Transaction Hash:
Block:
12859049 at Jul-19-2021 08:03:32 PM +UTC
Transaction Fee:
0.00353956 ETH
$8.66
Gas Used:
176,978 Gas / 20 Gwei
Emitted Events:
262 |
NFT_FM.TransferSingle( operator=[Receiver] FlatPriceSale, from=[Receiver] FlatPriceSale, to=[Sender] 0x18c6a47aca1c6a237e53ed2fc3a8fb392c97169b, id=8, value=1 )
|
263 |
FlatPriceSale.Buy( saleId=28, nftID=8, quantity=1, account=[Sender] 0x18c6a47aca1c6a237e53ed2fc3a8fb392c97169b )
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Account State Difference:
Address | Before | After | State Difference | ||
---|---|---|---|---|---|
0x18C6A47A...92c97169b | (Fake_Phishing1197600) |
5.994503471673595797 Eth
Nonce: 1317
|
5.988463911673595797 Eth
Nonce: 1318
| 0.00603956 | |
0x45a36a8e...e579E11E2
Miner
| (AntPool 2) | 1,451.520760246172778563 Eth | 1,451.524299806172778563 Eth | 0.00353956 | |
0x82Cb2305...f58466659 | 0.250846631752041305 Eth | 0.253221631752041305 Eth | 0.002375 | ||
0x88d3e00c...b50D608B7 | |||||
0xb46700fB...eff32D40f | |||||
0xc8949298...9A38D339a | (NFT FM: Deployer) | 1.018624308363530323 Eth | 1.018749308363530323 Eth | 0.000125 |
Execution Trace
ETH 0.0025
FlatPriceSale.buyNFT( nftID=8, quantity=1 )
- ETH 0.002375
0x82cb2305388c853ecfe9ea83a1604acf58466659.CALL( )
- ETH 0.000125
NFT FM: Deployer.CALL( )
-
NFT_FM.safeTransferFrom( from=0xb46700fBE3C2ed36851A4ccFeAD109ceff32D40f, to=0x18C6A47AcA1c6a237e53eD2fc3a8fB392c97169b, id=8, amount=1, data=0x )
File 1 of 2: FlatPriceSale
File 2 of 2: NFT_FM
{"Address.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Collection of functions related to the address type\n */\nlibrary Address {\n /**\n * @dev Returns true if `account` is a contract.\n *\n * [IMPORTANT]\n * ====\n * It is unsafe to assume that an address for which this function returns\n * false is an externally-owned account (EOA) and not a contract.\n *\n * Among others, `isContract` will return false for the following\n * types of addresses:\n *\n * - an externally-owned account\n * - a contract in construction\n * - an address where a contract will be created\n * - an address where a contract lived, but was destroyed\n * ====\n */\n function isContract(address account) internal view returns (bool) {\n // This method relies on extcodesize, which returns 0 for contracts in\n // construction, since the code is only stored at the end of the\n // constructor execution.\n\n uint256 size;\n // solhint-disable-next-line no-inline-assembly\n assembly { size := extcodesize(account) }\n return size \u003e 0;\n }\n\n /**\n * @dev Replacement for Solidity\u0027s `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 \u003e= amount, \"Address: insufficient balance\");\n\n // solhint-disable-next-line avoid-low-level-calls, avoid-call-value\n (bool success, ) = recipient.call{ value: amount }(\"\");\n require(success, \"Address: unable to send value, recipient may have reverted\");\n }\n\n /**\n * @dev Performs a Solidity function call using a low level `call`. A\n * plain`call` is an unsafe replacement for a function call: use this\n * function instead.\n *\n * If `target` reverts with a revert reason, it is bubbled up by this\n * function (like regular Solidity function calls).\n *\n * Returns the raw returned data. To convert to the expected return value,\n * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].\n *\n * Requirements:\n *\n * - `target` must be a contract.\n * - calling `target` with `data` must not revert.\n *\n * _Available since v3.1._\n */\n function functionCall(address target, bytes memory data) internal returns (bytes memory) {\n return functionCall(target, data, \"Address: low-level call failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with\n * `errorMessage` as a fallback revert reason when `target` reverts.\n *\n * _Available since v3.1._\n */\n function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {\n return functionCallWithValue(target, data, 0, errorMessage);\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n * but also transferring `value` wei to `target`.\n *\n * Requirements:\n *\n * - the calling contract must have an ETH balance of at least `value`.\n * - the called Solidity function must be `payable`.\n *\n * _Available since v3.1._\n */\n function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {\n return functionCallWithValue(target, data, value, \"Address: low-level call with value failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but\n * with `errorMessage` as a fallback revert reason when `target` reverts.\n *\n * _Available since v3.1._\n */\n function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {\n require(address(this).balance \u003e= value, \"Address: insufficient balance for call\");\n require(isContract(target), \"Address: call to non-contract\");\n\n // solhint-disable-next-line avoid-low-level-calls\n (bool success, bytes memory returndata) = target.call{ value: value }(data);\n return _verifyCallResult(success, returndata, errorMessage);\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n * but performing a static call.\n *\n * _Available since v3.3._\n */\n function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {\n return functionStaticCall(target, data, \"Address: low-level static call failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n * but performing a static call.\n *\n * _Available since v3.3._\n */\n function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {\n require(isContract(target), \"Address: static call to non-contract\");\n\n // solhint-disable-next-line avoid-low-level-calls\n (bool success, bytes memory returndata) = target.staticcall(data);\n return _verifyCallResult(success, returndata, errorMessage);\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n * but performing a delegate call.\n *\n * _Available since v3.4._\n */\n function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {\n return functionDelegateCall(target, data, \"Address: low-level delegate call failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n * but performing a delegate call.\n *\n * _Available since v3.4._\n */\n function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {\n require(isContract(target), \"Address: delegate call to non-contract\");\n\n // solhint-disable-next-line avoid-low-level-calls\n (bool success, bytes memory returndata) = target.delegatecall(data);\n return _verifyCallResult(success, returndata, errorMessage);\n }\n\n function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {\n if (success) {\n return returndata;\n } else {\n // Look for revert reason and bubble it up if present\n if (returndata.length \u003e 0) {\n // The easiest way to bubble the revert reason is using memory via assembly\n\n // solhint-disable-next-line no-inline-assembly\n assembly {\n let returndata_size := mload(returndata)\n revert(add(32, returndata), returndata_size)\n }\n } else {\n revert(errorMessage);\n }\n }\n }\n}\n"},"Context.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\n/*\n * @dev Provides information about the current execution context, including the\n * sender of the transaction and its data. While these are generally available\n * via msg.sender and msg.data, they should not be accessed in such a direct\n * manner, since when dealing with meta-transactions the account sending and\n * paying for execution may not be the actual sender (as far as an application\n * is concerned).\n *\n * This contract is only required for intermediate, library-like contracts.\n */\nabstract contract Context {\n function _msgSender() internal view virtual returns (address) {\n return msg.sender;\n }\n\n function _msgData() internal view virtual returns (bytes calldata) {\n this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691\n return msg.data;\n }\n}\n"},"ERC1155.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"./IERC1155.sol\";\nimport \"./IERC1155Receiver.sol\";\nimport \"./IERC1155MetadataURI.sol\";\nimport \"./Address.sol\";\nimport \"./Context.sol\";\nimport \"./ERC165.sol\";\n\n/**\n *\n * @dev Implementation of the basic standard multi-token.\n * See https://eips.ethereum.org/EIPS/eip-1155\n * Originally based on code by Enjin: https://github.com/enjin/erc-1155\n *\n * _Available since v3.1._\n */\ncontract ERC1155 is Context, ERC165, IERC1155, IERC1155MetadataURI {\n using Address for address;\n\n // Mapping from token ID to account balances\n mapping (uint256 =\u003e mapping(address =\u003e uint256)) private _balances;\n\n // Mapping from account to operator approvals\n mapping (address =\u003e mapping(address =\u003e bool)) private _operatorApprovals;\n\n // Used as the URI for all token types by relying on ID substitution, e.g. https://token-cdn-domain/{id}.json\n string private _uri;\n\n /**\n * @dev See {_setURI}.\n */\n constructor (string memory uri_) {\n _setURI(uri_);\n }\n\n /**\n * @dev See {IERC165-supportsInterface}.\n */\n function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {\n return interfaceId == type(IERC1155).interfaceId\n || interfaceId == type(IERC1155MetadataURI).interfaceId\n || super.supportsInterface(interfaceId);\n }\n\n /**\n * @dev See {IERC1155MetadataURI-uri}.\n *\n * This implementation returns the same URI for *all* token types. It relies\n * on the token type ID substitution mechanism\n * https://eips.ethereum.org/EIPS/eip-1155#metadata[defined in the EIP].\n *\n * Clients calling this function must replace the `\\{id\\}` substring with the\n * actual token type ID.\n */\n function uri(uint256) public view virtual override returns (string memory) {\n return _uri;\n }\n\n /**\n * @dev See {IERC1155-balanceOf}.\n *\n * Requirements:\n *\n * - `account` cannot be the zero address.\n */\n function balanceOf(address account, uint256 id) public view virtual override returns (uint256) {\n require(account != address(0), \"ERC1155: balance query for the zero address\");\n return _balances[id][account];\n }\n\n /**\n * @dev See {IERC1155-balanceOfBatch}.\n *\n * Requirements:\n *\n * - `accounts` and `ids` must have the same length.\n */\n function balanceOfBatch(\n address[] memory accounts,\n uint256[] memory ids\n )\n public\n view\n virtual\n override\n returns (uint256[] memory)\n {\n require(accounts.length == ids.length, \"ERC1155: accounts and ids length mismatch\");\n\n uint256[] memory batchBalances = new uint256[](accounts.length);\n\n for (uint256 i = 0; i \u003c accounts.length; ++i) {\n batchBalances[i] = balanceOf(accounts[i], ids[i]);\n }\n\n return batchBalances;\n }\n\n /**\n * @dev See {IERC1155-setApprovalForAll}.