Implement MQTT for Advanced LVA Controls

Adds command-line arguments (--mqtt-host, --mqtt-port, etc., and --num-leds) to configure the MQTT connection and initial LED setup.

Instantiates and starts the MqttController on application startup if an MQTT host is provided.

Includes the MicMuteHandler class, which listens for mute commands, updates the global mic_muted state, and clears the audio queue on unmute to prevent processing stale audio.

Updates the process_audio loop to respect the mic_muted flag.

linux_voice_assistant/__main__.py

@@ -12,8 +12,9 @@ from typing import Dict, List, Optional, Union
 import numpy as np
 import sounddevice as sd
 
-from .event_bus import EventBus
+from .event_bus import EventBus, EventHandler, subscribe
 from .led_controller import LedController
+from .mqtt_controller import MqttController
 from .microwakeword import MicroWakeWord, MicroWakeWordFeatures
 from .models import AvailableWakeWord, Preferences, ServerState, WakeWordType
 from .mpv_player import MpvMediaPlayer
@@ -34,6 +35,34 @@ if is_arm():
 else:
     _LIB_DIR = _REPO_DIR / "lib" / "linux_amd64"
 
+# -----------------------------------------------------------------------------
+
+class MicMuteHandler(EventHandler):
+    """Event handler for mic mute switch."""
+    def __init__(self, state, mqtt_controller: Optional[MqttController]):
+        super().__init__(state)
+        self.mqtt_controller = mqtt_controller
+
+    @subscribe
+    def set_mic_mute(self, data: dict):
+        is_muted = data.get("state", False)
+        if self.state.mic_muted != is_muted:
+            self.state.mic_muted = is_muted
+            _LOGGER.debug("Mic muted = %s", is_muted)
+            
+            if self.mqtt_controller:
+                self.mqtt_controller.publish_mute_state(is_muted)
+            
+            if is_muted:
+                self.state.event_bus.publish("mic_muted")
+            else:
+                _LOGGER.debug("Clearing stale audio queue...")
+                while not self.state.audio_queue.empty():
+                    try:
+                        self.state.audio_queue.get_nowait()
+                    except Queue.Empty:
+                        break
+                self.state.event_bus.publish("mic_unmuted")
 
 # -----------------------------------------------------------------------------
 
@@ -107,6 +136,17 @@ async def main() -> None:
         default=12,
         help="GPIO pin for LED data (for Grove)",
     )
+    # --- ADDED NUM_LEDS ARGUMENT ---
+    parser.add_argument(
+        "--num-leds",
+        type=int,
+        default=3,
+        help="Number of LEDs in the strip",
+    )
+    parser.add_argument("--mqtt-host", help="MQTT broker host")
+    parser.add_argument("--mqtt-port", type=int, default=1883, help="MQTT broker port")
+    parser.add_argument("--mqtt-username", help="MQTT broker username")
+    parser.add_argument("--mqtt-password", help="MQTT broker password")
     parser.add_argument(
         "--debug", action="store_true", help="Print DEBUG messages to console"
     )
@@ -135,7 +175,6 @@ async def main() -> None:
                     trained_languages=model_config.get("trained_languages", []),
                     config_path=model_config_path,
                 )
-
     _LOGGER.debug("Available wake words: %s", list(sorted(available_wake_words.keys())))
     
     preferences_path = Path(args.preferences_file)
@@ -147,9 +186,12 @@ async def main() -> None:
     else:
         preferences = Preferences()
 
+    # Set number of LEDs from command line default, then override with saved preference
+    preferences.num_leds = getattr(preferences, 'num_leds', args.num_leds)
+
+
     libtensorflowlite_c_path = _LIB_DIR / "libtensorflowlite_c.so"
     _LOGGER.debug("libtensorflowlite_c path: %s", libtensorflowlite_c_path)
-
     wake_models: Dict[str, Union[MicroWakeWord, OpenWakeWord]] = {}
     if preferences.active_wake_words:
         for wake_word_id in preferences.active_wake_words:
@@ -164,7 +206,6 @@ async def main() -> None:
         wake_word = available_wake_words[wake_word_id]
         _LOGGER.debug("Loading wake model: %s", wake_word_id)
         wake_models[wake_word_id] = wake_word.load(libtensorflowlite_c_path)
-
     stop_model: Optional[MicroWakeWord] = None
     for wake_word_dir in wake_word_dirs:
         stop_config_path = wake_word_dir / f"{args.stop_model}.json"
@@ -175,9 +216,7 @@ async def main() -> None:
             stop_config_path, libtensorflowlite_c_path
         )
         break
-
     assert stop_model is not None
-
     music_player = MpvMediaPlayer(
         device=args.audio_output_device, initial_volume=preferences.volume_level
     )
@@ -212,8 +251,22 @@ async def main() -> None:
         interface=args.led_interface,
         clock_pin=args.led_clock_pin,
         data_pin=args.led_data_pin,
+        num_leds=state.preferences.num_leds, # Pass number of LEDs
     )
     
+    mqtt_controller: Optional[MqttController] = None
+    if args.mqtt_host:
+        mqtt_controller = MqttController(
+            state=state,
+            host=args.mqtt_host,
+            port=args.mqtt_port,
+            username=args.mqtt_username,
+            password=args.mqtt_password,
+        )
+        mqtt_controller.start()
+    
+    mic_mute_handler = MicMuteHandler(state, mqtt_controller)
+
     process_audio_thread = threading.Thread(
         target=process_audio, args=(state,), daemon=True
     )
@@ -245,6 +298,8 @@ async def main() -> None:
     except KeyboardInterrupt:
         pass
     finally:
+        if mqtt_controller:
+            mqtt_controller.stop()
         state.audio_queue.put_nowait(None)
         process_audio_thread.join()
 
@@ -266,6 +321,10 @@ def process_audio(state: ServerState):
 
     try:
         while True:
+            if state.mic_muted:
+                time.sleep(0.1)
+                continue
+
             audio_chunk = state.audio_queue.get()
             if audio_chunk is None:
                 break