ETH Price: $2,794.88 (+6.20%)

Transaction Decoder

Block:
22877045 at Jul-08-2025 09:05:59 PM +UTC
Transaction Fee:
0.00015305874 ETH $0.43
Gas Used:
124,438 Gas / 1.23 Gwei

Emitted Events:

298 DarkSuperBunnies.Approval( owner=[Receiver] 0xa753577be4d81952d7f302d60c9b0f09cfecc022, approved=0x00000000...000000000, tokenId=6398 )
299 DarkSuperBunnies.Transfer( from=[Receiver] 0xa753577be4d81952d7f302d60c9b0f09cfecc022, to=[Sender] 0xc1df99d6a67be1fbab258b9b334811ae672707a0, tokenId=6398 )
300 0xa753577be4d81952d7f302d60c9b0f09cfecc022.0x446928f7fd842bfa1ad8f7d2aadcfdda1bf5b4c1fef6fcec88d2484bc4478e48( 0x446928f7fd842bfa1ad8f7d2aadcfdda1bf5b4c1fef6fcec88d2484bc4478e48, 0x000000000000000000000000c1df99d6a67be1fbab258b9b334811ae672707a0, 0000000000000000000000000000000000000000000000000000000000000040, 00000000000000000000000000000000000000000000000000000000000001c0, 0000000000000000000000000000000000000000000000000000000000000001, 0000000000000000000000000000000000000000000000000000000000000020, 00000000000000000000000032895105b3a65da694c63a3f5f7347d5ebf07f07, 0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000000000000000060, 00000000000000000000000000000000000000000000000000000000000000a4, b88d4fde000000000000000000000000a753577be4d81952d7f302d60c9b0f09, cfecc022000000000000000000000000c1df99d6a67be1fbab258b9b334811ae, 672707a000000000000000000000000000000000000000000000000000000000, 000018fe00000000000000000000000000000000000000000000000000000000, 0000008000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000000000000000001, 0000000000000000000000000000000000000000000000000000000000000020, 0000000000000000000000000000000000000000000000000000000000000000 )

Account State Difference:

  Address   Before After State Difference Code
0x32895105...5eBf07F07
(Titan Builder)
58.771356804442107465 Eth58.771392670304049775 Eth0.00003586586194231
0xA753577B...9cFECC022 From: 22892027200963896143875287824492854295996611707088298155 To: 22892027718979953966499050587140250401159018568423161883
0xc1df99d6...E672707a0
0.031983524760925168 Eth
Nonce: 596
0.031830466020925168 Eth
Nonce: 597
0.00015305874

Execution Trace

0xa753577be4d81952d7f302d60c9b0f09cfecc022.34fcd5be( )
  • DarkSuperBunnies.safeTransferFrom( from=0xA753577Be4d81952D7F302D60c9b0f09cFECC022, to=0xc1df99d6A67bE1Fbab258B9B334811aE672707a0, tokenId=6398, _data=0x )
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.8.0 <0.9.0;
    import "@openzeppelin/contracts/utils/Counters.sol";
    import "./ERC721Tradable.sol";
    contract DarkSuperBunnies is ERC721Tradable {
        using SafeMath for uint256;
        using Address for address;
        using Strings for uint256;
        using Counters for Counters.Counter;
        Counters.Counter private _tokenIdCounter;
        Counters.Counter private _reservedTokenIdCounter;
        /**
         * 🐯
         */
        address public superTigerContract;
        uint256 public constant NFT_PRICE = 80000000000000000; // 0.08 ETH
        uint public constant MAX_NFT_PURCHASE = 100;
        uint256 public constant NFT_PRICE_PRE_SALE = 58000000000000000; // 0.058 ETH for pre-sale
        uint public constant MAX_NFT_PURCHASE_PRE_SALE = 10;
        uint256 public constant NFT_PRICE_LOVE = 69000000000000000; // 0.069 ETH for the best community
        uint public constant MAX_NFT_PURCHASE_LOVE = 100;
        uint256 public MAX_SUPPLY = 10000;
        /**
         * Reserve tokens for the team and community giveaways
         */
        uint public constant RESERVED_TOTAL = 325;
        bool public isSaleActive = false;
        bool public isPreSaleActive = false;
        bool public isRevealed = false;
        string public provenanceHash;
        string private _baseURIExtended;
        string private _placeholderURIExtended;
        constructor(
            address _proxyRegistryAddress
        ) ERC721Tradable('DarkSuperBunnies', 'DSB', _proxyRegistryAddress) {
            /**
             * Start counting tokens with a reserved shift
             */
            _tokenIdCounter._value = 5000;
        }
