creation_sourcecode: {{
    "language": "Solidity",
    "sources": {
      "/contracts/BNFT.sol": {
        "content": "// SPDX-License-Identifier: MIT\npragma solidity 0.8.0;\n\nimport \"./BRC721Enumerable.sol\";\nimport \"@openzeppelin/contracts/security/Pausable.sol\";\nimport \"@openzeppelin/contracts/utils/Strings.sol\";\n\ncontract BNFT is BRC721Enumerable, Pausable {\n    using Strings for uint256;\n\n    string private baseURI;\n    address public owner;\n\n    constructor(\n        address admin_,\n        address owner_,\n        string memory baseURI_,\n        string memory name_,\n        string memory symbol_\n    ) BRC721(admin_, name_, symbol_) {\n        baseURI = string(abi.encodePacked(baseURI_, symbol_, \"/\"));\n        owner = owner_;\n    }\n\n    function _baseURI() internal view override returns (string memory) {\n        return baseURI;\n    }\n\n    /**\n     * override tokenURI(uint256), remove restrict for tokenId exist.\n     */\n    function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {\n        return string(abi.encodePacked(baseURI, tokenId.toString()));\n    }\n\n    function setOwner(address owner_) external onlyAdmin {\n        owner = owner_;\n    }\n\n    function setPause() external onlyAdmin {\n        _pause();\n    }\n\n    function unsetPause() external onlyAdmin {\n        _unpause();\n    }\n\n    function changeBaseURI(string memory newBaseURI) external onlyAdmin {\n        string memory symbol_ = symbol();\n        baseURI = string(abi.encodePacked(newBaseURI, symbol_, \"/\"));\n    }\n\n    /**\n     * @dev See {ERC721-_beforeTokenTransfer}.\n     *\n     * Requirements:\n     *\n     * - the contract must not be paused.\n     */\n    function _beforeTokenTransfer(\n        address from,\n        address to,\n        uint256 tokenId\n    ) internal virtual override {\n        super._beforeTokenTransfer(from, to, tokenId);\n\n        require(!paused(), \"BRC721Pausable: token transfer while paused\");\n    }\n}\n"
      },
      "/contracts/BRC721Enumerable.sol": {
        "content": "// SPDX-License-Identifier: MIT\npragma solidity 0.8.0;\n\nimport \"./BRC721.sol\";\n\nimport \"@openzeppelin/contracts/token/ERC721/extensions/IERC721Enumerable.sol\";\n\nabstract contract BRC721Enumerable is BRC721, IERC721Enumerable {\n    // Mapping from owner to list of owned token IDs\n    mapping(address => mapping(uint256 => uint256)) private _ownedTokens;\n\n    // Mapping from token ID to index of the owner tokens list\n    mapping(uint256 => uint256) private _ownedTokensIndex;\n\n    // Array with all token ids, used for enumeration\n    uint256[] private _allTokens;\n\n    // Mapping from token id to position in the allTokens array\n    mapping(uint256 => uint256) private _allTokensIndex;\n\n    /**\n     * @dev See {IERC165-supportsInterface}.\n     */\n    function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165, BRC721) returns (bool) {\n        return interfaceId == type(IERC721Enumerable).interfaceId\n        || super.supportsInterface(interfaceId);\n    }\n\n    /**\n     * @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.\n     */\n    function tokenOfOwnerByIndex(address owner, uint256 index) public view virtual override returns (uint256) {\n        require(index < BRC721.balanceOf(owner), \"ERC721Enumerable: owner index out of bounds\");\n        return _ownedTokens[owner][index];\n    }\n\n    /**\n     * @dev See {IERC721Enumerable-totalSupply}.\n     */\n    function totalSupply() public view virtual override returns (uint256) {\n        return _allTokens.length;\n    }\n\n    /**\n     * @dev See {IERC721Enumerable-tokenByIndex}.\n     */\n    function tokenByIndex(uint256 index) public view virtual override returns (uint256) {\n        require(index < BRC721Enumerable.totalSupply(), \"ERC721Enumerable: global index out of bounds\");\n        return _allTokens[index];\n    }\n\n    /**\n     * @dev Hook that is called before any token transfer. This includes minting\n     * and burning.\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, ``from``'s `tokenId` will be burned.\n     * - `from` cannot be the zero address.\n     * - `to` cannot be the zero address.\n     *\n     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].