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{
  "language": "Solidity",
  "sources": {
    "agreement.sol": {
      "content": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.4;\n\nimport \"Strings.sol\";\nimport \"ERC721A.sol\";\nimport \"Base64.sol\";\n\ncontract Agreement is ERC721A {\n    using Strings for uint160;\n    using Strings for uint256;\n\n    string internal constant p =\n        '<p align=\"left\" style= \"white-space:pre-wrap; line-height: 35px; font-family:Courier;\">';\n    string internal constant p$ = \"</text></foreignObject>\";\n\n    struct AgreementNFT {\n        string name;\n        string terms;\n        address partyA;\n        address partyB;\n        address asset;\n        uint256 assetId;\n        uint256 signDate;\n        uint256 dueDate;\n        bool signed;\n    }\n\n    AgreementNFT[] private nft;\n\n    modifier tokenExist(uint256 tokenId) {\n        require(_exists(tokenId), \"Nonexistent token\");\n        _;\n    }\n\n    constructor() ERC721A(\"Agreement Manager\", \"AGRM\") {}\n\n    function create(\n        string calldata _name,\n        string calldata _terms,\n        address _party,\n        address _asset,\n        uint256 _id,\n        uint256 _due\n    ) external {\n        require(\n            _party == IERC721(_asset).ownerOf(_id),\n            \"party-B is not asset owner\"\n        );\n        nft.push(\n            AgreementNFT(\n                _name,\n                _terms,\n                msg.sender,\n                _party,\n                _asset,\n                _id,\n                block.timestamp,\n                _due,\n                false\n            )\n        );\n\n        _mint(msg.sender, 1);\n    }\n\n    function sign(uint256 tokenId) public tokenExist(tokenId) {\n        _verify(msg.sender, tokenId);\n    }\n\n    function tokenURI(uint256 tokenId)\n        public\n        view\n        virtual\n        override\n        tokenExist(tokenId)\n        returns (string memory)\n    {\n        bool signed = nft[tokenId].signed;\n        string memory status = nft[tokenId].signed ? \"Signed\" : \"Pending\";\n        if (block.timestamp >= nft[tokenId].dueDate) {\n            status = \"Expired\";\n            signed = false;\n        }\n        if (\n            nft[tokenId].partyB !=\n            IERC721(nft[tokenId].asset).ownerOf(nft[tokenId].assetId)\n        ) {\n            status = \"Asset Lost\";\n            signed = false;\n        }\n\n        bytes memory meta = abi.encodePacked(\n            '{\"name\": \"',\n            nft[tokenId].name,\n            '\", \"description\": \"The Agreement between [',\n            uint160(nft[tokenId].partyA).toHexString(),\n            \"] and [\",\n            uint160(nft[tokenId].partyB).toHexString(),\n            \"] with Asset {\",\n            uint160(nft[tokenId].asset).toHexString(),\n            \"#\",\n            nft[tokenId].assetId.toString(),\n            '}\",'\n        );\n        meta = abi.encodePacked(\n            meta,\n            '\"image_data\": \"data:image/svg+xml;base64,',\n            Base64.encode(abi.encodePacked(_nft_image(signed, tokenId))),\n            '\", \"designer\": \"drzu.xyz\",',\n            '\"attributes\": [{\"trait_type\": \"SIGN-DATE\", \"value\": \"',\n            nft[tokenId].signDate.toString(),\n            '\"},{\"trait_type\": \"DUE-DATE\", \"value\": \"',\n            nft[tokenId].dueDate.toString(),\n            '\"},',\n            '{\"trait_type\": \"STATUS\", \"value\": \"',\n            status,\n            '\"}]}'\n        );\n\n        return\n            string(\n                abi.encodePacked(\n                    \"data:application/json;base64,\",\n                    Base64.encode(meta)\n                )\n            );\n    }\n\n    function terms(uint256 tokenId)\n        public\n        view\n        tokenExist(tokenId)\n        returns (string memory)\n    {\n        require(\n            msg.sender == nft[tokenId].partyA ||\n                msg.sender == nft[tokenId].partyB,\n            \"Only contract party can view contract terms\"\n        );\n\n        return string(nft[tokenId].terms);\n    }\n\n    function _nft_image(bool signed, uint256 tokenId)\n        internal\n        view\n        returns (bytes memory)\n    {\n        bytes memory ret = abi.encodePacked(\n            '<svg width=\"500\" height=\"500\" viewBox=\"0 0 500 500\" ',\n            signed\n                ? 'style=\"background-color:darkgreen\"'\n                : 'style=\"background-color:darkred\"',\n            ' xml:space=\"preserve\" xmlns=\"http://www.w3.org/2000/svg\"><text x=\"250\" y=\"80\" style=\"text-anchor:middle;fill:white;font-size:40px\">CONTRACT</text><text x=\"250\" y=\"120\" style=\"text-anchor:middle;fill:white;font-size:12px\">BETWEEN</text><text x=\"250\" y=\"160\" style=\"text-anchor:middle;fill:white;font-size:24px\">PARTY A:</text><text x=\"250\" y=\"200\" style=\"text-anchor:middle;fill:white;font-size:16px\">[',\n            uint160(nft[tokenId].partyA).toHexString(),\n            ']</text><text x=\"250\" y=\"240\" style=\"text-anchor:middle;fill:white;font-size:12px\">AND</text><text x=\"250\" y=\"280\" style=\"text-anchor:middle;fill:white;font-size:24px\">PARTY B:</text><text x=\"250\" y=\"320\" style=\"text-anchor:middle;fill:white;font-size:16px\">[',\n            uint160(nft[tokenId].partyB).toHexString(),\n            ']</text><text x=\"250\" y=\"360\" style=\"text-anchor:middle;fill:white;font-size:24px\">WITH ASSET:</text><text x=\"250\" y=\"400\" style=\"text-anchor:middle;fill:white;font-size:16px\">{',\n            uint160(nft[tokenId].asset).toHexString(),\n            \"#\",\n            nft[tokenId].assetId.toString()\n        );\n        return\n            abi.encodePacked(\n                ret,\n                '}</text><text x=\"250\" y=\"460\" style=\"text-anchor:middle;fill:white;font-size:40px\">',\n                signed ? \"VALID\" : \"INVALID\",\n                \"</text></svg>\"\n            );\n    }\n\n    function _verify(address _party, uint256 tokenId) internal {\n        require(_party == nft[tokenId].partyB, \"signer is not partyB\");\n        require(\n            _party == IERC721(nft[tokenId].asset).ownerOf(nft[tokenId].assetId),\n            \"party-B is not asset owner\"\n        );\n        nft[tokenId].signed = true;\n    }\n}\n"
