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{
"language": "Solidity",
"sources": {
"contracts/ptc_nft.sol": {
"content": "// SPDX-License-Identifier: MIT\n\npragma solidity 0.8.9;\n\nimport \"@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol\";\nimport \"@openzeppelin/contracts/access/Ownable.sol\";\nimport \"@openzeppelin/contracts/security/ReentrancyGuard.sol\";\n\ncontract PalmTreeCollective is ERC721Enumerable, Ownable, ReentrancyGuard {\n\n // Events\n event Burn(uint256 tokenId, address burner);\n\n // Constants\n uint256 public constant TOKEN_LIMIT = 1000;\n uint256 public constant PRESALE_MINT_LIMIT = 100;\n uint256 public constant MAX_MINT_QUANTITY = 5;\n uint256 private constant _GIVEAWAY_LIMIT = 100;\n\n uint256 public mint_price = .1 ether;\n\n // Addresses\n address payable constant private _PT_WALLET = payable(0x452A89F1316798fDdC9D03f9af38b0586F8142e5);\n\n // States\n uint256 public sale_state = 3; // 0 = closed, 1 = presale tier 1, 2 = presale tier 2, 3 = sale\n bool public burn_active = false;\n\n // General\n string public baseURI;\n string public PROVENANCE_HASH = \"\";\n\n // Internal state\n // _presale_allowance[address] > 0 | tier 2 eligible\n // _presale_allowance[address] - 1 | remaining tier 1 mints\n mapping(address => uint256) private _presale_allowance;\n mapping(uint256 => address) private _token_id_burners;\n\n // Random index\n uint256 private _nonce = 0;\n uint256[TOKEN_LIMIT] private _indices;\n\n constructor() ERC721(\"PalmTreeCollective\", \"PTC\") {}\n\n // General\n function _randomMint(address to) private {\n uint256 randomIndex = uint256(keccak256(abi.encodePacked(_nonce, msg.sender, block.difficulty, block.timestamp)));\n\n _validMint(to, randomIndex);\n }\n\n function _validMint(address to, uint256 index) private {\n uint256 validIndex = _validateIndex(index);\n\n _safeMint(to, validIndex);\n }\n\n function _validateIndex(uint256 index_to_validate) private returns (uint256) {\n uint256 total_size = TOKEN_LIMIT - totalSupply();\n uint256 index = index_to_validate % total_size;\n uint256 value = 0;\n\n if(_indices[index] != 0) {\n value = _indices[index];\n }\n else {\n value = index;\n }\n\n if(_indices[total_size - 1] == 0) {\n _indices[index] = total_size - 1;\n }\n else {\n _indices[index] = _indices[total_size - 1];\n }\n\n _nonce++;\n\n return value;\n }\n\n function _baseURI() internal view override returns (string memory) {\n return baseURI;\n }\n\n function listTokensForOwner(address owner) external view returns (uint256[] memory) {\n uint256 token_count = balanceOf(owner);\n uint256[] memory result = new uint256[](token_count);\n uint256 index;\n\n for(index = 0; index < token_count; index++) {\n result[index] = tokenOfOwnerByIndex(owner, index);\n }\n\n return result;\n }\n\n // Presale eligible\n function isTierTwoPresaleEligible(address minter) external view returns(bool) {\n return _presale_allowance[minter] > 0;\n }\n\n function isTierOnePresaleEligible(address minter) external view returns(bool) {\n return _presale_allowance[minter] > 1;\n }\n\n function presaleAllowanceForAddress(address minter) external view returns(uint) {\n return _presale_allowance[minter];\n }\n\n // Minting\n function mintTokens(address recipient, uint256 num_tokens) external payable nonReentrant {\n require(sale_state != 0, \"Sale is closed\");\n require(num_tokens > 0 && num_tokens <= MAX_MINT_QUANTITY, \"You can only mint 1 to 5 tokens at a time\");\n\n if(sale_state == 3) {\n // Open sale\n require(totalSupply() + num_tokens <= TOKEN_LIMIT, \"Palm Tree Collective has sold out\");\n }\n else {\n require(totalSupply() + num_tokens <= PRESALE_MINT_LIMIT, \"The maximum presale tokens have been minted\");\n\n if(sale_state == 2) {\n // Tier 2 presale\n require(_presale_allowance[recipient] > 0, \"You are not eligible to presale mint\");\n }\n else if(sale_state == 1) {\n // Tier 1 presale\n require(_presale_allowance[recipient] - num_tokens >= 1, \"You cannot mint that many tokens at this time\");\n _presale_allowance[recipient] -= num_tokens;\n }\n }\n\n if(msg.sender != _PT_WALLET) {\n uint256 total_price = mint_price * num_tokens;\n require(msg.value >= total_price, \"Ether value sent too low\");\n }\n\n for(uint256 i = 0; i < num_tokens; i++) {\n _randomMint(recipient);\n }\n }\n\n // Burning\n function burn(uint256 token_id) external {\n require(burn_active, \"You cannot burn at this time\");\n require(ownerOf(token_id) == msg.sender, \"You cannot burn a token you do not own\");\n\n _burn(token_id);\n _token_id_burners[token_id] = msg.sender;\n\n emit Burn(token_id, msg.sender);\n }\n\n function burnerOf(uint256 token_id) external view returns (address) {\n