// File: contracts/xr/ChainRunnersBurnEvent.sol



import "@openzeppelin/contracts/access/Ownable.sol";
import "../ChainRunnersXR.sol";
import "../ChainRunnersItems.sol";
import "../ChainRunners.sol";

contract ChainRunnersBurnEvent is Ownable, IERC721Receiver {
    address private _xrContractAddress;
    uint256 private _eventStartTimestamp;
    uint256 private _lastMintedXrTokenId;
    uint256[] private _availableXrTokenIds;
    uint256 private _maxRerollsPerTransaction;

    error TokenDoesNotExist();
    error NotTokenOwner();
    error CannotBurnRerolledTokens();
    error BurnEventHasNotStarted();
    error MaxSupplyExceeded();
    error IncorrectNumberOfTokens();

    event RerolledXrTokens(uint256[] burnedTokenIds, uint256[] mintedTokenIds);

    constructor(address xrContractAddress) {
        _xrContractAddress = xrContractAddress;
        _maxRerollsPerTransaction = 10;
    }

    // MODIFIERS
    modifier onlyWhenEventActive() {
        if (_eventStartTimestamp == 0 || block.timestamp < _eventStartTimestamp || _maxRerollsPerTransaction == 0)
            revert BurnEventHasNotStarted();
        _;
    }

    // REROLL - MANAGE
    function burnAndRerollXrTokens(uint256[] memory xrTokenIds) public onlyWhenEventActive returns (uint256[] memory) {
        if (xrTokenIds.length == 0 || xrTokenIds.length > _maxRerollsPerTransaction) revert IncorrectNumberOfTokens();
        _burnXrTokens(xrTokenIds);
        uint256[] memory mintedTokenIds = _mintXrTokens(xrTokenIds.length);
        emit RerolledXrTokens(xrTokenIds, mintedTokenIds);
        return mintedTokenIds;
    }

    // REROLL - VIEW
    function getAvailableXrTokenIds() public view returns (uint256[] memory) {
        return _availableXrTokenIds;
    }

    function getNumberOfAvailableXrTokens() public view returns (uint256) {
        return _availableXrTokenIds.length;
    }

    function getTokenIdAtIndex(uint256 i) public view returns (uint256) {
        return _availableXrTokenIds[i];
    }

    function getLastMintedXrTokenId() public view returns (uint256) {
        return _lastMintedXrTokenId;
    }

    // INTERNAL - MANAGE
    function _burnXrTokens(uint256[] memory xrTokenIds) internal {
        ChainRunnersXR xrContract = ChainRunnersXR(_xrContractAddress);
        for (uint256 i; i < xrTokenIds.length; i++) {
            if (xrTokenIds[i] > _lastMintedXrTokenId) revert CannotBurnRerolledTokens();
            if (xrContract.ownerOf(xrTokenIds[i]) != _msgSender()) revert NotTokenOwner();
            xrContract.burn(xrTokenIds[i]);
        }
    }

    function _mintXrTokens(uint256 quantity) internal returns (uint256[] memory mintedXrTokenIds) {
        ChainRunnersXR xrContract = ChainRunnersXR(_xrContractAddress);
        if (quantity > _availableXrTokenIds.length) revert MaxSupplyExceeded();
        mintedXrTokenIds = new uint256[](quantity);
        for (uint256 i; i < quantity; i++) {
            uint256 tokenIdIndex = randomNumber(_msgSender(), _availableXrTokenIds.length) %
            _availableXrTokenIds.length;
            uint256 tokenId = _availableXrTokenIds[tokenIdIndex];
            _availableXrTokenIds[tokenIdIndex] = _availableXrTokenIds[_availableXrTokenIds.length - 1];
            _availableXrTokenIds.pop();
            xrContract.safeTransferFrom(address(this), _msgSender(), tokenId);
            mintedXrTokenIds[i] = tokenId;
        }
        return mintedXrTokenIds;
    }

    // INTERNAL - VIEW
    function randomNumber(address to, uint256 remainingSupply) internal view returns (uint256) {
        return
        uint256(
            keccak256(
                abi.encode(
                    to,
                    tx.gasprice,
                    block.number,
                    block.timestamp,
                    block.difficulty,
                    blockhash(block.number - 1),
                    address(this),
                    remainingSupply
                )
            )
        );
    }

    // ADMIN - MANAGE
    function setXrContractAddress(address xrContractAddress) public onlyOwner {
        _xrContractAddress = xrContractAddress;
    }

    function setEventStartTimestamp(uint256 eventStartTimestamp) public onlyOwner {
        _eventStartTimestamp = eventStartTimestamp;
    }

    function setLastMintedXrTokenId(uint256 lastMintedXrTokenId) public onlyOwner {
        _lastMintedXrTokenId = lastMintedXrTokenId;
    }

    function setMaxRerollsPerTransaction(uint256 maxRerollsPerTransaction) public onlyOwner {
        _maxRerollsPerTransaction = maxRerollsPerTransaction;
    }

    function devMintXr(uint256 quantity) public onlyOwner {
        ChainRunnersXR xrContract = ChainRunnersXR(_xrContractAddress);
        xrContract.mintDev(quantity);
    }

    function transferXrContractOwnership(address newOwner) public onlyOwner {
        Ownable xrContract = Ownable(_xrContractAddress);
        xrContract.transferOwnership(newOwner);
    }

    function emergencyTransferXrTokens(address to, uint256[] memory tokenIds) public onlyOwner {
        ChainRunnersXR xrContract = ChainRunnersXR(_xrContractAddress);
        for (uint256 i; i < tokenIds.length; i++) {
            xrContract.safeTransferFrom(address(this), to, tokenIds[i]);
        }
    }

    function emergencyDeleteTokenIndex(uint256 i) public onlyOwner {
        _availableXrTokenIds[i] = _availableXrTokenIds[_availableXrTokenIds.length - 1];
        _availableXrTokenIds.pop();
    }

    // ADMIN -READ
    function xrContractAddress() public view returns (address) {
        return _xrContractAddress;
    }

    function eventStartTimestamp() public view returns (uint256) {
        return _eventStartTimestamp;
    }

    function lastMintedXrTokenId() public view returns (uint256) {
        return _lastMintedXrTokenId;
    }

    function maxRerollsPerTransaction() public view returns (uint256) {
        return _maxRerollsPerTransaction;
    }

    /**
     * @dev See {IERC1155Receiver-onERC721Received}.
     */
    function onERC721Received(
        address operator,
        address from,
        uint256 tokenId,
        bytes calldata data
    ) external override returns (bytes4) {
        if (operator == address(this)) {
            _availableXrTokenIds.push(tokenId);
        }
        return this.onERC721Received.selector;
    }
}

// File: contracts/ChainRunnersXR.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.4;

import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import "@openzeppelin/contracts/utils/cryptography/MerkleProof.sol";
import "./core/ERC721AClaimable.sol";
import "./interfaces/IChainRunnersRenderer.sol";
import "./interfaces/IChainRunners.sol";

/*
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*/

contract ChainRunnersXR is Ownable, ERC721AClaimable, ReentrancyGuard {

    address public genesisContractAddress;
    address public xrRendererContractAddress;

    uint256 public immutable amountForDevs;
    uint256 public immutable mintCollectionSize;

    uint256 public numAvailableTokens = 10000;
    mapping(uint => uint) private _availableTokens;

    mapping(uint256 => uint256) tokenIdToContentIdMapping;

    uint256 public publicSaleStartTimestamp;
    uint256 public allowlistStartTimestamp;
    uint256 public claimStartTimestamp;

    mapping(address => uint256) public allowlist;
    bytes32 private allowlistMerkleRoot;

    uint256[40] claimedBitMap;

    uint256 public constant MAX_PER_ADDRESS_DURING_ALLOWLIST_MINT = 1;
    uint256 public constant MAX_PER_TRANSACTION_DURING_PUBLIC = 5;
    uint256 public constant PRICE_PER_TOKEN = 0.1 ether;
    uint256 public constant MAX_BATCH_SIZE = 5;

    uint256 revealSeed;

    uint256 public burningStartTimestamp;

    constructor(
        uint256 mintCollectionSize_,
        uint256 amountForDevs_,
        address genesisContractAddress_,
        address xrRendererContractAddress_
    ) ERC721AClaimable("Chain Runners XR", "XR") {
        mintCollectionSize = mintCollectionSize_;
        amountForDevs = amountForDevs_;
        genesisContractAddress = genesisContractAddress_;
        xrRendererContractAddress = xrRendererContractAddress_;
    }

    modifier callerIsUser() {
        require(tx.origin == msg.sender, "the caller is another contract");
        _;
    }

    // SALE CONFIG FUNCTIONS
    function setAllowlistSaleStartTimestamp(uint256 _allowlistStartTimestamp) external onlyOwner {
        allowlistStartTimestamp = _allowlistStartTimestamp;
    }

    function setPublicSaleStartTimestamp(uint256 _publicSaleStartTimestamp) external onlyOwner {
        publicSaleStartTimestamp = _publicSaleStartTimestamp;
    }

    function setClaimStartTimestamp(uint256 _claimStartTimestamp) external onlyOwner {
        claimStartTimestamp = _claimStartTimestamp;
    }

    function isPublicSaleActive() public view returns (bool) {
        return
        publicSaleStartTimestamp != 0 &&
        block.timestamp >= publicSaleStartTimestamp;
    }

    function isAllowlistSaleActive() public view returns (bool) {
        return
        allowlistStartTimestamp != 0 &&
        block.timestamp >= allowlistStartTimestamp;
    }

    function isClaimActive() public view returns (bool) {
        return
        claimStartTimestamp != 0 &&
        block.timestamp >= claimStartTimestamp;
    }

    function setAllowlistMerkleRoot(bytes32 _root) external onlyOwner {
        allowlistMerkleRoot = _root;
    }

    function setXRRenderingContractAddress(address _xrRenderingContractAddress) public onlyOwner {
        xrRendererContractAddress = _xrRenderingContractAddress;
    }

    function reveal(uint256 _revealSeed) external onlyOwner {
        revealSeed = _revealSeed;
    }

    // MINTING FUNCTIONS
    function mintDev(uint256 _quantity) external onlyOwner {
        require(
            _totalMinted() + _quantity <= mintCollectionSize,
            "too many already minted before dev mint"
        );
        require(
            _quantity % MAX_BATCH_SIZE == 0,
            "can only mint a multiple of the maxBatchSize"
        );
        require(_quantity <= amountForDevs, "quantity is too high");

        uint256 numChunks = _quantity / MAX_BATCH_SIZE;
        for (uint256 i = 0; i < numChunks; i++) {
            _mintRandom(msg.sender, MAX_BATCH_SIZE);
        }
    }

    function mintAllowlist(uint256 _quantity, bytes32[] calldata _merkleProof) external payable callerIsUser returns (uint256) {
        require(isAllowlistSaleActive(), "allowlist sale has not begun yet");
        require(MerkleProof.verify(_merkleProof, allowlistMerkleRoot, keccak256(abi.encodePacked(msg.sender))), "not on allowlist");
        require(allowlist[msg.sender] + _quantity <= MAX_PER_ADDRESS_DURING_ALLOWLIST_MINT, "not eligible for allowlist mint");
        require(_totalMinted() + _quantity <= (mintCollectionSize - amountForDevs), "reached max supply");

        uint256 totalCost = uint256(PRICE_PER_TOKEN * _quantity);
        unchecked {
            allowlist[msg.sender] += _quantity;
        }
        _mintRandom(msg.sender, _quantity);
        refundIfOver(totalCost);
        return _currentMintIndex - _quantity;
    }

    function mintPublic(uint256 _quantity) external payable callerIsUser returns (uint256) {
        require(isPublicSaleActive(), "public sale has not begun yet");
        require(_totalMinted() + _quantity <= (mintCollectionSize - amountForDevs), "reached max supply");
        require(_quantity <= MAX_PER_TRANSACTION_DURING_PUBLIC, "quantity too high");

        _mintRandom(msg.sender, _quantity);
        refundIfOver(PRICE_PER_TOKEN * _quantity);
        return _currentMintIndex - _quantity;
    }

