fixup: add missing file

.gitignore

@@ -10,3 +10,5 @@ captures/
 *.apk
 *.ap_
 *.aab
+# David
+app/src/main/jniLibs

BUGS.md

@@ -1,6 +1,20 @@
 # Bugs
 
-- annotation playback: check what happens if some songs are not paired in the playlist. I believe the index is wrong and the player plays a different song from what is displayed as title and artist.
+- There is a bug where re-opening the app (closing it through swiping away on the android app screen, then re-opening it) will display a splash screen with the app icon large and centered, and nothing happens.
+
+	- repro:
+		- open "Run 8" playlist
+		- skip a few songs forward/backward
+		- swipe away the app in Android
+		- (LibPasada.stop() - PlaybackEngine::stop() - musicFeed->join() hangs)
+		- open app again: warm restart by Android
+		- splash screen shows app icon, hangs there
+
+- MP3File::~MP3File() must call mp3file_delete()
+
+O> (fixed on 2026-06-11) scrubber was returning 2x the time progress from PasadaMusicPlayerEngine / liblockstep
+
+X> annotation playback: check what happens if some songs are not paired in the playlist. I believe the index is wrong and the player plays a different song from what is displayed as title and artist.
 
 - syncJukeboxIfToken() is always called at startup, even if we have a jukebox already
 
@@ -23,6 +37,8 @@
 
 ## Nice-to
 
+- beat metadata is handled by the app, currently. The handling should move into "jukebox".
+
 - add a test for /playlists/<playlist_id> but obfuscate the IDs and user id
 
 - TrackFileMatching, scoreAgainstLocalHints

app/src/main/AndroidManifest.xml

@@ -20,7 +20,7 @@
         android:allowBackup="true"
         android:icon="@mipmap/ic_launcher"
         android:label="@string/app_name"
-        android:roundIcon="@mipmap/ic_launcher"
+        android:roundIcon="@mipmap/ic_launcher_round"
         android:supportsRtl="true"
         android:theme="@style/Theme.LockstepPlayer">
         <activity

app/src/main/java/at/lockstep/player/LockstepViewModel.kt

@@ -81,6 +81,13 @@ class LockstepViewModel(
             false,
         )
 
+    val feedAccelToPasada: StateFlow<Boolean> =
+        prefs.feedAccelToPasada.stateIn(
+            viewModelScope,
+            SharingStarted.Eagerly,
+            true,
+        )
+
     fun setAnnotationMode(enabled: Boolean) {
         viewModelScope.launch {
             prefs.setAnnotationMode(enabled)
@@ -93,6 +100,12 @@ class LockstepViewModel(
         }
     }
 
+    fun setFeedAccelToPasada(enabled: Boolean) {
+        viewModelScope.launch {
+            prefs.setFeedAccelToPasada(enabled)
+        }
+    }
+
     private val context get() = getApplication<Application>()
 
     /**
@@ -192,7 +205,7 @@ class LockstepViewModel(
                     context = appContext,
                     sessionFolder = sessionFolder,
                     playlistDisplayName = playlistDisplayName,
-                    trackQueueIndex0Based = event.queueIndex,
+                    trackQueueIndex0Based = event.playlistPosition,
                     contentId = contentId,
                     title = event.title,
                     artist = event.artist,
@@ -207,7 +220,7 @@ class LockstepViewModel(
                 BeatAnnotationStorage.writeBeatsFile(
                     context = appContext,
                     playlistDisplayName = playlistDisplayName,
-                    trackQueueIndex0Based = event.queueIndex,
+                    trackQueueIndex0Based = event.playlistPosition,
                     contentId = contentId,
                     title = event.title,
                     artist = event.artist,
@@ -278,7 +291,7 @@ class LockstepViewModel(
             writeRunDataAndRecordMetadata(
                 runSessionFolder = runSessionFolder,
                 playlistDisplayName = playlistDisplayName,
-                trackQueueIndex0Based = event.queueIndex,
+                trackQueueIndex0Based = event.playlistPosition,
                 trackId = event.trackId,
                 metaContentUri = meta,
                 title = event.title,
@@ -296,7 +309,7 @@ class LockstepViewModel(
         trackId: String,
         title: String,
         artist: String,
-        queueIndex: Int,
+        playlistPosition: Int,
         snapshot: RunTrackDataSnapshot,
     ) {
         if (snapshot.isEmpty()) {
@@ -308,7 +321,7 @@ class LockstepViewModel(
             writeRunDataAndRecordMetadata(
                 runSessionFolder = runSessionFolder,
                 playlistDisplayName = playlistDisplayName,
-                trackQueueIndex0Based = queueIndex,
+                trackQueueIndex0Based = playlistPosition,
                 trackId = trackId,
                 metaContentUri = meta,
                 title = title,
@@ -453,6 +466,22 @@ class LockstepViewModel(
         }
     }
 
