// Sources flattened with hardhat v2.8.4 https://hardhat.org // File @openzeppelin/contracts/utils/introspection/IERC165.sol@v4.5.0 // SPDX-License-Identifier: MIT // OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol) pragma solidity ^0.8.0; /** * @dev Interface of the ERC165 standard, as defined in the * https://eips.ethereum.org/EIPS/eip-165[EIP]. * * Implementers can declare support of contract interfaces, which can then be * queried by others ({ERC165Checker}). * * For an implementation, see {ERC165}. */ interface IERC165 { /** * @dev Returns true if this contract implements the interface defined by * `interfaceId`. See the corresponding * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section] * to learn more about how these ids are created. * * This function call must use less than 30 000 gas. */ function supportsInterface(bytes4 interfaceId) external view returns (bool); } // File @openzeppelin/contracts/token/ERC721/IERC721.sol@v4.5.0 // OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721.sol) pragma solidity ^0.8.0; /** * @dev Required interface of an ERC721 compliant contract. */ interface IERC721 is IERC165 { /** * @dev Emitted when `tokenId` token is transferred from `from` to `to`. */ event Transfer(address indexed from, address indexed to, uint256 indexed tokenId); /** * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token. */ event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId); /** * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets. */ event ApprovalForAll(address indexed owner, address indexed operator, bool approved); /** * @dev Returns the number of tokens in ``owner``'s account. */ function balanceOf(address owner) external view returns (uint256 balance); /** * @dev Returns the owner of the `tokenId` token. * * Requirements: * * - `tokenId` must exist. */ function ownerOf(uint256 tokenId) external view returns (address owner); /** * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients * are aware of the ERC721 protocol to prevent tokens from being forever locked. * * Requirements: * * - `from` cannot be the zero address. * - `to` cannot be the zero address. * - `tokenId` token must exist and be owned by `from`. * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}. * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer. * * Emits a {Transfer} event. */ function safeTransferFrom( address from, address to, uint256 tokenId ) external; /** * @dev Transfers `tokenId` token from `from` to `to`. * * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible. * * Requirements: * * - `from` cannot be the zero address. * - `to` cannot be the zero address. * - `tokenId` token must be owned by `from`. * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}. * * Emits a {Transfer} event. */ function transferFrom( address from, address to, uint256 tokenId ) external; /** * @dev Gives permission to `to` to transfer `tokenId` token to another account. * The approval is cleared when the token is transferred. * * Only a single account can be approved at a time, so approving the zero address clears previous approvals. * * Requirements: * * - The caller must own the token or be an approved operator. * - `tokenId` must exist. * * Emits an {Approval} event. */ function approve(address to, uint256 tokenId) external; /** * @dev Returns the account approved for `tokenId` token. * * Requirements: * * - `tokenId` must exist. */ function getApproved(uint256 tokenId) external view returns (address operator); /** * @dev Approve or remove `operator` as an operator for the caller. * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller. * * Requirements: * * - The `operator` cannot be the caller. * * Emits an {ApprovalForAll} event. */ function setApprovalForAll(address operator, bool _approved) external; /** * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`. * * See {setApprovalForAll} */ function isApprovedForAll(address owner, address operator) external view returns (bool); /** * @dev Safely transfers `tokenId` token from `from` to `to`. * * Requirements: * * - `from` cannot be the zero address. * - `to` cannot be the zero address. * - `tokenId` token must exist and be owned by `from`. * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}. * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer. * * Emits a {Transfer} event. */ function safeTransferFrom( address from, address to, uint256 tokenId, bytes calldata data ) external; } // File @openzeppelin/contracts/token/ERC721/IERC721Receiver.sol@v4.5.0 // OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721Receiver.sol) pragma solidity ^0.8.0; /** * @title ERC721 token receiver interface * @dev Interface for any contract that wants to support safeTransfers * from ERC721 asset contracts. */ interface IERC721Receiver { /** * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom} * by `operator` from `from`, this function is called. * * It must return its Solidity selector to confirm the token transfer. * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted. * * The selector can be obtained in Solidity with `IERC721.onERC721Received.selector`. */ function onERC721Received( address operator, address from, uint256 tokenId, bytes calldata data ) external returns (bytes4); } // File @openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol@v4.5.0 // OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/IERC721Metadata.sol) pragma solidity ^0.8.0; /** * @title ERC-721 Non-Fungible Token Standard, optional metadata extension * @dev See https://eips.ethereum.org/EIPS/eip-721 */ interface IERC721Metadata is IERC721 { /** * @dev Returns the token collection name. */ function name() external view returns (string memory); /** * @dev Returns the token collection symbol. */ function symbol() external view returns (string memory); /** * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token. */ function tokenURI(uint256 tokenId) external view returns (string memory); } // File @openzeppelin/contracts/utils/Address.sol@v4.5.0 // OpenZeppelin Contracts (last updated v4.5.0) (utils/Address.sol) pragma solidity ^0.8.1; /** * @dev Collection of functions related