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



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

pragma solidity ^0.8.0;

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

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

    uint256 private _status;

    constructor() {
        _status = _NOT_ENTERED;
    }

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

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

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

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

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

// File: contracts/EIP712.sol



// SPDX-License-Identifier: AGPL-3.0-only+VPL
pragma solidity ^0.8.16;

abstract contract EIP712 {
  bytes32 constant EIP712DOMAIN_TYPEHASH = keccak256 (
    "EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"
  );

  struct EIP712Domain {
    string  name;
    string  version;
    uint256 chainId;
    address verifyingContract;
  }

  bytes internal personalSignPrefix = "\x19Ethereum Signed Message:\n";

  bytes32 immutable public DOMAIN_SEPARATOR;

  constructor (
    string memory _name,
    string memory _version
  ) {
    uint chainId;
    assembly {
      chainId := chainid()
    }
    DOMAIN_SEPARATOR = hash(EIP712Domain({
      name: _name,
      version: _version,
      chainId: chainId,
      verifyingContract: address(this)
    }));
  }

  function hash (
    EIP712Domain memory eip712Domain
  ) internal pure returns (bytes32) {
    return keccak256(abi.encode(
      EIP712DOMAIN_TYPEHASH,
      keccak256(bytes(eip712Domain.name)),
      keccak256(bytes(eip712Domain.version)),
      eip712Domain.chainId,
      eip712Domain.verifyingContract
    ));
  }

  function parseSignature (
    bytes memory signature
  ) internal pure returns (uint8 v, bytes32 r, bytes32 s) {
    // ecrecover takes the signature parameters, and the only way to get them
    // currently is to use assembly.
    // solhint-disable-next-line no-inline-assembly
    assembly {
      r := mload(add(signature, 0x20))
      s := mload(add(signature, 0x40))
      v := byte(0, mload(add(signature, 0x60)))
    }
    return (v,r,s);
  }
}


// File: contracts/Shishi.sol



// SPDX-License-Identifier: AGPL-3.0-only+VPL
pragma solidity ^0.8.16;

import "erc721a/contracts/extensions/ERC721ABurnable.sol";
import "solady/src/auth/Ownable.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";

import "./EIP712.sol";

/// Thrown if the base token metadata URI is locked to updates.
error BaseURILocked ();

/// Thrown if an invalid signature is being supplied by the caller.
error CannotClaimInvalidSignature ();

/// Thrown if the signature supplied does not match the current time.
error NotStartedYet ();

/// Thrown if the caller is trying to overmint.
error InvalidQuantity ();

/// Thrown if the caller did not supply enough payment.
error NotEnoughPayment ();

/// Thrown if the public mint has not yet started.
error PublicMintNotStarted ();

/// Thrown if there are no more Shishis left to mint.
error OutOfStock ();

/**
  This is thrown if a particular `msg.sender` (or, additionally, a `tx.origin`
  acting on behalf of smart contract caller) has run out of permitted mints.
  This does not and is not meant to protect against Sybil attacks originated by
  multiple different accounts.
*/
error OutOfMints ();

// Thrown if sweeping funds from this contract fails.
error SweepingTransferFailed ();

/**
  @custom:benediction DEVS BENEDICAT ET PROTEGAT CONTRACTVM MEVM
  @title Shishi. Ever dream this girl?
  @author Tim Clancy <tim-clancy.eth>
  @author many loving friendly network spirits
  @custom:version 1.0
  
  Shishi is a generative art project by shirosama.eth; yippiee!