return _token_id_burners[token_id];\n }\n\n // Owner only\n function setProvenanceHash(string calldata provenanceHash) external onlyOwner {\n PROVENANCE_HASH = provenanceHash;\n }\n\n function editPresaleAllowance(address[] memory addresses, uint256 amount) public onlyOwner {\n for(uint256 i; i < addresses.length; i++){\n _presale_allowance[addresses[i]] = amount;\n }\n }\n\n function setBaseURI(string calldata baseURI_) external onlyOwner {\n baseURI = baseURI_;\n }\n\n function reserveTokens(uint256[] calldata tokens) external onlyOwner {\n require(sale_state == 0, \"Sale is not in closed state\");\n require(totalSupply() + tokens.length <= _GIVEAWAY_LIMIT, \"Exceeded giveaway supply\");\n\n for (uint256 i = 0; i < tokens.length; i++) {\n _validMint(_PT_WALLET, tokens[i]);\n }\n }\n\n function setMintPrice(uint256 new_mint_price) external onlyOwner {\n mint_price = new_mint_price;\n }\n\n function setSaleState(uint256 new_state) external onlyOwner {\n sale_state = new_state;\n }\n\n function toggleBurnState() external onlyOwner {\n burn_active = !burn_active;\n }\n\n function withdraw() external onlyOwner {\n uint256 full_balance = (address(this).balance * 100) / 100; // 100%\n// uint256 tenPercentOfBalance = (address(this).balance * 10) / 100; // 10.0%\n\n _PT_WALLET.transfer(full_balance);\n }\n}"
},
"@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol": {
"content": "// SPDX-License-Identifier: MIT\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/access/Ownable.sol": {
"content": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"../utils/Context.sol\";\n\n/**\n * @dev Contract module which provides a basic access control mechanism, where\n * there is an account (an owner) that can be granted exclusive access to\n * specific functions.\n *\n * By default, the owner account will be the one that deploys the contract. This\n * can later be changed with {transferOwnership}.\n *\n * This module is used through inheritance. It will make available the modifier\n * `onlyOwner`, which can be applied to your functions to restrict their use to\n * the owner.\n */\nabstract contract Ownable is Context {\n address private _owner;\n\n event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);\n\n /**\n * @dev Initializes the contract setting the deployer as the initial owner.\n */\n constructor() {\n _setOwner(_msgSender());\n }\n\n /**\n * @dev Returns the address of the current owner.\n */\n function owner() public view virtual returns (address) {\n return _owner;\n }\n\n /**\n * @dev Throws if called by any account other than the owner.\n */\n modifier onlyOwner() {\n require(owner() == _msgSender(), \"Ownable: caller is not the owner\");\n _;\n }\n\n /**\n * @dev Leaves the contract without owner. It will not be possible to call\n * `onlyOwner` functions anymore. Can only be called by the current owner.\n *\n * NOTE: Renouncing ownership will leave the contract without an owner,\n * thereby removing any functionality that is only available to the owner.\n */\n function renounceOwnership() public virtual onlyOwner {\n _setOwner(address(0));\n }\n\n /**\n * @dev Transfers ownership of the contract to a new account (`newOwner`).\n * Can only be called by the current owner.\n */\n function transferOwnership(address newOwner) public virtual onlyOwner {\n require(newOwner != address(0), \"Ownable: new owner is the zero address\");\n _setOwner(newOwner);\n }\n\n function _setOwner(address newOwner) private {\n address oldOwner = _owner;\n _owner = newOwner;\n emit OwnershipTransferred(oldOwner, newOwner);\n }\n}\n"
},
"@openzeppelin/contracts/security/ReentrancyGuard.sol": {
"content": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Contract module that helps prevent reentrant calls to a function.\n *\n * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier\n * available, which can be applied to functions to make sure there are no nested\n * (reentrant) calls to them.\n *\n * Note that because there is a single `nonReentrant` guard, functions marked as\n * `nonReentrant` may not call one another. This can be worked around by making\n * those functions `private`, and then adding `external` `nonReentrant` entry\n * points to them.\n *\n * TIP: If you would like to learn more about reentrancy and alternative ways\n * to protect against it, check out our blog post\n * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].\n */\nabstract contract ReentrancyGuard {\n // Booleans are more expensive than uint256 or any type that takes up a full\n // word because each write operation emits an extra SLOAD to first read the\n // slot's contents, replace the bits taken up by the boolean, and then write\n // back. This is the compiler's defense against contract upgrades and\n // pointer aliasing, and it cannot be disabled.