| { | |
| "language": "Solidity", | |
| "sources": { | |
| "contracts/Subscriptions.sol": { | |
| "content": "//SPDX-License-Identifier: MIT\npragma solidity ^0.8.9;\n\nimport \"@openzeppelin/contracts/token/ERC20/ERC20.sol\";\nimport \"@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol\";\n\ncontract Subscriptions is ERC721Enumerable {\n uint256 constant public fee = 10e18;\n\n ERC20 immutable public dai;\n address immutable public owner;\n\n uint256 public nextToken = 1;\n mapping(uint256 => uint256) public subscriptions;\n\n event Subscribe(address indexed user);\n event Sweep(address indexed owner, uint256 balance);\n\n constructor(address _dai) ERC721(\"Dexcalidraw - Pendragon Plan - One Year Subscription\", \"Pendragon-1YR\") {\n dai = ERC20(_dai);\n owner = msg.sender;\n }\n\n function subscribe() public {\n dai.transferFrom(msg.sender, address(this), fee);\n subscriptions[nextToken] = block.timestamp;\n _safeMint(msg.sender, nextToken);\n nextToken++;\n emit Subscribe(msg.sender);\n }\n\n function expired(uint256 token) public view returns (bool) {\n uint256 elapsed = block.timestamp - subscriptions[token];\n return elapsed > (365 days);\n }\n\n function sweep() public {\n require(msg.sender == owner, \"!owner\");\n uint256 balance = dai.balanceOf(address(this));\n dai.transferFrom(address(this), msg.sender, balance);\n emit Sweep(msg.sender, balance);\n }\n}" | |
| }, | |
| "@openzeppelin/contracts/token/ERC20/ERC20.sol": { | |
| "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC20/ERC20.sol)\n\npragma solidity ^0.8.0;\n\nimport \"./IERC20.sol\";\nimport \"./extensions/IERC20Metadata.sol\";\nimport \"../../utils/Context.sol\";\n\n/**\n * @dev Implementation of the {IERC20} interface.\n *\n * This implementation is agnostic to the way tokens are created. This means\n * that a supply mechanism has to be added in a derived contract using {_mint}.\n * For a generic mechanism see {ERC20PresetMinterPauser}.\n *\n * TIP: For a detailed writeup see our guide\n * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How\n * to implement supply mechanisms].\n *\n * We have followed general OpenZeppelin Contracts guidelines: functions revert\n * instead returning `false` on failure. This behavior is nonetheless\n * conventional and does not conflict with the expectations of ERC20\n * applications.\n *\n * Additionally, an {Approval} event is emitted on calls to {transferFrom}.\n * This allows applications to reconstruct the allowance for all accounts just\n * by listening to said events. Other implementations of the EIP may not emit\n * these events, as it isn't required by the specification.\n *\n * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}\n * functions have been added to mitigate the well-known issues around setting\n * allowances. See {IERC20-approve}.\n */\ncontract ERC20 is Context, IERC20, IERC20Metadata {\n mapping(address => uint256) private _balances;\n\n mapping(address => mapping(address => uint256)) private _allowances;\n\n uint256 private _totalSupply;\n\n string private _name;\n string private _symbol;\n\n /**\n * @dev Sets the values for {name} and {symbol}.\n *\n * The default value of {decimals} is 18. To select a different value for\n * {decimals} you should overload it.\n *\n * All two of these values are immutable: they can only be set once during\n * construction.\n */\n constructor(string memory name_, string memory symbol_) {\n _name = name_;\n _symbol = symbol_;\n }\n\n /**\n * @dev Returns the name of the token.\n */\n function name() public view virtual override returns (string memory) {\n return _name;\n }\n\n /**\n * @dev Returns the symbol of the token, usually a shorter version of the\n * name.\n */\n function symbol() public view virtual override returns (string memory) {\n return _symbol;\n }\n\n /**\n * @dev Returns the number of decimals used to get its user representation.\n * For example, if `decimals` equals `2`, a balance of `505` tokens should\n * be displayed to a user as `5.05` (`505 / 10 ** 2`).\n *\n * Tokens usually opt for a value of 18, imitating the relationship between\n * Ether and Wei. This is the value {ERC20} uses, unless this function is\n * overridden;\n *\n * NOTE: This information is only used for _display_ purposes: it in\n * no way affects any of the arithmetic of the contract, including\n * {IERC20-balanceOf} and {IERC20-transfer}.\n */\n function decimals() public view virtual override returns (uint8) {\n return 18;\n }\n\n /**\n * @dev See {IERC20-totalSupply}.\n */\n function totalSupply() public view virtual override returns (uint256) {\n return _totalSupply;\n }\n\n /**\n * @dev See {IERC20-balanceOf}.\n */\n function balanceOf(address account) public view virtual override returns (uint256) {\n return _balances[account];\n }\n\n /**\n * @dev See {IERC20-transfer}.