  @custom:date December 28th, 2023.
  @custom:terry "I am in an angel prison or some shit."
*/
contract Shishi is EIP712, ERC721ABurnable, Ownable, ReentrancyGuard {

  /**
    Store the provenance hash. This is computed as the keccak256 hash of the
    images for all Shishis, in token ID order, concatenated together and then
    hashed one last time forever. We understand that this is only a weak
    guarantee of honesty--it proves that we committed to the art and its order
    prior to beginning the mint but does nothing to trustlessly conceal the
    specific metadata of particular Shishis ahead of time. You'll just have to
    deal with that; schemes which apply provably-randomized offsets to the
    provenance data are very difficult to reconcile with instant reveals.
  */
  bytes32 constant private provenance =
    0x33f697f5034dee7c24e34d7c737bab50920b3cbd1a4854e01230b8568d910dae;

  /// A constant hash of the mint operation's signature.
  bytes32 constant private MINT_TYPEHASH = keccak256(
    "mint(address _minter,uint64 _start,uint8 _oh,uint8 _remi,uint8 _paid)"
  );

  /// Track the base token metadata URI.
  string internal baseURI;

  /// Track whether the base token metadata URI is locked to future changes.
  bool private baseURILocked;

  /// Track the total supply cap on the number of Shishis that may be minted.
  uint256 private cap;

  /// Track the address of the authorized whitelist signer.
  address private signer;

  /// Track the start time of whitelist phase two.
  uint64 private startTwo;

  /// Track the start time of the public mint.
  uint64 private startThree;

  /**
    Right about here is where I got lazy and began to regret my decision of
    doing this entire thing with fancy signatures and a single mint function.

    Thank you Vx loves and kisses mwah mwah.

    @param oh Track a caller's expended Oh I See mints.
    @param remi Track a caller's expended Milady/Remilio mints.
    @param paid Track a caller's expended paid mints.
    @param callerPub Track a caller's utilized public mints.
    @param originPub Track a transaction originator's utilized public mints.
  */
  struct MintCounts
  {
    uint8 oh;
    uint8 remi;
    uint8 paid;
    uint8 callerPub;
    uint8 originPub;
  }

  /// Store tracked inter-round receipt information.
  mapping ( address => MintCounts ) internal mintCounts;

  /// Track the number of utilized FCFS Milady/Remilio mints.
  uint256 public fcfs;

  /**
    Construct an instance of the Shishi contract.

    @param _owner The initial owner of this contract.
    @param _initialBaseURI The initial base token metadata URI to use.
    @param _cap The total supply cap on the number of Shishis.
    @param _signer The address of the initial whitelist signer.
    @param _startTwo The start time of whitelist phase two.
    @param _startThree The start time of public minting.
  */
  constructor (
    address _owner,
    string memory _initialBaseURI,
    uint256 _cap,
    address _signer,
    uint64 _startTwo,
    uint64 _startThree
  ) EIP712("Shishi", "1") ERC721A("Shishi", "SHISHI") {
    _initializeOwner(_owner);
    baseURI = _initialBaseURI;
    cap = _cap;
    signer = _signer;
    startTwo = _startTwo;
    startThree = _startThree;
    _mint(_owner, 1);
  }

  /**
    Override the starting index of the first Shishi.

    @return _ The token ID of the first Shishi.
  */
  function _startTokenId (
  ) internal view virtual override returns (uint256) {
    return 1;
  }

  /**
    Override the `_baseURI` used in our parent contract with our set value.

    @return _ The base token metadata URI.
  */
  function _baseURI (
  ) internal view virtual override returns (string memory) {
    return baseURI;
  }

  /**
    Allow the contract owner to set the base token metadata URI.

    @param _newBaseURI The new base token metadata URI to set.
    @custom:throws BaseURILocked if the base token metadata URI is locked
      against future changes.
  */
  function setBaseURI (
    string memory _newBaseURI
  ) external payable onlyOwner {
    if (baseURILocked) {
      revert BaseURILocked();
    } else {
      baseURI = _newBaseURI;
    }
  }

  /**
    Allow the contract owner to permanently lock base URI changes.
  */
  function lockBaseURI (
  ) external payable onlyOwner {
    baseURILocked = true;
  }

  /**
    Allow the contract owner to set the authorized whitelist signer.

    @param _signer The new authorized signer.
  */
  function setSigner (
    address _signer
  ) external payable onlyOwner {
    signer = _signer;
  }

  /**
    Allow the contract owner to set the whitelist phase times.