\n\n // The values being non-zero value makes deployment a bit more expensive,\n // but in exchange the refund on every call to nonReentrant will be lower in\n // amount. Since refunds are capped to a percentage of the total\n // transaction's gas, it is best to keep them low in cases like this one, to\n // increase the likelihood of the full refund coming into effect.\n uint256 private constant _NOT_ENTERED = 1;\n uint256 private constant _ENTERED = 2;\n\n uint256 private _status;\n\n constructor() {\n _status = _NOT_ENTERED;\n }\n\n /**\n * @dev Prevents a contract from calling itself, directly or indirectly.\n * Calling a `nonReentrant` function from another `nonReentrant`\n * function is not supported. It is possible to prevent this from happening\n * by making the `nonReentrant` function external, and make it call a\n * `private` function that does the actual work.\n */\n modifier nonReentrant() {\n // On the first call to nonReentrant, _notEntered will be true\n require(_status != _ENTERED, \"ReentrancyGuard: reentrant call\");\n\n // Any calls to nonReentrant after this point will fail\n _status = _ENTERED;\n\n _;\n\n // By storing the original value once again, a refund is triggered (see\n // https://eips.ethereum.org/EIPS/eip-2200)\n _status = _NOT_ENTERED;\n }\n}\n"
},
"@openzeppelin/contracts/token/ERC721/ERC721.sol": {
"content": "// SPDX-License-Identifier: MIT\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: balance query for the zero address\");\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: owner query for nonexistent token\");\n return owner;\n }\n\n /**\n * @dev See {IERC721Metadata-name}.\n */\n function name() public view virtual override returns (string memory) {\n return _name;\n }\n\n /**\n * @dev See {IERC721Metadata-symbol}.\n */\n function symbol() public view virtual override returns (string memory) {\n return _symbol;\n }\n\n /**\n * @dev See {IERC721Metadata-tokenURI}.\n */\n function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {\n require(_exists(tokenId), \"ERC721Metadata: URI query for nonexistent token\");\n\n string memory baseURI = _baseURI();\n return bytes(baseURI).length > 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : \"\";\n }\n\n /**\n * @dev Base URI for computing {tokenURI}. If set, the resulting URI for each\n * token will be the concatenation of the `baseURI` and the `tokenId`. Empty\n * by default, can be overriden in child contracts.\n */\n function _baseURI() internal view virtual returns (string memory) {\n return \"\";\n }\n\n /**\n * @dev See {IERC721-approve}.\n */\n function approve(address to, uint256 tokenId) public 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 owner nor approved for all\"\n );\n\n _approve(to, tokenId);\n }\n\n /**\n * @dev See {IERC721-getApproved}.\n */\n function getApproved(uint256 tokenId) public view virtual override returns (address) {\n require(_exists(tokenId), \"ERC721: approved query for nonexistent token\");\n\n return _tokenApprovals[tokenId];\n }\n\n /**\n * @dev See {IERC721-setApprovalForAll}.\n */\n function setApprovalForAll(address operator, bool approved) public virtual override {\n require(operator != _msgSender(), \"ERC721: approve to caller\");\n\n _operatorApprovals[_msgSender()][operator] = approved;\n emit ApprovalForAll(_msgSender(), operator, approved);\n }\n\n /**\n * @dev See {IERC721-isApprovedForAll}.\n */\n function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {\n return _operatorApprovals[owner][operator];\n }\n\n /**\n * @dev See {IERC721-transferFrom}.\n */\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: transfer caller is not owner nor approved\");\n\n _transfer(from, to, tokenId);\n }\n\n /**\n * @dev See {IERC721-safeTransferFrom}.\n */\n function safeTransferFrom(\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: transfer caller is not owner nor approved\");\n _safeTransfer(from, to, tokenId, _data);\n }\n\n /**\n * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients\n * are aware of the ERC721 protocol to prevent tokens from being forever locked.\n *\n * `_data` is additional data, it has no specified format and it is sent in call to `to`.\n *\n * This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.\n * implement alternative mechanisms to perform token transfer, such as signature-based.\n *\n * Requirements:\n *\n * - `from` cannot be the zero address.\n * - `to` cannot be the zero address.\n * - `tokenId` token must exist and be owned by `from`.\n * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.