ETH Price: $2,332.46 (+1.89%)

Transaction Decoder

Block:
14115599 at Jan-31-2022 07:40:09 PM +UTC
Transaction Fee:
0.015016711892999351 ETH $35.03
Gas Used:
119,813 Gas / 125.334578827 Gwei

Emitted Events:

Account State Difference:

  Address   Before After State Difference Code
(Flexpool.io)
5,839.591036161344697162 Eth5,839.591215880844697162 Eth0.0001797195
0xAf615B61...e77b6CCa8 183.2 Eth183.4 Eth0.2
0xcb4d5E70...1295399f1
0.289566233118356028 Eth
Nonce: 172
0.074549521225356677 Eth
Nonce: 173
0.215016711892999351

Execution Trace

ETH 0.2 LivesOfAsuna.registerAndMintForWhitelist( hash=17A78DF063AE2E083BCC8F8B7797AF943E51C21281654C46ED74D3F872CDB160, signature=0xF7A827B4B237C2383BA8CF8E5AE761F2F58CBC9A41E2DCF974AD3B523AE832583F4E00B9639EDDF0071AF02470F5B6D087FFC2A7D363F87ABF4AA3C3714CDB5E1C, numberOfTokens=1, customLimit=1 )
  • Null: 0x000...001.17a78df0( )
    // Author: Eric Gao (@itsoksami, https://github.com/Ericxgao)
    pragma solidity 0.8.10;
    import "./BaseFixedPriceAuctionERC721A.sol";
    contract LivesOfAsuna is BaseFixedPriceAuctionERC721A {
        mapping(uint256 => bool) private _usedNonces;
        mapping(uint256 => string) private _tokenURIs;
        mapping(address => uint256) private _variableWhitelistAmounts;
        string public tokenURIPrefix = "Lives of Asuna Token URI Verification:";
        string public mintWhitelistWithAmountPrefix = "Lives of Asuna Whitelist Verification:";
        constructor(
            address[] memory payees, 
            uint256[] memory shares,
            string memory name,
            string memory symbol,
            uint256 _whitelistMaxMint, 
            uint256 _publicListMaxMint,
            uint256 _nonReservedMax,
            uint256 _reservedMax,
            uint256 _price
        )
            BaseFixedPriceAuctionERC721A(payees, shares, name, symbol, _whitelistMaxMint, _publicListMaxMint, _nonReservedMax, _reservedMax, _price)
        {
        }
        function _hashSetTokenURI(string memory _prefix, address _address, string memory _tokenURI, uint256 _nonce) internal view returns (bytes32) {
            return keccak256(abi.encodePacked(_prefix, _address, _tokenURI, _nonce));
        }
        function _hashRegisterForWhitelistWithAmount(string memory _prefix, address _address, uint256 amount) internal view returns (bytes32) {
            return keccak256(abi.encodePacked(_prefix, _address, amount));
        }
        function setTokenURI(uint256 tokenId, string memory _tokenURI, uint256 nonce, bytes32 hash, bytes calldata signature) 
            external
        {       
            require(_verify(hash, signature), "Signature invalid.");
            require(_hashSetTokenURI(tokenURIPrefix, msg.sender, _tokenURI, nonce) == hash, "Hash invalid.");
            require(!_usedNonces[nonce], "Nonce already used.");
            require(ownerOf(tokenId) == msg.sender, "You do not own this token.");
            _usedNonces[nonce] = true;
            _tokenURIs[tokenId] = _tokenURI;
        }
        function tokenURI(uint256 tokenId) public view override returns (string memory) {
            require(_exists(tokenId), 'Token does not exist');
            string memory directTokenURI = _tokenURIs[tokenId];
            if (bytes(directTokenURI).length > 0) {
                return directTokenURI;
            }
            return super.tokenURI(tokenId);
        }
        function registerAndMintForWhitelist(bytes32 hash, bytes calldata signature, uint256 numberOfTokens, uint256 customLimit) external payable {
            require(_verify(hash, signature), "Signature invalid.");
            require(_hashRegisterForWhitelistWithAmount(mintWhitelistWithAmountPrefix, msg.sender, customLimit) == hash, "Hash invalid.");
            require(_whitelistClaimed[msg.sender] + numberOfTokens <= customLimit, 'You cannot mint this many.');
            require(_whitelistClaimed[msg.sender] + numberOfTokens <= whitelistMaxMint, 'You cannot mint this many.');
            _whitelistClaimed[msg.sender] += numberOfTokens;
            _nonReservedMintHelper(numberOfTokens);
        }
    }// Author: Eric Gao (@itsoksami, https://github.com/Ericxgao)
    // Author: Azuki (ERC721A, https://github.com/chiru-labs/ERC721A)
    pragma solidity 0.8.10;
    import "erc721a/contracts/ERC721A.sol";
    import "@openzeppelin/contracts/utils/Strings.sol";
