// File: contracts/ShufflerToken.sol



// SPDX-License-Identifier: GPL-3.0
// Modified from nouns.wtf

/// @title The Onchain Shuffler ERC-721A token

/**************************************************************************
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***************************************************************************/

pragma solidity ^0.8.6;

import { Ownable } from '@openzeppelin/contracts/access/Ownable.sol';
import { IERC721 } from '@openzeppelin/contracts/interfaces/IERC721.sol';
import { ERC721A } from "erc721a/contracts/ERC721A.sol";
import { IShufflerToken } from './interfaces/IShufflerToken.sol';
import { ReentrancyGuard } from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import { MerkleProof } from "@openzeppelin/contracts/utils/cryptography/MerkleProof.sol";
import { Strings } from "@openzeppelin/contracts/utils/Strings.sol";
import { IShufflerDescriptor } from './interfaces/IShufflerDescriptor.sol';
import { Base64 } from './libs/base64.sol';
import { OriginalPunkProxy } from "./OriginalPunkProxy.sol";

contract ShufflerToken is ERC721A, IShufflerToken, Ownable, ReentrancyGuard {
    // The treasury address (creators org)
    address payable public treasury;

    // The token URI descriptor
    IShufflerDescriptor public descriptor;

    // merkle root for whitelisting
    bytes32 public merkleRoot;

    // Whether the descriptor can be updated
    bool public isDescriptorLocked = false;

    // whether the seeds are locked(fully populated)
    bool public override areSeedsLocked = false;

    // whether the blind box is revealed
    bool public isRevealed = false;

    bool public isPublicSaleStarted = false;

    bool public isWhitelistSaleStarted = false;

    uint64 private seedsOffset;

    uint256 public composePrice = 0.01 ether;

    // a few more constants for minting
    uint64 public constant MAX_SUPPLY = 10000;
    uint64 public constant MAX_PER_MINT = 20;
    uint64 public constant MAX_PRESALE_SUPPLY = 3000;
    uint256 public constant MINT_PRICE = 0.08 ether;
    uint256 public constant WHITELIST_MINT_PRICE = 0.06 ether;
    // contracts constants
    address public constant PUNK_ORIGINAL_CONTRACT = address(0xb47e3cd837dDF8e4c57F05d70Ab865de6e193BBB);
    // mint count by owner
    mapping(address => uint256) private _alreadyMinted;
    // seeds for tokens
    Seed[] private seeds;
    // IPFS content hash of contract-level metadata
    string private _contractURIHash = 'bafkreigxg3pqah7tlc2ny2hyffjwm7qttxloctuhmabzzklkovgrnaxuya';

    /**
     * @notice Require that the seeds has not been locked.
     */
    modifier whenSeedsNotLocked() {
        require(!areSeedsLocked, 'Seeds are locked');
        _;
    }
    /**
     * @notice Require that the descriptor has not been locked.
     */
    modifier whenDescriptorNotLocked() {
        require(!isDescriptorLocked, 'Descriptor is locked');
        _;
    }

    constructor(
        address payable _treasury,
        IShufflerDescriptor _descriptor
    ) ERC721A('Onchain Shufflers', 'ONCHAIN SHUFFLERS') {
        treasury = _treasury;
        descriptor = _descriptor;
    }

    /**
     * @notice update treasury address
     */
    function setTreasury(address payable _treasury) external override onlyOwner {
        treasury = _treasury;
    }

    /**
     * @notice Lock the seeds
     * @dev This cannot be reversed and is only callable by the owner when not locked.
     */
    function lockSeeds() external override onlyOwner whenSeedsNotLocked {
        areSeedsLocked = true;

        emit SeedsLocked();
    }

    /**
     * @notice Batch add seeds
     * @dev This function can only be called by the owner when not locked.
     */
    function addManySeeds(uint256[] calldata _seeds) external override onlyOwner whenSeedsNotLocked {
        for (uint256 i = 0; i < _seeds.length; i++) {
            Seed memory seed = Seed({
                background: uint48(
                    uint48(_seeds[i])
                ),
                card: uint48(
                    uint48(_seeds[i] >> 48)
                ),
                side: uint48(
                    uint48(_seeds[i] >> 96)
                ),
                corner: uint48(
                    uint48(_seeds[i] >> 144)
                ),
                center: uint48(
                    uint48(_seeds[i] >> 192)
                ),
                override_contract: address(0),
                override_token_id: 0
            });
            seeds.push(seed);
        }
        emit SeedsAdded(_seeds);
    }

    function seedCount() external view override returns (uint256) {
        return seeds.length;
    }

    /**
     * @notice The IPFS URI of contract-level metadata.
     */
    function contractURI() public view returns (string memory) {
        return string(abi.encodePacked('ipfs://', _contractURIHash));
    }

    /**
     * @notice Set the _contractURIHash.
     * @dev Only callable by the owner.
     */
    function setContractURIHash(string memory newContractURIHash) external onlyOwner {
        _contractURIHash = newContractURIHash;
    }

    /**
     * @notice toggle on/off the public sale switch
     */
    function setPublicSaleStatus(bool status) external onlyOwner {
        isPublicSaleStarted = status;
    }

    /**
     * @notice toggle on/off the whitelist sale switch
     */
    function setWhitelistSaleStatus(bool status) external onlyOwner {
        isWhitelistSaleStarted = status;
    }

    /**
     * @notice update merkle root
     */
    function setMerkleRoot(bytes32 _merkleRoot) external onlyOwner {
        merkleRoot = _merkleRoot;
    }

    /**
     * @notice reveal all blind boxes
     */
    function reveal() external override onlyOwner {
        require(!isRevealed, "already revealed");
        require(areSeedsLocked, "can't reveal before seeds are locked");
        isRevealed = true;
        // start from a random position to assign randomness when revealing the cards
        seedsOffset = uint64(uint(keccak256(abi.encodePacked(block.difficulty, block.timestamp)))) % MAX_SUPPLY;
        emit Reveal(seedsOffset);
        // enable rendering svg images instead of showing the blind box
        descriptor.toggleDataURIEnabled();
    }

    /**
     * @notice Mint a Shuffler token to the messenger sender
     */
    function mint(uint256 count) external payable nonReentrant override {
        require(isPublicSaleStarted, "Public sale not started yet");
        require(count > 0 && count <= MAX_PER_MINT, "Invalid number to mint");
        require(count * MINT_PRICE <= msg.value, "Incorrect amount of ether sent");

        _internalMint(_msgSenderERC721A(), count);
    }

    /**
      * @notice Mint by owner for free
     */
    function ownerMint(address to, uint256 count) external onlyOwner override{
        _internalMint(to, count);
    }

    /**
     * @notice Mint by whitelisted users
     */
    function mintWhiteList(
        uint256 count,
        uint256 maxCount,
        bytes32[] calldata merkleProof
    ) external payable nonReentrant override {
        address sender = _msgSenderERC721A();

        require(isWhitelistSaleStarted, "Whitelist sale not started");
        require(_verify(merkleProof, sender, maxCount), "Wallet not whitelisted");
        require(_nextTokenId() + count <= MAX_PRESALE_SUPPLY, "Will exceed maximum presale supply");
        require(count <= maxCount - _alreadyMinted[sender], "Insufficient mints left");
        require(count * WHITELIST_MINT_PRICE <= msg.value, "Incorrect payable amount");

        _alreadyMinted[sender] += count;
        _internalMint(sender, count);
    }

    function _internalMint(address to, uint256 count) private {
        require(_nextTokenId() + count <= MAX_SUPPLY, "Will exceed maximum supply");

        uint256 startTokenId = _nextTokenId();
        _mint(to, count);
        emit ShufflerCreated(_msgSenderERC721A(), startTokenId, startTokenId + count - 1);
    }

    function _verify(
        bytes32[] calldata merkleProof,
        address sender,
        uint256 maxCount
    ) private view returns (bool) {
        bytes32 leaf = keccak256(abi.encodePacked(sender, maxCount));
        return MerkleProof.verify(merkleProof, merkleRoot, leaf);
    }

    function seedId(uint256 tokenId) internal view returns (uint256) {
        require(seeds.length > 0, "Seeds not ready");
        return (tokenId + seedsOffset) % seeds.length;
    }

    function getSeed(uint256 tokenId) external view returns (Seed memory) {
        require(_exists(tokenId), 'ShufflerToken: URI query for nonexistent token');
        return seeds[seedId(tokenId)];
    }

    /**
     * @notice A distinct Uniform Resource Identifier (URI) for a given asset.
     * @dev See {IERC721Metadata-tokenURI}.
     */
    function tokenURI(uint256 tokenId) public view override returns (string memory) {
        require(_exists(tokenId), 'ShufflerToken: URI query for nonexistent token');
        if (isRevealed) {
            return descriptor.tokenURI(tokenId, seeds[seedId(tokenId)]);
        } else {
            return string(
                abi.encodePacked(
                    'data:application/json;base64,',
                    Base64.encode(
                        bytes(
                            abi.encodePacked('{"name":"Shuffler #', Strings.toString(tokenId), '", "image": "', descriptor.baseURI(), '"}')
                        )
                    )
                )
            );
        }
    }

    /**
     * @notice Set the token URI descriptor.
     * @dev Only callable by the owner when not locked.
     */
    function setDescriptor(IShufflerDescriptor _descriptor) external override onlyOwner whenDescriptorNotLocked {
        descriptor = _descriptor;

        emit DescriptorUpdated(_descriptor);
    }

    /**
     * @notice Lock the descriptor.
     * @dev This cannot be reversed and is only callable by the owner when not locked.
     */
    function lockDescriptor() external override onlyOwner whenDescriptorNotLocked {
        isDescriptorLocked = true;

        emit DescriptorLocked();
    }

    /**
     * @notice withdraw the contract assets to treasury
     */
    function withdraw() external override {
        uint amount = address(this).balance;
        require(amount > 0, "no ethers to withdraw");
        treasury.transfer(amount);
    }

    /**
     * @notice set new compose price
     */
    function setComposePrice(uint256 _price) external override onlyOwner {
        composePrice = _price;
    }

    /**
     * @notice override the center part of card with a third-party nft specified by its
     * contract address and token id
     */
    function setOverrideNft(uint256 tokenId, address overrideContract, uint64 overrideTokenId) external payable override {
        require(_exists(tokenId), 'Nonexistent token can not be modified');
        require(isRevealed, 'Token not revealed yet');
        require(_msgSenderERC721A() == ownerOf(tokenId), 'Only owner can update the shuffler');
        require(msg.value >= composePrice, 'Invalid amount paid for composing');
        require(descriptor.isComposable(overrideContract), 'Unsupported contract for composing');
        require(_verifyOwnerOfOverride(overrideContract, overrideTokenId), 'Only owner of the target token can compose');

        _updateNftOverride(tokenId, overrideContract, overrideTokenId);
    }

    function removeOverrideNft(uint256 tokenId) external override {
        require(_exists(tokenId), 'Nonexistent token can not be modified');
        require(isRevealed, 'Token not revealed yet');
        require(_msgSenderERC721A() == ownerOf(tokenId), 'Only owner can update the shuffler');