\n *\n * Emits a {Transfer} event.\n */\n function _safeTransfer(\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 require(_exists(tokenId), \"ERC721: operator query for nonexistent token\");\n address owner = ERC721.ownerOf(tokenId);\n return (spender == owner || getApproved(tokenId) == spender || isApprovedForAll(owner, spender));\n }\n\n /**\n * @dev Safely mints `tokenId` and transfers it to `to`.\n *\n * Requirements:\n *\n * - `tokenId` must not exist.\n * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.\n *\n * Emits a {Transfer} event.\n */\n function _safeMint(address to, uint256 tokenId) internal virtual {\n _safeMint(to, tokenId, \"\");\n }\n\n /**\n * @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is\n * forwarded in {IERC721Receiver-onERC721Received} to contract recipients.\n */\n function _safeMint(\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\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\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 of token that is not own\");\n require(to != address(0), \"ERC721: transfer to the zero address\");\n\n _beforeTokenTransfer(from, to, tokenId);\n\n // Clear approvals from the previous owner\n _approve(address(0), tokenId);\n\n _balances[from] -= 1;\n _balances[to] += 1;\n _owners[tokenId] = to;\n\n emit Transfer(from, to, tokenId);\n }\n\n /**\n * @dev Approve `to` to operate on `tokenId`\n *\n * Emits a {Approval} event.\n */\n function _approve(address to, uint256 tokenId) internal virtual {\n _tokenApprovals[tokenId] = to;\n emit Approval(ERC721.ownerOf(tokenId), to, tokenId);\n }\n\n /**\n * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.\n * The call is not executed if the target address is not a contract.\n *\n * @param from address representing the previous owner of the given token ID\n * @param to target address that will receive the tokens\n * @param tokenId uint256 ID of the token to be transferred\n * @param _data bytes optional data to send along with the call\n * @return bool whether the call correctly returned the expected magic value\n */\n function _checkOnERC721Received(\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(to).onERC721Received.selector;\n } catch (bytes memory reason) {\n if (reason.length == 0) {\n revert(\"ERC721: transfer to non ERC721Receiver implementer\");\n } else {\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"
},
"@openzeppelin/contracts/token/ERC721/extensions/IERC721Enumerable.sol": {
"content": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"../IERC721.sol\";\n\n/**\n * @title ERC-721 Non-Fungible Token Standard, optional enumeration extension\n * @dev See https://eips.ethereum.org/EIPS/eip-721\n */\ninterface IERC721Enumerable is IERC721 {\n /**\n * @dev Returns the total amount of tokens stored by the contract.\n */\n function totalSupply() external view returns (uint256);\n\n /**\n * @dev Returns a token ID owned by `owner` at a given `index` of its token list.\n * Use along with {balanceOf} to enumerate all of ``owner``'s tokens.\n */\n function tokenOfOwnerByIndex(address owner, uint256 index) external view returns (uint256 tokenId);\n\n /**\n * @dev Returns a token ID at a given `index` of all the tokens stored by the contract.\n * Use along with {totalSupply} to enumerate all tokens.\n */\n function tokenByIndex(uint256 index) external view returns (uint256);\n}\n"
},
"@openzeppelin/contracts/token/ERC721/IERC721.sol": {
"content": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"../../utils/introspection/IERC165.sol\";\n\n/**\n * @dev Required interface of an ERC721 compliant contract.\n */\ninterface IERC721 is IERC165 {\n /**\n * @dev Emitted when `tokenId` token is transferred from `from` to `to`.\n */\n event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);\n\n /**\n * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.\n */\n event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);\n\n /**\n * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.\n */\n event ApprovalForAll(address indexed owner, address indexed operator, bool approved);\n\n /**\n * @dev Returns the number of tokens in ``owner``'s account.\n */\n function balanceOf(address owner) external view returns (uint256 balance);\n\n /**\n * @dev Returns the owner of the `tokenId` token.\n *\n * Requirements:\n *\n * - `tokenId` must exist.\n */\n function ownerOf(uint256 tokenId) external view returns (address owner);\n\n /**\n * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients\n * are aware of the ERC721 protocol to prevent tokens from being forever locked.\n *\n * Requirements:\n *\n * - `from` cannot be the zero address.\n * - `to` cannot be the zero address.