+    /** Set before popping Now Playing; [consumeSuppressNextLibraryMetadataSync] skips one Library batch sync. */
+    @Volatile
+    private var suppressNextLibraryMetadataSync = false
+
+    fun suppressNextLibraryMetadataSync() {
+        suppressNextLibraryMetadataSync = true
+    }
+
+    fun consumeSuppressNextLibraryMetadataSync(): Boolean {
+        if (!suppressNextLibraryMetadataSync) {
+            return false
+        }
+        suppressNextLibraryMetadataSync = false
+        return true
+    }
+
     suspend fun syncPendingMetadata(): String? {
         val token = spotifyAccessToken.value
         if (token.isNullOrBlank()) {
@@ -546,13 +575,34 @@ class LockstepViewModel(
                 app.playlistRepository.syncPlaylistDetail(playlistId)
                 null
             } catch (e: LockstepApiException) {
-                e.message ?: "Load failed"
+                syncPlaylistDetailErrorForLibraryOpen(playlistId, e)
             } catch (e: IOException) {
-                e.message ?: "Load failed"
+                syncPlaylistDetailErrorForLibraryOpen(playlistId, e)
             }
         }
     }
 
+    /**
+     * Playlist detail fetch is best-effort when opening from the library. Unauthorized responses mean
+     * the token is stale; cached jukebox rows (if any) are still valid for pairing and playback.
+     */
+    private fun syncPlaylistDetailErrorForLibraryOpen(playlistId: String, e: Exception): String? {
+        if (isPlaylistDetailHttp401(e)) {
+            Log.w(TAG, "syncPlaylistDetail unauthorized for $playlistId, opening from jukebox cache", e)
+            return null
+        }
+        if (app.playlistRepository.getTracks(playlistId).isNotEmpty()) {
+            Log.w(TAG, "syncPlaylistDetail failed for $playlistId, using cached tracks", e)
+            return null
+        }
+        return e.message ?: "Load failed"
+    }
+
+    private fun isPlaylistDetailHttp401(e: Exception): Boolean {
+        val msg = e.message ?: return false
+        return msg.contains("HTTP 401", ignoreCase = true)
+    }
+
     fun completeOnboarding() {
         viewModelScope.launch {
             prefs.setOnboardingComplete(true)

app/src/main/java/at/lockstep/player/data/UserPreferencesRepository.kt

@@ -39,6 +39,12 @@ class UserPreferencesRepository(
             prefs[KEY_COLLECT_RUN_DATA] == true
         }
 
+    /** When true, accelerometer samples are forwarded to libpasada during playback (not while annotating). */
+    val feedAccelToPasada: Flow<Boolean> =
+        dataStore.data.map { prefs ->
+            prefs[KEY_FEED_ACCEL_TO_PASADA] != false
+        }
+
     suspend fun setOnboardingComplete(done: Boolean) {
         dataStore.edit { prefs ->
             prefs[KEY_ONBOARDING_COMPLETE] = done
@@ -67,10 +73,17 @@ class UserPreferencesRepository(
         }
     }
 