    },
    "Strings.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/Strings.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev String operations.\n */\nlibrary Strings {\n    bytes16 private constant _HEX_SYMBOLS = \"0123456789abcdef\";\n\n    /**\n     * @dev Converts a `uint256` to its ASCII `string` decimal representation.\n     */\n    function toString(uint256 value) internal pure returns (string memory) {\n        // Inspired by OraclizeAPI's implementation - MIT licence\n        // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol\n\n        if (value == 0) {\n            return \"0\";\n        }\n        uint256 temp = value;\n        uint256 digits;\n        while (temp != 0) {\n            digits++;\n            temp /= 10;\n        }\n        bytes memory buffer = new bytes(digits);\n        while (value != 0) {\n            digits -= 1;\n            buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));\n            value /= 10;\n        }\n        return string(buffer);\n    }\n\n    /**\n     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.\n     */\n    function toHexString(uint256 value) internal pure returns (string memory) {\n        if (value == 0) {\n            return \"0x00\";\n        }\n        uint256 temp = value;\n        uint256 length = 0;\n        while (temp != 0) {\n            length++;\n            temp >>= 8;\n        }\n        return toHexString(value, length);\n    }\n\n    /**\n     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.\n     */\n    function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {\n        bytes memory buffer = new bytes(2 * length + 2);\n        buffer[0] = \"0\";\n        buffer[1] = \"x\";\n        for (uint256 i = 2 * length + 1; i > 1; --i) {\n            buffer[i] = _HEX_SYMBOLS[value & 0xf];\n            value >>= 4;\n        }\n        require(value == 0, \"Strings: hex length insufficient\");\n        return string(buffer);\n    }\n}\n"
    },
    "ERC721A.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// Creator: Chiru Labs\n\npragma solidity ^0.8.4;\n\nimport \"IERC721A.sol\";\nimport \"IERC721Receiver.sol\";\nimport \"Address.sol\";\nimport \"Context.sol\";\nimport \"Strings.sol\";\nimport \"ERC165.sol\";\n\n/**\n * @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including\n * the Metadata extension. Built to optimize for lower gas during batch mints.\n *\n * Assumes serials are sequentially minted starting at _startTokenId() (defaults to 0, e.g. 0, 1, 2, 3..).\n *\n * Assumes that an owner cannot have more than 2**64 - 1 (max value of uint64) of supply.\n *\n * Assumes that the maximum token id cannot exceed 2**256 - 1 (max value of uint256).\n */\ncontract ERC721A is Context, ERC165, IERC721A {\n    using Address for address;\n    using Strings for uint256;\n\n    // The tokenId of the next token to be minted.\n    uint256 internal _currentIndex;\n\n    // The number of tokens burned.\n    uint256 internal _burnCounter;\n\n    // Token name\n    string private _name;\n\n    // Token symbol\n    string private _symbol;\n\n    // Mapping from token ID to ownership details\n    // An empty struct value does not necessarily mean the token is unowned. See _ownershipOf implementation for details.\n    mapping(uint256 => TokenOwnership) internal _ownerships;\n\n    // Mapping owner address to address data\n    mapping(address => AddressData) private _addressData;\n\n    // Mapping from token ID to approved address\n    mapping(uint256 => address) private _tokenApprovals;\n\n    // Mapping from owner to operator approvals\n    mapping(address => mapping(address => bool)) private _operatorApprovals;\n\n    constructor(string memory name_, string memory symbol_) {\n        _name = name_;\n        _symbol = symbol_;\n        _currentIndex = _startTokenId();\n    }\n\n    /**\n     * To change the starting tokenId, please override this function.\n     */\n    function _startTokenId() internal view virtual returns (uint256) {\n        return 0;\n    }\n\n    /**\n     * @dev Burned tokens are calculated here, use _totalMinted() if you want to count just minted tokens.\n     */\n    function totalSupply() public view returns (uint256) {\n        // Counter underflow is impossible as _burnCounter cannot be incremented\n        // more than _currentIndex - _startTokenId() times\n        unchecked {\n            return _currentIndex - _burnCounter - _startTokenId();\n        }\n    }\n\n    /**\n     * Returns the total amount of tokens minted in the contract.\n     */\n    function _totalMinted() internal view returns (uint256) {\n        // Counter underflow is impossible as _currentIndex does not decrement,\n        // and it is initialized to _startTokenId()\n        unchecked {\n            return _currentIndex - _startTokenId();\n        }\n    }\n\n    /**\n     * @dev See {IERC165-supportsInterface}.\n     */\n    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {\n        return\n            interfaceId == type(IERC721).interfaceId ||\n            interfaceId == type(IERC721Metadata).interfaceId ||\n            super.supportsInterface(interfaceId);\n    }\n\n    /**\n     * @dev See {IERC721-balanceOf}.\n     */\n    function balanceOf(address owner) public view override returns (uint256) {\n        if (owner == address(0)) revert BalanceQueryForZeroAddress();\n        return uint256(_addressData[owner].balance);\n    }\n\n    /**\n     * Returns the number of tokens minted by `owner`.\n     */\n    function _numberMinted(address owner) internal view returns (uint256) {\n        return uint256(_addressData[owner].numberMinted);\n    }\n\n    /**\n     * Returns the number of tokens burned by or on behalf of `owner`.\n     */\n    function _numberBurned(address owner) internal view returns (uint256) {\n        return uint256(_addressData[owner].numberBurned);\n    }\n\n    /**\n     * Returns the auxillary data for `owner`. (e.g. number of whitelist mint slots used).\n     */\n    function _getAux(address owner) internal view returns (uint64) {\n        return _addressData[owner].aux;\n    }\n\n    /**\n     * Sets the auxillary data for `owner`. (e.g. number of whitelist mint slots used).