/** *Submitted for verification at arbiscan.io on 2021-09-13 */ // Sources flattened with hardhat v2.6.0 https://hardhat.org // File contracts/erc721.sol // SPDX-License-Identifier: MIT pragma solidity 0.8.4; /** * @dev ERC-721 non-fungible token standard. * See https://github.com/ethereum/EIPs/blob/master/EIPS/eip-721.md. */ interface ERC721 { /** * @dev Emits when ownership of any NFT changes by any mechanism. This event emits when NFTs are * created (`from` == 0) and destroyed (`to` == 0). Exception: during contract creation, any * number of NFTs may be created and assigned without emitting Transfer. At the time of any * transfer, the approved address for that NFT (if any) is reset to none. */ event Transfer( address indexed _from, address indexed _to, uint256 indexed _tokenId ); /** * @dev This emits when the approved address for an NFT is changed or reaffirmed. The zero * address indicates there is no approved address. When a Transfer event emits, this also * indicates that the approved address for that NFT (if any) is reset to none. */ event Approval( address indexed _owner, address indexed _approved, uint256 indexed _tokenId ); /** * @dev This emits when an operator is enabled or disabled for an owner. The operator can manage * all NFTs of the owner. */ event ApprovalForAll( address indexed _owner, address indexed _operator, bool _approved ); /** * @notice Throws unless `msg.sender` is the current owner, an authorized operator, or the * approved address for this NFT. Throws if `_from` is not the current owner. Throws if `_to` is * the zero address. Throws if `_tokenId` is not a valid NFT. When transfer is complete, this * function checks if `_to` is a smart contract (code size > 0). If so, it calls * `onERC721Received` on `_to` and throws if the return value is not * `bytes4(keccak256("onERC721Received(address,uint256,bytes)"))`. * @dev Transfers the ownership of an NFT from one address to another address. This function can * be changed to payable. * @param _from The current owner of the NFT. * @param _to The new owner. * @param _tokenId The NFT to transfer. * @param _data Additional data with no specified format, sent in call to `_to`. */ function safeTransferFrom( address _from, address _to, uint256 _tokenId, bytes calldata _data ) external; /** * @notice This works identically to the other function with an extra data parameter, except this * function just sets data to "" * @dev Transfers the ownership of an NFT from one address to another address. This function can * be changed to payable. * @param _from The current owner of the NFT. * @param _to The new owner. * @param _tokenId The NFT to transfer. */ function safeTransferFrom( address _from, address _to, uint256 _tokenId ) external; /** * @notice The caller is responsible to confirm that `_to` is capable of receiving NFTs or else * they may be permanently lost. * @dev Throws unless `msg.sender` is the current owner, an authorized operator, or the approved * address for this NFT. Throws if `_from` is not the current owner. Throws if `_to` is the zero * address. Throws if `_tokenId` is not a valid NFT. This function can be changed to payable. * @param _from The current owner of the NFT. * @param _to The new owner. * @param _tokenId The NFT to transfer. */ function transferFrom( address _from, address _to, uint256 _tokenId ) external; /** * @notice The zero address indicates there is no approved address. Throws unless `msg.sender` is * the current NFT owner, or an authorized operator of the current owner. * @param _approved The new approved NFT controller. * @dev Set or reaffirm the approved address for an NFT. This function can be changed to payable. * @param _tokenId The NFT to approve. */ function approve(address _approved, uint256 _tokenId) external; /** * @notice The contract MUST allow multiple operators per owner. * @dev Enables or disables approval for a third party ("operator") to manage all of * `msg.sender`'s assets. It also emits the ApprovalForAll event. * @param _operator Address to add to the set of authorized operators. * @param _approved True if the operators is approved, false to revoke approval. */ function setApprovalForAll(address _operator, bool _approved) external; /** * @dev Returns the number of NFTs owned by `_owner`. NFTs assigned to the zero address are * considered invalid, and this function throws for queries about the zero address. * @notice Count all NFTs assigned to an owner. * @param _owner Address for whom to query the balance. * @return Balance of _owner. */ function balanceOf(address _owner) external view returns (uint256); /** * @notice Find the owner of an NFT. * @dev Returns the address of the owner of the NFT. NFTs assigned to the zero address are * considered invalid, and queries about them do throw. * @param _tokenId The identifier for an NFT. * @return Address of _tokenId owner. */ function ownerOf(uint256 _tokenId) external view returns (address); /** * @notice Throws if `_tokenId` is not a valid NFT. * @dev Get the approved address for a single NFT. * @param _tokenId The NFT to find the approved address for. * @return Address that _tokenId is approved for. */ function getApproved(uint256 _tokenId) external view returns (address); /** * @notice Query if an address is an authorized operator for another address. * @dev Returns true if `_operator` is an approved operator for `_owner`, false otherwise. * @param _owner The address that owns the NFTs. * @param _operator The address that acts on behalf of the owner. * @return True if approved for all, false otherwise. */ function isApprovedForAll(address _owner, address _operator) external view returns (bool); } // File contracts/erc721-token-receiver.solpragma solidity 0.8.4; /** * @dev ERC-721 interface for accepting safe transfers. * See https://github.com/ethereum/EIPs/blob/master/EIPS/eip-721.md. */ interface ERC721TokenReceiver { /** * @notice The contract address is always the message sender. A wallet/broker/auction application * MUST implement the wallet interface if it will accept safe transfers. * @dev Handle the receipt of a NFT. The ERC721 smart contract calls this function on the * recipient after a `transfer`. This function MAY throw to revert and reject the transfer. Return * of other than the magic value MUST result in the transaction being reverted. * Returns `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))` unless throwing. * @param _operator The address which called `safeTransferFrom` function. * @param _from The address which previously owned the token. * @param _tokenId The NFT identifier which is being transferred. * @param _data Additional data with no specified format. * @return Returns `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`. */ function onERC721Received( address _operator, address _from, uint256 _tokenId, bytes calldata _data ) external returns (bytes4); } // File contracts/erc165.solpragma solidity 0.8.4; /** * @dev A standard for detecting smart contract interfaces. * See: https://eips.ethereum.org/EIPS/eip-165. */ interface ERC165 { /** * @dev Checks if the smart contract includes a specific interface. * This function uses less than 30,000 gas. * @param _interfaceID The interface identifier, as specified in ERC-165. * @return True if _interfaceID is supported, false otherwise. */ function supportsInterface(bytes4 _interfaceID) external view returns (bool); } // File contracts/supports-interface.sol pragma solidity 0.8.4; /** * @dev Implementation of standard for detect smart contract interfaces. */ contract SupportsInterface is