// File: contracts/base/UFO.sol



// SPDX-License-Identifier: MIT
                                                                                                                   
//    000000000                        UUUUUUUU     UUUUUUUUFFFFFFFFFFFFFFFFFFFFFF     OOOOOOOOO        SSSSSSSSSSSSSSS 
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//0:::::0     0:::::0     x::::::::x     U:::::D     D:::::U   F::::::FFFFFFFFFF   O:::::O     O:::::O       SSSSSS::::S 
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//  000000000     xxxxxxx      xxxxxxx     UUUUUUUUU      FFFFFFFFFFF                OOOOOOOOO      SSSSSSSSSSSSSSS   

//Fully Generated on Chain Animated UFO NFTs @0xUFOs                                                                                                                      

pragma solidity ^0.8.19;

import "../lib/ERC721Enumerable.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "./IUFOIdentifier.sol";
import "../extension/Royalty.sol";
import "../extension/DefaultOperatorFilterer.sol";
import "../extension/ContractMetadata.sol";
import "@openzeppelin/contracts/utils/cryptography/MerkleProof.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";

contract UFOS is ERC721Enumerable, ContractMetadata, Royalty, ReentrancyGuard, Ownable, DefaultOperatorFilterer {
    
    event SeedUpdated(uint256 indexed tokenId, uint256 seed);
    event MintPublicSale(address indexed minter, uint256 indexed tokens);
    event ReserveTokens(uint256 indexed tokens);
    event MintPreSale(address indexed minter, uint256 indexed tokens);
    event SetPreSaleMerkleRoot(bytes32 indexed root);
    event SetSaleState(SaleState indexed state);

    mapping(uint256 => uint256) internal seeds;
    mapping(address => uint256) public preSaleMintCounts; 
    
    uint256 public MAX_TOTAL_SUPPLY = 851;
    uint256 public numReservedTokens;
    uint256 public constant MAX_RESERVE_TOKENS = 0;
    uint256 public constant MAX_PRE_SALE_MINTS = 1;
    uint256 public PRE_SALE_PRICE = 0 ether;
    uint256 public PUBLIC_SALE_PRICE = 0.01 ether;
    uint256 nextTokenId = _owners.length;
    
    IUFOIdentifier public identifier;
    address public vault;
    bool public canUpdateSeed = true;
    string public provenanceHash;
    bytes32 private preSaleListMerkleRoot;

    enum SaleState {
        Inactive,
        PreSale,
        PublicSale
    }
    
    SaleState public saleState = SaleState.PublicSale;

    constructor(
        IUFOIdentifier newIdentifier,
        address _vault,
        string memory _name,
        string memory _symbol,
        address _royaltyRecipient,
        uint128 _royaltyBps
        ) ERC721(_name, _symbol) {
        _setupDefaultRoyaltyInfo(_royaltyRecipient, _royaltyBps);
        _setOperatorRestriction(true);
        identifier = newIdentifier;
        vault = _vault;
    }

    modifier preSaleActive() {
        require(saleState == SaleState.PreSale, "Pre sale is not open");
        _;
    }
 
    modifier publicSaleActive() {
        require(saleState == SaleState.PublicSale, "Public sale is not open");
        _;
    }
    
    modifier maxTokensPerPreSaleMint(uint256 numberOfTokens) {
        require(
            preSaleMintCounts[msg.sender] + numberOfTokens <= MAX_PRE_SALE_MINTS,
            "Exceeds pre sale mint max number"
    );
        _;
    }

    modifier canMint(uint256 numberOfTokens) {
        require(
            nextTokenId + numberOfTokens <=
                MAX_TOTAL_SUPPLY - MAX_RESERVE_TOKENS + numReservedTokens,
            "Insufficient UFOs remaining"
        );
        _;
    }

    modifier canReserveTokens(uint256 numberOfTokens) {
        require(
            numReservedTokens + numberOfTokens <= MAX_RESERVE_TOKENS,
            "Insufficient token reserve"
        );
        require(
             nextTokenId + numberOfTokens <= MAX_TOTAL_SUPPLY,
            "Insufficient tokens remaining"
        );
        _;
    }

    modifier isCorrectPayment(uint256 price, uint256 numberOfTokens) {
        require(
            price * numberOfTokens == msg.value,
            "Incorrect ETH value sent"
        );
        _;
    }

    modifier hasAddresses(address[] calldata addresses) {
        require(addresses.length > 0, "Addresses array empty");
        _;
    }

    modifier isValidPreSaleAddress(bytes32[] calldata merkleProof) {
        require(
            MerkleProof.verify(
                merkleProof,
                preSaleListMerkleRoot,
                keccak256(abi.encodePacked(msg.sender))
            ),
            "Address not in list"
        );
        _;
    }

    modifier isExistingToken(uint256 tokenId) {
        require(_exists(tokenId), "Non-existent token");
        _;
    }



     /*//////////////////////////////////////////////////////////////
                            ERC165 Logic
    //////////////////////////////////////////////////////////////*/

    /// @dev See ERC165: https://eips.ethereum.org/EIPS/eip-165
    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC721Enumerable) returns (bool) {
        return
            interfaceId == 0x01ffc9a7 || // ERC165 Interface ID for ERC165
            interfaceId == 0x80ac58cd || // ERC165 Interface ID for ERC721
            interfaceId == 0x5b5e139f || // ERC165 Interface ID for ERC721Metadata
            interfaceId == type(IERC2981).interfaceId; // ERC165 ID for ERC2981
    }

     /// @notice Returns whether a given address is the owner, or approved to transfer an NFT.
    function isApprovedOrOwner(address _operator, uint256 _tokenId)
        public
        view
        virtual
        returns (bool isApprovedOrOwnerOf)
    {
        address owner = ownerOf(_tokenId);
        isApprovedOrOwnerOf = (_operator == owner ||
        isApprovedForAll(owner, _operator) ||
        getApproved(_tokenId) == _operator);
    }
    