\n     * If there are multiple variables, please pack them into a uint64.\n     */\n    function _setAux(address owner, uint64 aux) internal {\n        _addressData[owner].aux = aux;\n    }\n\n    /**\n     * Gas spent here starts off proportional to the maximum mint batch size.\n     * It gradually moves to O(1) as tokens get transferred around in the collection over time.\n     */\n    function _ownershipOf(uint256 tokenId) internal view returns (TokenOwnership memory) {\n        uint256 curr = tokenId;\n\n        unchecked {\n            if (_startTokenId() <= curr && curr < _currentIndex) {\n                TokenOwnership memory ownership = _ownerships[curr];\n                if (!ownership.burned) {\n                    if (ownership.addr != address(0)) {\n                        return ownership;\n                    }\n                    // Invariant:\n                    // There will always be an ownership that has an address and is not burned\n                    // before an ownership that does not have an address and is not burned.\n                    // Hence, curr will not underflow.\n                    while (true) {\n                        curr--;\n                        ownership = _ownerships[curr];\n                        if (ownership.addr != address(0)) {\n                            return ownership;\n                        }\n                    }\n                }\n            }\n        }\n        revert OwnerQueryForNonexistentToken();\n    }\n\n    /**\n     * @dev See {IERC721-ownerOf}.\n     */\n    function ownerOf(uint256 tokenId) public view override returns (address) {\n        return _ownershipOf(tokenId).addr;\n    }\n\n    /**\n     * @dev See {IERC721Metadata-name}.\n     */\n    function name() public view virtual override returns (string memory) {\n        return _name;\n    }\n\n    /**\n     * @dev See {IERC721Metadata-symbol}.\n     */\n    function symbol() public view virtual override returns (string memory) {\n        return _symbol;\n    }\n\n    /**\n     * @dev See {IERC721Metadata-tokenURI}.\n     */\n    function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {\n        if (!_exists(tokenId)) revert URIQueryForNonexistentToken();\n\n        string memory baseURI = _baseURI();\n        return bytes(baseURI).length != 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : '';\n    }\n\n    /**\n     * @dev Base URI for computing {tokenURI}. If set, the resulting URI for each\n     * token will be the concatenation of the `baseURI` and the `tokenId`. Empty\n     * by default, can be overriden in child contracts.\n     */\n    function _baseURI() internal view virtual returns (string memory) {\n        return '';\n    }\n\n    /**\n     * @dev See {IERC721-approve}.\n     */\n    function approve(address to, uint256 tokenId) public override {\n        address owner = ERC721A.ownerOf(tokenId);\n        if (to == owner) revert ApprovalToCurrentOwner();\n\n        if (_msgSender() != owner && !isApprovedForAll(owner, _msgSender())) {\n            revert ApprovalCallerNotOwnerNorApproved();\n        }\n\n        _approve(to, tokenId, owner);\n    }\n\n    /**\n     * @dev See {IERC721-getApproved}.\n     */\n    function getApproved(uint256 tokenId) public view override returns (address) {\n        if (!_exists(tokenId)) revert ApprovalQueryForNonexistentToken();\n\n        return _tokenApprovals[tokenId];\n    }\n\n    /**\n     * @dev See {IERC721-setApprovalForAll}.\n     */\n    function setApprovalForAll(address operator, bool approved) public virtual override {\n        if (operator == _msgSender()) revert ApproveToCaller();\n\n        _operatorApprovals[_msgSender()][operator] = approved;\n        emit ApprovalForAll(_msgSender(), operator, approved);\n    }\n\n    /**\n     * @dev See {IERC721-isApprovedForAll}.\n     */\n    function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {\n        return _operatorApprovals[owner][operator];\n    }\n\n    /**\n     * @dev See {IERC721-transferFrom}.\n     */\n    function transferFrom(\n        address from,\n        address to,\n        uint256 tokenId\n    ) public virtual override {\n        _transfer(from, to, tokenId);\n    }\n\n    /**\n     * @dev See {IERC721-safeTransferFrom}.\n     */\n    function safeTransferFrom(\n        address from,\n        address to,\n        uint256 tokenId\n    ) public virtual override {\n        safeTransferFrom(from, to, tokenId, '');\n    }\n\n    /**\n     * @dev See {IERC721-safeTransferFrom}.\n     */\n    function safeTransferFrom(\n        address from,\n        address to,\n        uint256 tokenId,\n        bytes memory _data\n    ) public virtual override {\n        _transfer(from, to, tokenId);\n        if (to.isContract() && !_checkContractOnERC721Received(from, to, tokenId, _data)) {\n            revert TransferToNonERC721ReceiverImplementer();\n        }\n    }\n\n    /**\n     * @dev Returns whether `tokenId` exists.\n     *\n     * Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.\n     *\n     * Tokens start existing when they are minted (`_mint`),\n     */\n    function _exists(uint256 tokenId) internal view returns (bool) {\n        return _startTokenId() <= tokenId && tokenId < _currentIndex && !_ownerships[tokenId].burned;\n    }\n\n    /**\n     * @dev Equivalent to `_safeMint(to, quantity, '')`.\n     */\n    function _safeMint(address to, uint256 quantity) internal {\n        _safeMint(to, quantity, '');\n    }\n\n    /**\n     * @dev Safely mints `quantity` tokens and transfers them to `to`.\n     *\n     * Requirements:\n     *\n     * - If `to` refers to a smart contract, it must implement\n     *   {IERC721Receiver-onERC721Received}, which is called for each safe transfer.\n     * - `quantity` must be greater than 0.\n     *\n     * Emits a {Transfer} event.\n     */\n    function _safeMint(\n        address to,\n        uint256 quantity,\n        bytes memory _data\n    ) internal {\n        uint256 startTokenId = _currentIndex;\n        if (to == address(0)) revert MintToZeroAddress();\n        if (quantity == 0) revert MintZeroQuantity();\n\n        _beforeTokenTransfers(address(0), to, startTokenId, quantity);\n\n        // Overflows are incredibly unrealistic.