Implement receive queue and UI shutdown handling in app state

contact/__main__.py

@@ -15,6 +15,7 @@ import curses
 import io
 import logging
 import os
+import queue
 import subprocess
 import sys
 import threading
@@ -54,6 +55,8 @@ logging.basicConfig(
 )
 
 app_state.lock = threading.Lock()
+app_state.rx_queue = queue.SimpleQueue()
+app_state.ui_shutdown = False
 
 
 # ------------------------------------------------------------------------------
@@ -149,11 +152,10 @@ def start() -> None:
         sys.exit(0)
 
     try:
+        app_state.ui_shutdown = False
         curses.wrapper(main)
-        interface_state.interface.close()
     except KeyboardInterrupt:
         logging.info("User exited with Ctrl+C")
-        interface_state.interface.close()
         sys.exit(0)
     except Exception as e:
         logging.critical("Fatal error", exc_info=True)
@@ -164,6 +166,13 @@ def start() -> None:
         print("Fatal error:", e)
         traceback.print_exc()
         sys.exit(1)
+    finally:
+        app_state.ui_shutdown = True
+        try:
+            if interface_state.interface is not None:
+                interface_state.interface.close()
+        except Exception:
+            logging.exception("Error while closing interface")
 
 
 if __name__ == "__main__":

contact/message_handlers/rx_handler.py

@@ -2,10 +2,22 @@ import logging
 import os
 import platform
 import shutil
-import time
 import subprocess
 import threading
- # Debounce notification sounds so a burst of queued messages only plays once.
+import time
+from typing import Any, Dict
+
+import contact.ui.default_config as config
+from contact.utilities.db_handler import (
+    get_name_from_database,
+    maybe_store_nodeinfo_in_db,
+    save_message_to_db,
+    update_node_info_in_db,
+)
+from contact.utilities.singleton import app_state, interface_state, menu_state, ui_state
+from contact.utilities.utils import add_new_message, refresh_node_list
+
+# Debounce notification sounds so a burst of queued messages only plays once.
 _SOUND_DEBOUNCE_SECONDS = 0.8
 _sound_timer: threading.Timer | None = None
 _sound_timer_lock = threading.Lock()
@@ -13,18 +25,13 @@ _last_sound_request = 0.0
 
 
 def schedule_notification_sound(delay: float = _SOUND_DEBOUNCE_SECONDS) -> None:
-    """Schedule a notification sound after a short quiet period.
+    """Schedule a notification sound after a short quiet period."""
-
-    If more messages arrive before the delay elapses, the timer is reset.
-    This prevents playing a sound for each message when a backlog flushes.
-    """
     global _sound_timer, _last_sound_request
 
     now = time.monotonic()
     with _sound_timer_lock:
         _last_sound_request = now
 
-        # Cancel any previously scheduled sound.
         if _sound_timer is not None:
             try:
                 _sound_timer.cancel()
@@ -33,7 +40,6 @@ def schedule_notification_sound(delay: float = _SOUND_DEBOUNCE_SECONDS) -> None:
             _sound_timer = None
 
         def _fire(expected_request_time: float) -> None:
-            # Only play if nothing newer has been scheduled.
             with _sound_timer_lock:
                 if expected_request_time != _last_sound_request:
                     return
@@ -42,44 +48,20 @@ def schedule_notification_sound(delay: float = _SOUND_DEBOUNCE_SECONDS) -> None:
         _sound_timer = threading.Timer(delay, _fire, args=(now,))
         _sound_timer.daemon = True
         _sound_timer.start()
-from typing import Any, Dict
-
-from contact.utilities.utils import (
-    refresh_node_list,
-    add_new_message,
-)
-from contact.ui.contact_ui import (
-    draw_packetlog_win,
-    draw_node_list,
-    draw_messages_window,
-    draw_channel_list,
-    add_notification,
-)
-from contact.utilities.db_handler import (
-    save_message_to_db,
-    maybe_store_nodeinfo_in_db,
-    get_name_from_database,
-    update_node_info_in_db,
-)
-import contact.ui.default_config as config
-
-from contact.utilities.singleton import ui_state, interface_state, app_state, menu_state
 
 
-def play_sound():
+def play_sound() -> None:
     try:
         system = platform.system()
         sound_path = None
         executable = None
 
-        if system == "Darwin":  # macOS
+        if system == "Darwin":
             sound_path = "/System/Library/Sounds/Ping.aiff"
             executable = "afplay"
-
         elif system == "Linux":
             ogg_path = "/usr/share/sounds/freedesktop/stereo/complete.oga"
-            wav_path = "/usr/share/sounds/alsa/Front_Center.wav"  # common fallback
+            wav_path = "/usr/share/sounds/alsa/Front_Center.wav"
-
             if shutil.which("paplay") and os.path.exists(ogg_path):
                 executable = "paplay"
                 sound_path = ogg_path
@@ -96,102 +78,127 @@ def play_sound():
             cmd = [executable, sound_path]
             if executable == "ffplay":
                 cmd = [executable, "-nodisp", "-autoexit", sound_path]
-
             subprocess.run(cmd, check=True, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
-            return
+    except subprocess.CalledProcessError as exc:
+        logging.error("Sound playback failed: %s", exc)
+    except Exception as exc:
+        logging.error("Unexpected error while playing sound: %s", exc)
 