\n */\n function setApprovalForAll(address operator, bool approved) public virtual override {\n require(_msgSender() != operator, \"ERC1155: setting approval status for self\");\n\n _operatorApprovals[_msgSender()][operator] = approved;\n emit ApprovalForAll(_msgSender(), operator, approved);\n }\n\n /**\n * @dev See {IERC1155-isApprovedForAll}.\n */\n function isApprovedForAll(address account, address operator) public view virtual override returns (bool) {\n return _operatorApprovals[account][operator];\n }\n\n /**\n * @dev See {IERC1155-safeTransferFrom}.\n */\n function safeTransferFrom(\n address from,\n address to,\n uint256 id,\n uint256 amount,\n bytes memory data\n )\n public\n virtual\n override\n {\n require(\n from == _msgSender() || isApprovedForAll(from, _msgSender()),\n \"ERC1155: caller is not owner nor approved\"\n );\n _safeTransferFrom(from, to, id, amount, data);\n }\n\n /**\n * @dev See {IERC1155-safeBatchTransferFrom}.\n */\n function safeBatchTransferFrom(\n address from,\n address to,\n uint256[] memory ids,\n uint256[] memory amounts,\n bytes memory data\n )\n public\n virtual\n override\n {\n require(\n from == _msgSender() || isApprovedForAll(from, _msgSender()),\n \"ERC1155: transfer caller is not owner nor approved\"\n );\n _safeBatchTransferFrom(from, to, ids, amounts, data);\n }\n\n /**\n * @dev Transfers `amount` tokens of token type `id` from `from` to `to`.\n *\n * Emits a {TransferSingle} event.\n *\n * Requirements:\n *\n * - `to` cannot be the zero address.\n * - `from` must have a balance of tokens of type `id` of at least `amount`.\n * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155Received} and return the\n * acceptance magic value.\n */\n function _safeTransferFrom(\n address from,\n address to,\n uint256 id,\n uint256 amount,\n bytes memory data\n )\n internal\n virtual\n {\n require(to != address(0), \"ERC1155: transfer to the zero address\");\n\n address operator = _msgSender();\n\n _beforeTokenTransfer(operator, from, to, _asSingletonArray(id), _asSingletonArray(amount), data);\n\n uint256 fromBalance = _balances[id][from];\n require(fromBalance \u003e= amount, \"ERC1155: insufficient balance for transfer\");\n _balances[id][from] = fromBalance - amount;\n _balances[id][to] += amount;\n\n emit TransferSingle(operator, from, to, id, amount);\n\n _doSafeTransferAcceptanceCheck(operator, from, to, id, amount, data);\n }\n\n /**\n * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {_safeTransferFrom}.\n *\n * Emits a {TransferBatch} event.\n *\n * Requirements:\n *\n * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155BatchReceived} and return the\n * acceptance magic value.\n */\n function _safeBatchTransferFrom(\n address from,\n address to,\n uint256[] memory ids,\n uint256[] memory amounts,\n bytes memory data\n )\n internal\n virtual\n {\n require(ids.length == amounts.length, \"ERC1155: ids and amounts length mismatch\");\n require(to != address(0), \"ERC1155: transfer to the zero address\");\n\n address operator = _msgSender();\n\n _beforeTokenTransfer(operator, from, to, ids, amounts, data);\n\n for (uint256 i = 0; i \u003c ids.length; ++i) {\n uint256 id = ids[i];\n uint256 amount = amounts[i];\n\n uint256 fromBalance = _balances[id][from];\n require(fromBalance \u003e= amount, \"ERC1155: insufficient balance for transfer\");\n _balances[id][from] = fromBalance - amount;\n _balances[id][to] += amount;\n }\n\n emit TransferBatch(operator, from, to, ids, amounts);\n\n _doSafeBatchTransferAcceptanceCheck(operator, from, to, ids, amounts, data);\n }\n\n /**\n * @dev Sets a new URI for all token types, by relying on the token type ID\n * substitution mechanism\n * https://eips.ethereum.org/EIPS/eip-1155#metadata[defined in the EIP].\n *\n * By this mechanism, any occurrence of the `\\{id\\}` substring in either the\n * URI or any of the amounts in the JSON file at said URI will be replaced by\n * clients with the token type ID.\n *\n * For example, the `https://token-cdn-domain/\\{id\\}.json` URI would be\n * interpreted by clients as\n * `https://token-cdn-domain/000000000000000000000000000000000000000000000000000000000004cce0.json`\n * for token type ID 0x4cce0.\n *\n * See {uri}.\n *\n * Because these URIs cannot be meaningfully represented by the {URI} event,\n * this function emits no events.\n */\n function _setURI(string memory newuri) internal virtual {\n _uri = newuri;\n }\n\n /**\n * @dev Creates `amount` tokens of token type `id`, and assigns them to `account`.\n *\n * Emits a {TransferSingle} event.\n *\n * Requirements:\n *\n * - `account` cannot be the zero address.\n * - If `account` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155Received} and return the\n * acceptance magic value.\n */\n function _mint(address account, uint256 id, uint256 amount, bytes memory data) internal virtual {\n require(account != address(0), \"ERC1155: mint to the zero address\");\n\n address operator = _msgSender();\n\n _beforeTokenTransfer(operator, address(0), account, _asSingletonArray(id), _asSingletonArray(amount), data);\n\n _balances[id][account] += amount;\n emit TransferSingle(operator, address(0), account, id, amount);\n\n _doSafeTransferAcceptanceCheck(operator, address(0), account, id, amount, data);\n }\n\n /**\n * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {_mint}.\n *\n * Requirements:\n *\n * - `ids` and `amounts` must have the same length.\n * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155BatchReceived} and return the\n * acceptance magic value.\n */\n function _mintBatch(address to, uint256[] memory ids, uint256[] memory amounts, bytes memory data) internal virtual {\n require(to != address(0), \"ERC1155: mint to the zero address\");\n require(ids.length == amounts.length, \"ERC1155: ids and amounts length mismatch\");\n\n address operator = _msgSender();\n\n _beforeTokenTransfer(operator, address(0), to, ids, amounts, data);\n\n for (uint i = 0; i \u003c ids.length; i++) {\n _balances[ids[i]][to] += amounts[i];\n }\n\n emit TransferBatch(operator, address(0), to, ids, amounts);\n\n _doSafeBatchTransferAcceptanceCheck(operator, address(0), to, ids, amounts, data);\n }\n\n /**\n * @dev Destroys `amount` tokens of token type `id` from `account`\n *\n * Requirements:\n *\n * - `account` cannot be the zero address.\n * - `account` must have at least `amount` tokens of token type `id`.\n */\n function _burn(address account, uint256 id, uint256 amount) internal virtual {\n require(account != address(0), \"ERC1155: burn from the zero address\");\n\n address operator = _msgSender();\n\n _beforeTokenTransfer(operator, account, address(0), _asSingletonArray(id), _asSingletonArray(amount), \"\");\n\n uint256 accountBalance = _balances[id][account];\n require(accountBalance \u003e= amount, \"ERC1155: burn amount exceeds balance\");\n _balances[id][account] = accountBalance - amount;\n\n emit TransferSingle(operator, account, address(0), id, amount);\n }\n\n /**\n * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {_burn}.\n *\n * Requirements:\n *\n * - `ids` and `amounts` must have the same length.\n */\n function _burnBatch(address account, uint256[] memory ids, uint256[] memory amounts) internal virtual {\n require(account != address(0), \"ERC1155: burn from the zero address\");\n require(ids.length == amounts.length, \"ERC1155: ids and amounts length mismatch\");\n\n address operator = _msgSender();\n\n _beforeTokenTransfer(operator, account, address(0), ids, amounts, \"\");\n\n for (uint i = 0; i \u003c ids.length; i++) {\n uint256 id = ids[i];\n uint256 amount = amounts[i];\n\n uint256 accountBalance = _balances[id][account];\n require(accountBalance \u003e= amount, \"ERC1155: burn amount exceeds balance\");\n _balances[id][account] = accountBalance - amount;\n }\n\n emit TransferBatch(operator, account, address(0), ids, amounts);\n }\n\n /**\n * @dev Hook that is called before any token transfer. This includes minting\n * and burning, as well as batched variants.\n *\n * The same hook is called on both single and batched variants. For single\n * transfers, the length of the `id` and `amount` arrays will be 1.\n *\n * Calling conditions (for each `id` and `amount` pair):\n *\n * - When `from` and `to` are both non-zero, `amount` of ``from``\u0027s tokens\n * of token type `id` will be transferred to `to`.\n * - When `from` is zero, `amount` tokens of token type `id` will be minted\n * for `to`.\n * - when `to` is zero, `amount` of ``from``\u0027s tokens of token type `id`\n * will be burned.\n * - `from` and `to` are never both zero.\n * - `ids` and `amounts` have the same, non-zero length.\n *\n * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].\n */\n function _beforeTokenTransfer(\n address operator,\n address from,\n address to,\n uint256[] memory ids,\n uint256[] memory amounts,\n bytes memory data\n )\n internal\n virtual\n { }\n\n function _doSafeTransferAcceptanceCheck(\n address operator,\n address from,\n address to,\n uint256 id,\n uint256 amount,\n bytes memory data\n )\n private\n {\n if (to.isContract()) {\n try IERC1155Receiver(to).onERC1155Received(operator, from, id, amount, data) returns (bytes4 response) {\n if (response != IERC1155Receiver(to).onERC1155Received.selector) {\n revert(\"ERC1155: ERC1155Receiver rejected tokens\");\n }\n } catch Error(string memory reason) {\n revert(reason);\n } catch {\n revert(\"ERC1155: transfer to non ERC1155Receiver implementer\");\n }\n }\n }\n\n function _doSafeBatchTransferAcceptanceCheck(\n address operator,\n address from,\n address to,\n uint256[] memory ids,\n uint256[] memory amounts,\n bytes memory data\n )\n private\n {\n if (to.isContract()) {\n try IERC1155Receiver(to).onERC1155BatchReceived(operator, from, ids, amounts, data) returns (bytes4 response) {\n if (response != IERC1155Receiver(to).onERC1155BatchReceived.selector) {\n revert(\"ERC1155: ERC1155Receiver rejected tokens\");\n }\n } catch Error(string memory reason) {\n revert(reason);\n } catch {\n revert(\"ERC1155: transfer to non ERC1155Receiver implementer\");\n }\n }\n }\n\n function _asSingletonArray(uint256 element) private pure returns (uint256[] memory) {\n uint256[] memory array = new uint256[](1);\n array[0] = element;\n\n return array;\n }\n}\n"},"ERC1155Holder.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"./ERC1155Receiver.sol\";\n\n/**\n * @dev _Available since v3.1._\n */\ncontract ERC1155Holder is ERC1155Receiver {\n function onERC1155Received(address, address, uint256, uint256, bytes memory) public virtual override returns (bytes4) {\n return this.onERC1155Received.selector;\n }\n\n function onERC1155BatchReceived(address, address, uint256[] memory, uint256[] memory, bytes memory) public virtual override returns (bytes4) {\n return this.onERC1155BatchReceived.selector;\n }\n}\n"},"ERC1155Receiver.