\n        // balance or numberMinted overflow if current value of either + quantity > 1.8e19 (2**64) - 1\n        // updatedIndex overflows if _currentIndex + quantity > 1.2e77 (2**256) - 1\n        unchecked {\n            _addressData[to].balance += uint64(quantity);\n            _addressData[to].numberMinted += uint64(quantity);\n\n            _ownerships[startTokenId].addr = to;\n            _ownerships[startTokenId].startTimestamp = uint64(block.timestamp);\n\n            uint256 updatedIndex = startTokenId;\n            uint256 end = updatedIndex + quantity;\n\n            if (to.isContract()) {\n                do {\n                    emit Transfer(address(0), to, updatedIndex);\n                    if (!_checkContractOnERC721Received(address(0), to, updatedIndex++, _data)) {\n                        revert TransferToNonERC721ReceiverImplementer();\n                    }\n                } while (updatedIndex != end);\n                // Reentrancy protection\n                if (_currentIndex != startTokenId) revert();\n            } else {\n                do {\n                    emit Transfer(address(0), to, updatedIndex++);\n                } while (updatedIndex != end);\n            }\n            _currentIndex = updatedIndex;\n        }\n        _afterTokenTransfers(address(0), to, startTokenId, quantity);\n    }\n\n    /**\n     * @dev Mints `quantity` tokens and transfers them to `to`.\n     *\n     * Requirements:\n     *\n     * - `to` cannot be the zero address.\n     * - `quantity` must be greater than 0.\n     *\n     * Emits a {Transfer} event.\n     */\n    function _mint(address to, uint256 quantity) internal {\n        uint256 startTokenId = _currentIndex;\n        if (to == address(0)) revert MintToZeroAddress();\n        if (quantity == 0) revert MintZeroQuantity();\n\n        _beforeTokenTransfers(address(0), to, startTokenId, quantity);\n\n        // Overflows are incredibly unrealistic.\n        // balance or numberMinted overflow if current value of either + quantity > 1.8e19 (2**64) - 1\n        // updatedIndex overflows if _currentIndex + quantity > 1.2e77 (2**256) - 1\n        unchecked {\n            _addressData[to].balance += uint64(quantity);\n            _addressData[to].numberMinted += uint64(quantity);\n\n            _ownerships[startTokenId].addr = to;\n            _ownerships[startTokenId].startTimestamp = uint64(block.timestamp);\n\n            uint256 updatedIndex = startTokenId;\n            uint256 end = updatedIndex + quantity;\n\n            do {\n                emit Transfer(address(0), to, updatedIndex++);\n            } while (updatedIndex != end);\n\n            _currentIndex = updatedIndex;\n        }\n        _afterTokenTransfers(address(0), to, startTokenId, quantity);\n    }\n\n    /**\n     * @dev Transfers `tokenId` from `from` to `to`.\n     *\n     * Requirements:\n     *\n     * - `to` cannot be the zero address.\n     * - `tokenId` token must be owned by `from`.\n     *\n     * Emits a {Transfer} event.\n     */\n    function _transfer(\n        address from,\n        address to,\n        uint256 tokenId\n    ) private {\n        TokenOwnership memory prevOwnership = _ownershipOf(tokenId);\n\n        if (prevOwnership.addr != from) revert TransferFromIncorrectOwner();\n\n        bool isApprovedOrOwner = (_msgSender() == from ||\n            isApprovedForAll(from, _msgSender()) ||\n            getApproved(tokenId) == _msgSender());\n\n        if (!isApprovedOrOwner) revert TransferCallerNotOwnerNorApproved();\n        if (to == address(0)) revert TransferToZeroAddress();\n\n        _beforeTokenTransfers(from, to, tokenId, 1);\n\n        // Clear approvals from the previous owner\n        _approve(address(0), tokenId, from);\n\n        // Underflow of the sender's balance is impossible because we check for\n        // ownership above and the recipient's balance can't realistically overflow.\n        // Counter overflow is incredibly unrealistic as tokenId would have to be 2**256.\n        unchecked {\n            _addressData[from].balance -= 1;\n            _addressData[to].balance += 1;\n\n            TokenOwnership storage currSlot = _ownerships[tokenId];\n            currSlot.addr = to;\n            currSlot.startTimestamp = uint64(block.timestamp);\n\n            // If the ownership slot of tokenId+1 is not explicitly set, that means the transfer initiator owns it.\n            // Set the slot of tokenId+1 explicitly in storage to maintain correctness for ownerOf(tokenId+1) calls.\n            uint256 nextTokenId = tokenId + 1;\n            TokenOwnership storage nextSlot = _ownerships[nextTokenId];\n            if (nextSlot.addr == address(0)) {\n                // This will suffice for checking _exists(nextTokenId),\n                // as a burned slot cannot contain the zero address.\n                if (nextTokenId != _currentIndex) {\n                    nextSlot.addr = from;\n                    nextSlot.startTimestamp = prevOwnership.startTimestamp;\n                }\n            }\n        }\n\n        emit Transfer(from, to, tokenId);\n        _afterTokenTransfers(from, to, tokenId, 1);\n    }\n\n    /**\n     * @dev Equivalent to `_burn(tokenId, false)`.\n     */\n    function _burn(uint256 tokenId) internal virtual {\n        _burn(tokenId, false);\n    }\n\n    /**\n     * @dev Destroys `tokenId`.\n     * The approval is cleared when the token is burned.\n     *\n     * Requirements:\n     *\n     * - `tokenId` must exist.\n     *\n     * Emits a {Transfer} event.\n     */\n    function _burn(uint256 tokenId, bool approvalCheck) internal virtual {\n        TokenOwnership memory prevOwnership = _ownershipOf(tokenId);\n\n        address from = prevOwnership.addr;\n\n        if (approvalCheck) {\n            bool isApprovedOrOwner = (_msgSender() == from ||\n                isApprovedForAll(from, _msgSender()) ||\n                getApproved(tokenId) == _msgSender());\n\n            if (!isApprovedOrOwner) revert TransferCallerNotOwnerNorApproved();\n        }\n\n        _beforeTokenTransfers(from, address(0), tokenId, 1);\n\n        // Clear approvals from the previous owner\n        _approve(address(0), tokenId, from);\n\n        // Underflow of the sender's balance is impossible because we check for\n        // ownership above and the recipient's balance can't realistically overflow.