ERC165 { /** * @dev Mapping of supported intefraces. You must not set element 0xffffffff to true. */ mapping(bytes4 => bool) internal supportedInterfaces; /** * @dev Contract constructor. */ constructor() { supportedInterfaces[0x01ffc9a7] = true; // ERC165 } /** * @dev Function to check which interfaces are suported by this contract. * @param _interfaceID Id of the interface. * @return True if _interfaceID is supported, false otherwise. */ function supportsInterface(bytes4 _interfaceID) external view override returns (bool) { return supportedInterfaces[_interfaceID]; } } // File contracts/address-utils.sol pragma solidity 0.8.4; /** * @notice Based on: * https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/Address.sol * Requires EIP-1052. * @dev Utility library of inline functions on addresses. */ library AddressUtils { /** * @dev Returns whether the target address is a contract. * @param _addr Address to check. * @return addressCheck True if _addr is a contract, false if not. */ function isContract(address _addr) internal view returns (bool addressCheck) { // This method relies in extcodesize, which returns 0 for contracts in // construction, since the code is only stored at the end of the // constructor execution. // According to EIP-1052, 0x0 is the value returned for not-yet created accounts // and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned // for accounts without code, i.e. `keccak256('')` bytes32 codehash; bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470; assembly { codehash := extcodehash(_addr) } // solhint-disable-line addressCheck = (codehash != 0x0 && codehash != accountHash); } } // File contracts/nf-token.sol pragma solidity 0.8.4; /** * @dev Implementation of ERC-721 non-fungible token standard. */ contract NFToken is ERC721, SupportsInterface { using AddressUtils for address; /** * @dev List of revert message codes. Implementing dApp should handle showing the correct message. * Based on 0xcert framework error codes. */ string constant ZERO_ADDRESS = '003001'; string constant NOT_VALID_NFT = '003002'; string constant NOT_OWNER_OR_OPERATOR = '003003'; string constant NOT_OWNER_APPROVED_OR_OPERATOR = '003004'; string constant NOT_ABLE_TO_RECEIVE_NFT = '003005'; string constant NFT_ALREADY_EXISTS = '003006'; string constant NOT_OWNER = '003007'; string constant IS_OWNER = '003008'; /** * @dev Magic value of a smart contract that can receive NFT. * Equal to: bytes4(keccak256("onERC721Received(address,address,uint256,bytes)")). */ bytes4 internal constant MAGIC_ON_ERC721_RECEIVED = 0x150b7a02; /** * @dev A mapping from NFT ID to the address that owns it. */ mapping(uint256 => address) internal idToOwner; /** * @dev Mapping from NFT ID to approved address. */ mapping(uint256 => address) internal idToApproval; /** * @dev Mapping from owner address to count of their tokens. */ mapping(address => uint256) private ownerToNFTokenCount; /** * @dev Mapping from owner address to mapping of operator addresses. */ mapping(address => mapping(address => bool)) internal ownerToOperators; /** * @dev Guarantees that the msg.sender is an owner or operator of the given NFT. * @param _tokenId ID of the NFT to validate. */ modifier canOperate(uint256 _tokenId) { address tokenOwner = idToOwner[_tokenId]; require( tokenOwner == msg.sender || ownerToOperators[tokenOwner][msg.sender], NOT_OWNER_OR_OPERATOR ); _; } /** * @dev Guarantees that the msg.sender is allowed to transfer NFT. * @param _tokenId ID of the NFT to transfer. */ modifier canTransfer(uint256 _tokenId) { address tokenOwner = idToOwner[_tokenId]; require( tokenOwner == msg.sender || idToApproval[_tokenId] == msg.sender || ownerToOperators[tokenOwner][msg.sender], NOT_OWNER_APPROVED_OR_OPERATOR ); _; } /** * @dev Guarantees that _tokenId is a valid Token. * @param _tokenId ID of the NFT to validate. */ modifier validNFToken(uint256 _tokenId) { require(idToOwner[_tokenId] != address(0), NOT_VALID_NFT); _; } /** * @dev Contract constructor. */ constructor() { supportedInterfaces[0x80ac58cd] = true; // ERC721 } /** * @notice Throws unless `msg.sender` is the current owner, an authorized operator, or the * approved address for this NFT. Throws if `_from` is not the current owner. Throws if `_to` is * the zero address. Throws if `_tokenId` is not a valid NFT. When transfer is complete, this * function checks if `_to` is a smart contract (code size > 0). If so, it calls * `onERC721Received` on `_to` and throws if the return value is not * `bytes4(keccak256("onERC721Received(address,uint256,bytes)"))`. * @dev Transfers the ownership of an NFT from one address to another address. This function can * be changed to payable. * @param _from The current owner of the NFT. * @param _to The new owner. * @param _tokenId The NFT to transfer. * @param _data Additional data with no specified format, sent in call to `_to`. */ function safeTransferFrom( address _from, address _to, uint256 _tokenId, bytes calldata _data ) external override { _safeTransferFrom(_from, _to, _tokenId, _data); } /** * @notice This works identically to the other function with an extra data parameter, except this * function just sets data to "". * @dev Transfers the ownership of an NFT from one address to another address. This function can * be changed to payable. * @param _from The current owner of the NFT. * @param _to The new owner. * @param _tokenId The NFT to transfer. */ function safeTransferFrom( address _from, address _to, uint256 _tokenId ) external override { _safeTransferFrom(_from, _to, _tokenId, ''); } /** * @notice The caller is responsible to confirm that `_to` is capable of receiving NFTs or else * they may be permanently lost. * @dev Throws unless `msg.sender` is the current owner, an authorized operator, or the approved * address for this NFT. Throws if `_from` is not the current owner. Throws if `_to` is the zero * address. Throws if `_tokenId` is not a valid NFT. This function can be changed to payable. * @param _from The current owner of the NFT. * @param _to The new owner. * @param _tokenId The NFT to transfer. */ function transferFrom( address _from, address _to, uint256 _tokenId ) external override canTransfer(_tokenId) validNFToken(_tokenId) { address tokenOwner = idToOwner[_tokenId]; require(tokenOwner == _from, NOT_OWNER); require(_to != address(0), ZERO_ADDRESS); _transfer(_to, _tokenId); } /** * @notice The zero address indicates there is no approved address. Throws unless `msg.sender` is * the current NFT owner, or an authorized operator of the current owner. * @dev Set or reaffirm the approved address for an NFT. This function can be changed to payable. * @param _approved Address to be approved for the given NFT ID. * @param _tokenId ID of the token to be approved. */ function approve(address _approved, uint256 _tokenId) external override canOperate(_tokenId) validNFToken(_tokenId) { address tokenOwner = idToOwner[_tokenId]; require(_approved != tokenOwner, IS_OWNER); idToApproval[_tokenId] = _approved; emit Approval(tokenOwner, _approved, _tokenId); } /** * @notice This works even if sender doesn't own any tokens at the time. * @dev Enables or disables approval for a third party ("operator") to manage all of * `msg.sender`'s assets. It also emits the ApprovalForAll event. * @param _operator Address to add to the set of authorized operators. * @param _approved True if the operators is approved, false to revoke approval. */ function setApprovalForAll(address _operator, bool _approved) external override { ownerToOperators[msg.sender][_operator] = _approved; emit