to the address type */ library Address { /** * @dev Returns true if `account` is a contract. * * [IMPORTANT] * ==== * It is unsafe to assume that an address for which this function returns * false is an externally-owned account (EOA) and not a contract. * * Among others, `isContract` will return false for the following * types of addresses: * * - an externally-owned account * - a contract in construction * - an address where a contract will be created * - an address where a contract lived, but was destroyed * ==== * * [IMPORTANT] * ==== * You shouldn't rely on `isContract` to protect against flash loan attacks! * * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract * constructor. * ==== */ function isContract(address account) internal view returns (bool) { // This method relies on extcodesize/address.code.length, which returns 0 // for contracts in construction, since the code is only stored at the end // of the constructor execution. return account.code.length > 0; } /** * @dev Replacement for Solidity's `transfer`: sends `amount` wei to * `recipient`, forwarding all available gas and reverting on errors. * * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost * of certain opcodes, possibly making contracts go over the 2300 gas limit * imposed by `transfer`, making them unable to receive funds via * `transfer`. {sendValue} removes this limitation. * * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more]. * * IMPORTANT: because control is transferred to `recipient`, care must be * taken to not create reentrancy vulnerabilities. Consider using * {ReentrancyGuard} or the * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern]. */ function sendValue(address payable recipient, uint256 amount) internal { require(address(this).balance >= amount, "Address: insufficient balance"); (bool success, ) = recipient.call{value: amount}(""); require(success, "Address: unable to send value, recipient may have reverted"); } /** * @dev Performs a Solidity function call using a low level `call`. A * plain `call` is an unsafe replacement for a function call: use this * function instead. * * If `target` reverts with a revert reason, it is bubbled up by this * function (like regular Solidity function calls). * * Returns the raw returned data. To convert to the expected return value, * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`]. * * Requirements: * * - `target` must be a contract. * - calling `target` with `data` must not revert. * * _Available since v3.1._ */ function functionCall(address target, bytes memory data) internal returns (bytes memory) { return functionCall(target, data, "Address: low-level call failed"); } /** * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with * `errorMessage` as a fallback revert reason when `target` reverts. * * _Available since v3.1._ */ function functionCall( address target, bytes memory data, string memory errorMessage ) internal returns (bytes memory) { return functionCallWithValue(target, data, 0, errorMessage); } /** * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], * but also transferring `value` wei to `target`. * * Requirements: * * - the calling contract must have an ETH balance of at least `value`. * - the called Solidity function must be `payable`. * * _Available since v3.1._ */ function functionCallWithValue( address target, bytes memory data, uint256 value ) internal returns (bytes memory) { return functionCallWithValue(target, data, value, "Address: low-level call with value failed"); } /** * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but * with `errorMessage` as a fallback revert reason when `target` reverts. * * _Available since v3.1._ */ function functionCallWithValue( address target, bytes memory data, uint256 value, string memory errorMessage ) internal returns (bytes memory) { require(address(this).balance >= value, "Address: insufficient balance for call"); require(isContract(target), "Address: call to non-contract"); (bool success, bytes memory returndata) = target.call{value: value}(data); return verifyCallResult(success, returndata, errorMessage); } /** * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], * but performing a static call. * * _Available since v3.3._ */ function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) { return functionStaticCall(target, data, "Address: low-level static call failed"); } /** * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`], * but performing a static call. * * _Available since v3.3._ */ function functionStaticCall( address target, bytes memory data, string memory errorMessage ) internal view returns (bytes memory) { require(isContract(target), "Address: static call to non-contract"); (bool success, bytes memory returndata) = target.staticcall(data); return verifyCallResult(success, returndata, errorMessage); } /** * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], * but performing a delegate call. * * _Available since v3.4._ */ function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) { return functionDelegateCall(target, data, "Address: low-level delegate call failed"); } /** * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`], * but performing a delegate call. * * _Available since v3.4._ */ function functionDelegateCall( address target, bytes memory data, string memory errorMessage ) internal returns (bytes memory) { require(isContract(target), "Address: delegate call to non-contract"); (bool success, bytes memory returndata) = target.delegatecall(data); return verifyCallResult(success, returndata, errorMessage); } /** * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the * revert reason using the provided one. * * _Available since v4.3._ */ function verifyCallResult( bool success, bytes memory returndata, string memory errorMessage ) internal pure returns (bytes memory) { if (success) { return returndata; } else { // Look for revert reason and bubble it up if present if (returndata.length > 0) { // The easiest way to bubble the revert reason is using memory via assembly assembly { let returndata_size := mload(returndata) revert(add(32, returndata), returndata_size) } } else { revert(errorMessage); } } } } // File @openzeppelin/contracts/utils/Context.sol@v4.5.0 // OpenZeppelin Contracts v4.4.1 (utils/Context.sol) pragma solidity ^0.8.0; /** * @dev Provides information about the current execution context, including the * sender of the transaction and its data. While these are generally available * via msg.sender and msg.data, they should not be accessed in such a direct * manner, since when dealing with meta-transactions the account sending and * paying for execution may not be the actual sender (as far as an application * is concerned). * * This contract is only required for intermediate, library-like contracts. */ abstract contract Context { function _msgSender() internal view virtual returns (address) { return msg.sender; } function _msgData() internal view virtual returns (bytes calldata) { return msg.data; } } // File @openzeppelin/contracts/utils/Strings.sol@v4.5.0 // OpenZeppelin Contracts v4.4.1 (utils/Strings.sol) pragma solidity ^0.8.0; /** * @dev String operations. */ library Strings { bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef"; /** * @dev Converts a `uint256` to its ASCII `string` decimal representation. */ function toString(uint256 value) internal pure returns (string memory) { // Inspired by OraclizeAPI's implementation - MIT licence // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol if (value == 0) { return "0"; } uint256 temp = value; uint256 digits; while (temp != 0) { digits++; temp /= 10; } bytes memory buffer = new bytes(digits); while (value != 0) { digits -= 1; buffer[digits] = bytes1(uint8(48 + uint256(value % 10))); value /= 10; } return string(buffer); } /** * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation. */ function toHexString(uint256 value) internal pure returns (string memory) { if (value == 0) { return "0x00"; } uint256 temp = value; uint256 length = 0; while (temp != 0) { length++; temp >>= 8; } return toHexString(value, length); } /** * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length. */ function toHexString(uint256 value, uint256 length) internal pure returns (string memory) { bytes memory buffer = new bytes(2 * length + 2); buffer[0] = "0"; buffer[1] = "x"; for (uint256 i = 2 * length + 1; i > 1; --i) { buffer[i] = _HEX_SYMBOLS[value & 0xf]; value >>= 4; } require(value == 0, "Strings: hex length insufficient"); return string(buffer); } } // File @openzeppelin/contracts/utils/introspection/ERC165.sol@v4.5.0 // OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol) pragma solidity ^0.8.0; /** * @dev Implementation of the {IERC165} interface. * * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check * for the additional interface id that will be supported. For example: * * ```solidity * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) { * return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId); * } * ``` * * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation. */ abstract contract ERC165 is IERC165 { /** * @dev See {IERC165-supportsInterface}. */ function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) { return interfaceId == type(IERC165).interfaceId; } } // File @openzeppelin/contracts/token/ERC721/ERC721.sol@v4.5.0 // OpenZeppelin Contracts (last updated v4.5.0) (token/ERC721/ERC721.sol) pragma solidity ^0.8.0; /** * @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including * the Metadata extension, but not including the Enumerable extension, which is available separately as * {ERC721Enumerable}. */ contract ERC721 is Context, ERC165, IERC721, IERC721Metadata { using Address for address; using Strings for uint256; // Token name string private _name; // Token symbol string private _symbol; // Mapping from token ID to owner address mapping(uint256 => address) private _owners; // Mapping owner address to token count mapping(address => uint256) private _balances; // Mapping from token ID to approved address mapping(uint256 => address) private _tokenApprovals; // Mapping from owner to operator approvals mapping(address => mapping(address => bool)) private _operatorApprovals; /** * @dev Initializes the contract by setting a `name` and a `symbol` to the token collection. */ constructor(string memory name_, string memory symbol_) { _name = name_; _symbol = symbol_; } /** * @dev See {IERC165-supportsInterface}. */ function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) { return interfaceId == type(IERC721).interfaceId || interfaceId == type(IERC721Metadata).interfaceId || super.supportsInterface(interfaceId); } /** * @dev See {IERC721-balanceOf}. */ function balanceOf(address owner) public view virtual override returns (uint256) { require(owner != address(0), "ERC721: balance query for the zero address"); return _balances[owner]; } /** * @dev See {IERC721-ownerOf}. */ function ownerOf(uint256 tokenId) public view virtual override returns (address) { address owner = _owners[tokenId]; require(owner != address(0), "ERC721: owner query for nonexistent token"); return owner; } /** * @dev See {IERC721Metadata-name}. */ function name() public view virtual override returns (string memory) { return _name; } /** * @dev See {IERC721Metadata-symbol}. */ function symbol() public view virtual override returns (string memory) { return _symbol; } /** * @dev See {IERC721Metadata-tokenURI}. */ function tokenURI(uint256 tokenId) public view virtual override returns (string memory) { require(_exists(tokenId), "ERC721Metadata: URI query for nonexistent token"); string memory baseURI = _baseURI(); return bytes(baseURI).length > 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : ""; } /** * @dev Base URI for computing {tokenURI}. If set, the resulting URI for each * token will be the concatenation of the `baseURI` and the `tokenId`. Empty * by default, can be overriden in child contracts. */ function _baseURI() internal view virtual returns (string memory) { return ""; } /** * @dev See {IERC721-approve}. */ function approve(address to, uint256 tokenId) public virtual override { address owner = ERC721.ownerOf(tokenId); require(to != owner, "ERC721: approval to current owner"); require( _msgSender() == owner || isApprovedForAll(owner, _msgSender()), "ERC721: