Update __main__.py

Extended Preferences loading to initialize and backfill a new alarm_duration_seconds field (default 0).

Added a set_alarm_duration event handler to MicMuteHandler which:

validates and normalizes the duration value,

updates state.preferences.alarm_duration_seconds,

persists the updated preferences to disk.

Kept the existing “single writer” pattern (MicMuteHandler) for preferences/state updates.

linux_voice_assistant/__main__.py

@@ -48,7 +48,7 @@ class MediaPlayers:
     tts: MpvMediaPlayer
 
 # -----------------------------------------------------------------------------
-# Mic Mute Handler
+# Mic Mute / Preferences Handler
 # -----------------------------------------------------------------------------
 
 class MicMuteHandler(EventHandler):
@@ -98,6 +98,45 @@ class MicMuteHandler(EventHandler):
             self.state.preferences.num_leds = num_leds
             self.state.save_preferences()
 
+    @subscribe
+    def set_alarm_duration(self, data: dict):
+        """
+        Event handler to save alarm_duration_seconds to preferences.
+
+        Expected payload from MQTT controller:
+            { "alarm_duration_seconds": <int> }
+
+        Semantics:
+            0  -> infinite alarm (only stop via Stop wake word / wake word logic)
+            >0 -> auto-stop alarm after N seconds (plus Stop wake word support)
+        """
+        duration = data.get("alarm_duration_seconds")
+        if duration is None:
+            return
+
+        try:
+            duration = int(duration)
+        except (TypeError, ValueError):
+            _LOGGER.warning(
+                "Invalid alarm_duration_seconds value received: %r", duration
+            )
+            return
+
+        if duration < 0:
+            _LOGGER.warning(
+                "Negative alarm_duration_seconds (%d) is not allowed; ignoring",
+                duration,
+            )
+            return
+
+        current = getattr(self.state.preferences, "alarm_duration_seconds", 0)
+        if current != duration:
+            _LOGGER.debug(
+                "Updating alarm_duration_seconds: %s -> %s", current, duration
+            )
+            self.state.preferences.alarm_duration_seconds = duration
+            self.state.save_preferences()
+
 # -----------------------------------------------------------------------------
 # Main Application
 # -----------------------------------------------------------------------------
@@ -166,7 +205,10 @@ def _init_basics() -> Tuple[Config, asyncio.AbstractEventLoop, EventBus]:
             for idx, mic in enumerate(sc.all_microphones(include_loopback=False)):
                 print(f"[{idx}]", mic.name)
         except Exception as e:
-            _LOGGER.error("Error listing input devices (ensure audio backend is working): %s", e)
+            _LOGGER.error(
+                "Error listing input devices (ensure audio backend is working): %s",
+                e,
+            )
         sys.exit(0)
 
     if args.list_output_devices:
@@ -210,7 +252,13 @@ def _load_preferences(config: Config) -> Preferences:
     else:
         preferences = Preferences()
 
-    preferences.num_leds = getattr(preferences, 'num_leds', config.led.num_leds)
+    # Backwards-compatible defaults / migrations
+    preferences.num_leds = getattr(preferences, "num_leds", config.led.num_leds)
+    # New: default alarm_duration_seconds, 0 = infinite until Stop/wake word
+    preferences.alarm_duration_seconds = getattr(
+        preferences, "alarm_duration_seconds", 0
+    )
+
     return preferences
 
 def _get_microphone(config: Config):
@@ -294,17 +342,21 @@ def _load_wake_words(config: Config, preferences: Preferences) -> WakeWordData:
 
     return WakeWordData(available, models, active, stop_model)
 
-def _init_media_players(loop: asyncio.AbstractEventLoop, config: Config, preferences: Preferences) -> MediaPlayers:
+def _init_media_players(
+    loop: asyncio.AbstractEventLoop,
+    config: Config,
+    preferences: Preferences,
+) -> MediaPlayers:
     """Initializes the music and TTS media players."""
     music_player = MpvMediaPlayer(
         loop=loop,
         device=config.audio.output_device,
-        initial_volume=preferences.volume_level
+        initial_volume=preferences.volume_level,
     )
     tts_player = MpvMediaPlayer(
         loop=loop,
         device=config.audio.output_device,
-        initial_volume=preferences.volume_level
+        initial_volume=preferences.volume_level,
     )
     return MediaPlayers(music=music_player, tts=tts_player)
 
@@ -377,13 +429,15 @@ async def _run_server(state: ServerState, config: Config):
     server = await state.loop.create_server(
         lambda: VoiceSatelliteProtocol(state),
         host=config.esphome.host,
-        port=config.esphome.port
+        port=config.esphome.port,
     )
     discovery = HomeAssistantZeroconf(port=config.esphome.port, name=config.app.name)
     await discovery.register_server()
 
     async with server:
-        _LOGGER.info("Server started (host=%s, port=%s)", config.esphome.host, config.esphome.port)
+        _LOGGER.info(
+            "Server started (host=%s, port=%s)", config.esphome.host, config.esphome.port
+        )
         await server.serve_forever()