    import "@openzeppelin/contracts/utils/cryptography/ECDSA.sol";
    import "@openzeppelin/contracts/finance/PaymentSplitter.sol";
    import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
    import "@openzeppelin/contracts/access/Ownable.sol";
    contract BaseFixedPriceAuctionERC721A is ERC721A, ReentrancyGuard, Ownable {
        using Strings for uint256;
        using ECDSA for bytes32;
        string public prefix = "Base Verification:";
        string private baseTokenURI = '';
        mapping(address => uint256) public _whitelistClaimed;
        mapping(address => uint256) public _publicListClaimed;
        uint256 public nonReservedMax;
        uint256 public reservedMax;
        uint256 public max;
        uint256 public nonReservedMinted;
        uint256 public reservedMinted;
        uint256 public price;
        uint256 public whitelistMaxMint;
        uint256 public publicListMaxMint;
        PaymentSplitter private _splitter;
        constructor(
            address[] memory payees, 
            uint256[] memory shares,
            string memory name,
            string memory symbol,
            uint256 _whitelistMaxMint, 
            uint256 _publicListMaxMint,
            uint256 _nonReservedMax,
            uint256 _reservedMax,
            uint256 _price
        )
            ERC721A(name, symbol, 4)
        {
            whitelistMaxMint = _whitelistMaxMint;
            publicListMaxMint = _publicListMaxMint;
            nonReservedMax = _nonReservedMax;
            reservedMax = _reservedMax;
            max = nonReservedMax + reservedMax;
            nonReservedMinted = 0;
            reservedMinted = 0;
            _splitter = new PaymentSplitter(payees, shares);
            price = _price;
        }
        function setPrice(uint256 _price) public onlyOwner {
            price = _price;
        }
        function release(address payable account) external {
            _splitter.release(account);
        }
        function _hash(address _address) internal view returns (bytes32) {
            return keccak256(abi.encodePacked(prefix, _address));
        }
        function _verify(bytes32 hash, bytes memory signature) internal view returns (bool) {
            return (_recover(hash, signature) == owner());
        }
        function _recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
            return hash.recover(signature);
        }
        function setPrefix(string memory _prefix) public onlyOwner {
            prefix = _prefix;
        }
        function setWhitelistMaxMint(uint256 _whitelistMaxMint) external onlyOwner {
            whitelistMaxMint = _whitelistMaxMint;
        }
        function setPublicListMaxMint(uint256 _publicListMaxMint) external onlyOwner {
            publicListMaxMint = _publicListMaxMint;
        }
        function mintPublic(uint256 numberOfTokens) external payable {
            require(_publicListClaimed[msg.sender] + numberOfTokens <= publicListMaxMint, 'You cannot mint this many.');
            _nonReservedMintHelper(numberOfTokens);
            _publicListClaimed[msg.sender] += numberOfTokens;
        }
        
        function mintWhitelist(bytes32 hash, bytes calldata signature, uint256 numberOfTokens) external payable {
            require(_verify(hash, signature), "This hash's signature is invalid.");
            require(_hash(msg.sender) == hash, "The address hash does not match the signed hash.");
            require(_whitelistClaimed[msg.sender] + numberOfTokens <= whitelistMaxMint, 'You cannot mint this many.');
            _nonReservedMintHelper(numberOfTokens);
            _whitelistClaimed[msg.sender] += numberOfTokens;
        }
        function _nonReservedMintHelper(uint256 numberOfTokens) internal {
            require(numberOfTokens * price == msg.value, "Invalid amount.");
            require(totalSupply() + numberOfTokens <= max, "Sold out.");
            _safeMint(msg.sender, numberOfTokens);
        }
        function splitPayments() public payable onlyOwner {
            (bool success, ) = payable(_splitter).call{value: address(this).balance}(
            ""
            );
            require(success);
        }
        function mintReserved(uint256 quantity) external onlyOwner {
            require(
                totalSupply() + quantity <= reservedMax,
                "Sold out."