    /**
    * Mint `_numToMint` tokens. Use Fisher Yates to draw a uniformly random
    * contentId to associate with each tokenId.
    */
    function _mintRandom(address _to, uint _numToMint) internal {
        uint updatedNumAvailableTokens = numAvailableTokens;
        for (uint256 i; i < _numToMint; i++) {
            uint256 contentId = getRandomAvailableContentId(_to, updatedNumAvailableTokens--);
            tokenIdToContentIdMapping[_currentMintIndex+i] = contentId;
        }
        _safeMint(_to, _numToMint);
        numAvailableTokens = updatedNumAvailableTokens;
    }

    function getRandomAvailableContentId(address _to, uint _updatedNumAvailableTokens)
    internal
    returns (uint256)
    {
        uint256 randomNum = randomNumber(_to, _updatedNumAvailableTokens);
        uint256 randomIndex = randomNum % _updatedNumAvailableTokens;
        return getAvailableTokenAtIndex(randomIndex, _updatedNumAvailableTokens);
    }

    function randomNumber(address _to, uint _updatedNumAvailableTokens) internal view returns (uint256) {
        return uint256(
            keccak256(
                abi.encode(
                    _to,
                    tx.gasprice,
                    block.number,
                    block.timestamp,
                    block.difficulty,
                    blockhash(block.number - 1),
                    address(this),
                    _updatedNumAvailableTokens
                )
            )
        );
    }

    // Implements https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle.  Code from https://github.com/erc721r/ERC721R/blob/main/contracts/ERC721R.sol
    function getAvailableTokenAtIndex(uint256 _indexToUse, uint _updatedNumAvailableTokens)
    internal
    returns (uint256)
    {
        uint256 valAtIndex = _availableTokens[_indexToUse];
        uint256 result;
        if (valAtIndex == 0) {
            // This means the index itself is still an available token
            result = _indexToUse;
        } else {
            // This means the index itself is not an available token, but the val at that index is.
            result = valAtIndex;
        }

        uint256 lastIndex = _updatedNumAvailableTokens - 1;
        if (_indexToUse != lastIndex) {
            // Replace the value at indexToUse, now that it's been used.
            // Replace it with the data from the last index in the array, since we are going to decrease the array size afterwards.
            uint256 lastValInArray = _availableTokens[lastIndex];
            if (lastValInArray == 0) {
                // This means the index itself is still an available token
                _availableTokens[_indexToUse] = lastIndex;
            } else {
                // This means the index itself is not an available token, but the val at that index is.
                _availableTokens[_indexToUse] = lastValInArray;
                // Gas refund courtesy of @dievardump
                delete _availableTokens[lastIndex];
            }
        }

        return result;
    }

    // CLAIM FUNCTIONS
    struct ClaimData {
        address to;
        uint256 start;
        uint256 count;
    }

    /**
    * Claim all tokens for sender.
    */
    function claimAll() external {
        require(isClaimActive(), "claim is not active");
        address owner = _msgSender();
        IChainRunners genesisContract = IChainRunners(genesisContractAddress);
        uint256 balance = genesisContract.balanceOf(owner);
        ClaimData memory batch;
        unchecked {
            for (uint256 i; i < balance; i++) {
                uint256 tokenId = genesisContract.tokenOfOwnerByIndex(owner, i);
                if (!isClaimed(tokenId)) {
                    if (batch.start == 0) {
                        batch.to = owner;
                        batch.start = tokenId;
                        batch.count = 1;
                    } else if (((batch.start+batch.count) != tokenId) || (batch.count == MAX_BATCH_SIZE)) {
                        _claim(batch.to, batch.start, batch.count);
                        batch.start = tokenId;
                        batch.count = 1;
                    } else {
                        batch.count++;
                    }
                    if (i == balance - 1) {
                        // Claim last batch
                       _claim(batch.to, batch.start, batch.count);
                    }
                    _setClaimed(tokenId);
                }
            }
        }
    }

    function claimsRemaining(address owner) public view returns (uint256) {
        IChainRunners genesisContract = IChainRunners(genesisContractAddress);
        uint256 balance = genesisContract.balanceOf(owner);
        unchecked {
            uint256 _claimsRemaining;
            for (uint256 i; i < balance; i++) {
                uint256 tokenId = genesisContract.tokenOfOwnerByIndex(owner, i);
                if (!isClaimed(tokenId)) {
                    _claimsRemaining++;
                }
            }
            return _claimsRemaining;
        }
    }

    function isClaimed(uint256 _tokenId) public view returns (bool) {
        uint256 claimedWordIndex = _tokenId / 256;
        uint256 claimedBitIndex = _tokenId % 256;
        uint256 claimedWord = claimedBitMap[claimedWordIndex];
        uint256 mask = (1 << claimedBitIndex);
        return claimedWord & mask == mask;
    }

    function _setClaimed(uint256 _tokenId) internal {
        uint256 claimedWordIndex = _tokenId / 256;
        uint256 claimedBitIndex = _tokenId % 256;
        claimedBitMap[claimedWordIndex] = claimedBitMap[claimedWordIndex] | (1 << claimedBitIndex);
    }

    function refundIfOver(uint256 _price) private {
        require(msg.value >= _price, "Need to send more ETH.");
        if (msg.value > _price) {
            payable(msg.sender).transfer(msg.value - _price);
        }
    }

    // RENDERING FUNCTIONS
    function getDna(uint256 _tokenId) public view returns (uint256) {
        IChainRunners genesisContract = IChainRunners(genesisContractAddress);
        uint256 dna_;
        if (_tokenId <= mintCollectionSize) {
            dna_ = genesisContract.getDna(_tokenId);
        } else {
            uint256 contentId = tokenIdToContentIdMapping[_tokenId];
            dna_ = uint256(keccak256(abi.encodePacked(
                revealSeed + (contentId % mintCollectionSize)
            )));
        }
        return dna_;
    }

    function tokenURI(uint256 _tokenId) public view virtual override returns (string memory) {
        require(_exists(_tokenId), "ERC721Metadata: URI query for nonexistent token");
        if (xrRendererContractAddress == address(0) || revealSeed == 0) {
            return '';
        }
        IChainRunnersRenderer renderer = IChainRunnersRenderer(xrRendererContractAddress);
        ChainRunnersTypes.ChainRunner memory runner;
        runner.dna = getDna(_tokenId);
        return renderer.tokenURI(_tokenId, runner);
    }

    // MISC FUNCTIONS
    function withdraw() public onlyOwner {
        (bool succ,) = payable(msg.sender).call{value : address(this).balance}("");
        require(succ, "transfer failed");
    }

    function ownershipStartTimestamp(uint256 _tokenId) public view returns (uint256) {
        (TokenOwnership memory ownership, ) = _ownershipOf(_tokenId);
        return ownership.startTimestamp;
    }

    function burn(uint256 tokenId) external {
        require(isBurningActive(), "burning not active");
        _burn(tokenId, true);
    }

    function isBurningActive() public view returns (bool) {
        return
        burningStartTimestamp != 0 &&
        block.timestamp >= burningStartTimestamp;
    }

    function setBurningStartTimestamp(uint256 _timestamp) public {
        burningStartTimestamp = _timestamp;
    }
}

// File: contracts/ChainRunnersItems.sol



import "@openzeppelin/contracts/token/ERC1155/extensions/ERC1155Supply.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "./ItemManagerPermissions.sol";

interface ChainRunnersItemRenderer {
    function uri(uint256 id) external view returns (string memory);
}

contract ChainRunnersItems is ERC1155Supply, ItemManagerPermissions {

    address private _rendererAddress;
    mapping(uint256 => uint256) private _mintEndTimes;
    mapping(uint256 => uint256) private _maxSupplies;
    mapping(uint256 => uint256) private _totalSupplies;

    error MintingEnded();
    error MaxTokenSupplyExceeded();
    error ChangeMaxTokenSupply();
    error ChangeMintingEndDate();
    error CallerNotOwnerNorApproved();

    constructor() ERC1155('') {}

    // MODIFIERS
    modifier whenMintActive(uint256 id) {
        if (!isMintActive(id)) revert MintingEnded();
        _;
    }

    modifier whenMintBatchActive(uint256[] memory ids) {
        for (uint256 i; i < ids.length; i++) {
            if (!isMintActive(ids[i])) revert MintingEnded();
        }
        _;
    }

    // ADMIN FUNCTIONS
    function setMaxSupply(uint256 id, uint256 supply) public onlyOwner {
        if (_maxSupplies[id] > 0) revert ChangeMaxTokenSupply();
        _maxSupplies[id] = supply;
    }

    function setMintEndTime(uint256 id, uint256 endTime) public onlyOwner {
        if (_mintEndTimes[id] > 0) revert ChangeMintingEndDate();
        _mintEndTimes[id] = endTime;
    }

    function setRendererAddress(address rendererAddress) public onlyOwner {
        _rendererAddress = rendererAddress;
    }

    // READ FUNCTIONS
    function maxSupply(uint256 id) public view returns (uint256) {
        return _maxSupplies[id];
    }

    function mintEndTime(uint256 id) public view returns (uint256) {
        return _mintEndTimes[id];
    }

    function isMintActive(uint256 id) public view returns (bool) {
        return _mintEndTimes[id] == 0 || (block.timestamp <= _mintEndTimes[id]);
    }

    function rendererAddress() public view returns (address) {
        return _rendererAddress;
    }

    // MINTING FUNCTIONS
    function mint(address[] calldata addresses, uint256 id, uint256 amount) external onlyItemManager whenMintActive(id) {
        for (uint256 i; i < addresses.length; i++) {
            if (_maxSupplies[id] > 0 && (amount + _totalSupplies[id]) > _maxSupplies[id]) revert MaxTokenSupplyExceeded();
            // Update supply before mint for reentrancy protection
            _totalSupplies[id] += amount;
            _mint(addresses[i], id, amount, '');
        }
    }

    function mintBatch(address[] calldata addresses, uint256[] calldata ids, uint256[] calldata amounts) external onlyItemManager whenMintBatchActive(ids) {
        require(ids.length == amounts.length);
        for (uint256 i; i < ids.length; i++) {
            if (_maxSupplies[ids[i]] > 0 && (_totalSupplies[ids[i]] + (amounts[i] * addresses.length)) > _maxSupplies[ids[i]]) revert MaxTokenSupplyExceeded();
            // Update supply before mint for reentrancy protection
            _totalSupplies[ids[i]] += (amounts[i] * addresses.length);
        }
        for (uint256 j; j < addresses.length; j++) {
            _mintBatch(addresses[j], ids, amounts, '');
        }
    }

    // BURNING FUNCTIONS
    function burn(address[] calldata addresses, uint256 id, uint256 amount) external onlyItemManager {
        for (uint256 i; i < addresses.length; i++) {
            if (addresses[i] != _msgSender() && !isApprovedForAll(addresses[i], _msgSender())) revert CallerNotOwnerNorApproved();
            _burn(addresses[i], id, amount);
        }
    }

    function burnBatch(address[] calldata addresses, uint256[] calldata ids, uint256[] calldata amounts) external onlyItemManager {
        for (uint256 i; i < addresses.length; i++) {
            if (addresses[i] != _msgSender() && !isApprovedForAll(addresses[i], _msgSender())) revert CallerNotOwnerNorApproved();
            _burnBatch(addresses[i], ids, amounts);
        }
    }

    // RENDERING FUNCTIONS
    function uri(uint256 id) public view override returns (string memory) {
        ChainRunnersItemRenderer renderer = ChainRunnersItemRenderer(_rendererAddress);
        return renderer.uri(id);
    }
}
// File: contracts/ChainRunners.sol



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

import "@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/utils/Counters.sol";
import "./core/ChainRunnersTypes.sol";
import "./interfaces/IChainRunnersRenderer.sol";

