Bluetooth mic routing fix

AudioRecorder.kt

@@ -0,0 +1,20 @@
+// Other existing imports
+import android.media.AudioManager;
+import android.telecom.Call;
+import android.bluetooth.BluetoothAdapter;
+import android.bluetooth.BluetoothDevice;
+
+// Function to detect connected Bluetooth devices
+private AudioDevice getAudioSource() {
+    BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
+    if (bluetoothAdapter != null && bluetoothAdapter.isEnabled()) {
+        for (BluetoothDevice device : bluetoothAdapter.getBondedDevices()) {
+            if (device.getType() == BluetoothDevice.DEVICE_TYPE_AUDIO) {
+                // return audio source associated with the Bluetooth device
+                return AudioDevice.BLUETOOTH;
+            }
+        }
+    }
+    // Fallback to default audio source if no Bluetooth devices are connected
+    return AudioDevice.DEFAULT;
+}

common/src/main/kotlin/io/homeassistant/companion/android/common/util/AudioRecorder.kt

@@ -1,6 +1,7 @@
 package io.homeassistant.companion.android.common.util
 
 import android.annotation.SuppressLint
+import android.media.AudioDeviceInfo
 import android.media.AudioFormat
 import android.media.AudioManager
 import android.media.AudioManager.OnAudioFocusChangeListener
@@ -17,6 +18,7 @@ import kotlinx.coroutines.flow.MutableSharedFlow
 import kotlinx.coroutines.flow.asSharedFlow
 import kotlinx.coroutines.isActive
 import kotlinx.coroutines.launch
+import android.os.Build
 
 /**
  * Wrapper around [AudioRecord] providing pre-configured audio recording functionality.
@@ -30,7 +32,6 @@ class AudioRecorder(private val audioManager: AudioManager?) {
         // Docs: only format '[g]uaranteed to be supported by devices'
         private const val AUDIO_FORMAT = AudioFormat.ENCODING_PCM_16BIT
 
-        private const val AUDIO_SOURCE = AudioSource.MIC
         private const val CHANNEL_CONFIG = AudioFormat.CHANNEL_IN_MONO
     }
 
@@ -50,6 +51,25 @@ class AudioRecorder(private val audioManager: AudioManager?) {
     private var focusRequest: AudioFocusRequestCompat? = null
     private val focusListener = OnAudioFocusChangeListener { /* Not used */ }
 
+    /**
+     * Determine the appropriate audio source based on connected devices.
+     * Prefers Bluetooth SCO if available, falls back to VOICE_COMMUNICATION,
+     * and finally defaults to MIC if neither is available.
+     */
+    private fun getAudioSource(): Int {
+        if (audioManager == null) {
+            return AudioSource.MIC
+        }
+
+        // Check if Bluetooth SCO is available
+        return if (audioManager.isBluetoothScoAvailableOffCall()) {
+            // Use VOICE_COMMUNICATION which is the standard for Bluetooth audio
+            AudioSource.VOICE_COMMUNICATION
+        } else {
+            AudioSource.MIC
+        }
+    }
+
     /**
      * Start the recorder. After calling this function, data will be available via [audioBytes].
      * @throws SecurityException when missing permission to record audio
@@ -101,8 +121,9 @@ class AudioRecorder(private val audioManager: AudioManager?) {
     private fun setupRecorder() {
         if (recorder != null) stopRecording()
 
+        val audioSource = getAudioSource()
         val bufferSize = minBufferSize() * 10
-        recorder = AudioRecord(AUDIO_SOURCE, SAMPLE_RATE, CHANNEL_CONFIG, AUDIO_FORMAT, bufferSize)
+        recorder = AudioRecord(audioSource, SAMPLE_RATE, CHANNEL_CONFIG, AUDIO_FORMAT, bufferSize)
     }
 
     private fun releaseRecorder() {
@@ -114,6 +135,14 @@ class AudioRecorder(private val audioManager: AudioManager?) {
 
     private fun requestFocus() {
         if (audioManager == null) return
+
+        // Enable Bluetooth SCO if available (requires API 11+)
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
+            if (audioManager.isBluetoothScoAvailableOffCall()) {
+                audioManager.startBluetoothSco()
+            }
+        }
+
         if (focusRequest == null) {
             focusRequest = AudioFocusRequestCompat.Builder(AudioManagerCompat.AUDIOFOCUS_GAIN_TRANSIENT_EXCLUSIVE).run {
                 setAudioAttributes(
@@ -138,7 +167,15 @@ class AudioRecorder(private val audioManager: AudioManager?) {
     }
 
     private fun abandonFocus() {
-        if (audioManager == null || focusRequest == null) return
-        AudioManagerCompat.abandonAudioFocusRequest(audioManager, focusRequest!!)
+        if (audioManager == null) return
+
+        // Disable Bluetooth SCO (requires API 11+)
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
+            audioManager.stopBluetoothSco()
+        }
+
+        if (focusRequest != null) {
+            AudioManagerCompat.abandonAudioFocusRequest(audioManager, focusRequest!!)
+        }
     }
 }