service: handle non-native start

Restore the state by default when another app starts the service.

A simple first step to ensure service independence (no clue if it's
enough)

app/src/main/java/org/oxycblt/auxio/AuxioService.kt

@@ -20,6 +20,7 @@ package org.oxycblt.auxio
 
 import android.annotation.SuppressLint
 import android.content.Intent
+import android.os.IBinder
 import androidx.core.app.ServiceCompat
 import androidx.media3.session.MediaLibraryService
 import androidx.media3.session.MediaSession
@@ -41,6 +42,27 @@ class AuxioService : MediaLibraryService(), ForegroundListener {
         indexingFragment.attach(this)
     }
 
+    override fun onBind(intent: Intent?): IBinder? {
+        handleIntent(intent)
+        return super.onBind(intent)
+    }
+
+    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
+        // TODO: Start command occurring from a foreign service basically implies a detached
+        //  service, we might need more handling here.
+        handleIntent(intent)
+        return super.onStartCommand(intent, flags, startId)
+    }
+
+    private fun handleIntent(intent: Intent?) {
+        val nativeStart = intent?.getBooleanExtra(INTENT_KEY_NATIVE_START, false) ?: false
+        if (!nativeStart) {
+            // Some foreign code started us, no guarantees about foreground stability. Figure
+            // out what to do.
+            mediaSessionFragment.handleNonNativeStart()
+        }
+    }
+
     override fun onTaskRemoved(rootIntent: Intent?) {
         super.onTaskRemoved(rootIntent)
         mediaSessionFragment.handleTaskRemoved()
@@ -78,6 +100,11 @@ class AuxioService : MediaLibraryService(), ForegroundListener {
             }
         }
     }
+
+    companion object {
+        // This is only meant for Auxio to internally ensure that it's state management will work.
+        const val INTENT_KEY_NATIVE_START = BuildConfig.APPLICATION_ID + ".service.NATIVE_START"
+    }
 }
 
 interface ForegroundListener {

app/src/main/java/org/oxycblt/auxio/MainActivity.kt

@@ -69,7 +69,9 @@ class MainActivity : AppCompatActivity() {
     override fun onResume() {
         super.onResume()
 
-        startService(Intent(this, AuxioService::class.java))
+        startService(
+            Intent(this, AuxioService::class.java)
+                .putExtra(AuxioService.INTENT_KEY_NATIVE_START, true))
 
         if (!startIntentAction(intent)) {
             // No intent action to do, just restore the previously saved state.

app/src/main/java/org/oxycblt/auxio/playback/service/MediaSessionServiceFragment.kt

@@ -50,7 +50,9 @@ import org.oxycblt.auxio.IntegerTable
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.image.service.MediaSessionBitmapLoader
 import org.oxycblt.auxio.music.service.MediaItemBrowser
+import org.oxycblt.auxio.playback.state.DeferredPlayback
 import org.oxycblt.auxio.playback.state.PlaybackStateManager
+import org.oxycblt.auxio.util.logD
 
 class MediaSessionServiceFragment
 @Inject
@@ -103,14 +105,11 @@ constructor(
         }
     }
 
-    fun release() {
-        waitJob.cancel()
-        mediaSession.release()
-        actionHandler.release()
-        exoHolder.release()
-        playbackManager.removeListener(this)
-        mediaSession.release()
-        foregroundListener = null
+    fun handleNonNativeStart() {
+        // At minimum we want to ensure an active playback state.
+        // TODO: Possibly also force to go foreground?
+        logD("Handling non-native start.")
+        playbackManager.playDeferred(DeferredPlayback.RestoreState)
     }
 
     fun hasNotification(): Boolean = exoHolder.sessionOngoing
@@ -124,6 +123,16 @@ constructor(
         post(wrapMediaNotification(notification))
     }
 
+    fun release() {
+        waitJob.cancel()
+        mediaSession.release()
+        actionHandler.release()
+        exoHolder.release()
+        playbackManager.removeListener(this)
+        mediaSession.release()
+        foregroundListener = null
+    }
+
     private fun wrapMediaNotification(notification: MediaNotification): MediaNotification {
         // Pulled from MediaNotificationManager: Need to specify MediaSession token manually
         // in notification