/*
               ::::                                                                                                                                                  :::#%=
               @*==+-                                                                                                                                               ++==*=.
               #+=#=++..                                                                                                                                        ..=*=*+-#:
                :=+++++++=====================================:    .===============================================. .=========================================++++++++=
                 .%-+%##+=--==================================+=..=+-=============================================-+*+======================================---+##+=#-.
                   -+++@@%++++@@@%+++++++++++++++++++++++++++%#++++++%#+++#@@@#+++++++++@@%++++++++++++++++++++@#+.=+*@*+*@@@@*+++++++++++++++++++++++%@@@#+++#@@+++=
                    -*-#%@@%%%=*%@%*++=++=+==+=++=++=+=++=++==#@%#%#+++=+=*@%*+=+==+=+++%*++==+=++=+==+=++=+=++@%%#%#++++*@%#++=++=++=++=+=++=++=+=+*%%*==*%@@@*:%=
                     :@:+@@@@@@*+++%@@*+===========+*=========#@@========+#%==========*@========##*#*+=======*@##*======#@#+=======*#*============+#%++#@@%#@@#++=.
                      .*+=%@%*%@%##++@@%#=-==-=--==*%=========*%==--=--=-====--=--=-=##=--=-=--%%%%%+=-=--=-=*%=--=--=-=#%=--=----=#%=--=-=--=-+%#+==#%@@*#%@=++.
                        +%.#@@###%@@@@@%*---------#@%########@%*---------------------##---------------------##---------%%*--------@@#---------+#@=#@@#+==@@%*++-
                        .:*+*%@#+=*%@@@*=-------=#%#=-------=%*---------=*#*--------#+=--------===--------=#%*-------=#%*-------==@%#--------=%@@%#*+=-+#%*+*:.
       ====================%*.@@%#==+##%@*=----------------+@#+---------@@*-------=*@+---------@@*--------=@+--------+@=--------*@@+-------+#@@%#==---+#@.*%====================
     :*=--==================-:=#@@%*===+*@%+=============%%%@=========*%@*========+@+=--=====+%@+==========@+========+@========*%@@+======%%%**+=---=%@#=:-====================-#-
       +++**%@@@#*****************@#*=---=##%@@@@@@@@@@@@@#**@@@@****************%@@*+++@#***********#@************************************+=------=*@#*********************@#+=+:
        .-##=*@@%*----------------+%@%=---===+%@@@@@@@*+++---%#++----------------=*@@*+++=-----------=+#=------------------------------------------+%+--------------------+#@-=@
         :%:#%#####+=-=-*@@+--=-==-=*@=--=-==-=*@@#*=-==-=-+@===-==-=-=++==-=-==--=@%===-==----+-==-==--+*+-==-==---=*@@@@@@%#===-=-=+%@%-==-=-==-#@%=-==-==--+#@@@@@@@@@@@@*+++
        =*=#@#=----==-=-=++=--=-==-=*@=--=-==-=*@@+-=-==-==+@===-=--=-*@@*=-=-==--+@=--=-==--+#@-==-==---+%-==-==---=+++#@@@#--==-=-=++++-=--=-===#%+=-==-==---=++++++++@@@%.#*
        +#:@%*===================++%#=========%@%=========#%=========+#@%+=======#%==========*@#=========*%=========+*+%@@@+========+*==========+@@%+**+================*%#*=+=
       *++#@*+=++++++*#%*+++++=+++*%%++++=++++%%*=+++++++##*=++++=++=%@@++++=++=+#%++++=++++#%@=+++++++=*#*+++++++=#%@@@@@*++=++++=#%@*+++=++=+++@#*****=+++++++=+++++*%@@+:=+=
    :=*=#%#@@@@#%@@@%#@@#++++++++++%%*+++++++++++++++++**@*+++++++++*%#++++++++=*##++++++++*%@%+++++++++##+++++++++#%%%%%%++++**#@@@@@**+++++++++++++++++=*%@@@%#@@@@#%@@@%#@++*:.
    #*:@#=-+%#+:=*@*=-+@%#++++++++#%@@#*++++++++++++++#%@#*++++++++*@@#+++++++++@#++++++++*@@#+++++++++##*+++++++++++++++++###@@@@++*@@#+++++++++++++++++++*@@#=:+#%+--+@*=-+%*.@=
    ++=#%#+%@@%=#%@%#+%%#++++++*#@@@%###**************@@@++++++++**#@##*********#*********#@@#++++++***@#******%@%#*++**#@@@%##+==+++=*#**********%%*++++++++#%#=%@@%+*%@%*+%#*=*-
     .-*+===========*@@+++++*%%%@@@++***************+.%%*++++#%%%@@%=:=******************--@@#+++*%%@#==+***--*@%*++*%@@*===+**=--   -************++@%%#++++++#@@@*==========*+-
        =*******##.#%#++++*%@@@%+==+=             *#-%@%**%%###*====**-               -@:*@@##@###*==+**-.-#=+@@#*@##*==+***=                     =+=##%@*+++++*%@@#.#%******:
               ++++%#+++*#@@@@+++==.              **-@@@%+++++++===-                 -+++#@@+++++++==:  :+++%@@+++++++==:                          .=++++@%##++++@@%++++
             :%:*%%****%@@%+==*-                .%==*====**+...                      #*.#+==***....    #+=#%+==****:.                                ..-*=*%@%#++*#%@=+%.
            -+++#%+#%@@@#++===                  .@*++===-                            #%++===           %#+++===                                          =+++%@%##**@@*.@:
          .%-=%@##@@%*==++                                                                                                                                 .*==+#@@%*%@%=*=.
         .+++#@@@@@*++==.                                                                                                                                    -==++#@@@@@@=+%
       .=*=%@@%%%#=*=.                                                                                                                                          .*+=%@@@@%+-#.
       @=-@@@%:++++.                                                                                                                                              -+++**@@#+*=:
    .-+=*#%%++*::.                                                                                                                                                  :+**=#%@#==#
    #*:@*+++=:                                                                                                                                                          =+++@*++=:
  :*-=*=++..                                                                                                                                                             .=*=#*.%=
 +#.=+++:                                                                                                                                                                   ++++:+#
*+=#-::                                                                                                                                                                      .::*+=*

*/

contract ChainRunners is ERC721Enumerable, Ownable, ReentrancyGuard {
    mapping(uint256 => ChainRunnersTypes.ChainRunner) runners;

    address public renderingContractAddress;

    event GenerateRunner(uint256 indexed tokenId, uint256 dna);
    using Counters for Counters.Counter;
    Counters.Counter private _tokenIds;
    Counters.Counter private _reservedTokenIds;

    uint256 private constant MAX_RUNNERS = 10000;
    uint256 private constant FOUNDERS_RESERVE_AMOUNT = 85;
    uint256 private constant MAX_PUBLIC_RUNNERS = MAX_RUNNERS - FOUNDERS_RESERVE_AMOUNT;
    uint256 private constant MINT_PRICE = 0.05 ether;
    uint256 private constant MAX_PER_ADDRESS = 10;

    uint256 private constant MAX_PER_EARLY_ACCESS_ADDRESS = 5;

    uint256 private runnerZeroHash;
    uint256 private runnerZeroDNA;

    uint256 public earlyAccessStartTimestamp;
    uint256 public publicSaleStartTimestamp;

    mapping(address => bool) public isOnEarlyAccessList;
    mapping(address => uint256) public earlyAccessMintedCounts;
    mapping(address => uint256) private founderMintCountsRemaining;

    constructor() ERC721("Chain Runners", "RUN") {}

    modifier whenPublicSaleActive() {
        require(isPublicSaleOpen(), "Public sale not open");
        _;
    }

    modifier whenEarlyAccessActive() {
        require(isEarlyAccessOpen(), "Early access not open");
        _;
    }

    function setRenderingContractAddress(address _renderingContractAddress) public onlyOwner {
        renderingContractAddress = _renderingContractAddress;
    }

    function mintPublicSale(uint256 _count) external payable nonReentrant whenPublicSaleActive returns (uint256, uint256) {
        require(_count > 0 && _count <= MAX_PER_ADDRESS, "Invalid Runner count");
        require(_tokenIds.current() + _count <= MAX_PUBLIC_RUNNERS, "All Runners have been minted");
        require(_count * MINT_PRICE == msg.value, "Incorrect amount of ether sent");

        uint256 firstMintedId = _tokenIds.current() + 1;

        for (uint256 i = 0; i < _count; i++) {
            _tokenIds.increment();
            mint(_tokenIds.current());
        }

        return (firstMintedId, _count);
    }

    function mintEarlyAccess(uint256 _count) external payable nonReentrant whenEarlyAccessActive returns (uint256, uint256) {
        require(_count != 0, "Invalid Runner count");
        require(isOnEarlyAccessList[msg.sender], "Address not on Early Access list");
        require(_tokenIds.current() + _count <= MAX_PUBLIC_RUNNERS, "All Runners have been minted");
        require(_count * MINT_PRICE == msg.value, "Incorrect amount of ether sent");

        uint256 userMintedAmount = earlyAccessMintedCounts[msg.sender] + _count;
        require(userMintedAmount <= MAX_PER_EARLY_ACCESS_ADDRESS, "Max Early Access count per address exceeded");

        uint256 firstMintedId = _tokenIds.current() + 1;
        for (uint256 i = 0; i < _count; i++) {
            _tokenIds.increment();
            mint(_tokenIds.current());
        }
        earlyAccessMintedCounts[msg.sender] = userMintedAmount;
        return (firstMintedId, _count);
    }

    function allocateFounderMint(address _addr, uint256 _count) public onlyOwner nonReentrant {
        founderMintCountsRemaining[_addr] = _count;
    }

    function founderMint(uint256 _count) public nonReentrant returns (uint256, uint256) {
        require(_count > 0 && _count <= MAX_PER_ADDRESS, "Invalid Runner count");
        require(_reservedTokenIds.current() + _count <= FOUNDERS_RESERVE_AMOUNT, "All reserved Runners have been minted");
        require(founderMintCountsRemaining[msg.sender] >= _count, "You cannot mint this many reserved Runners");

        uint256 firstMintedId = MAX_PUBLIC_RUNNERS + _tokenIds.current() + 1;
        for (uint256 i = 0; i < _count; i++) {
            _reservedTokenIds.increment();
            mint(MAX_PUBLIC_RUNNERS + _reservedTokenIds.current());
        }
        founderMintCountsRemaining[msg.sender] -= _count;
        return (firstMintedId, _count);
    }

    function mint(uint256 tokenId) internal {
        ChainRunnersTypes.ChainRunner memory runner;
        runner.dna = uint256(keccak256(abi.encodePacked(
                tokenId,
                msg.sender,
                block.difficulty,
                block.timestamp
            )));

        _safeMint(msg.sender, tokenId);
        runners[tokenId] = runner;
    }

    function getRemainingEarlyAccessMints(address _addr) public view returns (uint256) {
        if (!isOnEarlyAccessList[_addr]) {
            return 0;
        }
        return MAX_PER_EARLY_ACCESS_ADDRESS - earlyAccessMintedCounts[_addr];
    }

    function getRemainingFounderMints(address _addr) public view returns (uint256) {
        return founderMintCountsRemaining[_addr];
    }

    function isPublicSaleOpen() public view returns (bool) {
        return block.timestamp >= publicSaleStartTimestamp && publicSaleStartTimestamp != 0;
    }

    function isEarlyAccessOpen() public view returns (bool) {
        return !isPublicSaleOpen() && block.timestamp >= earlyAccessStartTimestamp && earlyAccessStartTimestamp != 0;
    }

    function addToEarlyAccessList(address[] memory toEarlyAccessList) external onlyOwner {
        for (uint256 i = 0; i < toEarlyAccessList.length; i++) {
            isOnEarlyAccessList[toEarlyAccessList[i]] = true;
        }
    }

    function removeFromEarlyAccessList(address[] memory toRemove) external onlyOwner {
        for (uint256 i = 0; i < toRemove.length; i++) {
            isOnEarlyAccessList[toRemove[i]] = false;
        }
    }

    function setPublicSaleTimestamp(uint256 timestamp) external onlyOwner {
        publicSaleStartTimestamp = timestamp;
    }

    function setEarlyAccessTimestamp(uint256 timestamp) external onlyOwner {
        earlyAccessStartTimestamp = timestamp;
    }

    function checkHash(string memory seed) public view returns (uint256) {
        return uint256(keccak256(abi.encodePacked(seed)));
    }

    function configureRunnerZero(uint256 _runnerZeroHash, uint256 _runnerZeroDNA) external onlyOwner {
        require(runnerZeroHash == 0, "Runner Zero has already been configured");
        runnerZeroHash = _runnerZeroHash;
        runnerZeroDNA = _runnerZeroDNA;
    }

    function mintRunnerZero(string memory seed) external {
        require(runnerZeroHash != 0, "Runner Zero has not been configured");
        require(!_exists(0), "Runner Zero has already been minted");
        require(checkHash(seed) == runnerZeroHash, "Incorrect seed");

