Composable NFTs utilizing Equippable Parts

/// @title EIP-6220 Composable NFTs utilizing Equippable Parts
/// @dev See https://eips.ethereum.org/EIPS/eip-6220
/// @dev Note: the ERC-165 identifier for this interface is 0x28bc9ae4.

pragma solidity ^0.8.16;

import "./IERC5773.sol";

interface IERC6220 is IERC5773 /*, ERC165 */ {
    /**
     * @notice Used to store the core structure of the `Equippable` component.
     * @return assetId The ID of the asset equipping a child
     * @return childAssetId The ID of the asset used as equipment
     * @return childId The ID of token that is equipped
     * @return childEquippableAddress Address of the collection to which the child asset belongs to
     */
    struct Equipment {
        uint64 assetId;
        uint64 childAssetId;
        uint256 childId;
        address childEquippableAddress;
    }

    /**
     * @notice Used to provide a struct for inputing equip data.
     * @dev Only used for input and not storage of data.
     * @return tokenId ID of the token we are managing
     * @return childIndex Index of a child in the list of token's active children
     * @return assetId ID of the asset that we are equipping into
     * @return slotPartId ID of the slot part that we are using to equip
     * @return childAssetId ID of the asset that we are equipping
     */
    struct IntakeEquip {
        uint256 tokenId;
        uint256 childIndex;
        uint64 assetId;
        uint64 slotPartId;
        uint64 childAssetId;
    }

    /**
     * @notice Used to notify listeners that a child's asset has been equipped into one of its parent assets.
     * @param tokenId ID of the token that had an asset equipped
     * @param assetId ID of the asset associated with the token we are equipping into
     * @param slotPartId ID of the slot we are using to equip
     * @param childId ID of the child token we are equipping into the slot
     * @param childAddress Address of the child token's collection
     * @param childAssetId ID of the asset associated with the token we are equipping
     */
    event ChildAssetEquipped(
        uint256 indexed tokenId,
        uint64 indexed assetId,
        uint64 indexed slotPartId,
        uint256 childId,
        address childAddress,
        uint64 childAssetId
    );

    /**
     * @notice Used to notify listeners that a child's asset has been unequipped from one of its parent assets.
     * @param tokenId ID of the token that had an asset unequipped
     * @param assetId ID of the asset associated with the token we are unequipping out of
     * @param slotPartId ID of the slot we are unequipping from
     * @param childId ID of the token being unequipped
     * @param childAddress Address of the collection that a token that is being unequipped belongs to
     * @param childAssetId ID of the asset associated with the token we are unequipping
     */
    event ChildAssetUnequipped(
        uint256 indexed tokenId,
        uint64 indexed assetId,
        uint64 indexed slotPartId,
        uint256 childId,
        address childAddress,
        uint64 childAssetId
    );

    /**
     * @notice Used to notify listeners that the assets belonging to a `equippableGroupId` have been marked as
     *  equippable into a given slot and parent
     * @param equippableGroupId ID of the equippable group being marked as equippable into the slot associated with
     *  `slotPartId` of the `parentAddress` collection
     * @param slotPartId ID of the slot part of the catalog into which the parts belonging to the equippable group
     *  associated with `equippableGroupId` can be equipped
     * @param parentAddress Address of the collection into which the parts belonging to `equippableGroupId` can be
     *  equipped
     */
    event ValidParentEquippableGroupIdSet(
        uint64 indexed equippableGroupId,
        uint64 indexed slotPartId,
        address parentAddress
    );

    /**
     * @notice Used to equip a child into a token.
     * @dev The `IntakeEquip` stuct contains the following data:
     *  [
     *      tokenId,
     *      childIndex,
     *      assetId,
     *      slotPartId,
     *      childAssetId
     *  ]
     * @param data An `IntakeEquip` struct specifying the equip data
     */
    function equip(
        IntakeEquip memory data
    ) external;