    /*//////////////////////////////////////////////////////////////
                        ERC-721 overrides
    //////////////////////////////////////////////////////////////*/

   
    function setApprovalForAll(address operator, bool approved)
        public
        virtual
        override(ERC721, IERC721)
        onlyAllowedOperatorApproval(operator)
    {
        super.setApprovalForAll(operator, approved);
    }

   
    function approve(address operator, uint256 tokenId)
        public
        virtual
        override(ERC721, IERC721)
        onlyAllowedOperatorApproval(operator)
    {
        super.approve(operator, tokenId);
    }

    
    function transferFrom(
        address from,
        address to,
        uint256 tokenId
    ) public virtual override(ERC721, IERC721) onlyAllowedOperator(from) {
        super.transferFrom(from, to, tokenId);
    }

    
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId
    ) public virtual override(ERC721, IERC721) onlyAllowedOperator(from) {
        super.safeTransferFrom(from, to, tokenId);
    }

    
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId,
        bytes memory data
    ) public virtual override(ERC721, IERC721) onlyAllowedOperator(from) {
        super.safeTransferFrom(from, to, tokenId, data);
    }

   /*//////////////////////////////////////////////////////////////
                            Mint Functions
    //////////////////////////////////////////////////////////////*/
   function mint(uint32 numberOfTokens) 
        external payable 
        nonReentrant 
        publicSaleActive
        isCorrectPayment(PUBLIC_SALE_PRICE, numberOfTokens)
        canMint(numberOfTokens) {
         
    for (uint32 i = 0; i < numberOfTokens; i++) {
        seeds[nextTokenId] = generateSeed(nextTokenId);
        _mint(_msgSender(), nextTokenId);
        nextTokenId++;
    }
}


 function mintPreSale(uint32 numberOfTokens, bytes32[] calldata merkleProof)
        external
        payable
        nonReentrant
        preSaleActive
        isCorrectPayment(PRE_SALE_PRICE, numberOfTokens)
        canMint(numberOfTokens)
        isValidPreSaleAddress(merkleProof)
        maxTokensPerPreSaleMint(numberOfTokens)
    {
        preSaleMintCounts[msg.sender] = preSaleMintCounts[msg.sender] + numberOfTokens;
        for (uint32 i = 0; i < numberOfTokens; i++) {
        seeds[nextTokenId] = generateSeed(nextTokenId);
        _mint(_msgSender(), nextTokenId);
        nextTokenId++;
    }

        emit MintPreSale(msg.sender, numberOfTokens);
    }

  function burn(uint256 tokenId) public {
        require(_isApprovedOrOwner(_msgSender(), tokenId), "Not approved to burn.");
        delete seeds[tokenId];
        _burn(tokenId);
    }

    function getSeed(uint256 tokenId) public view returns (uint256) {
        require(_exists(tokenId), "UFO does not exist.");
        return seeds[tokenId];
    }

    function tokenURI(uint256 tokenId) public view returns (string memory) {
        require(_exists(tokenId), "UFO does not exist.");
        uint256 seed = seeds[tokenId];
        return identifier.tokenURI(tokenId, seed);
    }

    function generateSeed(uint256 tokenId) private view returns (uint256) {
        uint256 r = random(tokenId);
        uint256 domeSeed = 100 * (r % 11 + 10) + ((r >> 48) % 20 + 10);
        uint256 hullSeed = 100 * ((r >> 96) % 11 + 10) + ((r >> 96) % 20 + 10);
        uint256 powercoreSeed = 100 * ((r >> 144) % 11 + 10) + ((r >> 144) % 20 + 10);
        uint256 propulsionSeed = 100 * ((r >> 192) % 7 + 10) + ((r >> 192) % 20 + 10);
        return 10000 * (10000 * (10000 * domeSeed + hullSeed) + powercoreSeed) + propulsionSeed;
    }
    
    function random(uint256 tokenId) private view returns (uint256 pseudoRandomness) {
        pseudoRandomness = uint256(
            keccak256(abi.encodePacked(blockhash(block.number - 1), tokenId))
        );

        return pseudoRandomness;
    }

   /*//////////////////////////////////////////////////////////////
                            Owner Only Functions
    //////////////////////////////////////////////////////////////*/

     function setPublicSaleActive() external onlyOwner {
        saleState = SaleState.PublicSale;

        emit SetSaleState(SaleState.PublicSale);
    }

    function setPreSaleActive() external onlyOwner {
        saleState = SaleState.PreSale;

        emit SetSaleState(SaleState.PreSale);
    }

    function setSaleInactive() external onlyOwner {
        saleState = SaleState.Inactive;

        emit SetSaleState(SaleState.Inactive);
    }

  
    function setPreSaleListMerkleRoot(bytes32 merkleRoot) external onlyOwner {
        preSaleListMerkleRoot = merkleRoot;

        emit SetPreSaleMerkleRoot(merkleRoot);
    }

    function setIdentifier (IUFOIdentifier newIdentifier) external onlyOwner {
        identifier = newIdentifier;
    }

     function withdraw() external onlyOwner {
        (bool success,) = vault.call{value: address(this).balance}("");
        require(success, "Withdrawal failed");
    }
    
    function updateSeed(uint256 tokenId, uint256 seed) external onlyOwner {
        require(canUpdateSeed, "Update Seed is False");
        seeds[tokenId] = seed;
        emit SeedUpdated(tokenId, seed);
    }

    function disableSeedUpdate() external onlyOwner {
        canUpdateSeed = false;
    }
   
    function setCost(uint256 _cost) public onlyOwner {
        PUBLIC_SALE_PRICE = _cost;
    }

    function setPresaleCost(uint256 _PreCost) public onlyOwner {
        PRE_SALE_PRICE = _PreCost;
    }
  
    function _canSetRoyaltyInfo() internal view virtual override returns (bool) {
        return msg.sender == owner();
    }

    /// @dev Returns whether operator restriction can be set in the given execution context.
    function _canSetOperatorRestriction() internal virtual override returns (bool) {
        return msg.sender == owner();
    }

      function _canSetContractURI() internal view virtual override returns (bool) {
        return msg.sender == owner();
    }

   
}
  
// File: @openzeppelin/contracts/security/ReentrancyGuard.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (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;
    }
}