\n        // Counter overflow is incredibly unrealistic as tokenId would have to be 2**256.\n        unchecked {\n            AddressData storage addressData = _addressData[from];\n            addressData.balance -= 1;\n            addressData.numberBurned += 1;\n\n            // Keep track of who burned the token, and the timestamp of burning.\n            TokenOwnership storage currSlot = _ownerships[tokenId];\n            currSlot.addr = from;\n            currSlot.startTimestamp = uint64(block.timestamp);\n            currSlot.burned = true;\n\n            // If the ownership slot of tokenId+1 is not explicitly set, that means the burn initiator owns it.\n            // Set the slot of tokenId+1 explicitly in storage to maintain correctness for ownerOf(tokenId+1) calls.\n            uint256 nextTokenId = tokenId + 1;\n            TokenOwnership storage nextSlot = _ownerships[nextTokenId];\n            if (nextSlot.addr == address(0)) {\n                // This will suffice for checking _exists(nextTokenId),\n                // as a burned slot cannot contain the zero address.\n                if (nextTokenId != _currentIndex) {\n                    nextSlot.addr = from;\n                    nextSlot.startTimestamp = prevOwnership.startTimestamp;\n                }\n            }\n        }\n\n        emit Transfer(from, address(0), tokenId);\n        _afterTokenTransfers(from, address(0), tokenId, 1);\n\n        // Overflow not possible, as _burnCounter cannot be exceed _currentIndex times.\n        unchecked {\n            _burnCounter++;\n        }\n    }\n\n    /**\n     * @dev Approve `to` to operate on `tokenId`\n     *\n     * Emits a {Approval} event.\n     */\n    function _approve(\n        address to,\n        uint256 tokenId,\n        address owner\n    ) private {\n        _tokenApprovals[tokenId] = to;\n        emit Approval(owner, to, tokenId);\n    }\n\n    /**\n     * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target contract.\n     *\n     * @param from address representing the previous owner of the given token ID\n     * @param to target address that will receive the tokens\n     * @param tokenId uint256 ID of the token to be transferred\n     * @param _data bytes optional data to send along with the call\n     * @return bool whether the call correctly returned the expected magic value\n     */\n    function _checkContractOnERC721Received(\n        address from,\n        address to,\n        uint256 tokenId,\n        bytes memory _data\n    ) private returns (bool) {\n        try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, _data) returns (bytes4 retval) {\n            return retval == IERC721Receiver(to).onERC721Received.selector;\n        } catch (bytes memory reason) {\n            if (reason.length == 0) {\n                revert TransferToNonERC721ReceiverImplementer();\n            } else {\n                assembly {\n                    revert(add(32, reason), mload(reason))\n                }\n            }\n        }\n    }\n\n    /**\n     * @dev Hook that is called before a set of serially-ordered token ids are about to be transferred. This includes minting.\n     * And also called before burning one token.\n     *\n     * startTokenId - the first token id to be transferred\n     * quantity - the amount to be transferred\n     *\n     * Calling conditions:\n     *\n     * - When `from` and `to` are both non-zero, `from`'s `tokenId` will be\n     * transferred to `to`.\n     * - When `from` is zero, `tokenId` will be minted for `to`.\n     * - When `to` is zero, `tokenId` will be burned by `from`.\n     * - `from` and `to` are never both zero.\n     */\n    function _beforeTokenTransfers(\n        address from,\n        address to,\n        uint256 startTokenId,\n        uint256 quantity\n    ) internal virtual {}\n\n    /**\n     * @dev Hook that is called after a set of serially-ordered token ids have been transferred. This includes\n     * minting.\n     * And also called after one token has been burned.\n     *\n     * startTokenId - the first token id to be transferred\n     * quantity - the amount to be transferred\n     *\n     * Calling conditions:\n     *\n     * - When `from` and `to` are both non-zero, `from`'s `tokenId` has been\n     * transferred to `to`.\n     * - When `from` is zero, `tokenId` has been minted for `to`.\n     * - When `to` is zero, `tokenId` has been burned by `from`.\n     * - `from` and `to` are never both zero.\n     */\n    function _afterTokenTransfers(\n        address from,\n        address to,\n        uint256 startTokenId,\n        uint256 quantity\n    ) internal virtual {}\n}\n"
    },
    "IERC721A.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// Creator: Chiru Labs\n\npragma solidity ^0.8.4;\n\nimport \"IERC721.sol\";\nimport \"IERC721Metadata.sol\";\n\n/**\n * @dev Interface of an ERC721A compliant contract.\n */\ninterface IERC721A is IERC721, IERC721Metadata {\n    error ApprovalCallerNotOwnerNorApproved();\n    error ApprovalQueryForNonexistentToken();\n    error ApproveToCaller();\n    error ApprovalToCurrentOwner();\n    error BalanceQueryForZeroAddress();\n    error MintToZeroAddress();\n    error MintZeroQuantity();\n    error OwnerQueryForNonexistentToken();\n    error TransferCallerNotOwnerNorApproved();\n    error TransferFromIncorrectOwner();\n    error TransferToNonERC721ReceiverImplementer();\n    error TransferToZeroAddress();\n    error URIQueryForNonexistentToken();\n\n    // Compiler will pack this into a single 256bit word.\n    struct TokenOwnership {\n        // The address of the owner.\n        address addr;\n        // Keeps track of the start time of ownership with minimal overhead for tokenomics.\n        uint64 startTimestamp;\n        // Whether the token has been burned.\n        bool burned;\n    }\n\n    // Compiler will pack this into a single 256bit word.\n    struct AddressData {\n        // Realistically, 2**64-1 is more than enough.\n        uint64 balance;\n        // Keeps track of mint count with minimal overhead for tokenomics.\n        uint64 numberMinted;\n        // Keeps track of burn count with minimal overhead for tokenomics.\n        uint64 numberBurned;\n        // For miscellaneous variable(s) pertaining to the address\n        // (e.g. number of whitelist mint slots used).\n        // If there are multiple variables, please pack them into a uint64.\n        uint64 aux;\n    }\n\n    /**\n     * @dev Returns the total amount of tokens stored by the contract.\n     * @dev Burned tokens are calculated here, use _totalMinted() if you want to count just minted tokens.\n     */\n    function totalSupply() external view returns (uint256);\n}\n"
