from queue import Queue import frame_handler from event_manager import EventManager from state_manager import StateManager from modem_frametypes import FRAME_TYPE as FR from arq_session_irs import ARQSessionIRS from arq_session_iss import ARQSessionISS from arq_session_irs import IRS_State class ARQFrameHandler(frame_handler.FrameHandler): """Handles ARQ frames and manages ARQ sessions. This class processes incoming ARQ frames, manages ARQ sessions for both ISS (Information Sending Station) and IRS (Information Receiving Station), and dispatches frames to the appropriate session based on their type and session ID. """ def follow_protocol(self): """Processes the received ARQ frame based on its type. This method handles different ARQ frame types, including session open, information, burst data, stop, and various acknowledgements. It manages session creation, retrieval, and updates based on the frame type and session ID. """ if not self.should_respond(): return frame = self.details['frame'] session_id = frame['session_id'] snr = self.details["snr"] frequency_offset = self.details["frequency_offset"] if frame['frame_type_int'] == FR.ARQ_SESSION_OPEN.value: print("Received ARQ_SESSION_OPEN frame") print(f"Session ID: {session_id}") # Handle cases where the session_id is already present in arq_irs_sessions if session_id in self.states.arq_irs_sessions: print(f"ARQ session already in memory: {session_id}") session = self.states.arq_irs_sessions[session_id] current_state = session.state print(f"ARQ session state: {current_state}") # Lost OPEN_ACK case .. ISS will retry opening a session if current_state in [IRS_State.NEW, IRS_State.OPEN_ACK_SENT]: print("Lost OPEN_ACK case: ISS will retry opening a session.") # Case where a transmission has failed, we want to continue the transmission elif current_state in [IRS_State.FAILED, IRS_State.ABORTED]: print("Transmission failed: Will continue the transmission.") # TODO Lets consider adding an additional state here session.state = IRS_State.NEW # Case where we just want to retransmit an already transmitted message elif current_state == IRS_State.ENDED: print("Retransmitting an already transmitted message.") session.reset_session() session.state = IRS_State.NEW # Normal case when receiving a SESSION_OPEN for the first time else: print("First-time reception of SESSION_OPEN frame.") if self.states.check_if_running_arq_session(): self.logger.warning("DISCARDING SESSION OPEN because of ongoing ARQ session ", frame=frame) return session = ARQSessionIRS(self.config, self.modem, frame['origin'], session_id, self.states) self.states.register_arq_irs_session(session) elif frame['frame_type_int'] in [ FR.ARQ_SESSION_INFO.value, FR.ARQ_BURST_FRAME.value, FR.ARQ_STOP.value, ]: print("Received ARQ frame of type: INFO, BURST, or STOP.") session = self.states.get_arq_irs_session(session_id) elif frame['frame_type_int'] in [ FR.ARQ_SESSION_OPEN_ACK.value, FR.ARQ_SESSION_INFO_ACK.value, FR.ARQ_BURST_ACK.value, FR.ARQ_STOP_ACK.value ]: print("Received ARQ ACK frame of type: OPEN_ACK, INFO_ACK, BURST_ACK, or STOP_ACK.") session = self.states.get_arq_iss_session(session_id) else: self.logger.warning("DISCARDING FRAME", frame=frame) return session.set_details(snr, frequency_offset) session.on_frame_received(frame)