// File: contracts/Owland.sol



// SPDX-License-Identifier: UNLICENSED

pragma solidity ^0.8.0;

import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/utils/Counters.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/utils/math/SafeCast.sol";

contract DarkOwlsEstate is ERC721, Ownable {
    using Counters for Counters.Counter;
    using SafeCast for uint256;
    Counters.Counter public totalSupply;

    DarkOwls public darkowls;

    string public baseURI;

    uint256 public cost = 0.02 ether;
    uint256 public costRare = 0.08 ether;
    uint256 public maxPublicMint = 4;
    bool public paused = false;
    bool public publicMinting = false;
    bool public rareByAllowance = false;
    bool public rareByPublic = false;
    bool public isFree = true;
    mapping(uint256 => bool) public typeAPlots;
    mapping(uint256 => bool) public typeBPlots;
    mapping(address => uint256) public rareAllowance;
    mapping(uint => bool) public hasMinted;
    address public stakingAddress;

    //staking params
    bool public stakePaused = true;
    mapping(uint256 => bool) public staked;
    struct stakeDetails {
        uint16 depositCycle;
        uint16 withdrawCycle;
        uint256 claimedRewards;
    }
    mapping(uint256 => stakeDetails) public detailsById;
    uint256 public startTimestamp;
    uint32 public immutable cycleLengthInSeconds;
    uint256 public rewardsPerCycle;
    address tokenAddress;
    uint16 public lockedCycles;

    event rewardsClaimed(uint256 amount, uint256 timestamp, address user);

    uint256 internal constant GRID_SIZE = 50;

    constructor() ERC721 ("Dark Owls Estate", "EOWL") {
        uint16[36] memory aTypePlots = [0, 14, 24, 25, 34, 49, 459, 469, 479, 489, 700, 749, 959, 989, 1200, 1224, 1225, 1249, 1250, 1274, 1275, 1299, 1459, 1489, 1700, 1749, 1959, 1969, 1979, 1989, 2450, 2464, 2474, 2475, 2484, 2499];
        for (uint256 i = 0; i < aTypePlots.length; i++) {
            typeAPlots[aTypePlots[i]] = true;
        }
        uint16[242] memory bTypePlots = [1, 2, 23, 26, 47, 48, 50, 51, 64, 74, 75, 84, 98, 99, 100, 149, 408, 409, 410, 418, 419, 420, 428, 429, 430, 438, 439, 440, 458, 460, 468, 470, 478, 480, 488, 490, 508, 509, 510, 518, 519, 520, 528, 529, 530, 538, 539, 540, 701, 748, 908, 909, 910, 938, 939, 940, 958, 960, 974, 975, 988, 990, 1008, 1009, 1010, 1020, 1021, 1022, 1023, 1024, 1025, 1026, 1027, 1028, 1029, 1038, 1039, 1040, 1070, 1071, 1072, 1073, 1074, 1075, 1076, 1077, 1078, 1079, 1120, 1121, 1122, 1123, 1124, 1125, 1126, 1127, 1128, 1129, 1150, 1170, 1171, 1172, 1173, 1174, 1175, 1176, 1177, 1178, 1179, 1199, 1201, 1219, 1220, 1221, 1222, 1223, 1226, 1227, 1228, 1229, 1230, 1248, 1251, 1269, 1270, 1271, 1272, 1273, 1276, 1277, 1278, 1279, 1280, 1298, 1300, 1320, 1321, 1322, 1323, 1324, 1325, 1326, 1327, 1328, 1329, 1349, 1370, 1371, 1372, 1373, 1374, 1375, 1376, 1377, 1378, 1379, 1408, 1409, 1410, 1420, 1421, 1422, 1423, 1424, 1425, 1426, 1427, 1428, 1429, 1438, 1439, 1440, 1458, 1460, 1470, 1471, 1472, 1473, 1474, 1475, 1476, 1477, 1478, 1479, 1488, 1490, 1508, 1509, 1510, 1538, 1539, 1540, 1701, 1748, 1908, 1909, 1910, 1918, 1919, 1920, 1928, 1929, 1930, 1938, 1939, 1940, 1958, 1960, 1968, 1970, 1978, 1980, 1988, 1990, 2008, 2009, 2010, 2018, 2019, 2020, 2028, 2029, 2030, 2038, 2039, 2040, 2350, 2399, 2400, 2401, 2414, 2424, 2425, 2434, 2448, 2449, 2451, 2452, 2473, 2476, 2497, 2498];
        for (uint256 i = 0; i < bTypePlots.length; i++) {
            typeBPlots[bTypePlots[i]] = true;
        }

        baseURI = "ipfs://Qme867emMNf2U96oZALPqG51YU6pKzaGBnGV9iQQod7WVW/";