        ChainRunnersTypes.ChainRunner memory runner;
        runner.dna = runnerZeroDNA;

        _safeMint(msg.sender, 0);
        runners[0] = runner;
    }

    function tokenURI(uint256 _tokenId) public view virtual override returns (string memory) {
        require(_exists(_tokenId), "ERC721Metadata: URI query for nonexistent token");

        if (renderingContractAddress == address(0)) {
            return '';
        }

        IChainRunnersRenderer renderer = IChainRunnersRenderer(renderingContractAddress);
        return renderer.tokenURI(_tokenId, runners[_tokenId]);
    }

    function tokenURIForSeed(uint256 _tokenId, uint256 seed) public view virtual returns (string memory) {
        require(_exists(_tokenId), "ERC721Metadata: URI query for nonexistent token");

        if (renderingContractAddress == address(0)) {
            return '';
        }

        ChainRunnersTypes.ChainRunner memory runner;
        runner.dna = seed;

        IChainRunnersRenderer renderer = IChainRunnersRenderer(renderingContractAddress);
        return renderer.tokenURI(_tokenId, runner);
    }

    function getDna(uint256 _tokenId) public view returns (uint256) {
        return runners[_tokenId].dna;
    }

    receive() external payable {}

    function withdraw() public onlyOwner {
        (bool success,) = msg.sender.call{value : address(this).balance}('');
        require(success, "Withdrawal failed");
    }
}

// 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/interfaces/IChainRunnersRenderer.sol



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

import "../core/ChainRunnersTypes.sol";

interface IChainRunnersRenderer {
    function tokenURI(uint256 tokenId, ChainRunnersTypes.ChainRunner memory runnerData) external view returns (string memory);
}

// File: contracts/core/ERC721AClaimable.sol



// SPDX-License-Identifier: MIT
// Creator: Chain Runners, based on ERC721A by Chiru Labs

pragma solidity ^0.8.4;

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/Address.sol';
import '@openzeppelin/contracts/utils/Context.sol';
import '@openzeppelin/contracts/utils/Strings.sol';
import '@openzeppelin/contracts/utils/introspection/ERC165.sol';

error ApprovalCallerNotOwnerNorApproved();
error ApprovalQueryForNonexistentToken();
error ApproveToCaller();
error ApprovalToCurrentOwner();
error BalanceQueryForZeroAddress();
error MintToZeroAddress();
error MintZeroQuantity();
error OwnerQueryForNonexistentToken();
error TransferCallerNotOwnerNorApproved();
error TransferFromIncorrectOwner();
error TransferToNonERC721ReceiverImplementer();
error TransferToZeroAddress();
error URIQueryForNonexistentToken();

/**
 * @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
 * the Metadata extension. Built to optimize for lower gas during batch mints.
 *
 * This is a modification to the ERC721A contract that supports a non-sequential token claiming range from
 * _startClaimTokenId() to _startMintTokenId(), and a sequential minting range starting at _startMintTokenId().
 *
 * Assumes minted serials are sequentially minted starting at _startMintTokenId() (defaults to 10001, e.g. 10000, 10001, 10002, 10003..).
 *
 * Claimed tokens can be minted in any order between _startClaimTokenId() and _startMintTokenId() (defaults to 1, e.g. 1 to 10000)
 *
 * Assumes that an owner cannot have more than 2**64 - 1 (max value of uint64) of supply.
 *
 * Assumes that the maximum token id cannot exceed 2**256 - 1 (max value of uint256).
 */
contract ERC721AClaimable is Context, ERC165, IERC721, IERC721Metadata {
    using Address for address;
    using Strings for uint256;

    // Compiler will pack this into a single 256bit word.
    struct TokenOwnership {
        // The address of the owner.
        address addr;
        // Keeps track of the start time of ownership with minimal overhead for tokenomics.
        uint64 startTimestamp;
        // Whether the token has been burned.
        bool burned;
        // Keeps track of how many tokens (above) this ownership record covers.  Only set/useful for claims
        uint256 quantity;
    }

    // Compiler will pack this into a single 256bit word.
    struct AddressData {
        // Realistically, 2**64-1 is more than enough.
        uint64 balance;
        // Keeps track of mint count with minimal overhead for tokenomics.
        uint64 numberMinted;
        // Keeps track of burn count with minimal overhead for tokenomics.
        uint64 numberBurned;
        // For miscellaneous variable(s) pertaining to the address
        // (e.g. number of whitelist mint slots used).
        // If there are multiple variables, please pack them into a uint64.
        uint64 aux;
    }

    // The tokenId of the next token to be minted.
    uint256 internal _currentMintIndex;

    // The number of claimed tokens.
    uint256 internal _numClaimed;

    // Max batch size per mint
    uint256 internal _maxBatchSize;

    // The number of tokens burned.
    uint256 internal _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 _ownershipOf implementation for details.
    mapping(uint256 => TokenOwnership) internal _ownerships;

    // Mapping owner address to address data
    mapping(address => AddressData) private _addressData;

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

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

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

        _currentMintIndex = _startMintTokenId();

        _maxBatchSize = 5;
    }

    /**
     * To change the starting mintTokenId, please override this function.
     */
    function _startMintTokenId() internal view virtual returns (uint256) {
        return 10001;
    }

    /**
     * To change the starting claimTokenId, please override this function.
     */
    function _startClaimTokenId() internal view virtual returns (uint256) {
        return 1;
    }

    /**
     * @dev Burned tokens are calculated here, use _totalMinted() if you want to count just minted tokens.
     */
    function totalSupply() public view returns (uint256) {
        // Counter underflow is impossible as _burnCounter cannot be incremented
        // more than _currentIndex - _startMintTokenId() times
        unchecked {
            return (_currentMintIndex - _startMintTokenId())
            + _numClaimed
            - _burnCounter;
        }
    }

    /**
     * Returns the total amount of tokens minted in the contract.
     */
    function _totalMinted() public view returns (uint256) {
        unchecked {
            return _currentMintIndex - _startMintTokenId();
        }
    }

    /**
     * Returns the total amount of tokens claimed in the contract.
     */
    function totalClaimed() public view returns (uint256) {
        return _numClaimed;
    }

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
        return
        interfaceId == type(IERC721).interfaceId ||
        interfaceId == type(IERC721Metadata).interfaceId ||
        super.supportsInterface(interfaceId);
    }

    /**
     * @dev See {IERC721-balanceOf}.
     */
    function balanceOf(address owner) public view override returns (uint256) {
        if (owner == address(0)) revert BalanceQueryForZeroAddress();
        return uint256(_addressData[owner].balance);
    }

    /**
     * Returns the number of tokens minted by `owner`.
     */
    function _numberMinted(address owner) internal view returns (uint256) {
        return uint256(_addressData[owner].numberMinted);
    }

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

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

    /**
     * Sets the auxillary 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 {
        _addressData[owner].aux = aux;
    }

    /**
     * Gas spent here starts off proportional to the maximum mint batch size.
     * It gradually moves to O(1) as tokens get transferred around in the collection over time.
     */
    function _ownershipOf(uint256 tokenId) internal view returns (TokenOwnership memory, uint256 ownershipIndex) {
        uint256 curr = tokenId;

        TokenOwnership memory ownership = _ownerships[curr];
        if (!ownership.burned) {
            if (ownership.addr != address(0)) {
                return (ownership, tokenId);
            } else if (_startMintTokenId() <= curr && curr < _currentMintIndex) {
                // Invariant:
                // There will always be an ownership that has an address and is not burned
                // before an ownership that does not have an address and is not burned.
                // Hence, curr will not underflow.
                unchecked {
                    while (true) {
                        curr--;
                        ownership = _ownerships[curr];
                        if (ownership.addr != address(0)) {
                            return (ownership, curr);
                        }
                    }
                }
            } else if (_startClaimTokenId() <= curr && curr < _startMintTokenId()) {
                // Invariant:
                // These tokens are claimed in random order, but there will always be
                // an ownership that has an address and is not
                // burned within _maxBatchSize below tokenId.
                // Could underflow, so don't wrap in unchecked.
                uint256 lowestTokenToCheck = _startClaimTokenId();
                if (tokenId >= _maxBatchSize) {
                    lowestTokenToCheck = tokenId - _maxBatchSize + 1;
                }
                for (; curr >= lowestTokenToCheck && curr >= _startClaimTokenId(); curr--) {
                    ownership = _ownerships[curr];
                    if ((ownership.addr != address(0)) && ((curr + ownership.quantity - 1) >= tokenId)) {
                        return (ownership, curr);
                    }
                }
            }
        }
        revert OwnerQueryForNonexistentToken();
    }

    /**
     * @dev See {IERC721-ownerOf}.
     */
    function ownerOf(uint256 tokenId) public view override returns (address) {
        (TokenOwnership memory ownership, ) = _ownershipOf(tokenId);
        return ownership.addr;
    }

    /**
     * @dev See {IERC721Metadata-name}.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }

    /**
     * @dev See {IERC721Metadata-symbol}.
     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    /**
     * @dev See {IERC721Metadata-tokenURI}.
     */
    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, tokenId.toString())) : '';
    }

    /**
     * @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, can be overriden in child contracts.
     */
    function _baseURI() internal view virtual returns (string memory) {
        return '';
    }

    /**
     * @dev See {IERC721-approve}.
     */
    function approve(address to, uint256 tokenId) public override {
        address owner = ERC721AClaimable.ownerOf(tokenId);
        if (to == owner) revert ApprovalToCurrentOwner();

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

        _approve(to, tokenId, owner);
    }

    /**
     * @dev See {IERC721-getApproved}.
     */
    function getApproved(uint256 tokenId) public view override returns (address) {
        if (!_exists(tokenId)) revert ApprovalQueryForNonexistentToken();

        return _tokenApprovals[tokenId];
    }

    /**
     * @dev See {IERC721-setApprovalForAll}.
     */
    function setApprovalForAll(address operator, bool approved) public virtual override {
        if (operator == _msgSender()) revert ApproveToCaller();

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

    /**
     * @dev See {IERC721-isApprovedForAll}.
     */
    function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
        return _operatorApprovals[owner][operator];
    }

    /**
     * @dev See {IERC721-transferFrom}.
     */
    function transferFrom(
        address from,
        address to,
        uint256 tokenId
    ) public virtual override {
        _transfer(from, to, tokenId);
    }

    /**
     * @dev See {IERC721-safeTransferFrom}.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId
    ) public virtual override {
        safeTransferFrom(from, to, tokenId, '');
    }

    /**
     * @dev See {IERC721-safeTransferFrom}.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId,
        bytes memory _data
    ) public virtual override {
        _transfer(from, to, tokenId);
        if (to.isContract() && !_checkContractOnERC721Received(from, to, tokenId, _data)) {
            revert TransferToNonERC721ReceiverImplementer();
        }
    }

    /**
     * @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 (`_mint`) or claimed (`_claim`).
     */
    function _exists(uint256 tokenId) internal view returns (bool) {
        return ((_startMintTokenId() <= tokenId && tokenId < _currentMintIndex) ||
        _isClaimed(tokenId)) &&
        !_ownerships[tokenId].burned;
    }

    /**
    * @dev Returns whether `tokenId` has been claimed.
    */
    function _isClaimed(uint256 tokenId) internal view returns (bool) {
        uint256 curr = tokenId;
        if (_startClaimTokenId() <= curr && curr < _startMintTokenId()) {
            // Invariant:
            // These tokens are minted in random order, but if the token exists,
            // there will always be an ownership that has an address and is not
            // burned within _maxBatchSize below tokenId.
            uint256 lowestTokenToCheck = _startClaimTokenId();
            if (tokenId >= _maxBatchSize) {
                lowestTokenToCheck = tokenId - _maxBatchSize + 1;
            }
            for (; curr >= lowestTokenToCheck && curr >= _startClaimTokenId(); curr--) {
                TokenOwnership memory ownership = _ownerships[curr];
                if (ownership.addr != address(0)) {
                    return (curr + ownership.quantity - 1) >= tokenId;
                }
            }
        }
        return false;
    }