            );
            if (quantity < maxBatchSize) {
                _safeMint(msg.sender, quantity);
            } else {
                require(
                    quantity % maxBatchSize == 0,
                    "Can only mint a multiple of the maxBatchSize."
                );
                uint256 numChunks = quantity / maxBatchSize;
                for (uint256 i = 0; i < numChunks; i++) {
                    _safeMint(msg.sender, maxBatchSize);
                }
            }
        }
        function setBaseURI(string memory baseTokenURI_) external onlyOwner {
            baseTokenURI = baseTokenURI_;
        }
        function tokenURI(uint256 tokenId)
            public
            view
            virtual
            override
            returns (string memory)
        {
            return string(abi.encodePacked(baseTokenURI, tokenId.toString()));
        }
    }// SPDX-License-Identifier: MIT
    // Creator: Chiru Labs
    pragma solidity ^0.8.0;
    import "@openzeppelin/contracts/token/ERC721/IERC721.sol";
    import "@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol";
    import "@openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol";
    import "@openzeppelin/contracts/token/ERC721/extensions/IERC721Enumerable.sol";
    import "@openzeppelin/contracts/utils/Address.sol";
    import "@openzeppelin/contracts/utils/Context.sol";
    import "@openzeppelin/contracts/utils/Strings.sol";
    import "@openzeppelin/contracts/utils/introspection/ERC165.sol";
    /**
     * @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
     * the Metadata and Enumerable extension. Built to optimize for lower gas during batch mints.
     *
     * Assumes serials are sequentially minted starting at 0 (e.g. 0, 1, 2, 3..).
     *
     * Does not support burning tokens to address(0).
     */
    contract ERC721A is Context, ERC165, IERC721, IERC721Metadata, IERC721Enumerable {
        using Address for address;
        using Strings for uint256;
        struct TokenOwnership {
            address addr;
            uint64 startTimestamp;
        }
        struct AddressData {
            uint128 balance;
            uint128 numberMinted;
        }
        uint256 private currentIndex = 0;
        uint256 internal immutable maxBatchSize;
        // Token name
        string private _name;
        // Token symbol
        string private _symbol;
        // Mapping from token ID to ownership details
        // An empty struct value does not necessarily mean the token is unowned. See ownershipOf implementation for details.
        mapping(uint256 => TokenOwnership) private _ownerships;
        // Mapping owner address to address data
        mapping(address => AddressData) private _addressData;
        // Mapping from token ID to approved address
        mapping(uint256 => address) private _tokenApprovals;
        // Mapping from owner to operator approvals
        mapping(address => mapping(address => bool)) private _operatorApprovals;
        /**
         * @dev
         * `maxBatchSize` refers to how much a minter can mint at a time.
         */
        constructor(
            string memory name_,
            string memory symbol_,
            uint256 maxBatchSize_
        ) {
            require(maxBatchSize_ > 0, "ERC721A: max batch size must be nonzero");
            _name = name_;
            _symbol = symbol_;
            maxBatchSize = maxBatchSize_;
        }
        /**
         * @dev See {IERC721Enumerable-totalSupply}.
         */
        function totalSupply() public view override returns (uint256) {
            return currentIndex;
        }
        /**
         * @dev See {IERC721Enumerable-tokenByIndex}.
         */
        function tokenByIndex(uint256 index) public view override returns (uint256) {
            require(index < totalSupply(), "ERC721A: global index out of bounds");
            return index;
        }
        /**
         * @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.
         * This read function is O(totalSupply). If calling from a separate contract, be sure to test gas first.
         * It may also degrade with extremely large collection sizes (e.g >> 10000), test for your use case.