        //staking
        startTimestamp = block.timestamp;
        cycleLengthInSeconds = 86400; // 1 day
        rewardsPerCycle = 0.1 * 10**18; // 0.1 tokens per day 
        lockedCycles = 30; // 30 days
        tokenAddress = 0xD5d86FC8d5C0Ea1aC1Ac5Dfab6E529c9967a45E9;
    }

    function _baseURI() internal view virtual override returns (string memory) {
        return baseURI;
    }

// Manages the id and retrieves the coordinates of the Land Plot (x,y)
    function width() external pure returns(uint256) {
        return GRID_SIZE;
    }
    function height() external pure returns(uint256) {
        return GRID_SIZE;
    }
    /// x coordinate of Land token
    function x(uint256 id) public pure returns(uint256) {
        return id % GRID_SIZE;
    }
    /// y coordinate of Land token
    function y(uint256 id) public pure returns(uint256) {
        return id / GRID_SIZE;
    }
    /// ID for x and y coordinates
    function getTokenIdByCoordinates(uint256 _x, uint256 _y) public pure returns(uint256) {
        require(_x < GRID_SIZE && _y < GRID_SIZE);
        return _x + _y * GRID_SIZE;
    }

//Returns true if DOWL had already minted a DarkOwlsEstate
    function checkOwl(uint256 _owlId) public view returns (bool){
        return hasMinted[_owlId];
    }

    function mintByCoordinates(uint256 _x, uint256 _y, uint256 _owlId, bool _stake) external payable {
        require(!paused, "Pause");
        if (!isFree) {
            require(msg.value >= cost);
        }
        // Check if Owls Ids have minted a Land and is Owned by msg sender
        require(hasMinted[_owlId] == false, "Invalid Owl");
        require(darkowls.ownerOf(_owlId) == msg.sender, "Not owner");
        hasMinted[_owlId] = true;
        // Check if coordinates are inside grid
        require(_x < GRID_SIZE && _y < GRID_SIZE, "out of bounds");

        _mintLand(_x + _y * GRID_SIZE, _stake);
    }

    function mintLands(uint256[] calldata _tokenIds, uint256[] calldata _owlIds, bool _stake) external payable {
        require(!paused, "Pause");
        require(_tokenIds.length == _owlIds.length, "#lands = #owls");
        require(_owlIds.length > 0, ">0"); // see if required
        if (!isFree) {
            require(msg.value >= cost * _owlIds.length, "Pay me!");
        }
        
        // Check if Owls Ids have minted a Land and is Owned by msg sender
        for (uint256 i = 0; i < _owlIds.length; i++) {
            require(hasMinted[_owlIds[i]] == false, "Invalid Owl");
            require(darkowls.ownerOf(_owlIds[i]) == msg.sender, "Not owner");
            hasMinted[_owlIds[i]] = true;
        }

        // Check if coordinates are inside grid
        for (uint256 i = 0; i < _tokenIds.length; i++) {
            uint256 _tokenId = _tokenIds[i];
            require(x(_tokenId) < GRID_SIZE && y(_tokenId) < GRID_SIZE, "out of bounds");
        }
        
        _mintLand(_tokenIds, _stake);
    }

    function mintEpicPlotsOwner(address _to, uint256[] calldata _tokenIds) external onlyOwner {
        require(_tokenIds.length > 0, ">0"); // see if required

        // Requires is reserved plot and mints to _to
        for (uint256 i = 0; i < _tokenIds.length; i++) {
            uint256 _tokenId = _tokenIds[i];
            require(typeAPlots[_tokenId], "Epic");
            _safeMint(_to, _tokenId);
            totalSupply.increment();
        }
    }

    function mintRarePlotsOwner(address _to, uint256[] calldata _tokenIds) external onlyOwner {
        require(_tokenIds.length > 0, ">0"); // see if required