    /**
     * @dev Equivalent to `_safeMint(to, quantity, '')`.
     */
    function _safeMint(address to, uint256 quantity) internal {
        _safeMint(to, 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.
     *
     * Emits a {Transfer} event.
     */
    function _safeMint(
        address to,
        uint256 quantity,
        bytes memory _data
    ) internal {
        uint256 startTokenId = _currentMintIndex;
        if (to == address(0)) revert MintToZeroAddress();
        if (quantity == 0) revert MintZeroQuantity();

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

        // Overflows are incredibly unrealistic.
        // balance or numberMinted overflow if current value of either + quantity > 1.8e19 (2**64) - 1
        // updatedIndex overflows if _currentMintIndex + quantity > 1.2e77 (2**256) - 1
        unchecked {
            _addressData[to].balance += uint64(quantity);
            _addressData[to].numberMinted += uint64(quantity);

            _ownerships[startTokenId].addr = to;
            _ownerships[startTokenId].startTimestamp = uint64(block.timestamp);

            uint256 updatedIndex = startTokenId;
            uint256 end = updatedIndex + quantity;

            if (to.isContract()) {
                do {
                    emit Transfer(address(0), to, updatedIndex);
                    if (!_checkContractOnERC721Received(address(0), to, updatedIndex++, _data)) {
                        revert TransferToNonERC721ReceiverImplementer();
                    }
                } while (updatedIndex != end);
                // Reentrancy protection
                if (_currentMintIndex != startTokenId) revert();
            } else {
                do {
                    emit Transfer(address(0), to, updatedIndex++);
                } while (updatedIndex != end);
            }
            _currentMintIndex = updatedIndex;
        }
        _afterTokenTransfers(address(0), to, startTokenId, quantity);
    }

    /**
     * @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.
     */
    function _mint(address to, uint256 quantity) internal {
        uint256 startTokenId = _currentMintIndex;
        if (to == address(0)) revert MintToZeroAddress();
        if (quantity == 0) revert MintZeroQuantity();

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

        // Overflows are incredibly unrealistic.
        // balance or numberMinted overflow if current value of either + quantity > 1.8e19 (2**64) - 1
        // updatedIndex overflows if _currentMintIndex + quantity > 1.2e77 (2**256) - 1
        unchecked {
            _addressData[to].balance += uint64(quantity);
            _addressData[to].numberMinted += uint64(quantity);

            _ownerships[startTokenId].addr = to;
            _ownerships[startTokenId].startTimestamp = uint64(block.timestamp);

            uint256 updatedIndex = startTokenId;
            uint256 end = updatedIndex + quantity;

            do {
                emit Transfer(address(0), to, updatedIndex++);
            } while (updatedIndex != end);

            _currentMintIndex = updatedIndex;
        }
        _afterTokenTransfers(address(0), to, startTokenId, quantity);
    }

    /**
 * @dev Mints `quantity` tokens and transfers them to `to`.
     *
     * IMPORTANT NOTE: This operation is unsafe, since there is no check to ensure a taken has not been claimed.
     * Callers should check that a token hasn't been claimed before calling.
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - `quantity` must be greater than 0.
     *
     * Emits a {Transfer} event.
     */
    function _claim(address to, uint256 startTokenId, uint256 quantity) internal {
        if (to == address(0)) revert MintToZeroAddress();
        if (quantity == 0) revert MintZeroQuantity();

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

        // Overflows are incredibly unrealistic.
        // balance or numberMinted overflow if current value of either + quantity > 1.8e19 (2**64) - 1
        // updatedIndex overflows if _currentAirdropIndex + quantity > 1.2e77 (2**256) - 1
        unchecked {
            _addressData[to].balance += uint64(quantity);
            _addressData[to].numberMinted += uint64(quantity);

            _ownerships[startTokenId].addr = to;
            _ownerships[startTokenId].startTimestamp = uint64(block.timestamp);
            _ownerships[startTokenId].quantity = quantity;

            uint256 updatedIndex = startTokenId;
            uint256 end = updatedIndex + quantity;

            do {
                emit Transfer(address(0), to, updatedIndex++);
            } while (updatedIndex != end);

            _numClaimed += quantity;

            _afterTokenTransfers(address(0), to, startTokenId, quantity);
        }
    }

    /**
     * @dev Transfers `tokenId` from `from` to `to`.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     *
     * Emits a {Transfer} event.
     */
    function _transfer(
        address from,
        address to,
        uint256 tokenId
    ) private {
        (TokenOwnership memory prevOwnership, uint256 prevOwnershipIndex) = _ownershipOf(tokenId);

        if (prevOwnership.addr != from) revert TransferFromIncorrectOwner();

        bool isApprovedOrOwner = (_msgSender() == from ||
        isApprovedForAll(from, _msgSender()) ||
        getApproved(tokenId) == _msgSender());

        if (!isApprovedOrOwner) revert TransferCallerNotOwnerNorApproved();
        if (to == address(0)) revert TransferToZeroAddress();

        _beforeTokenTransfers(from, to, tokenId, 1);

        // Clear approvals from the previous owner
        _approve(address(0), tokenId, from);

        // 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.
        TokenOwnership storage currSlot = _ownerships[tokenId];
        unchecked {
            _addressData[from].balance -= 1;
            _addressData[to].balance += 1;

            currSlot.addr = to;
            currSlot.startTimestamp = uint64(block.timestamp);
        }

        // Consider removing this.  It's not likely needed, as
        // - ownership checks for currSlot now have an ownership record and will immediately return
        // - now that currSlot is set, we will only hit the _ownerships[prevOwnershipIndex] ownership record
        // for ownership checks between _ownerships[prevOwnershipIndex] and currSlot.  Any checks above currSlot will
        // be covered by nextSlot, which is set below.
        uint256 prevOwnershipQuantity = prevOwnership.quantity;
        if (_startClaimTokenId() <= tokenId && tokenId < _startMintTokenId()) {
            currSlot.quantity = 1;
            _ownerships[prevOwnershipIndex].quantity = tokenId - prevOwnershipIndex + 1;
        }

        // If the ownership slot of tokenId+1 is not explicitly set, that means the transfer initiator owns it.
        // Set the slot of tokenId+1 explicitly in storage to maintain correctness for ownerOf(tokenId+1) calls.
        uint256 nextTokenId = tokenId + 1;
        TokenOwnership storage nextSlot = _ownerships[nextTokenId];
        if (nextSlot.addr == address(0)) {
            // This will suffice for checking _exists(nextTokenId) on minted tokens,
            // as a burned slot cannot contain the zero address.
            if ((_startMintTokenId() <= tokenId && tokenId < _currentMintIndex)) {
                nextSlot.addr = from;
                nextSlot.startTimestamp = prevOwnership.startTimestamp;
            } else if ((prevOwnershipIndex + prevOwnershipQuantity - 1) > tokenId) {
                nextSlot.addr = from;
                nextSlot.startTimestamp = prevOwnership.startTimestamp;
                nextSlot.quantity = prevOwnershipIndex + prevOwnershipQuantity - 1 - tokenId;
            }
        }

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

    /**
     * @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 {
        (TokenOwnership memory prevOwnership, uint256 prevOwnershipIndex) = _ownershipOf(tokenId);

        address from = prevOwnership.addr;

        if (approvalCheck) {
            bool isApprovedOrOwner = (_msgSender() == from ||
            isApprovedForAll(from, _msgSender()) ||
            getApproved(tokenId) == _msgSender());

            if (!isApprovedOrOwner) revert TransferCallerNotOwnerNorApproved();
        }

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

        // Clear approvals from the previous owner
        _approve(address(0), tokenId, from);

        // 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.
        TokenOwnership storage currSlot = _ownerships[tokenId];
        unchecked {
            AddressData storage addressData = _addressData[from];
            addressData.balance -= 1;
            addressData.numberBurned += 1;

            // Keep track of who burned the token, and the timestamp of burning.
            currSlot.addr = from;
            currSlot.startTimestamp = uint64(block.timestamp);
            currSlot.burned = true;
        }

        // Consider removing this.  It's not likely needed, as
        // - ownership checks for currSlot now have an ownership record and will immediately return
        // - now that currSlot is set, we will only hit the _ownerships[prevOwnershipIndex] ownership record
        // for ownership checks between _ownerships[prevOwnershipIndex] and currSlot.  Any checks above currSlot will
        // be covered by nextSlot, which is set below.
        uint256 prevOwnershipQuantity = prevOwnership.quantity;
        if (_startClaimTokenId() <= tokenId && tokenId < _startMintTokenId()) {
            currSlot.quantity = 1;
            _ownerships[prevOwnershipIndex].quantity = tokenId - prevOwnershipIndex + 1;
        }

        // If the ownership slot of tokenId+1 is not explicitly set, that means the burn initiator owns it.
        // Set the slot of tokenId+1 explicitly in storage to maintain correctness for ownerOf(tokenId+1) calls.
        uint256 nextTokenId = tokenId + 1;
        TokenOwnership storage nextSlot = _ownerships[nextTokenId];
        if (nextSlot.addr == address(0)) {
            // This will suffice for checking _exists(nextTokenId),
            // as a burned slot cannot contain the zero address.
            if ((_startMintTokenId() <= tokenId && tokenId < _currentMintIndex)) {
                nextSlot.addr = from;
                nextSlot.startTimestamp = prevOwnership.startTimestamp;
            } else if ((prevOwnershipIndex + prevOwnershipQuantity - 1) > tokenId) {
                nextSlot.addr = from;
                nextSlot.startTimestamp = prevOwnership.startTimestamp;
                nextSlot.quantity = prevOwnershipIndex + prevOwnershipQuantity - 1 - tokenId;
            }
        }

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

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

    /**
     * @dev Approve `to` to operate on `tokenId`
     *
     * Emits a {Approval} event.
     */
    function _approve(
        address to,
        uint256 tokenId,
        address owner
    ) private {
        _tokenApprovals[tokenId] = to;
        emit Approval(owner, to, tokenId);
    }

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

    /**
     * @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 {}
}
// File: contracts/interfaces/IChainRunners.sol



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

import "@openzeppelin/contracts/token/ERC721/extensions/IERC721Enumerable.sol";
import "../core/ChainRunnersTypes.sol";

interface IChainRunners is IERC721Enumerable {
    function getDna(uint256 _tokenId) external view returns (uint256);
}

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



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

pragma solidity ^0.8.0;

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

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

    uint256 private _status;

    constructor() {
        _status = _NOT_ENTERED;
    }

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

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

        _;

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

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



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

pragma solidity ^0.8.0;

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

// File: contracts/core/ChainRunnersTypes.sol



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

interface ChainRunnersTypes {
    struct ChainRunner {
        uint256 dna;
    }
}

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



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

pragma solidity ^0.8.1;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.

        return account.code.length > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");

        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                /// @solidity memory-safe-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

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



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

pragma solidity ^0.8.0;

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

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

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



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

pragma solidity ^0.8.0;

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

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

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

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

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

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

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

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

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

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

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

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

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

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



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

pragma solidity ^0.8.0;

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

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

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

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

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

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

// File: @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/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/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/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/ItemManagerPermissions.sol



import "@openzeppelin/contracts/access/Ownable.sol";

contract ItemManagerPermissions is Ownable {
    mapping(address => bool) private _allowlistedAddresses;

    event ItemManagerAllowlistUpdated(address indexed itemManager, bool allowlisted);

    error NotAllowedToManageItem();

    // MODIFIERS
    modifier onlyItemManager() {
        if (!isAddressAllowlisted(_msgSender())) revert NotAllowedToManageItem();
        _;
    }

    // ADMIN FUNCTIONS
    function allowlistAddress(address addr) external onlyOwner {
        _allowlistedAddresses[addr] = true;
        emit ItemManagerAllowlistUpdated(addr, true);
    }

    function removeAllowlistedAddress(address addr) external onlyOwner {
        delete _allowlistedAddresses[addr];
        emit ItemManagerAllowlistUpdated(addr, false);
    }