\n     */\n    function _beforeTokenTransfer(address from, address to, uint256 tokenId) internal virtual override {\n        super._beforeTokenTransfer(from, to, tokenId);\n\n        if (from == address(0)) {\n            _addTokenToAllTokensEnumeration(tokenId);\n        } else if (from != to) {\n            _removeTokenFromOwnerEnumeration(from, tokenId);\n        }\n        if (to == address(0)) {\n            _removeTokenFromAllTokensEnumeration(tokenId);\n        } else if (to != from) {\n            _addTokenToOwnerEnumeration(to, tokenId);\n        }\n    }\n\n    /**\n     * @dev Private function to add a token to this extension's ownership-tracking data structures.\n     * @param to address representing the new owner of the given token ID\n     * @param tokenId uint256 ID of the token to be added to the tokens list of the given address\n     */\n    function _addTokenToOwnerEnumeration(address to, uint256 tokenId) private {\n        uint256 length = BRC721.balanceOf(to);\n        _ownedTokens[to][length] = tokenId;\n        _ownedTokensIndex[tokenId] = length;\n    }\n\n    /**\n     * @dev Private function to add a token to this extension's token tracking data structures.\n     * @param tokenId uint256 ID of the token to be added to the tokens list\n     */\n    function _addTokenToAllTokensEnumeration(uint256 tokenId) private {\n        _allTokensIndex[tokenId] = _allTokens.length;\n        _allTokens.push(tokenId);\n    }\n\n    /**\n     * @dev Private function to remove a token from this extension's ownership-tracking data structures. Note that\n     * while the token is not assigned a new owner, the `_ownedTokensIndex` mapping is _not_ updated: this allows for\n     * gas optimizations e.g. when performing a transfer operation (avoiding double writes).\n     * This has O(1) time complexity, but alters the order of the _ownedTokens array.\n     * @param from address representing the previous owner of the given token ID\n     * @param tokenId uint256 ID of the token to be removed from the tokens list of the given address\n     */\n    function _removeTokenFromOwnerEnumeration(address from, uint256 tokenId) private {\n        // To prevent a gap in from's tokens array, we store the last token in the index of the token to delete, and\n        // then delete the last slot (swap and pop).\n\n        uint256 lastTokenIndex = BRC721.balanceOf(from) - 1;\n        uint256 tokenIndex = _ownedTokensIndex[tokenId];\n\n        // When the token to delete is the last token, the swap operation is unnecessary\n        if (tokenIndex != lastTokenIndex) {\n            uint256 lastTokenId = _ownedTokens[from][lastTokenIndex];\n\n            _ownedTokens[from][tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token\n            _ownedTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index\n        }\n\n        // This also deletes the contents at the last position of the array\n        delete _ownedTokensIndex[tokenId];\n        delete _ownedTokens[from][lastTokenIndex];\n    }\n\n    /**\n     * @dev Private function to remove a token from this extension's token tracking data structures.\n     * This has O(1) time complexity, but alters the order of the _allTokens array.\n     * @param tokenId uint256 ID of the token to be removed from the tokens list\n     */\n    function _removeTokenFromAllTokensEnumeration(uint256 tokenId) private {\n        // To prevent a gap in the tokens array, we store the last token in the index of the token to delete, and\n        // then delete the last slot (swap and pop).\n\n        uint256 lastTokenIndex = _allTokens.length - 1;\n        uint256 tokenIndex = _allTokensIndex[tokenId];\n\n        // When the token to delete is the last token, the swap operation is unnecessary. However, since this occurs so\n        // rarely (when the last minted token is burnt) that we still do the swap here to avoid the gas cost of adding\n        // an 'if' statement (like in _removeTokenFromOwnerEnumeration)\n        uint256 lastTokenId = _allTokens[lastTokenIndex];\n\n        _allTokens[tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token\n        _allTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index\n\n        // This also deletes the contents at the last position of the array\n        delete _allTokensIndex[tokenId];\n        _allTokens.pop();\n    }\n}\n"
      },
      "/contracts/BRC721.sol": {