\n *\n * Requirements:\n *\n * - `to` cannot be the zero address.\n * - the caller must have a balance of at least `amount`.\n */\n function transfer(address to, uint256 amount) public virtual override returns (bool) {\n address owner = _msgSender();\n _transfer(owner, to, amount);\n return true;\n }\n\n /**\n * @dev See {IERC20-allowance}.\n */\n function allowance(address owner, address spender) public view virtual override returns (uint256) {\n return _allowances[owner][spender];\n }\n\n /**\n * @dev See {IERC20-approve}.\n *\n * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on\n * `transferFrom`. This is semantically equivalent to an infinite approval.\n *\n * Requirements:\n *\n * - `spender` cannot be the zero address.\n */\n function approve(address spender, uint256 amount) public virtual override returns (bool) {\n address owner = _msgSender();\n _approve(owner, spender, amount);\n return true;\n }\n\n /**\n * @dev See {IERC20-transferFrom}.\n *\n * Emits an {Approval} event indicating the updated allowance. This is not\n * required by the EIP. See the note at the beginning of {ERC20}.\n *\n * NOTE: Does not update the allowance if the current allowance\n * is the maximum `uint256`.\n *\n * Requirements:\n *\n * - `from` and `to` cannot be the zero address.\n * - `from` must have a balance of at least `amount`.\n * - the caller must have allowance for ``from``'s tokens of at least\n * `amount`.\n */\n function transferFrom(\n address from,\n address to,\n uint256 amount\n ) public virtual override returns (bool) {\n address spender = _msgSender();\n _spendAllowance(from, spender, amount);\n _transfer(from, to, amount);\n return true;\n }\n\n /**\n * @dev Atomically increases the allowance granted to `spender` by the caller.\n *\n * This is an alternative to {approve} that can be used as a mitigation for\n * problems described in {IERC20-approve}.\n *\n * Emits an {Approval} event indicating the updated allowance.\n *\n * Requirements:\n *\n * - `spender` cannot be the zero address.\n */\n function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {\n address owner = _msgSender();\n _approve(owner, spender, allowance(owner, spender) + addedValue);\n return true;\n }\n\n /**\n * @dev Atomically decreases the allowance granted to `spender` by the caller.\n *\n * This is an alternative to {approve} that can be used as a mitigation for\n * problems described in {IERC20-approve}.\n *\n * Emits an {Approval} event indicating the updated allowance.\n *\n * Requirements:\n *\n * - `spender` cannot be the zero address.\n * - `spender` must have allowance for the caller of at least\n * `subtractedValue`.\n */\n function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {\n address owner = _msgSender();\n uint256 currentAllowance = allowance(owner, spender);\n require(currentAllowance >= subtractedValue, \"ERC20: decreased allowance below zero\");\n unchecked {\n _approve(owner, spender, currentAllowance - subtractedValue);\n }\n\n return true;\n }\n\n /**\n * @dev Moves `amount` of tokens from `from` to `to`.\n *\n * This internal function is equivalent to {transfer}, and can be used to\n * e.g. implement automatic token fees, slashing mechanisms, etc.\n *\n * Emits a {Transfer} event.\n *\n * Requirements:\n *\n * - `from` cannot be the zero address.\n * - `to` cannot be the zero address.\n * - `from` must have a balance of at least `amount`.\n */\n function _transfer(\n address from,\n address to,\n uint256 amount\n ) internal virtual {\n require(from != address(0), \"ERC20: transfer from the zero address\");\n require(to != address(0), \"ERC20: transfer to the zero address\");\n\n _beforeTokenTransfer(from, to, amount);\n\n uint256 fromBalance = _balances[from];\n require(fromBalance >= amount, \"ERC20: transfer amount exceeds balance\");\n unchecked {\n _balances[from] = fromBalance - amount;\n }\n _balances[to] += amount;\n\n emit Transfer(from, to, amount);\n\n _afterTokenTransfer(from, to, amount);\n }\n\n /** @dev Creates `amount` tokens and assigns them to `account`, increasing\n * the total supply.\n *\n * Emits a {Transfer} event with `from` set to the zero address.\n *\n * Requirements:\n *\n * - `account` cannot be the zero address.\n */\n function _mint(address account, uint256 amount) internal virtual {\n require(account != address(0), \"ERC20: mint to the zero address\");\n\n _beforeTokenTransfer(address(0), account, amount);\n\n _totalSupply += amount;\n _balances[account] += amount;\n emit Transfer(address(0), account, amount);\n\n _afterTokenTransfer(address(0), account, amount);\n }\n\n /**\n * @dev Destroys `amount` tokens from `account`, reducing the\n * total supply.