         */
        function tokenOfOwnerByIndex(address owner, uint256 index) public view override returns (uint256) {
            require(index < balanceOf(owner), "ERC721A: owner index out of bounds");
            uint256 numMintedSoFar = totalSupply();
            uint256 tokenIdsIdx = 0;
            address currOwnershipAddr = address(0);
            for (uint256 i = 0; i < numMintedSoFar; i++) {
                TokenOwnership memory ownership = _ownerships[i];
                if (ownership.addr != address(0)) {
                    currOwnershipAddr = ownership.addr;
                }
                if (currOwnershipAddr == owner) {
                    if (tokenIdsIdx == index) {
                        return i;
                    }
                    tokenIdsIdx++;
                }
            }
            revert("ERC721A: unable to get token of owner by index");
        }
        /**
         * @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 ||
                interfaceId == type(IERC721Enumerable).interfaceId ||
                super.supportsInterface(interfaceId);
        }
        /**
         * @dev See {IERC721-balanceOf}.
         */
        function balanceOf(address owner) public view override returns (uint256) {
            require(owner != address(0), "ERC721A: balance query for the zero address");
            return uint256(_addressData[owner].balance);
        }
        function _numberMinted(address owner) internal view returns (uint256) {
            require(owner != address(0), "ERC721A: number minted query for the zero address");
            return uint256(_addressData[owner].numberMinted);
        }
        function ownershipOf(uint256 tokenId) internal view returns (TokenOwnership memory) {
            require(_exists(tokenId), "ERC721A: owner query for nonexistent token");
            uint256 lowestTokenToCheck;
            if (tokenId >= maxBatchSize) {
                lowestTokenToCheck = tokenId - maxBatchSize + 1;
            }
            for (uint256 curr = tokenId; curr >= lowestTokenToCheck; curr--) {
                TokenOwnership memory ownership = _ownerships[curr];
                if (ownership.addr != address(0)) {
                    return ownership;
                }
            }
            revert("ERC721A: unable to determine the owner of token");
        }
        /**
         * @dev See {IERC721-ownerOf}.
         */
        function ownerOf(uint256 tokenId) public view override returns (address) {
            return ownershipOf(tokenId).addr;
        }
        /**
         * @dev See {IERC721Metadata-name}.
         */
        function name() public view virtual override returns (string memory) {
            return _name;
        }
        /**
         * @dev See {IERC721Metadata-symbol}.
         */
        function symbol() public view virtual override returns (string memory) {
            return _symbol;
        }
        /**
         * @dev See {IERC721Metadata-tokenURI}.
         */
        function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
            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 override {
            address owner = ERC721A.ownerOf(tokenId);
            require(to != owner, "ERC721A: approval to current owner");
            require(
                _msgSender() == owner || isApprovedForAll(owner, _msgSender()),
                "ERC721A: approve caller is not owner nor approved for all"
            );
            _approve(to, tokenId, owner);
        }
        /**
         * @dev See {IERC721-getApproved}.
         */
        function getApproved(uint256 tokenId) public view override returns (address) {
            require(_exists(tokenId), "ERC721A: approved query for nonexistent token");
            return _tokenApprovals[tokenId];
        }
        /**
         * @dev See {IERC721-setApprovalForAll}.
         */
        function setApprovalForAll(address operator, bool approved) public override {
            require(operator != _msgSender(), "ERC721A: 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 override {
            _transfer(from, to, tokenId);
        }
        /**
         * @dev See {IERC721-safeTransferFrom}.
         */
        function safeTransferFrom(
            address from,
            address to,
            uint256 tokenId
        ) public override {
            safeTransferFrom(from, to, tokenId, "");
        }
        /**
         * @dev See {IERC721-safeTransferFrom}.
         */
        function safeTransferFrom(
            address from,
            address to,
            uint256 tokenId,
            bytes memory _data
        ) public override {
            _transfer(from, to, tokenId);
            require(
                _checkOnERC721Received(from, to, tokenId, _data),
                "ERC721A: 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`),
         */
        function _exists(uint256 tokenId) internal view returns (bool) {
            return tokenId < currentIndex;
        }
        function _safeMint(address to, uint256 quantity) internal {
            _safeMint(to, quantity, "");
        }
        /**
         * @dev Mints `quantity` tokens and transfers them to `to`.