    // READ FUNCTIONS
    function isAddressAllowlisted(address addr) public view returns (bool) {
        return _allowlistedAddresses[addr] == true;
    }
}
// File: @openzeppelin/contracts/token/ERC1155/extensions/ERC1155Supply.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC1155/extensions/ERC1155Supply.sol)

pragma solidity ^0.8.0;

import "../ERC1155.sol";

/**
 * @dev Extension of ERC1155 that adds tracking of total supply per id.
 *
 * Useful for scenarios where Fungible and Non-fungible tokens have to be
 * clearly identified. Note: While a totalSupply of 1 might mean the
 * corresponding is an NFT, there is no guarantees that no other token with the
 * same id are not going to be minted.
 */
abstract contract ERC1155Supply is ERC1155 {
    mapping(uint256 => uint256) private _totalSupply;

    /**
     * @dev Total amount of tokens in with a given id.
     */
    function totalSupply(uint256 id) public view virtual returns (uint256) {
        return _totalSupply[id];
    }

    /**
     * @dev Indicates whether any token exist with a given id, or not.
     */
    function exists(uint256 id) public view virtual returns (bool) {
        return ERC1155Supply.totalSupply(id) > 0;
    }

    /**
     * @dev See {ERC1155-_beforeTokenTransfer}.
     */
    function _beforeTokenTransfer(
        address operator,
        address from,
        address to,
        uint256[] memory ids,
        uint256[] memory amounts,
        bytes memory data
    ) internal virtual override {
        super._beforeTokenTransfer(operator, from, to, ids, amounts, data);

        if (from == address(0)) {
            for (uint256 i = 0; i < ids.length; ++i) {
                _totalSupply[ids[i]] += amounts[i];
            }
        }

        if (to == address(0)) {
            for (uint256 i = 0; i < ids.length; ++i) {
                uint256 id = ids[i];
                uint256 amount = amounts[i];
                uint256 supply = _totalSupply[id];
                require(supply >= amount, "ERC1155: burn amount exceeds totalSupply");
                unchecked {
                    _totalSupply[id] = supply - amount;
                }
            }
        }
    }
}

// File: @openzeppelin/contracts/token/ERC1155/ERC1155.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC1155/ERC1155.sol)

pragma solidity ^0.8.0;

import "./IERC1155.sol";
import "./IERC1155Receiver.sol";
import "./extensions/IERC1155MetadataURI.sol";
import "../../utils/Address.sol";
import "../../utils/Context.sol";
import "../../utils/introspection/ERC165.sol";

/**
 * @dev Implementation of the basic standard multi-token.
 * See https://eips.ethereum.org/EIPS/eip-1155
 * Originally based on code by Enjin: https://github.com/enjin/erc-1155
 *
 * _Available since v3.1._
 */
contract ERC1155 is Context, ERC165, IERC1155, IERC1155MetadataURI {
    using Address for address;

    // Mapping from token ID to account balances
    mapping(uint256 => mapping(address => uint256)) private _balances;

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

    // Used as the URI for all token types by relying on ID substitution, e.g. https://token-cdn-domain/{id}.json
    string private _uri;

    /**
     * @dev See {_setURI}.
     */
    constructor(string memory uri_) {
        _setURI(uri_);
    }

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
        return
            interfaceId == type(IERC1155).interfaceId ||
            interfaceId == type(IERC1155MetadataURI).interfaceId ||
            super.supportsInterface(interfaceId);
    }

    /**
     * @dev See {IERC1155MetadataURI-uri}.
     *
     * This implementation returns the same URI for *all* token types. It relies
     * on the token type ID substitution mechanism
     * https://eips.ethereum.org/EIPS/eip-1155#metadata[defined in the EIP].
     *
     * Clients calling this function must replace the `\{id\}` substring with the
     * actual token type ID.
     */
    function uri(uint256) public view virtual override returns (string memory) {
        return _uri;
    }

    /**
     * @dev See {IERC1155-balanceOf}.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     */
    function balanceOf(address account, uint256 id) public view virtual override returns (uint256) {
        require(account != address(0), "ERC1155: address zero is not a valid owner");
        return _balances[id][account];
    }

    /**
     * @dev See {IERC1155-balanceOfBatch}.
     *
     * Requirements:
     *
     * - `accounts` and `ids` must have the same length.
     */
    function balanceOfBatch(address[] memory accounts, uint256[] memory ids)
        public
        view
        virtual
        override
        returns (uint256[] memory)
    {
        require(accounts.length == ids.length, "ERC1155: accounts and ids length mismatch");

        uint256[] memory batchBalances = new uint256[](accounts.length);

        for (uint256 i = 0; i < accounts.length; ++i) {
            batchBalances[i] = balanceOf(accounts[i], ids[i]);
        }

        return batchBalances;
    }

    /**
     * @dev See {IERC1155-setApprovalForAll}.
     */
    function setApprovalForAll(address operator, bool approved) public virtual override {
        _setApprovalForAll(_msgSender(), operator, approved);
    }

    /**
     * @dev See {IERC1155-isApprovedForAll}.
     */
    function isApprovedForAll(address account, address operator) public view virtual override returns (bool) {
        return _operatorApprovals[account][operator];
    }

    /**
     * @dev See {IERC1155-safeTransferFrom}.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 id,
        uint256 amount,
        bytes memory data
    ) public virtual override {
        require(
            from == _msgSender() || isApprovedForAll(from, _msgSender()),
            "ERC1155: caller is not token owner nor approved"
        );
        _safeTransferFrom(from, to, id, amount, data);
    }

    /**
     * @dev See {IERC1155-safeBatchTransferFrom}.
     */
    function safeBatchTransferFrom(
        address from,
        address to,
        uint256[] memory ids,
        uint256[] memory amounts,
        bytes memory data
    ) public virtual override {
        require(
            from == _msgSender() || isApprovedForAll(from, _msgSender()),
            "ERC1155: caller is not token owner nor approved"
        );
        _safeBatchTransferFrom(from, to, ids, amounts, data);
    }

    /**
     * @dev Transfers `amount` tokens of token type `id` from `from` to `to`.
     *
     * Emits a {TransferSingle} event.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - `from` must have a balance of tokens of type `id` of at least `amount`.
     * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155Received} and return the
     * acceptance magic value.
     */
    function _safeTransferFrom(
        address from,
        address to,
        uint256 id,
        uint256 amount,
        bytes memory data
    ) internal virtual {
        require(to != address(0), "ERC1155: transfer to the zero address");

        address operator = _msgSender();
        uint256[] memory ids = _asSingletonArray(id);
        uint256[] memory amounts = _asSingletonArray(amount);

        _beforeTokenTransfer(operator, from, to, ids, amounts, data);

        uint256 fromBalance = _balances[id][from];
        require(fromBalance >= amount, "ERC1155: insufficient balance for transfer");
        unchecked {
            _balances[id][from] = fromBalance - amount;
        }
        _balances[id][to] += amount;

        emit TransferSingle(operator, from, to, id, amount);

        _afterTokenTransfer(operator, from, to, ids, amounts, data);

        _doSafeTransferAcceptanceCheck(operator, from, to, id, amount, data);
    }

    /**
     * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {_safeTransferFrom}.
     *
     * Emits a {TransferBatch} event.
     *
     * Requirements:
     *
     * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155BatchReceived} and return the
     * acceptance magic value.
     */
    function _safeBatchTransferFrom(
        address from,
        address to,
        uint256[] memory ids,
        uint256[] memory amounts,
        bytes memory data
    ) internal virtual {
        require(ids.length == amounts.length, "ERC1155: ids and amounts length mismatch");
        require(to != address(0), "ERC1155: transfer to the zero address");

        address operator = _msgSender();

        _beforeTokenTransfer(operator, from, to, ids, amounts, data);

        for (uint256 i = 0; i < ids.length; ++i) {
            uint256 id = ids[i];
            uint256 amount = amounts[i];

            uint256 fromBalance = _balances[id][from];
            require(fromBalance >= amount, "ERC1155: insufficient balance for transfer");
            unchecked {
                _balances[id][from] = fromBalance - amount;
            }
            _balances[id][to] += amount;
        }

        emit TransferBatch(operator, from, to, ids, amounts);

        _afterTokenTransfer(operator, from, to, ids, amounts, data);

        _doSafeBatchTransferAcceptanceCheck(operator, from, to, ids, amounts, data);
    }

    /**
     * @dev Sets a new URI for all token types, by relying on the token type ID
     * substitution mechanism
     * https://eips.ethereum.org/EIPS/eip-1155#metadata[defined in the EIP].
     *
     * By this mechanism, any occurrence of the `\{id\}` substring in either the
     * URI or any of the amounts in the JSON file at said URI will be replaced by
     * clients with the token type ID.
     *
     * For example, the `https://token-cdn-domain/\{id\}.json` URI would be
     * interpreted by clients as
     * `https://token-cdn-domain/000000000000000000000000000000000000000000000000000000000004cce0.json`
     * for token type ID 0x4cce0.
     *
     * See {uri}.
     *
     * Because these URIs cannot be meaningfully represented by the {URI} event,
     * this function emits no events.
     */
    function _setURI(string memory newuri) internal virtual {
        _uri = newuri;
    }

    /**
     * @dev Creates `amount` tokens of token type `id`, and assigns them to `to`.
     *
     * Emits a {TransferSingle} event.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155Received} and return the
     * acceptance magic value.
     */
    function _mint(
        address to,
        uint256 id,
        uint256 amount,
        bytes memory data
    ) internal virtual {
        require(to != address(0), "ERC1155: mint to the zero address");

        address operator = _msgSender();
        uint256[] memory ids = _asSingletonArray(id);
        uint256[] memory amounts = _asSingletonArray(amount);

        _beforeTokenTransfer(operator, address(0), to, ids, amounts, data);

        _balances[id][to] += amount;
        emit TransferSingle(operator, address(0), to, id, amount);

        _afterTokenTransfer(operator, address(0), to, ids, amounts, data);

        _doSafeTransferAcceptanceCheck(operator, address(0), to, id, amount, data);
    }

    /**
     * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {_mint}.
     *
     * Emits a {TransferBatch} event.
     *
     * Requirements:
     *
     * - `ids` and `amounts` must have the same length.
     * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155BatchReceived} and return the
     * acceptance magic value.
     */
    function _mintBatch(
        address to,
        uint256[] memory ids,
        uint256[] memory amounts,
        bytes memory data
    ) internal virtual {
        require(to != address(0), "ERC1155: mint to the zero address");
        require(ids.length == amounts.length, "ERC1155: ids and amounts length mismatch");

        address operator = _msgSender();

        _beforeTokenTransfer(operator, address(0), to, ids, amounts, data);

        for (uint256 i = 0; i < ids.length; i++) {
            _balances[ids[i]][to] += amounts[i];
        }

        emit TransferBatch(operator, address(0), to, ids, amounts);

        _afterTokenTransfer(operator, address(0), to, ids, amounts, data);

        _doSafeBatchTransferAcceptanceCheck(operator, address(0), to, ids, amounts, data);
    }

    /**
     * @dev Destroys `amount` tokens of token type `id` from `from`
     *
     * Emits a {TransferSingle} event.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `from` must have at least `amount` tokens of token type `id`.
     */
    function _burn(
        address from,
        uint256 id,
        uint256 amount
    ) internal virtual {
        require(from != address(0), "ERC1155: burn from the zero address");

        address operator = _msgSender();
        uint256[] memory ids = _asSingletonArray(id);
        uint256[] memory amounts = _asSingletonArray(amount);

        _beforeTokenTransfer(operator, from, address(0), ids, amounts, "");

        uint256 fromBalance = _balances[id][from];
        require(fromBalance >= amount, "ERC1155: burn amount exceeds balance");
        unchecked {
            _balances[id][from] = fromBalance - amount;
        }

        emit TransferSingle(operator, from, address(0), id, amount);

        _afterTokenTransfer(operator, from, address(0), ids, amounts, "");
    }

    /**
     * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {_burn}.
     *
     * Emits a {TransferBatch} event.
     *
     * Requirements:
     *
     * - `ids` and `amounts` must have the same length.
     */
    function _burnBatch(
        address from,
        uint256[] memory ids,
        uint256[] memory amounts
    ) internal virtual {
        require(from != address(0), "ERC1155: burn from the zero address");
        require(ids.length == amounts.length, "ERC1155: ids and amounts length mismatch");

        address operator = _msgSender();