        // Requires is reserved plot and mints to _to
        for (uint256 i = 0; i < _tokenIds.length; i++) {
            uint256 _tokenId = _tokenIds[i];
            require(typeBPlots[_tokenId], "Rare");
            _safeMint(_to, _tokenId);
            totalSupply.increment();
        }
    }

    function mintRarePlots(uint256[] calldata _tokenIds, bool _stake) external payable {
        address sender = _msgSender();
        require(!paused, "Pause");
        require((rareByAllowance && !rareByPublic) || (!rareByAllowance && rareByPublic), "R");
        require(_tokenIds.length > 0, ">0");
        require(msg.value >= costRare * _tokenIds.length);

        if (rareByPublic) {
            for (uint256 i = 0; i < _tokenIds.length; i++) {
                uint256 _tokenId = _tokenIds[i];
                require(typeBPlots[_tokenId], "Rare");

                if (!_stake) {
                    _safeMint(msg.sender, _tokenId);
                } else {
                    require(stakingAddress != address(0), "no staking");
                    _safeMint(stakingAddress, _tokenId, abi.encode(msg.sender)); // Mint to the staking address
                }
                totalSupply.increment();
            }
        }
        
        if (rareByAllowance) {
            for (uint256 i = 0; i < _tokenIds.length; i++) {
                require(rareAllowance[sender] > 0, "maxed allowed amount");
                uint256 _tokenId = _tokenIds[i];
                require(typeBPlots[_tokenId], "Rare");

                if (!_stake) {
                    _safeMint(msg.sender, _tokenId);
                } else {
                    require(stakingAddress != address(0), "no staking");
                    _safeMint(stakingAddress, _tokenId, abi.encode(msg.sender)); // Mint to the staking address
                }
                rareAllowance[sender]--;
                totalSupply.increment();
            }
        }
    }

    function mintByCoordinatesPublic(uint256 _x, uint256 _y, bool _stake) external payable {
        require(!paused, "Pause");
        require(publicMinting, "Public minting disabled");
        require(msg.value >= cost);
        
        // Check if coordinates are inside grid
        require(_x < GRID_SIZE && _y < GRID_SIZE);

        _mintLand(_x + _y * GRID_SIZE, _stake);
    }

    function mintLandsPublic(uint256[] calldata _tokenIds, bool _stake) external payable {
        require(!paused, "Pause");
        require(publicMinting, "Public minting disabled");
        require(_tokenIds.length > 0, ">0");
        require(_tokenIds.length < maxPublicMint + 1, "Exceded the maximum minting amount by one Tx");
        require(msg.value >= cost * _tokenIds.length);

        // Check if coordinates are inside grid
        for (uint256 i = 0; i < _tokenIds.length; i++) {
            uint256 _tokenId = _tokenIds[i];
            require(x(_tokenId) < GRID_SIZE && y(_tokenId) < GRID_SIZE, "Coordinates out of bounds");
        }
        
        _mintLand(_tokenIds, _stake);
    }

    function _mintLand(uint256 _tokenId, bool _stake) internal virtual {
        uint256[] memory _tokenIds = new uint256[](1);
        _tokenIds[0] = _tokenId;
        _mintLand(_tokenIds, _stake);
    }

    function _mintLand(uint256[] memory _tokenIds, bool _stake) internal virtual {
        for (uint256 i = 0; i < _tokenIds.length; i++) {
            uint256 _tokenId = _tokenIds[i];
            require(!typeAPlots[_tokenId], "Common");
            require(!typeBPlots[_tokenId], "Common");
            if (!_stake) {
                _safeMint(msg.sender, _tokenId);
            } else {
                require(stakingAddress != address(0), "no staking");
                _safeMint(stakingAddress, _tokenId, abi.encode(msg.sender)); // Mint to the staking address
            }
            
            totalSupply.increment();
        }
    }

    //Staking functions
    function stakeLand(uint256 tokenID) public {
        require(!stakePaused, "Stake paused");
        require(_isApprovedOrOwner(msg.sender, tokenID));
        require(!staked[tokenID]);
        require(detailsById[tokenID].withdrawCycle != _getCycle(block.timestamp));
        staked[tokenID] = true;
        detailsById[tokenID].depositCycle = _getCycle(block.timestamp);
    }