+    suspend fun setFeedAccelToPasada(enabled: Boolean) {
+        dataStore.edit { prefs ->
+            prefs[KEY_FEED_ACCEL_TO_PASADA] = enabled
+        }
+    }
+
     companion object {
         private val KEY_ONBOARDING_COMPLETE = booleanPreferencesKey("onboarding_complete")
         private val KEY_SPOTIFY_ACCESS_TOKEN = stringPreferencesKey("spotify_access_token")
         private val KEY_ANNOTATION_MODE = booleanPreferencesKey("annotation_mode")
         private val KEY_COLLECT_RUN_DATA = booleanPreferencesKey("collect_run_data")
+        private val KEY_FEED_ACCEL_TO_PASADA = booleanPreferencesKey("feed_accel_to_pasada")
     }
 }

app/src/main/java/at/lockstep/player/pasada/LibPasada.java

@@ -21,7 +21,7 @@ public final class LibPasada {
         if (loaded) {
             return;
         }
-        System.loadLibrary("pasada");
+        System.loadLibrary("lockstep-native");
         loaded = true;
     }
 
@@ -37,8 +37,14 @@ public final class LibPasada {
      * @param fd open read FD (Java retains ownership; do not close until track changes)
      * @param offset start offset within the FD (0 for whole file)
      * @param length byte length from offset ({@code -1} if unknown / to EOF)
+     * @param beatTimesSec beat times in seconds from track start, or {@code null} when unknown
      */
-    public static native void play(int fd, long offset, long length);
+    public static native void play(int fd, long offset, long length, double[] beatTimesSec);
+
+    /** Same as {@link #play(int, long, long, double[])} with no beat annotation. */
+    public static void play(int fd, long offset, long length) {
+        play(fd, offset, length, null);
+    }
 
     /** PLAYING → PAUSED (silent output, graph kept alive). */
     public static native void pause();
@@ -72,4 +78,7 @@ public final class LibPasada {
 
     /** Register listener for async events raised from the audio/native thread. */
     public static native void setPlaybackListener(PasadaPlaybackListener listener);
+
+    /** native version string */
+    public static native String getVersion();
 }

app/src/main/java/at/lockstep/player/pasada/PasadaPlaybackListener.java

@@ -9,6 +9,8 @@ public interface PasadaPlaybackListener {
     /** Current track reached end; service should advance queue and call {@link LibPasada#play}. */
     void onTrackFinished();
 
+    void onTrackClosed(int fd);
+
     /** Decode / Oboe / pipeline failure; service should stop safely and surface error. */
     void onError(int errorCode, String message);
 }

app/src/main/java/at/lockstep/player/playback/PasadaAccelFeeder.kt

@@ -0,0 +1,77 @@
+package at.lockstep.player.playback
+
+import android.content.Context
+import android.hardware.Sensor
+import android.hardware.SensorEvent
+import android.hardware.SensorEventListener
+import android.hardware.SensorManager
+import android.os.Handler
+import android.os.HandlerThread
+import at.lockstep.player.pasada.LibPasada
+
+/**
+ * Registers the accelerometer on a background [HandlerThread] and forwards samples to
+ * [LibPasada.feedAccel]. Owned by [PlaybackService] for the duration of a run session.
+ */
+class PasadaAccelFeeder(
+    context: Context,
+) {
+    private val sensorManager = context.applicationContext.getSystemService(SensorManager::class.java)
+    private val accelerometer = sensorManager?.getDefaultSensor(Sensor.TYPE_ACCELEROMETER)
+    private val handlerThread = HandlerThread("PasadaAccel").apply { start() }
+    private val handler = Handler(handlerThread.looper)
+
+    @Volatile
+    private var feedingEnabled = false
+
+    private var registered = false
+
+    private val listener =
+        object : SensorEventListener {
+            override fun onSensorChanged(event: SensorEvent) {
+                if (!feedingEnabled || event.sensor.type != Sensor.TYPE_ACCELEROMETER) {
+                    return
+                }
+                LibPasada.feedAccel(
+                    event.values[0],
+                    event.values[1],
+                    event.values[2],
+                    event.timestamp,
+                )
+            }
+
+            override fun onAccuracyChanged(
+                sensor: Sensor?,
+                accuracy: Int,
+            ) = Unit
+        }
+
+    fun start() {
+        if (registered || sensorManager == null || accelerometer == null) {
+            return
+        }
+        feedingEnabled = true
+        sensorManager.registerListener(
+            listener,
+            accelerometer,
+            SensorManager.SENSOR_DELAY_GAME,
+            0,
+            handler,
+        )
+        registered = true
+    }
+
+    fun stop() {
+        feedingEnabled = false
+        if (!registered || sensorManager == null) {
+            return
+        }
+        sensorManager.unregisterListener(listener)
+        registered = false
+    }
+
+    fun release() {
+        stop()
+        handlerThread.quitSafely()
+    }
+}