\n *\n * Emits a {Transfer} event with `to` set to the zero address.\n *\n * Requirements:\n *\n * - `account` cannot be the zero address.\n * - `account` must have at least `amount` tokens.\n */\n function _burn(address account, uint256 amount) internal virtual {\n require(account != address(0), \"ERC20: burn from the zero address\");\n\n _beforeTokenTransfer(account, address(0), amount);\n\n uint256 accountBalance = _balances[account];\n require(accountBalance >= amount, \"ERC20: burn amount exceeds balance\");\n unchecked {\n _balances[account] = accountBalance - amount;\n }\n _totalSupply -= amount;\n\n emit Transfer(account, address(0), amount);\n\n _afterTokenTransfer(account, address(0), amount);\n }\n\n /**\n * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.\n *\n * This internal function is equivalent to `approve`, and can be used to\n * e.g. set automatic allowances for certain subsystems, etc.\n *\n * Emits an {Approval} event.\n *\n * Requirements:\n *\n * - `owner` cannot be the zero address.\n * - `spender` cannot be the zero address.\n */\n function _approve(\n address owner,\n address spender,\n uint256 amount\n ) internal virtual {\n require(owner != address(0), \"ERC20: approve from the zero address\");\n require(spender != address(0), \"ERC20: approve to the zero address\");\n\n _allowances[owner][spender] = amount;\n emit Approval(owner, spender, amount);\n }\n\n /**\n * @dev Updates `owner` s allowance for `spender` based on spent `amount`.\n *\n * Does not update the allowance amount in case of infinite allowance.\n * Revert if not enough allowance is available.\n *\n * Might emit an {Approval} event.\n */\n function _spendAllowance(\n address owner,\n address spender,\n uint256 amount\n ) internal virtual {\n uint256 currentAllowance = allowance(owner, spender);\n if (currentAllowance != type(uint256).max) {\n require(currentAllowance >= amount, \"ERC20: insufficient allowance\");\n unchecked {\n _approve(owner, spender, currentAllowance - amount);\n }\n }\n }\n\n /**\n * @dev Hook that is called before any transfer of tokens. This includes\n * minting and burning.\n *\n * Calling conditions:\n *\n * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens\n * will be transferred to `to`.\n * - when `from` is zero, `amount` tokens will be minted for `to`.\n * - when `to` is zero, `amount` of ``from``'s tokens 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(\n address from,\n address to,\n uint256 amount\n ) internal virtual {}\n\n /**\n * @dev Hook that is called after any transfer of tokens. This includes\n * minting and burning.\n *\n * Calling conditions:\n *\n * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens\n * has been transferred to `to`.\n * - when `from` is zero, `amount` tokens have been minted for `to`.\n * - when `to` is zero, `amount` of ``from``'s tokens have been 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 _afterTokenTransfer(\n address from,\n address to,\n uint256 amount\n ) internal virtual {}\n}\n" | |
| }, | |
| "@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol": { | |
| "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/ERC721Enumerable.sol)\n\npragma solidity ^0.8.0;\n\nimport \"../ERC721.sol\";\nimport \"./IERC721Enumerable.sol\";\n\n/**\n * @dev This implements an optional extension of {ERC721} defined in the EIP that adds\n * enumerability of all the token ids in the contract as well as all token ids owned by each\n * account.\n */\nabstract contract ERC721Enumerable is ERC721, 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, ERC721) returns (bool) {\n return interfaceId == type(IERC721Enumerable).interfaceId || 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 < ERC721.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 < ERC721Enumerable.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(\n address from,\n address to,\n uint256 tokenId\n ) 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 = ERC721.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 = ERC721.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" | |
| }, | |
| "@openzeppelin/contracts/utils/Context.sol": { | |
| "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Provides information about the current execution context, including the\n * sender of the transaction and its data. While these are generally available\n * via msg.sender and msg.data, they should not be accessed in such a direct\n * manner, since when dealing with meta-transactions the account sending and\n * paying for execution may not be the actual sender (as far as an application\n * is concerned).\n *\n * This contract is only required for intermediate, library-like contracts.\n */\nabstract contract Context {\n function _msgSender() internal view virtual returns (address) {\n return msg.sender;\n }\n\n function _msgData() internal view virtual returns (bytes calldata) {\n return msg.data;\n }\n}\n" | |