    },
    "IERC721.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721.sol)\n\npragma solidity ^0.8.0;\n\nimport \"IERC165.sol\";\n\n/**\n * @dev Required interface of an ERC721 compliant contract.\n */\ninterface IERC721 is IERC165 {\n    /**\n     * @dev Emitted when `tokenId` token is transferred from `from` to `to`.\n     */\n    event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);\n\n    /**\n     * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.\n     */\n    event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);\n\n    /**\n     * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.\n     */\n    event ApprovalForAll(address indexed owner, address indexed operator, bool approved);\n\n    /**\n     * @dev Returns the number of tokens in ``owner``'s account.\n     */\n    function balanceOf(address owner) external view returns (uint256 balance);\n\n    /**\n     * @dev Returns the owner of the `tokenId` token.\n     *\n     * Requirements:\n     *\n     * - `tokenId` must exist.\n     */\n    function ownerOf(uint256 tokenId) external view returns (address owner);\n\n    /**\n     * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients\n     * are aware of the ERC721 protocol to prevent tokens from being forever locked.\n     *\n     * Requirements:\n     *\n     * - `from` cannot be the zero address.\n     * - `to` cannot be the zero address.\n     * - `tokenId` token must exist and be owned by `from`.\n     * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.\n     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.\n     *\n     * Emits a {Transfer} event.\n     */\n    function safeTransferFrom(\n        address from,\n        address to,\n        uint256 tokenId\n    ) external;\n\n    /**\n     * @dev Transfers `tokenId` token from `from` to `to`.\n     *\n     * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.\n     *\n     * Requirements:\n     *\n     * - `from` cannot be the zero address.\n     * - `to` cannot be the zero address.\n     * - `tokenId` token must be owned by `from`.\n     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.\n     *\n     * Emits a {Transfer} event.\n     */\n    function transferFrom(\n        address from,\n        address to,\n        uint256 tokenId\n    ) external;\n\n    /**\n     * @dev Gives permission to `to` to transfer `tokenId` token to another account.\n     * The approval is cleared when the token is transferred.\n     *\n     * Only a single account can be approved at a time, so approving the zero address clears previous approvals.\n     *\n     * Requirements:\n     *\n     * - The caller must own the token or be an approved operator.\n     * - `tokenId` must exist.\n     *\n     * Emits an {Approval} event.\n     */\n    function approve(address to, uint256 tokenId) external;\n\n    /**\n     * @dev Returns the account approved for `tokenId` token.\n     *\n     * Requirements:\n     *\n     * - `tokenId` must exist.\n     */\n    function getApproved(uint256 tokenId) external view returns (address operator);\n\n    /**\n     * @dev Approve or remove `operator` as an operator for the caller.\n     * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.\n     *\n     * Requirements:\n     *\n     * - The `operator` cannot be the caller.\n     *\n     * Emits an {ApprovalForAll} event.\n     */\n    function setApprovalForAll(address operator, bool _approved) external;\n\n    /**\n     * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.\n     *\n     * See {setApprovalForAll}\n     */\n    function isApprovedForAll(address owner, address operator) external view returns (bool);\n\n    /**\n     * @dev Safely transfers `tokenId` token from `from` to `to`.\n     *\n     * Requirements:\n     *\n     * - `from` cannot be the zero address.\n     * - `to` cannot be the zero address.\n     * - `tokenId` token must exist and be owned by `from`.\n     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.\n     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.\n     *\n     * Emits a {Transfer} event.\n     */\n    function safeTransferFrom(\n        address from,\n        address to,\n        uint256 tokenId,\n        bytes calldata data\n    ) external;\n}\n"
    },
    "IERC165.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Interface of the ERC165 standard, as defined in the\n * https://eips.ethereum.org/EIPS/eip-165[EIP].\n *\n * Implementers can declare support of contract interfaces, which can then be\n * queried by others ({ERC165Checker}).\n *\n * For an implementation, see {ERC165}.\n */\ninterface IERC165 {\n    /**\n     * @dev Returns true if this contract implements the interface defined by\n     * `interfaceId`. See the corresponding\n     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]\n     * to learn more about how these ids are created.\n     *\n     * This function call must use less than 30 000 gas.\n     */\n    function supportsInterface(bytes4 interfaceId) external view returns (bool);\n}\n"
    },
    "IERC721Metadata.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/IERC721Metadata.sol)\n\npragma solidity ^0.8.0;\n\nimport \"IERC721.sol\";\n\n/**\n * @title ERC-721 Non-Fungible Token Standard, optional metadata extension\n * @dev See https://eips.ethereum.org/EIPS/eip-721\n */\ninterface IERC721Metadata is IERC721 {\n    /**\n     * @dev Returns the token collection name.\n     */\n    function name() external view returns (string memory);\n\n    /**\n     * @dev Returns the token collection symbol.\n     */\n    function symbol() external view returns (string memory);\n\n    /**\n     * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.\n     */\n    function tokenURI(uint256 tokenId) external view returns (string memory);\n}\n"