app/src/main/java/at/lockstep/player/playback/PlaybackService.kt

@@ -16,8 +16,11 @@ import androidx.media.app.NotificationCompat.MediaStyle
 import at.lockstep.player.LockstepApplication
 import at.lockstep.player.MainActivity
 import at.lockstep.player.R
+import at.lockstep.player.data.db.FileMetadataEntity
 import at.lockstep.player.playback.engine.ExoPlayerMusicPlayerEngine
+import at.lockstep.player.playback.engine.PasadaMusicPlayerEngine
 import at.lockstep.player.playback.engine.MusicPlayerEngine
+import at.lockstep.player.util.BeatAnnotationStorage
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.Job
@@ -47,9 +50,18 @@ class PlaybackService : Service() {
     private val binder = LocalBinder()
 
     private var engine: MusicPlayerEngine? = null
+    private var accelFeeder: PasadaAccelFeeder? = null
     private var positionPollJob: Job? = null
     private var positionCachePollJob: Job? = null
 
+    /** User preference: forward accelerometer samples to libpasada. */
+    @Volatile
+    private var feedAccelEnabled = true
+
+    /** True while the beat annotation screen is visible. */
+    @Volatile
+    private var isAnnotating = false
+
     private val _uiState = MutableStateFlow(PlaybackUiState.initial())
     val uiState: StateFlow<PlaybackUiState> = _uiState.asStateFlow()
 
@@ -110,6 +122,7 @@ class PlaybackService : Service() {
                             title = item.title,
                             artist = item.artist,
                             queueIndex = i,
+                            playlistPosition = item.playlistPosition,
                             queueSize = queue.size,
                             reason = reason,
                     ),
@@ -203,15 +216,50 @@ class PlaybackService : Service() {
         engine?.let {
             return it
         }
-        return ExoPlayerMusicPlayerEngine(this)
+        //return ExoPlayerMusicPlayerEngine(this)
+        return PasadaMusicPlayerEngine(this)
             .also {
                 it.setListener(engineListener)
                 it.initSession()
                 engine = it
+                refreshAccelFeeding()
                 startPositionPolling()
             }
     }
 
+    /** Called when the user toggles "Adapt playback to movement" in Settings. */
+    fun setFeedAccelEnabled(enabled: Boolean) {
+        feedAccelEnabled = enabled
+        refreshAccelFeeding()
+    }
+
+    /** Called when entering or leaving the beat annotation screen. */
+    fun setAnnotating(annotating: Boolean) {
+        isAnnotating = annotating
+        refreshAccelFeeding()
+    }
+
+    private fun refreshAccelFeeding() {
+        if (engine == null) {
+            return
+        }
+        if (feedAccelEnabled && !isAnnotating) {
+            startAccelFeeding()
+        } else {
+            stopAccelFeeding()
+        }
+    }
+
+    private fun startAccelFeeding() {
+        val feeder =
+            accelFeeder ?: PasadaAccelFeeder(this).also { accelFeeder = it }
+        feeder.start()
+    }
+
+    private fun stopAccelFeeding() {
+        accelFeeder?.stop()
+    }
+
     private fun startPositionPolling() {
         positionPollJob?.cancel()
         positionPollJob =
@@ -238,6 +286,7 @@ class PlaybackService : Service() {
         positionPollJob = null
         positionCachePollJob?.cancel()
         positionCachePollJob = null
+        stopAccelFeeding()
         engine?.setListener(null)
         engine?.releaseSession()
         engine = null
@@ -265,6 +314,7 @@ class PlaybackService : Service() {
                         artist = row.artistName ?: "—",
                         localUri = Uri.parse(uriStr),
                         durationMsHint = hint,
+                        playlistPosition = row.position,
                     )
                 }
             index = 0
@@ -287,31 +337,59 @@ class PlaybackService : Service() {
 