        /**
         * @dev Withdraw ether from the contract
        */
        function withdraw() onlyOwner public {
            uint balance = address(this).balance;
            payable(msg.sender).transfer(balance);
        }
        function _baseURI() internal view virtual override returns (string memory) {
            return _baseURIExtended;
        }
        function setBaseURI(string memory baseURI_) external onlyOwner {
            _baseURIExtended = baseURI_;
        }
        function setPlaceholderURI(string memory placeholderURI_) external onlyOwner {
            _placeholderURIExtended = placeholderURI_;
        }
        function setProvenanceHash(string memory provenanceHash_) external onlyOwner {
            provenanceHash = provenanceHash_;
        }
        function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
            require(_exists(tokenId), "ERC721Metadata: URI query for nonexistent token");
            if (!isRevealed) {
                return _placeholderURIExtended;
            }
            string memory base = _baseURI();
            return string(abi.encodePacked(base, tokenId.toString()));
        }
        function setSuperTigerContractAddress(address contractAddress) public onlyOwner {
            superTigerContract = contractAddress;
        }
        function flipSaleState() public onlyOwner {
            isSaleActive = !isSaleActive;
        }
        function flipPreSaleState() public onlyOwner {
            isPreSaleActive = !isPreSaleActive;
        }
        function flipAllSaleStates() external onlyOwner {
           flipSaleState();
           flipPreSaleState();
        }
        function flipReveal() external onlyOwner {
            isRevealed = !isRevealed;
        }
        function _mintGeneric(
            uint256 CURRENT_NFT_PRICE,
            uint CURRENT_TOKENS_NUMBER_LIMIT,
            uint numberOfTokens
        ) internal {
            require(isSaleActive, "Sale is not active at the moment");
            require(numberOfTokens > 0, "Number of tokens can not be less than or equal to 0");
            require(_tokenIdCounter.current().add(numberOfTokens) <= MAX_SUPPLY, "Purchase would exceed max supply");
            if (isPreSaleActive) {
                CURRENT_NFT_PRICE = NFT_PRICE_PRE_SALE;
                CURRENT_TOKENS_NUMBER_LIMIT = MAX_NFT_PURCHASE_PRE_SALE;
            }
            require(numberOfTokens <= CURRENT_TOKENS_NUMBER_LIMIT, "Tokens amount is out of limit");
            require(CURRENT_NFT_PRICE.mul(numberOfTokens) == msg.value, "Sent ether value is incorrect");
            for (uint i = 0; i < numberOfTokens; i++) {
                _safeMintGeneric(msg.sender, _tokenIdCounter);
            }
        }
        function mint(uint numberOfTokens) public payable {
            _mintGeneric(NFT_PRICE, MAX_NFT_PURCHASE, numberOfTokens);
        }
        function mintLove(uint numberOfTokens) public payable {
            _mintGeneric(NFT_PRICE_LOVE, MAX_NFT_PURCHASE_LOVE, numberOfTokens);
        }
        /**
         * Lazily mint some reserved tokens
         */
        function mintReserved(uint numberOfTokens) public onlyOwner {
            require(
                _reservedTokenIdCounter.current().add(numberOfTokens) <= RESERVED_TOTAL,
                "Minting would exceed max reserved supply"
            );
           for (uint i = 0; i < numberOfTokens; i++) {
                _safeMintGeneric(msg.sender, _reservedTokenIdCounter);
            }
        }
        function levelUp(uint256 useTokenId1, uint256 useTokenId2, uint256 useTokenId3) public {
            require(superTigerContract != address(0), "SuperTiger contract address need be set");
            address from = msg.sender;
            require(ERC721.ownerOf(useTokenId1) == from, "ERC721: use of token1 that is not own");
            require(ERC721.ownerOf(useTokenId2) == from, "ERC721: use of token2 that is not own");
            require(ERC721.ownerOf(useTokenId3) == from, "ERC721: use of token3 that is not own");
            burn(useTokenId1);
            burn(useTokenId2);