approve caller is not owner nor approved for all" ); _approve(to, tokenId); } /** * @dev See {IERC721-getApproved}. */ function getApproved(uint256 tokenId) public view virtual override returns (address) { require(_exists(tokenId), "ERC721: approved query for nonexistent token"); return _tokenApprovals[tokenId]; } /** * @dev See {IERC721-setApprovalForAll}. */ function setApprovalForAll(address operator, bool approved) public virtual override { _setApprovalForAll(_msgSender(), operator, approved); } /** * @dev See {IERC721-isApprovedForAll}. */ function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) { return _operatorApprovals[owner][operator]; } /** * @dev See {IERC721-transferFrom}. */ function transferFrom( address from, address to, uint256 tokenId ) public virtual override { //solhint-disable-next-line max-line-length require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved"); _transfer(from, to, tokenId); } /** * @dev See {IERC721-safeTransferFrom}. */ function safeTransferFrom( address from, address to, uint256 tokenId ) public virtual override { safeTransferFrom(from, to, tokenId, ""); } /** * @dev See {IERC721-safeTransferFrom}. */ function safeTransferFrom( address from, address to, uint256 tokenId, bytes memory _data ) public virtual override { require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved"); _safeTransfer(from, to, tokenId, _data); } /** * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients * are aware of the ERC721 protocol to prevent tokens from being forever locked. * * `_data` is additional data, it has no specified format and it is sent in call to `to`. * * This internal function is equivalent to {safeTransferFrom}, and can be used to e.g. * implement alternative mechanisms to perform token transfer, such as signature-based. * * Requirements: * * - `from` cannot be the zero address. * - `to` cannot be the zero address. * - `tokenId` token must exist and be owned by `from`. * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer. * * Emits a {Transfer} event. */ function _safeTransfer( address from, address to, uint256 tokenId, bytes memory _data ) internal virtual { _transfer(from, to, tokenId); require(_checkOnERC721Received(from, to, tokenId, _data), "ERC721: transfer to non ERC721Receiver implementer"); } /** * @dev Returns whether `tokenId` exists. * * Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}. * * Tokens start existing when they are minted (`_mint`), * and stop existing when they are burned (`_burn`). */ function _exists(uint256 tokenId) internal view virtual returns (bool) { return _owners[tokenId] != address(0); } /** * @dev Returns whether `spender` is allowed to manage `tokenId`. * * Requirements: * * - `tokenId` must exist. */ function _isApprovedOrOwner(address spender, uint256 tokenId) internal view virtual returns (bool) { require(_exists(tokenId), "ERC721: operator query for nonexistent token"); address owner = ERC721.ownerOf(tokenId); return (spender == owner || getApproved(tokenId) == spender || isApprovedForAll(owner, spender)); } /** * @dev Safely mints `tokenId` and transfers it to `to`. * * Requirements: * * - `tokenId` must not exist. * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer. * * Emits a {Transfer} event. */ function _safeMint(address to, uint256 tokenId) internal virtual { _safeMint(to, tokenId, ""); } /** * @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is * forwarded in {IERC721Receiver-onERC721Received} to contract recipients. */ function _safeMint( address to, uint256 tokenId, bytes memory _data ) internal virtual { _mint(to, tokenId); require( _checkOnERC721Received(address(0), to, tokenId, _data), "ERC721: transfer to non ERC721Receiver implementer" ); } /** * @dev Mints `tokenId` and transfers it to `to`. * * WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible * * Requirements: * * - `tokenId` must not exist. * - `to` cannot be the zero address. * * Emits a {Transfer} event. */ function _mint(address to, uint256 tokenId) internal virtual { require(to != address(0), "ERC721: mint to the zero address"); require(!_exists(tokenId), "ERC721: token already minted"); _beforeTokenTransfer(address(0), to, tokenId); _balances[to] += 1; _owners[tokenId] = to; emit Transfer(address(0), to, tokenId); _afterTokenTransfer(address(0), to, tokenId); } /** * @dev Destroys `tokenId`. * The approval is cleared when the token is burned. * * Requirements: * * - `tokenId` must exist. * * Emits a {Transfer} event. */ function _burn(uint256 tokenId) internal virtual { address owner = ERC721.ownerOf(tokenId); _beforeTokenTransfer(owner, address(0), tokenId); // Clear approvals _approve(address(0), tokenId); _balances[owner] -= 1; delete _owners[tokenId]; emit Transfer(owner, address(0), tokenId); _afterTokenTransfer(owner, address(0), tokenId); } /** * @dev Transfers `tokenId` from `from` to `to`. * As opposed to {transferFrom}, this imposes no restrictions on msg.sender. * * Requirements: * * - `to` cannot be the zero address. * - `tokenId` token must be owned by `from`. * * Emits a {Transfer} event. */ function _transfer( address from, address to, uint256 tokenId ) internal virtual { require(ERC721.ownerOf(tokenId) == from, "ERC721: transfer from incorrect owner"); require(to != address(0), "ERC721: transfer to the zero address"); _beforeTokenTransfer(from, to, tokenId); // Clear approvals from the previous owner _approve(address(0), tokenId); _balances[from] -= 1; _balances[to] += 1; _owners[tokenId] = to; emit Transfer(from, to, tokenId); _afterTokenTransfer(from, to, tokenId); } /** * @dev Approve `to` to operate on `tokenId` * * Emits a {Approval} event. */ function _approve(address to, uint256 tokenId) internal virtual { _tokenApprovals[tokenId] = to; emit Approval(ERC721.ownerOf(tokenId), to, tokenId); } /** * @dev Approve `operator` to operate on all of `owner` tokens * * Emits a {ApprovalForAll} event. */ function _setApprovalForAll( address owner, address operator, bool approved ) internal virtual { require(owner != operator, "ERC721: approve to caller"); _operatorApprovals[owner][operator] = approved; emit