    /**
     * @notice Used to unequip child from parent token.
     * @dev This can only be called by the owner of the token or by an account that has been granted permission to
     *  manage the given token by the current owner.
     * @param tokenId ID of the parent from which the child is being unequipped
     * @param assetId ID of the parent's asset that contains the `Slot` into which the child is equipped
     * @param slotPartId ID of the `Slot` from which to unequip the child
     */
    function unequip(
        uint256 tokenId,
        uint64 assetId,
        uint64 slotPartId
    ) external;

    /**
     * @notice Used to check whether the token has a given child equipped.
     * @dev This is used to prevent from transferring a child that is equipped.
     * @param tokenId ID of the parent token for which we are querying for
     * @param childAddress Address of the child token's smart contract
     * @param childId ID of the child token
     * @return bool The boolean value indicating whether the child token is equipped into the given token or not
     */
    function isChildEquipped(
        uint256 tokenId,
        address childAddress,
        uint256 childId
    ) external view returns (bool);

    /**
     * @notice Used to verify whether a token can be equipped into a given parent's slot.
     * @param parent Address of the parent token's smart contract
     * @param tokenId ID of the token we want to equip
     * @param assetId ID of the asset associated with the token we want to equip
     * @param slotId ID of the slot that we want to equip the token into
     * @return bool The boolean indicating whether the token with the given asset can be equipped into the desired
     *  slot
     */
    function canTokenBeEquippedWithAssetIntoSlot(
        address parent,
        uint256 tokenId,
        uint64 assetId,
        uint64 slotId
    ) external view returns (bool);

    /**
     * @notice Used to get the Equipment object equipped into the specified slot of the desired token.
     * @dev The `Equipment` struct consists of the following data:
     *  [
     *      assetId,
     *      childAssetId,
     *      childId,
     *      childEquippableAddress
     *  ]
     * @param tokenId ID of the token for which we are retrieving the equipped object
     * @param targetCatalogAddress Address of the `Catalog` associated with the `Slot` part of the token
     * @param slotPartId ID of the `Slot` part that we are checking for equipped objects
     * @return struct The `Equipment` struct containing data about the equipped object
     */
    function getEquipment(
        uint256 tokenId,
        address targetCatalogAddress,
        uint64 slotPartId
    ) external view returns (Equipment memory);

    /**
     * @notice Used to get the asset and equippable data associated with given `assetId`.
     * @param tokenId ID of the token for which to retrieve the asset
     * @param assetId ID of the asset of which we are retrieving
     * @return metadataURI The metadata URI of the asset
     * @return equippableGroupId ID of the equippable group this asset belongs to
     * @return catalogAddress The address of the catalog the part belongs to
     * @return partIds An array of IDs of parts included in the asset
     */
    function getAssetAndEquippableData(uint256 tokenId, uint64 assetId)
        external
        view
        returns (
            string memory metadataURI,
            uint64 equippableGroupId,
            address catalogAddress,
            uint64[] calldata partIds
        );
}

/**
 * @title ICatalog
 * @notice An interface Catalog for equippable module.
 * @dev Note: the ERC-165 identifier for this interface is 0xd912401f.
 */

pragma solidity ^0.8.16;

interface ICatalog /* is IERC165 */ {
    /**
     * @notice Event to announce addition of a new part.
     * @dev It is emitted when a new part is added.
     * @param partId ID of the part that was added
     * @param itemType Enum value specifying whether the part is `None`, `Slot` and `Fixed`
     * @param zIndex An uint specifying the z value of the part. It is used to specify the depth which the part should
     *  be rendered at
     * @param equippableAddresses An array of addresses that can equip this part
     * @param metadataURI The metadata URI of the part
     */
    event AddedPart(
        uint64 indexed partId,
        ItemType indexed itemType,
        uint8 zIndex,
        address[] equippableAddresses,
        string metadataURI
    );

    /**
     * @notice Event to announce new equippables to the part.
     * @dev It is emitted when new addresses are marked as equippable for `partId`.
     * @param partId ID of the part that had new equippable addresses added
     * @param equippableAddresses An array of the new addresses that can equip this part
     */
    event AddedEquippables(
        uint64 indexed partId,
        address[] equippableAddresses
    );

