feat: Add MQTT commands for music playback control

Co-authored-by: aider (gemini/gemini-2.5-pro) <aider@aider.chat>

main.py

@@ -25,6 +25,7 @@ pairing_task = None
 BLUEZ_SERVICE = 'org.bluez'
 ADAPTER_IFACE = 'org.bluez.Adapter1'
 DEVICE_IFACE = 'org.bluez.Device1'
+MEDIA_PLAYER_IFACE = 'org.bluez.MediaPlayer1'
 AGENT_IFACE = 'org.bluez.Agent1'
 AGENT_MANAGER_IFACE = 'org.bluez.AgentManager1'
 AGENT_PATH = '/io/bluetooth_speaker/agent'
@@ -205,6 +206,34 @@ async def disconnect_connected_device():
     logging.info("No connected device found to disconnect.")
 
 
+async def send_media_command(command):
+    """Finds a media player and sends a command to it."""
+    logging.info(f"Attempting to send media command: {command}")
+    introspection = await bus.introspect(BLUEZ_SERVICE, '/')
+    manager_obj = bus.get_proxy_object(BLUEZ_SERVICE, '/', introspection)
+    manager_iface = manager_obj.get_interface('org.freedesktop.DBus.ObjectManager')
+    managed_objects = await manager_iface.call_get_managed_objects()
+
+    for path, ifaces in managed_objects.items():
+        if MEDIA_PLAYER_IFACE in ifaces:
+            logging.info(f"Found media player: {path}. Sending command '{command}'...")
+            try:
+                player_introspection = await bus.introspect(BLUEZ_SERVICE, path)
+                player_obj = bus.get_proxy_object(BLUEZ_SERVICE, path, player_introspection)
+                player_iface = player_obj.get_interface(MEDIA_PLAYER_IFACE)
+
+                method_name = f'call_{command}'
+                dbus_method = getattr(player_iface, method_name)
+                await dbus_method()
+
+                logging.info(f"Successfully sent command '{command}' to {path}")
+                return # Assume only one media player is active
+            except Exception as e:
+                logging.error(f"Failed to send media command to {path}: {e}")
+
+    logging.warning("No active media player found to send command to.")
+
+
 async def process_bluetooth_command(topic, text):
     global pairing_task
     logging.info('Bluetooth command: %s', text)
@@ -215,6 +244,9 @@ async def process_bluetooth_command(topic, text):
         pairing_task = asyncio.create_task(enable_pairing())
     elif text == "kick":
         await disconnect_connected_device()
+    elif text in ["play", "pause", "next", "prev"]:
+        command = "previous" if text == "prev" else text
+        await send_media_command(command)
 
 async def process_mqtt(message):
     text = message.payload.decode()