    @param _startTwo The new phase two time.
    @param _startThree The new phase three time.
  */
  function setPhases (
    uint64 _startTwo,
    uint64 _startThree
  ) external payable onlyOwner {
    startTwo = _startTwo;
    startThree = _startThree;
  }

  /**
    A private helper function to validate a signature supplied for mints.
    This function constructs a digest and verifies that the signature signer was
    the authorized address we expect.

    @param _minter The caller attempting to mint.
    @param _start The start time of the minting signature.
    @param _oh The amount of free Oh I See mints the caller is trying to claim.
    @param _remi The amount of free Milady/Remilio mints the caller is trying
      to claim.
    @param _paid The amount of paid mints the caller is trying to claim.
    @param _v The recovery byte of the signature.
    @param _r Half of the ECDSA signature pair.
    @param _s Half of the ECDSA signature pair.
  */
  function validClaim (
    address _minter,
    uint64 _start,
    uint8 _oh,
    uint8 _remi,
    uint8 _paid,
    uint8 _v,
    bytes32 _r,
    bytes32 _s
  ) private view returns (bool) {
    bytes32 digest = keccak256(
      abi.encodePacked(
        "\x19\x01",
        DOMAIN_SEPARATOR,
        keccak256(
          abi.encode(
            MINT_TYPEHASH,
            _minter,
            _start,
            _oh,
            _remi,
            _paid
          )
        )
      )
    );

    // The claim is validated if it was signed by our authorized signer.
    return ecrecover(digest, _v, _r, _s) == signer;
  }

  /**
    Allow the caller to mint Shishis.

    @param _quantity The number of Shishi to mint.

    @custom:throws CannotClaimInvalidSignature if an invalid signature is
      supplied by the caller.
    @custom:throws NotStartedYet if a signature is submitted too early.
    @custom:throws InvalidQuantity if a caller is trying to mint too much.
    @custom:throws NotEnoughPayment if a caller is underpaying.
    @custom:throws PublicMintNotStarted if a non-whitelisted caller is early.
    @custom:throws OutOfMints if the caller has exhausted their mint allowance.
    @custom:throws OutOfStock if all of the Shishis have been minted.
  */
  function mint (
    uint64 _start,
    uint8 _oh,
    uint8 _remi,
    uint8 _paid,
    uint8 _quantity,
    uint8 _v,
    bytes32 _r,
    bytes32 _s
  ) external payable nonReentrant {

    // Determine mint price based on time.
    uint256 _price = 0.033 ether;
    if (block.timestamp > startThree) {
      _price = 0.04 ether;
    }

    // If a signature is provided, validate it.
    if (_start != 0) {
      bool validSignature = validClaim(
        msg.sender,
        _start,
        _oh,
        _remi,
        _paid,
        _v,
        _r,
        _s
      );
      if (!validSignature) {
        revert CannotClaimInvalidSignature();
      }

      // Validate the minting phase.
      if (block.timestamp < _start) {
        revert NotStartedYet();
      }

      // Reduce by previous utilized allowance.
      _oh -= mintCounts[msg.sender].oh;
      _remi -= mintCounts[msg.sender].remi;
      _paid -= mintCounts[msg.sender].paid;
      mintCounts[msg.sender].oh += _oh;
      mintCounts[msg.sender].remi += _remi;
      mintCounts[msg.sender].paid += _paid;

      // Validate sensible quantity.
      if (_quantity > (_oh + _remi + _paid)) {
        revert InvalidQuantity();
      }

      // Handle the special FCFS Milady/Remilio pool.
      if (block.timestamp > startTwo) {
        if (fcfs >= 300) {
          _quantity -= _remi;
        } else {
          fcfs += _remi;
        }
      }

      // Validate payment.
      uint256 _paidQuantity = _quantity - _remi - _oh;
      if (msg.value < _paidQuantity * _price) {
        revert NotEnoughPayment();
      }
    
    // If no signature is provided, we must try for the public mint.
    } else {
      if (block.timestamp < startThree) {
        revert PublicMintNotStarted();
      }

      // Validate the public mint cap.
      if (
        mintCounts[msg.sender].callerPub + _quantity > 2 ||
        mintCounts[tx.origin].originPub + _quantity > 2
      ) {
        revert OutOfMints();
      }