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



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

pragma solidity ^0.8.0;

/**
 * @dev These functions deal with verification of Merkle Tree proofs.
 *
 * The tree and the proofs can be generated using our
 * https://github.com/OpenZeppelin/merkle-tree[JavaScript library].
 * You will find a quickstart guide in the readme.
 *
 * 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.
 * OpenZeppelin's JavaScript library generates merkle trees that are safe
 * against this attack out of the box.
 */
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 simultaneously proven to be a part of a merkle tree defined by
     * `root`, according to `proof` and `proofFlags` as described in {processMultiProof}.
     *
     * CAUTION: Not all merkle trees admit multiproofs. See {processMultiProof} for details.
     *
     * _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}
     *
     * CAUTION: Not all merkle trees admit multiproofs. See {processMultiProof} for details.
     *
     * _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 sibling nodes in `proof`. The reconstruction
     * proceeds by incrementally reconstructing all inner nodes by combining a leaf/inner node with either another
     * leaf/inner node or a proof sibling node, depending on whether each `proofFlags` item is true or false
     * respectively.
     *
     * CAUTION: Not all merkle trees admit multiproofs. To use multiproofs, it is sufficient to ensure that: 1) the tree
     * is complete (but not necessarily perfect), 2) the leaves to be proven are in the opposite order they are in the
     * tree (i.e., as seen from right to left starting at the deepest layer and continuing at the next layer).
     *
     * _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}.
     *
     * CAUTION: Not all merkle trees admit multiproofs. See {processMultiProof} for details.
     *
     * _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: contracts/extension/ContractMetadata.sol



// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

import "./interface/IContractMetadata.sol";

/**
 *  @title   Contract Metadata
 *  @notice  Thirdweb's `ContractMetadata` is a contract extension for any base contracts. It lets you set a metadata URI
 *           for you contract.
 *           Additionally, `ContractMetadata` is necessary for NFT contracts that want royalties to get distributed on OpenSea.
 */

abstract contract ContractMetadata is IContractMetadata {
    /// @notice Returns the contract metadata URI.
    string public override contractURI;

    /**
     *  @notice         Lets a contract admin set the URI for contract-level metadata.
     *  @dev            Caller should be authorized to setup contractURI, e.g. contract admin.
     *                  See {_canSetContractURI}.
     *                  Emits {ContractURIUpdated Event}.
     *
     *  @param _uri     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     */
    function setContractURI(string memory _uri) external override {
        if (!_canSetContractURI()) {
            revert("Not authorized");
        }

        _setupContractURI(_uri);
    }

    /// @dev Lets a contract admin set the URI for contract-level metadata.
    function _setupContractURI(string memory _uri) internal {
        string memory prevURI = contractURI;
        contractURI = _uri;

        emit ContractURIUpdated(prevURI, _uri);
    }

    /// @dev Returns whether contract metadata can be set in the given execution context.
    function _canSetContractURI() internal view virtual returns (bool);
}

// File: contracts/extension/DefaultOperatorFilterer.sol



// SPDX-License-Identifier: Apache 2.0
pragma solidity ^0.8.0;

/// @author thirdweb

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

/**
 * @title  DefaultOperatorFilterer
 * @notice Inherits from OperatorFilterer and automatically subscribes to the default OpenSea subscription.
 */
abstract contract DefaultOperatorFilterer is OperatorFilterer {
    address constant DEFAULT_SUBSCRIPTION = address(0x3cc6CddA760b79bAfa08dF41ECFA224f810dCeB6);

    constructor() OperatorFilterer(DEFAULT_SUBSCRIPTION, true) {}
}

// File: contracts/extension/Royalty.sol



// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

import "./interface/IRoyalty.sol";

/**
 *  @title   Royalty
 *  @notice  Thirdweb's `Royalty` is a contract extension to be used with any base contract. It exposes functions for setting and reading
 *           the recipient of royalty fee and the royalty fee basis points, and lets the inheriting contract perform conditional logic
 *           that uses information about royalty fees, if desired.
 *
 *  @dev     The `Royalty` contract is ERC2981 compliant.
 */

abstract contract Royalty is IRoyalty {
    /// @dev The (default) address that receives all royalty value.
    address private royaltyRecipient;

    /// @dev The (default) % of a sale to take as royalty (in basis points).
    uint16 private royaltyBps;

    /// @dev Token ID => royalty recipient and bps for token
    mapping(uint256 => RoyaltyInfo) private royaltyInfoForToken;

    /**
     *  @notice   View royalty info for a given token and sale price.
     *  @dev      Returns royalty amount and recipient for `tokenId` and `salePrice`.
     *  @param tokenId          The tokenID of the NFT for which to query royalty info.
     *  @param salePrice        Sale price of the token.
     *
     *  @return receiver        Address of royalty recipient account.
     *  @return royaltyAmount   Royalty amount calculated at current royaltyBps value.
     */
    function royaltyInfo(uint256 tokenId, uint256 salePrice)
        external
        view
        virtual
        override
        returns (address receiver, uint256 royaltyAmount)
    {
        (address recipient, uint256 bps) = getRoyaltyInfoForToken(tokenId);
        receiver = recipient;
        royaltyAmount = (salePrice * bps) / 10_000;
    }

    /**
     *  @notice          View royalty info for a given token.
     *  @dev             Returns royalty recipient and bps for `_tokenId`.
     *  @param _tokenId  The tokenID of the NFT for which to query royalty info.
     */
    function getRoyaltyInfoForToken(uint256 _tokenId) public view override returns (address, uint16) {
        RoyaltyInfo memory royaltyForToken = royaltyInfoForToken[_tokenId];

        return
            royaltyForToken.recipient == address(0)
                ? (royaltyRecipient, uint16(royaltyBps))
                : (royaltyForToken.recipient, uint16(royaltyForToken.bps));
    }

    /**
     *  @notice Returns the defualt royalty recipient and BPS for this contract's NFTs.
     */
    function getDefaultRoyaltyInfo() external view override returns (address, uint16) {
        return (royaltyRecipient, uint16(royaltyBps));
    }