\n * - `tokenId` token must exist and be owned by `from`.\n * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.\n * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.\n *\n * Emits a {Transfer} event.\n */\n function safeTransferFrom(\n address from,\n address to,\n uint256 tokenId\n ) external;\n\n /**\n * @dev Transfers `tokenId` token from `from` to `to`.\n *\n * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.\n *\n * Requirements:\n *\n * - `from` cannot be the zero address.\n * - `to` cannot be the zero address.\n * - `tokenId` token must be owned by `from`.\n * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.\n *\n * Emits a {Transfer} event.\n */\n function transferFrom(\n address from,\n address to,\n uint256 tokenId\n ) external;\n\n /**\n * @dev Gives permission to `to` to transfer `tokenId` token to another account.\n * The approval is cleared when the token is transferred.\n *\n * Only a single account can be approved at a time, so approving the zero address clears previous approvals.\n *\n * Requirements:\n *\n * - The caller must own the token or be an approved operator.\n * - `tokenId` must exist.\n *\n * Emits an {Approval} event.\n */\n function approve(address to, uint256 tokenId) external;\n\n /**\n * @dev Returns the account approved for `tokenId` token.\n *\n * Requirements:\n *\n * - `tokenId` must exist.\n */\n function getApproved(uint256 tokenId) external view returns (address operator);\n\n /**\n * @dev Approve or remove `operator` as an operator for the caller.\n * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.\n *\n * Requirements:\n *\n * - The `operator` cannot be the caller.\n *\n * Emits an {ApprovalForAll} event.\n */\n function setApprovalForAll(address operator, bool _approved) external;\n\n /**\n * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.\n *\n * See {setApprovalForAll}\n */\n function isApprovedForAll(address owner, address operator) external view returns (bool);\n\n /**\n * @dev Safely transfers `tokenId` token from `from` to `to`.\n *\n * Requirements:\n *\n * - `from` cannot be the zero address.\n * - `to` cannot be the zero address.\n * - `tokenId` token must exist and be owned by `from`.\n * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.\n * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.\n *\n * Emits a {Transfer} event.\n */\n function safeTransferFrom(\n address from,\n address to,\n uint256 tokenId,\n bytes calldata data\n ) external;\n}\n"
},
"@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol": {
"content": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\n/**\n * @title ERC721 token receiver interface\n * @dev Interface for any contract that wants to support safeTransfers\n * from ERC721 asset contracts.\n */\ninterface IERC721Receiver {\n /**\n * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}\n * by `operator` from `from`, this function is called.\n *\n * It must return its Solidity selector to confirm the token transfer.\n * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.\n *\n * The selector can be obtained in Solidity with `IERC721.onERC721Received.selector`.\n */\n function onERC721Received(\n address operator,\n address from,\n uint256 tokenId,\n bytes calldata data\n ) external returns (bytes4);\n}\n"
},
"@openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol": {
"content": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"../IERC721.sol\";\n\n/**\n * @title ERC-721 Non-Fungible Token Standard, optional metadata extension\n * @dev See https://eips.ethereum.org/EIPS/eip-721\n */\ninterface IERC721Metadata is IERC721 {\n /**\n * @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/Address.sol": {
"content": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Collection of functions related to the address type\n */\nlibrary Address {\n /**\n * @dev Returns true if `account` is a contract.\n *\n * [IMPORTANT]\n * ====\n * It is unsafe to assume that an address for which this function returns\n * false is an externally-owned account (EOA) and not a contract.\n *\n * Among others, `isContract` will return false for the following\n * types of addresses:\n *\n * - an externally-owned account\n * - a contract in construction\n * - an address where a contract will be created\n * - an address where a contract lived, but was destroyed\n * ====\n */\n function isContract(address account) internal view returns (bool) {\n // This method relies on extcodesize, which returns 0 for contracts in\n // construction, since the code is only stored at the end of the\n // constructor execution.