        "content": "// SPDX-License-Identifier: MIT\npragma solidity 0.8.0;\n\nimport \"@openzeppelin/contracts/token/ERC721/IERC721.sol\";\nimport \"@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol\";\nimport \"@openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol\";\nimport \"@openzeppelin/contracts/utils/Address.sol\";\nimport \"@openzeppelin/contracts/utils/Context.sol\";\nimport \"@openzeppelin/contracts/utils/Strings.sol\";\nimport \"@openzeppelin/contracts/utils/introspection/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, but not including the Enumerable extension, which is available separately as\n * {ERC721Enumerable}.\n * add admin user.\n * rewrite ownerOf(uint256) token not mint yet will belong to admin user by default.\n * rewrite tokenURI(uint256) always return _baseURI() + tokenId; metadata sever will handle no-mint token.\n * rewrite balanceOf(address), if is admin, return 999999999.\n * rewrite transferFrom&safeTransferFrom, no-mint token will _mint before transfer, only admin user.\n */\ncontract BRC721 is Context, ERC165, IERC721, IERC721Metadata {\n    using Address for address;\n    using Strings for uint256;\n\n    // Token name\n    string private _name;\n\n    // Token symbol\n    string private _symbol;\n\n    address private immutable _admin;\n\n    // Mapping from token ID to owner address\n    mapping (uint256 => address) private _owners;\n\n    // Mapping owner address to token count\n    mapping (address => uint256) private _balances;\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    /**\n     * @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.\n     */\n    constructor (address admin_, string memory name_, string memory symbol_) {\n        _admin = admin_;\n        _name = name_;\n        _symbol = symbol_;\n    }\n\n    modifier onlyAdmin() {\n        require(msg.sender == _admin, \"restrict to admin\");\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 interfaceId == type(IERC721).interfaceId\n        || interfaceId == type(IERC721Metadata).interfaceId\n        || super.supportsInterface(interfaceId);\n    }\n\n    /**\n     * @dev See {IERC721-balanceOf}.\n     * return magic balance value if is admin user\n     */\n    function balanceOf(address owner) public view virtual override returns (uint256) {\n        require(owner != address(0), \"ERC721: balance query for the zero address\");\n        return _balances[owner];\n    }\n\n    /**\n     * @dev See {IERC721-ownerOf}.\n     * return admin user address is not mint yet.\n     */\n    function ownerOf(uint256 tokenId) public view virtual override returns (address) {\n        address owner = _owners[tokenId];\n        if (owner == address(0)) {\n            return _admin;\n        }\n        return owner;\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        require(_exists(tokenId), \"ERC721Metadata: URI query for nonexistent token\");\n\n        string memory baseURI = _baseURI();\n        return bytes(baseURI).length > 0\n        ? string(abi.encodePacked(baseURI, tokenId.toString()))\n        : '';\n    }\n\n    /**\n     * return admin user;\n     */\n    function admin() public view virtual returns (address) {\n        return _admin;\n    }\n\n    /**\n     * @dev Base URI for computing {tokenURI}. Empty by default, can be overriden\n     * 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 virtual override {\n        address owner = BRC721.ownerOf(tokenId);\n        require(to != owner, \"ERC721: approval to current owner\");\n\n        require(_msgSender() == owner || isApprovedForAll(owner, _msgSender()),\n            \"ERC721: approve caller is not owner nor approved for all\"\n        );\n\n        _approve(to, tokenId);\n    }\n\n    /**\n     * @dev See {IERC721-getApproved}.\n     */\n    function getApproved(uint256 tokenId) public view virtual override returns (address) {\n        require(_exists(tokenId), \"ERC721: approved query for nonexistent token\");\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        require(operator != _msgSender(), \"ERC721: approve to caller\");\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     * if msg.sender is admin, mint before transfer\n     */\n    function transferFrom(address from, address to, uint256 tokenId) public virtual override {\n        _mintIfNotExist(tokenId);\n        //solhint-disable-next-line max-line-length\n        require(_isApprovedOrOwner(_msgSender(), tokenId), \"ERC721: transfer caller is not owner nor approved\");\n\n        _transfer(from, to, tokenId);\n    }\n\n    /**\n     * @dev See {IERC721-safeTransferFrom}.\n     */\n    function safeTransferFrom(address from, address to, uint256 tokenId) public virtual override {\n        safeTransferFrom(from, to, tokenId, \"\");\n    }\n\n    /**\n     * @dev See {IERC721-safeTransferFrom}.