        _beforeTokenTransfer(operator, from, address(0), ids, amounts, "");

        for (uint256 i = 0; i < ids.length; i++) {
            uint256 id = ids[i];
            uint256 amount = amounts[i];

            uint256 fromBalance = _balances[id][from];
            require(fromBalance >= amount, "ERC1155: burn amount exceeds balance");
            unchecked {
                _balances[id][from] = fromBalance - amount;
            }
        }

        emit TransferBatch(operator, from, address(0), ids, amounts);

        _afterTokenTransfer(operator, from, address(0), ids, amounts, "");
    }

    /**
     * @dev Approve `operator` to operate on all of `owner` tokens
     *
     * Emits an {ApprovalForAll} event.
     */
    function _setApprovalForAll(
        address owner,
        address operator,
        bool approved
    ) internal virtual {
        require(owner != operator, "ERC1155: setting approval status for self");
        _operatorApprovals[owner][operator] = approved;
        emit ApprovalForAll(owner, operator, approved);
    }

    /**
     * @dev Hook that is called before any token transfer. This includes minting
     * and burning, as well as batched variants.
     *
     * The same hook is called on both single and batched variants. For single
     * transfers, the length of the `ids` and `amounts` arrays will be 1.
     *
     * Calling conditions (for each `id` and `amount` pair):
     *
     * - When `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * of token type `id` will be  transferred to `to`.
     * - When `from` is zero, `amount` tokens of token type `id` will be minted
     * for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens of token type `id`
     * will be burned.
     * - `from` and `to` are never both zero.
     * - `ids` and `amounts` have the same, non-zero length.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(
        address operator,
        address from,
        address to,
        uint256[] memory ids,
        uint256[] memory amounts,
        bytes memory data
    ) internal virtual {}

    /**
     * @dev Hook that is called after any token transfer. This includes minting
     * and burning, as well as batched variants.
     *
     * The same hook is called on both single and batched variants. For single
     * transfers, the length of the `id` and `amount` arrays will be 1.
     *
     * Calling conditions (for each `id` and `amount` pair):
     *
     * - When `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * of token type `id` will be  transferred to `to`.
     * - When `from` is zero, `amount` tokens of token type `id` will be minted
     * for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens of token type `id`
     * will be burned.
     * - `from` and `to` are never both zero.
     * - `ids` and `amounts` have the same, non-zero length.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _afterTokenTransfer(
        address operator,
        address from,
        address to,
        uint256[] memory ids,
        uint256[] memory amounts,
        bytes memory data
    ) internal virtual {}

    function _doSafeTransferAcceptanceCheck(
        address operator,
        address from,
        address to,
        uint256 id,
        uint256 amount,
        bytes memory data
    ) private {
        if (to.isContract()) {
            try IERC1155Receiver(to).onERC1155Received(operator, from, id, amount, data) returns (bytes4 response) {
                if (response != IERC1155Receiver.onERC1155Received.selector) {
                    revert("ERC1155: ERC1155Receiver rejected tokens");
                }
            } catch Error(string memory reason) {
                revert(reason);
            } catch {
                revert("ERC1155: transfer to non ERC1155Receiver implementer");
            }
        }
    }

    function _doSafeBatchTransferAcceptanceCheck(
        address operator,
        address from,
        address to,
        uint256[] memory ids,
        uint256[] memory amounts,
        bytes memory data
    ) private {
        if (to.isContract()) {
            try IERC1155Receiver(to).onERC1155BatchReceived(operator, from, ids, amounts, data) returns (
                bytes4 response
            ) {
                if (response != IERC1155Receiver.onERC1155BatchReceived.selector) {
                    revert("ERC1155: ERC1155Receiver rejected tokens");
                }
            } catch Error(string memory reason) {
                revert(reason);
            } catch {
                revert("ERC1155: transfer to non ERC1155Receiver implementer");
            }
        }
    }

    function _asSingletonArray(uint256 element) private pure returns (uint256[] memory) {
        uint256[] memory array = new uint256[](1);
        array[0] = element;

        return array;
    }
}

// File: @openzeppelin/contracts/token/ERC1155/IERC1155.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC1155/IERC1155.sol)

pragma solidity ^0.8.0;

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

/**
 * @dev Required interface of an ERC1155 compliant contract, as defined in the
 * https://eips.ethereum.org/EIPS/eip-1155[EIP].
 *
 * _Available since v3.1._
 */
interface IERC1155 is IERC165 {
    /**
     * @dev Emitted when `value` tokens of token type `id` are transferred from `from` to `to` by `operator`.
     */
    event TransferSingle(address indexed operator, address indexed from, address indexed to, uint256 id, uint256 value);

    /**
     * @dev Equivalent to multiple {TransferSingle} events, where `operator`, `from` and `to` are the same for all
     * transfers.
     */
    event TransferBatch(
        address indexed operator,
        address indexed from,
        address indexed to,
        uint256[] ids,
        uint256[] values
    );

    /**
     * @dev Emitted when `account` grants or revokes permission to `operator` to transfer their tokens, according to
     * `approved`.
     */
    event ApprovalForAll(address indexed account, address indexed operator, bool approved);

    /**
     * @dev Emitted when the URI for token type `id` changes to `value`, if it is a non-programmatic URI.
     *
     * If an {URI} event was emitted for `id`, the standard
     * https://eips.ethereum.org/EIPS/eip-1155#metadata-extensions[guarantees] that `value` will equal the value
     * returned by {IERC1155MetadataURI-uri}.
     */
    event URI(string value, uint256 indexed id);

    /**
     * @dev Returns the amount of tokens of token type `id` owned by `account`.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     */
    function balanceOf(address account, uint256 id) external view returns (uint256);

    /**
     * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {balanceOf}.
     *
     * Requirements:
     *
     * - `accounts` and `ids` must have the same length.
     */
    function balanceOfBatch(address[] calldata accounts, uint256[] calldata ids)
        external
        view
        returns (uint256[] memory);

    /**
     * @dev Grants or revokes permission to `operator` to transfer the caller's tokens, according to `approved`,
     *
     * Emits an {ApprovalForAll} event.
     *
     * Requirements:
     *
     * - `operator` cannot be the caller.
     */
    function setApprovalForAll(address operator, bool approved) external;

    /**
     * @dev Returns true if `operator` is approved to transfer ``account``'s tokens.
     *
     * See {setApprovalForAll}.
     */
    function isApprovedForAll(address account, address operator) external view returns (bool);

    /**
     * @dev Transfers `amount` tokens of token type `id` from `from` to `to`.
     *
     * Emits a {TransferSingle} event.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - If the caller is not `from`, it must have been approved to spend ``from``'s tokens via {setApprovalForAll}.
     * - `from` must have a balance of tokens of type `id` of at least `amount`.
     * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155Received} and return the
     * acceptance magic value.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 id,
        uint256 amount,
        bytes calldata data
    ) external;

    /**
     * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {safeTransferFrom}.
     *
     * Emits a {TransferBatch} event.
     *
     * Requirements:
     *
     * - `ids` and `amounts` must have the same length.
     * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155BatchReceived} and return the
     * acceptance magic value.
     */
    function safeBatchTransferFrom(
        address from,
        address to,
        uint256[] calldata ids,
        uint256[] calldata amounts,
        bytes calldata data
    ) external;
}

// File: @openzeppelin/contracts/token/ERC1155/IERC1155Receiver.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC1155/IERC1155Receiver.sol)

pragma solidity ^0.8.0;

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

/**
 * @dev _Available since v3.1._
 */
interface IERC1155Receiver is IERC165 {
    /**
     * @dev Handles the receipt of a single ERC1155 token type. This function is
     * called at the end of a `safeTransferFrom` after the balance has been updated.
     *
     * NOTE: To accept the transfer, this must return
     * `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))`
     * (i.e. 0xf23a6e61, or its own function selector).
     *
     * @param operator The address which initiated the transfer (i.e. msg.sender)
     * @param from The address which previously owned the token
     * @param id The ID of the token being transferred
     * @param value The amount of tokens being transferred
     * @param data Additional data with no specified format
     * @return `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))` if transfer is allowed
     */
    function onERC1155Received(
        address operator,
        address from,
        uint256 id,
        uint256 value,
        bytes calldata data
    ) external returns (bytes4);

    /**
     * @dev Handles the receipt of a multiple ERC1155 token types. This function
     * is called at the end of a `safeBatchTransferFrom` after the balances have
     * been updated.
     *
     * NOTE: To accept the transfer(s), this must return
     * `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))`
     * (i.e. 0xbc197c81, or its own function selector).
     *
     * @param operator The address which initiated the batch transfer (i.e. msg.sender)
     * @param from The address which previously owned the token
     * @param ids An array containing ids of each token being transferred (order and length must match values array)
     * @param values An array containing amounts of each token being transferred (order and length must match ids array)
     * @param data Additional data with no specified format
     * @return `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))` if transfer is allowed
     */
    function onERC1155BatchReceived(
        address operator,
        address from,
        uint256[] calldata ids,
        uint256[] calldata values,
        bytes calldata data
    ) external returns (bytes4);
}

// File: @openzeppelin/contracts/token/ERC1155/extensions/IERC1155MetadataURI.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC1155/extensions/IERC1155MetadataURI.sol)

pragma solidity ^0.8.0;

import "../IERC1155.sol";

/**
 * @dev Interface of the optional ERC1155MetadataExtension interface, as defined
 * in the https://eips.ethereum.org/EIPS/eip-1155#metadata-extensions[EIP].
 *
 * _Available since v3.1._
 */
interface IERC1155MetadataURI is IERC1155 {
    /**
     * @dev Returns the URI for token type `id`.
     *
     * If the `\{id\}` substring is present in the URI, it must be replaced by
     * clients with the actual token type ID.
     */
    function uri(uint256 id) external view returns (string memory);
}

// File: @openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/ERC721Enumerable.sol)

pragma solidity ^0.8.0;

import "../ERC721.sol";
import "./IERC721Enumerable.sol";

/**
 * @dev This implements an optional extension of {ERC721} defined in the EIP that adds
 * enumerability of all the token ids in the contract as well as all token ids owned by each
 * account.
 */
abstract contract ERC721Enumerable is ERC721, IERC721Enumerable {
    // Mapping from owner to list of owned token IDs
    mapping(address => mapping(uint256 => uint256)) private _ownedTokens;

    // Mapping from token ID to index of the owner tokens list
    mapping(uint256 => uint256) private _ownedTokensIndex;

    // Array with all token ids, used for enumeration
    uint256[] private _allTokens;

    // Mapping from token id to position in the allTokens array
    mapping(uint256 => uint256) private _allTokensIndex;

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165, ERC721) returns (bool) {
        return interfaceId == type(IERC721Enumerable).interfaceId || super.supportsInterface(interfaceId);
    }

    /**
     * @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.
     */
    function tokenOfOwnerByIndex(address owner, uint256 index) public view virtual override returns (uint256) {
        require(index < ERC721.balanceOf(owner), "ERC721Enumerable: owner index out of bounds");
        return _ownedTokens[owner][index];
    }

    /**
     * @dev See {IERC721Enumerable-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _allTokens.length;
    }

    /**
     * @dev See {IERC721Enumerable-tokenByIndex}.
     */
    function tokenByIndex(uint256 index) public view virtual override returns (uint256) {
        require(index < ERC721Enumerable.totalSupply(), "ERC721Enumerable: global index out of bounds");
        return _allTokens[index];
    }

    /**
     * @dev Hook that is called before any token transfer. This includes minting
     * and burning.
     *
     * 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, ``from``'s `tokenId` will be burned.
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 tokenId
    ) internal virtual override {
        super._beforeTokenTransfer(from, to, tokenId);

        if (from == address(0)) {
            _addTokenToAllTokensEnumeration(tokenId);
        } else if (from != to) {
            _removeTokenFromOwnerEnumeration(from, tokenId);
        }
        if (to == address(0)) {
            _removeTokenFromAllTokensEnumeration(tokenId);
        } else if (to != from) {
            _addTokenToOwnerEnumeration(to, tokenId);
        }
    }