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"./IERC1155Receiver.sol\";\nimport \"./ERC165.sol\";\n\n/**\n * @dev _Available since v3.1._\n */\nabstract contract ERC1155Receiver is ERC165, IERC1155Receiver {\n /**\n * @dev See {IERC165-supportsInterface}.\n */\n function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {\n return interfaceId == type(IERC1155Receiver).interfaceId\n || super.supportsInterface(interfaceId);\n }\n}\n"},"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}"},"FlatPriceSale.sol":{"content":"// SPDX-License-Identifier: MIT\n\nimport \"./Context.sol\";\nimport \"./SafeMath.sol\";\nimport \"./Ownable.sol\";\nimport \"./IERC20.sol\";\nimport \"./IERC1155.sol\";\nimport \"./ReentrancyGuard.sol\";\nimport \"./ERC1155Holder.sol\";\nimport \"./INFTSale.sol\";\n\npragma solidity 0.8.4;\n\ncontract FlatPriceSale is Context, Ownable, ReentrancyGuard, ERC1155Holder, INFTSale {\n using SafeMath for uint256;\n\n constructor(address nftToken, address payable _authAddress) {\n NFT_TOKEN = IERC1155(nftToken);\n nftAddress = nftToken;\n authAddress = _authAddress;\n }\n\n event Buy(\n uint256 indexed saleId,\n uint256 nftID,\n uint256 quantity,\n address indexed account\n );\n\n address payable public authAddress;\n address public nftAddress;\n IERC1155 private NFT_TOKEN;\n\n struct NFTSetSale {\n uint32 saleId;\n uint256 timestamp;\n address buyer;\n }\n\n mapping(uint32 =\u003e NFTSetSale) public sales;\n uint32 public totalSales;\n\n struct NFTSet {\n address payable artist;\n uint256 startTime;\n uint32 quantity;\n uint32 sold;\n uint32 feePercent;\n uint256 price;\n bool isPaused;\n }\n\n mapping(uint256 =\u003e NFTSet) public sets;\n\n function stake(\n uint256 nftID,\n address payable artist,\n uint32 quantity,\n uint256 price,\n uint256 startTime,\n bytes calldata data\n ) override public nonReentrant {\n require(\n _msgSender() == nftAddress,\n \"Can only stake via NFT_FM contract.\"\n );\n require(\n sets[nftID].artist == address(0),\n \"Sale already exists for that NFT.\"\n );\n uint32 feePercent;\n (feePercent) = abi.decode(data, (uint32));\n sets[nftID] = NFTSet(artist, startTime, quantity, 0, feePercent, price, false);\n }\n\n function buyNFT(uint256 nftID, uint32 quantity) public payable nonReentrant {\n NFTSet memory set = sets[nftID];\n require(set.artist != address(0), \"Sale does not exist.\");\n require(quantity \u003e 0, \"Must select an quantity of tokens\");\n require(block.timestamp \u003e set.startTime, \"Sale has not started yet.\");\n require(!set.isPaused, \"Sale is paused.\");\n require(set.sold + quantity \u003e= quantity, \"Addition overflow\");\n require(set.sold + quantity \u003c= set.quantity, \"Insufficient stock.\");\n\n totalSales++;\n sales[totalSales] = NFTSetSale(\n totalSales,\n block.timestamp,\n _msgSender()\n );\n\n uint256 cost = set.price.mul(quantity);\n uint256 fee = cost.mul(set.feePercent).div(100);\n uint256 artistCut = cost.mul(100 - set.feePercent).div(100);\n require(artistCut + fee == msg.value, \"Exact change required.\");\n sets[nftID].sold = set.sold + quantity;\n sets[nftID].artist.transfer(artistCut);\n authAddress.transfer(fee);\n NFT_TOKEN.safeTransferFrom(\n address(this),\n _msgSender(),\n nftID,\n quantity,\n \"\"\n );\n emit Buy(totalSales, nftID, quantity, _msgSender());\n }\n\n function setAuthAddress(address payable _address) public onlyOwner {\n authAddress = _address;\n }\n\n function setSetPrice(uint256 nftID, uint256 price) public {\n require(sets[nftID].artist == _msgSender(), \"You are not the artist.\");\n sets[nftID].price = price;\n }\n\n function pauseSale(uint256 nftID) public {\n require(sets[nftID].artist == _msgSender(), \"You are not the artist.\");\n sets[nftID].isPaused = true;\n }\n\n function unpauseSale(uint256 nftID) public {\n require(sets[nftID].artist == _msgSender(), \"You are not the artist.\");\n sets[nftID].isPaused = false;\n }\n}\n"},"IERC1155.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"./IERC165.sol\";\n\n/**\n * @dev Required interface of an ERC1155 compliant contract, as defined in the\n * https://eips.ethereum.org/EIPS/eip-1155[EIP].\n *\n * _Available since v3.1._\n */\ninterface IERC1155 is IERC165 {\n /**\n * @dev Emitted when `value` tokens of token type `id` are transferred from `from` to `to` by `operator`.\n */\n event TransferSingle(address indexed operator, address indexed from, address indexed to, uint256 id, uint256 value);\n\n /**\n * @dev Equivalent to multiple {TransferSingle} events, where `operator`, `from` and `to` are the same for all\n * transfers.\n */\n event TransferBatch(address indexed operator, address indexed from, address indexed to, uint256[] ids, uint256[] values);\n\n /**\n * @dev Emitted when `account` grants or revokes permission to `operator` to transfer their tokens, according to\n * `approved`.\n */\n event ApprovalForAll(address indexed account, address indexed operator, bool approved);\n\n /**\n * @dev Emitted when the URI for token type `id` changes to `value`, if it is a non-programmatic URI.\n *\n * If an {URI} event was emitted for `id`, the standard\n * https://eips.ethereum.org/EIPS/eip-1155#metadata-extensions[guarantees] that `value` will equal the value\n * returned by {IERC1155MetadataURI-uri}.\n */\n event URI(string value, uint256 indexed id);\n\n /**\n * @dev Returns the amount of tokens of token type `id` owned by `account`.\n *\n * Requirements:\n *\n * - `account` cannot be the zero address.\n */\n function balanceOf(address account, uint256 id) external view returns (uint256);\n\n /**\n * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {balanceOf}.\n *\n * Requirements:\n *\n * - `accounts` and `ids` must have the same length.\n */\n function balanceOfBatch(address[] calldata accounts, uint256[] calldata ids) external view returns (uint256[] memory);\n\n /**\n * @dev Grants or revokes permission to `operator` to transfer the caller\u0027s tokens, according to `approved`,\n *\n * Emits an {ApprovalForAll} event.\n *\n * Requirements:\n *\n * - `operator` cannot be the caller.\n */\n function setApprovalForAll(address operator, bool approved) external;\n\n /**\n * @dev Returns true if `operator` is approved to transfer ``account``\u0027s tokens.\n *\n * See {setApprovalForAll}.\n */\n function isApprovedForAll(address account, address operator) external view returns (bool);\n\n /**\n * @dev Transfers `amount` tokens of token type `id` from `from` to `to`.\n *\n * Emits a {TransferSingle} event.\n *\n * Requirements:\n *\n * - `to` cannot be the zero address.\n * - If the caller is not `from`, it must be have been approved to spend ``from``\u0027s tokens via {setApprovalForAll}.\n * - `from` must have a balance of tokens of type `id` of at least `amount`.\n * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155Received} and return the\n * acceptance magic value.\n */\n function safeTransferFrom(address from, address to, uint256 id, uint256 amount, bytes calldata data) external;\n\n /**\n * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {safeTransferFrom}.\n *\n * Emits a {TransferBatch} event.\n *\n * Requirements:\n *\n * - `ids` and `amounts` must have the same length.\n * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155BatchReceived} and return the\n * acceptance magic value.\n */\n function safeBatchTransferFrom(address from, address to, uint256[] calldata ids, uint256[] calldata amounts, bytes calldata data) external;\n}\n"},"IERC1155MetadataURI.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"./IERC1155.sol\";\n\n/**\n * @dev Interface of the optional ERC1155MetadataExtension interface, as defined\n * in the https://eips.ethereum.org/EIPS/eip-1155#metadata-extensions[EIP].\n *\n * _Available since v3.1._\n */\ninterface IERC1155MetadataURI is IERC1155 {\n /**\n * @dev Returns the URI for token type `id`.\n *\n * If the `\\{id\\}` substring is present in the URI, it must be replaced by\n * clients with the actual token type ID.\n */\n function uri(uint256 id) external view returns (string memory);\n}\n"},"IERC1155Receiver.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"./IERC165.sol\";\n\n/**\n * _Available since v3.1._\n */\ninterface IERC1155Receiver is IERC165 {\n\n /**\n @dev Handles the receipt of a single ERC1155 token type. This function is\n called at the end of a `safeTransferFrom` after the balance has been updated.\n To accept the transfer, this must return\n `bytes4(keccak256(\"onERC1155Received(address,address,uint256,uint256,bytes)\"))`\n (i.e. 0xf23a6e61, or its own function selector).\n @param operator The address which initiated the transfer (i.e. msg.sender)\n @param from The address which previously owned the token\n @param id The ID of the token being transferred\n @param value The amount of tokens being transferred\n @param data Additional data with no specified format\n @return `bytes4(keccak256(\"onERC1155Received(address,address,uint256,uint256,bytes)\"))` if transfer is allowed\n */\n function onERC1155Received(\n address operator,\n address from,\n uint256 id,\n uint256 value,\n bytes calldata data\n )\n external\n returns(bytes4);\n\n /**\n @dev Handles the receipt of a multiple ERC1155 token types. This function\n is called at the end of a `safeBatchTransferFrom` after the balances have\n been updated. To accept the transfer(s), this must return\n `bytes4(keccak256(\"onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)\"))`\n (i.e. 0xbc197c81, or its own function selector).\n @param operator The address which initiated the batch transfer (i.e. msg.sender)\n @param from The address which previously owned the token\n @param ids An array containing ids of each token being transferred (order and length must match values array)\n @param values An array containing amounts of each token being transferred (order and length must match ids array)\n @param data Additional data with no specified format\n @return `bytes4(keccak256(\"onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)\"))` if transfer is allowed\n */\n function onERC1155BatchReceived(\n address operator,\n address from,\n uint256[] calldata ids,\n uint256[] calldata values,\n bytes calldata data\n )\n external\n returns(bytes4);\n}\n"},"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"},"IERC20.sol":{"content":"// SPDX-License-Identifier: MIT\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 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\u0027s account to `recipient`.