    /**
     *  @notice         Updates default royalty recipient and bps.
     *  @dev            Caller should be authorized to set royalty info.
     *                  See {_canSetRoyaltyInfo}.
     *                  Emits {DefaultRoyalty Event}; See {_setupDefaultRoyaltyInfo}.
     *
     *  @param _royaltyRecipient   Address to be set as default royalty recipient.
     *  @param _royaltyBps         Updated royalty bps.
     */
    function setDefaultRoyaltyInfo(address _royaltyRecipient, uint256 _royaltyBps) external override {
        if (!_canSetRoyaltyInfo()) {
            revert("Not authorized");
        }

        _setupDefaultRoyaltyInfo(_royaltyRecipient, _royaltyBps);
    }

    /// @dev Lets a contract admin update the default royalty recipient and bps.
    function _setupDefaultRoyaltyInfo(address _royaltyRecipient, uint256 _royaltyBps) internal {
        if (_royaltyBps > 10_000) {
            revert("Exceeds max bps");
        }

        royaltyRecipient = _royaltyRecipient;
        royaltyBps = uint16(_royaltyBps);

        emit DefaultRoyalty(_royaltyRecipient, _royaltyBps);
    }

    /**
     *  @notice         Updates default royalty recipient and bps for a particular token.
     *  @dev            Sets royalty info for `_tokenId`. Caller should be authorized to set royalty info.
     *                  See {_canSetRoyaltyInfo}.
     *                  Emits {RoyaltyForToken Event}; See {_setupRoyaltyInfoForToken}.
     *
     *  @param _recipient   Address to be set as royalty recipient for given token Id.
     *  @param _bps         Updated royalty bps for the token Id.
     */
    function setRoyaltyInfoForToken(
        uint256 _tokenId,
        address _recipient,
        uint256 _bps
    ) external override {
        if (!_canSetRoyaltyInfo()) {
            revert("Not authorized");
        }

        _setupRoyaltyInfoForToken(_tokenId, _recipient, _bps);
    }

    /// @dev Lets a contract admin set the royalty recipient and bps for a particular token Id.
    function _setupRoyaltyInfoForToken(
        uint256 _tokenId,
        address _recipient,
        uint256 _bps
    ) internal {
        if (_bps > 10_000) {
            revert("Exceeds max bps");
        }

        royaltyInfoForToken[_tokenId] = RoyaltyInfo({ recipient: _recipient, bps: _bps });

        emit RoyaltyForToken(_tokenId, _recipient, _bps);
    }

    /// @dev Returns whether royalty info can be set in the given execution context.
    function _canSetRoyaltyInfo() internal view virtual returns (bool);
}

// File: contracts/base/IUFOIdentifier.sol



// SPDX-License-Identifier: MIT
                                                                                                                       
                                                                                                                       
//    000000000                        UUUUUUUU     UUUUUUUUFFFFFFFFFFFFFFFFFFFFFF     OOOOOOOOO        SSSSSSSSSSSSSSS 
//  00:::::::::00                      U::::::U     U::::::UF::::::::::::::::::::F   OO:::::::::OO    SS:::::::::::::::S
//00:::::::::::::00                    U::::::U     U::::::UF::::::::::::::::::::F OO:::::::::::::OO S:::::SSSSSS::::::S
//0:::::::000:::::::0                   UU:::::U     U:::::UUFF::::::FFFFFFFFF::::FO:::::::OOO:::::::OS:::::S     SSSSSSS
//0::::::0   0::::::0xxxxxxx      xxxxxxxU:::::U     U:::::U   F:::::F       FFFFFFO::::::O   O::::::OS:::::S            
//0:::::0     0:::::0 x:::::x    x:::::x U:::::D     D:::::U   F:::::F             O:::::O     O:::::OS:::::S            
//0:::::0     0:::::0  x:::::x  x:::::x  U:::::D     D:::::U   F::::::FFFFFFFFFF   O:::::O     O:::::O S::::SSSS         
//0:::::0 000 0:::::0   x:::::xx:::::x   U:::::D     D:::::U   F:::::::::::::::F   O:::::O     O:::::O  SS::::::SSSSS    
//0:::::0 000 0:::::0    x::::::::::x    U:::::D     D:::::U   F:::::::::::::::F   O:::::O     O:::::O    SSS::::::::SS  
//0:::::0     0:::::0     x::::::::x     U:::::D     D:::::U   F::::::FFFFFFFFFF   O:::::O     O:::::O       SSSSSS::::S 
//0:::::0     0:::::0     x::::::::x     U:::::D     D:::::U   F:::::F             O:::::O     O:::::O            S:::::S
//0::::::0   0::::::0    x::::::::::x    U::::::U   U::::::U   F:::::F             O::::::O   O::::::O            S:::::S
//0:::::::000:::::::0   x:::::xx:::::x   U:::::::UUU:::::::U FF:::::::FF           O:::::::OOO:::::::OSSSSSSS     S:::::S
//00:::::::::::::00   x:::::x  x:::::x   UU:::::::::::::UU  F::::::::FF            OO:::::::::::::OO S::::::SSSSSS:::::S
// 00:::::::::00    x:::::x    x:::::x    UU:::::::::UU    F::::::::FF              OO:::::::::OO   S:::::::::::::::SS 
//  000000000     xxxxxxx      xxxxxxx     UUUUUUUUU      FFFFFFFFFFF                OOOOOOOOO      SSSSSSSSSSSSSSS   