        _updateNftOverride(tokenId, address(0x0), 0);
    }

    function _updateNftOverride(uint256 tokenId, address overrideContract, uint64 overrideTokenId) private {
        uint256 curSeedId = seedId(tokenId);
        seeds[curSeedId].override_contract = overrideContract;
        seeds[curSeedId].override_token_id = overrideTokenId;

        emit NftOverridden(tokenId, overrideContract, overrideTokenId);
    }

    function _verifyOwnerOfOverride(address overrideContract, uint64 overrideTokenId) internal view returns (bool) {
        if (overrideContract == PUNK_ORIGINAL_CONTRACT) {
            // original punk contract is not ERC721
            OriginalPunkProxy otherContract = OriginalPunkProxy(overrideContract);
            return otherContract.punkIndexToAddress(overrideTokenId) == _msgSenderERC721A();
        } else {
            IERC721 otherContract = IERC721(overrideContract);
            return otherContract.ownerOf(overrideTokenId) == _msgSenderERC721A();
        }
    }
}

// File: @openzeppelin/contracts/access/Ownable.sol



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

pragma solidity ^0.8.0;

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

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

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

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

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

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

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

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

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

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

// File: @openzeppelin/contracts/interfaces/IERC721.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (interfaces/IERC721.sol)

pragma solidity ^0.8.0;

import "../token/ERC721/IERC721.sol";

// File: erc721a/contracts/ERC721A.sol



// SPDX-License-Identifier: MIT
// ERC721A Contracts v4.2.2
// Creator: Chiru Labs

pragma solidity ^0.8.4;

import './IERC721A.sol';

/**
 * @dev Interface of ERC721 token receiver.
 */
interface ERC721A__IERC721Receiver {
    function onERC721Received(
        address operator,
        address from,
        uint256 tokenId,
        bytes calldata data
    ) external returns (bytes4);
}

/**
 * @title ERC721A
 *
 * @dev Implementation of the [ERC721](https://eips.ethereum.org/EIPS/eip-721)
 * Non-Fungible Token Standard, including the Metadata extension.
 * Optimized for lower gas during batch mints.
 *
 * Token IDs are minted in sequential order (e.g. 0, 1, 2, 3, ...)
 * starting from `_startTokenId()`.
 *
 * Assumptions:
 *
 * - An owner cannot have more than 2**64 - 1 (max value of uint64) of supply.
 * - The maximum token ID cannot exceed 2**256 - 1 (max value of uint256).
 */
contract ERC721A is IERC721A {
    // Reference type for token approval.
    struct TokenApprovalRef {
        address value;
    }

    // =============================================================
    //                           CONSTANTS
    // =============================================================

    // Mask of an entry in packed address data.
    uint256 private constant _BITMASK_ADDRESS_DATA_ENTRY = (1 << 64) - 1;

    // The bit position of `numberMinted` in packed address data.
    uint256 private constant _BITPOS_NUMBER_MINTED = 64;

    // The bit position of `numberBurned` in packed address data.
    uint256 private constant _BITPOS_NUMBER_BURNED = 128;

    // The bit position of `aux` in packed address data.
    uint256 private constant _BITPOS_AUX = 192;

    // Mask of all 256 bits in packed address data except the 64 bits for `aux`.
    uint256 private constant _BITMASK_AUX_COMPLEMENT = (1 << 192) - 1;

    // The bit position of `startTimestamp` in packed ownership.
    uint256 private constant _BITPOS_START_TIMESTAMP = 160;

    // The bit mask of the `burned` bit in packed ownership.
    uint256 private constant _BITMASK_BURNED = 1 << 224;

    // The bit position of the `nextInitialized` bit in packed ownership.
    uint256 private constant _BITPOS_NEXT_INITIALIZED = 225;

    // The bit mask of the `nextInitialized` bit in packed ownership.
    uint256 private constant _BITMASK_NEXT_INITIALIZED = 1 << 225;

    // The bit position of `extraData` in packed ownership.
    uint256 private constant _BITPOS_EXTRA_DATA = 232;

    // Mask of all 256 bits in a packed ownership except the 24 bits for `extraData`.
    uint256 private constant _BITMASK_EXTRA_DATA_COMPLEMENT = (1 << 232) - 1;

    // The mask of the lower 160 bits for addresses.
    uint256 private constant _BITMASK_ADDRESS = (1 << 160) - 1;

    // The maximum `quantity` that can be minted with {_mintERC2309}.
    // This limit is to prevent overflows on the address data entries.
    // For a limit of 5000, a total of 3.689e15 calls to {_mintERC2309}
    // is required to cause an overflow, which is unrealistic.
    uint256 private constant _MAX_MINT_ERC2309_QUANTITY_LIMIT = 5000;

    // The `Transfer` event signature is given by:
    // `keccak256(bytes("Transfer(address,address,uint256)"))`.
    bytes32 private constant _TRANSFER_EVENT_SIGNATURE =
        0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef;

    // =============================================================
    //                            STORAGE
    // =============================================================

    // The next token ID to be minted.
    uint256 private _currentIndex;

    // The number of tokens burned.
    uint256 private _burnCounter;

    // Token name
    string private _name;

    // Token symbol
    string private _symbol;

    // Mapping from token ID to ownership details
    // An empty struct value does not necessarily mean the token is unowned.
    // See {_packedOwnershipOf} implementation for details.
    //
    // Bits Layout:
    // - [0..159]   `addr`
    // - [160..223] `startTimestamp`
    // - [224]      `burned`
    // - [225]      `nextInitialized`
    // - [232..255] `extraData`
    mapping(uint256 => uint256) private _packedOwnerships;

    // Mapping owner address to address data.
    //
    // Bits Layout:
    // - [0..63]    `balance`
    // - [64..127]  `numberMinted`
    // - [128..191] `numberBurned`
    // - [192..255] `aux`
    mapping(address => uint256) private _packedAddressData;

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

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

    // =============================================================
    //                          CONSTRUCTOR
    // =============================================================

    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
        _currentIndex = _startTokenId();
    }

    // =============================================================
    //                   TOKEN COUNTING OPERATIONS
    // =============================================================

    /**
     * @dev Returns the starting token ID.
     * To change the starting token ID, please override this function.
     */
    function _startTokenId() internal view virtual returns (uint256) {
        return 0;
    }

    /**
     * @dev Returns the next token ID to be minted.
     */
    function _nextTokenId() internal view virtual returns (uint256) {
        return _currentIndex;
    }

    /**
     * @dev Returns the total number of tokens in existence.
     * Burned tokens will reduce the count.
     * To get the total number of tokens minted, please see {_totalMinted}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        // Counter underflow is impossible as _burnCounter cannot be incremented
        // more than `_currentIndex - _startTokenId()` times.
        unchecked {
            return _currentIndex - _burnCounter - _startTokenId();
        }
    }

    /**
     * @dev Returns the total amount of tokens minted in the contract.
     */
    function _totalMinted() internal view virtual returns (uint256) {
        // Counter underflow is impossible as `_currentIndex` does not decrement,
        // and it is initialized to `_startTokenId()`.
        unchecked {
            return _currentIndex - _startTokenId();
        }
    }

    /**
     * @dev Returns the total number of tokens burned.
     */
    function _totalBurned() internal view virtual returns (uint256) {
        return _burnCounter;
    }

    // =============================================================
    //                    ADDRESS DATA OPERATIONS
    // =============================================================

    /**
     * @dev Returns the number of tokens in `owner`'s account.
     */
    function balanceOf(address owner) public view virtual override returns (uint256) {
        if (owner == address(0)) revert BalanceQueryForZeroAddress();
        return _packedAddressData[owner] & _BITMASK_ADDRESS_DATA_ENTRY;
    }

    /**
     * Returns the number of tokens minted by `owner`.
     */
    function _numberMinted(address owner) internal view returns (uint256) {
        return (_packedAddressData[owner] >> _BITPOS_NUMBER_MINTED) & _BITMASK_ADDRESS_DATA_ENTRY;
    }

    /**
     * Returns the number of tokens burned by or on behalf of `owner`.
     */
    function _numberBurned(address owner) internal view returns (uint256) {
        return (_packedAddressData[owner] >> _BITPOS_NUMBER_BURNED) & _BITMASK_ADDRESS_DATA_ENTRY;
    }

    /**
     * Returns the auxiliary data for `owner`. (e.g. number of whitelist mint slots used).
     */
    function _getAux(address owner) internal view returns (uint64) {
        return uint64(_packedAddressData[owner] >> _BITPOS_AUX);
    }

    /**
     * Sets the auxiliary data for `owner`. (e.g. number of whitelist mint slots used).
     * If there are multiple variables, please pack them into a uint64.
     */
    function _setAux(address owner, uint64 aux) internal virtual {
        uint256 packed = _packedAddressData[owner];
        uint256 auxCasted;
        // Cast `aux` with assembly to avoid redundant masking.
        assembly {
            auxCasted := aux
        }
        packed = (packed & _BITMASK_AUX_COMPLEMENT) | (auxCasted << _BITPOS_AUX);
        _packedAddressData[owner] = packed;
    }

    // =============================================================
    //                            IERC165
    // =============================================================

    /**
     * @dev Returns true if this contract implements the interface defined by
     * `interfaceId`. See the corresponding
     * [EIP section](https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified)
     * to learn more about how these ids are created.
     *
     * This function call must use less than 30000 gas.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
        // The interface IDs are constants representing the first 4 bytes
        // of the XOR of all function selectors in the interface.
        // See: [ERC165](https://eips.ethereum.org/EIPS/eip-165)
        // (e.g. `bytes4(i.functionA.selector ^ i.functionB.selector ^ ...)`)
        return
            interfaceId == 0x01ffc9a7 || // ERC165 interface ID for ERC165.
            interfaceId == 0x80ac58cd || // ERC165 interface ID for ERC721.
            interfaceId == 0x5b5e139f; // ERC165 interface ID for ERC721Metadata.
    }

    // =============================================================
    //                        IERC721Metadata
    // =============================================================

    /**
     * @dev Returns the token collection name.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the token collection symbol.
     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    /**
     * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
     */
    function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
        if (!_exists(tokenId)) revert URIQueryForNonexistentToken();

        string memory baseURI = _baseURI();
        return bytes(baseURI).length != 0 ? string(abi.encodePacked(baseURI, _toString(tokenId))) : '';
    }

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

    // =============================================================
    //                     OWNERSHIPS OPERATIONS
    // =============================================================

    /**
     * @dev Returns the owner of the `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function ownerOf(uint256 tokenId) public view virtual override returns (address) {
        return address(uint160(_packedOwnershipOf(tokenId)));
    }

    /**
     * @dev Gas spent here starts off proportional to the maximum mint batch size.
     * It gradually moves to O(1) as tokens get transferred around over time.
     */
    function _ownershipOf(uint256 tokenId) internal view virtual returns (TokenOwnership memory) {
        return _unpackedOwnership(_packedOwnershipOf(tokenId));
    }

    /**
     * @dev Returns the unpacked `TokenOwnership` struct at `index`.
     */
    function _ownershipAt(uint256 index) internal view virtual returns (TokenOwnership memory) {
        return _unpackedOwnership(_packedOwnerships[index]);
    }

    /**
     * @dev Initializes the ownership slot minted at `index` for efficiency purposes.
     */
    function _initializeOwnershipAt(uint256 index) internal virtual {
        if (_packedOwnerships[index] == 0) {
            _packedOwnerships[index] = _packedOwnershipOf(index);
        }
    }