            burn(useTokenId3);
            SuperTiger superTiger = SuperTiger(superTigerContract);
            bool result = superTiger.composeSuperTiger(from);
            require(result, "SuperTiger compose failed");
        }
    }
    interface SuperTiger {
        function composeSuperTiger(address owner) external returns (bool);
    }
    // SPDX-License-Identifier: MIT
    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;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.8.0 <0.9.0;
    import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
    import "@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol";
    import "@openzeppelin/contracts/token/ERC721/extensions/ERC721URIStorage.sol";
    import "@openzeppelin/contracts/token/ERC721/extensions/ERC721Burnable.sol";
    import "@openzeppelin/contracts/access/Ownable.sol";
    import "@openzeppelin/contracts/utils/Counters.sol";
    import "./common/meta-transactions/ContentMixin.sol";
    import "./common/meta-transactions/NativeMetaTransaction.sol";
    contract OwnableDelegateProxy {}
    contract ProxyRegistry {
        mapping(address => OwnableDelegateProxy) public proxies;
    }
    /**
     * @title ERC721Tradable
     * ERC721Tradable - ERC721 contract that whitelists a trading address, and has minting functionality.
     */
    abstract contract ERC721Tradable is
        ContextMixin,
        ERC721Enumerable,
        NativeMetaTransaction,
        ERC721URIStorage,
        ERC721Burnable,
        Ownable
    {
        using Counters for Counters.Counter;
        // Counters.Counter private _tokenIdCounter;
        // Counters.Counter private _reservedTokenIdCounter;
        address proxyRegistryAddress;
        event PermanentURI(string value, uint256 indexed id);
        constructor(
            string memory _name,
            string memory _symbol,
            address _proxyRegistryAddress
        ) ERC721(_name, _symbol) {
            proxyRegistryAddress = _proxyRegistryAddress;
            _initializeEIP712(_name);
        }
        function _safeMintGeneric(address to, Counters.Counter storage counter) internal {
            uint256 newTokenId = counter.current();
            _safeMint(to, newTokenId);
            counter.increment();
        }
        function _setPermanentURI(uint256 id, string memory uri)
            internal
        {
            _setTokenURI(id, uri);
            emit PermanentURI(uri, id);
        }
        function _beforeTokenTransfer(address from, address to, uint256 tokenId)
            internal
            override(ERC721, ERC721Enumerable)
        {
            super._beforeTokenTransfer(from, to, tokenId);
        }
        function _burn(uint256 tokenId)
            internal
            override(ERC721, ERC721URIStorage)
        {
            super._burn(tokenId);
        }
        function tokenURI(uint256 tokenId)
            public
            virtual
            view
            override(ERC721, ERC721URIStorage)
            returns (string memory)
        {
            return super.tokenURI(tokenId);
        }
        function supportsInterface(bytes4 interfaceId)
            public
            view
            override(ERC721, ERC721Enumerable)
            returns (bool)
        {
            return super.supportsInterface(interfaceId);
        }
        /**
         * Override isApprovedForAll to whitelist user's OpenSea proxy accounts to enable gas-less listings.
         */
        function isApprovedForAll(address owner, address operator)
            public
            view
            override
            returns (bool)
        {
            // Whitelist OpenSea proxy contract for easy trading.
            ProxyRegistry proxyRegistry = ProxyRegistry(proxyRegistryAddress);
            if (address(proxyRegistry.proxies(owner)) == operator) {
                return true;
            }
            return super.isApprovedForAll(owner, operator);
        }
        /**
         * This is used instead of msg.sender as transactions won't be sent by the original token owner, but by OpenSea.
