standard packing scheme.
            result :=
                mul(
                    // Load the length and the bytes.
                    mload(add(a, 0x1f)),
                    // `length != 0 && length < 32`. Abuses underflow.
                    // Assumes that the length is valid and within the block gas limit.
                    lt(sub(mload(a), 1), 0x1f)
                )
        }
    }

    /// @dev Unpacks a string packed using {packOne}.
    /// Returns the empty string if `packed` is `bytes32(0)`.
    /// If `packed` is not an output of {packOne}, the output behavior is undefined.
    function unpackOne(bytes32 packed) internal pure returns (string memory result) {
        /// @solidity memory-safe-assembly
        assembly {
            // Grab the free memory pointer.
            result := mload(0x40)
            // Allocate 2 words (1 for the length, 1 for the bytes).
            mstore(0x40, add(result, 0x40))
            // Zeroize the length slot.
            mstore(result, 0)
            // Store the length and bytes.
            mstore(add(result, 0x1f), packed)
            // Right pad with zeroes.
            mstore(add(add(result, 0x20), mload(result)), 0)
        }
    }

    /// @dev Packs two strings with their lengths into a single word.
    /// Returns `bytes32(0)` if combined length is zero or greater than 30.
    function packTwo(string memory a, string memory b) internal pure returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            let aLength := mload(a)
            // We don't need to zero right pad the strings,
            // since this is our own custom non-standard packing scheme.
            result :=
                mul(
                    // Load the length and the bytes of `a` and `b`.
                    or(
                        shl(shl(3, sub(0x1f, aLength)), mload(add(a, aLength))),
                        mload(sub(add(b, 0x1e), aLength))
                    ),
                    // `totalLength != 0 && totalLength < 31`. Abuses underflow.
                    // Assumes that the lengths are valid and within the block gas limit.
                    lt(sub(add(aLength, mload(b)), 1), 0x1e)
                )
        }
    }

    /// @dev Unpacks strings packed using {packTwo}.
    /// Returns the empty strings if `packed` is `bytes32(0)`.
    /// If `packed` is not an output of {packTwo}, the output behavior is undefined.
    function unpackTwo(bytes32 packed)
        internal
        pure
        returns (string memory resultA, string memory resultB)
    {
        /// @solidity memory-safe-assembly
        assembly {
            // Grab the free memory pointer.
            resultA := mload(0x40)
            resultB := add(resultA, 0x40)
            // Allocate 2 words for each string (1 for the length, 1 for the byte). Total 4 words.
            mstore(0x40, add(resultB, 0x40))
            // Zeroize the length slots.
            mstore(resultA, 0)
            mstore(resultB, 0)
            // Store the lengths and bytes.
            mstore(add(resultA, 0x1f), packed)
            mstore(add(resultB, 0x1f), mload(add(add(resultA, 0x20), mload(resultA))))
            // Right pad with zeroes.
            mstore(add(add(resultA, 0x20), mload(resultA)), 0)
            mstore(add(add(resultB, 0x20), mload(resultB)), 0)
        }
    }

    /// @dev Directly returns `a` without copying.
    function directReturn(string memory a) internal pure {
        assembly {
            // Assumes that the string does not start from the scratch space.
            let retStart := sub(a, 0x20)
            let retUnpaddedSize := add(mload(a), 0x40)
            // Right pad with zeroes. Just in case the string is produced
            // by a method that doesn't zero right pad.
            mstore(add(retStart, retUnpaddedSize), 0)
            // Store the return offset.
            mstore(retStart, 0x20)
            // End the transaction, returning the string.
            return(retStart, and(not(0x1f), add(0x1f, retUnpaddedSize)))
        }
    }
}