\n\n uint256 size;\n assembly {\n size := extcodesize(account)\n }\n return size > 0;\n }\n\n /**\n * @dev Replacement for Solidity's `transfer`: sends `amount` wei to\n * `recipient`, forwarding all available gas and reverting on errors.\n *\n * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost\n * of certain opcodes, possibly making contracts go over the 2300 gas limit\n * imposed by `transfer`, making them unable to receive funds via\n * `transfer`. {sendValue} removes this limitation.\n *\n * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].\n *\n * IMPORTANT: because control is transferred to `recipient`, care must be\n * taken to not create reentrancy vulnerabilities. Consider using\n * {ReentrancyGuard} or the\n * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].\n */\n function sendValue(address payable recipient, uint256 amount) internal {\n require(address(this).balance >= amount, \"Address: insufficient balance\");\n\n (bool success, ) = recipient.call{value: amount}(\"\");\n require(success, \"Address: unable to send value, recipient may have reverted\");\n }\n\n /**\n * @dev Performs a Solidity function call using a low level `call`. A\n * plain `call` is an unsafe replacement for a function call: use this\n * function instead.\n *\n * If `target` reverts with a revert reason, it is bubbled up by this\n * function (like regular Solidity function calls).\n *\n * Returns the raw returned data. To convert to the expected return value,\n * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].\n *\n * Requirements:\n *\n * - `target` must be a contract.\n * - calling `target` with `data` must not revert.\n *\n * _Available since v3.1._\n */\n function functionCall(address target, bytes memory data) internal returns (bytes memory) {\n return functionCall(target, data, \"Address: low-level call failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with\n * `errorMessage` as a fallback revert reason when `target` reverts.\n *\n * _Available since v3.1._\n */\n function functionCall(\n address target,\n bytes memory data,\n string memory errorMessage\n ) internal returns (bytes memory) {\n return functionCallWithValue(target, data, 0, errorMessage);\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n * but also transferring `value` wei to `target`.\n *\n * Requirements:\n *\n * - the calling contract must have an ETH balance of at least `value`.\n * - the called Solidity function must be `payable`.\n *\n * _Available since v3.1._\n */\n function functionCallWithValue(\n address target,\n bytes memory data,\n uint256 value\n ) internal returns (bytes memory) {\n return functionCallWithValue(target, data, value, \"Address: low-level call with value failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but\n * with `errorMessage` as a fallback revert reason when `target` reverts.\n *\n * _Available since v3.1._\n */\n function functionCallWithValue(\n address target,\n bytes memory data,\n uint256 value,\n string memory errorMessage\n ) internal returns (bytes memory) {\n require(address(this).balance >= value, \"Address: insufficient balance for call\");\n require(isContract(target), \"Address: call to non-contract\");\n\n (bool success, bytes memory returndata) = target.call{value: value}(data);\n return _verifyCallResult(success, returndata, errorMessage);\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n * but performing a static call.\n *\n * _Available since v3.3._\n */\n function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {\n return functionStaticCall(target, data, \"Address: low-level static call failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n * but performing a static call.\n *\n * _Available since v3.3._\n */\n function functionStaticCall(\n address target,\n bytes memory data,\n string memory errorMessage\n ) internal view returns (bytes memory) {\n require(isContract(target), \"Address: static call to non-contract\");\n\n (bool success, bytes memory returndata) = target.staticcall(data);\n return _verifyCallResult(success, returndata, errorMessage);\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n * but performing a delegate call.\n *\n * _Available since v3.4._\n */\n function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {\n return functionDelegateCall(target, data, \"Address: low-level delegate call failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n * but performing a delegate call.\n *\n * _Available since v3.4._\n */\n function functionDelegateCall(\n address target,\n bytes memory data,\n string memory errorMessage\n ) internal returns (bytes memory) {\n require(isContract(target), \"Address: delegate call to non-contract\");\n\n (bool success, bytes memory returndata) = target.delegatecall(data);\n return _verifyCallResult(success, returndata, errorMessage);\n }\n\n function _verifyCallResult(\n bool success,\n bytes memory returndata,\n string memory errorMessage\n ) private pure returns (bytes memory) {\n if (success) {\n return returndata;\n } else {\n // Look for revert reason and bubble it up if present\n if (returndata.length > 0) {\n // The easiest way to bubble the revert reason is using memory via assembly\n\n 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/utils/Context.sol": {