    /**
     * @notice Event to announce the overriding of equippable addresses of the part.
     * @dev It is emitted when the existing list of addresses marked as equippable for `partId` is overwritten by a new
     *  one.
     * @param partId ID of the part whose list of equippable addresses was overwritten
     * @param equippableAddresses The new, full, list of addresses that can equip this part
     */
    event SetEquippables(uint64 indexed partId, address[] equippableAddresses);

    /**
     * @notice Event to announce that a given part can be equipped by any address.
     * @dev It is emitted when a given part is marked as equippable by any.
     * @param partId ID of the part marked as equippable by any address
     */
    event SetEquippableToAll(uint64 indexed partId);

    /**
     * @notice Used to define a type of the item. Possible values are `None`, `Slot` or `Fixed`.
     * @dev Used for fixed and slot parts.
     */
    enum ItemType {
        None,
        Slot,
        Fixed
    }

    /**
     * @notice The integral structure of a standard RMRK catalog item defining it.
     * @dev Requires a minimum of 3 storage slots per catalog item, equivalent to roughly 60,000 gas as of Berlin hard fork
     *  (April 14, 2021), though 5-7 storage slots is more realistic, given the standard length of an IPFS URI. This
     *  will result in between 25,000,000 and 35,000,000 gas per 250 assets--the maximum block size of Ethereum
     *  mainnet is 30M at peak usage.
     * @return itemType The item type of the part
     * @return z The z value of the part defining how it should be rendered when presenting the full NFT
     * @return equippable The array of addresses allowed to be equipped in this part
     * @return metadataURI The metadata URI of the part
     */
    struct Part {
        ItemType itemType; //1 byte
        uint8 z; //1 byte
        address[] equippable; //n Collections that can be equipped into this slot
        string metadataURI; //n bytes 32+
    }

    /**
     * @notice The structure used to add a new `Part`.
     * @dev The part is added with specified ID, so you have to make sure that you are using an unused `partId`,
     *  otherwise the addition of the part vill be reverted.
     * @dev The full `IntakeStruct` looks like this:
     *  [
     *          partID,
     *      [
     *          itemType,
     *          z,
     *          [
     *               permittedCollectionAddress0,
     *               permittedCollectionAddress1,
     *               permittedCollectionAddress2
     *           ],
     *           metadataURI
     *       ]
     *   ]
     * @return partId ID to be assigned to the `Part`
     * @return part A `Part` to be added
     */
    struct IntakeStruct {
        uint64 partId;
        Part part;
    }

    /**
     * @notice Used to return the metadata URI of the associated catalog.
     * @return string Base metadata URI
     */
    function getMetadataURI() external view returns (string memory);

    /**
     * @notice Used to return the `itemType` of the associated catalog
     * @return string `itemType` of the associated catalog
     */
    function getType() external view returns (string memory);

    /**
     * @notice Used to check whether the given address is allowed to equip the desired `Part`.
     * @dev Returns true if a collection may equip asset with `partId`.
     * @param partId The ID of the part that we are checking
     * @param targetAddress The address that we are checking for whether the part can be equipped into it or not
     * @return bool The status indicating whether the `targetAddress` can be equipped into `Part` with `partId` or not
     */
    function checkIsEquippable(uint64 partId, address targetAddress)
        external
        view
        returns (bool);

    /**
     * @notice Used to check if the part is equippable by all addresses.
     * @dev Returns true if part is equippable to all.
     * @param partId ID of the part that we are checking
     * @return bool The status indicating whether the part with `partId` can be equipped by any address or not
     */
    function checkIsEquippableToAll(uint64 partId) external view returns (bool);

    /**
     * @notice Used to retrieve a `Part` with id `partId`
     * @param partId ID of the part that we are retrieving
     * @return struct The `Part` struct associated with given `partId`
     */
    function getPart(uint64 partId) external view returns (Part memory);

    /**
     * @notice Used to retrieve multiple parts at the same time.
     * @param partIds An array of part IDs that we want to retrieve
     * @return struct An array of `Part` structs associated with given `partIds`
     */
    function getParts(uint64[] calldata partIds)
        external
        view
        returns (Part[] memory);
}