ApprovalForAll(owner, operator, approved); } /** * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address. * The call is not executed if the target address is not a contract. * * @param from address representing the previous owner of the given token ID * @param to target address that will receive the tokens * @param tokenId uint256 ID of the token to be transferred * @param _data bytes optional data to send along with the call * @return bool whether the call correctly returned the expected magic value */ function _checkOnERC721Received( address from, address to, uint256 tokenId, bytes memory _data ) private returns (bool) { if (to.isContract()) { try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, _data) returns (bytes4 retval) { return retval == IERC721Receiver.onERC721Received.selector; } catch (bytes memory reason) { if (reason.length == 0) { revert("ERC721: transfer to non ERC721Receiver implementer"); } else { assembly { revert(add(32, reason), mload(reason)) } } } } else { return true; } } /** * @dev Hook that is called before any token transfer. This includes minting * and burning. * * Calling conditions: * * - When `from` and `to` are both non-zero, ``from``'s `tokenId` will be * transferred to `to`. * - When `from` is zero, `tokenId` will be minted for `to`. * - When `to` is zero, ``from``'s `tokenId` will be burned. * - `from` and `to` are never both zero. * * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks]. */ function _beforeTokenTransfer( address from, address to, uint256 tokenId ) internal virtual {} /** * @dev Hook that is called after any transfer of tokens. This includes * minting and burning. * * Calling conditions: * * - when `from` and `to` are both non-zero. * - `from` and `to` are never both zero. * * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks]. */ function _afterTokenTransfer( address from, address to, uint256 tokenId ) internal virtual {} } // File @openzeppelin/contracts/access/Ownable.sol@v4.5.0 // OpenZeppelin Contracts v4.4.1 (access/Ownable.sol) pragma solidity ^0.8.0; /** * @dev Contract module which provides a basic access control mechanism, where * there is an account (an owner) that can be granted exclusive access to * specific functions. * * By default, the owner account will be the one that deploys the contract. This * can later be changed with {transferOwnership}. * * This module is used through inheritance. It will make available the modifier * `onlyOwner`, which can be applied to your functions to restrict their use to * the owner. */ abstract contract Ownable is Context { address private _owner; event OwnershipTransferred(address indexed previousOwner, address indexed newOwner); /** * @dev Initializes the contract setting the deployer as the initial owner. */ constructor() { _transferOwnership(_msgSender()); } /** * @dev Returns the address of the current owner. */ function owner() public view virtual returns (address) { return _owner; } /** * @dev Throws if called by any account other than the owner. */ modifier onlyOwner() { require(owner() == _msgSender(), "Ownable: caller is not the owner"); _; } /** * @dev Leaves the contract without owner. It will not be possible to call * `onlyOwner` functions anymore. Can only be called by the current owner. * * NOTE: Renouncing ownership will leave the contract without an owner, * thereby removing any functionality that is only available to the owner. */ function renounceOwnership() public virtual onlyOwner { _transferOwnership(address(0)); } /** * @dev Transfers ownership of the contract to a new account (`newOwner`). * Can only be called by the current owner. */ function transferOwnership(address newOwner) public virtual onlyOwner { require(newOwner != address(0), "Ownable: new owner is the zero address"); _transferOwnership(newOwner); } /** * @dev Transfers ownership of the contract to a new account (`newOwner`). * Internal function without access restriction. */ function _transferOwnership(address newOwner) internal virtual { address oldOwner = _owner; _owner = newOwner; emit OwnershipTransferred(oldOwner, newOwner); } } // File @openzeppelin/contracts/token/ERC721/extensions/IERC721Enumerable.sol@v4.5.0 // OpenZeppelin Contracts (last updated v4.5.0) (token/ERC721/extensions/IERC721Enumerable.sol) pragma solidity ^0.8.0; /** * @title ERC-721 Non-Fungible Token Standard, optional enumeration extension * @dev See https://eips.ethereum.org/EIPS/eip-721 */ interface IERC721Enumerable is IERC721 { /** * @dev Returns the total amount of tokens stored by the contract. */ function totalSupply() external view returns (uint256); /** * @dev Returns a token ID owned by `owner` at a given `index` of its token list. * Use along with {balanceOf} to enumerate all of ``owner``'s tokens. */ function tokenOfOwnerByIndex(address owner, uint256 index) external view returns (uint256); /** * @dev Returns a token ID at a given `index` of all the tokens stored by the contract. * Use along with {totalSupply} to enumerate all tokens. */ function tokenByIndex(uint256 index) external view returns (uint256); } // File @openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol@v4.5.0 // OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/ERC721Enumerable.sol) pragma solidity ^0.8.0; /** * @dev This implements an optional extension of {ERC721} defined in the EIP that adds * enumerability of all the token ids in the contract as well as all token ids owned by each * account. */ abstract contract ERC721Enumerable is ERC721, IERC721Enumerable { // Mapping from owner to list of owned token IDs mapping(address => mapping(uint256 => uint256)) private _ownedTokens; // Mapping from token ID to index of the owner tokens list mapping(uint256 => uint256) private _ownedTokensIndex; // Array with all token ids, used for enumeration uint256[] private _allTokens; // Mapping from token id to position in the allTokens array mapping(uint256 => uint256) private _allTokensIndex; /** * @dev See {IERC165-supportsInterface}. */ function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165, ERC721) returns (bool) { return interfaceId == type(IERC721Enumerable).interfaceId || super.supportsInterface(interfaceId); } /** * @dev See {IERC721Enumerable-tokenOfOwnerByIndex}. */ function tokenOfOwnerByIndex(address owner, uint256 index) public view virtual override returns (uint256) { require(index < ERC721.balanceOf(owner), "ERC721Enumerable: owner index out of bounds"); return _ownedTokens[owner][index]; } /** * @dev See {IERC721Enumerable-totalSupply}. */ function totalSupply() public view virtual override returns (uint256) { return _allTokens.length; } /** * @dev See {IERC721Enumerable-tokenByIndex}. */ function tokenByIndex(uint256 index) public view virtual override returns (uint256) { require(index < ERC721Enumerable.totalSupply(), "ERC721Enumerable: global index out of bounds"); return _allTokens[index]; } /** * @dev Hook that is called before any token transfer. This includes minting * and burning. * * Calling conditions: * * - When `from` and `to` are both non-zero, ``from``'s `tokenId` will be * transferred to `to`. * - When `from` is zero, `tokenId` will be minted for `to`. * - When `to` is zero, ``from``'s `tokenId` will be burned. * - `from` cannot be the zero address. * - `to` cannot be the zero address. * * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks]. */ function _beforeTokenTransfer( address from, address to, uint256 tokenId ) internal virtual override { super._beforeTokenTransfer(from, to, tokenId); if (from == address(0)) { _addTokenToAllTokensEnumeration(tokenId); } else if (from != to) { _removeTokenFromOwnerEnumeration(from, tokenId); } if (to == address(0)) { _removeTokenFromAllTokensEnumeration(tokenId); } else if (to != from) { _addTokenToOwnerEnumeration(to, tokenId); } } /** * @dev Private function to add a token to this extension's ownership-tracking data structures. * @param to address representing the new owner of the given token ID * @param tokenId uint256 ID of the token to be added to the tokens list of the given address */ function _addTokenToOwnerEnumeration(address to, uint256 tokenId) private { uint256 length = ERC721.balanceOf(to); _ownedTokens[to][length] = tokenId; _ownedTokensIndex[tokenId] = length; } /** * @dev Private function to add a token to this extension's token tracking data structures. * @param tokenId uint256 ID of the token to be added to the tokens list */ function _addTokenToAllTokensEnumeration(uint256 tokenId) private { _allTokensIndex[tokenId] = _allTokens.length; _allTokens.push(tokenId); } /** * @dev Private function to remove a token from this extension's ownership-tracking data structures. Note that * while the token is not assigned a new owner, the `_ownedTokensIndex` mapping is _not_ updated: this allows for * gas optimizations e.g. when performing a transfer operation (avoiding double writes). * This has O(1) time complexity, but alters the order of the _ownedTokens array. * @param from address representing the previous owner of the given token ID * @param tokenId uint256 ID of the token to be removed from the tokens list of the given address */ function _removeTokenFromOwnerEnumeration(address from, uint256 tokenId) private { // To prevent a gap in from's tokens array, we store the last token in the index of the token to delete, and // then delete the last slot (swap and pop). uint256 lastTokenIndex = ERC721.balanceOf(from) - 1; uint256 tokenIndex = _ownedTokensIndex[tokenId]; // When the token to delete is the last token, the swap operation is unnecessary if (tokenIndex != lastTokenIndex) { uint256 lastTokenId = _ownedTokens[from][lastTokenIndex]; _ownedTokens[from][tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token _ownedTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index } // This also deletes the contents at the last position of the array delete _ownedTokensIndex[tokenId]; delete _ownedTokens[from][lastTokenIndex]; } /** * @dev Private function to remove a token from this extension's token tracking data structures. * This has O(1) time complexity, but alters the order of the _allTokens array. * @param tokenId uint256 ID of the token to be removed from the tokens list */ function _removeTokenFromAllTokensEnumeration(uint256 tokenId) private { // To prevent a gap in the tokens array, we store the last token in the index of the token to delete, and // then delete the last slot (swap and pop). uint256 lastTokenIndex = _allTokens.length - 1; uint256 tokenIndex = _allTokensIndex[tokenId]; // When the token to delete is the last token, the swap operation is unnecessary. However, since this occurs so // rarely (when the last minted token is burnt) that we still do the swap here to avoid the gas cost of adding // an 'if' statement (like in _removeTokenFromOwnerEnumeration) uint256 lastTokenId = _allTokens[lastTokenIndex]; _allTokens[tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token _allTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index // This also deletes the contents at the last position of the array delete _allTokensIndex[tokenId]; _allTokens.pop(); } } // File @openzeppelin/contracts/security/ReentrancyGuard.sol@v4.5.0 // OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol) pragma solidity ^0.8.0; /** * @dev Contract module that helps prevent reentrant calls to a function. * * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier * available, which can be applied to functions to make sure there are no nested * (reentrant) calls to them. * * Note that because there is a single `nonReentrant` guard, functions marked as * `nonReentrant` may not call one another. This can be worked around by making * those functions `private`, and then adding `external` `nonReentrant` entry * points to them. * * TIP: If you would like to learn more about reentrancy and alternative ways * to protect against it, check out our blog post * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul]. */ abstract contract ReentrancyGuard { // Booleans are more expensive than uint256 or any type that takes up a full // word because each write operation emits an extra SLOAD to first read the // slot's contents, replace the bits taken up by the boolean, and then write // back. This is the compiler's defense against contract upgrades and // pointer aliasing, and