\n *\n * Returns a boolean value indicating whether the operation succeeded.\n *\n * Emits a {Transfer} event.\n */\n function transfer(address recipient, 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\u0027s 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\u0027s 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 `sender` to `recipient` using the\n * allowance mechanism. `amount` is then deducted from the caller\u0027s\n * allowance.\n *\n * Returns a boolean value indicating whether the operation succeeded.\n *\n * Emits a {Transfer} event.\n */\n function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);\n\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"},"INFTSale.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity 0.8.4;\n\ninterface INFTSale {\n\tfunction stake(uint256 nftID, address payable artist, uint32 amount, uint256 price, uint256 startTime, bytes calldata data) external;\n}"},"NFTToken.sol":{"content":"// SPDX-License-Identifier: MIT\n\nimport \"./ReentrancyGuard.sol\";\nimport \"./Context.sol\";\nimport \"./Ownable.sol\";\nimport \"./SafeMath.sol\";\nimport \"./Address.sol\";\nimport \"./IERC1155.sol\";\nimport \"./ERC1155.sol\";\nimport \"./FlatPriceSale.sol\";\n\npragma solidity 0.8.4;\n\ncontract NFT_FM is ERC1155, Ownable, ReentrancyGuard {\n constructor(address _authAddress)\n ERC1155(\"https://nftfm.io/api/nft/{id}\")\n {\n authAddress = _authAddress;\n onlyMintersCanMint = false;\n }\n\n address public authAddress;\n uint256 public nftID;\n bool public onlyMintersCanMint;\n mapping(address =\u003e bool) public isMinter;\n mapping(uint256 =\u003e address) public owners;\n mapping(address =\u003e uint256[]) public artists;\n mapping(address =\u003e bool) public isSaleContract;\n\n event MintAndStake(\n uint256 indexed nftID,\n uint32 quantity,\n uint256 price,\n uint256 startTime,\n address saleAddress,\n bytes data,\n string databaseID\n );\n\n function setMinter(address minter, bool status)\n public\n nonReentrant\n onlyOwner\n {\n isMinter[minter] = status;\n }\n\n function setSaleContract(address saleContract, bool status)\n public\n nonReentrant\n onlyOwner\n {\n isSaleContract[saleContract] = status;\n }\n\n function setAuthAddress(address _address) public nonReentrant onlyOwner {\n authAddress = _address;\n }\n\n function mintAndStake(\n uint32 quantity,\n uint256 price,\n uint256 startTime,\n address saleAddress,\n bytes calldata data,\n string calldata databaseID,\n uint8 v,\n bytes32 r,\n bytes32 s\n ) public nonReentrant {\n require(price \u003e= 0, \"Price less than 0\");\n require(quantity \u003e 0, \"Price greater than 1\");\n if (onlyMintersCanMint)\n require(isMinter[_msgSender()] == true, \"Caller is not a minter\");\n require(isSaleContract[saleAddress], \"Unrecognized sale contract.\");\n address signer = ecrecover(\n keccak256(\n abi.encode(\n \"NFTFM_mintAndStake\",\n _msgSender(),\n quantity,\n price,\n startTime,\n saleAddress,\n data\n )\n ),\n v, r, s\n );\n require(signer == authAddress, \"Invalid signature\");\n nftID++;\n owners[nftID] = _msgSender();\n artists[_msgSender()].push(nftID);\n _mint(saleAddress, nftID, quantity, \"initial mint\");\n INFTSale(saleAddress).stake(\n nftID,\n payable(_msgSender()),\n quantity,\n price,\n startTime,\n data\n );\n emit MintAndStake(\n nftID,\n quantity,\n price,\n startTime,\n saleAddress,\n data,\n databaseID\n );\n }\n\n function mint(\n address to,\n uint256 id,\n uint256 quantity\n ) public nonReentrant {\n if (onlyMintersCanMint)\n require(isMinter[_msgSender()] == true, \"Caller is not a minter\");\n require(owners[id] == _msgSender(), \"Caller does not own id\");\n _mint(to, id, quantity, \"the more the merrier!\");\n // TODO should additional minting also be sent to a sales contract?\n }\n\n function burn(uint256 id, uint256 quantity) public nonReentrant {\n _burn(_msgSender(), id, quantity);\n }\n\n function burnBatch(uint256[] memory ids, uint256[] memory quantitys)\n public\n nonReentrant\n {\n _burnBatch(_msgSender(), ids, quantitys);\n }\n\n function getArtistsNFTs(address _owner)\n public\n view\n returns (uint256[] memory)\n {\n return artists[_owner];\n }\n\n function getFullBalance(address user)\n public\n view\n returns (uint256[] memory, uint256[] memory)\n {\n uint256[] memory ids = new uint256[](nftID);\n uint256[] memory balances = new uint256[](nftID);\n for (uint256 id = 1; id \u003c= nftID; id++) {\n ids[id - 1] = id;\n balances[id - 1] = balanceOf(user, id);\n }\n return (ids, balances);\n }\n}\n"},"Ownable.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"./Context.sol\";\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 address msgSender = _msgSender();\n _owner = msgSender;\n emit OwnershipTransferred(address(0), 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 emit OwnershipTransferred(_owner, address(0));\n _owner = 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 emit OwnershipTransferred(_owner, newOwner);\n _owner = newOwner;\n }\n}\n"},"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\u0027s contents, replace the bits taken up by the boolean, and then write\n // back. This is the compiler\u0027s 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\u0027s 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"},"SafeMath.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\n// CAUTION\n// This version of SafeMath should only be used with Solidity 0.8 or later,\n// because it relies on the compiler\u0027s built in overflow checks.\n\n/**\n * @dev Wrappers over Solidity\u0027s arithmetic operations.\n *\n * NOTE: `SafeMath` is no longer needed starting with Solidity 0.8. The compiler\n * now has built in overflow checking.\n */\nlibrary SafeMath {\n /**\n * @dev Returns the addition of two unsigned integers, with an overflow flag.\n *\n * _Available since v3.4._\n */\n function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n unchecked {\n uint256 c = a + b;\n if (c \u003c a) return (false, 0);\n return (true, c);\n }\n }\n\n /**\n * @dev Returns the substraction of two unsigned integers, with an overflow flag.\n *\n * _Available since v3.4._\n */\n function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n unchecked {\n if (b \u003e a) return (false, 0);\n return (true, a - b);\n }\n }\n\n /**\n * @dev Returns the multiplication of two unsigned integers, with an overflow flag.\n *\n * _Available since v3.4._\n */\n function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n unchecked {\n // Gas optimization: this is cheaper than requiring \u0027a\u0027 not being zero, but the\n // benefit is lost if \u0027b\u0027 is also tested.\n // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522\n if (a == 0) return (true, 0);\n uint256 c = a * b;\n if (c / a != b) return (false, 0);\n return (true, c);\n }\n }\n\n /**\n * @dev Returns the division of two unsigned integers, with a division by zero flag.\n *\n * _Available since v3.4._\n */\n function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n unchecked {\n if (b == 0) return (false, 0);\n return (true, a / b);\n }\n }\n\n /**\n * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.\n *\n * _Available since v3.4._\n */\n function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n unchecked {\n if (b == 0) return (false, 0);\n return (true, a % b);\n }\n }\n\n /**\n * @dev Returns the addition of two unsigned integers, reverting on\n * overflow.\n *\n * Counterpart to Solidity\u0027s `+` operator.\n *\n * Requirements:\n *\n * - Addition cannot overflow.\n */\n function add(uint256 a, uint256 b) internal pure returns (uint256) {\n return a + b;\n }\n\n /**\n * @dev Returns the subtraction of two unsigned integers, reverting on\n * overflow (when the result is negative).\n *\n * Counterpart to Solidity\u0027s `-` operator.\n *\n * Requirements:\n *\n * - Subtraction cannot overflow.\n */\n function sub(uint256 a, uint256 b) internal pure returns (uint256) {\n return a - b;\n }\n\n /**\n * @dev Returns the multiplication of two unsigned integers, reverting on\n * overflow.\n *\n * Counterpart to Solidity\u0027s `*` operator.\n *\n * Requirements:\n *\n * - Multiplication cannot overflow.\n */\n function mul(uint256 a, uint256 b) internal pure returns (uint256) {\n return a * b;\n }\n\n /**\n * @dev Returns the integer division of two unsigned integers, reverting on\n * division by zero. The result is rounded towards zero.\n *\n * Counterpart to Solidity\u0027s `/` operator.\n *\n * Requirements:\n *\n * - The divisor cannot be zero.\n */\n function div(uint256 a, uint256 b) internal pure returns (uint256) {\n return a / b;\n }\n\n /**\n * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\n * reverting when dividing by zero.\n *\n * Counterpart to Solidity\u0027s `%` operator. This function uses a `revert`\n * opcode (which leaves remaining gas untouched) while Solidity uses an\n * invalid opcode to revert (consuming all remaining gas).\n *\n * Requirements:\n *\n * - The divisor cannot be zero.\n */\n function mod(uint256 a, uint256 b) internal pure returns (uint256) {\n return a % b;\n }\n\n /**\n * @dev Returns the subtraction of two unsigned integers, reverting with custom message on\n * overflow (when the result is negative).\n *\n * CAUTION: This function is deprecated because it requires allocating memory for the error\n * message unnecessarily. For custom revert reasons use {trySub}.\n *\n * Counterpart to Solidity\u0027s `-` operator.\n *\n * Requirements:\n *\n * - Subtraction cannot overflow.\n */\n function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n unchecked {\n require(b \u003c= a, errorMessage);\n return a - b;\n }\n }\n\n /**\n * @dev Returns the integer division of two unsigned integers, reverting with custom message on\n * division by zero. The result is rounded towards zero.\n *\n * Counterpart to Solidity\u0027s `%` operator. This function uses a `revert`\n * opcode (which leaves remaining gas untouched) while Solidity uses an\n * invalid opcode to revert (consuming all remaining gas).\n *\n * Counterpart to Solidity\u0027s `/` operator. Note: this function uses a\n * `revert` opcode (which leaves remaining gas untouched) while Solidity\n * uses an invalid opcode to revert (consuming all remaining gas).\n *\n * Requirements:\n *\n * - The divisor cannot be zero.\n */\n function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n unchecked {\n require(b \u003e 0, errorMessage);\n return a / b;\n }\n }\n\n /**\n * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\n * reverting with custom message when dividing by zero.\n *\n * CAUTION: This function is deprecated because it requires allocating memory for the error\n * message unnecessarily. For custom revert reasons use {tryMod}.\n *\n * Counterpart to Solidity\u0027s `%` operator. This function uses a `revert`\n * opcode (which leaves remaining gas untouched) while Solidity uses an\n * invalid opcode to revert (consuming all remaining gas).\n *\n * Requirements:\n *\n * - The divisor cannot be zero.\n */\n function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n unchecked {\n require(b \u003e 0, errorMessage);\n return a % b;\n }\n }\n}\n"}}