     private fun publishCurrentTrack() {
         val item = queue.getOrNull(index) ?: return
-        applyCurrentMediaItem(item)
+        scope.launch {
+            val beatTimesSec =
+                withContext(Dispatchers.IO) {
+                    loadBeatTimesSecForTrack(item.id)
+                }
+            withContext(Dispatchers.Main) {
+                val current = queue.getOrNull(index) ?: return@withContext
+                if (current.id != item.id) {
+                    return@withContext
+                }
+                applyCurrentMediaItem(current, beatTimesSec)
                 val durationSec =
                     (engine?.getDurationMs()?.takeIf { it > 0 }?.div(1000)?.toInt())
-                ?: (item.durationMsHint / 1000).coerceAtLeast(1)
+                        ?: (current.durationMsHint / 1000).coerceAtLeast(1)
                 _uiState.value =
                     PlaybackUiState(
-                title = item.title,
-                artist = item.artist,
+                        title = current.title,
+                        artist = current.artist,
                         progress = 0f,
                         durationSeconds = durationSec,
                         isPlaying = _uiState.value.isPlaying,
-                currentTrackId = item.id,
+                        currentTrackId = current.id,
                         currentQueueIndex = index,
+                        currentPlaylistPosition = current.playlistPosition,
                         queueSize = queue.size,
                     )
                 updateProgressFromEngine()
-        updateSessionMetadata(item, durationSec)
+                updateSessionMetadata(current, durationSec)
                 updatePlaybackStateFromEngine()
                 refreshForegroundNotification()
             }
+        }
+    }
 
-    private fun applyCurrentMediaItem(item: TrackQueueItem) {
+    private suspend fun loadBeatTimesSecForTrack(trackId: String): DoubleArray? {
+        val metadata =
+            app.database.fileMetadataDao().findByTrackIdAndType(
+                trackId,
+                FileMetadataEntity.TYPE_BEATS,
+            ) ?: return null
+        if (metadata.fileUri.isBlank()) {
+            return null
+        }
+        return BeatAnnotationStorage.readBeatTimesSec(app, metadata.fileUri)
+    }
+
+    private fun applyCurrentMediaItem(
+        item: TrackQueueItem,
+        beatTimesSec: DoubleArray?,
+    ) {
         val uri = item.localUri ?: return
         val e = ensureEngine()
-        e.prepareTrack(uri)
+        e.prepareTrack(uri, beatTimesSec)
         if (_uiState.value.isPlaying) {
             e.play()
         } else {
@@ -367,6 +445,8 @@ class PlaybackService : Service() {
                 durationSeconds = durationSec,
                 currentTrackId = queue.getOrNull(index)?.id ?: _uiState.value.currentTrackId,
                 currentQueueIndex = index,
+                currentPlaylistPosition =
+                    queue.getOrNull(index)?.playlistPosition ?: _uiState.value.currentPlaylistPosition,
                 queueSize = queue.size,
             )
         updatePlaybackStateFromEngine()
@@ -533,6 +613,8 @@ class PlaybackService : Service() {
 
     override fun onDestroy() {
         stopPlaybackAndTeardown()
+        accelFeeder?.release()
+        accelFeeder = null
         super.onDestroy()
     }
 
@@ -566,6 +648,8 @@ class PlaybackService : Service() {
         val isPlaying: Boolean,
         val currentTrackId: String?,
         val currentQueueIndex: Int,
+        /** 0-based position in the full Spotify playlist for the current track. */
+        val currentPlaylistPosition: Int,
         val queueSize: Int,
     ) {
         companion object {
@@ -578,6 +662,7 @@ class PlaybackService : Service() {
                     isPlaying = false,
                     currentTrackId = null,
                     currentQueueIndex = 0,
+                    currentPlaylistPosition = 0,
                     queueSize = 0,
                 )
         }
@@ -590,6 +675,8 @@ class PlaybackService : Service() {
         val localUri: Uri?,
         /** Fallback when the engine has not reported duration yet (from jukebox or default). */
         val durationMsHint: Int,
+        /** 0-based position in the full Spotify playlist. */
+        val playlistPosition: Int,
     )
 