    /**
     * Returns the packed ownership data of `tokenId`.
     */
    function _packedOwnershipOf(uint256 tokenId) private view returns (uint256) {
        uint256 curr = tokenId;

        unchecked {
            if (_startTokenId() <= curr)
                if (curr < _currentIndex) {
                    uint256 packed = _packedOwnerships[curr];
                    // If not burned.
                    if (packed & _BITMASK_BURNED == 0) {
                        // Invariant:
                        // There will always be an initialized ownership slot
                        // (i.e. `ownership.addr != address(0) && ownership.burned == false`)
                        // before an unintialized ownership slot
                        // (i.e. `ownership.addr == address(0) && ownership.burned == false`)
                        // Hence, `curr` will not underflow.
                        //
                        // We can directly compare the packed value.
                        // If the address is zero, packed will be zero.
                        while (packed == 0) {
                            packed = _packedOwnerships[--curr];
                        }
                        return packed;
                    }
                }
        }
        revert OwnerQueryForNonexistentToken();
    }

    /**
     * @dev Returns the unpacked `TokenOwnership` struct from `packed`.
     */
    function _unpackedOwnership(uint256 packed) private pure returns (TokenOwnership memory ownership) {
        ownership.addr = address(uint160(packed));
        ownership.startTimestamp = uint64(packed >> _BITPOS_START_TIMESTAMP);
        ownership.burned = packed & _BITMASK_BURNED != 0;
        ownership.extraData = uint24(packed >> _BITPOS_EXTRA_DATA);
    }

    /**
     * @dev Packs ownership data into a single uint256.
     */
    function _packOwnershipData(address owner, uint256 flags) private view returns (uint256 result) {
        assembly {
            // Mask `owner` to the lower 160 bits, in case the upper bits somehow aren't clean.
            owner := and(owner, _BITMASK_ADDRESS)
            // `owner | (block.timestamp << _BITPOS_START_TIMESTAMP) | flags`.
            result := or(owner, or(shl(_BITPOS_START_TIMESTAMP, timestamp()), flags))
        }
    }

    /**
     * @dev Returns the `nextInitialized` flag set if `quantity` equals 1.
     */
    function _nextInitializedFlag(uint256 quantity) private pure returns (uint256 result) {
        // For branchless setting of the `nextInitialized` flag.
        assembly {
            // `(quantity == 1) << _BITPOS_NEXT_INITIALIZED`.
            result := shl(_BITPOS_NEXT_INITIALIZED, eq(quantity, 1))
        }
    }

    // =============================================================
    //                      APPROVAL OPERATIONS
    // =============================================================

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

        if (_msgSenderERC721A() != owner)
            if (!isApprovedForAll(owner, _msgSenderERC721A())) {
                revert ApprovalCallerNotOwnerNorApproved();
            }

        _tokenApprovals[tokenId].value = to;
        emit Approval(owner, to, tokenId);
    }

    /**
     * @dev Returns the account approved for `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function getApproved(uint256 tokenId) public view virtual override returns (address) {
        if (!_exists(tokenId)) revert ApprovalQueryForNonexistentToken();

        return _tokenApprovals[tokenId].value;
    }

    /**
     * @dev Approve or remove `operator` as an operator for the caller.
     * Operators can call {transferFrom} or {safeTransferFrom}
     * for any token owned by the caller.
     *
     * Requirements:
     *
     * - The `operator` cannot be the caller.
     *
     * Emits an {ApprovalForAll} event.
     */
    function setApprovalForAll(address operator, bool approved) public virtual override {
        if (operator == _msgSenderERC721A()) revert ApproveToCaller();

        _operatorApprovals[_msgSenderERC721A()][operator] = approved;
        emit ApprovalForAll(_msgSenderERC721A(), operator, approved);
    }

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

    /**
     * @dev Returns whether `tokenId` exists.
     *
     * Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
     *
     * Tokens start existing when they are minted. See {_mint}.
     */
    function _exists(uint256 tokenId) internal view virtual returns (bool) {
        return
            _startTokenId() <= tokenId &&
            tokenId < _currentIndex && // If within bounds,
            _packedOwnerships[tokenId] & _BITMASK_BURNED == 0; // and not burned.
    }

    /**
     * @dev Returns whether `msgSender` is equal to `approvedAddress` or `owner`.
     */
    function _isSenderApprovedOrOwner(
        address approvedAddress,
        address owner,
        address msgSender
    ) private pure returns (bool result) {
        assembly {
            // Mask `owner` to the lower 160 bits, in case the upper bits somehow aren't clean.
            owner := and(owner, _BITMASK_ADDRESS)
            // Mask `msgSender` to the lower 160 bits, in case the upper bits somehow aren't clean.
            msgSender := and(msgSender, _BITMASK_ADDRESS)
            // `msgSender == owner || msgSender == approvedAddress`.
            result := or(eq(msgSender, owner), eq(msgSender, approvedAddress))
        }
    }

    /**
     * @dev Returns the storage slot and value for the approved address of `tokenId`.
     */
    function _getApprovedSlotAndAddress(uint256 tokenId)
        private
        view
        returns (uint256 approvedAddressSlot, address approvedAddress)
    {
        TokenApprovalRef storage tokenApproval = _tokenApprovals[tokenId];
        // The following is equivalent to `approvedAddress = _tokenApprovals[tokenId]`.
        assembly {
            approvedAddressSlot := tokenApproval.slot
            approvedAddress := sload(approvedAddressSlot)
        }
    }

    // =============================================================
    //                      TRANSFER OPERATIONS
    // =============================================================

    /**
     * @dev Transfers `tokenId` from `from` to `to`.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token
     * by either {approve} or {setApprovalForAll}.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address from,
        address to,
        uint256 tokenId
    ) public virtual override {
        uint256 prevOwnershipPacked = _packedOwnershipOf(tokenId);

        if (address(uint160(prevOwnershipPacked)) != from) revert TransferFromIncorrectOwner();

        (uint256 approvedAddressSlot, address approvedAddress) = _getApprovedSlotAndAddress(tokenId);

        // The nested ifs save around 20+ gas over a compound boolean condition.
        if (!_isSenderApprovedOrOwner(approvedAddress, from, _msgSenderERC721A()))
            if (!isApprovedForAll(from, _msgSenderERC721A())) revert TransferCallerNotOwnerNorApproved();

        if (to == address(0)) revert TransferToZeroAddress();

        _beforeTokenTransfers(from, to, tokenId, 1);

        // Clear approvals from the previous owner.
        assembly {
            if approvedAddress {
                // This is equivalent to `delete _tokenApprovals[tokenId]`.
                sstore(approvedAddressSlot, 0)
            }
        }

        // Underflow of the sender's balance is impossible because we check for
        // ownership above and the recipient's balance can't realistically overflow.
        // Counter overflow is incredibly unrealistic as `tokenId` would have to be 2**256.
        unchecked {
            // We can directly increment and decrement the balances.
            --_packedAddressData[from]; // Updates: `balance -= 1`.
            ++_packedAddressData[to]; // Updates: `balance += 1`.

            // Updates:
            // - `address` to the next owner.
            // - `startTimestamp` to the timestamp of transfering.
            // - `burned` to `false`.
            // - `nextInitialized` to `true`.
            _packedOwnerships[tokenId] = _packOwnershipData(
                to,
                _BITMASK_NEXT_INITIALIZED | _nextExtraData(from, to, prevOwnershipPacked)
            );

            // If the next slot may not have been initialized (i.e. `nextInitialized == false`) .
            if (prevOwnershipPacked & _BITMASK_NEXT_INITIALIZED == 0) {
                uint256 nextTokenId = tokenId + 1;
                // If the next slot's address is zero and not burned (i.e. packed value is zero).
                if (_packedOwnerships[nextTokenId] == 0) {
                    // If the next slot is within bounds.
                    if (nextTokenId != _currentIndex) {
                        // Initialize the next slot to maintain correctness for `ownerOf(tokenId + 1)`.
                        _packedOwnerships[nextTokenId] = prevOwnershipPacked;
                    }
                }
            }
        }

        emit Transfer(from, to, tokenId);
        _afterTokenTransfers(from, to, tokenId, 1);
    }

    /**
     * @dev Equivalent to `safeTransferFrom(from, to, tokenId, '')`.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId
    ) public virtual override {
        safeTransferFrom(from, to, tokenId, '');
    }

    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token
     * by either {approve} or {setApprovalForAll}.
     * - If `to` refers to a smart contract, it must implement
     * {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId,
        bytes memory _data
    ) public virtual override {
        transferFrom(from, to, tokenId);
        if (to.code.length != 0)
            if (!_checkContractOnERC721Received(from, to, tokenId, _data)) {
                revert TransferToNonERC721ReceiverImplementer();
            }
    }

    /**
     * @dev Hook that is called before a set of serially-ordered token IDs
     * are about to be transferred. This includes minting.
     * And also called before burning one token.
     *
     * `startTokenId` - the first token ID to be transferred.
     * `quantity` - the amount to be transferred.
     *
     * Calling conditions:
     *
     * - When `from` and `to` are both non-zero, `from`'s `tokenId` will be
     * transferred to `to`.
     * - When `from` is zero, `tokenId` will be minted for `to`.
     * - When `to` is zero, `tokenId` will be burned by `from`.
     * - `from` and `to` are never both zero.
     */
    function _beforeTokenTransfers(
        address from,
        address to,
        uint256 startTokenId,
        uint256 quantity
    ) internal virtual {}

    /**
     * @dev Hook that is called after a set of serially-ordered token IDs
     * have been transferred. This includes minting.
     * And also called after one token has been burned.
     *
     * `startTokenId` - the first token ID to be transferred.
     * `quantity` - the amount to be transferred.
     *
     * Calling conditions:
     *
     * - When `from` and `to` are both non-zero, `from`'s `tokenId` has been
     * transferred to `to`.
     * - When `from` is zero, `tokenId` has been minted for `to`.
     * - When `to` is zero, `tokenId` has been burned by `from`.
     * - `from` and `to` are never both zero.
     */
    function _afterTokenTransfers(
        address from,
        address to,
        uint256 startTokenId,
        uint256 quantity
    ) internal virtual {}

    /**
     * @dev Private function to invoke {IERC721Receiver-onERC721Received} on a target contract.
     *
     * `from` - Previous owner of the given token ID.
     * `to` - Target address that will receive the token.
     * `tokenId` - Token ID to be transferred.
     * `_data` - Optional data to send along with the call.
     *
     * Returns whether the call correctly returned the expected magic value.
     */
    function _checkContractOnERC721Received(
        address from,
        address to,
        uint256 tokenId,
        bytes memory _data
    ) private returns (bool) {
        try ERC721A__IERC721Receiver(to).onERC721Received(_msgSenderERC721A(), from, tokenId, _data) returns (
            bytes4 retval
        ) {
            return retval == ERC721A__IERC721Receiver(to).onERC721Received.selector;
        } catch (bytes memory reason) {
            if (reason.length == 0) {
                revert TransferToNonERC721ReceiverImplementer();
            } else {
                assembly {
                    revert(add(32, reason), mload(reason))
                }
            }
        }
    }

    // =============================================================
    //                        MINT OPERATIONS
    // =============================================================

    /**
     * @dev Mints `quantity` tokens and transfers them to `to`.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - `quantity` must be greater than 0.
     *
     * Emits a {Transfer} event for each mint.
     */
    function _mint(address to, uint256 quantity) internal virtual {
        uint256 startTokenId = _currentIndex;
        if (quantity == 0) revert MintZeroQuantity();