// 10,000 Fully Generated on Chain Animated UFO NFTs @0xUFOs     

pragma solidity ^0.8.13;

interface IUFOIdentifier {
    function tokenURI(uint256 tokenId, uint256 seed) external view returns (string memory);
}
// 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: contracts/lib/ERC721Enumerable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.19;

import "./ERC721.sol";
import "@openzeppelin/contracts/token/ERC721/extensions/IERC721Enumerable.sol";

abstract contract ERC721Enumerable is ERC721, IERC721Enumerable {
    function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165, ERC721) returns (bool) {
        return interfaceId == type(IERC721Enumerable).interfaceId || super.supportsInterface(interfaceId);
    }

    function totalSupply() public view virtual override returns (uint256) {
        uint256 count;
        for (uint256 i; i < _owners.length;) {
            if (_owners[i] != address(0)) {
                unchecked {
                    ++count;
                }
            }

            unchecked {
                ++i;
            }
        }

        return count;
    }

    function tokenByIndex(uint256 index) public view virtual override returns (uint256 tokenId) {
        require(index < _owners.length, "ERC721Enumerable: global index out of bounds");
        return index;
    }

    function tokenOfOwnerByIndex(address owner, uint256 index) public view virtual override returns (uint256 tokenId) {
        require(index < balanceOf(owner), "ERC721Enumerable: owner index out of bounds");

        uint256 count;
        for(uint256 i; i < _owners.length;){
            if(owner == _owners[i]) {
                if(count == index) return i;
                else {
                    unchecked {
                        ++count;
                    }
                }
            }

            unchecked {
                ++i;
            }
        }

        revert("ERC721Enumerable: owner index out of bounds");
    }
}
// File: @openzeppelin/contracts/token/ERC721/extensions/IERC721Enumerable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC721/extensions/IERC721Enumerable.sol)

pragma solidity ^0.8.0;

import "../IERC721.sol";

/**
 * @title ERC-721 Non-Fungible Token Standard, optional enumeration extension
 * @dev See https://eips.ethereum.org/EIPS/eip-721
 */
interface IERC721Enumerable is IERC721 {
    /**
     * @dev Returns the total amount of tokens stored by the contract.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns a token ID owned by `owner` at a given `index` of its token list.
     * Use along with {balanceOf} to enumerate all of ``owner``'s tokens.
     */
    function tokenOfOwnerByIndex(address owner, uint256 index) external view returns (uint256);

    /**
     * @dev Returns a token ID at a given `index` of all the tokens stored by the contract.
     * Use along with {totalSupply} to enumerate all tokens.
     */
    function tokenByIndex(uint256 index) external view returns (uint256);
}

// File: contracts/lib/ERC721.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.19;

import "@openzeppelin/contracts/token/ERC721/IERC721.sol";
import "@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol";
import "@openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol";
import "@openzeppelin/contracts/utils/Context.sol";
import "@openzeppelin/contracts/utils/Strings.sol";
import "@openzeppelin/contracts/utils/introspection/ERC165.sol";
import "./Address.sol";

abstract contract ERC721 is Context, ERC165, IERC721, IERC721Metadata {
    using Address for address;
    using Strings for uint256;

    string private _name;
    string private _symbol;

    address[] internal _owners;

    mapping(uint256 => address) private _tokenApprovals;
    mapping(address => mapping(address => bool)) private _operatorApprovals;

    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
        return interfaceId == type(IERC721).interfaceId
        || interfaceId == type(IERC721Metadata).interfaceId
        || super.supportsInterface(interfaceId);
    }

    function balanceOf(address owner) public view virtual override returns (uint256) {
        require(owner != address(0), "ERC721: address zero is not a valid owner");

        uint256 count;
        for (uint256 i; i < _owners.length;) {
            if (owner == _owners[i]) {
                unchecked {
                    ++count;
                }
            }
            unchecked {
                ++i;
            }
        }
        return count;
    }

    function ownerOf(uint256 tokenId) public view virtual override returns (address) {
        address owner = _owners[tokenId];
        require(owner != address(0), "ERC721: invalid token ID");
        return owner;
    }

    function name() public view virtual override returns (string memory) {
        return _name;
    }

    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    function approve(address to, uint256 tokenId) public virtual override {
        address owner = ERC721.ownerOf(tokenId);
        require(to != owner, "ERC721: approval to current owner");

        require(
            _msgSender() == owner || isApprovedForAll(owner, _msgSender()),
            "ERC721: approve caller is not owner nor approved for all"
        );

        _approve(to, tokenId);
    }

    function getApproved(uint256 tokenId) public view virtual override returns (address) {
        require(_exists(tokenId), "ERC721: invalid token ID");

        return _tokenApprovals[tokenId];
    }

    function setApprovalForAll(address operator, bool approved) public virtual override {
        require(_msgSender() != operator, "ERC721: approve to caller");
        _operatorApprovals[_msgSender()][operator] = approved;
        emit ApprovalForAll(_msgSender(), operator, approved);
    }

    function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
        return _operatorApprovals[owner][operator];
    }

    function transferFrom(address from, address to, uint256 tokenId) public virtual override {
        require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner or approved");
        _transfer(from, to, tokenId);
    }

    function safeTransferFrom(address from, address to, uint256 tokenId) public virtual override {
        safeTransferFrom(from, to, tokenId, "");
    }

    function safeTransferFrom(address from, address to, uint256 tokenId, bytes memory data) public virtual override {
        require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner or approved");
        _safeTransfer(from, to, tokenId, data);
    }

    function _safeTransfer(address from, address to, uint256 tokenId, bytes memory data) internal virtual {
        _transfer(from, to, tokenId);
        require(_checkOnERC721Received(from, to, tokenId, data), "ERC721: transfer to non ERC721Receiver implementer");
    }

    function _exists(uint256 tokenId) internal view virtual returns (bool) {
        return tokenId < _owners.length && _owners[tokenId] != address(0);
    }

    function _isApprovedOrOwner(address spender, uint256 tokenId) internal view virtual returns (bool) {
        address owner = ERC721.ownerOf(tokenId);
        return (spender == owner || isApprovedForAll(owner, spender) || getApproved(tokenId) == spender);
    }

    function _mint(address to, uint256 tokenId) internal virtual {
        require(!_exists(tokenId), "ERC721: token already minted");

        _owners.push(to);

        emit Transfer(address(0), to, tokenId);
    }

    function _burn(uint256 tokenId) internal virtual {
        address owner = ERC721.ownerOf(tokenId);

        delete _tokenApprovals[tokenId];
        delete _owners[tokenId];

        emit Transfer(owner, address(0), tokenId);
    }

    function _transfer(address from, address to, uint256 tokenId) internal virtual {
        require(ERC721.ownerOf(tokenId) == from, "ERC721: transfer from incorrect owner");
        require(to != address(0), "ERC721: transfer to the zero address");