     companion object {

app/src/main/java/at/lockstep/player/playback/TrackBoundaryEvent.kt

@@ -8,8 +8,10 @@ data class TrackBoundaryEvent(
     val trackId: String,
     val title: String,
     val artist: String,
-    /** 0-based index in the current play queue when this track was current. */
+    /** 0-based index in the paired-only play queue when this track was current. */
     val queueIndex: Int,
+    /** 0-based position in the full Spotify playlist (used for beat/run-data file slots). */
+    val playlistPosition: Int,
     val queueSize: Int,
     val reason: TrackBoundaryReason,
 )

app/src/main/java/at/lockstep/player/playback/engine/ExoPlayerMusicPlayerEngine.kt

@@ -33,7 +33,10 @@ class ExoPlayerMusicPlayerEngine(
                 .also { it.addListener(playerListener) }
     }
 
-    override fun prepareTrack(uri: Uri) {
+    override fun prepareTrack(
+        uri: Uri,
+        beatTimesSec: DoubleArray?,
+    ) {
         val p = requirePlayer()
         p.setMediaItem(MediaItem.fromUri(uri))
         p.prepare()

app/src/main/java/at/lockstep/player/playback/engine/MusicPlayerEngine.kt

@@ -14,7 +14,13 @@ interface MusicPlayerEngine {
      * Load a track from a local URI. Asynchronous — playback starts after prepare when [play] is
      * called (or immediately if [playWhenReady] is set via [play]).
      */
-    fun prepareTrack(uri: Uri)
+    /**
+     * @param beatTimesSec optional beat times in seconds from [TYPE_BEATS] metadata; passed to libpasada on play.
+     */
+    fun prepareTrack(
+        uri: Uri,
+        beatTimesSec: DoubleArray? = null,
+    )
 
     fun play()
 

app/src/main/java/at/lockstep/player/playback/engine/PasadaMusicPlayerEngine.kt

@@ -6,6 +6,7 @@ import android.net.Uri
 import android.os.Handler
 import android.os.Looper
 import android.os.ParcelFileDescriptor
+import android.util.Log
 import at.lockstep.player.pasada.LibPasada
 import at.lockstep.player.pasada.PasadaPlaybackListener
 import java.io.IOException
@@ -26,6 +27,7 @@ class PasadaMusicPlayerEngine(
     private var trackFd: Int? = null
     private var trackOffset: Long = 0L
     private var trackLength: Long = -1L
+    private var pendingBeatTimesSec: DoubleArray? = null
 
     /** FD is open but [LibPasada.play] has not been called yet for this track. */
     private var pendingStart = false
@@ -35,12 +37,18 @@ class PasadaMusicPlayerEngine(
     private val nativeListener =
         object : PasadaPlaybackListener {
             override fun onTrackFinished() {
+                Log.i(TAG, "PasadaPlaybackListener.onTrackFinished()")
                 pendingStart = false
                 mainHandler.post {
                     listener?.onPlaybackEnded()
                 }
             }
 
+            override fun onTrackClosed(fd: Int) {
+                Log.i(TAG, "onTrackClosed: native returned fd=$fd")
+                // we handle parcel close() separately
+            }
+
             override fun onError(
                 errorCode: Int,
                 message: String,
@@ -51,20 +59,29 @@ class PasadaMusicPlayerEngine(
             }
         }
 
+    val TAG = "PasadaMusicPlayerEngine"
+
     override fun initSession() {
         if (sessionInitialized) {
             return
         }
+        Log.i(TAG, "LibPasada.loadNative() ...")
         LibPasada.loadNative()
         LibPasada.setPlaybackListener(nativeListener)
+        Log.i(TAG, "LibPasada.init() ...")
         LibPasada.init()
+        Log.i(TAG, "LibPasada.init() done.")
         sessionInitialized = true
     }
 