File 2 of 2: NFT_FM
{"Address.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Collection of functions related to the address type\n */\nlibrary Address {\n /**\n * @dev Returns true if `account` is a contract.\n *\n * [IMPORTANT]\n * ====\n * It is unsafe to assume that an address for which this function returns\n * false is an externally-owned account (EOA) and not a contract.\n *\n * Among others, `isContract` will return false for the following\n * types of addresses:\n *\n * - an externally-owned account\n * - a contract in construction\n * - an address where a contract will be created\n * - an address where a contract lived, but was destroyed\n * ====\n */\n function isContract(address account) internal view returns (bool) {\n // This method relies on extcodesize, which returns 0 for contracts in\n // construction, since the code is only stored at the end of the\n // constructor execution.\n\n uint256 size;\n // solhint-disable-next-line no-inline-assembly\n assembly { size := extcodesize(account) }\n return size \u003e 0;\n }\n\n /**\n * @dev Replacement for Solidity\u0027s `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 \u003e= amount, \"Address: insufficient balance\");\n\n // solhint-disable-next-line avoid-low-level-calls, avoid-call-value\n (bool success, ) = recipient.call{ value: amount }(\"\");\n require(success, \"Address: unable to send value, recipient may have reverted\");\n }\n\n /**\n * @dev Performs a Solidity function call using a low level `call`. A\n * plain`call` is an unsafe replacement for a function call: use this\n * function instead.\n *\n * If `target` reverts with a revert reason, it is bubbled up by this\n * function (like regular Solidity function calls).\n *\n * Returns the raw returned data. To convert to the expected return value,\n * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].\n *\n * Requirements:\n *\n * - `target` must be a contract.\n * - calling `target` with `data` must not revert.\n *\n * _Available since v3.1._\n */\n function functionCall(address target, bytes memory data) internal returns (bytes memory) {\n return functionCall(target, data, \"Address: low-level call failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with\n * `errorMessage` as a fallback revert reason when `target` reverts.\n *\n * _Available since v3.1._\n */\n function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {\n return functionCallWithValue(target, data, 0, errorMessage);\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n * but also transferring `value` wei to `target`.\n *\n * Requirements:\n *\n * - the calling contract must have an ETH balance of at least `value`.\n * - the called Solidity function must be `payable`.\n *\n * _Available since v3.1._\n */\n function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {\n return functionCallWithValue(target, data, value, \"Address: low-level call with value failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but\n * with `errorMessage` as a fallback revert reason when `target` reverts.\n *\n * _Available since v3.1._\n */\n function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {\n require(address(this).balance \u003e= value, \"Address: insufficient balance for call\");\n require(isContract(target), \"Address: call to non-contract\");\n\n // solhint-disable-next-line avoid-low-level-calls\n (bool success, bytes memory returndata) = target.call{ value: value }(data);\n return _verifyCallResult(success, returndata, errorMessage);\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n * but performing a static call.\n *\n * _Available since v3.3._\n */\n function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {\n return functionStaticCall(target, data, \"Address: low-level static call failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n * but performing a static call.\n *\n * _Available since v3.3._\n */\n function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {\n require(isContract(target), \"Address: static call to non-contract\");\n\n // solhint-disable-next-line avoid-low-level-calls\n (bool success, bytes memory returndata) = target.staticcall(data);\n return _verifyCallResult(success, returndata, errorMessage);\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n * but performing a delegate call.\n *\n * _Available since v3.4._\n */\n function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {\n return functionDelegateCall(target, data, \"Address: low-level delegate call failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n * but performing a delegate call.\n *\n * _Available since v3.4._\n */\n function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {\n require(isContract(target), \"Address: delegate call to non-contract\");\n\n // solhint-disable-next-line avoid-low-level-calls\n (bool success, bytes memory returndata) = target.delegatecall(data);\n return _verifyCallResult(success, returndata, errorMessage);\n }\n\n function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {\n if (success) {\n return returndata;\n } else {\n // Look for revert reason and bubble it up if present\n if (returndata.length \u003e 0) {\n // The easiest way to bubble the revert reason is using memory via assembly\n\n // solhint-disable-next-line no-inline-assembly\n assembly {\n let returndata_size := mload(returndata)\n revert(add(32, returndata), returndata_size)\n }\n } else {\n revert(errorMessage);\n }\n }\n }\n}\n"},"Context.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\n/*\n * @dev Provides information about the current execution context, including the\n * sender of the transaction and its data. While these are generally available\n * via msg.sender and msg.data, they should not be accessed in such a direct\n * manner, since when dealing with meta-transactions the account sending and\n * paying for execution may not be the actual sender (as far as an application\n * is concerned).\n *\n * This contract is only required for intermediate, library-like contracts.\n */\nabstract contract Context {\n function _msgSender() internal view virtual returns (address) {\n return msg.sender;\n }\n\n function _msgData() internal view virtual returns (bytes calldata) {\n this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691\n return msg.data;\n }\n}\n"},"ERC1155.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"./IERC1155.sol\";\nimport \"./IERC1155Receiver.sol\";\nimport \"./IERC1155MetadataURI.sol\";\nimport \"./Address.sol\";\nimport \"./Context.sol\";\nimport \"./ERC165.sol\";\n\n/**\n *\n * @dev Implementation of the basic standard multi-token.\n * See https://eips.ethereum.org/EIPS/eip-1155\n * Originally based on code by Enjin: https://github.com/enjin/erc-1155\n *\n * _Available since v3.1._\n */\ncontract ERC1155 is Context, ERC165, IERC1155, IERC1155MetadataURI {\n using Address for address;\n\n // Mapping from token ID to account balances\n mapping (uint256 =\u003e mapping(address =\u003e uint256)) private _balances;\n\n // Mapping from account to operator approvals\n mapping (address =\u003e mapping(address =\u003e bool)) private _operatorApprovals;\n\n // Used as the URI for all token types by relying on ID substitution, e.g. https://token-cdn-domain/{id}.json\n string private _uri;\n\n /**\n * @dev See {_setURI}.\n */\n constructor (string memory uri_) {\n _setURI(uri_);\n }\n\n /**\n * @dev See {IERC165-supportsInterface}.\n */\n function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {\n return interfaceId == type(IERC1155).interfaceId\n || interfaceId == type(IERC1155MetadataURI).interfaceId\n || super.supportsInterface(interfaceId);\n }\n\n /**\n * @dev See {IERC1155MetadataURI-uri}.\n *\n * This implementation returns the same URI for *all* token types. It relies\n * on the token type ID substitution mechanism\n * https://eips.ethereum.org/EIPS/eip-1155#metadata[defined in the EIP].\n *\n * Clients calling this function must replace the `\\{id\\}` substring with the\n * actual token type ID.\n */\n function uri(uint256) public view virtual override returns (string memory) {\n return _uri;\n }\n\n /**\n * @dev See {IERC1155-balanceOf}.\n *\n * Requirements:\n *\n * - `account` cannot be the zero address.\n */\n function balanceOf(address account, uint256 id) public view virtual override returns (uint256) {\n require(account != address(0), \"ERC1155: balance query for the zero address\");\n return _balances[id][account];\n }\n\n /**\n * @dev See {IERC1155-balanceOfBatch}.\n *\n * Requirements:\n *\n * - `accounts` and `ids` must have the same length.\n */\n function balanceOfBatch(\n address[] memory accounts,\n uint256[] memory ids\n )\n public\n view\n virtual\n override\n returns (uint256[] memory)\n {\n require(accounts.length == ids.length, \"ERC1155: accounts and ids length mismatch\");\n\n uint256[] memory batchBalances = new uint256[](accounts.length);\n\n for (uint256 i = 0; i \u003c accounts.length; ++i) {\n batchBalances[i] = balanceOf(accounts[i], ids[i]);\n }\n\n return batchBalances;\n }\n\n /**\n * @dev See {IERC1155-setApprovalForAll}.\n */\n function setApprovalForAll(address operator, bool approved) public virtual override {\n require(_msgSender() != operator, \"ERC1155: setting approval status for self\");\n\n _operatorApprovals[_msgSender()][operator] = approved;\n emit ApprovalForAll(_msgSender(), operator, approved);\n }\n\n /**\n * @dev See {IERC1155-isApprovedForAll}.\n */\n function isApprovedForAll(address account, address operator) public view virtual override returns (bool) {\n return _operatorApprovals[account][operator];\n }\n\n /**\n * @dev See {IERC1155-safeTransferFrom}.\n */\n function safeTransferFrom(\n address from,\n address to,\n uint256 id,\n uint256 amount,\n bytes memory data\n )\n public\n virtual\n override\n {\n require(\n from == _msgSender() || isApprovedForAll(from, _msgSender()),\n \"ERC1155: caller is not owner nor approved\"\n );\n _safeTransferFrom(from, to, id, amount, data);\n }\n\n /**\n * @dev See {IERC1155-safeBatchTransferFrom}.