ISocket.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.13;

/**
 * @title ISocket
 * @notice An interface for a cross-chain communication contract
 * @dev This interface provides methods for transmitting and executing messages between chains,
 * connecting a plug to a remote chain and setting up switchboards for the message transmission
 * This interface also emits events for important operations such as message transmission, execution status,
 * and plug connection
 */
interface ISocket {
    /**
     * @notice A struct containing fees required for message transmission and execution
     * @param transmissionFees fees needed for transmission
     * @param switchboardFees fees needed by switchboard
     * @param executionFee fees needed for execution
     */
    struct Fees {
        uint128 transmissionFees;
        uint128 executionFee;
        uint128 switchboardFees;
    }

    /**
     * @title MessageDetails
     * @dev This struct defines the details of a message to be executed in a Decapacitor contract.
     */
    struct MessageDetails {
        // A unique identifier for the message.
        bytes32 msgId;
        // The fee to be paid for executing the message.
        uint256 executionFee;
        // The maximum amount of gas that can be used to execute the message.
        uint256 minMsgGasLimit;
        // The extra params which provides msg value and additional info needed for message exec
        bytes32 executionParams;
        // The payload data to be executed in the message.
        bytes payload;
    }

    /**
     * @title ExecutionDetails
     * @dev This struct defines the execution details
     */
    struct ExecutionDetails {
        // packet id
        bytes32 packetId;
        // proposal count
        uint256 proposalCount;
        // gas limit needed to execute inbound
        uint256 executionGasLimit;
        // proof data required by the Decapacitor contract to verify the message's authenticity
        bytes decapacitorProof;
        // signature of executor
        bytes signature;
    }

    /**
     * @notice emits the message details when a new message arrives at outbound
     * @param localChainSlug local chain slug
     * @param localPlug local plug address
     * @param dstChainSlug remote chain slug
     * @param dstPlug remote plug address
     * @param msgId message id packed with remoteChainSlug and nonce
     * @param minMsgGasLimit gas limit needed to execute the inbound at remote
     * @param payload the data which will be used by inbound at remote
     */
    event MessageOutbound(
        uint32 localChainSlug,
        address localPlug,
        uint32 dstChainSlug,
        address dstPlug,
        bytes32 msgId,
        uint256 minMsgGasLimit,
        bytes32 executionParams,
        bytes32 transmissionParams,
        bytes payload,
        Fees fees
    );

    /**
     * @notice emits the status of message after inbound call
     * @param msgId msg id which is executed
     */
    event ExecutionSuccess(bytes32 msgId);

    /**
     * @notice emits the config set by a plug for a remoteChainSlug
     * @param plug address of plug on current chain
     * @param siblingChainSlug sibling chain slug
     * @param siblingPlug address of plug on sibling chain
     * @param inboundSwitchboard inbound switchboard (select from registered options)
     * @param outboundSwitchboard outbound switchboard (select from registered options)
     * @param capacitor capacitor selected based on outbound switchboard
     * @param decapacitor decapacitor selected based on inbound switchboard
     */
    event PlugConnected(
        address plug,
        uint32 siblingChainSlug,
        address siblingPlug,
        address inboundSwitchboard,
        address outboundSwitchboard,
        address capacitor,
        address decapacitor
    );

    /**
     * @notice registers a message
     * @dev Packs the message and includes it in a packet with capacitor
     * @param remoteChainSlug_ the remote chain slug
     * @param minMsgGasLimit_ the gas limit needed to execute the payload on remote
     * @param payload_ the data which is needed by plug at inbound call on remote
     */
    function outbound(
        uint32 remoteChainSlug_,
        uint256 minMsgGasLimit_,
        bytes32 executionParams_,
        bytes32 transmissionParams_,
        bytes memory payload_
    ) external payable returns (bytes32 msgId);

    /**
     * @notice executes a message
     * @param executionDetails_ the packet details, proof and signature needed for message execution
     * @param messageDetails_ the message details
     */
    function execute(
        ISocket.ExecutionDetails calldata executionDetails_,
        ISocket.MessageDetails calldata messageDetails_
    ) external payable;

    /**
     * @notice sets the config specific to the plug
     * @param siblingChainSlug_ the sibling chain slug
     * @param siblingPlug_ address of plug present at sibling chain to call inbound
     * @param inboundSwitchboard_ the address of switchboard to use for receiving messages
     * @param outboundSwitchboard_ the address of switchboard to use for sending messages
     */
    function connect(
        uint32 siblingChainSlug_,
        address siblingPlug_,
        address inboundSwitchboard_,
        address outboundSwitchboard_
    ) external;

    /**
     * @notice Retrieves the minimum fees required for a message with a specified gas limit and destination chain.
     * @param minMsgGasLimit_ The gas limit of the message.
     * @param remoteChainSlug_ The slug of the destination chain for the message.
     * @param plug_ The address of the plug through which the message is sent.
     * @return totalFees The minimum fees required for the specified message.
     */
    function getMinFees(
        uint256 minMsgGasLimit_,
        uint256 payloadSize_,
        bytes32 executionParams_,
        bytes32 transmissionParams_,
        uint32 remoteChainSlug_,
        address plug_
    ) external view returns (uint256 totalFees);

    /**
     * @notice returns chain slug
     * @return chainSlug current chain slug
     */
    function chainSlug() external view returns (uint32 chainSlug);

    function globalMessageCount() external view returns (uint64);

    /**
     * @notice returns the config for given `plugAddress_` and `siblingChainSlug_`
     * @param siblingChainSlug_ the sibling chain slug
     * @param plugAddress_ address of plug present at current chain
     */
    function getPlugConfig(
        address plugAddress_,
        uint32 siblingChainSlug_
    )
        external
        view
        returns (
            address siblingPlug,
            address inboundSwitchboard__,
            address outboundSwitchboard__,
            address capacitor__,
            address decapacitor__
        );
}