-    override fun prepareTrack(uri: Uri) {
+    override fun prepareTrack(
+        uri: Uri,
+        beatTimesSec: DoubleArray?,
+    ) {
         closeOpenTrack()
         try {
             openTrack(uri)
+            pendingBeatTimesSec = beatTimesSec
             pendingStart = true
         } catch (e: IOException) {
             closeOpenTrack()
@@ -119,8 +136,11 @@ class PasadaMusicPlayerEngine(
     override fun releaseSession() {
         closeOpenTrack()
         if (sessionInitialized) {
-            LibPasada.setPlaybackListener(null)
+            Log.i(TAG, "LibPasada.stop() ...")
             LibPasada.stop()
+            Log.i(TAG, "LibPasada.stop() done.")
+            LibPasada.setPlaybackListener(null)
+            Log.i(TAG, "LibPasada.setPlaybackListener(null) done.")
             sessionInitialized = false
         }
     }
@@ -131,7 +151,14 @@ class PasadaMusicPlayerEngine(
 
     private fun startPendingTrack() {
         val fd = trackFd ?: return
-        LibPasada.play(fd, trackOffset, trackLength)
+        val beats = pendingBeatTimesSec
+        Log.i(
+            TAG,
+            "LibPasada.play(fd=$fd, offset=$trackOffset, length=$trackLength, beats=${beats?.size ?: 0}) ...",
+        )
+        LibPasada.play(fd, trackOffset, trackLength, beats)
+        Log.i(TAG, "LibPasada.play() done.")
+        pendingBeatTimesSec = null
         pendingStart = false
     }
 
@@ -165,6 +192,7 @@ class PasadaMusicPlayerEngine(
         trackFd = null
         trackOffset = 0L
         trackLength = -1L
+        pendingBeatTimesSec = null
         pendingStart = false
     }
 

app/src/main/java/at/lockstep/player/ui/AnnotationScreen.kt

@@ -24,6 +24,7 @@ import androidx.compose.material3.Scaffold
 import androidx.compose.material3.Text
 import androidx.compose.material3.TopAppBar
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.DisposableEffect
 import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateListOf
@@ -85,23 +86,34 @@ fun AnnotationRoute(
         }
     }
 
+    DisposableEffect(playback) {
+        playback?.setAnnotating(true)
+        onDispose {
+            playback?.setAnnotating(false)
+        }
+    }
+
     val beatTimesMs = remember { mutableStateListOf<Long>() }
     val annotationSessionFolder = remember { RunDataStorage.newRunSessionFolderName() }
 
     var playlistDisplayName by remember { mutableStateOf("playlist") }
 
     LaunchedEffect(playlistId) {
-        playlistDisplayName = viewModel.getPlaylistDisplayName(playlistId)
+        val name = viewModel.getPlaylistDisplayName(playlistId)
+        playlistDisplayName = name
+        viewModel.fetchBeatsMetadataForPlaylist(playlistId, name)
     }
 
-    LaunchedEffect(playback, playlistId, playlistDisplayName, annotationSessionFolder) {
+    LaunchedEffect(playback, playlistId, annotationSessionFolder) {
         val service = playback ?: return@LaunchedEffect
+        val name = viewModel.getPlaylistDisplayName(playlistId)
+        playlistDisplayName = name
         service.trackBoundaryEvents.collect { event ->
             val snapshot = beatTimesMs.toList()
             beatTimesMs.clear()
             viewModel.persistBeatAnnotation(
                 playlistId,
-                playlistDisplayName,
+                name,
                 annotationSessionFolder,
                 event,
                 snapshot,

app/src/main/java/at/lockstep/player/ui/LockstepAppNavHost.kt

@@ -8,6 +8,7 @@ import android.os.IBinder
 import androidx.activity.ComponentActivity
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.DisposableEffect
+import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
@@ -34,8 +35,13 @@ fun LockstepAppNavHost(
     viewModel: LockstepViewModel,
 ) {
     val annotationMode by viewModel.annotationMode.collectAsStateWithLifecycle()
+    val feedAccelToPasada by viewModel.feedAccelToPasada.collectAsStateWithLifecycle()
     var playback by remember { mutableStateOf<PlaybackService?>(null) }
 