\n */\n function safeBatchTransferFrom(\n address from,\n address to,\n uint256[] memory ids,\n uint256[] memory amounts,\n bytes memory data\n )\n public\n virtual\n override\n {\n require(\n from == _msgSender() || isApprovedForAll(from, _msgSender()),\n \"ERC1155: transfer caller is not owner nor approved\"\n );\n _safeBatchTransferFrom(from, to, ids, amounts, data);\n }\n\n /**\n * @dev Transfers `amount` tokens of token type `id` from `from` to `to`.\n *\n * Emits a {TransferSingle} event.\n *\n * Requirements:\n *\n * - `to` cannot be the zero address.\n * - `from` must have a balance of tokens of type `id` of at least `amount`.\n * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155Received} and return the\n * acceptance magic value.\n */\n function _safeTransferFrom(\n address from,\n address to,\n uint256 id,\n uint256 amount,\n bytes memory data\n )\n internal\n virtual\n {\n require(to != address(0), \"ERC1155: transfer to the zero address\");\n\n address operator = _msgSender();\n\n _beforeTokenTransfer(operator, from, to, _asSingletonArray(id), _asSingletonArray(amount), data);\n\n uint256 fromBalance = _balances[id][from];\n require(fromBalance \u003e= amount, \"ERC1155: insufficient balance for transfer\");\n _balances[id][from] = fromBalance - amount;\n _balances[id][to] += amount;\n\n emit TransferSingle(operator, from, to, id, amount);\n\n _doSafeTransferAcceptanceCheck(operator, from, to, id, amount, data);\n }\n\n /**\n * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {_safeTransferFrom}.\n *\n * Emits a {TransferBatch} event.\n *\n * Requirements:\n *\n * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155BatchReceived} and return the\n * acceptance magic value.\n */\n function _safeBatchTransferFrom(\n address from,\n address to,\n uint256[] memory ids,\n uint256[] memory amounts,\n bytes memory data\n )\n internal\n virtual\n {\n require(ids.length == amounts.length, \"ERC1155: ids and amounts length mismatch\");\n require(to != address(0), \"ERC1155: transfer to the zero address\");\n\n address operator = _msgSender();\n\n _beforeTokenTransfer(operator, from, to, ids, amounts, data);\n\n for (uint256 i = 0; i \u003c ids.length; ++i) {\n uint256 id = ids[i];\n uint256 amount = amounts[i];\n\n uint256 fromBalance = _balances[id][from];\n require(fromBalance \u003e= amount, \"ERC1155: insufficient balance for transfer\");\n _balances[id][from] = fromBalance - amount;\n _balances[id][to] += amount;\n }\n\n emit TransferBatch(operator, from, to, ids, amounts);\n\n _doSafeBatchTransferAcceptanceCheck(operator, from, to, ids, amounts, data);\n }\n\n /**\n * @dev Sets a new URI for all token types, by relying on the token type ID\n * substitution mechanism\n * https://eips.ethereum.org/EIPS/eip-1155#metadata[defined in the EIP].\n *\n * By this mechanism, any occurrence of the `\\{id\\}` substring in either the\n * URI or any of the amounts in the JSON file at said URI will be replaced by\n * clients with the token type ID.\n *\n * For example, the `https://token-cdn-domain/\\{id\\}.json` URI would be\n * interpreted by clients as\n * `https://token-cdn-domain/000000000000000000000000000000000000000000000000000000000004cce0.json`\n * for token type ID 0x4cce0.\n *\n * See {uri}.\n *\n * Because these URIs cannot be meaningfully represented by the {URI} event,\n * this function emits no events.\n */\n function _setURI(string memory newuri) internal virtual {\n _uri = newuri;\n }\n\n /**\n * @dev Creates `amount` tokens of token type `id`, and assigns them to `account`.\n *\n * Emits a {TransferSingle} event.\n *\n * Requirements:\n *\n * - `account` cannot be the zero address.\n * - If `account` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155Received} and return the\n * acceptance magic value.\n */\n function _mint(address account, uint256 id, uint256 amount, bytes memory data) internal virtual {\n require(account != address(0), \"ERC1155: mint to the zero address\");\n\n address operator = _msgSender();\n\n _beforeTokenTransfer(operator, address(0), account, _asSingletonArray(id), _asSingletonArray(amount), data);\n\n _balances[id][account] += amount;\n emit TransferSingle(operator, address(0), account, id, amount);\n\n _doSafeTransferAcceptanceCheck(operator, address(0), account, id, amount, data);\n }\n\n /**\n * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {_mint}.\n *\n * Requirements:\n *\n * - `ids` and `amounts` must have the same length.\n * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155BatchReceived} and return the\n * acceptance magic value.\n */\n function _mintBatch(address to, uint256[] memory ids, uint256[] memory amounts, bytes memory data) internal virtual {\n require(to != address(0), \"ERC1155: mint to the zero address\");\n require(ids.length == amounts.length, \"ERC1155: ids and amounts length mismatch\");\n\n address operator = _msgSender();\n\n _beforeTokenTransfer(operator, address(0), to, ids, amounts, data);\n\n for (uint i = 0; i \u003c ids.length; i++) {\n _balances[ids[i]][to] += amounts[i];\n }\n\n emit TransferBatch(operator, address(0), to, ids, amounts);\n\n _doSafeBatchTransferAcceptanceCheck(operator, address(0), to, ids, amounts, data);\n }\n\n /**\n * @dev Destroys `amount` tokens of token type `id` from `account`\n *\n * Requirements:\n *\n * - `account` cannot be the zero address.\n * - `account` must have at least `amount` tokens of token type `id`.\n */\n function _burn(address account, uint256 id, uint256 amount) internal virtual {\n require(account != address(0), \"ERC1155: burn from the zero address\");\n\n address operator = _msgSender();\n\n _beforeTokenTransfer(operator, account, address(0), _asSingletonArray(id), _asSingletonArray(amount), \"\");\n\n uint256 accountBalance = _balances[id][account];\n require(accountBalance \u003e= amount, \"ERC1155: burn amount exceeds balance\");\n _balances[id][account] = accountBalance - amount;\n\n emit TransferSingle(operator, account, address(0), id, amount);\n }\n\n /**\n * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {_burn}.\n *\n * Requirements:\n *\n * - `ids` and `amounts` must have the same length.\n */\n function _burnBatch(address account, uint256[] memory ids, uint256[] memory amounts) internal virtual {\n require(account != address(0), \"ERC1155: burn from the zero address\");\n require(ids.length == amounts.length, \"ERC1155: ids and amounts length mismatch\");\n\n address operator = _msgSender();\n\n _beforeTokenTransfer(operator, account, address(0), ids, amounts, \"\");\n\n for (uint i = 0; i \u003c ids.length; i++) {\n uint256 id = ids[i];\n uint256 amount = amounts[i];\n\n uint256 accountBalance = _balances[id][account];\n require(accountBalance \u003e= amount, \"ERC1155: burn amount exceeds balance\");\n _balances[id][account] = accountBalance - amount;\n }\n\n emit TransferBatch(operator, account, address(0), ids, amounts);\n }\n\n /**\n * @dev Hook that is called before any token transfer. This includes minting\n * and burning, as well as batched variants.\n *\n * The same hook is called on both single and batched variants. For single\n * transfers, the length of the `id` and `amount` arrays will be 1.\n *\n * Calling conditions (for each `id` and `amount` pair):\n *\n * - When `from` and `to` are both non-zero, `amount` of ``from``\u0027s tokens\n * of token type `id` will be transferred to `to`.\n * - When `from` is zero, `amount` tokens of token type `id` will be minted\n * for `to`.\n * - when `to` is zero, `amount` of ``from``\u0027s tokens of token type `id`\n * will be burned.\n * - `from` and `to` are never both zero.\n * - `ids` and `amounts` have the same, non-zero length.\n *\n * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].\n */\n function _beforeTokenTransfer(\n address operator,\n address from,\n address to,\n uint256[] memory ids,\n uint256[] memory amounts,\n bytes memory data\n )\n internal\n virtual\n { }\n\n function _doSafeTransferAcceptanceCheck(\n address operator,\n address from,\n address to,\n uint256 id,\n uint256 amount,\n bytes memory data\n )\n private\n {\n if (to.isContract()) {\n try IERC1155Receiver(to).onERC1155Received(operator, from, id, amount, data) returns (bytes4 response) {\n if (response != IERC1155Receiver(to).onERC1155Received.selector) {\n revert(\"ERC1155: ERC1155Receiver rejected tokens\");\n }\n } catch Error(string memory reason) {\n revert(reason);\n } catch {\n revert(\"ERC1155: transfer to non ERC1155Receiver implementer\");\n }\n }\n }\n\n function _doSafeBatchTransferAcceptanceCheck(\n address operator,\n address from,\n address to,\n uint256[] memory ids,\n uint256[] memory amounts,\n bytes memory data\n )\n private\n {\n if (to.isContract()) {\n try IERC1155Receiver(to).onERC1155BatchReceived(operator, from, ids, amounts, data) returns (bytes4 response) {\n if (response != IERC1155Receiver(to).onERC1155BatchReceived.selector) {\n revert(\"ERC1155: ERC1155Receiver rejected tokens\");\n }\n } catch Error(string memory reason) {\n revert(reason);\n } catch {\n revert(\"ERC1155: transfer to non ERC1155Receiver implementer\");\n }\n }\n }\n\n function _asSingletonArray(uint256 element) private pure returns (uint256[] memory) {\n uint256[] memory array = new uint256[](1);\n array[0] = element;\n\n return array;\n }\n}\n"},"ERC1155Holder.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"./ERC1155Receiver.sol\";\n\n/**\n * @dev _Available since v3.1._\n */\ncontract ERC1155Holder is ERC1155Receiver {\n function onERC1155Received(address, address, uint256, uint256, bytes memory) public virtual override returns (bytes4) {\n return this.onERC1155Received.selector;\n }\n\n function onERC1155BatchReceived(address, address, uint256[] memory, uint256[] memory, bytes memory) public virtual override returns (bytes4) {\n return this.onERC1155BatchReceived.selector;\n }\n}\n"},"ERC1155Receiver.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"./IERC1155Receiver.sol\";\nimport \"./ERC165.sol\";\n\n/**\n * @dev _Available since v3.1._\n */\nabstract contract ERC1155Receiver is ERC165, IERC1155Receiver {\n /**\n * @dev See {IERC165-supportsInterface}.