| }, | |
| "@openzeppelin/contracts/token/ERC20/IERC20.sol": { | |
| "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Interface of the ERC20 standard as defined in the EIP.\n */\ninterface IERC20 {\n /**\n * @dev Emitted when `value` tokens are moved from one account (`from`) to\n * another (`to`).\n *\n * Note that `value` may be zero.\n */\n event Transfer(address indexed from, address indexed to, uint256 value);\n\n /**\n * @dev Emitted when the allowance of a `spender` for an `owner` is set by\n * a call to {approve}. `value` is the new allowance.\n */\n event Approval(address indexed owner, address indexed spender, uint256 value);\n\n /**\n * @dev Returns the amount of tokens in existence.\n */\n function totalSupply() external view returns (uint256);\n\n /**\n * @dev Returns the amount of tokens owned by `account`.\n */\n function balanceOf(address account) external view returns (uint256);\n\n /**\n * @dev Moves `amount` tokens from the caller's account to `to`.\n *\n * Returns a boolean value indicating whether the operation succeeded.\n *\n * Emits a {Transfer} event.\n */\n function transfer(address to, uint256 amount) external returns (bool);\n\n /**\n * @dev Returns the remaining number of tokens that `spender` will be\n * allowed to spend on behalf of `owner` through {transferFrom}. This is\n * zero by default.\n *\n * This value changes when {approve} or {transferFrom} are called.\n */\n function allowance(address owner, address spender) external view returns (uint256);\n\n /**\n * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.\n *\n * Returns a boolean value indicating whether the operation succeeded.\n *\n * IMPORTANT: Beware that changing an allowance with this method brings the risk\n * that someone may use both the old and the new allowance by unfortunate\n * transaction ordering. One possible solution to mitigate this race\n * condition is to first reduce the spender's allowance to 0 and set the\n * desired value afterwards:\n * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729\n *\n * Emits an {Approval} event.\n */\n function approve(address spender, uint256 amount) external returns (bool);\n\n /**\n * @dev Moves `amount` tokens from `from` to `to` using the\n * allowance mechanism. `amount` is then deducted from the caller's\n * allowance.\n *\n * Returns a boolean value indicating whether the operation succeeded.\n *\n * Emits a {Transfer} event.\n */\n function transferFrom(\n address from,\n address to,\n uint256 amount\n ) external returns (bool);\n}\n" | |
| }, | |
| "@openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol": { | |
| "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)\n\npragma solidity ^0.8.0;\n\nimport \"../IERC20.sol\";\n\n/**\n * @dev Interface for the optional metadata functions from the ERC20 standard.\n *\n * _Available since v4.1._\n */\ninterface IERC20Metadata is IERC20 {\n /**\n * @dev Returns the name of the token.\n */\n function name() external view returns (string memory);\n\n /**\n * @dev Returns the symbol of the token.\n */\n function symbol() external view returns (string memory);\n\n /**\n * @dev Returns the decimals places of the token.\n */\n function decimals() external view returns (uint8);\n}\n" | |
| }, | |
| "@openzeppelin/contracts/token/ERC721/ERC721.sol": { | |
| "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC721/ERC721.sol)\n\npragma solidity ^0.8.0;\n\nimport \"./IERC721.sol\";\nimport \"./IERC721Receiver.sol\";\nimport \"./extensions/IERC721Metadata.sol\";\nimport \"../../utils/Address.sol\";\nimport \"../../utils/Context.sol\";\nimport \"../../utils/Strings.sol\";\nimport \"../../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 */\ncontract ERC721 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 // 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(string memory name_, string memory symbol_) {\n _name = name_;\n _symbol = symbol_;\n }\n\n /**\n * @dev See {IERC165-supportsInterface}.\n */\n function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {\n return\n interfaceId == type(IERC721).interfaceId ||\n interfaceId == type(IERC721Metadata).interfaceId ||\n super.supportsInterface(interfaceId);\n }\n\n /**\n * @dev See {IERC721-balanceOf}.\n */\n function balanceOf(address owner) public view virtual override returns (uint256) {\n require(owner != address(0), \"ERC721: address zero is not a valid owner\");\n return _balances[owner];\n }\n\n /**\n * @dev See {IERC721-ownerOf}.