      // Validate payment.
      if (msg.value < _quantity * _price) {
        revert NotEnoughPayment();
      }
      mintCounts[msg.sender].callerPub += _quantity;
      mintCounts[tx.origin].originPub += _quantity;
    }

    // Prevent the overminting of Shishis.
    if (_totalMinted() + _quantity > cap) {
      revert OutOfStock();
    }

    // Mint the Shishi.
    _mint(msg.sender, _quantity);
  }

  /**
    Allow the owner to sweep Ether from the contract and send it to another
    address. This allows the owner of the shop to withdraw their funds after
    the sale is completed.

    @param _destination The address to send the swept tokens to.
    @param _amount The amount of token to sweep.

    @custom:throws SweepingTransferFailed if the balance could not transfer.
  */
  function sweep (
    address _destination,
    uint256 _amount
  ) external payable onlyOwner {
    (bool success, ) = payable(_destination).call{ value: _amount }("");
    if (!success) { revert SweepingTransferFailed(); }
  }
 }


// File: erc721a/contracts/ERC721A.sol



// SPDX-License-Identifier: MIT
// ERC721A Contracts v4.2.3
// 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 {
    // Bypass for a `--via-ir` bug (https://github.com/chiru-labs/ERC721A/pull/364).
    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 payable 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 {
        _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].value`.
        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 payable 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 payable 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 payable 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.
            // The duplicated `log4` removes an extra check and reduces stack juggling.
            // The assembly, together with the surrounding Solidity code, have been
            // delicately arranged to nudge the compiler into producing optimized opcodes.
            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`.
                )

                // The `iszero(eq(,))` check ensures that large values of `quantity`
                // that overflows uint256 will make the loop run out of gas.
                // The compiler will optimize the `iszero` away for performance.
                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 0xa0 bytes to keep the free memory pointer 32-byte word aligned.
            // We will need 1 word for the trailing zeros padding, 1 word for the length,
            // and 3 words for a maximum of 78 digits. Total: 5 * 0x20 = 0xa0.
            let m := add(mload(0x40), 0xa0)
            // Update the free memory pointer to allocate.
            mstore(0x40, m)
            // Assign the `str` to the end.
            str := sub(m, 0x20)
            // Zeroize the slot after the string.
            mstore(str, 0)

            // 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: erc721a/contracts/extensions/ERC721ABurnable.sol



// SPDX-License-Identifier: MIT
// ERC721A Contracts v4.2.3
// Creator: Chiru Labs

pragma solidity ^0.8.4;

import './IERC721ABurnable.sol';
import '../ERC721A.sol';

/**
 * @title ERC721ABurnable.
 *
 * @dev ERC721A token that can be irreversibly burned (destroyed).
 */
abstract contract ERC721ABurnable is ERC721A, IERC721ABurnable {
    /**
     * @dev Burns `tokenId`. See {ERC721A-_burn}.
     *
     * Requirements:
     *
     * - The caller must own `tokenId` or be an approved operator.
     */
    function burn(uint256 tokenId) public virtual override {
        _burn(tokenId, true);
    }
}

// File: erc721a/contracts/extensions/IERC721ABurnable.sol



// SPDX-License-Identifier: MIT
// ERC721A Contracts v4.2.3
// Creator: Chiru Labs

pragma solidity ^0.8.4;

import '../IERC721A.sol';

/**
 * @dev Interface of ERC721ABurnable.
 */
interface IERC721ABurnable is IERC721A {
    /**
     * @dev Burns `tokenId`. See {ERC721A-_burn}.
     *
     * Requirements:
     *
     * - The caller must own `tokenId` or be an approved operator.
     */
    function burn(uint256 tokenId) external;
}

// File: erc721a/contracts/IERC721A.sol



// SPDX-License-Identifier: MIT
// ERC721A Contracts v4.2.3
// 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();

    /**
     * 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 payable;

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

    /**
     * @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 payable;

    /**
     * @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 payable;

    /**
     * @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);
}

// File: solady/src/auth/Ownable.sol



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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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