    function batchStakeLands(uint256[] memory tokensIds) external {
        for (uint256 i; i < tokensIds.length; i++) {
            uint256 tokenID = tokensIds[i];
            stakeLand(tokenID);
        }
    }

    function unstakeLand(uint256 tokenID) external {
        require(ownerOf(tokenID) == msg.sender, "NOT_TOKEN_OWNER");
        require(staked[tokenID]);
        require(detailsById[tokenID].depositCycle + lockedCycles <= _getCycle(block.timestamp), "Lock time!");
        if (getRewards(tokenID) > 0) {
            claimSingleReward(tokenID);
        }
        staked[tokenID] = false;
        detailsById[tokenID] = stakeDetails({
            depositCycle: 0,
            withdrawCycle: _getCycle(block.timestamp),
            claimedRewards: 0
        });
    }

    function batchUnstakeLands(uint256[] memory tokensIds) external {
        uint256 amount;
        for (uint256 i; i < tokensIds.length; i++) {
            uint256 tokenID = tokensIds[i];
            amount += getRewards(tokenID);
        }
        if (amount > 0) {
            claimRewards(tokensIds);
        }
        for (uint256 i; i < tokensIds.length; i++) {
            uint256 tokenID = tokensIds[i];
            require(ownerOf(tokenID) == msg.sender, "NOT_TOKEN_OWNER");
            require(staked[tokenID]);
            require(detailsById[tokenID].depositCycle + lockedCycles <= _getCycle(block.timestamp), "Lock time!");
            staked[tokenID] = false;
            detailsById[tokenID] = stakeDetails({
                depositCycle: 0,
                withdrawCycle: _getCycle(block.timestamp),
                claimedRewards: 0
            });
        }
    }

    function claimSingleReward(uint256 tokenID) public {
        require(ownerOf(tokenID) == msg.sender, "NOT_TOKEN_OWNER");
        require(staked[tokenID]);
        uint256 amount = getRewards(tokenID);
        require(amount > 0, "NO_REWARDS_AVAILABLE");
        detailsById[tokenID].claimedRewards += amount;
        IERC20(tokenAddress).transfer(msg.sender, amount);

        emit rewardsClaimed(amount, block.timestamp, msg.sender);
    }

    function claimRewards(uint256[] memory tokensIds) public {
        uint256 amount;
        for (uint256 i; i < tokensIds.length; i++) {
            uint256 tokenID = tokensIds[i];
            require(ownerOf(tokenID) == msg.sender, "NOT_TOKEN_OWNER");
            require(staked[tokenID]);
            amount += getRewards(tokenID);
            detailsById[tokenID].claimedRewards += getRewards(tokenID);
        }
        require(amount > 0, "NO_REWARDS_AVAILABLE");
        IERC20(tokenAddress).transfer(msg.sender, amount);

        emit rewardsClaimed(amount, block.timestamp, msg.sender);
    }

    function getRewards(uint256 tokenID) public view returns (uint256 amount) {
        require(detailsById[tokenID].depositCycle > 0);
        uint16 cyclesSinceDeposit = _getCycle(block.timestamp) - detailsById[tokenID].depositCycle;
        amount = (rewardsPerCycle * cyclesSinceDeposit) - detailsById[tokenID].claimedRewards;
    }

    function _getCycle(uint256 timestamp) internal view returns (uint16) {
        require(timestamp >= startTimestamp, "NftStaking: timestamp preceeds contract start");
        return (((timestamp - startTimestamp) / uint256(cycleLengthInSeconds)) + 1).toUint16();
    }

    // returns array of all NFTs owned by _address
    function tokensOfOwner(address _address) external view returns(uint256[] memory) {
        require(balanceOf(_address) > 0, "no tks");
        uint256[] memory _tokensOfOwner = new uint256[](balanceOf(_address));
        uint256 j = 0;
        uint256 i = 0;
        while (i < balanceOf(_address)) {
            if (_exists(j)) {
                if (ownerOf(j) == _address) {
                    _tokensOfOwner[i] = j;
                    i++;
                }
            }
            j++;
        }
        return _tokensOfOwner;
    }

