[ERC5635] NFTのライセンスを管理する仕組みを理解しよう！

pragma solidity ^0.6.0;
import "./IERC165.sol";

///
/// @notice Interface of NFT derivatives (dNFT) for the NFT Licensing Standard
/// @dev The ERC-165 identifier for this interface is 0xd584841c.
interface IERC5635DNFT is IERC165 {

    /// ERC165 bytes to add to interface array - set in parent contract
    /// implementing this standard
    ///
    /// bytes4(keccak256("IERC5635DNFT{}")) == 0xd584841c
    /// bytes4 private constant _INTERFACE_ID_IERC5635DNFT = 0xd584841c;
    /// _registerInterface(_INTERFACE_ID_IERC5635XDNFT);
    
    /// @notice Get the number of credentials.
    /// @param _tokenId - ID of the dNFT asset queried
    /// @return _number - the number of credentials 
    function numberOfCredentials(
		uint256 _tokenId
    ) external view returns (
        uint256 _number
    );

    /// @notice Called with the sale price to determine how much royalty is owed and to whom.
    /// @param _tokenId - ID of the dNFT asset queried
    /// @param _credentialId - ID of the licensing agreement credential, the max id is numberOfCredentials(_tokenId)-1
    /// @return _oNFT - the oNFT address where the licensing from
    /// @return _tokenID - the oNFT ID where the licensing from
    /// @return _registry - the address of registry which can verify this credential
    function authorizedBy(
        uint256 _tokenId,
        uint256 _credentialId
    ) external view returns (
        address _oNFT,
        uint256 _tokenId,
        address _registry
    );
    
}

interface IERC165 {
    /// @notice Query if a contract implements an interface
    /// @param interfaceID The interface identifier, as specified in ERC-165
    /// @dev Interface identification is specified in ERC-165. This function
    ///  uses less than 30,000 gas.
    /// @return `true` if the contract implements `interfaceID` and
    ///  `interfaceID` is not 0xffffffff, `false` otherwise
    function supportsInterface(bytes4 interfaceID) external view returns (bool);
}

function numberOfCredentials(
    uint256 _tokenId
) external view returns (
    uint256 _number
);

function authorizedBy(
    uint256 _tokenId,
    uint256 _credentialId
) external view returns (
    address _oNFT,
    uint256 _tokenId,
    address _registry
);

pragma solidity ^0.6.0;
import "./IERC165.sol";

///
/// @dev Interface of NFT derivatives (dNFT) for the NFT Licensing Standard
///  Note: the ERC-165 identifier for this interface is 0xb5065e9f
interface IERC5635Registry is IERC165 {

    /// ERC165 bytes to add to interface array - set in parent contract
    /// implementing this standard
    ///
    /// bytes4(keccak256("IERC5635Registry{}")) == 0xb5065e9f
    /// bytes4 private constant _INTERFACE_ID_IERC5635Registry = 0xb5065e9f;
    /// _registerInterface(_INTERFACE_ID_IERC5635Registry);

    // TODO: Is the syntax correct?
    enum LicensingAgreementType {
      NonExclusive,
      Exclusive,
      Sole
    } 


    /// @notice 
    /// @param _dNFT - 
    /// @param _dNFT_Id - 
    /// @param _oNFT - 
    /// @param _oNFT_Id - 
    /// @return _licensed - 
    /// @return _tokenID - the oNFT ID where the licensing from
    /// @return _registry - the address of registry which can verify this credential
    function isLicensed(
        address _dNFT,
        uint256 _dNFT_Id,
        address _oNFT,
        uint256 _oNFT_Id
    ) external view returns (
        bool _licensed
    );
    