        _beforeTokenTransfers(address(0), to, startTokenId, quantity);

        // Overflows are incredibly unrealistic.
        // `balance` and `numberMinted` have a maximum limit of 2**64.
        // `tokenId` has a maximum limit of 2**256.
        unchecked {
            // Updates:
            // - `balance += quantity`.
            // - `numberMinted += quantity`.
            //
            // We can directly add to the `balance` and `numberMinted`.
            _packedAddressData[to] += quantity * ((1 << _BITPOS_NUMBER_MINTED) | 1);

            // Updates:
            // - `address` to the owner.
            // - `startTimestamp` to the timestamp of minting.
            // - `burned` to `false`.
            // - `nextInitialized` to `quantity == 1`.
            _packedOwnerships[startTokenId] = _packOwnershipData(
                to,
                _nextInitializedFlag(quantity) | _nextExtraData(address(0), to, 0)
            );

            uint256 toMasked;
            uint256 end = startTokenId + quantity;

            // Use assembly to loop and emit the `Transfer` event for gas savings.
            assembly {
                // Mask `to` to the lower 160 bits, in case the upper bits somehow aren't clean.
                toMasked := and(to, _BITMASK_ADDRESS)
                // Emit the `Transfer` event.
                log4(
                    0, // Start of data (0, since no data).
                    0, // End of data (0, since no data).
                    _TRANSFER_EVENT_SIGNATURE, // Signature.
                    0, // `address(0)`.
                    toMasked, // `to`.
                    startTokenId // `tokenId`.
                )

                for {
                    let tokenId := add(startTokenId, 1)
                } iszero(eq(tokenId, end)) {
                    tokenId := add(tokenId, 1)
                } {
                    // Emit the `Transfer` event. Similar to above.
                    log4(0, 0, _TRANSFER_EVENT_SIGNATURE, 0, toMasked, tokenId)
                }
            }
            if (toMasked == 0) revert MintToZeroAddress();

            _currentIndex = end;
        }
        _afterTokenTransfers(address(0), to, startTokenId, quantity);
    }

    /**
     * @dev Mints `quantity` tokens and transfers them to `to`.
     *
     * This function is intended for efficient minting only during contract creation.
     *
     * It emits only one {ConsecutiveTransfer} as defined in
     * [ERC2309](https://eips.ethereum.org/EIPS/eip-2309),
     * instead of a sequence of {Transfer} event(s).
     *
     * Calling this function outside of contract creation WILL make your contract
     * non-compliant with the ERC721 standard.
     * For full ERC721 compliance, substituting ERC721 {Transfer} event(s) with the ERC2309
     * {ConsecutiveTransfer} event is only permissible during contract creation.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - `quantity` must be greater than 0.
     *
     * Emits a {ConsecutiveTransfer} event.
     */
    function _mintERC2309(address to, uint256 quantity) internal virtual {
        uint256 startTokenId = _currentIndex;
        if (to == address(0)) revert MintToZeroAddress();
        if (quantity == 0) revert MintZeroQuantity();
        if (quantity > _MAX_MINT_ERC2309_QUANTITY_LIMIT) revert MintERC2309QuantityExceedsLimit();

        _beforeTokenTransfers(address(0), to, startTokenId, quantity);

        // Overflows are unrealistic due to the above check for `quantity` to be below the limit.
        unchecked {
            // Updates:
            // - `balance += quantity`.
            // - `numberMinted += quantity`.
            //
            // We can directly add to the `balance` and `numberMinted`.
            _packedAddressData[to] += quantity * ((1 << _BITPOS_NUMBER_MINTED) | 1);

            // Updates:
            // - `address` to the owner.
            // - `startTimestamp` to the timestamp of minting.
            // - `burned` to `false`.
            // - `nextInitialized` to `quantity == 1`.
            _packedOwnerships[startTokenId] = _packOwnershipData(
                to,
                _nextInitializedFlag(quantity) | _nextExtraData(address(0), to, 0)
            );

            emit ConsecutiveTransfer(startTokenId, startTokenId + quantity - 1, address(0), to);

            _currentIndex = startTokenId + quantity;
        }
        _afterTokenTransfers(address(0), to, startTokenId, quantity);
    }

    /**
     * @dev Safely mints `quantity` tokens and transfers them to `to`.
     *
     * Requirements:
     *
     * - If `to` refers to a smart contract, it must implement
     * {IERC721Receiver-onERC721Received}, which is called for each safe transfer.
     * - `quantity` must be greater than 0.
     *
     * See {_mint}.
     *
     * Emits a {Transfer} event for each mint.
     */
    function _safeMint(
        address to,
        uint256 quantity,
        bytes memory _data
    ) internal virtual {
        _mint(to, quantity);

        unchecked {
            if (to.code.length != 0) {
                uint256 end = _currentIndex;
                uint256 index = end - quantity;
                do {
                    if (!_checkContractOnERC721Received(address(0), to, index++, _data)) {
                        revert TransferToNonERC721ReceiverImplementer();
                    }
                } while (index < end);
                // Reentrancy protection.
                if (_currentIndex != end) revert();
            }
        }
    }

    /**
     * @dev Equivalent to `_safeMint(to, quantity, '')`.
     */
    function _safeMint(address to, uint256 quantity) internal virtual {
        _safeMint(to, quantity, '');
    }

    // =============================================================
    //                        BURN OPERATIONS
    // =============================================================

    /**
     * @dev Equivalent to `_burn(tokenId, false)`.
     */
    function _burn(uint256 tokenId) internal virtual {
        _burn(tokenId, false);
    }

    /**
     * @dev Destroys `tokenId`.
     * The approval is cleared when the token is burned.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     *
     * Emits a {Transfer} event.
     */
    function _burn(uint256 tokenId, bool approvalCheck) internal virtual {
        uint256 prevOwnershipPacked = _packedOwnershipOf(tokenId);

        address from = address(uint160(prevOwnershipPacked));

        (uint256 approvedAddressSlot, address approvedAddress) = _getApprovedSlotAndAddress(tokenId);

        if (approvalCheck) {
            // The nested ifs save around 20+ gas over a compound boolean condition.
            if (!_isSenderApprovedOrOwner(approvedAddress, from, _msgSenderERC721A()))
                if (!isApprovedForAll(from, _msgSenderERC721A())) revert TransferCallerNotOwnerNorApproved();
        }

        _beforeTokenTransfers(from, address(0), tokenId, 1);

        // Clear approvals from the previous owner.
        assembly {
            if approvedAddress {
                // This is equivalent to `delete _tokenApprovals[tokenId]`.
                sstore(approvedAddressSlot, 0)
            }
        }

        // Underflow of the sender's balance is impossible because we check for
        // ownership above and the recipient's balance can't realistically overflow.
        // Counter overflow is incredibly unrealistic as `tokenId` would have to be 2**256.
        unchecked {
            // Updates:
            // - `balance -= 1`.
            // - `numberBurned += 1`.
            //
            // We can directly decrement the balance, and increment the number burned.
            // This is equivalent to `packed -= 1; packed += 1 << _BITPOS_NUMBER_BURNED;`.
            _packedAddressData[from] += (1 << _BITPOS_NUMBER_BURNED) - 1;

            // Updates:
            // - `address` to the last owner.
            // - `startTimestamp` to the timestamp of burning.
            // - `burned` to `true`.
            // - `nextInitialized` to `true`.
            _packedOwnerships[tokenId] = _packOwnershipData(
                from,
                (_BITMASK_BURNED | _BITMASK_NEXT_INITIALIZED) | _nextExtraData(from, address(0), prevOwnershipPacked)
            );

            // If the next slot may not have been initialized (i.e. `nextInitialized == false`) .
            if (prevOwnershipPacked & _BITMASK_NEXT_INITIALIZED == 0) {
                uint256 nextTokenId = tokenId + 1;
                // If the next slot's address is zero and not burned (i.e. packed value is zero).
                if (_packedOwnerships[nextTokenId] == 0) {
                    // If the next slot is within bounds.
                    if (nextTokenId != _currentIndex) {
                        // Initialize the next slot to maintain correctness for `ownerOf(tokenId + 1)`.
                        _packedOwnerships[nextTokenId] = prevOwnershipPacked;
                    }
                }
            }
        }

        emit Transfer(from, address(0), tokenId);
        _afterTokenTransfers(from, address(0), tokenId, 1);

        // Overflow not possible, as _burnCounter cannot be exceed _currentIndex times.
        unchecked {
            _burnCounter++;
        }
    }

    // =============================================================
    //                     EXTRA DATA OPERATIONS
    // =============================================================

    /**
     * @dev Directly sets the extra data for the ownership data `index`.
     */
    function _setExtraDataAt(uint256 index, uint24 extraData) internal virtual {
        uint256 packed = _packedOwnerships[index];
        if (packed == 0) revert OwnershipNotInitializedForExtraData();
        uint256 extraDataCasted;
        // Cast `extraData` with assembly to avoid redundant masking.
        assembly {
            extraDataCasted := extraData
        }
        packed = (packed & _BITMASK_EXTRA_DATA_COMPLEMENT) | (extraDataCasted << _BITPOS_EXTRA_DATA);
        _packedOwnerships[index] = packed;
    }

    /**
     * @dev Called during each token transfer to set the 24bit `extraData` field.
     * Intended to be overridden by the cosumer contract.
     *
     * `previousExtraData` - the value of `extraData` before transfer.
     *
     * Calling conditions:
     *
     * - When `from` and `to` are both non-zero, `from`'s `tokenId` will be
     * transferred to `to`.
     * - When `from` is zero, `tokenId` will be minted for `to`.
     * - When `to` is zero, `tokenId` will be burned by `from`.
     * - `from` and `to` are never both zero.
     */
    function _extraData(
        address from,
        address to,
        uint24 previousExtraData
    ) internal view virtual returns (uint24) {}

    /**
     * @dev Returns the next extra data for the packed ownership data.
     * The returned result is shifted into position.
     */
    function _nextExtraData(
        address from,
        address to,
        uint256 prevOwnershipPacked
    ) private view returns (uint256) {
        uint24 extraData = uint24(prevOwnershipPacked >> _BITPOS_EXTRA_DATA);
        return uint256(_extraData(from, to, extraData)) << _BITPOS_EXTRA_DATA;
    }

    // =============================================================
    //                       OTHER OPERATIONS
    // =============================================================

    /**
     * @dev Returns the message sender (defaults to `msg.sender`).
     *
     * If you are writing GSN compatible contracts, you need to override this function.
     */
    function _msgSenderERC721A() internal view virtual returns (address) {
        return msg.sender;
    }

    /**
     * @dev Converts a uint256 to its ASCII string decimal representation.
     */
    function _toString(uint256 value) internal pure virtual returns (string memory str) {
        assembly {
            // The maximum value of a uint256 contains 78 digits (1 byte per digit),
            // but we allocate 0x80 bytes to keep the free memory pointer 32-byte word aliged.
            // We will need 1 32-byte word to store the length,
            // and 3 32-byte words to store a maximum of 78 digits. Total: 0x20 + 3 * 0x20 = 0x80.
            str := add(mload(0x40), 0x80)
            // Update the free memory pointer to allocate.
            mstore(0x40, str)

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

            // We write the string from rightmost digit to leftmost digit.
            // The following is essentially a do-while loop that also handles the zero case.
            // prettier-ignore
            for { let temp := value } 1 {} {
                str := 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)
                // prettier-ignore
                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)
        }
    }
}