         *
         * Requirements:
         *
         * - `to` cannot be the zero address.
         * - `quantity` cannot be larger than the max batch size.
         *
         * Emits a {Transfer} event.
         */
        function _safeMint(
            address to,
            uint256 quantity,
            bytes memory _data
        ) internal {
            uint256 startTokenId = currentIndex;
            require(to != address(0), "ERC721A: mint to the zero address");
            // We know if the first token in the batch doesn't exist, the other ones don't as well, because of serial ordering.
            require(!_exists(startTokenId), "ERC721A: token already minted");
            require(quantity <= maxBatchSize, "ERC721A: quantity to mint too high");
            _beforeTokenTransfers(address(0), to, startTokenId, quantity);
            AddressData memory addressData = _addressData[to];
            _addressData[to] = AddressData(
                addressData.balance + uint128(quantity),
                addressData.numberMinted + uint128(quantity)
            );
            _ownerships[startTokenId] = TokenOwnership(to, uint64(block.timestamp));
            uint256 updatedIndex = startTokenId;
            for (uint256 i = 0; i < quantity; i++) {
                emit Transfer(address(0), to, updatedIndex);
                require(
                    _checkOnERC721Received(address(0), to, updatedIndex, _data),
                    "ERC721A: transfer to non ERC721Receiver implementer"
                );
                updatedIndex++;
            }
            currentIndex = updatedIndex;
            _afterTokenTransfers(address(0), to, startTokenId, quantity);
        }
        /**
         * @dev Transfers `tokenId` from `from` to `to`.
         *
         * Requirements:
         *
         * - `to` cannot be the zero address.
         * - `tokenId` token must be owned by `from`.
         *
         * Emits a {Transfer} event.
         */
        function _transfer(
            address from,
            address to,
            uint256 tokenId
        ) private {
            TokenOwnership memory prevOwnership = ownershipOf(tokenId);
            bool isApprovedOrOwner = (_msgSender() == prevOwnership.addr ||
                getApproved(tokenId) == _msgSender() ||
                isApprovedForAll(prevOwnership.addr, _msgSender()));
            require(isApprovedOrOwner, "ERC721A: transfer caller is not owner nor approved");
            require(prevOwnership.addr == from, "ERC721A: transfer from incorrect owner");
            require(to != address(0), "ERC721A: transfer to the zero address");
            _beforeTokenTransfers(from, to, tokenId, 1);
            // Clear approvals from the previous owner
            _approve(address(0), tokenId, prevOwnership.addr);
            _addressData[from].balance -= 1;
            _addressData[to].balance += 1;
            _ownerships[tokenId] = TokenOwnership(to, uint64(block.timestamp));
            // If the ownership slot of tokenId+1 is not explicitly set, that means the transfer initiator owns it.
            // Set the slot of tokenId+1 explicitly in storage to maintain correctness for ownerOf(tokenId+1) calls.
            uint256 nextTokenId = tokenId + 1;
            if (_ownerships[nextTokenId].addr == address(0)) {
                if (_exists(nextTokenId)) {
                    _ownerships[nextTokenId] = TokenOwnership(prevOwnership.addr, prevOwnership.startTimestamp);
                }
            }
            emit Transfer(from, to, tokenId);
            _afterTokenTransfers(from, to, tokenId, 1);
        }
        /**
         * @dev Approve `to` to operate on `tokenId`
         *
         * Emits a {Approval} event.
         */
        function _approve(
            address to,
            uint256 tokenId,
            address owner
        ) private {
            _tokenApprovals[tokenId] = to;
            emit Approval(owner, to, tokenId);
        }
        uint256 public nextOwnerToExplicitlySet = 0;
        /**
         * @dev Explicitly set `owners` to eliminate loops in future calls of ownerOf().