    // returns array of all minted plots
    function mintedLands() external view returns (uint256[] memory) {
        uint256[] memory _mintedIds = new uint256[](totalSupply.current());
        uint256 j = 0;
        uint256 i = 0;
        while (i < totalSupply.current()) {
            if (_exists(j)) {
                _mintedIds[i] = j;
                i++;
            }
            j++;
        }
        return _mintedIds;
    }

    /* ---- onlyOwner functions ---- */

    function setCost(uint256 _cost) external onlyOwner {
        cost = _cost;
    }
    function setCostRare(uint256 _cost) external onlyOwner {
        costRare = _cost;
    }
    function setPause(bool _state) public onlyOwner {
        paused = _state;
    }
    function setStakePaused(bool _state) public onlyOwner {
        stakePaused = _state;
    }
    function setIsFree(bool _state) public onlyOwner {
        isFree = _state;
    }
    function setDarkOwlsAddress(address _darkowlsAddress) public onlyOwner {
        darkowls = DarkOwls(_darkowlsAddress);
    }
    function setBaseURI(string memory _newBaseURI) public onlyOwner {
        baseURI = _newBaseURI;
    }
    function setStakingAddress(address _stakingAddress) external onlyOwner {
        stakingAddress = _stakingAddress;
    }
    function setPublicMinting(bool _publicMinting) public onlyOwner {
        publicMinting = _publicMinting;
    }
    function setRareByAllowance(bool _rareByAllowance) public onlyOwner {
        rareByAllowance = _rareByAllowance;
        require(!(rareByAllowance && rareByPublic), "rare by allowance and public true");
    }
    function setRareByPublic(bool _rareByPublic) public onlyOwner {
        rareByPublic = _rareByPublic;
        require(!(rareByAllowance && rareByPublic), "rare by allowance and public true");
    }
    function setMaxPublicMint(uint256 _maxPublicMint) external onlyOwner {
        maxPublicMint = _maxPublicMint;
    }
    function addRareAllowanceToAddress(address _to, uint256 _allowance) external onlyOwner {
        uint256 currentAllowance = rareAllowance[_to];
        rareAllowance[_to] = currentAllowance + _allowance;
    }
    function withdraw() public payable onlyOwner {
        require(payable(msg.sender).send(address(this).balance));
    }
    function setRewardsPerCycle(uint256 _rewardsPerCycle) external onlyOwner {
        rewardsPerCycle = _rewardsPerCycle;
    }
    function setTokenAddress(address _tokenAddress) external onlyOwner {
        tokenAddress = _tokenAddress;
    }
    function setLockedCycles(uint16 _lockedCycles) external onlyOwner {
        lockedCycles = _lockedCycles;
    }
    function retrieveTokens(address _to, uint256 _amount, address _tokenAddress) external onlyOwner {
        require(IERC20(_tokenAddress).transfer(_to, _amount));
    }


    // Allows staking contract to make transfer on behalf of owner
    function transferFrom(address from, address to, uint256 tokenId) public virtual override {
        address sender = _msgSender();
        require(_isApprovedOrOwner(sender, tokenId) || sender == stakingAddress, "ERC721: transfer caller is not owner nor approved");
        _transfer(from, to, tokenId);
    }
    function _beforeTokenTransfer(address from, address to, uint256 tokenId) internal override {
        require(!staked[tokenId], "staked Land");
        super._beforeTokenTransfer(from, to, tokenId);
    }
}

interface DarkOwls {
        function ownerOf(uint256 tokenId) external view returns (address);
}
// File: @openzeppelin/contracts/token/ERC721/ERC721.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (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: balance query for the zero address");
        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: owner query for nonexistent token");
        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) {
        require(_exists(tokenId), "ERC721Metadata: URI query for nonexistent token");

        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 virtual override {
        address owner = ERC721.ownerOf(tokenId);
        require(to != owner, "ERC721: approval to current owner");

        require(
            _msgSender() == owner || isApprovedForAll(owner, _msgSender()),
            "ERC721: approve caller is not owner nor approved for all"
        );

        _approve(to, tokenId);
    }

    /**
     * @dev See {IERC721-getApproved}.
     */
    function getApproved(uint256 tokenId) public view virtual override returns (address) {
        require(_exists(tokenId), "ERC721: approved query for nonexistent token");