ApprovalForAll(msg.sender, _operator, _approved); } /** * @dev Returns the number of NFTs owned by `_owner`. NFTs assigned to the zero address are * considered invalid, and this function throws for queries about the zero address. * @param _owner Address for whom to query the balance. * @return Balance of _owner. */ function balanceOf(address _owner) external view override returns (uint256) { require(_owner != address(0), ZERO_ADDRESS); return _getOwnerNFTCount(_owner); } /** * @dev Returns the address of the owner of the NFT. NFTs assigned to the zero address are * considered invalid, and queries about them do throw. * @param _tokenId The identifier for an NFT. * @return _owner Address of _tokenId owner. */ function ownerOf(uint256 _tokenId) external view override returns (address _owner) { _owner = idToOwner[_tokenId]; require(_owner != address(0), NOT_VALID_NFT); } /** * @notice Throws if `_tokenId` is not a valid NFT. * @dev Get the approved address for a single NFT. * @param _tokenId ID of the NFT to query the approval of. * @return Address that _tokenId is approved for. */ function getApproved(uint256 _tokenId) external view override validNFToken(_tokenId) returns (address) { return idToApproval[_tokenId]; } /** * @dev Checks if `_operator` is an approved operator for `_owner`. * @param _owner The address that owns the NFTs. * @param _operator The address that acts on behalf of the owner. * @return True if approved for all, false otherwise. */ function isApprovedForAll(address _owner, address _operator) external view override returns (bool) { return ownerToOperators[_owner][_operator]; } /** * @notice Does NO checks. * @dev Actually performs the transfer. * @param _to Address of a new owner. * @param _tokenId The NFT that is being transferred. */ function _transfer(address _to, uint256 _tokenId) internal { address from = idToOwner[_tokenId]; _clearApproval(_tokenId); _removeNFToken(from, _tokenId); _addNFToken(_to, _tokenId); emit Transfer(from, _to, _tokenId); } /** * @notice This is an internal function which should be called from user-implemented external * mint function. Its purpose is to show and properly initialize data structures when using this * implementation. * @dev Mints a new NFT. * @param _to The address that will own the minted NFT. * @param _tokenId of the NFT to be minted by the msg.sender. */ function _mint(address _to, uint256 _tokenId) internal virtual { require(_to != address(0), ZERO_ADDRESS); require(idToOwner[_tokenId] == address(0), NFT_ALREADY_EXISTS); _addNFToken(_to, _tokenId); emit Transfer(address(0), _to, _tokenId); } /** * @notice This is an internal function which should be called from user-implemented external burn * function. Its purpose is to show and properly initialize data structures when using this * implementation. Also, note that this burn implementation allows the minter to re-mint a burned * NFT. * @dev Burns a NFT. * @param _tokenId ID of the NFT to be burned. */ function _burn(uint256 _tokenId) internal virtual validNFToken(_tokenId) { address tokenOwner = idToOwner[_tokenId]; _clearApproval(_tokenId); _removeNFToken(tokenOwner, _tokenId); emit Transfer(tokenOwner, address(0), _tokenId); } /** * @notice Use and override this function with caution. Wrong usage can have serious consequences. * @dev Removes a NFT from owner. * @param _from Address from which we want to remove the NFT. * @param _tokenId Which NFT we want to remove. */ function _removeNFToken(address _from, uint256 _tokenId) internal virtual { require(idToOwner[_tokenId] == _from, NOT_OWNER); ownerToNFTokenCount[_from] -= 1; delete idToOwner[_tokenId]; } /** * @notice Use and override this function with caution. Wrong usage can have serious consequences. * @dev Assigns a new NFT to owner. * @param _to Address to which we want to add the NFT. * @param _tokenId Which NFT we want to add. */ function _addNFToken(address _to, uint256 _tokenId) internal virtual { require(idToOwner[_tokenId] == address(0), NFT_ALREADY_EXISTS); idToOwner[_tokenId] = _to; ownerToNFTokenCount[_to] += 1; } /** * @dev Helper function that gets NFT count of owner. This is needed for overriding in enumerable * extension to remove double storage (gas optimization) of owner NFT count. * @param _owner Address for whom to query the count. * @return Number of _owner NFTs. */ function _getOwnerNFTCount(address _owner) internal view virtual returns (uint256) { return ownerToNFTokenCount[_owner]; } /** * @dev Actually perform the safeTransferFrom. * @param _from The current owner of the NFT. * @param _to The new owner. * @param _tokenId The NFT to transfer. * @param _data Additional data with no specified format, sent in call to `_to`. */ function _safeTransferFrom( address _from, address _to, uint256 _tokenId, bytes memory _data ) private canTransfer(_tokenId) validNFToken(_tokenId) { address tokenOwner = idToOwner[_tokenId]; require(tokenOwner == _from, NOT_OWNER); require(_to != address(0), ZERO_ADDRESS); _transfer(_to, _tokenId); if (_to.isContract()) { bytes4 retval = ERC721TokenReceiver(_to).onERC721Received( msg.sender, _from, _tokenId, _data ); require( retval == MAGIC_ON_ERC721_RECEIVED, NOT_ABLE_TO_RECEIVE_NFT ); } } /** * @dev Clears the current approval of a given NFT ID. * @param _tokenId ID of the NFT to be transferred. */ function _clearApproval(uint256 _tokenId) private { delete idToApproval[_tokenId]; } } // File contracts/erc721-enumerable.solpragma solidity 0.8.4; /** * @dev Optional enumeration extension for ERC-721 non-fungible token standard. * See https://github.com/ethereum/EIPs/blob/master/EIPS/eip-721.md. */ interface ERC721Enumerable { /** * @dev Returns a count of valid NFTs tracked by this contract, where each one of them has an * assigned and queryable owner not equal to the zero address. * @return Total supply of NFTs. */ function totalSupply() external view returns (uint256); /** * @dev Returns the token identifier for the `_index`th NFT. Sort order is not specified. * @param _index A counter less than `totalSupply()`. * @return Token id. */ function tokenByIndex(uint256 _index) external view returns (uint256); /** * @dev Returns the token identifier for the `_index`th NFT assigned to `_owner`. Sort order is * not specified. It throws if `_index` >= `balanceOf(_owner)` or if `_owner` is the zero address, * representing invalid NFTs. * @param _owner An address where we are interested in NFTs owned by them. * @param _index A counter less than `balanceOf(_owner)`. * @return Token id. */ function tokenOfOwnerByIndex(address _owner, uint256 _index) external view returns (uint256); } // File contracts/nf-token-enumerable.solpragma solidity 0.8.4; /** * @dev Optional enumeration implementation for ERC-721 non-fungible token standard. */ contract NFTokenEnumerable is NFToken, ERC721Enumerable { /** * @dev List of revert message codes. Implementing dApp should handle showing the correct message. * Based on 0xcert framework error codes. */ string constant INVALID_INDEX = '005007'; /** * @dev Array of all NFT IDs. */ uint256[] internal tokens; /** * @dev Mapping from token ID to its index in global tokens array. */ mapping(uint256 => uint256) internal idToIndex; /** * @dev Mapping from owner to list of owned NFT IDs. */ mapping(address => uint256[]) internal ownerToIds; /** * @dev Mapping from NFT ID to its index in the owner tokens list. */ mapping(uint256 => uint256) internal idToOwnerIndex; /** * @dev Contract constructor. */ constructor() { supportedInterfaces[0x780e9d63] = true; // ERC721Enumerable } /** * @dev Returns the count of