         */
        function _setOwnersExplicit(uint256 quantity) internal {
            uint256 oldNextOwnerToSet = nextOwnerToExplicitlySet;
            require(quantity > 0, "quantity must be nonzero");
            uint256 endIndex = oldNextOwnerToSet + quantity - 1;
            if (endIndex > currentIndex - 1) {
                endIndex = currentIndex - 1;
            }
            // We know if the last one in the group exists, all in the group exist, due to serial ordering.
            require(_exists(endIndex), "not enough minted yet for this cleanup");
            for (uint256 i = oldNextOwnerToSet; i <= endIndex; i++) {
                if (_ownerships[i].addr == address(0)) {
                    TokenOwnership memory ownership = ownershipOf(i);
                    _ownerships[i] = TokenOwnership(ownership.addr, ownership.startTimestamp);
                }
            }
            nextOwnerToExplicitlySet = endIndex + 1;
        }
        /**
         * @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(to).onERC721Received.selector;
                } catch (bytes memory reason) {
                    if (reason.length == 0) {
                        revert("ERC721A: transfer to non ERC721Receiver implementer");
                    } else {
                        assembly {
                            revert(add(32, reason), mload(reason))
                        }
                    }
                }
            } else {
                return true;
            }
        }
        /**
         * @dev Hook that is called before a set of serially-ordered token ids are about to be transferred. This includes minting.
         *
         * startTokenId - the first token id to be transferred
         * quantity - the amount to be transferred
         *
         * Calling conditions:
         *
         * - When `from` and `to` are both non-zero, ``from``'s `tokenId` will be
         * transferred to `to`.
         * - When `from` is zero, `tokenId` will be minted for `to`.
         */
        function _beforeTokenTransfers(
            address from,
            address to,
            uint256 startTokenId,
            uint256 quantity
        ) internal virtual {}
        /**
         * @dev Hook that is called after a set of serially-ordered token ids have been transferred. This includes
         * minting.
         *
         * startTokenId - the first token id to be transferred
         * quantity - the amount to be transferred
         *
         * Calling conditions:
         *
         * - when `from` and `to` are both non-zero.
         * - `from` and `to` are never both zero.
         */
        function _afterTokenTransfers(
            address from,
            address to,
            uint256 startTokenId,
            uint256 quantity
        ) internal virtual {}
    }
    // 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;
    /**
     * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
     *
     * These functions can be used to verify that a message was signed by the holder
     * of the private keys of a given address.
     */
    library ECDSA {
        /**
         * @dev Returns the address that signed a hashed message (`hash`) with
         * `signature`. This address can then be used for verification purposes.
         *
         * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
         * this function rejects them by requiring the `s` value to be in the lower
         * half order, and the `v` value to be either 27 or 28.
         *
         * IMPORTANT: `hash` _must_ be the result of a hash operation for the
         * verification to be secure: it is possible to craft signatures that
         * recover to arbitrary addresses for non-hashed data. A safe way to ensure
         * this is by receiving a hash of the original message (which may otherwise
         * be too long), and then calling {toEthSignedMessageHash} on it.
         *
         * Documentation for signature generation:
         * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
         * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
         */
        function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
            // Check the signature length
            // - case 65: r,s,v signature (standard)
            // - case 64: r,vs signature (cf https://eips.ethereum.org/EIPS/eip-2098) _Available since v4.1._
            if (signature.length == 65) {
                bytes32 r;
                bytes32 s;
                uint8 v;
                // ecrecover takes the signature parameters, and the only way to get them
                // currently is to use assembly.
                assembly {
                    r := mload(add(signature, 0x20))
                    s := mload(add(signature, 0x40))
                    v := byte(0, mload(add(signature, 0x60)))
                }
                return recover(hash, v, r, s);
            } else if (signature.length == 64) {
                bytes32 r;
                bytes32 vs;
                // ecrecover takes the signature parameters, and the only way to get them
                // currently is to use assembly.
                assembly {
                    r := mload(add(signature, 0x20))
                    vs := mload(add(signature, 0x40))
                }
                return recover(hash, r, vs);
            } else {
                revert("ECDSA: invalid signature length");
            }
        }
        /**
         * @dev Overload of {ECDSA-recover} that receives the `r` and `vs` short-signature fields separately.
         *
         * See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
         *
         * _Available since v4.2._
         */
        function recover(
            bytes32 hash,
            bytes32 r,
            bytes32 vs
        ) internal pure returns (address) {
            bytes32 s;
            uint8 v;
            assembly {
                s := and(vs, 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff)
                v := add(shr(255, vs), 27)
            }
            return recover(hash, v, r, s);
        }
        /**
         * @dev Overload of {ECDSA-recover} that receives the `v`, `r` and `s` signature fields separately.