// File: contracts/interfaces/IShufflerToken.sol



// SPDX-License-Identifier: GPL-3.0

/// @title Interface for ShufflerToken

/**************************************************************************
...........................................................................
...........................................................................
...........................................................................
...........................................................................
.....................     ...............      .......      ...............
...................  .?5?:  ........... .::::::. ... .:::::.  .............
.................  :?B&@&B?:  ....... .^7??????!:. .~7??????~: ............
...............  :J#&&&&&&&#J:  .....^7??????JJJ?!!7????JJJ?J?!............
.............  ^Y#&&&&&&&&&&&#Y^  .. !J??YGGP^^~?JJ?5GGJ^^~????: ..........
...........  ^5&@&&&&&&&&&&&&&@&5~   !J??5@@B. .7???G@@Y  :????:...........
.......... :5&&BBB###&&&&#BBB###&&P: ~???5@@B. .7???G@@Y  :???7............
......... ^P&&#:..7J?G&&&5..:??J#&&G~ ~??J55Y!!!????Y5PJ!!!??7.............
......... !@&&#.  7??G&&&5  :??J#&&@7  ^?????JJJ????????JJJ?7..............
......... !@&&#~^^JYJB&&&P^^~JYY#&&@7 ..:~?J??????????????7^...............
......... :JB&&&&&&&&B#&#B&&&&&&&&#J: ..  .~?J????????J?!:. ...............
..........  :?BBBBBB5YB&BY5BBBBBB?:  .....  .~77???J?7!:. .................
............  ....^Y#@@&@@#Y^....  .......... ..^!7~:.. ...................
..............   .!777???777!.   ............   :^^^.   ...................
..................  .^7?7^.  .............. .~Y5#&&&G57: ..................
................  :~???????~:  .............!&&&&&&&&@@5:..................
.............. .:!?J???????J?!:  ......... ~&&&&&&&&&&&@5 .................
............ .:!??JJJ????????J?!:. ......  ^B&&&&&&&&&&&J  ................
............^!JGBG!^^7???YBBP^^~?!^. .   .^^~YG&&&&&&#57^^:   .............
......... :7??J&&&^  !???5@@B. .?J?7: :?5G&&&#PY#&&&P5B&&&#5Y^ ............
...........~7?J&&&^  !???5@@B. .?J?~.:Y&@G77?555#&&&Y!7J55P&&#~............
........... .^75557!!7???J55Y!!!7~.  Y@&&5  .???#&&&7  ^??Y&&&&: ..........
............. .^7?JJ?????????J7^. .. J&&&5  .??J#&&&7  ^??Y&&&G: ..........
............... .^7?J???????7^. ..... ?#@#55PBG5#&&&5J5PBBB&&P: ...........
................. .:!?JJJ?!:. ........ ^!JBBBGYP&&&&B5PBBBP!!. ............
................... .:!7!:. ...........   ..:JGBGGGGBG5~ ..   .............
..................... ... ................. ............ ..................
...........................................................................
...........................................................................
...........................................................................
...........................................................................
***************************************************************************/

pragma solidity ^0.8.6;

import { IShufflerDescriptor } from './IShufflerDescriptor.sol';

interface IShufflerToken {
    event ShufflerCreated(address indexed creator, uint256 indexed startTokenId, uint256 indexed endTokenId);
    
    event NftOverridden(uint256 indexed tokenId, address indexed override_contract, uint256 indexed override_token_id);

    event DescriptorUpdated(IShufflerDescriptor descriptor);

    event DescriptorLocked();

    event SeedsLocked();

    event SeedsAdded(uint256[] seeds);

    event Reveal(uint64 offset);

    struct Seed {
        uint48 background;
        uint48 card;
        uint48 side;
        uint48 corner;
        uint48 center;
        address override_contract;
        uint64 override_token_id;
    }

    function setTreasury(address payable _treasury) external;

    function lockSeeds() external;

    function areSeedsLocked() external returns (bool);

    function addManySeeds(uint256[] calldata seeds) external;

    function seedCount() external view returns (uint256);

    function mint(uint256 count) external payable;

    function ownerMint(address to, uint256 count) external;

    function mintWhiteList(uint256 count, uint256 maxCount, bytes32[] calldata merkleProof) external payable;

    function reveal() external;

    function setDescriptor(IShufflerDescriptor descriptor) external;

    function lockDescriptor() external;

    function withdraw() external;

    function setComposePrice(uint256 _price) external;

    function setOverrideNft(uint256 tokenId, address override_contract, uint64 override_token_id) external payable;

    function removeOverrideNft(uint256 tokenId) external;
}

// File: @openzeppelin/contracts/security/ReentrancyGuard.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)

pragma solidity ^0.8.0;

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

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

    uint256 private _status;

    constructor() {
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and making it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

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

        _;

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

// File: @openzeppelin/contracts/utils/cryptography/MerkleProof.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/cryptography/MerkleProof.sol)

pragma solidity ^0.8.0;

/**
 * @dev These functions deal with verification of Merkle Tree proofs.
 *
 * The proofs can be generated using the JavaScript library
 * https://github.com/miguelmota/merkletreejs[merkletreejs].
 * Note: the hashing algorithm should be keccak256 and pair sorting should be enabled.
 *
 * See `test/utils/cryptography/MerkleProof.test.js` for some examples.
 *
 * WARNING: You should avoid using leaf values that are 64 bytes long prior to
 * hashing, or use a hash function other than keccak256 for hashing leaves.
 * This is because the concatenation of a sorted pair of internal nodes in
 * the merkle tree could be reinterpreted as a leaf value.
 */
library MerkleProof {
    /**
     * @dev Returns true if a `leaf` can be proved to be a part of a Merkle tree
     * defined by `root`. For this, a `proof` must be provided, containing
     * sibling hashes on the branch from the leaf to the root of the tree. Each
     * pair of leaves and each pair of pre-images are assumed to be sorted.
     */
    function verify(
        bytes32[] memory proof,
        bytes32 root,
        bytes32 leaf
    ) internal pure returns (bool) {
        return processProof(proof, leaf) == root;
    }

    /**
     * @dev Calldata version of {verify}
     *
     * _Available since v4.7._
     */
    function verifyCalldata(
        bytes32[] calldata proof,
        bytes32 root,
        bytes32 leaf
    ) internal pure returns (bool) {
        return processProofCalldata(proof, leaf) == root;
    }

    /**
     * @dev Returns the rebuilt hash obtained by traversing a Merkle tree up
     * from `leaf` using `proof`. A `proof` is valid if and only if the rebuilt
     * hash matches the root of the tree. When processing the proof, the pairs
     * of leafs & pre-images are assumed to be sorted.
     *
     * _Available since v4.4._
     */
    function processProof(bytes32[] memory proof, bytes32 leaf) internal pure returns (bytes32) {
        bytes32 computedHash = leaf;
        for (uint256 i = 0; i < proof.length; i++) {
            computedHash = _hashPair(computedHash, proof[i]);
        }
        return computedHash;
    }

    /**
     * @dev Calldata version of {processProof}
     *
     * _Available since v4.7._
     */
    function processProofCalldata(bytes32[] calldata proof, bytes32 leaf) internal pure returns (bytes32) {
        bytes32 computedHash = leaf;
        for (uint256 i = 0; i < proof.length; i++) {
            computedHash = _hashPair(computedHash, proof[i]);
        }
        return computedHash;
    }

    /**
     * @dev Returns true if the `leaves` can be proved to be a part of a Merkle tree defined by
     * `root`, according to `proof` and `proofFlags` as described in {processMultiProof}.
     *
     * _Available since v4.7._
     */
    function multiProofVerify(
        bytes32[] memory proof,
        bool[] memory proofFlags,
        bytes32 root,
        bytes32[] memory leaves
    ) internal pure returns (bool) {
        return processMultiProof(proof, proofFlags, leaves) == root;
    }

    /**
     * @dev Calldata version of {multiProofVerify}
     *
     * _Available since v4.7._
     */
    function multiProofVerifyCalldata(
        bytes32[] calldata proof,
        bool[] calldata proofFlags,
        bytes32 root,
        bytes32[] memory leaves
    ) internal pure returns (bool) {
        return processMultiProofCalldata(proof, proofFlags, leaves) == root;
    }

    /**
     * @dev Returns the root of a tree reconstructed from `leaves` and the sibling nodes in `proof`,
     * consuming from one or the other at each step according to the instructions given by
     * `proofFlags`.
     *
     * _Available since v4.7._
     */
    function processMultiProof(
        bytes32[] memory proof,
        bool[] memory proofFlags,
        bytes32[] memory leaves
    ) internal pure returns (bytes32 merkleRoot) {
        // This function rebuild the root hash by traversing the tree up from the leaves. The root is rebuilt by
        // consuming and producing values on a queue. The queue starts with the `leaves` array, then goes onto the
        // `hashes` array. At the end of the process, the last hash in the `hashes` array should contain the root of
        // the merkle tree.
        uint256 leavesLen = leaves.length;
        uint256 totalHashes = proofFlags.length;

        // Check proof validity.
        require(leavesLen + proof.length - 1 == totalHashes, "MerkleProof: invalid multiproof");

        // The xxxPos values are "pointers" to the next value to consume in each array. All accesses are done using
        // `xxx[xxxPos++]`, which return the current value and increment the pointer, thus mimicking a queue's "pop".
        bytes32[] memory hashes = new bytes32[](totalHashes);
        uint256 leafPos = 0;
        uint256 hashPos = 0;
        uint256 proofPos = 0;
        // At each step, we compute the next hash using two values:
        // - a value from the "main queue". If not all leaves have been consumed, we get the next leaf, otherwise we
        //   get the next hash.
        // - depending on the flag, either another value for the "main queue" (merging branches) or an element from the
        //   `proof` array.
        for (uint256 i = 0; i < totalHashes; i++) {
            bytes32 a = leafPos < leavesLen ? leaves[leafPos++] : hashes[hashPos++];
            bytes32 b = proofFlags[i] ? leafPos < leavesLen ? leaves[leafPos++] : hashes[hashPos++] : proof[proofPos++];
            hashes[i] = _hashPair(a, b);
        }

        if (totalHashes > 0) {
            return hashes[totalHashes - 1];
        } else if (leavesLen > 0) {
            return leaves[0];
        } else {
            return proof[0];
        }
    }

    /**
     * @dev Calldata version of {processMultiProof}
     *
     * _Available since v4.7._
     */
    function processMultiProofCalldata(
        bytes32[] calldata proof,
        bool[] calldata proofFlags,
        bytes32[] memory leaves
    ) internal pure returns (bytes32 merkleRoot) {
        // This function rebuild the root hash by traversing the tree up from the leaves. The root is rebuilt by
        // consuming and producing values on a queue. The queue starts with the `leaves` array, then goes onto the
        // `hashes` array. At the end of the process, the last hash in the `hashes` array should contain the root of
        // the merkle tree.
        uint256 leavesLen = leaves.length;
        uint256 totalHashes = proofFlags.length;

        // Check proof validity.
        require(leavesLen + proof.length - 1 == totalHashes, "MerkleProof: invalid multiproof");