\n */\n function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {\n return interfaceId == type(IERC1155Receiver).interfaceId\n || super.supportsInterface(interfaceId);\n }\n}\n"},"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}"},"FlatPriceSale.sol":{"content":"// SPDX-License-Identifier: MIT\n\nimport \"./Context.sol\";\nimport \"./SafeMath.sol\";\nimport \"./Ownable.sol\";\nimport \"./IERC20.sol\";\nimport \"./IERC1155.sol\";\nimport \"./ReentrancyGuard.sol\";\nimport \"./ERC1155Holder.sol\";\nimport \"./INFTSale.sol\";\n\npragma solidity 0.8.4;\n\ncontract FlatPriceSale is Context, Ownable, ReentrancyGuard, ERC1155Holder, INFTSale {\n using SafeMath for uint256;\n\n constructor(address nftToken, address payable _authAddress) {\n NFT_TOKEN = IERC1155(nftToken);\n nftAddress = nftToken;\n authAddress = _authAddress;\n }\n\n event Buy(\n uint256 indexed saleId,\n uint256 nftID,\n uint256 quantity,\n address indexed account\n );\n\n address payable public authAddress;\n address public nftAddress;\n IERC1155 private NFT_TOKEN;\n\n struct NFTSetSale {\n uint32 saleId;\n uint256 timestamp;\n address buyer;\n }\n\n mapping(uint32 =\u003e NFTSetSale) public sales;\n uint32 public totalSales;\n\n struct NFTSet {\n address payable artist;\n uint256 startTime;\n uint32 quantity;\n uint32 sold;\n uint32 feePercent;\n uint256 price;\n bool isPaused;\n }\n\n mapping(uint256 =\u003e NFTSet) public sets;\n\n function stake(\n uint256 nftID,\n address payable artist,\n uint32 quantity,\n uint256 price,\n uint256 startTime,\n bytes calldata data\n ) override public nonReentrant {\n require(\n _msgSender() == nftAddress,\n \"Can only stake via NFT_FM contract.\"\n );\n require(\n sets[nftID].artist == address(0),\n \"Sale already exists for that NFT.\"\n );\n uint32 feePercent;\n (feePercent) = abi.decode(data, (uint32));\n sets[nftID] = NFTSet(artist, startTime, quantity, 0, feePercent, price, false);\n }\n\n function buyNFT(uint256 nftID, uint32 quantity) public payable nonReentrant {\n NFTSet memory set = sets[nftID];\n require(set.artist != address(0), \"Sale does not exist.\");\n require(quantity \u003e 0, \"Must select an quantity of tokens\");\n require(block.timestamp \u003e set.startTime, \"Sale has not started yet.\");\n require(!set.isPaused, \"Sale is paused.\");\n require(set.sold + quantity \u003e= quantity, \"Addition overflow\");\n require(set.sold + quantity \u003c= set.quantity, \"Insufficient stock.\");\n\n totalSales++;\n sales[totalSales] = NFTSetSale(\n totalSales,\n block.timestamp,\n _msgSender()\n );\n\n uint256 cost = set.price.mul(quantity);\n uint256 fee = cost.mul(set.feePercent).div(100);\n uint256 artistCut = cost.mul(100 - set.feePercent).div(100);\n require(artistCut + fee == msg.value, \"Exact change required.\");\n sets[nftID].sold = set.sold + quantity;\n sets[nftID].artist.transfer(artistCut);\n authAddress.transfer(fee);\n NFT_TOKEN.safeTransferFrom(\n address(this),\n _msgSender(),\n nftID,\n quantity,\n \"\"\n );\n emit Buy(totalSales, nftID, quantity, _msgSender());\n }\n\n function setAuthAddress(address payable _address) public onlyOwner {\n authAddress = _address;\n }\n\n function setSetPrice(uint256 nftID, uint256 price) public {\n require(sets[nftID].artist == _msgSender(), \"You are not the artist.\");\n sets[nftID].price = price;\n }\n\n function pauseSale(uint256 nftID) public {\n require(sets[nftID].artist == _msgSender(), \"You are not the artist.\");\n sets[nftID].isPaused = true;\n }\n\n function unpauseSale(uint256 nftID) public {\n require(sets[nftID].artist == _msgSender(), \"You are not the artist.\");\n sets[nftID].isPaused = false;\n }\n}\n"},"IERC1155.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"./IERC165.sol\";\n\n/**\n * @dev Required interface of an ERC1155 compliant contract, as defined in the\n * https://eips.ethereum.org/EIPS/eip-1155[EIP].\n *\n * _Available since v3.1._\n */\ninterface IERC1155 is IERC165 {\n /**\n * @dev Emitted when `value` tokens of token type `id` are transferred from `from` to `to` by `operator`.\n */\n event TransferSingle(address indexed operator, address indexed from, address indexed to, uint256 id, uint256 value);\n\n /**\n * @dev Equivalent to multiple {TransferSingle} events, where `operator`, `from` and `to` are the same for all\n * transfers.\n */\n event TransferBatch(address indexed operator, address indexed from, address indexed to, uint256[] ids, uint256[] values);\n\n /**\n * @dev Emitted when `account` grants or revokes permission to `operator` to transfer their tokens, according to\n * `approved`.\n */\n event ApprovalForAll(address indexed account, address indexed operator, bool approved);\n\n /**\n * @dev Emitted when the URI for token type `id` changes to `value`, if it is a non-programmatic URI.\n *\n * If an {URI} event was emitted for `id`, the standard\n * https://eips.ethereum.org/EIPS/eip-1155#metadata-extensions[guarantees] that `value` will equal the value\n * returned by {IERC1155MetadataURI-uri}.\n */\n event URI(string value, uint256 indexed id);\n\n /**\n * @dev Returns the amount of tokens of token type `id` owned by `account`.\n *\n * Requirements:\n *\n * - `account` cannot be the zero address.\n */\n function balanceOf(address account, uint256 id) external view returns (uint256);\n\n /**\n * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {balanceOf}.\n *\n * Requirements:\n *\n * - `accounts` and `ids` must have the same length.\n */\n function balanceOfBatch(address[] calldata accounts, uint256[] calldata ids) external view returns (uint256[] memory);\n\n /**\n * @dev Grants or revokes permission to `operator` to transfer the caller\u0027s tokens, according to `approved`,\n *\n * Emits an {ApprovalForAll} event.\n *\n * Requirements:\n *\n * - `operator` cannot be the caller.\n */\n function setApprovalForAll(address operator, bool approved) external;\n\n /**\n * @dev Returns true if `operator` is approved to transfer ``account``\u0027s tokens.\n *\n * See {setApprovalForAll}.\n */\n function isApprovedForAll(address account, address operator) external view returns (bool);\n\n /**\n * @dev Transfers `amount` tokens of token type `id` from `from` to `to`.\n *\n * Emits a {TransferSingle} event.\n *\n * Requirements:\n *\n * - `to` cannot be the zero address.\n * - If the caller is not `from`, it must be have been approved to spend ``from``\u0027s tokens via {setApprovalForAll}.\n * - `from` must have a balance of tokens of type `id` of at least `amount`.\n * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155Received} and return the\n * acceptance magic value.\n */\n function safeTransferFrom(address from, address to, uint256 id, uint256 amount, bytes calldata data) external;\n\n /**\n * @dev xref:ROOT:erc1155.adoc#batch-operations[Batched] version of {safeTransferFrom}.\n *\n * Emits a {TransferBatch} event.\n *\n * Requirements:\n *\n * - `ids` and `amounts` must have the same length.\n * - If `to` refers to a smart contract, it must implement {IERC1155Receiver-onERC1155BatchReceived} and return the\n * acceptance magic value.\n */\n function safeBatchTransferFrom(address from, address to, uint256[] calldata ids, uint256[] calldata amounts, bytes calldata data) external;\n}\n"},"IERC1155MetadataURI.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"./IERC1155.sol\";\n\n/**\n * @dev Interface of the optional ERC1155MetadataExtension interface, as defined\n * in the https://eips.ethereum.org/EIPS/eip-1155#metadata-extensions[EIP].\n *\n * _Available since v3.1._\n */\ninterface IERC1155MetadataURI is IERC1155 {\n /**\n * @dev Returns the URI for token type `id`.\n *\n * If the `\\{id\\}` substring is present in the URI, it must be replaced by\n * clients with the actual token type ID.\n */\n function uri(uint256 id) external view returns (string memory);\n}\n"},"IERC1155Receiver.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"./IERC165.sol\";\n\n/**\n * _Available since v3.1._\n */\ninterface IERC1155Receiver is IERC165 {\n\n /**\n @dev Handles the receipt of a single ERC1155 token type. This function is\n called at the end of a `safeTransferFrom` after the balance has been updated.\n To accept the transfer, this must return\n `bytes4(keccak256(\"onERC1155Received(address,address,uint256,uint256,bytes)\"))`\n (i.e. 0xf23a6e61, or its own function selector).\n @param operator The address which initiated the transfer (i.e. msg.sender)\n @param from The address which previously owned the token\n @param id The ID of the token being transferred\n @param value The amount of tokens being transferred\n @param data Additional data with no specified format\n @return `bytes4(keccak256(\"onERC1155Received(address,address,uint256,uint256,bytes)\"))` if transfer is allowed\n */\n function onERC1155Received(\n address operator,\n address from,\n uint256 id,\n uint256 value,\n bytes calldata data\n )\n external\n returns(bytes4);\n\n /**\n @dev Handles the receipt of a multiple ERC1155 token types. This function\n is called at the end of a `safeBatchTransferFrom` after the balances have\n been updated. To accept the transfer(s), this must return\n `bytes4(keccak256(\"onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)\"))`\n (i.e. 0xbc197c81, or its own function selector).\n @param operator The address which initiated the batch transfer (i.e. msg.sender)\n @param from The address which previously owned the token\n @param ids An array containing ids of each token being transferred (order and length must match values array)\n @param values An array containing amounts of each token being transferred (order and length must match ids array)\n @param data Additional data with no specified format\n @return `bytes4(keccak256(\"onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)\"))` if transfer is allowed\n */\n function onERC1155BatchReceived(\n address operator,\n address from,\n uint256[] calldata ids,\n uint256[] calldata values,\n bytes calldata data\n )\n external\n returns(bytes4);\n}\n"},"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"},"IERC20.sol":{"content":"// SPDX-License-Identifier: MIT\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 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\u0027s account to `recipient`.\n *\n * Returns a boolean value indicating whether the operation succeeded.\n *\n * Emits a {Transfer} event.\n */\n function transfer(address recipient, 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\u0027s 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\u0027s 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 `sender` to `recipient` using the\n * allowance mechanism. `amount` is then deducted from the caller\u0027s\n * allowance.\n *\n * Returns a boolean value indicating whether the operation succeeded.\n *\n * Emits a {Transfer} event.