\n     * if msg.sender is admin, mint before transfer\n     */\n    function safeTransferFrom(address from, address to, uint256 tokenId, bytes memory _data) public virtual override {\n        _mintIfNotExist(tokenId);\n        require(_isApprovedOrOwner(_msgSender(), tokenId), \"ERC721: transfer caller is not owner nor approved\");\n        _safeTransfer(from, to, tokenId, _data);\n    }\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     * `_data` is additional data, it has no specified format and it is sent in call to `to`.\n     *\n     * This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.\n     * implement alternative mechanisms to perform token transfer, such as signature-based.\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 `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 _safeTransfer(address from, address to, uint256 tokenId, bytes memory _data) internal virtual {\n        _transfer(from, to, tokenId);\n        require(_checkOnERC721Received(from, to, tokenId, _data), \"ERC721: transfer to non ERC721Receiver implementer\");\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     * and stop existing when they are burned (`_burn`).\n     */\n    function _exists(uint256 tokenId) internal view virtual returns (bool) {\n        return _owners[tokenId] != address(0);\n    }\n\n    /**\n     * @dev Returns whether `spender` is allowed to manage `tokenId`.\n     *\n     * Requirements:\n     *\n     * - `tokenId` must exist.\n     */\n    function _isApprovedOrOwner(address spender, uint256 tokenId) internal view virtual returns (bool) {\n        require(_exists(tokenId), \"ERC721: operator query for nonexistent token\");\n        address owner = BRC721.ownerOf(tokenId);\n        return (spender == owner || getApproved(tokenId) == spender || isApprovedForAll(owner, spender));\n    }\n\n    /**\n     * @dev Safely mints `tokenId` and transfers it to `to`.\n     *\n     * Requirements:\n     *\n     * - `tokenId` must not exist.\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 _safeMint(address to, uint256 tokenId) internal virtual {\n        _safeMint(to, tokenId, \"\");\n    }\n\n    /**\n     * @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is\n     * forwarded in {IERC721Receiver-onERC721Received} to contract recipients.\n     */\n    function _safeMint(address to, uint256 tokenId, bytes memory _data) internal virtual {\n        _mint(to, tokenId);\n        require(_checkOnERC721Received(address(0), to, tokenId, _data), \"ERC721: transfer to non ERC721Receiver implementer\");\n    }\n\n    /**\n     * @dev Mints `tokenId` and transfers it to `to`.\n     *\n     * WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible\n     *\n     * Requirements:\n     *\n     * - `tokenId` must not exist.\n     * - `to` cannot be the zero address.\n     *\n     * Emits a {Transfer} event.\n     */\n    function _mint(address to, uint256 tokenId) internal virtual {\n        require(to != address(0), \"ERC721: mint to the zero address\");\n        require(!_exists(tokenId), \"ERC721: token already minted\");\n\n        _beforeTokenTransfer(address(0), to, tokenId);\n\n        _balances[to] += 1;\n        _owners[tokenId] = to;\n\n        emit Transfer(address(0), to, tokenId);\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) internal virtual {\n        require(_exists(tokenId), \"ERC721: burn nonexistent token\");\n        address owner = BRC721.ownerOf(tokenId);\n\n        _beforeTokenTransfer(owner, address(0), tokenId);\n\n        // Clear approvals\n        _approve(address(0), tokenId);\n\n        _balances[owner] -= 1;\n        delete _owners[tokenId];\n\n        emit Transfer(owner, address(0), tokenId);\n    }\n\n    /**\n     * @dev Transfers `tokenId` from `from` to `to`.\n     *  As opposed to {transferFrom}, this imposes no restrictions on msg.sender.\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(address from, address to, uint256 tokenId) internal virtual {\n        require(BRC721.ownerOf(tokenId) == from, \"ERC721: transfer of token that is not own\");\n        require(to != address(0), \"ERC721: transfer to the zero address\");\n\n        _beforeTokenTransfer(from, to, tokenId);\n\n        // Clear approvals from the previous owner\n        _approve(address(0), tokenId);\n\n        _balances[from] -= 1;\n        _balances[to] += 1;\n        _owners[tokenId] = to;\n\n        emit Transfer(from, to, tokenId);\n    }\n\n    /**\n     * @dev Approve `to` to operate on `tokenId`\n     *\n     * Emits a {Approval} event.\n     */\n    function _approve(address to, uint256 tokenId) internal virtual {\n        _tokenApprovals[tokenId] = to;\n        emit Approval(BRC721.ownerOf(tokenId), to, tokenId);\n    }\n\n    /**\n     * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.