    /**
     * @dev Private function to add a token to this extension's ownership-tracking data structures.
     * @param to address representing the new owner of the given token ID
     * @param tokenId uint256 ID of the token to be added to the tokens list of the given address
     */
    function _addTokenToOwnerEnumeration(address to, uint256 tokenId) private {
        uint256 length = ERC721.balanceOf(to);
        _ownedTokens[to][length] = tokenId;
        _ownedTokensIndex[tokenId] = length;
    }

    /**
     * @dev Private function to add a token to this extension's token tracking data structures.
     * @param tokenId uint256 ID of the token to be added to the tokens list
     */
    function _addTokenToAllTokensEnumeration(uint256 tokenId) private {
        _allTokensIndex[tokenId] = _allTokens.length;
        _allTokens.push(tokenId);
    }

    /**
     * @dev Private function to remove a token from this extension's ownership-tracking data structures. Note that
     * while the token is not assigned a new owner, the `_ownedTokensIndex` mapping is _not_ updated: this allows for
     * gas optimizations e.g. when performing a transfer operation (avoiding double writes).
     * This has O(1) time complexity, but alters the order of the _ownedTokens array.
     * @param from address representing the previous owner of the given token ID
     * @param tokenId uint256 ID of the token to be removed from the tokens list of the given address
     */
    function _removeTokenFromOwnerEnumeration(address from, uint256 tokenId) private {
        // To prevent a gap in from's tokens array, we store the last token in the index of the token to delete, and
        // then delete the last slot (swap and pop).

        uint256 lastTokenIndex = ERC721.balanceOf(from) - 1;
        uint256 tokenIndex = _ownedTokensIndex[tokenId];

        // When the token to delete is the last token, the swap operation is unnecessary
        if (tokenIndex != lastTokenIndex) {
            uint256 lastTokenId = _ownedTokens[from][lastTokenIndex];

            _ownedTokens[from][tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token
            _ownedTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index
        }

        // This also deletes the contents at the last position of the array
        delete _ownedTokensIndex[tokenId];
        delete _ownedTokens[from][lastTokenIndex];
    }

    /**
     * @dev Private function to remove a token from this extension's token tracking data structures.
     * This has O(1) time complexity, but alters the order of the _allTokens array.
     * @param tokenId uint256 ID of the token to be removed from the tokens list
     */
    function _removeTokenFromAllTokensEnumeration(uint256 tokenId) private {
        // To prevent a gap in the tokens array, we store the last token in the index of the token to delete, and
        // then delete the last slot (swap and pop).

        uint256 lastTokenIndex = _allTokens.length - 1;
        uint256 tokenIndex = _allTokensIndex[tokenId];

        // When the token to delete is the last token, the swap operation is unnecessary. However, since this occurs so
        // rarely (when the last minted token is burnt) that we still do the swap here to avoid the gas cost of adding
        // an 'if' statement (like in _removeTokenFromOwnerEnumeration)
        uint256 lastTokenId = _allTokens[lastTokenIndex];

        _allTokens[tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token
        _allTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index

        // This also deletes the contents at the last position of the array
        delete _allTokensIndex[tokenId];
        _allTokens.pop();
    }
}

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



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

pragma solidity ^0.8.0;

/**
 * @title Counters
 * @author Matt Condon (@shrugs)
 * @dev Provides counters that can only be incremented, decremented or reset. This can be used e.g. to track the number
 * of elements in a mapping, issuing ERC721 ids, or counting request ids.
 *
 * Include with `using Counters for Counters.Counter;`
 */
library Counters {
    struct Counter {
        // This variable should never be directly accessed by users of the library: interactions must be restricted to
        // the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add
        // this feature: see https://github.com/ethereum/solidity/issues/4637
        uint256 _value; // default: 0
    }

    function current(Counter storage counter) internal view returns (uint256) {
        return counter._value;
    }

    function increment(Counter storage counter) internal {
        unchecked {
            counter._value += 1;
        }
    }

    function decrement(Counter storage counter) internal {
        uint256 value = counter._value;
        require(value > 0, "Counter: decrement overflow");
        unchecked {
            counter._value = value - 1;
        }
    }

    function reset(Counter storage counter) internal {
        counter._value = 0;
    }
}

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



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

pragma solidity ^0.8.0;

import "./IERC721.sol";
import "./IERC721Receiver.sol";
import "./extensions/IERC721Metadata.sol";
import "../../utils/Address.sol";
import "../../utils/Context.sol";
import "../../utils/Strings.sol";
import "../../utils/introspection/ERC165.sol";

/**
 * @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
 * the Metadata extension, but not including the Enumerable extension, which is available separately as
 * {ERC721Enumerable}.
 */
contract ERC721 is Context, ERC165, IERC721, IERC721Metadata {
    using Address for address;
    using Strings for uint256;

    // Token name
    string private _name;

    // Token symbol
    string private _symbol;

    // Mapping from token ID to owner address
    mapping(uint256 => address) private _owners;

    // Mapping owner address to token count
    mapping(address => uint256) private _balances;

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

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

    /**
     * @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
        return
            interfaceId == type(IERC721).interfaceId ||
            interfaceId == type(IERC721Metadata).interfaceId ||
            super.supportsInterface(interfaceId);
    }

    /**
     * @dev See {IERC721-balanceOf}.
     */
    function balanceOf(address owner) public view virtual override returns (uint256) {
        require(owner != address(0), "ERC721: address zero is not a valid owner");
        return _balances[owner];
    }

    /**
     * @dev See {IERC721-ownerOf}.
     */
    function ownerOf(uint256 tokenId) public view virtual override returns (address) {
        address owner = _owners[tokenId];
        require(owner != address(0), "ERC721: invalid token ID");
        return owner;
    }

    /**
     * @dev See {IERC721Metadata-name}.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }

    /**
     * @dev See {IERC721Metadata-symbol}.
     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    /**
     * @dev See {IERC721Metadata-tokenURI}.
     */
    function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
        _requireMinted(tokenId);

        string memory baseURI = _baseURI();
        return bytes(baseURI).length > 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : "";
    }

    /**
     * @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, can be overridden in child contracts.
     */
    function _baseURI() internal view virtual returns (string memory) {
        return "";
    }

    /**
     * @dev See {IERC721-approve}.
     */
    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 token owner nor approved for all"
        );

        _approve(to, tokenId);
    }

    /**
     * @dev See {IERC721-getApproved}.
     */
    function getApproved(uint256 tokenId) public view virtual override returns (address) {
        _requireMinted(tokenId);

        return _tokenApprovals[tokenId];
    }

    /**
     * @dev See {IERC721-setApprovalForAll}.
     */
    function setApprovalForAll(address operator, bool approved) public virtual override {
        _setApprovalForAll(_msgSender(), operator, approved);
    }

    /**
     * @dev See {IERC721-isApprovedForAll}.
     */
    function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
        return _operatorApprovals[owner][operator];
    }

    /**
     * @dev See {IERC721-transferFrom}.
     */
    function transferFrom(
        address from,
        address to,
        uint256 tokenId
    ) public virtual override {
        //solhint-disable-next-line max-line-length
        require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner nor approved");

        _transfer(from, to, tokenId);
    }

    /**
     * @dev See {IERC721-safeTransferFrom}.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId
    ) public virtual override {
        safeTransferFrom(from, to, tokenId, "");
    }

    /**
     * @dev See {IERC721-safeTransferFrom}.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId,
        bytes memory data
    ) public virtual override {
        require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner nor approved");
        _safeTransfer(from, to, tokenId, data);
    }

    /**
     * @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.
     *
     * `data` is additional data, it has no specified format and it is sent in call to `to`.
     *
     * This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.
     * implement alternative mechanisms to perform token transfer, such as signature-based.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function _safeTransfer(
        address from,
        address to,
        uint256 tokenId,
        bytes memory data
    ) internal virtual {
        _transfer(from, to, tokenId);
        require(_checkOnERC721Received(from, to, tokenId, data), "ERC721: transfer to non ERC721Receiver implementer");
    }

    /**
     * @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 (`_mint`),
     * and stop existing when they are burned (`_burn`).
     */
    function _exists(uint256 tokenId) internal view virtual returns (bool) {
        return _owners[tokenId] != address(0);
    }

    /**
     * @dev Returns whether `spender` is allowed to manage `tokenId`.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    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);
    }

    /**
     * @dev Safely mints `tokenId` and transfers it to `to`.
     *
     * Requirements:
     *
     * - `tokenId` must not exist.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function _safeMint(address to, uint256 tokenId) internal virtual {
        _safeMint(to, tokenId, "");
    }

    /**
     * @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is
     * forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
     */
    function _safeMint(
        address to,
        uint256 tokenId,
        bytes memory data
    ) internal virtual {
        _mint(to, tokenId);
        require(
            _checkOnERC721Received(address(0), to, tokenId, data),
            "ERC721: transfer to non ERC721Receiver implementer"
        );
    }

    /**
     * @dev Mints `tokenId` and transfers it to `to`.
     *
     * WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible
     *
     * Requirements:
     *
     * - `tokenId` must not exist.
     * - `to` cannot be the zero address.
     *
     * Emits a {Transfer} event.
     */
    function _mint(address to, uint256 tokenId) internal virtual {
        require(to != address(0), "ERC721: mint to the zero address");
        require(!_exists(tokenId), "ERC721: token already minted");

        _beforeTokenTransfer(address(0), to, tokenId);

        _balances[to] += 1;
        _owners[tokenId] = to;

        emit Transfer(address(0), to, tokenId);

        _afterTokenTransfer(address(0), to, tokenId);
    }

    /**
     * @dev Destroys `tokenId`.
     * The approval is cleared when the token is burned.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     *
     * Emits a {Transfer} event.
     */
    function _burn(uint256 tokenId) internal virtual {
        address owner = ERC721.ownerOf(tokenId);

        _beforeTokenTransfer(owner, address(0), tokenId);

        // Clear approvals
        _approve(address(0), tokenId);

        _balances[owner] -= 1;
        delete _owners[tokenId];

        emit Transfer(owner, address(0), tokenId);

        _afterTokenTransfer(owner, address(0), tokenId);
    }

    /**
     * @dev Transfers `tokenId` from `from` to `to`.
     *  As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     *
     * Emits a {Transfer} event.
     */
    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");

        _beforeTokenTransfer(from, to, tokenId);

        // Clear approvals from the previous owner
        _approve(address(0), tokenId);

        _balances[from] -= 1;
        _balances[to] += 1;
        _owners[tokenId] = to;

        emit Transfer(from, to, tokenId);

        _afterTokenTransfer(from, to, tokenId);
    }

    /**
     * @dev Approve `to` to operate on `tokenId`
     *
     * Emits an {Approval} event.
     */
    function _approve(address to, uint256 tokenId) internal virtual {
        _tokenApprovals[tokenId] = to;
        emit Approval(ERC721.ownerOf(tokenId), to, tokenId);
    }

    /**
     * @dev Approve `operator` to operate on all of `owner` tokens
     *
     * Emits an {ApprovalForAll} event.
     */
    function _setApprovalForAll(
        address owner,
        address operator,
        bool approved
    ) internal virtual {
        require(owner != operator, "ERC721: approve to caller");
        _operatorApprovals[owner][operator] = approved;
        emit ApprovalForAll(owner, operator, approved);
    }

    /**
     * @dev Reverts if the `tokenId` has not been minted yet.
     */
    function _requireMinted(uint256 tokenId) internal view virtual {
        require(_exists(tokenId), "ERC721: invalid token ID");
    }

    /**
     * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.
     * The call is not executed if the target address is not a contract.
     *
     * @param from address representing the previous owner of the given token ID
     * @param to target address that will receive the tokens
     * @param tokenId uint256 ID of the token to be transferred
     * @param data bytes optional data to send along with the call
     * @return bool whether the call correctly returned the expected magic value
     */
    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 {
                    /// @solidity memory-safe-assembly
                    assembly {
                        revert(add(32, reason), mload(reason))
                    }
                }
            }
        } else {
            return true;
        }
    }

    /**
     * @dev Hook that is called before any token transfer. This includes minting
     * and burning.
     *
     * 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, ``from``'s `tokenId` will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 tokenId
    ) internal virtual {}

    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _afterTokenTransfer(
        address from,
        address to,
        uint256 tokenId
    ) internal virtual {}
}