\n */\n function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);\n\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"},"INFTSale.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity 0.8.4;\n\ninterface INFTSale {\n\tfunction stake(uint256 nftID, address payable artist, uint32 amount, uint256 price, uint256 startTime, bytes calldata data) external;\n}"},"NFTToken.sol":{"content":"// SPDX-License-Identifier: MIT\n\nimport \"./ReentrancyGuard.sol\";\nimport \"./Context.sol\";\nimport \"./Ownable.sol\";\nimport \"./SafeMath.sol\";\nimport \"./Address.sol\";\nimport \"./IERC1155.sol\";\nimport \"./ERC1155.sol\";\nimport \"./FlatPriceSale.sol\";\n\npragma solidity 0.8.4;\n\ncontract NFT_FM is ERC1155, Ownable, ReentrancyGuard {\n constructor(address _authAddress)\n ERC1155(\"https://nftfm.io/api/nft/{id}\")\n {\n authAddress = _authAddress;\n onlyMintersCanMint = false;\n }\n\n address public authAddress;\n uint256 public nftID;\n bool public onlyMintersCanMint;\n mapping(address =\u003e bool) public isMinter;\n mapping(uint256 =\u003e address) public owners;\n mapping(address =\u003e uint256[]) public artists;\n mapping(address =\u003e bool) public isSaleContract;\n\n event MintAndStake(\n uint256 indexed nftID,\n uint32 quantity,\n uint256 price,\n uint256 startTime,\n address saleAddress,\n bytes data,\n string databaseID\n );\n\n function setMinter(address minter, bool status)\n public\n nonReentrant\n onlyOwner\n {\n isMinter[minter] = status;\n }\n\n function setSaleContract(address saleContract, bool status)\n public\n nonReentrant\n onlyOwner\n {\n isSaleContract[saleContract] = status;\n }\n\n function setAuthAddress(address _address) public nonReentrant onlyOwner {\n authAddress = _address;\n }\n\n function mintAndStake(\n uint32 quantity,\n uint256 price,\n uint256 startTime,\n address saleAddress,\n bytes calldata data,\n string calldata databaseID,\n uint8 v,\n bytes32 r,\n bytes32 s\n ) public nonReentrant {\n require(price \u003e= 0, \"Price less than 0\");\n require(quantity \u003e 0, \"Price greater than 1\");\n if (onlyMintersCanMint)\n require(isMinter[_msgSender()] == true, \"Caller is not a minter\");\n require(isSaleContract[saleAddress], \"Unrecognized sale contract.\");\n address signer = ecrecover(\n keccak256(\n abi.encode(\n \"NFTFM_mintAndStake\",\n _msgSender(),\n quantity,\n price,\n startTime,\n saleAddress,\n data\n )\n ),\n v, r, s\n );\n require(signer == authAddress, \"Invalid signature\");\n nftID++;\n owners[nftID] = _msgSender();\n artists[_msgSender()].push(nftID);\n _mint(saleAddress, nftID, quantity, \"initial mint\");\n INFTSale(saleAddress).stake(\n nftID,\n payable(_msgSender()),\n quantity,\n price,\n startTime,\n data\n );\n emit MintAndStake(\n nftID,\n quantity,\n price,\n startTime,\n saleAddress,\n data,\n databaseID\n );\n }\n\n function mint(\n address to,\n uint256 id,\n uint256 quantity\n ) public nonReentrant {\n if (onlyMintersCanMint)\n require(isMinter[_msgSender()] == true, \"Caller is not a minter\");\n require(owners[id] == _msgSender(), \"Caller does not own id\");\n _mint(to, id, quantity, \"the more the merrier!\");\n // TODO should additional minting also be sent to a sales contract?\n }\n\n function burn(uint256 id, uint256 quantity) public nonReentrant {\n _burn(_msgSender(), id, quantity);\n }\n\n function burnBatch(uint256[] memory ids, uint256[] memory quantitys)\n public\n nonReentrant\n {\n _burnBatch(_msgSender(), ids, quantitys);\n }\n\n function getArtistsNFTs(address _owner)\n public\n view\n returns (uint256[] memory)\n {\n return artists[_owner];\n }\n\n function getFullBalance(address user)\n public\n view\n returns (uint256[] memory, uint256[] memory)\n {\n uint256[] memory ids = new uint256[](nftID);\n uint256[] memory balances = new uint256[](nftID);\n for (uint256 id = 1; id \u003c= nftID; id++) {\n ids[id - 1] = id;\n balances[id - 1] = balanceOf(user, id);\n }\n return (ids, balances);\n }\n}\n"},"Ownable.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\nimport \"./Context.sol\";\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 address msgSender = _msgSender();\n _owner = msgSender;\n emit OwnershipTransferred(address(0), 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 emit OwnershipTransferred(_owner, address(0));\n _owner = 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 emit OwnershipTransferred(_owner, newOwner);\n _owner = newOwner;\n }\n}\n"},"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\u0027s contents, replace the bits taken up by the boolean, and then write\n // back. This is the compiler\u0027s 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\u0027s 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"},"SafeMath.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.8.0;\n\n// CAUTION\n// This version of SafeMath should only be used with Solidity 0.8 or later,\n// because it relies on the compiler\u0027s built in overflow checks.\n\n/**\n * @dev Wrappers over Solidity\u0027s arithmetic operations.\n *\n * NOTE: `SafeMath` is no longer needed starting with Solidity 0.8. The compiler\n * now has built in overflow checking.\n */\nlibrary SafeMath {\n /**\n * @dev Returns the addition of two unsigned integers, with an overflow flag.\n *\n * _Available since v3.4._\n */\n function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n unchecked {\n uint256 c = a + b;\n if (c \u003c a) return (false, 0);\n return (true, c);\n }\n }\n\n /**\n * @dev Returns the substraction of two unsigned integers, with an overflow flag.\n *\n * _Available since v3.4._\n */\n function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n unchecked {\n if (b \u003e a) return (false, 0);\n return (true, a - b);\n }\n }\n\n /**\n * @dev Returns the multiplication of two unsigned integers, with an overflow flag.\n *\n * _Available since v3.4._\n */\n function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n unchecked {\n // Gas optimization: this is cheaper than requiring \u0027a\u0027 not being zero, but the\n // benefit is lost if \u0027b\u0027 is also tested.\n // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522\n if (a == 0) return (true, 0);\n uint256 c = a * b;\n if (c / a != b) return (false, 0);\n return (true, c);\n }\n }\n\n /**\n * @dev Returns the division of two unsigned integers, with a division by zero flag.\n *\n * _Available since v3.4._\n */\n function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n unchecked {\n if (b == 0) return (false, 0);\n return (true, a / b);\n }\n }\n\n /**\n * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.\n *\n * _Available since v3.4._\n */\n function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n unchecked {\n if (b == 0) return (false, 0);\n return (true, a % b);\n }\n }\n\n /**\n * @dev Returns the addition of two unsigned integers, reverting on\n * overflow.\n *\n * Counterpart to Solidity\u0027s `+` operator.\n *\n * Requirements:\n *\n * - Addition cannot overflow.\n */\n function add(uint256 a, uint256 b) internal pure returns (uint256) {\n return a + b;\n }\n\n /**\n * @dev Returns the subtraction of two unsigned integers, reverting on\n * overflow (when the result is negative).\n *\n * Counterpart to Solidity\u0027s `-` operator.\n *\n * Requirements:\n *\n * - Subtraction cannot overflow.\n */\n function sub(uint256 a, uint256 b) internal pure returns (uint256) {\n return a - b;\n }\n\n /**\n * @dev Returns the multiplication of two unsigned integers, reverting on\n * overflow.\n *\n * Counterpart to Solidity\u0027s `*` operator.\n *\n * Requirements:\n *\n * - Multiplication cannot overflow.\n */\n function mul(uint256 a, uint256 b) internal pure returns (uint256) {\n return a * b;\n }\n\n /**\n * @dev Returns the integer division of two unsigned integers, reverting on\n * division by zero. The result is rounded towards zero.\n *\n * Counterpart to Solidity\u0027s `/` operator.\n *\n * Requirements:\n *\n * - The divisor cannot be zero.\n */\n function div(uint256 a, uint256 b) internal pure returns (uint256) {\n return a / b;\n }\n\n /**\n * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\n * reverting when dividing by zero.\n *\n * Counterpart to Solidity\u0027s `%` operator. This function uses a `revert`\n * opcode (which leaves remaining gas untouched) while Solidity uses an\n * invalid opcode to revert (consuming all remaining gas).\n *\n * Requirements:\n *\n * - The divisor cannot be zero.\n */\n function mod(uint256 a, uint256 b) internal pure returns (uint256) {\n return a % b;\n }\n\n /**\n * @dev Returns the subtraction of two unsigned integers, reverting with custom message on\n * overflow (when the result is negative).\n *\n * CAUTION: This function is deprecated because it requires allocating memory for the error\n * message unnecessarily. For custom revert reasons use {trySub}.\n *\n * Counterpart to Solidity\u0027s `-` operator.\n *\n * Requirements:\n *\n * - Subtraction cannot overflow.\n */\n function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n unchecked {\n require(b \u003c= a, errorMessage);\n return a - b;\n }\n }\n\n /**\n * @dev Returns the integer division of two unsigned integers, reverting with custom message on\n * division by zero. The result is rounded towards zero.\n *\n * Counterpart to Solidity\u0027s `%` operator. This function uses a `revert`\n * opcode (which leaves remaining gas untouched) while Solidity uses an\n * invalid opcode to revert (consuming all remaining gas).\n *\n * Counterpart to Solidity\u0027s `/` operator. Note: this function uses a\n * `revert` opcode (which leaves remaining gas untouched) while Solidity\n * uses an invalid opcode to revert (consuming all remaining gas).\n *\n * Requirements:\n *\n * - The divisor cannot be zero.\n */\n function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n unchecked {\n require(b \u003e 0, errorMessage);\n return a / b;\n }\n }\n\n /**\n * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\n * reverting with custom message when dividing by zero.\n *\n * CAUTION: This function is deprecated because it requires allocating memory for the error\n * message unnecessarily. For custom revert reasons use {tryMod}.\n *\n * Counterpart to Solidity\u0027s `%` operator. This function uses a `revert`\n * opcode (which leaves remaining gas untouched) while Solidity uses an\n * invalid opcode to revert (consuming all remaining gas).\n *\n * Requirements:\n *\n * - The divisor cannot be zero.\n */\n function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n unchecked {\n require(b \u003e 0, errorMessage);\n return a % b;\n }\n }\n}\n"}}