\n */\n function ownerOf(uint256 tokenId) public view virtual override returns (address) {\n address owner = _owners[tokenId];\n require(owner != address(0), \"ERC721: invalid token ID\");\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 _requireMinted(tokenId);\n\n string memory baseURI = _baseURI();\n return bytes(baseURI).length > 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : \"\";\n }\n\n /**\n * @dev Base URI for computing {tokenURI}. If set, the resulting URI for each\n * token will be the concatenation of the `baseURI` and the `tokenId`. Empty\n * by default, can be overridden 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 = ERC721.ownerOf(tokenId);\n require(to != owner, \"ERC721: approval to current owner\");\n\n require(\n _msgSender() == owner || isApprovedForAll(owner, _msgSender()),\n \"ERC721: approve caller is not token 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 _requireMinted(tokenId);\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 _setApprovalForAll(_msgSender(), operator, approved);\n }\n\n /**\n * @dev See {IERC721-isApprovedForAll}.\n */\n function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {\n return _operatorApprovals[owner][operator];\n }\n\n /**\n * @dev See {IERC721-transferFrom}.\n */\n function transferFrom(\n address from,\n address to,\n uint256 tokenId\n ) public virtual override {\n //solhint-disable-next-line max-line-length\n require(_isApprovedOrOwner(_msgSender(), tokenId), \"ERC721: caller is not token owner nor approved\");\n\n _transfer(from, to, tokenId);\n }\n\n /**\n * @dev See {IERC721-safeTransferFrom}.\n */\n function safeTransferFrom(\n address from,\n address to,\n uint256 tokenId\n ) public virtual override {\n safeTransferFrom(from, to, tokenId, \"\");\n }\n\n /**\n * @dev See {IERC721-safeTransferFrom}.\n */\n function safeTransferFrom(\n address from,\n address to,\n uint256 tokenId,\n bytes memory data\n ) public virtual override {\n require(_isApprovedOrOwner(_msgSender(), tokenId), \"ERC721: caller is not token 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(\n address from,\n address to,\n uint256 tokenId,\n bytes memory data\n ) 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 address owner = ERC721.ownerOf(tokenId);\n return (spender == owner || isApprovedForAll(owner, spender) || getApproved(tokenId) == 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(\n address to,\n uint256 tokenId,\n bytes memory data\n ) internal virtual {\n _mint(to, tokenId);\n require(\n _checkOnERC721Received(address(0), to, tokenId, data),\n \"ERC721: transfer to non ERC721Receiver implementer\"\n );\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 _afterTokenTransfer(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 address owner = ERC721.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 _afterTokenTransfer(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(\n address from,\n address to,\n uint256 tokenId\n ) internal virtual {\n require(ERC721.ownerOf(tokenId) == from, \"ERC721: transfer from incorrect owner\");\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 _afterTokenTransfer(from, to, tokenId);\n }\n\n /**\n * @dev Approve `to` to operate on `tokenId`\n *\n * Emits an {Approval} event.\n */\n function _approve(address to, uint256 tokenId) internal virtual {\n _tokenApprovals[tokenId] = to;\n emit Approval(ERC721.ownerOf(tokenId), to, tokenId);\n }\n\n /**\n * @dev Approve `operator` to operate on all of `owner` tokens\n *\n * Emits an {ApprovalForAll} event.\n */\n function _setApprovalForAll(\n address owner,\n address operator,\n bool approved\n ) internal virtual {\n require(owner != operator, \"ERC721: approve to caller\");\n _operatorApprovals[owner][operator] = approved;\n emit ApprovalForAll(owner, operator, approved);\n }\n\n /**\n * @dev Reverts if the `tokenId` has not been minted yet.\n */\n function _requireMinted(uint256 tokenId) internal view virtual {\n require(_exists(tokenId), \"ERC721: invalid token ID\");\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(\n address from,\n address to,\n uint256 tokenId,\n bytes memory data\n ) private returns (bool) {\n if (to.isContract()) {\n try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, data) returns (bytes4 retval) {\n return retval == IERC721Receiver.onERC721Received.selector;\n } catch (bytes memory reason) {\n if (reason.length == 0) {\n revert(\"ERC721: transfer to non ERC721Receiver implementer\");\n } else {\n /// @solidity memory-safe-assembly\n assembly {\n revert(add(32, reason), mload(reason))\n }\n }\n }\n } else {\n return true;\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(\n address from,\n address to,\n uint256 tokenId\n ) internal virtual {}\n\n /**\n * @dev Hook that is called after any transfer of tokens. This includes\n * minting and burning.\n *\n * Calling conditions:\n *\n * - when `from` and `to` are both non-zero.\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 _afterTokenTransfer(\n address from,\n address to,\n uint256 tokenId\n ) internal virtual {}\n}\n" | |