        // The xxxPos values are "pointers" to the next value to consume in each array. All accesses are done using
        // `xxx[xxxPos++]`, which return the current value and increment the pointer, thus mimicking a queue's "pop".
        bytes32[] memory hashes = new bytes32[](totalHashes);
        uint256 leafPos = 0;
        uint256 hashPos = 0;
        uint256 proofPos = 0;
        // At each step, we compute the next hash using two values:
        // - a value from the "main queue". If not all leaves have been consumed, we get the next leaf, otherwise we
        //   get the next hash.
        // - depending on the flag, either another value for the "main queue" (merging branches) or an element from the
        //   `proof` array.
        for (uint256 i = 0; i < totalHashes; i++) {
            bytes32 a = leafPos < leavesLen ? leaves[leafPos++] : hashes[hashPos++];
            bytes32 b = proofFlags[i] ? leafPos < leavesLen ? leaves[leafPos++] : hashes[hashPos++] : proof[proofPos++];
            hashes[i] = _hashPair(a, b);
        }

        if (totalHashes > 0) {
            return hashes[totalHashes - 1];
        } else if (leavesLen > 0) {
            return leaves[0];
        } else {
            return proof[0];
        }
    }

    function _hashPair(bytes32 a, bytes32 b) private pure returns (bytes32) {
        return a < b ? _efficientHash(a, b) : _efficientHash(b, a);
    }

    function _efficientHash(bytes32 a, bytes32 b) private pure returns (bytes32 value) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, a)
            mstore(0x20, b)
            value := keccak256(0x00, 0x40)
        }
    }
}

// File: @openzeppelin/contracts/utils/Strings.sol



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

pragma solidity ^0.8.0;

/**
 * @dev String operations.
 */
library Strings {
    bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
    uint8 private constant _ADDRESS_LENGTH = 20;

    /**
     * @dev Converts a `uint256` to its ASCII `string` decimal representation.
     */
    function toString(uint256 value) internal pure returns (string memory) {
        // Inspired by OraclizeAPI's implementation - MIT licence
        // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol

        if (value == 0) {
            return "0";
        }
        uint256 temp = value;
        uint256 digits;
        while (temp != 0) {
            digits++;
            temp /= 10;
        }
        bytes memory buffer = new bytes(digits);
        while (value != 0) {
            digits -= 1;
            buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
            value /= 10;
        }
        return string(buffer);
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        if (value == 0) {
            return "0x00";
        }
        uint256 temp = value;
        uint256 length = 0;
        while (temp != 0) {
            length++;
            temp >>= 8;
        }
        return toHexString(value, length);
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
     */
    function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
        bytes memory buffer = new bytes(2 * length + 2);
        buffer[0] = "0";
        buffer[1] = "x";
        for (uint256 i = 2 * length + 1; i > 1; --i) {
            buffer[i] = _HEX_SYMBOLS[value & 0xf];
            value >>= 4;
        }
        require(value == 0, "Strings: hex length insufficient");
        return string(buffer);
    }

    /**
     * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
     */
    function toHexString(address addr) internal pure returns (string memory) {
        return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
    }
}

// File: contracts/interfaces/IShufflerDescriptor.sol



// SPDX-License-Identifier: GPL-3.0

/// @title Interface for ShufflerDescriptor

/**************************************************************************
...........................................................................
...........................................................................
...........................................................................
...........................................................................
.....................     ...............      .......      ...............
...................  .?5?:  ........... .::::::. ... .:::::.  .............
.................  :?B&@&B?:  ....... .^7??????!:. .~7??????~: ............
...............  :J#&&&&&&&#J:  .....^7??????JJJ?!!7????JJJ?J?!............
.............  ^Y#&&&&&&&&&&&#Y^  .. !J??YGGP^^~?JJ?5GGJ^^~????: ..........
...........  ^5&@&&&&&&&&&&&&&@&5~   !J??5@@B. .7???G@@Y  :????:...........
.......... :5&&BBB###&&&&#BBB###&&P: ~???5@@B. .7???G@@Y  :???7............
......... ^P&&#:..7J?G&&&5..:??J#&&G~ ~??J55Y!!!????Y5PJ!!!??7.............
......... !@&&#.  7??G&&&5  :??J#&&@7  ^?????JJJ????????JJJ?7..............
......... !@&&#~^^JYJB&&&P^^~JYY#&&@7 ..:~?J??????????????7^...............
......... :JB&&&&&&&&B#&#B&&&&&&&&#J: ..  .~?J????????J?!:. ...............
..........  :?BBBBBB5YB&BY5BBBBBB?:  .....  .~77???J?7!:. .................
............  ....^Y#@@&@@#Y^....  .......... ..^!7~:.. ...................
..............   .!777???777!.   ............   :^^^.   ...................
..................  .^7?7^.  .............. .~Y5#&&&G57: ..................
................  :~???????~:  .............!&&&&&&&&@@5:..................
.............. .:!?J???????J?!:  ......... ~&&&&&&&&&&&@5 .................
............ .:!??JJJ????????J?!:. ......  ^B&&&&&&&&&&&J  ................
............^!JGBG!^^7???YBBP^^~?!^. .   .^^~YG&&&&&&#57^^:   .............
......... :7??J&&&^  !???5@@B. .?J?7: :?5G&&&#PY#&&&P5B&&&#5Y^ ............
...........~7?J&&&^  !???5@@B. .?J?~.:Y&@G77?555#&&&Y!7J55P&&#~............
........... .^75557!!7???J55Y!!!7~.  Y@&&5  .???#&&&7  ^??Y&&&&: ..........
............. .^7?JJ?????????J7^. .. J&&&5  .??J#&&&7  ^??Y&&&G: ..........
............... .^7?J???????7^. ..... ?#@#55PBG5#&&&5J5PBBB&&P: ...........
................. .:!?JJJ?!:. ........ ^!JBBBGYP&&&&B5PBBBP!!. ............
................... .:!7!:. ...........   ..:JGBGGGGBG5~ ..   .............
..................... ... ................. ............ ..................
...........................................................................
...........................................................................
...........................................................................
...........................................................................
***************************************************************************/

pragma solidity ^0.8.6;

import { IShufflerToken } from './IShufflerToken.sol';

interface IShufflerDescriptor {
    event PartsLocked();

    event DataURIToggled(bool enabled);

    event BaseURIUpdated(string baseURI);

    function arePartsLocked() external returns (bool);

    function isDataURIEnabled() external returns (bool);

    function baseURI() external view returns (string memory);

    function palettes(uint8 paletteIndex, uint256 colorIndex) external view returns (string memory);

    function backgrounds(uint256 index) external view returns (string memory);

    function cards(uint256 index) external view returns (bytes memory);

    function sides(uint256 index) external view returns (bytes memory);

    function corners(uint256 index) external view returns (bytes memory);

    function centers(uint256 index) external view returns (bytes memory);

    function backgroundCount() external view returns (uint256);

    function cardCount() external view returns (uint256);

    function sideCount() external view returns (uint256);

    function cornerCount() external view returns (uint256);

    function centerCount() external view returns (uint256);

    function addManyColorsToPalette(uint8 paletteIndex, string[] calldata newColors) external;

    function addManyBackgrounds(string[] calldata backgrounds) external;

    function addManyCards(bytes[] calldata cards) external;

    function addManySides(bytes[] calldata sides) external;

    function addManyCorners(bytes[] calldata corners) external;

    function addManyCenters(bytes[] calldata centers) external;

    function addColorToPalette(uint8 paletteIndex, string calldata color) external;

    function addBackground(string calldata background) external;

    function addSide(bytes calldata side) external;

    function addCorner(bytes calldata corner) external;

    function addCenter(bytes calldata center) external;

    function lockParts() external;

    function toggleDataURIEnabled() external;

    function setBaseURI(string calldata baseURI) external;

    function tokenURI(uint256 tokenId, IShufflerToken.Seed memory seed) external view returns (string memory);

    function dataURI(uint256 tokenId, IShufflerToken.Seed memory seed) external view returns (string memory);

    function genericDataURI(
        string calldata name,
        string calldata description,
        IShufflerToken.Seed memory seed
    ) external view returns (string memory);

    function generateSVGImage(IShufflerToken.Seed memory seed) external view returns (string memory);

    function isComposable(address addr) external view returns (bool);
}

// File: contracts/libs/base64.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0;

/**************************************************************************
...........................................................................
...........................................................................
...........................................................................
...........................................................................
.....................     ...............      .......      ...............
...................  .?5?:  ........... .::::::. ... .:::::.  .............
.................  :?B&@&B?:  ....... .^7??????!:. .~7??????~: ............
...............  :J#&&&&&&&#J:  .....^7??????JJJ?!!7????JJJ?J?!............
.............  ^Y#&&&&&&&&&&&#Y^  .. !J??YGGP^^~?JJ?5GGJ^^~????: ..........
...........  ^5&@&&&&&&&&&&&&&@&5~   !J??5@@B. .7???G@@Y  :????:...........
.......... :5&&BBB###&&&&#BBB###&&P: ~???5@@B. .7???G@@Y  :???7............
......... ^P&&#:..7J?G&&&5..:??J#&&G~ ~??J55Y!!!????Y5PJ!!!??7.............
......... !@&&#.  7??G&&&5  :??J#&&@7  ^?????JJJ????????JJJ?7..............
......... !@&&#~^^JYJB&&&P^^~JYY#&&@7 ..:~?J??????????????7^...............
......... :JB&&&&&&&&B#&#B&&&&&&&&#J: ..  .~?J????????J?!:. ...............
..........  :?BBBBBB5YB&BY5BBBBBB?:  .....  .~77???J?7!:. .................
............  ....^Y#@@&@@#Y^....  .......... ..^!7~:.. ...................
..............   .!777???777!.   ............   :^^^.   ...................
..................  .^7?7^.  .............. .~Y5#&&&G57: ..................
................  :~???????~:  .............!&&&&&&&&@@5:..................
.............. .:!?J???????J?!:  ......... ~&&&&&&&&&&&@5 .................
............ .:!??JJJ????????J?!:. ......  ^B&&&&&&&&&&&J  ................
............^!JGBG!^^7???YBBP^^~?!^. .   .^^~YG&&&&&&#57^^:   .............
......... :7??J&&&^  !???5@@B. .?J?7: :?5G&&&#PY#&&&P5B&&&#5Y^ ............
...........~7?J&&&^  !???5@@B. .?J?~.:Y&@G77?555#&&&Y!7J55P&&#~............
........... .^75557!!7???J55Y!!!7~.  Y@&&5  .???#&&&7  ^??Y&&&&: ..........
............. .^7?JJ?????????J7^. .. J&&&5  .??J#&&&7  ^??Y&&&G: ..........
............... .^7?J???????7^. ..... ?#@#55PBG5#&&&5J5PBBB&&P: ...........
................. .:!?JJJ?!:. ........ ^!JBBBGYP&&&&B5PBBBP!!. ............
................... .:!7!:. ...........   ..:JGBGGGGBG5~ ..   .............
..................... ... ................. ............ ..................
...........................................................................
...........................................................................
...........................................................................
...........................................................................
***************************************************************************/

/// @title Base64
/// @author Brecht Devos - <brecht@loopring.org>
/// @notice Provides functions for encoding/decoding base64
library Base64 {
    string internal constant TABLE_ENCODE = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';
    bytes  internal constant TABLE_DECODE = hex"0000000000000000000000000000000000000000000000000000000000000000"
                                            hex"00000000000000000000003e0000003f3435363738393a3b3c3d000000000000"
                                            hex"00000102030405060708090a0b0c0d0e0f101112131415161718190000000000"
                                            hex"001a1b1c1d1e1f202122232425262728292a2b2c2d2e2f303132330000000000";

    function encode(bytes memory data) internal pure returns (string memory) {
        if (data.length == 0) return '';