    },
    "IERC721Receiver.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721Receiver.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @title ERC721 token receiver interface\n * @dev Interface for any contract that wants to support safeTransfers\n * from ERC721 asset contracts.\n */\ninterface IERC721Receiver {\n    /**\n     * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}\n     * by `operator` from `from`, this function is called.\n     *\n     * It must return its Solidity selector to confirm the token transfer.\n     * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.\n     *\n     * The selector can be obtained in Solidity with `IERC721.onERC721Received.selector`.\n     */\n    function onERC721Received(\n        address operator,\n        address from,\n        uint256 tokenId,\n        bytes calldata data\n    ) external returns (bytes4);\n}\n"
    },
    "Address.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/Address.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Collection of functions related to the address type\n */\nlibrary Address {\n    /**\n     * @dev Returns true if `account` is a contract.\n     *\n     * [IMPORTANT]\n     * ====\n     * It is unsafe to assume that an address for which this function returns\n     * false is an externally-owned account (EOA) and not a contract.\n     *\n     * Among others, `isContract` will return false for the following\n     * types of addresses:\n     *\n     *  - an externally-owned account\n     *  - a contract in construction\n     *  - an address where a contract will be created\n     *  - an address where a contract lived, but was destroyed\n     * ====\n     */\n    function isContract(address account) internal view returns (bool) {\n        // This method relies on extcodesize, which returns 0 for contracts in\n        // construction, since the code is only stored at the end of the\n        // constructor execution.\n\n        uint256 size;\n        assembly {\n            size := extcodesize(account)\n        }\n        return size > 0;\n    }\n\n    /**\n     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to\n     * `recipient`, forwarding all available gas and reverting on errors.\n     *\n     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost\n     * of certain opcodes, possibly making contracts go over the 2300 gas limit\n     * imposed by `transfer`, making them unable to receive funds via\n     * `transfer`. {sendValue} removes this limitation.\n     *\n     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].\n     *\n     * IMPORTANT: because control is transferred to `recipient`, care must be\n     * taken to not create reentrancy vulnerabilities. Consider using\n     * {ReentrancyGuard} or the\n     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].\n     */\n    function sendValue(address payable recipient, uint256 amount) internal {\n        require(address(this).balance >= amount, \"Address: insufficient balance\");\n\n        (bool success, ) = recipient.call{value: amount}(\"\");\n        require(success, \"Address: unable to send value, recipient may have reverted\");\n    }\n\n    /**\n     * @dev Performs a Solidity function call using a low level `call`. A\n     * plain `call` is an unsafe replacement for a function call: use this\n     * function instead.\n     *\n     * If `target` reverts with a revert reason, it is bubbled up by this\n     * function (like regular Solidity function calls).\n     *\n     * Returns the raw returned data. To convert to the expected return value,\n     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].\n     *\n     * Requirements:\n     *\n     * - `target` must be a contract.\n     * - calling `target` with `data` must not revert.\n     *\n     * _Available since v3.1._\n     */\n    function functionCall(address target, bytes memory data) internal returns (bytes memory) {\n        return functionCall(target, data, \"Address: low-level call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with\n     * `errorMessage` as a fallback revert reason when `target` reverts.\n     *\n     * _Available since v3.1._\n     */\n    function functionCall(\n        address target,\n        bytes memory data,\n        string memory errorMessage\n    ) internal returns (bytes memory) {\n        return functionCallWithValue(target, data, 0, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but also transferring `value` wei to `target`.\n     *\n     * Requirements:\n     *\n     * - the calling contract must have an ETH balance of at least `value`.\n     * - the called Solidity function must be `payable`.\n     *\n     * _Available since v3.1._\n     */\n    function functionCallWithValue(\n        address target,\n        bytes memory data,\n        uint256 value\n    ) internal returns (bytes memory) {\n        return functionCallWithValue(target, data, value, \"Address: low-level call with value failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but\n     * with `errorMessage` as a fallback revert reason when `target` reverts.\n     *\n     * _Available since v3.1._\n     */\n    function functionCallWithValue(\n        address target,\n        bytes memory data,\n        uint256 value,\n        string memory errorMessage\n    ) internal returns (bytes memory) {\n        require(address(this).balance >= value, \"Address: insufficient balance for call\");\n        require(isContract(target), \"Address: call to non-contract\");\n\n        (bool success, bytes memory returndata) = target.call{value: value}(data);\n        return verifyCallResult(success, returndata, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but performing a static call.\n     *\n     * _Available since v3.3._\n     */\n    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {\n        return functionStaticCall(target, data, \"Address: low-level static call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n     * but performing a static call.\n     *\n     * _Available since v3.3._\n     */\n    function functionStaticCall(\n        address target,\n        bytes memory data,\n        string memory errorMessage\n    ) internal view returns (bytes memory) {\n        require(isContract(target), \"Address: static call to non-contract\");\n\n        (bool success, bytes memory returndata) = target.staticcall(data);\n        return verifyCallResult(success, returndata, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but performing a delegate call.