-    except subprocess.CalledProcessError as e:
+
-        logging.error(f"Sound playback failed: {e}")
+def _decode_message_payload(payload: Any) -> str:
-    except Exception as e:
+    if isinstance(payload, bytes):
-        logging.error(f"Unexpected error: {e}")
+        return payload.decode("utf-8", errors="replace")
+    if isinstance(payload, str):
+        return payload
+    return str(payload)
+
+
+def process_receive_event(packet: Dict[str, Any]) -> None:
+    """Process a queued packet on the UI thread and perform all UI updates."""
+    # Local import prevents module-level circular import.
+    from contact.ui.contact_ui import (
+        add_notification,
+        draw_channel_list,
+        draw_messages_window,
+        draw_node_list,
+        draw_packetlog_win,
+    )
+
+    # Update packet log
+    ui_state.packet_buffer.append(packet)
+    if len(ui_state.packet_buffer) > 20:
+        ui_state.packet_buffer = ui_state.packet_buffer[-20:]
+
+    if ui_state.display_log:
+        draw_packetlog_win()
+        if ui_state.current_window == 4:
+            menu_state.need_redraw = True
+
+    decoded = packet.get("decoded")
+    if not isinstance(decoded, dict):
+        return
+
+    changed = refresh_node_list()
+    if changed:
+        draw_node_list()
+
+    portnum = decoded.get("portnum")
+    if portnum == "NODEINFO_APP":
+        user = decoded.get("user")
+        if isinstance(user, dict) and "longName" in user:
+            maybe_store_nodeinfo_in_db(packet)
+        return
+
+    if portnum != "TEXT_MESSAGE_APP":
+        return
+
+    hop_start = packet.get("hopStart", 0)
+    hop_limit = packet.get("hopLimit", 0)
+    hops = hop_start - hop_limit
+
+    if config.notification_sound == "True":
+        schedule_notification_sound()
+
+    message_string = _decode_message_payload(decoded.get("payload"))
+
+    if not ui_state.channel_list:
+        return
+
+    refresh_channels = False
+    refresh_messages = False
+
+    channel_number = packet.get("channel", 0)
+    if not isinstance(channel_number, int):
+        channel_number = 0
+    if channel_number < 0:
+        channel_number = 0
+
+    packet_from = packet.get("from")
+    if packet.get("to") == interface_state.myNodeNum and packet_from is not None:
+        if packet_from not in ui_state.channel_list:
+            ui_state.channel_list.append(packet_from)
+            if packet_from not in ui_state.all_messages:
+                ui_state.all_messages[packet_from] = []
+            update_node_info_in_db(packet_from, chat_archived=False)
+            refresh_channels = True
+        channel_number = ui_state.channel_list.index(packet_from)
+
+    if channel_number >= len(ui_state.channel_list):
+        channel_number = 0
+
+    channel_id = ui_state.channel_list[channel_number]
+
+    if ui_state.selected_channel >= len(ui_state.channel_list):
+        ui_state.selected_channel = 0
+
+    if channel_id != ui_state.channel_list[ui_state.selected_channel]:
+        add_notification(channel_number)
+        refresh_channels = True
+    else:
+        refresh_messages = True
+
+    if packet_from is None:
+        logging.debug("Skipping TEXT_MESSAGE_APP packet with missing 'from' field")
+        return
+
+    message_from_string = get_name_from_database(packet_from, type="short") + ":"
+    add_new_message(channel_id, f"{config.message_prefix} [{hops}] {message_from_string} ", message_string)
+
+    if refresh_channels:
+        draw_channel_list()
+    if refresh_messages:
+        draw_messages_window(True)
+
+    save_message_to_db(channel_id, packet_from, message_string)
 