| }, | |
| "@openzeppelin/contracts/token/ERC721/extensions/IERC721Enumerable.sol": { | |
| "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC721/extensions/IERC721Enumerable.sol)\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 * @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);\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/utils/Strings.sol": { | |
| "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.7.0) (utils/Strings.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev String operations.\n */\nlibrary Strings {\n bytes16 private constant _HEX_SYMBOLS = \"0123456789abcdef\";\n uint8 private constant _ADDRESS_LENGTH = 20;\n\n /**\n * @dev Converts a `uint256` to its ASCII `string` decimal representation.\n */\n function toString(uint256 value) internal pure returns (string memory) {\n // Inspired by OraclizeAPI's implementation - MIT licence\n // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol\n\n if (value == 0) {\n return \"0\";\n }\n uint256 temp = value;\n uint256 digits;\n while (temp != 0) {\n digits++;\n temp /= 10;\n }\n bytes memory buffer = new bytes(digits);\n while (value != 0) {\n digits -= 1;\n buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));\n value /= 10;\n }\n return string(buffer);\n }\n\n /**\n * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.\n */\n function toHexString(uint256 value) internal pure returns (string memory) {\n if (value == 0) {\n return \"0x00\";\n }\n uint256 temp = value;\n uint256 length = 0;\n while (temp != 0) {\n length++;\n temp >>= 8;\n }\n return toHexString(value, length);\n }\n\n /**\n * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.\n */\n function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {\n bytes memory buffer = new bytes(2 * length + 2);\n buffer[0] = \"0\";\n buffer[1] = \"x\";\n for (uint256 i = 2 * length + 1; i > 1; --i) {\n buffer[i] = _HEX_SYMBOLS[value & 0xf];\n value >>= 4;\n }\n require(value == 0, \"Strings: hex length insufficient\");\n return string(buffer);\n }\n\n /**\n * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.\n */\n function toHexString(address addr) internal pure returns (string memory) {\n return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);\n }\n}\n" | |
| }, | |
| "@openzeppelin/contracts/utils/Address.sol": { | |
| "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)\n\npragma solidity ^0.8.1;\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 * [IMPORTANT]\n * ====\n * You shouldn't rely on `isContract` to protect against flash loan attacks!\n *\n * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets\n * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract\n * constructor.\n * ====\n */\n function isContract(address account) internal view returns (bool) {\n // This method relies on extcodesize/address.code.length, which returns 0\n // for contracts in construction, since the code is only stored at the end\n // of the constructor execution.\n\n return account.code.length > 0;\n }\n\n /**\n * @dev Replacement for Solidity's `transfer`: sends `amount` wei to\n * `recipient`, forwarding all available gas and reverting on errors.\n *\n * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost\n * of certain opcodes, possibly making contracts go over the 2300 gas limit\n * imposed by `transfer`, making them unable to receive funds via\n * `transfer`. {sendValue} removes this limitation.\n *\n * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].\n *\n * IMPORTANT: because control is transferred to `recipient`, care must be\n * taken to not create reentrancy vulnerabilities. Consider using\n * {ReentrancyGuard} or the\n * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].\n */\n function sendValue(address payable recipient, uint256 amount) internal {\n require(address(this).balance >= amount, \"Address: insufficient balance\");\n\n (bool success, ) = recipient.call{value: amount}(\"\");\n require(success, \"Address: unable to send value, recipient may have reverted\");\n }\n\n /**\n * @dev Performs a Solidity function call using a low level `call`. A\n * plain `call` is an unsafe replacement for a function call: use this\n * function instead.\n *\n * If `target` reverts with a revert reason, it is bubbled up by this\n * function (like regular Solidity function calls).\n *\n * Returns the raw returned data. To convert to the expected return value,\n * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].\n *\n * Requirements:\n *\n * - `target` must be a contract.