\n     *\n     * _Available since v3.4._\n     */\n    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {\n        return functionDelegateCall(target, data, \"Address: low-level delegate call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n     * but performing a delegate call.\n     *\n     * _Available since v3.4._\n     */\n    function functionDelegateCall(\n        address target,\n        bytes memory data,\n        string memory errorMessage\n    ) internal returns (bytes memory) {\n        require(isContract(target), \"Address: delegate call to non-contract\");\n\n        (bool success, bytes memory returndata) = target.delegatecall(data);\n        return verifyCallResult(success, returndata, errorMessage);\n    }\n\n    /**\n     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the\n     * revert reason using the provided one.\n     *\n     * _Available since v4.3._\n     */\n    function verifyCallResult(\n        bool success,\n        bytes memory returndata,\n        string memory errorMessage\n    ) internal pure returns (bytes memory) {\n        if (success) {\n            return returndata;\n        } else {\n            // Look for revert reason and bubble it up if present\n            if (returndata.length > 0) {\n                // The easiest way to bubble the revert reason is using memory via assembly\n\n                assembly {\n                    let returndata_size := mload(returndata)\n                    revert(add(32, returndata), returndata_size)\n                }\n            } else {\n                revert(errorMessage);\n            }\n        }\n    }\n}\n"
    },
    "Context.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Provides information about the current execution context, including the\n * sender of the transaction and its data. While these are generally available\n * via msg.sender and msg.data, they should not be accessed in such a direct\n * manner, since when dealing with meta-transactions the account sending and\n * paying for execution may not be the actual sender (as far as an application\n * is concerned).\n *\n * This contract is only required for intermediate, library-like contracts.\n */\nabstract contract Context {\n    function _msgSender() internal view virtual returns (address) {\n        return msg.sender;\n    }\n\n    function _msgData() internal view virtual returns (bytes calldata) {\n        return msg.data;\n    }\n}\n"
    },
    "ERC165.sol": {
      "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)\n\npragma solidity ^0.8.0;\n\nimport \"IERC165.sol\";\n\n/**\n * @dev Implementation of the {IERC165} interface.\n *\n * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check\n * for the additional interface id that will be supported. For example:\n *\n * ```solidity\n * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {\n *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);\n * }\n * ```\n *\n * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.\n */\nabstract contract ERC165 is IERC165 {\n    /**\n     * @dev See {IERC165-supportsInterface}.\n     */\n    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {\n        return interfaceId == type(IERC165).interfaceId;\n    }\n}\n"
    },
    "Base64.sol": {
      "content": "// SPDX-License-Identifier: MIT\npragma solidity ^0.8.0;\n\n/// @title Base64\n/// @author Brecht Devos - <brecht@loopring.org>\n/// @notice Provides a function for encoding some bytes in base64\nlibrary Base64 {\n    string internal constant TABLE = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';\n\n    function encode(bytes memory data) internal pure returns (string memory) {\n        if (data.length == 0) return '';\n        \n        // load the table into memory\n        string memory table = TABLE;\n\n        // multiply by 4/3 rounded up\n        uint256 encodedLen = 4 * ((data.length + 2) / 3);\n\n        // add some extra buffer at the end required for the writing\n        string memory result = new string(encodedLen + 32);\n\n        assembly {\n            // set the actual output length\n            mstore(result, encodedLen)\n            \n            // prepare the lookup table\n            let tablePtr := add(table, 1)\n            \n            // input ptr\n            let dataPtr := data\n            let endPtr := add(dataPtr, mload(data))\n            \n            // result ptr, jump over length\n            let resultPtr := add(result, 32)\n            \n            // run over the input, 3 bytes at a time\n            for {} lt(dataPtr, endPtr) {}\n            {\n               dataPtr := add(dataPtr, 3)\n               \n               // read 3 bytes\n               let input := mload(dataPtr)\n               \n               // write 4 characters\n               mstore(resultPtr, shl(248, mload(add(tablePtr, and(shr(18, input), 0x3F)))))\n               resultPtr := add(resultPtr, 1)\n               mstore(resultPtr, shl(248, mload(add(tablePtr, and(shr(12, input), 0x3F)))))\n               resultPtr := add(resultPtr, 1)\n               mstore(resultPtr, shl(248, mload(add(tablePtr, and(shr( 6, input), 0x3F)))))\n               resultPtr := add(resultPtr, 1)\n               mstore(resultPtr, shl(248, mload(add(tablePtr, and(        input,  0x3F)))))\n               resultPtr := add(resultPtr, 1)\n            }\n            \n            // padding with '='\n            switch mod(mload(data), 3)\n            case 1 { mstore(sub(resultPtr, 2), shl(240, 0x3d3d)) }\n            case 2 { mstore(sub(resultPtr, 1), shl(248, 0x3d)) }\n        }\n        \n        return result;\n    }\n}"
    }
  },
  "settings": {
    "evmVersion": "istanbul",
    "optimizer": {
      "enabled": true,
      "runs": 200
    },
    "libraries": {
      "agreement.sol": {}
    },
    "outputSelection": {
      "*": {
        "*": [
          "evm.bytecode",
          "evm.deployedBytecode",
          "devdoc",
          "userdoc",
          "metadata",
          "abi"
        ]
      }
    }
  }
}