    /// @return _licenseIdentifier - the identifier, e.g. `MIT` or `Apache`, similar to `SPDX-License-Identifier: MIT` in SPDX.
    function licensingInfo(
        address _dNFT,
        uint256 _dNFT_Id,
        address _oNFT,
        uint256 _oNFT_Id
    ) external view returns (
        bool _licensed,
        address _licensor,
        uint64 _timeOfSignature,
        uint64 _expiryTime,
        LicensingAgreementType _type,
        string _licenseName,
        string _licenseUri //
    );
    
    function royaltyRate(
        address _dNFT,
        uint256 _dNFT_Id,
        address _oNFT,
        uint256 _oNFT_Id
    ) external view returns (
        address beneficiary, 
        uint256 rate // The decimals is 9, means to divide the rate by 1,000,000,000
    );
}

enum LicensingAgreementType {
  NonExclusive,
  Exclusive,
  Sole
}

function isLicensed(
    address _dNFT,
    uint256 _dNFT_Id,
    address _oNFT,
    uint256 _oNFT_Id
) external view returns (bool _licensed);

function licensingInfo(
    address _dNFT,
    uint256 _dNFT_Id,
    address _oNFT,
    uint256 _oNFT_Id
) external view returns (
    bool _licensed,
    address _licensor,
    uint64 _timeOfSignature,
    uint64 _expiryTime,
    LicensingAgreementType _type,
    string _licenseName,
    string _licenseUri
);

function royaltyRate(
    address _dNFT,
    uint256 _dNFT_Id,
    address _oNFT,
    uint256 _oNFT_Id
) external view returns (
    address beneficiary, 
    uint256 rate
);

pragma solidity ^0.6.0;
import "./IERC165.sol";

///
///
interface IERC5635Licensing is IERC165, IERC5635Registry {

    event Licence(address indexed _oNFT, uint256 indexed _oNFT_Id, address indexed _dNFT, uint256 indexed _dNFT_Id, uint64 _expiryTime, LicensingAgreementType _type, string _licenseName, string _licenseUri);

    event Approval(address indexed _oNFT, address indexed _owner, address indexed _approved, uint256 indexed _tokenId);
    
    event ApprovalForAll(address indexed _oNFT, address indexed _owner, address indexed _operator, bool _approved);

    function licence(address indexed _oNFT, uint256 indexed _oNFT_Id, address indexed _dNFT, uint256 indexed _dNFT_Id, uint64 _expiryTime, LicensingAgreementType _type, string _licenseName, string _licenseUri) external payable; //TODO: mortgages or not?
    
    function approve(address indexed _oNFT, address _approved, uint256 _tokenId) external payable; //TODO: why payable?
    
    function setApprovalForAll(address indexed _oNFT, address _operator, bool _approved) external;
    
    function getApproved(address indexed _oNFT, uint256 _tokenId) external view returns (address);
    
    function isApprovedForAll(address indexed _oNFT, address _owner, address _operator) external view returns (bool);

}

event Licence(
  address indexed _oNFT,
  uint256 indexed _oNFT_Id,
  address indexed _dNFT,
  uint256 indexed _dNFT_Id,
  uint64 _expiryTime,
  LicensingAgreementType _type,
  string _licenseName,
  string _licenseUri
);

event Approval(
  address indexed _oNFT,
  address indexed _owner,
  address indexed _approved,
  uint256 indexed _tokenId
);

event ApprovalForAll(
  address indexed _oNFT,
  address indexed _owner,
  address indexed _operator,
  bool _approved
);

function licence(
  address _oNFT,
  uint256 _oNFT_Id,
  address _dNFT,
  uint256 _dNFT_Id,
  uint64 _expiryTime,
  LicensingAgreementType _type,
  string _licenseName,
  string _licenseUri
) external payable;

function approve(address _oNFT, address _approved, uint256 _tokenId) external payable;

function setApprovalForAll(address _oNFT, address _operator, bool _approved) external;

function getApproved(address _oNFT, uint256 _tokenId) external view returns (address);

function isApprovedForAll(address _oNFT, address _owner, address _operator) external view returns (bool);