it cannot be disabled. // The values being non-zero value makes deployment a bit more expensive, // but in exchange the refund on every call to nonReentrant will be lower in // amount. Since refunds are capped to a percentage of the total // transaction's gas, it is best to keep them low in cases like this one, to // increase the likelihood of the full refund coming into effect. uint256 private constant _NOT_ENTERED = 1; uint256 private constant _ENTERED = 2; uint256 private _status; constructor() { _status = _NOT_ENTERED; } /** * @dev Prevents a contract from calling itself, directly or indirectly. * Calling a `nonReentrant` function from another `nonReentrant` * function is not supported. It is possible to prevent this from happening * by making the `nonReentrant` function external, and making it call a * `private` function that does the actual work. */ modifier nonReentrant() { // On the first call to nonReentrant, _notEntered will be true require(_status != _ENTERED, "ReentrancyGuard: reentrant call"); // Any calls to nonReentrant after this point will fail _status = _ENTERED; _; // By storing the original value once again, a refund is triggered (see // https://eips.ethereum.org/EIPS/eip-2200) _status = _NOT_ENTERED; } } // File @openzeppelin/contracts/utils/cryptography/ECDSA.sol@v4.5.0 // OpenZeppelin Contracts (last updated v4.5.0) (utils/cryptography/ECDSA.sol) pragma solidity ^0.8.0; /** * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations. * * These functions can be used to verify that a message was signed by the holder * of the private keys of a given address. */ library ECDSA { enum RecoverError { NoError, InvalidSignature, InvalidSignatureLength, InvalidSignatureS, InvalidSignatureV } function _throwError(RecoverError error) private pure { if (error == RecoverError.NoError) { return; // no error: do nothing } else if (error == RecoverError.InvalidSignature) { revert("ECDSA: invalid signature"); } else if (error == RecoverError.InvalidSignatureLength) { revert("ECDSA: invalid signature length"); } else if (error == RecoverError.InvalidSignatureS) { revert("ECDSA: invalid signature 's' value"); } else if (error == RecoverError.InvalidSignatureV) { revert("ECDSA: invalid signature 'v' value"); } } /** * @dev Returns the address that signed a hashed message (`hash`) with * `signature` or error string. This address can then be used for verification purposes. * * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures: * this function rejects them by requiring the `s` value to be in the lower * half order, and the `v` value to be either 27 or 28. * * IMPORTANT: `hash` _must_ be the result of a hash operation for the * verification to be secure: it is possible to craft signatures that * recover to arbitrary addresses for non-hashed data. A safe way to ensure * this is by receiving a hash of the original message (which may otherwise * be too long), and then calling {toEthSignedMessageHash} on it. * * Documentation for signature generation: * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js] * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers] * * _Available since v4.3._ */ function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) { // Check the signature length // - case 65: r,s,v signature (standard) // - case 64: r,vs signature (cf https://eips.ethereum.org/EIPS/eip-2098) _Available since v4.1._ if (signature.length == 65) { bytes32 r; bytes32 s; uint8 v; // ecrecover takes the signature parameters, and the only way to get them // currently is to use assembly. assembly { r := mload(add(signature, 0x20)) s := mload(add(signature, 0x40)) v := byte(0, mload(add(signature, 0x60))) } return tryRecover(hash, v, r, s); } else if (signature.length == 64) { bytes32 r; bytes32 vs; // ecrecover takes the signature parameters, and the only way to get them // currently is to use assembly. assembly { r := mload(add(signature, 0x20)) vs := mload(add(signature, 0x40)) } return tryRecover(hash, r, vs); } else { return (address(0), RecoverError.InvalidSignatureLength); } } /** * @dev Returns the address that signed a hashed message (`hash`) with * `signature`. This address can then be used for verification purposes. * * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures: * this function rejects them by requiring the `s` value to be in the lower * half order, and the `v` value to be either 27 or 28. * * IMPORTANT: `hash` _must_ be the result of a hash operation for the * verification to be secure: it is possible to craft signatures that * recover to arbitrary addresses for non-hashed data. A safe way to ensure * this is by receiving a hash of the original message (which may otherwise * be too long), and then calling {toEthSignedMessageHash} on it. */ function recover(bytes32 hash, bytes memory signature) internal pure returns (address) { (address recovered, RecoverError error) = tryRecover(hash, signature); _throwError(error); return recovered; } /** * @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately. * * See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures] * * _Available since v4.3._ */ function tryRecover( bytes32 hash, bytes32 r, bytes32 vs ) internal pure returns (address, RecoverError) { bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff); uint8 v = uint8((uint256(vs) >> 255) + 27); return tryRecover(hash, v, r, s); } /** * @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately. * * _Available since v4.2._ */ function recover( bytes32 hash, bytes32 r, bytes32 vs ) internal pure returns (address) { (address recovered, RecoverError error) = tryRecover(hash, r, vs); _throwError(error); return recovered; } /** * @dev Overload of {ECDSA-tryRecover} that receives the `v`, * `r` and `s` signature fields separately. * * _Available since v4.3._ */ function tryRecover( bytes32 hash, uint8 v, bytes32 r, bytes32 s ) internal pure returns (address, RecoverError) { // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines // the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most // signatures from current libraries generate a unique signature with an s-value in the lower half order. // // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept // these malleable signatures as well. if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) { return (address(0), RecoverError.InvalidSignatureS); } if (v != 27 && v != 28) { return (address(0), RecoverError.InvalidSignatureV); } // If the signature is valid (and not malleable), return the signer address address signer = ecrecover(hash, v, r, s); if (signer == address(0)) { return (address(0), RecoverError.InvalidSignature); } return (signer, RecoverError.NoError); } /** * @dev Overload of {ECDSA-recover} that receives the `v`, * `r` and `s` signature fields separately. */ function recover( bytes32 hash, uint8 v, bytes32 r, bytes32 s ) internal pure returns (address) { (address recovered, RecoverError error) = tryRecover(hash, v, r, s); _throwError(error); return recovered; } /** * @dev Returns an Ethereum Signed Message, created from a `hash`. This * produces hash corresponding to the one signed with the * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`] * JSON-RPC method as part of EIP-191. * * See {recover}. */ function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) { // 32 is the length in bytes of hash, // enforced by the type signature above return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", hash)); } /** * @dev Returns an Ethereum Signed Message, created from `s`. This * produces hash corresponding to the one signed with the * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`] * JSON-RPC method as part of EIP-191. * * See {recover}. */ function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) { return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n", Strings.toString(s.length), s)); } /** * @dev Returns an Ethereum Signed Typed Data, created from a * `domainSeparator` and a `structHash`. This produces hash corresponding * to the one signed with the * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`] * JSON-RPC method as part of EIP-712. * * See {recover}. */ function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) { return keccak256(abi.encodePacked("\x19\x01", domainSeparator, structHash)); } } // File Contracts/LaunchpadNFT.sol pragma solidity ^0.8.1; contract QuixoticLaunchpadERC721 is ERC721("Early Optimists", "OPTIMISTS"), ERC721Enumerable, Ownable, ReentrancyGuard { string private _baseURIextended; string private _baseURISuffix = ""; bool public frozenMetadata = false; uint256 public MAX_TOKENS = 36000; bool public saleIsActive = false; bool public greenListSaleIsActive = false; mapping(address => uint256) addressToGreenListNumberMinted; mapping(address => uint256) addressToNumberMinted; address private bouncer = 0xd47257ee6cD0a80Ed1ba7bDdC722Ef8eE44a8d7d; bool private _baseUriIncludeTokenId = true; function _beforeTokenTransfer(address from, address to, uint256 tokenId) internal override(ERC721, ERC721Enumerable) { super._beforeTokenTransfer(from, to, tokenId); } function supportsInterface(bytes4 interfaceId) public view virtual override(ERC721, ERC721Enumerable) returns (bool) { return super.supportsInterface(interfaceId); } function flipSaleState() public onlyOwner { saleIsActive = !saleIsActive; } function flipGreenListSaleState() public onlyOwner { greenListSaleIsActive = !greenListSaleIsActive; } function setBaseURI(string memory baseURI_, bool includeTokenId, string memory suffix) external onlyOwner() { require(!frozenMetadata, "The metadata URI is frozen. You can no longer set the baseURI"); _baseUriIncludeTokenId = includeTokenId; _baseURIextended = baseURI_; _baseURISuffix = suffix; } function _baseURI() internal view virtual override returns (string memory) { return _baseURIextended; } function freezeMetadata() external onlyOwner { frozenMetadata = true; } function tokenURI(uint256 tokenId) public view virtual override returns (string memory) { require(_exists(tokenId), "ERC721Metadata: URI query for nonexistent token"); string memory baseURI = _baseURI(); if (_baseUriIncludeTokenId) { return bytes(baseURI).length > 0 ? string(abi.encodePacked(baseURI, Strings.toString(tokenId), _baseURISuffix)) : ""; } else { return bytes(baseURI).length > 0 ? string(abi.encodePacked(baseURI)) : ""; } } function mintToken(uint numberOfTokens) public payable nonReentrant { require(tx.origin == _msgSender(), "This function is only callable from an EOA."); require(saleIsActive, "Sale must be active to mint Tokens"); require(numberOfTokens + addressToNumberMinted[_msgSender()] <= 1, "Exceeded max token purchase"); require(totalSupply() + numberOfTokens <= MAX_TOKENS, "Purchase would exceed max supply of tokens"); require(0 * numberOfTokens <= msg.value, "Ether value sent is not correct"); for (uint i = 0; i < numberOfTokens; i++) { uint mintIndex = totalSupply(); if (totalSupply() < MAX_TOKENS) { addressToNumberMinted[_msgSender()] += 1; _safeMint(_msgSender(), mintIndex); } } } function greenListMintToken(uint numberOfTokens, bytes memory signature) public payable nonReentrant { require(tx.origin == _msgSender(), "This function is only callable from an EOA."); require(greenListSaleIsActive, "Sale must be active to mint Tokens"); require(numberOfTokens + addressToGreenListNumberMinted[_msgSender()] <= 1, "Exceeded max token purchase"); require(totalSupply() + numberOfTokens <= MAX_TOKENS, "Purchase would exceed max supply of tokens"); require(0 * numberOfTokens <= msg.value, "Ether value sent is not correct"); bytes32 hashedMinter = ECDSA.toEthSignedMessageHash(keccak256(abi.encodePacked(_msgSender()))); address recoveredBouncer = ECDSA.recover(hashedMinter, signature); require(recoveredBouncer == bouncer, "The signature for the greenlist is invalid"); for (uint i = 0; i < numberOfTokens; i++) { uint mintIndex = totalSupply(); if (totalSupply() < MAX_TOKENS) { addressToGreenListNumberMinted[_msgSender()] += 1; _safeMint(_msgSender(), mintIndex); } } } function reserveTokens(uint quantity, address recipient) public onlyOwner { uint supply = totalSupply(); require(supply + quantity <= MAX_TOKENS, "We have already hit the reserve limit"); uint i; for (i = 0; i < quantity; i++) { uint mintIndex = totalSupply(); _safeMint(recipient, mintIndex); } } }