\n * - calling `target` with `data` must not revert.\n *\n * _Available since v3.1._\n */\n function functionCall(address target, bytes memory data) internal returns (bytes memory) {\n return functionCall(target, data, \"Address: low-level call failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with\n * `errorMessage` as a fallback revert reason when `target` reverts.\n *\n * _Available since v3.1._\n */\n function functionCall(\n address target,\n bytes memory data,\n string memory errorMessage\n ) internal returns (bytes memory) {\n return functionCallWithValue(target, data, 0, errorMessage);\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n * but also transferring `value` wei to `target`.\n *\n * Requirements:\n *\n * - the calling contract must have an ETH balance of at least `value`.\n * - the called Solidity function must be `payable`.\n *\n * _Available since v3.1._\n */\n function functionCallWithValue(\n address target,\n bytes memory data,\n uint256 value\n ) internal returns (bytes memory) {\n return functionCallWithValue(target, data, value, \"Address: low-level call with value failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but\n * with `errorMessage` as a fallback revert reason when `target` reverts.\n *\n * _Available since v3.1._\n */\n function functionCallWithValue(\n address target,\n bytes memory data,\n uint256 value,\n string memory errorMessage\n ) internal returns (bytes memory) {\n require(address(this).balance >= value, \"Address: insufficient balance for call\");\n require(isContract(target), \"Address: call to non-contract\");\n\n (bool success, bytes memory returndata) = target.call{value: value}(data);\n return verifyCallResult(success, returndata, errorMessage);\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n * but performing a static call.\n *\n * _Available since v3.3._\n */\n function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {\n return functionStaticCall(target, data, \"Address: low-level static call failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n * but performing a static call.\n *\n * _Available since v3.3._\n */\n function functionStaticCall(\n address target,\n bytes memory data,\n string memory errorMessage\n ) internal view returns (bytes memory) {\n require(isContract(target), \"Address: static call to non-contract\");\n\n (bool success, bytes memory returndata) = target.staticcall(data);\n return verifyCallResult(success, returndata, errorMessage);\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n * but performing a delegate call.\n *\n * _Available since v3.4._\n */\n function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {\n return functionDelegateCall(target, data, \"Address: low-level delegate call failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n * but performing a delegate call.\n *\n * _Available since v3.4._\n */\n function functionDelegateCall(\n address target,\n bytes memory data,\n string memory errorMessage\n ) internal returns (bytes memory) {\n require(isContract(target), \"Address: delegate call to non-contract\");\n\n (bool success, bytes memory returndata) = target.delegatecall(data);\n return verifyCallResult(success, returndata, errorMessage);\n }\n\n /**\n * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the\n * revert reason using the provided one.\n *\n * _Available since v4.3._\n */\n function verifyCallResult(\n bool success,\n bytes memory returndata,\n string memory errorMessage\n ) internal pure returns (bytes memory) {\n if (success) {\n return returndata;\n } else {\n // Look for revert reason and bubble it up if present\n if (returndata.length > 0) {\n // The easiest way to bubble the revert reason is using memory via assembly\n /// @solidity memory-safe-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/IERC721.sol": { | |
| "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC721/IERC721.sol)\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`.\n *\n * Requirements:\n *\n * - `from` cannot be the zero address.\n * - `to` cannot be the zero address.\n * - `tokenId` token must exist and be owned by `from`.\n * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.\n * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.\n *\n * Emits a {Transfer} event.\n */\n function safeTransferFrom(\n address from,\n address to,\n uint256 tokenId,\n bytes calldata data\n ) external;\n\n /**\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 have been allowed to move this token by either {approve} or {setApprovalForAll}.\n * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.\n *\n * Emits a {Transfer} event.\n */\n function safeTransferFrom(\n address from,\n address to,\n uint256 tokenId\n ) external;\n\n /**\n * @dev Transfers `tokenId` token from `from` to `to`.