        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: transfer caller is not 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: transfer caller is not 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) {
        require(_exists(tokenId), "ERC721: operator query for nonexistent token");
        address owner = ERC721.ownerOf(tokenId);
        return (spender == owner || getApproved(tokenId) == spender || isApprovedForAll(owner, 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 a {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 a {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 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 {
                    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 {}
}

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

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

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

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

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

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

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

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

// 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/access/Ownable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (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 Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

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

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

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

// File: @openzeppelin/contracts/utils/math/SafeCast.sol



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

pragma solidity ^0.8.0;

/**
 * @dev Wrappers over Solidity's uintXX/intXX casting operators with added overflow
 * checks.
 *
 * Downcasting from uint256/int256 in Solidity does not revert on overflow. This can
 * easily result in undesired exploitation or bugs, since developers usually
 * assume that overflows raise errors. `SafeCast` restores this intuition by
 * reverting the transaction when such an operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 *
 * Can be combined with {SafeMath} and {SignedSafeMath} to extend it to smaller types, by performing
 * all math on `uint256` and `int256` and then downcasting.
 */
library SafeCast {
    /**
     * @dev Returns the downcasted uint224 from uint256, reverting on
     * overflow (when the input is greater than largest uint224).
     *
     * Counterpart to Solidity's `uint224` operator.
     *
     * Requirements:
     *
     * - input must fit into 224 bits
     */
    function toUint224(uint256 value) internal pure returns (uint224) {
        require(value <= type(uint224).max, "SafeCast: value doesn't fit in 224 bits");
        return uint224(value);
    }

    /**
     * @dev Returns the downcasted uint128 from uint256, reverting on
     * overflow (when the input is greater than largest uint128).
     *
     * Counterpart to Solidity's `uint128` operator.
     *
     * Requirements:
     *
     * - input must fit into 128 bits
     */
    function toUint128(uint256 value) internal pure returns (uint128) {
        require(value <= type(uint128).max, "SafeCast: value doesn't fit in 128 bits");
        return uint128(value);
    }

    /**
     * @dev Returns the downcasted uint96 from uint256, reverting on
     * overflow (when the input is greater than largest uint96).
     *
     * Counterpart to Solidity's `uint96` operator.
     *
     * Requirements:
     *
     * - input must fit into 96 bits
     */
    function toUint96(uint256 value) internal pure returns (uint96) {
        require(value <= type(uint96).max, "SafeCast: value doesn't fit in 96 bits");
        return uint96(value);
    }

    /**
     * @dev Returns the downcasted uint64 from uint256, reverting on
     * overflow (when the input is greater than largest uint64).
     *
     * Counterpart to Solidity's `uint64` operator.
     *
     * Requirements:
     *
     * - input must fit into 64 bits
     */
    function toUint64(uint256 value) internal pure returns (uint64) {
        require(value <= type(uint64).max, "SafeCast: value doesn't fit in 64 bits");
        return uint64(value);
    }

    /**
     * @dev Returns the downcasted uint32 from uint256, reverting on
     * overflow (when the input is greater than largest uint32).
     *
     * Counterpart to Solidity's `uint32` operator.
     *
     * Requirements:
     *
     * - input must fit into 32 bits
     */
    function toUint32(uint256 value) internal pure returns (uint32) {
        require(value <= type(uint32).max, "SafeCast: value doesn't fit in 32 bits");
        return uint32(value);
    }

    /**
     * @dev Returns the downcasted uint16 from uint256, reverting on
     * overflow (when the input is greater than largest uint16).
     *
     * Counterpart to Solidity's `uint16` operator.
     *
     * Requirements:
     *
     * - input must fit into 16 bits
     */
    function toUint16(uint256 value) internal pure returns (uint16) {
        require(value <= type(uint16).max, "SafeCast: value doesn't fit in 16 bits");
        return uint16(value);
    }

    /**
     * @dev Returns the downcasted uint8 from uint256, reverting on
     * overflow (when the input is greater than largest uint8).
     *
     * Counterpart to Solidity's `uint8` operator.
     *
     * Requirements:
     *
     * - input must fit into 8 bits.
     */
    function toUint8(uint256 value) internal pure returns (uint8) {
        require(value <= type(uint8).max, "SafeCast: value doesn't fit in 8 bits");
        return uint8(value);
    }