        // Clear approvals from the previous owner
        delete _tokenApprovals[tokenId];
        _owners[tokenId] = to;

        emit Transfer(from, to, tokenId);
    }

    function _approve(address to, uint256 tokenId) internal virtual {
        _tokenApprovals[tokenId] = to;
        emit Approval(ERC721.ownerOf(tokenId), to, tokenId);
    }

    function _checkOnERC721Received(address from, address to, uint256 tokenId, bytes memory data) private returns (bool) {
        if (to.isContract()) {
            try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, data) returns (bytes4 retval) {
                return retval == IERC721Receiver.onERC721Received.selector;
            } catch (bytes memory reason) {
                if (reason.length == 0) {
                    revert("ERC721: transfer to non ERC721Receiver implementer");
                } else {
                    assembly {
                        revert(add(32, reason), mload(reason))
                    }
                }
            }
        }

        return true;
    }
}
// File: contracts/extension/interface/IRoyalty.sol



// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

import "../../eip/interface/IERC2981.sol";

/**
 *  Thirdweb's `Royalty` is a contract extension to be used with any base contract. It exposes functions for setting and reading
 *  the recipient of royalty fee and the royalty fee basis points, and lets the inheriting contract perform conditional logic
 *  that uses information about royalty fees, if desired.
 *
 *  The `Royalty` contract is ERC2981 compliant.
 */

interface IRoyalty is IERC2981 {
    struct RoyaltyInfo {
        address recipient;
        uint256 bps;
    }

    /// @dev Returns the royalty recipient and fee bps.
    function getDefaultRoyaltyInfo() external view returns (address, uint16);

    /// @dev Lets a module admin update the royalty bps and recipient.
    function setDefaultRoyaltyInfo(address _royaltyRecipient, uint256 _royaltyBps) external;

    /// @dev Lets a module admin set the royalty recipient for a particular token Id.
    function setRoyaltyInfoForToken(
        uint256 tokenId,
        address recipient,
        uint256 bps
    ) external;

    /// @dev Returns the royalty recipient for a particular token Id.
    function getRoyaltyInfoForToken(uint256 tokenId) external view returns (address, uint16);

    /// @dev Emitted when royalty info is updated.
    event DefaultRoyalty(address indexed newRoyaltyRecipient, uint256 newRoyaltyBps);

    /// @dev Emitted when royalty recipient for tokenId is set
    event RoyaltyForToken(uint256 indexed tokenId, address indexed royaltyRecipient, uint256 royaltyBps);
}

// File: contracts/extension/OperatorFilterer.sol



// SPDX-License-Identifier: Apache 2.0
pragma solidity ^0.8.0;

/// @author thirdweb

import "./interface/IOperatorFilterRegistry.sol";
import "./OperatorFilterToggle.sol";

/**
 * @title  OperatorFilterer
 * @notice Abstract contract whose constructor automatically registers and optionally subscribes to or copies another
 *         registrant's entries in the OperatorFilterRegistry.
 * @dev    This smart contract is meant to be inherited by token contracts so they can use the following:
 *         - `onlyAllowedOperator` modifier for `transferFrom` and `safeTransferFrom` methods.
 *         - `onlyAllowedOperatorApproval` modifier for `approve` and `setApprovalForAll` methods.
 */

abstract contract OperatorFilterer is OperatorFilterToggle {
    error OperatorNotAllowed(address operator);

    IOperatorFilterRegistry public constant OPERATOR_FILTER_REGISTRY =
        IOperatorFilterRegistry(0x000000000000AAeB6D7670E522A718067333cd4E);

    constructor(address subscriptionOrRegistrantToCopy, bool subscribe) {
        // If an inheriting token contract is deployed to a network without the registry deployed, the modifier
        // will not revert, but the contract will need to be registered with the registry once it is deployed in
        // order for the modifier to filter addresses.
        if (address(OPERATOR_FILTER_REGISTRY).code.length > 0) {
            if (subscribe) {
                OPERATOR_FILTER_REGISTRY.registerAndSubscribe(address(this), subscriptionOrRegistrantToCopy);
            } else {
                if (subscriptionOrRegistrantToCopy != address(0)) {
                    OPERATOR_FILTER_REGISTRY.registerAndCopyEntries(address(this), subscriptionOrRegistrantToCopy);
                } else {
                    OPERATOR_FILTER_REGISTRY.register(address(this));
                }
            }
        }
    }

    modifier onlyAllowedOperator(address from) virtual {
        // Allow spending tokens from addresses with balance
        // Note that this still allows listings and marketplaces with escrow to transfer tokens if transferred
        // from an EOA.
        if (from != msg.sender) {
            _checkFilterOperator(msg.sender);
        }
        _;
    }

    modifier onlyAllowedOperatorApproval(address operator) virtual {
        _checkFilterOperator(operator);
        _;
    }

    function _checkFilterOperator(address operator) internal view virtual {
        // Check registry code length to facilitate testing in environments without a deployed registry.
        if (operatorRestriction) {
            if (address(OPERATOR_FILTER_REGISTRY).code.length > 0) {
                if (!OPERATOR_FILTER_REGISTRY.isOperatorAllowed(address(this), operator)) {
                    revert OperatorNotAllowed(operator);
                }
            }
        }
    }
}

// File: contracts/extension/interface/IContractMetadata.sol



// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

/**
 *  Thirdweb's `ContractMetadata` is a contract extension for any base contracts. It lets you set a metadata URI
 *  for you contract.
 *
 *  Additionally, `ContractMetadata` is necessary for NFT contracts that want royalties to get distributed on OpenSea.
 */

interface IContractMetadata {
    /// @dev Returns the metadata URI of the contract.
    function contractURI() external view returns (string memory);

    /**
     *  @dev Sets contract URI for the storefront-level metadata of the contract.
     *       Only module admin can call this function.
     */
    function setContractURI(string calldata _uri) external;