\n *\n * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.\n *\n * Requirements:\n *\n * - `from` cannot be the zero address.\n * - `to` cannot be the zero address.\n * - `tokenId` token must be owned by `from`.\n * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.\n *\n * Emits a {Transfer} event.\n */\n function transferFrom(\n address from,\n address to,\n uint256 tokenId\n ) external;\n\n /**\n * @dev Gives permission to `to` to transfer `tokenId` token to another account.\n * The approval is cleared when the token is transferred.\n *\n * Only a single account can be approved at a time, so approving the zero address clears previous approvals.\n *\n * Requirements:\n *\n * - The caller must own the token or be an approved operator.\n * - `tokenId` must exist.\n *\n * Emits an {Approval} event.\n */\n function approve(address to, uint256 tokenId) external;\n\n /**\n * @dev 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 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 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" | |
| }, | |
| "@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol": { | |
| "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC721/IERC721Receiver.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @title ERC721 token receiver interface\n * @dev Interface for any contract that wants to support safeTransfers\n * from ERC721 asset contracts.\n */\ninterface IERC721Receiver {\n /**\n * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}\n * by `operator` from `from`, this function is called.\n *\n * It must return its Solidity selector to confirm the token transfer.\n * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.\n *\n * The selector can be obtained in Solidity with `IERC721Receiver.onERC721Received.selector`.\n */\n function onERC721Received(\n address operator,\n address from,\n uint256 tokenId,\n bytes calldata data\n ) external returns (bytes4);\n}\n" | |
| }, | |
| "@openzeppelin/contracts/utils/introspection/ERC165.sol": { | |
| "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)\n\npragma solidity ^0.8.0;\n\nimport \"./IERC165.sol\";\n\n/**\n * @dev Implementation of the {IERC165} interface.\n *\n * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check\n * for the additional interface id that will be supported. For example:\n *\n * ```solidity\n * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {\n * return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);\n * }\n * ```\n *\n * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.\n */\nabstract contract ERC165 is IERC165 {\n /**\n * @dev See {IERC165-supportsInterface}.\n */\n function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {\n return interfaceId == type(IERC165).interfaceId;\n }\n}\n" | |
| }, | |
| "@openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol": { | |
| "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/IERC721Metadata.sol)\n\npragma solidity ^0.8.0;\n\nimport \"../IERC721.sol\";\n\n/**\n * @title ERC-721 Non-Fungible Token Standard, optional metadata extension\n * @dev See https://eips.ethereum.org/EIPS/eip-721\n */\ninterface IERC721Metadata is IERC721 {\n /**\n * @dev Returns the token collection name.\n */\n function name() external view returns (string memory);\n\n /**\n * @dev Returns the token collection symbol.\n */\n function symbol() external view returns (string memory);\n\n /**\n * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.\n */\n function tokenURI(uint256 tokenId) external view returns (string memory);\n}\n" | |
| }, | |
| "@openzeppelin/contracts/utils/introspection/IERC165.sol": { | |
| "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Interface of the ERC165 standard, as defined in the\n * https://eips.ethereum.org/EIPS/eip-165[EIP].\n *\n * Implementers can declare support of contract interfaces, which can then be\n * queried by others ({ERC165Checker}).\n *\n * For an implementation, see {ERC165}.\n */\ninterface IERC165 {\n /**\n * @dev Returns true if this contract implements the interface defined by\n * `interfaceId`. See the corresponding\n * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]\n * to learn more about how these ids are created.\n *\n * This function call must use less than 30 000 gas.\n */\n function supportsInterface(bytes4 interfaceId) external view returns (bool);\n}\n" | |
| } | |
| }, | |
| "settings": { | |
| "optimizer": { | |
| "enabled": false, | |
| "runs": 200 | |
| }, | |
| "outputSelection": { | |
| "*": { | |
| "*": [ | |
| "evm.bytecode", | |
| "evm.deployedBytecode", | |
| "devdoc", | |
| "userdoc", | |
| "metadata", | |
| "abi" | |
| ] | |
| } | |
| }, | |
| "libraries": {} | |
| } | |
| } |