 
 def on_receive(packet: Dict[str, Any], interface: Any) -> None:
-    """
+    """Enqueue packet to be processed on the main curses thread."""
-    Handles an incoming packet from a Meshtastic interface.
+    if app_state.ui_shutdown:
-
+        return
-    Args:
+    if not isinstance(packet, dict):
-        packet: The received Meshtastic packet as a dictionary.
+        return
-        interface: The Meshtastic interface instance that received the packet.
+    try:
-    """
+        app_state.rx_queue.put(packet)
-    with app_state.lock:
+    except Exception:
-        # Update packet log
+        logging.exception("Failed to enqueue packet for UI processing")
-        ui_state.packet_buffer.append(packet)
-        if len(ui_state.packet_buffer) > 20:
-            # Trim buffer to 20 packets
-            ui_state.packet_buffer = ui_state.packet_buffer[-20:]
-
-        if ui_state.display_log:
-            draw_packetlog_win()
-
-            if ui_state.current_window == 4:
-                menu_state.need_redraw = True
-        try:
-            if "decoded" not in packet:
-                return
-
-            # Assume any incoming packet could update the last seen time for a node
-            changed = refresh_node_list()
-            if changed:
-                draw_node_list()
-
-            if packet["decoded"]["portnum"] == "NODEINFO_APP":
-                if "user" in packet["decoded"] and "longName" in packet["decoded"]["user"]:
-                    maybe_store_nodeinfo_in_db(packet)
-
-            elif packet["decoded"]["portnum"] == "TEXT_MESSAGE_APP":
-                hop_start = packet.get('hopStart', 0)
-                hop_limit = packet.get('hopLimit', 0)
-
-                hops = hop_start - hop_limit
-
-
-                if config.notification_sound == "True":
-                    schedule_notification_sound()
-
-                message_bytes = packet["decoded"]["payload"]
-                message_string = message_bytes.decode("utf-8")
-
-                refresh_channels = False
-                refresh_messages = False
-
-                if packet.get("channel"):
-                    channel_number = packet["channel"]
-                else:
-                    channel_number = 0
-
-                if packet["to"] == interface_state.myNodeNum:
-                    if packet["from"] in ui_state.channel_list:
-                        pass
-                    else:
-                        ui_state.channel_list.append(packet["from"])
-                        if packet["from"] not in ui_state.all_messages:
-                            ui_state.all_messages[packet["from"]] = []
-                        update_node_info_in_db(packet["from"], chat_archived=False)
-                        refresh_channels = True
-
-                    channel_number = ui_state.channel_list.index(packet["from"])
-
-                channel_id = ui_state.channel_list[channel_number]
-
-                if channel_id != ui_state.channel_list[ui_state.selected_channel]:
-                    add_notification(channel_number)
-                    refresh_channels = True
-                else:
-                    refresh_messages = True
-
-                # Add received message to the messages list
-                message_from_id = packet["from"]
-                message_from_string = get_name_from_database(message_from_id, type="short") + ":"
-
-                add_new_message(channel_id, f"{config.message_prefix} [{hops}] {message_from_string} ", message_string)
-
-                if refresh_channels:
-                    draw_channel_list()
-                if refresh_messages:
-                    draw_messages_window(True)
-
-                save_message_to_db(channel_id, message_from_id, message_string)
-
-        except KeyError as e:
-            logging.error(f"Error processing packet: {e}")

contact/ui/contact_ui.py

@@ -1,9 +1,11 @@
 import curses
 import logging
+from queue import Empty
 import time
 import traceback
 from typing import Union
 
+from contact.message_handlers.rx_handler import process_receive_event
 from contact.utilities.utils import get_channels, get_readable_duration, get_time_ago, refresh_node_list
 from contact.settings import settings_menu
 from contact.message_handlers.tx_handler import send_message, send_traceroute
@@ -15,7 +17,7 @@ from contact.utilities.i18n import t
 import contact.ui.default_config as config
 import contact.ui.dialog
 from contact.ui.nav_utils import move_main_highlight, draw_main_arrows, get_msg_window_lines, wrap_text
-from contact.utilities.singleton import ui_state, interface_state, menu_state
+from contact.utilities.singleton import ui_state, interface_state, menu_state, app_state
 
 
 MIN_COL = 1  # "effectively zero" without breaking curses
@@ -161,6 +163,24 @@ def handle_resize(stdscr: curses.window, firstrun: bool) -> None:
         pass
 
 
+def drain_receive_queue(max_events: int = 200) -> None:
+    processed = 0
+    while processed < max_events:
+        try:
+            packet = app_state.rx_queue.get(block=False)
+        except Empty:
+            return
+        except Exception:
+            logging.exception("Error while draining receive queue")
+            return
+
+        try:
+            process_receive_event(packet)
+        except Exception:
+            logging.exception("Error while processing receive event")
+        processed += 1
+
+
 def main_ui(stdscr: curses.window) -> None:
     """Main UI loop for the curses interface."""
     global input_text
@@ -171,12 +191,17 @@ def main_ui(stdscr: curses.window) -> None:
     stdscr.keypad(True)
     get_channels()
     handle_resize(stdscr, True)
+    entry_win.timeout(75)
 
     while True:
+        drain_receive_queue()
         draw_text_field(entry_win, f"Message: {(input_text or '')[-(stdscr.getmaxyx()[1] - 10):]}", get_color("input"))
 
         # Get user input from entry window
-        char = entry_win.get_wch()
+        try:
+            char = entry_win.get_wch()
+        except curses.error:
+            continue
 
         # draw_debug(f"Keypress: {char}")
 
@@ -225,6 +250,7 @@ def main_ui(stdscr: curses.window) -> None:
         elif char == curses.KEY_RESIZE:
             input_text = ""
             handle_resize(stdscr, False)
+            entry_win.timeout(75)
 
         elif char == chr(4):  # Ctrl + D to delete current channel or node
             handle_ctrl_d()

contact/ui/ui_state.py

@@ -1,3 +1,4 @@
+from queue import SimpleQueue
 from typing import Any, Union, List, Dict
 from dataclasses import dataclass, field
 
@@ -44,3 +45,5 @@ class InterfaceState:
 @dataclass
 class AppState:
     lock: Any = None
+    rx_queue: SimpleQueue = field(default_factory=SimpleQueue)
+    ui_shutdown: bool = False