         */
        function recover(
            bytes32 hash,
            uint8 v,
            bytes32 r,
            bytes32 s
        ) internal pure returns (address) {
            // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
            // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
            // the valid range for s in (281): 0 < s < secp256k1n ÷ 2 + 1, and for v in (282): v ∈ {27, 28}. Most
            // signatures from current libraries generate a unique signature with an s-value in the lower half order.
            //
            // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
            // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
            // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
            // these malleable signatures as well.
            require(
                uint256(s) <= 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0,
                "ECDSA: invalid signature 's' value"
            );
            require(v == 27 || v == 28, "ECDSA: invalid signature 'v' value");
            // If the signature is valid (and not malleable), return the signer address
            address signer = ecrecover(hash, v, r, s);
            require(signer != address(0), "ECDSA: invalid signature");
            return signer;
        }
        /**
         * @dev Returns an Ethereum Signed Message, created from a `hash`. This
         * produces hash corresponding to the one signed with the
         * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
         * JSON-RPC method as part of EIP-191.
         *
         * See {recover}.
         */
        function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
            // 32 is the length in bytes of hash,
            // enforced by the type signature above
            return keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\
    32", hash));
        }
        /**
         * @dev Returns an Ethereum Signed Typed Data, created from a
         * `domainSeparator` and a `structHash`. This produces hash corresponding
         * to the one signed with the
         * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
         * JSON-RPC method as part of EIP-712.
         *
         * See {recover}.
         */
        function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
            return keccak256(abi.encodePacked("\\x19\\x01", domainSeparator, structHash));
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "../utils/Address.sol";
    import "../utils/Context.sol";
    import "../utils/math/SafeMath.sol";
    /**
     * @title PaymentSplitter
     * @dev This contract allows to split Ether payments among a group of accounts. The sender does not need to be aware
     * that the Ether will be split in this way, since it is handled transparently by the contract.
     *
     * The split can be in equal parts or in any other arbitrary proportion. The way this is specified is by assigning each
     * account to a number of shares. Of all the Ether that this contract receives, each account will then be able to claim
     * an amount proportional to the percentage of total shares they were assigned.
     *
     * `PaymentSplitter` follows a _pull payment_ model. This means that payments are not automatically forwarded to the
     * accounts but kept in this contract, and the actual transfer is triggered as a separate step by calling the {release}
     * function.
     */
    contract PaymentSplitter is Context {
        event PayeeAdded(address account, uint256 shares);
        event PaymentReleased(address to, uint256 amount);
        event PaymentReceived(address from, uint256 amount);
        uint256 private _totalShares;
        uint256 private _totalReleased;
        mapping(address => uint256) private _shares;
        mapping(address => uint256) private _released;
        address[] private _payees;
        /**
         * @dev Creates an instance of `PaymentSplitter` where each account in `payees` is assigned the number of shares at
         * the matching position in the `shares` array.
         *
         * All addresses in `payees` must be non-zero. Both arrays must have the same non-zero length, and there must be no
         * duplicates in `payees`.
         */
        constructor(address[] memory payees, uint256[] memory shares_) payable {
            require(payees.length == shares_.length, "PaymentSplitter: payees and shares length mismatch");
            require(payees.length > 0, "PaymentSplitter: no payees");
            for (uint256 i = 0; i < payees.length; i++) {
                _addPayee(payees[i], shares_[i]);
            }
        }
        /**
         * @dev The Ether received will be logged with {PaymentReceived} events. Note that these events are not fully
         * reliable: it's possible for a contract to receive Ether without triggering this function. This only affects the
         * reliability of the events, and not the actual splitting of Ether.
         *
         * To learn more about this see the Solidity documentation for
         * https://solidity.readthedocs.io/en/latest/contracts.html#fallback-function[fallback
         * functions].
         */
        receive() external payable virtual {
            emit PaymentReceived(_msgSender(), msg.value);
        }
        /**
         * @dev Getter for the total shares held by payees.