all existing NFTokens. * @return Total supply of NFTs. */ function totalSupply() external view override returns (uint256) { return tokens.length; } /** * @dev Returns NFT ID by its index. * @param _index A counter less than `totalSupply()`. * @return Token id. */ function tokenByIndex(uint256 _index) external view override returns (uint256) { require(_index < tokens.length, INVALID_INDEX); return tokens[_index]; } /** * @dev returns the n-th NFT ID from a list of owner's tokens. * @param _owner Token owner's address. * @param _index Index number representing n-th token in owner's list of tokens. * @return Token id. */ function tokenOfOwnerByIndex(address _owner, uint256 _index) external view override returns (uint256) { require(_index < ownerToIds[_owner].length, INVALID_INDEX); return ownerToIds[_owner][_index]; } /** * @notice This is an internal function which should be called from user-implemented external * mint function. Its purpose is to show and properly initialize data structures when using this * implementation. * @dev Mints a new NFT. * @param _to The address that will own the minted NFT. * @param _tokenId of the NFT to be minted by the msg.sender. */ function _mint(address _to, uint256 _tokenId) internal virtual override { super._mint(_to, _tokenId); tokens.push(_tokenId); idToIndex[_tokenId] = tokens.length - 1; } /** * @notice This is an internal function which should be called from user-implemented external * burn function. Its purpose is to show and properly initialize data structures when using this * implementation. Also, note that this burn implementation allows the minter to re-mint a burned * NFT. * @dev Burns a NFT. * @param _tokenId ID of the NFT to be burned. */ function _burn(uint256 _tokenId) internal virtual override { super._burn(_tokenId); uint256 tokenIndex = idToIndex[_tokenId]; uint256 lastTokenIndex = tokens.length - 1; uint256 lastToken = tokens[lastTokenIndex]; tokens[tokenIndex] = lastToken; tokens.pop(); // This wastes gas if you are burning the last token but saves a little gas if you are not. idToIndex[lastToken] = tokenIndex; idToIndex[_tokenId] = 0; } /** * @notice Use and override this function with caution. Wrong usage can have serious consequences. * @dev Removes a NFT from an address. * @param _from Address from wich we want to remove the NFT. * @param _tokenId Which NFT we want to remove. */ function _removeNFToken(address _from, uint256 _tokenId) internal virtual override { require(idToOwner[_tokenId] == _from, NOT_OWNER); delete idToOwner[_tokenId]; uint256 tokenToRemoveIndex = idToOwnerIndex[_tokenId]; uint256 lastTokenIndex = ownerToIds[_from].length - 1; if (lastTokenIndex != tokenToRemoveIndex) { uint256 lastToken = ownerToIds[_from][lastTokenIndex]; ownerToIds[_from][tokenToRemoveIndex] = lastToken; idToOwnerIndex[lastToken] = tokenToRemoveIndex; } ownerToIds[_from].pop(); } /** * @notice Use and override this function with caution. Wrong usage can have serious consequences. * @dev Assigns a new NFT to an address. * @param _to Address to wich we want to add the NFT. * @param _tokenId Which NFT we want to add. */ function _addNFToken(address _to, uint256 _tokenId) internal virtual override { require(idToOwner[_tokenId] == address(0), NFT_ALREADY_EXISTS); idToOwner[_tokenId] = _to; ownerToIds[_to].push(_tokenId); idToOwnerIndex[_tokenId] = ownerToIds[_to].length - 1; } /** * @dev Helper function that gets NFT count of owner. This is needed for overriding in enumerable * extension to remove double storage(gas optimization) of owner NFT count. * @param _owner Address for whom to query the count. * @return Number of _owner NFTs. */ function _getOwnerNFTCount(address _owner) internal view virtual override returns (uint256) { return ownerToIds[_owner].length; } } // File contracts/erc721-metadata.sol pragma solidity 0.8.4; /** * @dev Optional metadata extension for ERC-721 non-fungible token standard. * See https://github.com/ethereum/EIPs/blob/master/EIPS/eip-721.md. */ interface ERC721Metadata { /** * @dev Returns a descriptive name for a collection of NFTs in this contract. * @return _name Representing name. */ function name() external view returns (string memory _name); /** * @dev Returns a abbreviated name for a collection of NFTs in this contract. * @return _symbol Representing symbol. */ function symbol() external view returns (string memory _symbol); /** * @dev Returns a distinct Uniform Resource Identifier (URI) for a given asset. It Throws if * `_tokenId` is not a valid NFT. URIs are defined in RFC3986. The URI may point to a JSON file * that conforms to the "ERC721 Metadata JSON Schema". * @return URI of _tokenId. */ function tokenURI(uint256 _tokenId) external view returns (string memory); } // File contracts/nf-token-metadata.sol pragma solidity 0.8.4; /** * @dev Optional metadata implementation for ERC-721 non-fungible token standard. */ contract NFTokenMetadata is NFToken, ERC721Metadata { /** * @dev A descriptive name for a collection of NFTs. */ string internal nftName; /** * @dev An abbreviated name for NFTokens. */ string internal nftSymbol; /** * @dev Mapping from NFT ID to metadata uri. */ mapping(uint256 => string) internal idToUri; /** * @notice When implementing this contract don't forget to set nftName and nftSymbol. * @dev Contract constructor. */ constructor() { supportedInterfaces[0x5b5e139f] = true; // ERC721Metadata } /** * @dev Returns a descriptive name for a collection of NFTokens. * @return _name Representing name. */ function name() external view override returns (string memory _name) { _name = nftName; } /** * @dev Returns an abbreviated name for NFTokens. * @return _symbol Representing symbol. */ function symbol() external view override returns (string memory _symbol) { _symbol = nftSymbol; } /** * @dev A distinct URI (RFC 3986) for a given NFT. * @param _tokenId Id for which we want uri. * @return URI of _tokenId. */ function tokenURI(uint256 _tokenId) external view override validNFToken(_tokenId) returns (string memory) { return idToUri[_tokenId]; } /** * @notice This is an internal function which should be called from user-implemented external * burn function. Its purpose is to show and properly initialize data structures when using this * implementation. Also, note that this burn implementation allows the minter to re-mint a burned * NFT. * @dev Burns a NFT. * @param _tokenId ID of the NFT to be burned. */ function _burn(uint256 _tokenId) internal virtual override { super._burn(_tokenId); delete idToUri[_tokenId]; } /** * @notice This is an internal function which should be called from user-implemented external * function. Its purpose is to show and properly initialize data structures when using this * implementation. * @dev Set a distinct URI (RFC 3986) for a given NFT ID. * @param _tokenId Id for which we want URI. * @param _uri String representing RFC 3986 URI. */ function _setTokenUri(uint256 _tokenId, string memory _uri) internal validNFToken(_tokenId) { idToUri[_tokenId] = _uri; } } // File contracts/NFTokenMetadataEnumerable.sol pragma solidity 0.8.4; /** * @dev Optional metadata implementation for ERC-721 non-fungible token standard. */ abstract contract NFTokenEnumerableMetadata is NFToken, ERC721Metadata, ERC721Enumerable { /** * @dev A descriptive name for a collection of NFTs. */ string internal nftName; /** * @dev An abbreviated name for NFTokens. */ string internal nftSymbol; /** * @dev Mapping from NFT ID to metadata uri. */ mapping(uint256 => string) internal idToUri; /** * @dev List of revert message codes. Implementing dApp