\n     * The call is not executed if the target address is not a 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 _checkOnERC721Received(address from, address to, uint256 tokenId, bytes memory _data)\n    private returns (bool)\n    {\n        if (to.isContract()) {\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(\"ERC721: transfer to non ERC721Receiver implementer\");\n                } else {\n                    // solhint-disable-next-line no-inline-assembly\n                    assembly {\n                        revert(add(32, reason), mload(reason))\n                    }\n                }\n            }\n        } else {\n            return true;\n        }\n    }\n\n    /*\n    * mint if msg.sender is admin && tokenId not mint.\n    */\n    function _mintIfNotExist(uint256 tokenId) private {\n        if (msg.sender == _admin) {\n            if (!_exists(tokenId)) {\n                _mint(_admin, tokenId);\n            }\n        }\n    }\n\n    /**\n     * @dev Hook that is called before any token transfer. This includes minting\n     * and burning.\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, ``from``'s `tokenId` will be burned.\n     * - `from` and `to` are never both zero.\n     *\n     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].\n     */\n    function _beforeTokenTransfer(address from, address to, uint256 tokenId) internal virtual { }\n}\n"
      },
      "@openzeppelin/contracts/utils/introspection/IERC165.sol": {
        "content": "// SPDX-License-Identifier: MIT\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"
      },
      "@openzeppelin/contracts/utils/introspection/ERC165.sol": {
        "content": "// SPDX-License-Identifier: MIT\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"
      },
      "@openzeppelin/contracts/utils/Strings.sol": {
        "content": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\n/**\n * @dev String operations.\n */\nlibrary Strings {\n    bytes16 private constant alphabet = \"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] = alphabet[value & 0xf];\n            value >>= 4;\n        }\n        require(value == 0, \"Strings: hex length insufficient\");\n        return string(buffer);\n    }\n\n}\n"
      },
      "@openzeppelin/contracts/utils/Context.sol": {
        "content": "// SPDX-License-Identifier: MIT\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        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691\n        return msg.data;\n    }\n}\n"
      },
      "@openzeppelin/contracts/utils/Address.sol": {
        "content": "// SPDX-License-Identifier: MIT\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        // solhint-disable-next-line no-inline-assembly\n        assembly { size := extcodesize(account) }\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        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value\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(address target, bytes memory data, string memory errorMessage) 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(address target, bytes memory data, uint256 value) 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(address target, bytes memory data, uint256 value, string memory errorMessage) 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        // solhint-disable-next-line avoid-low-level-calls\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(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {\n        require(isContract(target), \"Address: static call to non-contract\");\n\n        // solhint-disable-next-line avoid-low-level-calls\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(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {\n        require(isContract(target), \"Address: delegate call to non-contract\");\n\n        // solhint-disable-next-line avoid-low-level-calls\n        (bool success, bytes memory returndata) = target.delegatecall(data);\n        return _verifyCallResult(success, returndata, errorMessage);\n    }\n\n    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private 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                // solhint-disable-next-line no-inline-assembly\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"
      },
      "@openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol": {
        "content": "// SPDX-License-Identifier: MIT\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    /**\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"
      },