         */
        function _msgSender()
            internal
            view
            override
            returns (address sender)
        {
            return ContextMixin.msgSender();
        }
    }
    // SPDX-License-Identifier: MIT
    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 {
            require(operator != _msgSender(), "ERC721: approve to caller");
            _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 {
            //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);
        }
        /**
         * @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);
        }
        /**
         * @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 of token that is not own");
            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);
        }
        /**
         * @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 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 {}
    }
    // SPDX-License-Identifier: MIT
    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();
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "../ERC721.sol";
    /**
     * @dev ERC721 token with storage based token URI management.
     */
    abstract contract ERC721URIStorage is ERC721 {
        using Strings for uint256;
        // Optional mapping for token URIs
        mapping(uint256 => string) private _tokenURIs;
        /**
         * @dev See {IERC721Metadata-tokenURI}.
         */
        function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
            require(_exists(tokenId), "ERC721URIStorage: URI query for nonexistent token");
            string memory _tokenURI = _tokenURIs[tokenId];
            string memory base = _baseURI();
            // If there is no base URI, return the token URI.
            if (bytes(base).length == 0) {
                return _tokenURI;
            }
            // If both are set, concatenate the baseURI and tokenURI (via abi.encodePacked).
            if (bytes(_tokenURI).length > 0) {
                return string(abi.encodePacked(base, _tokenURI));
            }
            return super.tokenURI(tokenId);
        }
        /**
         * @dev Sets `_tokenURI` as the tokenURI of `tokenId`.
         *
         * Requirements:
         *
         * - `tokenId` must exist.
         */
        function _setTokenURI(uint256 tokenId, string memory _tokenURI) internal virtual {
            require(_exists(tokenId), "ERC721URIStorage: URI set of nonexistent token");
            _tokenURIs[tokenId] = _tokenURI;
        }
        /**
         * @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 override {
            super._burn(tokenId);
            if (bytes(_tokenURIs[tokenId]).length != 0) {
                delete _tokenURIs[tokenId];
            }
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "../ERC721.sol";
    import "../../../utils/Context.sol";
    /**
     * @title ERC721 Burnable Token
     * @dev ERC721 Token that can be irreversibly burned (destroyed).
     */
    abstract contract ERC721Burnable is Context, ERC721 {
        /**
         * @dev Burns `tokenId`. See {ERC721-_burn}.
         *
         * Requirements:
         *
         * - The caller must own `tokenId` or be an approved operator.
         */
        function burn(uint256 tokenId) public virtual {
            //solhint-disable-next-line max-line-length
            require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721Burnable: caller is not owner nor approved");
            _burn(tokenId);
        }
    }
    // SPDX-License-Identifier: MIT
    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() {
            _setOwner(_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 {
            _setOwner(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");
            _setOwner(newOwner);
        }
        function _setOwner(address newOwner) private {
            address oldOwner = _owner;
            _owner = newOwner;
            emit OwnershipTransferred(oldOwner, newOwner);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.8.0 <0.9.0;
    abstract contract ContextMixin {
        function msgSender()
            internal
            view
            returns (address payable sender)
        {
            if (msg.sender == address(this)) {
                bytes memory array = msg.data;
                uint256 index = msg.data.length;
                assembly {
                    // Load the 32 bytes word from memory with the address on the lower 20 bytes, and mask those.
                    sender := and(
                        mload(add(array, index)),
                        0xffffffffffffffffffffffffffffffffffffffff
                    )
                }
            } else {
                sender = payable(msg.sender);
            }
            return sender;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.8.0 <0.9.0;
    import {EIP712Base} from "./EIP712Base.sol";
    import "@openzeppelin/contracts/utils/math/SafeMath.sol";
    contract NativeMetaTransaction is EIP712Base {
        using SafeMath for uint256;
        bytes32 private constant META_TRANSACTION_TYPEHASH = keccak256(
            bytes(
                "MetaTransaction(uint256 nonce,address from,bytes functionSignature)"
            )
        );
        event MetaTransactionExecuted(
            address userAddress,
            address payable relayerAddress,
            bytes functionSignature
        );
        mapping(address => uint256) nonces;
        /*
         * Meta transaction structure.