    /// @dev Emitted when the contract URI is updated.
    event ContractURIUpdated(string prevURI, string newURI);
}

// 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: contracts/lib/Address.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.19;

library Address {
    function isContract(address account) internal view returns (bool) {
        uint size;
        assembly {
            size := extcodesize(account)
        }
        return size > 0;
    }
}
// File: @openzeppelin/contracts/utils/introspection/ERC165.sol



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

pragma solidity ^0.8.0;

import "./IERC165.sol";

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

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



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

pragma solidity ^0.8.0;

import "./math/Math.sol";

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

    /**
     * @dev Converts a `uint256` to its ASCII `string` decimal representation.
     */
    function toString(uint256 value) internal pure returns (string memory) {
        unchecked {
            uint256 length = Math.log10(value) + 1;
            string memory buffer = new string(length);
            uint256 ptr;
            /// @solidity memory-safe-assembly
            assembly {
                ptr := add(buffer, add(32, length))
            }
            while (true) {
                ptr--;
                /// @solidity memory-safe-assembly
                assembly {
                    mstore8(ptr, byte(mod(value, 10), _SYMBOLS))
                }
                value /= 10;
                if (value == 0) break;
            }
            return buffer;
        }
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        unchecked {
            return toHexString(value, Math.log256(value) + 1);
        }
    }

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

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

// File: @openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/IERC721Metadata.sol)

pragma solidity ^0.8.0;

import "../IERC721.sol";

/**
 * @title ERC-721 Non-Fungible Token Standard, optional metadata extension
 * @dev See https://eips.ethereum.org/EIPS/eip-721
 */
interface IERC721Metadata is IERC721 {
    /**
     * @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);
}

// File: @openzeppelin/contracts/token/ERC721/IERC721Receiver.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC721/IERC721Receiver.sol)

pragma solidity ^0.8.0;

/**
 * @title ERC721 token receiver interface
 * @dev Interface for any contract that wants to support safeTransfers
 * from ERC721 asset contracts.
 */
interface IERC721Receiver {
    /**
     * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
     * by `operator` from `from`, this function is called.
     *
     * It must return its Solidity selector to confirm the token transfer.
     * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
     *
     * The selector can be obtained in Solidity with `IERC721Receiver.onERC721Received.selector`.
     */
    function onERC721Received(
        address operator,
        address from,
        uint256 tokenId,
        bytes calldata data
    ) external returns (bytes4);
}

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC721/IERC721.sol)

pragma solidity ^0.8.0;

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

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

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

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

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

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

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

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

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

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

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

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

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

// File: contracts/eip/interface/IERC2981.sol



// SPDX-License-Identifier: Apache 2.0
pragma solidity ^0.8.0;


/**
 * @dev Interface for the NFT Royalty Standard.
 *
 * A standardized way to retrieve royalty payment information for non-fungible tokens (NFTs) to enable universal
 * support for royalty payments across all NFT marketplaces and ecosystem participants.
 *
 * _Available since v4.5._
 */
interface IERC2981 {
    /**
     * @dev Returns how much royalty is owed and to whom, based on a sale price that may be denominated in any unit of
     * exchange. The royalty amount is denominated and should be payed in that same unit of exchange.
     */
    function royaltyInfo(uint256 tokenId, uint256 salePrice)
        external
        view
        returns (address receiver, uint256 royaltyAmount);
}

// File: contracts/extension/OperatorFilterToggle.sol



// SPDX-License-Identifier: Apache 2.0
pragma solidity ^0.8.0;

/// @author thirdweb

import "./interface/IOperatorFilterToggle.sol";

abstract contract OperatorFilterToggle is IOperatorFilterToggle {
    bool public operatorRestriction;

    function setOperatorRestriction(bool _restriction) external {
        require(_canSetOperatorRestriction(), "Not authorized to set operator restriction.");
        _setOperatorRestriction(_restriction);
    }

    function _setOperatorRestriction(bool _restriction) internal {
        operatorRestriction = _restriction;
        emit OperatorRestriction(_restriction);
    }

    function _canSetOperatorRestriction() internal virtual returns (bool);
}

// File: contracts/extension/interface/IOperatorFilterRegistry.sol



// SPDX-License-Identifier: Apache 2.0
pragma solidity ^0.8.0;

/// @author thirdweb

interface IOperatorFilterRegistry {
    function isOperatorAllowed(address registrant, address operator) external view returns (bool);

    function register(address registrant) external;

    function registerAndSubscribe(address registrant, address subscription) external;

    function registerAndCopyEntries(address registrant, address registrantToCopy) external;

    function unregister(address addr) external;

    function updateOperator(
        address registrant,
        address operator,
        bool filtered
    ) external;

    function updateOperators(
        address registrant,
        address[] calldata operators,
        bool filtered
    ) external;

    function updateCodeHash(
        address registrant,
        bytes32 codehash,
        bool filtered
    ) external;

    function updateCodeHashes(
        address registrant,
        bytes32[] calldata codeHashes,
        bool filtered
    ) external;

    function subscribe(address registrant, address registrantToSubscribe) external;

    function unsubscribe(address registrant, bool copyExistingEntries) external;

    function subscriptionOf(address addr) external returns (address registrant);

    function subscribers(address registrant) external returns (address[] memory);

    function subscriberAt(address registrant, uint256 index) external returns (address);

    function copyEntriesOf(address registrant, address registrantToCopy) external;

    function isOperatorFiltered(address registrant, address operator) external returns (bool);

    function isCodeHashOfFiltered(address registrant, address operatorWithCode) external returns (bool);

    function isCodeHashFiltered(address registrant, bytes32 codeHash) external returns (bool);

    function filteredOperators(address addr) external returns (address[] memory);

    function filteredCodeHashes(address addr) external returns (bytes32[] memory);

    function filteredOperatorAt(address registrant, uint256 index) external returns (address);

    function filteredCodeHashAt(address registrant, uint256 index) external returns (bytes32);

    function isRegistered(address addr) external returns (bool);

    function codeHashOf(address addr) external returns (bytes32);
}

// File: contracts/extension/interface/IOperatorFilterToggle.sol



// SPDX-License-Identifier: Apache 2.0
pragma solidity ^0.8.0;