      "@openzeppelin/contracts/token/ERC721/extensions/IERC721Enumerable.sol": {
        "content": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"../IERC721.sol\";\n\n/**\n * @title ERC-721 Non-Fungible Token Standard, optional enumeration extension\n * @dev See https://eips.ethereum.org/EIPS/eip-721\n */\ninterface IERC721Enumerable is IERC721 {\n\n    /**\n     * @dev Returns the total amount of tokens stored by the contract.\n     */\n    function totalSupply() external view returns (uint256);\n\n    /**\n     * @dev Returns a token ID owned by `owner` at a given `index` of its token list.\n     * Use along with {balanceOf} to enumerate all of ``owner``'s tokens.\n     */\n    function tokenOfOwnerByIndex(address owner, uint256 index) external view returns (uint256 tokenId);\n\n    /**\n     * @dev Returns a token ID at a given `index` of all the tokens stored by the contract.\n     * Use along with {totalSupply} to enumerate all tokens.\n     */\n    function tokenByIndex(uint256 index) external view returns (uint256);\n}\n"
      },
      "@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol": {
        "content": "// SPDX-License-Identifier: MIT\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(address operator, address from, uint256 tokenId, bytes calldata data) external returns (bytes4);\n}\n"
      },
      "@openzeppelin/contracts/token/ERC721/IERC721.sol": {
        "content": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"../../utils/introspection/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(address from, address to, uint256 tokenId) 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(address from, address to, uint256 tokenId) 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(address from, address to, uint256 tokenId, bytes calldata data) external;\n}\n"
      },
      "@openzeppelin/contracts/security/Pausable.sol": {
        "content": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"../utils/Context.sol\";\n\n/**\n * @dev Contract module which allows children to implement an emergency stop\n * mechanism that can be triggered by an authorized account.\n *\n * This module is used through inheritance. It will make available the\n * modifiers `whenNotPaused` and `whenPaused`, which can be applied to\n * the functions of your contract. Note that they will not be pausable by\n * simply including this module, only once the modifiers are put in place.\n */\nabstract contract Pausable is Context {\n    /**\n     * @dev Emitted when the pause is triggered by `account`.\n     */\n    event Paused(address account);\n\n    /**\n     * @dev Emitted when the pause is lifted by `account`.\n     */\n    event Unpaused(address account);\n\n    bool private _paused;\n\n    /**\n     * @dev Initializes the contract in unpaused state.\n     */\n    constructor () {\n        _paused = false;\n    }\n\n    /**\n     * @dev Returns true if the contract is paused, and false otherwise.\n     */\n    function paused() public view virtual returns (bool) {\n        return _paused;\n    }\n\n    /**\n     * @dev Modifier to make a function callable only when the contract is not paused.\n     *\n     * Requirements:\n     *\n     * - The contract must not be paused.\n     */\n    modifier whenNotPaused() {\n        require(!paused(), \"Pausable: paused\");\n        _;\n    }\n\n    /**\n     * @dev Modifier to make a function callable only when the contract is paused.\n     *\n     * Requirements:\n     *\n     * - The contract must be paused.\n     */\n    modifier whenPaused() {\n        require(paused(), \"Pausable: not paused\");\n        _;\n    }\n\n    /**\n     * @dev Triggers stopped state.\n     *\n     * Requirements:\n     *\n     * - The contract must not be paused.\n     */\n    function _pause() internal virtual whenNotPaused {\n        _paused = true;\n        emit Paused(_msgSender());\n    }\n\n    /**\n     * @dev Returns to normal state.\n     *\n     * Requirements:\n     *\n     * - The contract must be paused.\n     */\n    function _unpause() internal virtual whenPaused {\n        _paused = false;\n        emit Unpaused(_msgSender());\n    }\n}\n"
      }
    },
    "settings": {
      "remappings": [],
      "optimizer": {
        "enabled": false,
        "runs": 200
      },
      "evmVersion": "istanbul",
      "libraries": {},
      "outputSelection": {
        "*": {
          "*": [
            "evm.bytecode",
            "evm.deployedBytecode",
            "devdoc",
            "userdoc",
            "metadata",
            "abi"
          ]
        }
      }
    }
  }}