         * No point of including value field here as if user is doing value transfer then he has the funds to pay for gas
         * He should call the desired function directly in that case.
         */
        struct MetaTransaction {
            uint256 nonce;
            address from;
            bytes functionSignature;
        }
        function executeMetaTransaction(
            address userAddress,
            bytes memory functionSignature,
            bytes32 sigR,
            bytes32 sigS,
            uint8 sigV
        ) public payable returns (bytes memory) {
            MetaTransaction memory metaTx = MetaTransaction({
                nonce: nonces[userAddress],
                from: userAddress,
                functionSignature: functionSignature
            });
            require(
                verify(userAddress, metaTx, sigR, sigS, sigV),
                "Signer and signature do not match"
            );
            // increase nonce for user (to avoid re-use)
            nonces[userAddress] = nonces[userAddress].add(1);
            emit MetaTransactionExecuted(
                userAddress,
                payable(msg.sender),
                functionSignature
            );
            // Append userAddress and relayer address at the end to extract it from calling context
            (bool success, bytes memory returnData) = address(this).call(
                abi.encodePacked(functionSignature, userAddress)
            );
            require(success, "Function call not successful");
            return returnData;
        }
        function hashMetaTransaction(MetaTransaction memory metaTx)
            internal
            pure
            returns (bytes32)
        {
            return
                keccak256(
                    abi.encode(
                        META_TRANSACTION_TYPEHASH,
                        metaTx.nonce,
                        metaTx.from,
                        keccak256(metaTx.functionSignature)
                    )
                );
        }
        function getNonce(address user) public view returns (uint256 nonce) {
            nonce = nonces[user];
        }
        function verify(
            address signer,
            MetaTransaction memory metaTx,
            bytes32 sigR,
            bytes32 sigS,
            uint8 sigV
        ) internal view returns (bool) {
            require(signer != address(0), "NativeMetaTransaction: INVALID_SIGNER");
            return
                signer ==
                ecrecover(
                    toTypedMessageHash(hashMetaTransaction(metaTx)),
                    sigV,
                    sigR,
                    sigS
                );
        }
    }
    // SPDX-License-Identifier: MIT
    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;
    }
    // SPDX-License-Identifier: MIT
    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);
    }
    // SPDX-License-Identifier: MIT
    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);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @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
         * ====
         */
        function isContract(address account) internal view returns (bool) {
            // This method relies on extcodesize, which returns 0 for contracts in
            // construction, since the code is only stored at the end of the
            // constructor execution.
            uint256 size;
            assembly {
                size := extcodesize(account)
            }
            return size > 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);
                }
            }
        }
    }
    // SPDX-License-Identifier: MIT
    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;
        }
    }
    // SPDX-License-Identifier: MIT
    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);
        }
    }
    // SPDX-License-Identifier: MIT
    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;
        }
    }
    // SPDX-License-Identifier: MIT
    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);
    }
    // SPDX-License-Identifier: MIT
    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 tokenId);
        /**
         * @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);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.8.0 <0.9.0;
    import {Initializable} from "./Initializable.sol";
    contract EIP712Base is Initializable {
        struct EIP712Domain {
            string name;
            string version;
            address verifyingContract;
            bytes32 salt;
        }
        string constant public ERC712_VERSION = "1";
        bytes32 internal constant EIP712_DOMAIN_TYPEHASH = keccak256(
            bytes(
                "EIP712Domain(string name,string version,address verifyingContract,bytes32 salt)"
            )
        );
        bytes32 internal domainSeperator;
        // supposed to be called once while initializing.