        // load the table into memory
        string memory table = TABLE_ENCODE;

        // multiply by 4/3 rounded up
        uint256 encodedLen = 4 * ((data.length + 2) / 3);

        // add some extra buffer at the end required for the writing
        string memory result = new string(encodedLen + 32);

        assembly {
            // set the actual output length
            mstore(result, encodedLen)

            // prepare the lookup table
            let tablePtr := add(table, 1)

            // input ptr
            let dataPtr := data
            let endPtr := add(dataPtr, mload(data))

            // result ptr, jump over length
            let resultPtr := add(result, 32)

            // run over the input, 3 bytes at a time
            for {} lt(dataPtr, endPtr) {}
            {
                // read 3 bytes
                dataPtr := add(dataPtr, 3)
                let input := mload(dataPtr)

                // write 4 characters
                mstore8(resultPtr, mload(add(tablePtr, and(shr(18, input), 0x3F))))
                resultPtr := add(resultPtr, 1)
                mstore8(resultPtr, mload(add(tablePtr, and(shr(12, input), 0x3F))))
                resultPtr := add(resultPtr, 1)
                mstore8(resultPtr, mload(add(tablePtr, and(shr( 6, input), 0x3F))))
                resultPtr := add(resultPtr, 1)
                mstore8(resultPtr, mload(add(tablePtr, and(        input,  0x3F))))
                resultPtr := add(resultPtr, 1)
            }

            // padding with '='
            switch mod(mload(data), 3)
            case 1 { mstore(sub(resultPtr, 2), shl(240, 0x3d3d)) }
            case 2 { mstore(sub(resultPtr, 1), shl(248, 0x3d)) }
        }

        return result;
    }

    function decode(string memory _data) internal pure returns (bytes memory) {
        bytes memory data = bytes(_data);

        if (data.length == 0) return new bytes(0);
        require(data.length % 4 == 0, "invalid base64 decoder input");

        // load the table into memory
        bytes memory table = TABLE_DECODE;

        // every 4 characters represent 3 bytes
        uint256 decodedLen = (data.length / 4) * 3;

        // add some extra buffer at the end required for the writing
        bytes memory result = new bytes(decodedLen + 32);

        assembly {
            // padding with '='
            let lastBytes := mload(add(data, mload(data)))
            if eq(and(lastBytes, 0xFF), 0x3d) {
                decodedLen := sub(decodedLen, 1)
                if eq(and(lastBytes, 0xFFFF), 0x3d3d) {
                    decodedLen := sub(decodedLen, 1)
                }
            }

            // set the actual output length
            mstore(result, decodedLen)

            // prepare the lookup table
            let tablePtr := add(table, 1)

            // input ptr
            let dataPtr := data
            let endPtr := add(dataPtr, mload(data))

            // result ptr, jump over length
            let resultPtr := add(result, 32)

            // run over the input, 4 characters at a time
            for {} lt(dataPtr, endPtr) {}
            {
               // read 4 characters
               dataPtr := add(dataPtr, 4)
               let input := mload(dataPtr)

               // write 3 bytes
               let output := add(
                   add(
                       shl(18, and(mload(add(tablePtr, and(shr(24, input), 0xFF))), 0xFF)),
                       shl(12, and(mload(add(tablePtr, and(shr(16, input), 0xFF))), 0xFF))),
                   add(
                       shl( 6, and(mload(add(tablePtr, and(shr( 8, input), 0xFF))), 0xFF)),
                               and(mload(add(tablePtr, and(        input , 0xFF))), 0xFF)
                    )
                )
                mstore(resultPtr, shl(232, output))
                resultPtr := add(resultPtr, 3)
            }
        }

        return result;
    }

    // @author onchain shufflers
    // optimized decoder for Chainrunners, one pass base64 decode and json string retrieval
    // return "image_data" field and insert "svg:nth-child(2) " in <style>
    // input: base64 encoded json with format
    // {"name":"Runner #0", "description":"Chain Runners", "image_data": "<begin><style></style></end>"}
    // output: base64 string from the "image_data" field, i.e. "<begin><style>svg:nth-child(2) </style></end>"
    function decodeChainRunnerBase64(string memory _data) internal pure returns (bytes memory) {
        bytes memory data = bytes(_data);

        if (data.length == 0) return new bytes(0);
        require(data.length % 4 == 0, "invalid base64 decoder input");

        // load the table into memory
        bytes memory table = TABLE_DECODE;

        // add some extra buffer at the end required for the writing
        bytes memory result = new bytes((data.length / 4) * 3 + 32);

        assembly {
            // prepare the lookup table
            let tablePtr := add(table, 1)

            // input ptr
            let dataPtr := data
            let endPtr := add(dataPtr, mload(data))

            // result ptr, jump over length
            let resultPtr := add(result, 32)

            let state := 0 // FSM state
            let resultLen := 0
            // run over the input, 4 characters at a time
            for {} lt(dataPtr, endPtr) {}
            {
                // read 4 characters
                dataPtr := add(dataPtr, 4)
                let input := mload(dataPtr)

                // write 3 bytes
                let output := add(
                    add(
                        shl(18, and(mload(add(tablePtr, and(shr(24, input), 0xFF))), 0xFF)),
                        shl(12, and(mload(add(tablePtr, and(shr(16, input), 0xFF))), 0xFF))
                    ),
                    add(
                        shl(6, and(mload(add(tablePtr, and(shr(8, input), 0xFF))), 0xFF)),
                        and(mload(add(tablePtr, and(input, 0xFF))), 0xFF)
                    )
                )
                let threeChar := shl(232, output)

                for {let i := 0} lt(i, 3) {i := add(i, 1)} {
                    let b := byte(i, threeChar)

                    switch state
                    // "
                    case 0 {switch eq(and(b, 0xFF), 0x22) case 1 {state := add(state, 1)}}
                    // i
                    case 1 {switch eq(and(b, 0xFF), 0x69) case 1 {state := add(state, 1)} case 0 {state := 0}}
                    // m
                    case 2 {switch eq(and(b, 0xFF), 0x6d) case 1 {state := add(state, 1)} case 0 {state := 0}}
                    // a
                    case 3 {switch eq(and(b, 0xFF), 0x61) case 1 {state := add(state, 1)} case 0 {state := 0}}
                    // g
                    case 4 {switch eq(and(b, 0xFF), 0x67) case 1 {state := add(state, 1)} case 0 {state := 0}}
                    // e
                    case 5 {switch eq(and(b, 0xFF), 0x65) case 1 {state := add(state, 1)} case 0 {state := 0}}
                    // _
                    case 6 {switch eq(and(b, 0xFF), 0x5f) case 1 {state := add(state, 1)} case 0 {state := 0}}
                    // d
                    case 7 {switch eq(and(b, 0xFF), 0x64) case 1 {state := add(state, 1)} case 0 {state := 0}}
                    // a
                    case 8 {switch eq(and(b, 0xFF), 0x61) case 1 {state := add(state, 1)} case 0 {state := 0}}
                    // t
                    case 9 {switch eq(and(b, 0xFF), 0x74) case 1 {state := add(state, 1)} case 0 {state := 0}}
                    // a
                    case 10 {switch eq(and(b, 0xFF), 0x61) case 1 {state := add(state, 1)} case 0 {state := 0}}
                    // "
                    case 11 {switch eq(and(b, 0xFF), 0x22) case 1 {state := add(state, 1)} case 0 {state := 0}}
                    // until "
                    case 12 {switch eq(and(b, 0xFF), 0x22) case 1 {state := add(state, 1)} case 0 {}}
                    // store char string until <style>
                    case 13 {
                        switch eq(and(b, 0xFF), 0x3c) case 1 {state := add(state, 1)} case 0 {}
                        mstore(resultPtr, shl(248, b)) resultPtr := add(resultPtr, 1) resultLen := add(resultLen, 1)
                    }
                    // s
                    case 14 {mstore(resultPtr, shl(248, b)) resultPtr := add(resultPtr, 1) resultLen := add(resultLen, 1)
                        switch eq(and(b, 0xFF), 0x73) case 1 {state := add(state, 1)} case 0 {state := 13}}
                    // t
                    case 15 {mstore(resultPtr, shl(248, b)) resultPtr := add(resultPtr, 1) resultLen := add(resultLen, 1)
                        switch eq(and(b, 0xFF), 0x74) case 1 {state := add(state, 1)} case 0 {state := 13}}
                    // y
                    case 16 {mstore(resultPtr, shl(248, b)) resultPtr := add(resultPtr, 1) resultLen := add(resultLen, 1)
                        switch eq(and(b, 0xFF), 0x79) case 1 {state := add(state, 1)} case 0 {state := 13}}
                    // l
                    case 17 {mstore(resultPtr, shl(248, b)) resultPtr := add(resultPtr, 1) resultLen := add(resultLen, 1)
                        switch eq(and(b, 0xFF), 0x6c) case 1 {state := add(state, 1)} case 0 {state := 13}}
                    // e
                    case 18 {mstore(resultPtr, shl(248, b)) resultPtr := add(resultPtr, 1) resultLen := add(resultLen, 1)
                        switch eq(and(b, 0xFF), 0x65) case 1 {state := add(state, 1)} case 0 {state := 13}}
                    // >
                    case 19 {
                        mstore(resultPtr, shl(248, b)) resultPtr := add(resultPtr, 1) resultLen := add(resultLen, 1)
                        switch eq(and(b, 0xFF), 0x3e)
                        case 1 {
                            // some svg magic
                            // insert "svg:nth-child(2) " to limit the scope of <style>
                            // chainrunner uses customized style for svg <rect> which messed up our pokers
                            mstore8(resultPtr, 0x73) resultPtr := add(resultPtr, 1) // s
                            mstore8(resultPtr, 0x76) resultPtr := add(resultPtr, 1) // v
                            mstore8(resultPtr, 0x67) resultPtr := add(resultPtr, 1) // g
                            mstore8(resultPtr, 0x3a) resultPtr := add(resultPtr, 1) // :
                            mstore8(resultPtr, 0x6e) resultPtr := add(resultPtr, 1) // n
                            mstore8(resultPtr, 0x74) resultPtr := add(resultPtr, 1) // t
                            mstore8(resultPtr, 0x68) resultPtr := add(resultPtr, 1) // h
                            mstore8(resultPtr, 0x2d) resultPtr := add(resultPtr, 1) // -
                            mstore8(resultPtr, 0x63) resultPtr := add(resultPtr, 1) // c
                            mstore8(resultPtr, 0x68) resultPtr := add(resultPtr, 1) // h
                            mstore8(resultPtr, 0x69) resultPtr := add(resultPtr, 1) // i
                            mstore8(resultPtr, 0x6c) resultPtr := add(resultPtr, 1) // l
                            mstore8(resultPtr, 0x64) resultPtr := add(resultPtr, 1) // d
                            mstore8(resultPtr, 0x28) resultPtr := add(resultPtr, 1) // (
                            mstore8(resultPtr, 0x32) resultPtr := add(resultPtr, 1) // 2
                            mstore8(resultPtr, 0x29) resultPtr := add(resultPtr, 1) // )
                            mstore8(resultPtr, 0x20) resultPtr := add(resultPtr, 1) // " "
                            resultLen := add(resultLen, 17)
                            state := add(state, 1)
                        } case 0 {state := 13}}
                    // store char string until "
                    case 20 {switch eq(and(b, 0xFF), 0x22) case 1 {state := add(state, 1)} case 0 {
                        mstore(resultPtr, shl(248, b)) resultPtr := add(resultPtr, 1) resultLen := add(resultLen, 1)}
                    }
                    default {}
                }
            }
            mstore(result, resultLen)
        }
        return result;
    }