/// @author thirdweb

interface IOperatorFilterToggle {
    event OperatorRestriction(bool restriction);

    function operatorRestriction() external view returns (bool);

    function setOperatorRestriction(bool restriction) external;
}

// 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: @openzeppelin/contracts/utils/math/Math.sol



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

pragma solidity ^0.8.0;

/**
 * @dev Standard math utilities missing in the Solidity language.
 */
library Math {
    enum Rounding {
        Down, // Toward negative infinity
        Up, // Toward infinity
        Zero // Toward zero
    }

    /**
     * @dev Returns the largest of two numbers.
     */
    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a > b ? a : b;
    }

    /**
     * @dev Returns the smallest of two numbers.
     */
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }

    /**
     * @dev Returns the average of two numbers. The result is rounded towards
     * zero.
     */
    function average(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b) / 2 can overflow.
        return (a & b) + (a ^ b) / 2;
    }

    /**
     * @dev Returns the ceiling of the division of two numbers.
     *
     * This differs from standard division with `/` in that it rounds up instead
     * of rounding down.
     */
    function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b - 1) / b can overflow on addition, so we distribute.
        return a == 0 ? 0 : (a - 1) / b + 1;
    }

    /**
     * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
     * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
     * with further edits by Uniswap Labs also under MIT license.
     */
    function mulDiv(
        uint256 x,
        uint256 y,
        uint256 denominator
    ) internal pure returns (uint256 result) {
        unchecked {
            // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
            // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
            // variables such that product = prod1 * 2^256 + prod0.
            uint256 prod0; // Least significant 256 bits of the product
            uint256 prod1; // Most significant 256 bits of the product
            assembly {
                let mm := mulmod(x, y, not(0))
                prod0 := mul(x, y)
                prod1 := sub(sub(mm, prod0), lt(mm, prod0))
            }

            // Handle non-overflow cases, 256 by 256 division.
            if (prod1 == 0) {
                return prod0 / denominator;
            }

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

            ///////////////////////////////////////////////
            // 512 by 256 division.
            ///////////////////////////////////////////////

            // Make division exact by subtracting the remainder from [prod1 prod0].
            uint256 remainder;
            assembly {
                // Compute remainder using mulmod.
                remainder := mulmod(x, y, denominator)

                // Subtract 256 bit number from 512 bit number.
                prod1 := sub(prod1, gt(remainder, prod0))
                prod0 := sub(prod0, remainder)
            }

            // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
            // See https://cs.stackexchange.com/q/138556/92363.

            // Does not overflow because the denominator cannot be zero at this stage in the function.
            uint256 twos = denominator & (~denominator + 1);
            assembly {
                // Divide denominator by twos.
                denominator := div(denominator, twos)

                // Divide [prod1 prod0] by twos.
                prod0 := div(prod0, twos)

                // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                twos := add(div(sub(0, twos), twos), 1)
            }

            // Shift in bits from prod1 into prod0.
            prod0 |= prod1 * twos;

            // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
            // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
            // four bits. That is, denominator * inv = 1 mod 2^4.
            uint256 inverse = (3 * denominator) ^ 2;

            // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
            // in modular arithmetic, doubling the correct bits in each step.
            inverse *= 2 - denominator * inverse; // inverse mod 2^8
            inverse *= 2 - denominator * inverse; // inverse mod 2^16
            inverse *= 2 - denominator * inverse; // inverse mod 2^32
            inverse *= 2 - denominator * inverse; // inverse mod 2^64
            inverse *= 2 - denominator * inverse; // inverse mod 2^128
            inverse *= 2 - denominator * inverse; // inverse mod 2^256

            // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
            // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
            // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
            // is no longer required.
            result = prod0 * inverse;
            return result;
        }
    }

    /**
     * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
     */
    function mulDiv(
        uint256 x,
        uint256 y,
        uint256 denominator,
        Rounding rounding
    ) internal pure returns (uint256) {
        uint256 result = mulDiv(x, y, denominator);
        if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
            result += 1;
        }
        return result;
    }

    /**
     * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
     *
     * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
     */
    function sqrt(uint256 a) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }

        // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
        //
        // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
        // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
        //
        // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
        // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
        // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
        //
        // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
        uint256 result = 1 << (log2(a) >> 1);

        // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
        // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
        // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
        // into the expected uint128 result.
        unchecked {
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            return min(result, a / result);
        }
    }

    /**
     * @notice Calculates sqrt(a), following the selected rounding direction.
     */
    function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = sqrt(a);
            return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 2, rounded down, of a positive value.
     * Returns 0 if given 0.
     */
    function log2(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 128;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 64;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 32;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 16;
            }
            if (value >> 8 > 0) {
                value >>= 8;
                result += 8;
            }
            if (value >> 4 > 0) {
                value >>= 4;
                result += 4;
            }
            if (value >> 2 > 0) {
                value >>= 2;
                result += 2;
            }
            if (value >> 1 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 2, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log2(value);
            return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 10, rounded down, of a positive value.
     * Returns 0 if given 0.
     */
    function log10(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >= 10**64) {
                value /= 10**64;
                result += 64;
            }
            if (value >= 10**32) {
                value /= 10**32;
                result += 32;
            }
            if (value >= 10**16) {
                value /= 10**16;
                result += 16;
            }
            if (value >= 10**8) {
                value /= 10**8;
                result += 8;
            }
            if (value >= 10**4) {
                value /= 10**4;
                result += 4;
            }
            if (value >= 10**2) {
                value /= 10**2;
                result += 2;
            }
            if (value >= 10**1) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log10(value);
            return result + (rounding == Rounding.Up && 10**result < value ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 256, rounded down, of a positive value.
     * Returns 0 if given 0.
     *
     * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
     */
    function log256(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 16;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 8;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 4;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 2;
            }
            if (value >> 8 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log256(value);
            return result + (rounding == Rounding.Up && 1 << (result * 8) < value ? 1 : 0);
        }
    }
}