        // one of the contracts that inherits this contract follows proxy pattern
        // so it is not possible to do this in a constructor
        function _initializeEIP712(
            string memory name
        )
            internal
            initializer
        {
            _setDomainSeperator(name);
        }
        function _setDomainSeperator(string memory name) internal {
            domainSeperator = keccak256(
                abi.encode(
                    EIP712_DOMAIN_TYPEHASH,
                    keccak256(bytes(name)),
                    keccak256(bytes(ERC712_VERSION)),
                    address(this),
                    bytes32(getChainId())
                )
            );
        }
        function getDomainSeperator() public view returns (bytes32) {
            return domainSeperator;
        }
        function getChainId() public view returns (uint256) {
            uint256 id;
            assembly {
                id := chainid()
            }
            return id;
        }
        /**
         * Accept message hash and returns hash message in EIP712 compatible form
         * So that it can be used to recover signer from signature signed using EIP712 formatted data
         * https://eips.ethereum.org/EIPS/eip-712
         * "\\\\x19" makes the encoding deterministic
         * "\\\\x01" is the version byte to make it compatible to EIP-191
         */
        function toTypedMessageHash(bytes32 messageHash)
            internal
            view
            returns (bytes32)
        {
            return
                keccak256(
                    abi.encodePacked("\\x19\\x01", getDomainSeperator(), messageHash)
                );
        }
    }// SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    // CAUTION
    // This version of SafeMath should only be used with Solidity 0.8 or later,
    // because it relies on the compiler's built in overflow checks.
    /**
     * @dev Wrappers over Solidity's arithmetic operations.
     *
     * NOTE: `SafeMath` is no longer needed starting with Solidity 0.8. The compiler
     * now has built in overflow checking.
     */
    library SafeMath {
        /**
         * @dev Returns the addition of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            unchecked {
                uint256 c = a + b;
                if (c < a) return (false, 0);
                return (true, c);
            }
        }
        /**
         * @dev Returns the substraction of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            unchecked {
                if (b > a) return (false, 0);
                return (true, a - b);
            }
        }
        /**
         * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            unchecked {
                // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
                // benefit is lost if 'b' is also tested.
                // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
                if (a == 0) return (true, 0);
                uint256 c = a * b;
                if (c / a != b) return (false, 0);
                return (true, c);
            }
        }
        /**
         * @dev Returns the division of two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            unchecked {
                if (b == 0) return (false, 0);
                return (true, a / b);
            }
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            unchecked {
                if (b == 0) return (false, 0);
                return (true, a % b);
            }
        }
        /**
         * @dev Returns the addition of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `+` operator.
         *
         * Requirements:
         *
         * - Addition cannot overflow.
         */
        function add(uint256 a, uint256 b) internal pure returns (uint256) {
            return a + b;
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting on
         * overflow (when the result is negative).
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(uint256 a, uint256 b) internal pure returns (uint256) {
            return a - b;
        }
        /**
         * @dev Returns the multiplication of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `*` operator.
         *
         * Requirements:
         *
         * - Multiplication cannot overflow.
         */
        function mul(uint256 a, uint256 b) internal pure returns (uint256) {
            return a * b;
        }
        /**
         * @dev Returns the integer division of two unsigned integers, reverting on
         * division by zero. The result is rounded towards zero.
         *
         * Counterpart to Solidity's `/` operator.
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(uint256 a, uint256 b) internal pure returns (uint256) {
            return a / b;
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting when dividing by zero.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(uint256 a, uint256 b) internal pure returns (uint256) {
            return a % b;
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
         * overflow (when the result is negative).
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {trySub}.
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(
            uint256 a,
            uint256 b,
            string memory errorMessage
        ) internal pure returns (uint256) {
            unchecked {
                require(b <= a, errorMessage);
                return a - b;
            }
        }
        /**
         * @dev Returns the integer division of two unsigned integers, reverting with custom message on
         * division by zero. The result is rounded towards zero.
         *
         * Counterpart to Solidity's `/` operator. Note: this function uses a
         * `revert` opcode (which leaves remaining gas untouched) while Solidity
         * uses an invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(
            uint256 a,
            uint256 b,
            string memory errorMessage
        ) internal pure returns (uint256) {
            unchecked {
                require(b > 0, errorMessage);
                return a / b;
            }
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting with custom message when dividing by zero.
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {tryMod}.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(
            uint256 a,
            uint256 b,
            string memory errorMessage
        ) internal pure returns (uint256) {
            unchecked {
                require(b > 0, errorMessage);
                return a % b;
            }
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.8.0 <0.9.0;
    contract Initializable {
        bool inited = false;
        modifier initializer() {
            require(!inited, "already inited");
            _;
            inited = true;
        }
    }