should handle showing the correct message. * Based on 0xcert framework error codes. */ string constant INVALID_INDEX = '005007'; /** * @dev Array of all NFT IDs. */ uint256[] internal tokens; /** * @dev Mapping from token ID to its index in global tokens array. */ mapping(uint256 => uint256) internal idToIndex; /** * @dev Mapping from owner to list of owned NFT IDs. */ mapping(address => uint256[]) internal ownerToIds; /** * @dev Mapping from NFT ID to its index in the owner tokens list. */ mapping(uint256 => uint256) internal idToOwnerIndex; /** * @notice When implementing this contract don't forget to set nftName and nftSymbol. * @dev Contract constructor. */ constructor() { supportedInterfaces[0x780e9d63] = true; // ERC721Enumerable supportedInterfaces[0x5b5e139f] = true; // ERC721Metadata } /** * @dev Returns a descriptive name for a collection of NFTokens. * @return _name Representing name. */ function name() external view override returns (string memory _name) { _name = nftName; } /** * @dev Returns an abbreviated name for NFTokens. * @return _symbol Representing symbol. */ function symbol() external view override returns (string memory _symbol) { _symbol = nftSymbol; } /** * @dev A distinct URI (RFC 3986) for a given NFT. * @param _tokenId Id for which we want uri. * @return URI of _tokenId. */ function tokenURI(uint256 _tokenId) external view override validNFToken(_tokenId) returns (string memory) { return idToUri[_tokenId]; } /** * @notice This is an internal function which should be called from user-implemented external * function. Its purpose is to show and properly initialize data structures when using this * implementation. * @dev Set a distinct URI (RFC 3986) for a given NFT ID. * @param _tokenId Id for which we want URI. * @param _uri String representing RFC 3986 URI. */ function _setTokenUri(uint256 _tokenId, string memory _uri) internal validNFToken(_tokenId) { idToUri[_tokenId] = _uri; } /** * @dev Returns the count of all existing NFTokens. * @return Total supply of NFTs. */ function totalSupply() external view override returns (uint256) { return tokens.length; } /** * @dev Returns NFT ID by its index. * @param _index A counter less than `totalSupply()`. * @return Token id. */ function tokenByIndex(uint256 _index) external view override returns (uint256) { require(_index < tokens.length, INVALID_INDEX); return tokens[_index]; } /** * @dev returns the n-th NFT ID from a list of owner's tokens. * @param _owner Token owner's address. * @param _index Index number representing n-th token in owner's list of tokens. * @return Token id. */ function tokenOfOwnerByIndex(address _owner, uint256 _index) external view override returns (uint256) { require(_index < ownerToIds[_owner].length, INVALID_INDEX); return ownerToIds[_owner][_index]; } /** * @notice This is an internal function which should be called from user-implemented external * mint function. Its purpose is to show and properly initialize data structures when using this * implementation. * @dev Mints a new NFT. * @param _to The address that will own the minted NFT. * @param _tokenId of the NFT to be minted by the msg.sender. */ function _mint(address _to, uint256 _tokenId) internal virtual override { super._mint(_to, _tokenId); tokens.push(_tokenId); idToIndex[_tokenId] = tokens.length - 1; } /** * @notice This is an internal function which should be called from user-implemented external * burn function. Its purpose is to show and properly initialize data structures when using this * implementation. Also, note that this burn implementation allows the minter to re-mint a burned * NFT. * @dev Burns a NFT. * @param _tokenId ID of the NFT to be burned. */ function _burn(uint256 _tokenId) internal virtual override { super._burn(_tokenId); uint256 tokenIndex = idToIndex[_tokenId]; uint256 lastTokenIndex = tokens.length - 1; uint256 lastToken = tokens[lastTokenIndex]; tokens[tokenIndex] = lastToken; tokens.pop(); delete idToUri[_tokenId]; // This wastes gas if you are burning the last token but saves a little gas if you are not. idToIndex[lastToken] = tokenIndex; idToIndex[_tokenId] = 0; } /** * @notice Use and override this function with caution. Wrong usage can have serious consequences. * @dev Removes a NFT from an address. * @param _from Address from wich we want to remove the NFT. * @param _tokenId Which NFT we want to remove. */ function _removeNFToken(address _from, uint256 _tokenId) internal virtual override { require(idToOwner[_tokenId] == _from, NOT_OWNER); delete idToOwner[_tokenId]; uint256 tokenToRemoveIndex = idToOwnerIndex[_tokenId]; uint256 lastTokenIndex = ownerToIds[_from].length - 1; if (lastTokenIndex != tokenToRemoveIndex) { uint256 lastToken = ownerToIds[_from][lastTokenIndex]; ownerToIds[_from][tokenToRemoveIndex] = lastToken; idToOwnerIndex[lastToken] = tokenToRemoveIndex; } ownerToIds[_from].pop(); } /** * @notice Use and override this function with caution. Wrong usage can have serious consequences. * @dev Assigns a new NFT to an address. * @param _to Address to wich we want to add the NFT. * @param _tokenId Which NFT we want to add. */ function _addNFToken(address _to, uint256 _tokenId) internal virtual override { require(idToOwner[_tokenId] == address(0), NFT_ALREADY_EXISTS); idToOwner[_tokenId] = _to; ownerToIds[_to].push(_tokenId); idToOwnerIndex[_tokenId] = ownerToIds[_to].length - 1; } /** * @dev Helper function that gets NFT count of owner. This is needed for overriding in enumerable * extension to remove double storage(gas optimization) of owner NFT count. * @param _owner Address for whom to query the count. * @return Number of _owner NFTs. */ function _getOwnerNFTs(address _owner) internal view virtual returns (uint256[] memory) { return ownerToIds[_owner]; } /** * @dev Helper function that gets NFT count of owner. This is needed for overriding in enumerable * extension to remove double storage(gas optimization) of owner NFT count. * @param _owner Address for whom to query the count. * @return Number of _owner NFTs. */ function _getOwnerNFTCount(address _owner) internal view virtual override returns (uint256) { return ownerToIds[_owner].length; } } // File @openzeppelin/contracts/utils/Context.sol@v4.3.1pragma solidity 0.8.4; /** * @dev Provides information about the current execution context, including the * sender of the transaction and its data. While these are generally available * via msg.sender and msg.data, they should not be accessed in such a direct * manner, since when dealing with meta-transactions the account sending and * paying for execution may not be the actual sender (as far as an application * is concerned). * * This contract is only required for intermediate, library-like contracts. */ abstract contract Context { function _msgSender() internal view virtual returns (address) { return msg.sender; } function _msgData() internal view virtual returns (bytes calldata) { return msg.data; } } // File @openzeppelin/contracts/access/Ownable.sol@v4.3.1pragma solidity 0.8.4; /** * @dev Contract module which provides a basic access control mechanism, where * there is an account (an owner) that can be granted exclusive access to * specific functions. * * By default, the owner account will be the one that deploys the contract. This * can later be changed with {transferOwnership}. * * This module is used through inheritance. It will make available the modifier * `onlyOwner`, which can be applied to your functions to restrict their use to * the owner. */ abstract contract Ownable is Context { address private _owner; event