InvalidMplexMsgType = object of MuxerError

MessageType {.pure.} = enum
  New, MsgIn, MsgOut, CloseIn, CloseOut, ResetIn, ResetOut

Msg = tuple[id: uint64, msgType: MessageType, data: seq[byte]]

MaxMsgSize = 1048576

proc newInvalidMplexMsgType(): ref InvalidMplexMsgType {....raises: [], tags: [].}

proc readMsg(conn: Connection): InternalRaisesFuture[Msg,
    (CancelledError, LPStreamError, MuxerError)] {.stackTrace: false,
    ...raises: [], gcsafe, raises: [], raises: [], tags: [RootEffect].}

proc writeMsg(conn: Connection; id: uint64; msgType: MessageType;
              data: seq[byte] = @[]): InternalRaisesFuture[void,
    (CancelledError, LPStreamError)] {.stackTrace: false, ...raises: [], gcsafe,
                                       raises: [], raises: [], tags: [].}

proc writeMsg(conn: Connection; id: uint64; msgType: MessageType; data: string): InternalRaisesFuture[
    void, (CancelledError, LPStreamError)] {.stackTrace: false, ...raises: [],
    gcsafe, raises: [], raises: [], tags: [].}