         */
        function totalShares() public view returns (uint256) {
            return _totalShares;
        }
        /**
         * @dev Getter for the total amount of Ether already released.
         */
        function totalReleased() public view returns (uint256) {
            return _totalReleased;
        }
        /**
         * @dev Getter for the amount of shares held by an account.
         */
        function shares(address account) public view returns (uint256) {
            return _shares[account];
        }
        /**
         * @dev Getter for the amount of Ether already released to a payee.
         */
        function released(address account) public view returns (uint256) {
            return _released[account];
        }
        /**
         * @dev Getter for the address of the payee number `index`.
         */
        function payee(uint256 index) public view returns (address) {
            return _payees[index];
        }
        /**
         * @dev Triggers a transfer to `account` of the amount of Ether they are owed, according to their percentage of the
         * total shares and their previous withdrawals.
         */
        function release(address payable account) public virtual {
            require(_shares[account] > 0, "PaymentSplitter: account has no shares");
            uint256 totalReceived = address(this).balance + _totalReleased;
            uint256 payment = (totalReceived * _shares[account]) / _totalShares - _released[account];
            require(payment != 0, "PaymentSplitter: account is not due payment");
            _released[account] = _released[account] + payment;
            _totalReleased = _totalReleased + payment;
            Address.sendValue(account, payment);
            emit PaymentReleased(account, payment);
        }
        /**
         * @dev Add a new payee to the contract.
         * @param account The address of the payee to add.
         * @param shares_ The number of shares owned by the payee.
         */
        function _addPayee(address account, uint256 shares_) private {
            require(account != address(0), "PaymentSplitter: account is the zero address");
            require(shares_ > 0, "PaymentSplitter: shares are 0");
            require(_shares[account] == 0, "PaymentSplitter: account already has shares");
            _payees.push(account);
            _shares[account] = shares_;
            _totalShares = _totalShares + shares_;
            emit PayeeAdded(account, shares_);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev Contract module that helps prevent reentrant calls to a function.
     *
     * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
     * available, which can be applied to functions to make sure there are no nested
     * (reentrant) calls to them.
     *
     * Note that because there is a single `nonReentrant` guard, functions marked as
     * `nonReentrant` may not call one another. This can be worked around by making
     * those functions `private`, and then adding `external` `nonReentrant` entry
     * points to them.
     *
     * TIP: If you would like to learn more about reentrancy and alternative ways
     * to protect against it, check out our blog post
     * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
     */
    abstract contract ReentrancyGuard {
        // Booleans are more expensive than uint256 or any type that takes up a full
        // word because each write operation emits an extra SLOAD to first read the
        // slot's contents, replace the bits taken up by the boolean, and then write
        // back. This is the compiler's defense against contract upgrades and
        // pointer aliasing, and it cannot be disabled.
        // The values being non-zero value makes deployment a bit more expensive,
        // but in exchange the refund on every call to nonReentrant will be lower in
        // amount. Since refunds are capped to a percentage of the total
        // transaction's gas, it is best to keep them low in cases like this one, to
        // increase the likelihood of the full refund coming into effect.
        uint256 private constant _NOT_ENTERED = 1;
        uint256 private constant _ENTERED = 2;
        uint256 private _status;
        constructor() {
            _status = _NOT_ENTERED;
        }
        /**
         * @dev Prevents a contract from calling itself, directly or indirectly.
         * Calling a `nonReentrant` function from another `nonReentrant`
         * function is not supported. It is possible to prevent this from happening
         * by making the `nonReentrant` function external, and make it call a
         * `private` function that does the actual work.
         */
        modifier nonReentrant() {
            // On the first call to nonReentrant, _notEntered will be true
            require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
            // Any calls to nonReentrant after this point will fail
            _status = _ENTERED;
            _;
            // By storing the original value once again, a refund is triggered (see
            // https://eips.ethereum.org/EIPS/eip-2200)
            _status = _NOT_ENTERED;
        }
    }
    // 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;
    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;
    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;
    /**
     * @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);
        }
        function _verifyCallResult(
            bool success,
            bytes memory returndata,
            string memory errorMessage
        ) private 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;
    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;
    // 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;
            }
        }
    }