OwnershipTransferred( address indexed previousOwner, address indexed newOwner ); /** * @dev Initializes the contract setting the deployer as the initial owner. */ constructor() { _setOwner(_msgSender()); } /** * @dev Returns the address of the current owner. */ function owner() public view virtual returns (address) { return _owner; } /** * @dev Throws if called by any account other than the owner. */ modifier onlyOwner() { require(owner() == _msgSender(), 'Ownable: caller is not the owner'); _; } /** * @dev Leaves the contract without owner. It will not be possible to call * `onlyOwner` functions anymore. Can only be called by the current owner. * * NOTE: Renouncing ownership will leave the contract without an owner, * thereby removing any functionality that is only available to the owner. */ function renounceOwnership() public virtual onlyOwner { _setOwner(address(0)); } /** * @dev Transfers ownership of the contract to a new account (`newOwner`). * Can only be called by the current owner. */ function transferOwnership(address newOwner) public virtual onlyOwner { require( newOwner != address(0), 'Ownable: new owner is the zero address' ); _setOwner(newOwner); } function _setOwner(address newOwner) private { address oldOwner = _owner; _owner = newOwner; emit OwnershipTransferred(oldOwner, newOwner); } } // File @openzeppelin/contracts/utils/math/SafeMath.sol@v4.3.1 pragma solidity 0.8.4; // CAUTION // This version of SafeMath should only be used with Solidity 0.8 or later, // because it relies on the compiler's built in overflow checks. /** * @dev Wrappers over Solidity's arithmetic operations. * * NOTE: `SafeMath` is no longer needed starting with Solidity 0.8. The compiler * now has built in overflow checking. */ library SafeMath { /** * @dev Returns the addition of two unsigned integers, with an overflow flag. * * _Available since v3.4._ */ function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) { unchecked { uint256 c = a + b; if (c < a) return (false, 0); return (true, c); } } /** * @dev Returns the substraction of two unsigned integers, with an overflow flag. * * _Available since v3.4._ */ function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) { unchecked { if (b > a) return (false, 0); return (true, a - b); } } /** * @dev Returns the multiplication of two unsigned integers, with an overflow flag. * * _Available since v3.4._ */ function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) { unchecked { // Gas optimization: this is cheaper than requiring 'a' not being zero, but the // benefit is lost if 'b' is also tested. // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522 if (a == 0) return (true, 0); uint256 c = a * b; if (c / a != b) return (false, 0); return (true, c); } } /** * @dev Returns the division of two unsigned integers, with a division by zero flag. * * _Available since v3.4._ */ function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) { unchecked { if (b == 0) return (false, 0); return (true, a / b); } } /** * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag. * * _Available since v3.4._ */ function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) { unchecked { if (b == 0) return (false, 0); return (true, a % b); } } /** * @dev Returns the addition of two unsigned integers, reverting on * overflow. * * Counterpart to Solidity's `+` operator. * * Requirements: * * - Addition cannot overflow. */ function add(uint256 a, uint256 b) internal pure returns (uint256) { return a + b; } /** * @dev Returns the subtraction of two unsigned integers, reverting on * overflow (when the result is negative). * * Counterpart to Solidity's `-` operator. * * Requirements: * * - Subtraction cannot overflow. */ function sub(uint256 a, uint256 b) internal pure returns (uint256) { return a - b; } /** * @dev Returns the multiplication of two unsigned integers, reverting on * overflow. * * Counterpart to Solidity's `*` operator. * * Requirements: * * - Multiplication cannot overflow. */ function mul(uint256 a, uint256 b) internal pure returns (uint256) { return a * b; } /** * @dev Returns the integer division of two unsigned integers, reverting on * division by zero. The result is rounded towards zero. * * Counterpart to Solidity's `/` operator. * * Requirements: * * - The divisor cannot be zero. */ function div(uint256 a, uint256 b) internal pure returns (uint256) { return a / b; } /** * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo), * reverting when dividing by zero. * * Counterpart to Solidity's `%` operator. This function uses a `revert` * opcode (which leaves remaining gas untouched) while Solidity uses an * invalid opcode to revert (consuming all remaining gas). * * Requirements: * * - The divisor cannot be zero. */ function mod(uint256 a, uint256 b) internal pure returns (uint256) { return a % b; } /** * @dev Returns the subtraction of two unsigned integers, reverting with custom message on * overflow (when the result is negative). * * CAUTION: This function is deprecated because it requires allocating memory for the error * message unnecessarily. For custom revert reasons use {trySub}. * * Counterpart to Solidity's `-` operator. * * Requirements: * * - Subtraction cannot overflow. */ function sub( uint256 a, uint256 b, string memory errorMessage ) internal pure returns (uint256) { unchecked { require(b <= a, errorMessage); return a - b; } } /** * @dev Returns the integer division of two unsigned integers, reverting with custom message on * division by zero. The result is rounded towards zero. * * Counterpart to Solidity's `/` operator. Note: this function uses a * `revert` opcode (which leaves remaining gas untouched) while Solidity * uses an invalid opcode to revert (consuming all remaining gas). * * Requirements: * * - The divisor cannot be zero. */ function div( uint256 a, uint256 b, string memory errorMessage ) internal pure returns (uint256) { unchecked { require(b > 0, errorMessage); return a / b; } } /** * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo), * reverting with custom message when dividing by zero. * * CAUTION: This function is deprecated because it requires allocating memory for the error * message unnecessarily. For custom revert reasons use {tryMod}. * * Counterpart to Solidity's `%` operator. This function uses a `revert` * opcode (which leaves remaining gas untouched) while Solidity uses an * invalid opcode to revert (consuming all remaining gas). * * Requirements: * * - The divisor cannot be zero. */ function mod( uint256 a, uint256 b, string memory errorMessage ) internal pure returns (uint256) { unchecked { require(b > 0, errorMessage); return a % b; } } } // File contracts/CeloPunks.sol pragma solidity 0.8.4; contract CeloPunks is NFTokenEnumerableMetadata, Ownable { using SafeMath for uint256; // TODO: Change the price uint256 public price = 0.01 ether; uint256 public maxSupply = 10_000; string private seed; uint256 public maxMintNFT = 15; uint256 public royaltyFee = 20; string public baseUri = 'https://ipfs.io/ipfs/QmWn3sCZLwyTzpT2vQL9aG9W8Uz5N2y6vaf7T2S7EFfE9s/'; mapping (uint256 => address) public originalMinter; mapping (address => uint256) public amountMintedPerAddress; mapping (address => bool) public didPremint; mapping (address => uint256) public marketingWallets; event PriceUpdated(uint256 newPrice); event MaxSupplyUpdated(uint256 newMaxSupply); event BaseUriUpdated(string newBaseUri); event royaltyFeeUpdated(uint256 royaltyFee); // TODO: Change the name constructor(string memory _seed) { nftName = 'CeloPunksTest'; nftSymbol = 'CTEST'; seed = _seed; marketingWallets[0xB8b8847132b0A94aAda60eED9685517dcCC98556] = 25; marketingWallets[0xC9e40Ba93Ce3c949709e36e24bF7D1f2eeda307E] = 8; marketingWallets[0x480Eaa880928d935595727331ff1D3C47E7742Cf] = 9; marketingWallets[0x474C5e74Ff9770dc1271301197E357CC1115dF67] = 24; marketingWallets[0x13b3287C8d163ea2cE04d6A2DF3598c72BE301ba] = 24; marketingWallets[msg.sender] = 10; } function premint() external { require(marketingWallets[msg.sender] > 0, 'No premint for this address'); require(!didPremint[msg.sender], 'Already did premint'); // Premint for influencers didPremint[msg.sender] = true; for (uint256 j=0; j < marketingWallets[msg.sender]; j++) { uint256 currentSupply = this.totalSupply(); uint256 tokenId = currentSupply; address to = msg.sender; super._mint(to, tokenId); bytes32 metadataHash = keccak256(abi.encodePacked("celo", toString(tokenId), ".json")); super._setTokenUri( tokenId, string(abi.encodePacked(baseUri, metadataHash, '.json')) ); originalMinter[tokenId] = msg.sender; } } function mint() external payable { // TODO: Uncomment this // require(block.timestamp > 1633370400, 'Please wait until minting starts') require(msg.value >= price, 'Amount is less than price'); require(maxSupply > this.totalSupply(), 'Sold out'); uint256 count = msg.value / price; require(maxSupply > this.totalSupply() + count, 'Almost sold out, please mint less punks'); require(maxMintNFT > amountMintedPerAddress[msg.sender] + count, 'Mint account limit reached. Please try a lower number'); for (uint256 i = 0; i < count; i++) { uint256 currentSupply = this.totalSupply(); uint256 tokenId = currentSupply; address to = msg.sender; super._mint(to, tokenId); amountMintedPerAddress[msg.sender] += 1; super._setTokenUri( tokenId, string(abi.encodePacked(baseUri, toString(tokenId), '.json')) ); originalMinter[tokenId] = msg.sender; } } function getOwnerNFTs(address _owner) public view returns (uint256[] memory) { return super._getOwnerNFTs(_owner); } function withdraw() external onlyOwner { payable(msg.sender).transfer(address(this).balance); } function updatePrice(uint256 _newPrice) public onlyOwner { price = _newPrice; emit PriceUpdated(_newPrice); } function updateMaxSupply(uint256 _maxSupply) public onlyOwner { maxSupply = _maxSupply; emit MaxSupplyUpdated(_maxSupply); } function updateroyaltyFee(uint _royaltyFee) public onlyOwner { require(_royaltyFee < 100); royaltyFee = _royaltyFee; emit royaltyFeeUpdated(_royaltyFee); } function updateBaseUri(string memory _baseUri) public onlyOwner { baseUri = _baseUri; emit BaseUriUpdated(_baseUri); } // EIP-2981 function royaltyInfo(uint256 _tokenId, uint256 _salePrice) external view returns (address receiver, uint256 royaltyRate) { address _receiver = originalMinter[_tokenId]; uint256 _royaltyFee = _salePrice - ((_salePrice * royaltyFee) / 1000); return(_receiver, _royaltyFee); } // TODO: Remove this function destroySmartContract(address payable _to) public { require(msg.sender == owner(), "You are not the owner"); selfdestruct(_to); } function toString(uint256 value) internal pure returns (string memory) { // Inspired by OraclizeAPI's implementation - MIT license // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol if (value == 0) { return '0'; } uint256 temp = value; uint256 digits; while (temp != 0) { digits++; temp /= 10; } bytes memory buffer = new bytes(digits); while (value != 0) { digits -= 1; buffer[digits] = bytes1(uint8(48 + uint256(value % 10))); value /= 10; } return string(buffer); } } // File @openzeppelin/contracts/token/ERC20/IERC20.sol@v4.3.1pragma solidity 0.8.4; /** * @dev Interface of the ERC20 standard as defined in the EIP. */ interface IERC20 { /** * @dev Returns the amount of tokens in existence. */ function totalSupply() external view returns (uint256); /** * @dev Returns the amount of tokens owned by `account`. */ function balanceOf(address account) external view returns (uint256); /** * @dev Moves `amount` tokens from the caller's account to `recipient`. * * Returns a boolean value indicating whether the operation succeeded. * * Emits a {Transfer} event. */ function transfer(address recipient, uint256 amount) external returns (bool); /** * @dev Returns the remaining number of tokens that `spender` will be * allowed to spend on behalf of `owner` through {transferFrom}. This is * zero by default. * * This value changes when {approve} or {transferFrom} are called. */ function allowance(address owner, address spender) external view returns (uint256); /** * @dev Sets `amount` as the allowance of `spender` over the caller's tokens. * * Returns a boolean value indicating whether the operation succeeded. * * IMPORTANT: Beware that changing an allowance with this method brings the risk * that someone may use both the old and the new allowance by unfortunate * transaction ordering. One possible solution to mitigate this race * condition is to first reduce the spender's allowance to 0 and set the * desired value afterwards: * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729 * * Emits an {Approval} event. */ function approve(address spender, uint256 amount) external returns (bool); /** * @dev Moves `amount` tokens from `sender` to `recipient` using the * allowance mechanism. `amount` is then deducted from the caller's * allowance. * * Returns a boolean value indicating whether the operation succeeded. * * Emits a {Transfer} event. */ function transferFrom( address sender, address recipient, uint256 amount ) external returns (bool); /** * @dev Emitted when `value` tokens are moved from one account (`from`) to * another (`to`). * * Note that `value` may be zero. */ event Transfer(address indexed from, address indexed to, uint256 value); /** * @dev Emitted when the allowance of a `spender` for an `owner` is set by * a call to {approve}. `value` is the new allowance. */ event Approval( address indexed owner, address indexed spender, uint256 value ); } // File @openzeppelin/contracts/utils/Address.sol@v4.3.1pragma solidity 0.8.4; /** * @dev Collection of functions related to the address type */ library Address { /** * @dev Returns true if `account` is a contract. * * [IMPORTANT] * ==== * It is unsafe to assume that an address for which this function returns * false is an externally-owned account (EOA) and not a contract. * * Among others, `isContract` will return false for the following * types of addresses: * * - an externally-owned account * - a contract in construction * - an address where a contract will be created * - an address where a contract lived, but was destroyed * ==== */ function isContract(address account) internal view returns (bool) { // This method relies on extcodesize, which returns 0 for contracts in // construction, since the code is only stored at the end of the // constructor execution. uint256 size; assembly { size := extcodesize(account) } return size > 0; } /** * @dev Replacement for Solidity's `transfer`: sends `amount` wei to * `recipient`, forwarding all available gas and reverting on errors. * * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost * of certain opcodes, possibly making contracts go over the 2300 gas limit * imposed by `transfer`, making them unable to receive funds via * `transfer`. {sendValue} removes this limitation. * * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more]. * * IMPORTANT: because control is transferred to `recipient`, care must be * taken to not create reentrancy vulnerabilities. Consider using * {ReentrancyGuard} or the * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern]. */ function sendValue(address