    // @author onchain shufflers
    // optimized decoder: one pass decode, string slicing and decode
    // input: base64 encoded json with format
    //        {"name":"Noun 0", "description":"Nouns DAO", "image": "data:image/svg+xml;base64,aGVsbG8="}
    // output: decoded base64 string from the "image" field, i.e. "hello"
    // ref: Decoding Base64 with padding, https://en.wikipedia.org/wiki/Base64
    function decodeGetJsonImgDecoded(string memory _data) internal pure returns (bytes memory) {
        bytes memory data = bytes(_data);

        if (data.length == 0) return new bytes(0);
        require(data.length % 4 == 0, "invalid base64 decoder input");

        // load the table into memory
        bytes memory table = TABLE_DECODE;

        // add some extra buffer at the end required for the writing
        bytes memory result = new bytes((data.length / 4) * 3 + 32);

        assembly {
            // prepare the lookup table
            let tablePtr := add(table, 1)

            // input ptr
            let dataPtr := data
            let endPtr := add(dataPtr, mload(data))

            // result ptr, jump over length
            let resultPtr := add(result, 32)

            let state := 0 // FSM state
            let resultLen := 0
            // run over the input, 4 characters at a time
            for {} lt(dataPtr, endPtr) {}
            {
               // read 4 characters
               dataPtr := add(dataPtr, 4)
               let input := mload(dataPtr)

               // write 3 bytes
               let output := add(
                   add(
                       shl(18, and(mload(add(tablePtr, and(shr(24, input), 0xFF))), 0xFF)),
                       shl(12, and(mload(add(tablePtr, and(shr(16, input), 0xFF))), 0xFF))),
                   add(
                       shl( 6, and(mload(add(tablePtr, and(shr( 8, input), 0xFF))), 0xFF)),
                               and(mload(add(tablePtr, and(        input , 0xFF))), 0xFF)
                    )
                )

                input := 0
                for { let i := 0 } lt(i, 3) { i := add(i, 1) } {
                    let b := byte(i, shl(232, output)) // top three char

                    switch state
                        // "
                        case 0 { switch eq(and(b, 0xFF), 0x22) case 1 { state := add(state, 1) } }
                        // i
                        case 1 { switch eq(and(b, 0xFF), 0x69) case 1 { state := add(state, 1) } case 0 { state := 0 } }
                        // m
                        case 2 { switch eq(and(b, 0xFF), 0x6d) case 1 { state := add(state, 1) } case 0 { state := 0 } }
                        // a
                        case 3 { switch eq(and(b, 0xFF), 0x61) case 1 { state := add(state, 1) } case 0 { state := 0 } }
                        // g
                        case 4 { switch eq(and(b, 0xFF), 0x67) case 1 { state := add(state, 1) } case 0 { state := 0 } }
                        // e
                        case 5 { switch eq(and(b, 0xFF), 0x65) case 1 { state := add(state, 1) } case 0 { state := 0 } }
                        // "
                        case 6 { switch eq(and(b, 0xFF), 0x22) case 1 { state := add(state, 1) } case 0 { state := 0 } }
                        // until ,
                        case 7 { switch eq(and(b, 0xFF), 0x2c) case 1 { state := add(state, 1) } case 0 {  } }
                        // start processing embeded base64 string, until "
                        case 8 { switch eq(and(b, 0xFF), 0x22) // if "
                            case 1 { state := 100 } // exit
                            case 0 { // store 1st char
                                mstore8(resultPtr, b)
                                resultPtr := add(resultPtr, 1)
                                state := add(state, 1)
                            }
                        }
                        case 9 { // store 2nd char
                            mstore8(resultPtr, b)
                            resultPtr := add(resultPtr, 1)
                            state := add(state, 1)
                        }

                        case 10 { switch eq(and(b, 0xFF), 0x3d) // if =
                            case 1 { // decode and exit
                                resultPtr := sub(resultPtr, 2)
                                input := shr(224, mload(resultPtr))
                                data := add(
                                    add(
                                        shl(18, and(mload(add(tablePtr, and(shr(24, input), 0xFF))), 0xFF)),
                                        shl(12, and(mload(add(tablePtr, and(shr(16, input), 0xFF))), 0xFF))),
                                    add(
                                        shl(6, and(mload(add(tablePtr, and(shr( 8, input), 0xFF))), 0xFF)),
                                               and(mload(add(tablePtr, and(        input , 0xFF))), 0xFF)
                                    )
                                )
                                mstore(resultPtr, shl(232, data))
                                resultLen := add(resultLen, 1)
                                state := 100
                            } case 0 { // store 3rd char
                                mstore8(resultPtr, b)
                                resultPtr := add(resultPtr, 1)
                                state := add(state, 1)
                            }
                        }
                        case 11 { switch eq(and(b, 0xFF), 0x3d) // if =
                            case 1 { // decode and exit
                                resultPtr := sub(resultPtr, 3)
                                input := shr(224, mload(resultPtr))
                                data := add(
                                    add(
                                        shl(18, and(mload(add(tablePtr, and(shr(24, input), 0xFF))), 0xFF)),
                                        shl(12, and(mload(add(tablePtr, and(shr(16, input), 0xFF))), 0xFF))),
                                    add(
                                        shl(6, and(mload(add(tablePtr, and(shr( 8, input), 0xFF))), 0xFF)),
                                               and(mload(add(tablePtr, and(        input , 0xFF))), 0xFF)
                                    )
                                )
                                mstore(resultPtr, shl(232, data))
                                resultLen := add(resultLen, 2)
                                state := 100
                            } case 0 { // decode and continue parsing
                                mstore8(resultPtr, b)
                                resultPtr := add(resultPtr, 1)
                                resultPtr := sub(resultPtr, 4)
                                input := shr(224, mload(resultPtr))
                                data := add(
                                    add(
                                        shl(18, and(mload(add(tablePtr, and(shr(24, input), 0xFF))), 0xFF)),
                                        shl(12, and(mload(add(tablePtr, and(shr(16, input), 0xFF))), 0xFF))),
                                    add(
                                        shl(6, and(mload(add(tablePtr, and(shr( 8, input), 0xFF))), 0xFF)),
                                               and(mload(add(tablePtr, and(        input , 0xFF))), 0xFF)
                                    )
                                )
                                mstore(resultPtr, shl(232, data))
                                resultPtr := add(resultPtr, 3)
                                resultLen := add(resultLen, 3)
                            }
                            state := 8
                        }
                        default { }
                }
            }
            mstore(result, resultLen)
        }
        return result;
    }
}
// File: contracts/OriginalPunkProxy.sol



// SPDX-License-Identifier: GPL-3.0
pragma solidity ^0.8.6;


abstract contract OriginalPunkProxy {
    mapping (uint => address) public punkIndexToAddress;
}

// File: @openzeppelin/contracts/utils/Context.sol



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

pragma solidity ^0.8.0;

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

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

// File: @openzeppelin/contracts/token/ERC721/IERC721.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC721/IERC721.sol)

pragma solidity ^0.8.0;

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

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

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

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

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

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

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

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

    /**
     * @dev Transfers `tokenId` token from `from` to `to`.
     *
     * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address from,
        address to,
        uint256 tokenId
    ) external;

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

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

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

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

// File: @openzeppelin/contracts/utils/introspection/IERC165.sol



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

pragma solidity ^0.8.0;

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

// File: erc721a/contracts/IERC721A.sol



// SPDX-License-Identifier: MIT
// ERC721A Contracts v4.2.2
// Creator: Chiru Labs

pragma solidity ^0.8.4;

/**
 * @dev Interface of ERC721A.
 */
interface IERC721A {
    /**
     * The caller must own the token or be an approved operator.
     */
    error ApprovalCallerNotOwnerNorApproved();

    /**
     * The token does not exist.
     */
    error ApprovalQueryForNonexistentToken();

    /**
     * The caller cannot approve to their own address.
     */
    error ApproveToCaller();

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

    /**
     * Cannot mint to the zero address.
     */
    error MintToZeroAddress();

    /**
     * The quantity of tokens minted must be more than zero.
     */
    error MintZeroQuantity();

    /**
     * The token does not exist.
     */
    error OwnerQueryForNonexistentToken();

    /**
     * The caller must own the token or be an approved operator.
     */
    error TransferCallerNotOwnerNorApproved();

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

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

    /**
     * Cannot transfer to the zero address.
     */
    error TransferToZeroAddress();

    /**
     * The token does not exist.
     */
    error URIQueryForNonexistentToken();

    /**
     * The `quantity` minted with ERC2309 exceeds the safety limit.
     */
    error MintERC2309QuantityExceedsLimit();

    /**
     * The `extraData` cannot be set on an unintialized ownership slot.
     */
    error OwnershipNotInitializedForExtraData();

    // =============================================================
    //                            STRUCTS
    // =============================================================

    struct TokenOwnership {
        // The address of the owner.
        address addr;
        // Stores the start time of ownership with minimal overhead for tokenomics.
        uint64 startTimestamp;
        // Whether the token has been burned.
        bool burned;
        // Arbitrary data similar to `startTimestamp` that can be set via {_extraData}.
        uint24 extraData;
    }

    // =============================================================
    //                         TOKEN COUNTERS
    // =============================================================

    /**
     * @dev Returns the total number of tokens in existence.
     * Burned tokens will reduce the count.
     * To get the total number of tokens minted, please see {_totalMinted}.
     */
    function totalSupply() external view returns (uint256);

    // =============================================================
    //                            IERC165
    // =============================================================

    /**
     * @dev Returns true if this contract implements the interface defined by
     * `interfaceId`. See the corresponding
     * [EIP section](https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified)
     * to learn more about how these ids are created.
     *
     * This function call must use less than 30000 gas.
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);

    // =============================================================
    //                            IERC721
    // =============================================================

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

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

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

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

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

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

    /**
     * @dev Equivalent to `safeTransferFrom(from, to, tokenId, '')`.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId
    ) external;

    /**
     * @dev Transfers `tokenId` from `from` to `to`.
     *
     * WARNING: Usage of this method is discouraged, use {safeTransferFrom}
     * whenever possible.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token
     * by either {approve} or {setApprovalForAll}.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address from,
        address to,
        uint256 tokenId
    ) external;

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

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

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

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

    // =============================================================
    //                        IERC721Metadata
    // =============================================================

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

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

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

    // =============================================================
    //                           IERC2309
    // =============================================================

    /**
     * @dev Emitted when tokens in `fromTokenId` to `toTokenId`
     * (inclusive) is transferred from `from` to `to`, as defined in the
     * [ERC2309](https://eips.ethereum.org/EIPS/eip-2309) standard.
     *
     * See {_mintERC2309} for more details.
     */
    event ConsecutiveTransfer(uint256 indexed fromTokenId, uint256 toTokenId, address indexed from, address indexed to);
}