    /**
     * @dev Converts a signed int256 into an unsigned uint256.
     *
     * Requirements:
     *
     * - input must be greater than or equal to 0.
     */
    function toUint256(int256 value) internal pure returns (uint256) {
        require(value >= 0, "SafeCast: value must be positive");
        return uint256(value);
    }

    /**
     * @dev Returns the downcasted int128 from int256, reverting on
     * overflow (when the input is less than smallest int128 or
     * greater than largest int128).
     *
     * Counterpart to Solidity's `int128` operator.
     *
     * Requirements:
     *
     * - input must fit into 128 bits
     *
     * _Available since v3.1._
     */
    function toInt128(int256 value) internal pure returns (int128) {
        require(value >= type(int128).min && value <= type(int128).max, "SafeCast: value doesn't fit in 128 bits");
        return int128(value);
    }

    /**
     * @dev Returns the downcasted int64 from int256, reverting on
     * overflow (when the input is less than smallest int64 or
     * greater than largest int64).
     *
     * Counterpart to Solidity's `int64` operator.
     *
     * Requirements:
     *
     * - input must fit into 64 bits
     *
     * _Available since v3.1._
     */
    function toInt64(int256 value) internal pure returns (int64) {
        require(value >= type(int64).min && value <= type(int64).max, "SafeCast: value doesn't fit in 64 bits");
        return int64(value);
    }

    /**
     * @dev Returns the downcasted int32 from int256, reverting on
     * overflow (when the input is less than smallest int32 or
     * greater than largest int32).
     *
     * Counterpart to Solidity's `int32` operator.
     *
     * Requirements:
     *
     * - input must fit into 32 bits
     *
     * _Available since v3.1._
     */
    function toInt32(int256 value) internal pure returns (int32) {
        require(value >= type(int32).min && value <= type(int32).max, "SafeCast: value doesn't fit in 32 bits");
        return int32(value);
    }

    /**
     * @dev Returns the downcasted int16 from int256, reverting on
     * overflow (when the input is less than smallest int16 or
     * greater than largest int16).
     *
     * Counterpart to Solidity's `int16` operator.
     *
     * Requirements:
     *
     * - input must fit into 16 bits
     *
     * _Available since v3.1._
     */
    function toInt16(int256 value) internal pure returns (int16) {
        require(value >= type(int16).min && value <= type(int16).max, "SafeCast: value doesn't fit in 16 bits");
        return int16(value);
    }

    /**
     * @dev Returns the downcasted int8 from int256, reverting on
     * overflow (when the input is less than smallest int8 or
     * greater than largest int8).
     *
     * Counterpart to Solidity's `int8` operator.
     *
     * Requirements:
     *
     * - input must fit into 8 bits.
     *
     * _Available since v3.1._
     */
    function toInt8(int256 value) internal pure returns (int8) {
        require(value >= type(int8).min && value <= type(int8).max, "SafeCast: value doesn't fit in 8 bits");
        return int8(value);
    }

    /**
     * @dev Converts an unsigned uint256 into a signed int256.
     *
     * Requirements:
     *
     * - input must be less than or equal to maxInt256.
     */
    function toInt256(uint256 value) internal pure returns (int256) {
        // Note: Unsafe cast below is okay because `type(int256).max` is guaranteed to be positive
        require(value <= uint256(type(int256).max), "SafeCast: value doesn't fit in an int256");
        return int256(value);
    }
}

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (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`, checking first that contract recipients
     * are aware of the ERC721 protocol to prevent tokens from being forever locked.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId
    ) 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 Returns the account approved for `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function getApproved(uint256 tokenId) external view returns (address operator);

    /**
     * @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 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);

    /**
     * @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;
}

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (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 `IERC721.onERC721Received.selector`.
     */
    function onERC721Received(
        address operator,
        address from,
        uint256 tokenId,
        bytes calldata data
    ) external returns (bytes4);
}

// 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/Address.sol



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

                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/utils/Strings.sol



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

pragma solidity ^0.8.0;

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

    /**
     * @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);
    }
}

// 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);
}