"content": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\n/*\n * @dev Provides information about the current execution context, including the\n * sender of the transaction and its data. While these are generally available\n * via msg.sender and msg.data, they should not be accessed in such a direct\n * manner, since when dealing with meta-transactions the account sending and\n * paying for execution may not be the actual sender (as far as an application\n * is concerned).\n *\n * This contract is only required for intermediate, library-like contracts.\n */\nabstract contract Context {\n function _msgSender() internal view virtual returns (address) {\n return msg.sender;\n }\n\n function _msgData() internal view virtual returns (bytes calldata) {\n return msg.data;\n }\n}\n"
},
"@openzeppelin/contracts/utils/Strings.sol": {
"content": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\n/**\n * @dev String operations.\n */\nlibrary Strings {\n bytes16 private constant _HEX_SYMBOLS = \"0123456789abcdef\";\n\n /**\n * @dev Converts a `uint256` to its ASCII `string` decimal representation.\n */\n function toString(uint256 value) internal pure returns (string memory) {\n // Inspired by OraclizeAPI's implementation - MIT licence\n // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol\n\n if (value == 0) {\n return \"0\";\n }\n uint256 temp = value;\n uint256 digits;\n while (temp != 0) {\n digits++;\n temp /= 10;\n }\n bytes memory buffer = new bytes(digits);\n while (value != 0) {\n digits -= 1;\n buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));\n value /= 10;\n }\n return string(buffer);\n }\n\n /**\n * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.\n */\n function toHexString(uint256 value) internal pure returns (string memory) {\n if (value == 0) {\n return \"0x00\";\n }\n uint256 temp = value;\n uint256 length = 0;\n while (temp != 0) {\n length++;\n temp >>= 8;\n }\n return toHexString(value, length);\n }\n\n /**\n * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.\n */\n function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {\n bytes memory buffer = new bytes(2 * length + 2);\n buffer[0] = \"0\";\n buffer[1] = \"x\";\n for (uint256 i = 2 * length + 1; i > 1; --i) {\n buffer[i] = _HEX_SYMBOLS[value & 0xf];\n value >>= 4;\n }\n require(value == 0, \"Strings: hex length insufficient\");\n return string(buffer);\n }\n}\n"
},
"@openzeppelin/contracts/utils/introspection/ERC165.sol": {
"content": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"./IERC165.sol\";\n\n/**\n * @dev Implementation of the {IERC165} interface.\n *\n * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check\n * for the additional interface id that will be supported. For example:\n *\n * ```solidity\n * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {\n * return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);\n * }\n * ```\n *\n * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.\n */\nabstract contract ERC165 is IERC165 {\n /**\n * @dev See {IERC165-supportsInterface}.\n */\n function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {\n return interfaceId == type(IERC165).interfaceId;\n }\n}\n"
},
"@openzeppelin/contracts/utils/introspection/IERC165.sol": {
"content": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Interface of the ERC165 standard, as defined in the\n * https://eips.ethereum.org/EIPS/eip-165[EIP].\n *\n * Implementers can declare support of contract interfaces, which can then be\n * queried by others ({ERC165Checker}).\n *\n * For an implementation, see {ERC165}.\n */\ninterface IERC165 {\n /**\n * @dev Returns true if this contract implements the interface defined by\n * `interfaceId`. See the corresponding\n * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]\n * to learn more about how these ids are created.\n *\n * This function call must use less than 30 000 gas.\n */\n function supportsInterface(bytes4 interfaceId) external view returns (bool);\n}\n"
}
},
"settings": {
"optimizer": {
"enabled": false,
"runs": 200
},
"outputSelection": {
"*": {
"*": [
"evm.bytecode",
"evm.deployedBytecode",
"devdoc",
"userdoc",
"metadata",
"abi"
]
}
},
"libraries": {}
}
}