payable recipient, uint256 amount) internal { require( address(this).balance >= amount, 'Address: insufficient balance' ); (bool success, ) = recipient.call{value: amount}(''); require( success, 'Address: unable to send value, recipient may have reverted' ); } /** * @dev Performs a Solidity function call using a low level `call`. A * plain `call` is an unsafe replacement for a function call: use this * function instead. * * If `target` reverts with a revert reason, it is bubbled up by this * function (like regular Solidity function calls). * * Returns the raw returned data. To convert to the expected return value, * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`]. * * Requirements: * * - `target` must be a contract. * - calling `target` with `data` must not revert. * * _Available since v3.1._ */ function functionCall(address target, bytes memory data) internal returns (bytes memory) { return functionCall(target, data, 'Address: low-level call failed'); } /** * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with * `errorMessage` as a fallback revert reason when `target` reverts. * * _Available since v3.1._ */ function functionCall( address target, bytes memory data, string memory errorMessage ) internal returns (bytes memory) { return functionCallWithValue(target, data, 0, errorMessage); } /** * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], * but also transferring `value` wei to `target`. * * Requirements: * * - the calling contract must have an ETH balance of at least `value`. * - the called Solidity function must be `payable`. * * _Available since v3.1._ */ function functionCallWithValue( address target, bytes memory data, uint256 value ) internal returns (bytes memory) { return functionCallWithValue( target, data, value, 'Address: low-level call with value failed' ); } /** * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but * with `errorMessage` as a fallback revert reason when `target` reverts. * * _Available since v3.1._ */ function functionCallWithValue( address target, bytes memory data, uint256 value, string memory errorMessage ) internal returns (bytes memory) { require( address(this).balance >= value, 'Address: insufficient balance for call' ); require(isContract(target), 'Address: call to non-contract'); (bool success, bytes memory returndata) = target.call{value: value}( data ); return verifyCallResult(success, returndata, errorMessage); } /** * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], * but performing a static call. * * _Available since v3.3._ */ function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) { return functionStaticCall( target, data, 'Address: low-level static call failed' ); } /** * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`], * but performing a static call. * * _Available since v3.3._ */ function functionStaticCall( address target, bytes memory data, string memory errorMessage ) internal view returns (bytes memory) { require(isContract(target), 'Address: static call to non-contract'); (bool success, bytes memory returndata) = target.staticcall(data); return verifyCallResult(success, returndata, errorMessage); } /** * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], * but performing a delegate call. * * _Available since v3.4._ */ function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) { return functionDelegateCall( target, data, 'Address: low-level delegate call failed' ); } /** * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`], * but performing a delegate call. * * _Available since v3.4._ */ function functionDelegateCall( address target, bytes memory data, string memory errorMessage ) internal returns (bytes memory) { require(isContract(target), 'Address: delegate call to non-contract'); (bool success, bytes memory returndata) = target.delegatecall(data); return verifyCallResult(success, returndata, errorMessage); } /** * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the * revert reason using the provided one. * * _Available since v4.3._ */ function verifyCallResult( bool success, bytes memory returndata, string memory errorMessage ) internal pure returns (bytes memory) { if (success) { return returndata; } else { // Look for revert reason and bubble it up if present if (returndata.length > 0) { // The easiest way to bubble the revert reason is using memory via assembly assembly { let returndata_size := mload(returndata) revert(add(32, returndata), returndata_size) } } else { revert(errorMessage); } } } } // File @openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol@v4.3.1 pragma solidity 0.8.4; /** * @title SafeERC20 * @dev Wrappers around ERC20 operations that throw on failure (when the token * contract returns false). Tokens that return no value (and instead revert or * throw on failure) are also supported, non-reverting calls are assumed to be * successful. * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract, * which allows you to call the safe operations as `token.safeTransfer(...)`, etc. */ library SafeERC20 { using Address for address; function safeTransfer( IERC20 token, address to, uint256 value ) internal { _callOptionalReturn( token, abi.encodeWithSelector(token.transfer.selector, to, value) ); } function safeTransferFrom( IERC20 token, address from, address to, uint256 value ) internal { _callOptionalReturn( token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value) ); } /** * @dev Deprecated. This function has issues similar to the ones found in * {IERC20-approve}, and its usage is discouraged. * * Whenever possible, use {safeIncreaseAllowance} and * {safeDecreaseAllowance} instead. */ function safeApprove( IERC20 token, address spender, uint256 value ) internal { // safeApprove should only be called when setting an initial allowance, // or when resetting it to zero. To increase and decrease it, use // 'safeIncreaseAllowance' and 'safeDecreaseAllowance' require( (value == 0) || (token.allowance(address(this), spender) == 0), 'SafeERC20: approve from non-zero to non-zero allowance' ); _callOptionalReturn( token, abi.encodeWithSelector(token.approve.selector, spender, value) ); } function safeIncreaseAllowance( IERC20 token, address spender, uint256 value ) internal { uint256 newAllowance = token.allowance(address(this), spender) + value; _callOptionalReturn( token, abi.encodeWithSelector( token.approve.selector, spender, newAllowance ) ); } function safeDecreaseAllowance( IERC20 token, address spender, uint256 value ) internal { unchecked { uint256 oldAllowance = token.allowance(address(this), spender); require( oldAllowance >= value, 'SafeERC20: decreased allowance below zero' ); uint256 newAllowance = oldAllowance - value; _callOptionalReturn( token, abi.encodeWithSelector( token.approve.selector, spender, newAllowance ) ); } } /** * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement * on the return value: the return value is optional (but if data is returned, it must not be false). * @param token The token targeted by the call. * @param data The call data (encoded using abi.encode or one of its variants). */ function _callOptionalReturn(IERC20 token, bytes memory data) private { // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that // the target address contains contract code and also asserts for success in the low-level call. bytes memory returndata = address(token).functionCall( data, 'SafeERC20: low-level call failed' ); if (returndata.length > 0) { // Return data is optional require( abi.decode(returndata, (bool)), 'SafeERC20: ERC20 operation did not succeed' ); } } }