+    LaunchedEffect(feedAccelToPasada, playback) {
+        playback?.setFeedAccelEnabled(feedAccelToPasada)
+    }
+
     DisposableEffect(Unit) {
         val connection =
             object : ServiceConnection {
@@ -116,7 +122,10 @@ fun LockstepAppNavHost(
                 playlistId = playlistId,
                 playback = playback,
                 viewModel = viewModel,
-                onBack = { navController.popBackStack() },
+                onBack = {
+                    viewModel.suppressNextLibraryMetadataSync()
+                    navController.popBackStack()
+                },
             )
         }
         composable(

app/src/main/java/at/lockstep/player/ui/NowPlayingScreen.kt

@@ -2,6 +2,7 @@ package at.lockstep.player.ui
 
 import android.Manifest
 import android.content.pm.PackageManager
+import androidx.activity.compose.BackHandler
 import androidx.activity.compose.rememberLauncherForActivityResult
 import androidx.activity.result.contract.ActivityResultContracts
 import androidx.compose.foundation.layout.Arrangement
@@ -169,6 +170,7 @@ fun NowPlayingRoute(
     modifier: Modifier = Modifier,
 ) {
     val context = LocalContext.current
+    BackHandler(onBack = onBack)
     val collectRunData by viewModel.collectRunData.collectAsStateWithLifecycle()
     val collector = remember { RunDataCollector(context) }
     val runSessionFolder = remember { RunDataStorage.newRunSessionFolderName() }
@@ -194,7 +196,7 @@ fun NowPlayingRoute(
     }
     var playlistDisplayName by remember { mutableStateOf("playlist") }
     var currentTrackId by remember { mutableStateOf<String?>(null) }
-    var currentQueueIndex by remember { mutableIntStateOf(0) }
+    var currentPlaylistPosition by remember { mutableIntStateOf(0) }
 
     var ui by remember {
         mutableStateOf(
@@ -210,18 +212,16 @@ fun NowPlayingRoute(
     }
 
     LaunchedEffect(playlistId) {
-        playlistDisplayName = viewModel.getPlaylistDisplayName(playlistId)
-    }
-
-    LaunchedEffect(playlistId, playlistDisplayName) {
-        viewModel.fetchBeatsMetadataForPlaylist(playlistId, playlistDisplayName)
+        val name = viewModel.getPlaylistDisplayName(playlistId)
+        playlistDisplayName = name
+        viewModel.fetchBeatsMetadataForPlaylist(playlistId, name)
     }
 
     LaunchedEffect(playback) {
         val service = playback ?: return@LaunchedEffect
         service.uiState.collect { p ->
             currentTrackId = p.currentTrackId
-            currentQueueIndex = p.currentQueueIndex
+            currentPlaylistPosition = p.currentPlaylistPosition
             ui =
                 NowPlayingUiState(
                     title = p.title,
@@ -234,6 +234,11 @@ fun NowPlayingRoute(
         }
     }
 
+    DisposableEffect(playback) {
+        playback?.setAnnotating(false)
+        onDispose { }
+    }
+
     LaunchedEffect(collectRunData, playback) {
         if (!collectRunData) {
             collector.setCollectingEnabled(false)
@@ -255,12 +260,14 @@ fun NowPlayingRoute(
         }
     }
 
-    LaunchedEffect(collectRunData, playback, playlistId, playlistDisplayName) {
+    LaunchedEffect(collectRunData, playback, playlistId) {
         if (!collectRunData) return@LaunchedEffect
         val service = playback ?: return@LaunchedEffect
+        val name = viewModel.getPlaylistDisplayName(playlistId)
+        playlistDisplayName = name
         service.trackBoundaryEvents.collect { event ->
             val snapshot = collector.snapshotAndClear()
-            viewModel.persistRunData(playlistId, playlistDisplayName, runSessionFolder, event, snapshot)
+            viewModel.persistRunData(playlistId, name, runSessionFolder, event, snapshot)
         }
     }
 
@@ -283,7 +290,7 @@ fun NowPlayingRoute(
                         trackId = trackId,
                         title = ui.title,
                         artist = ui.artist,
-                        queueIndex = currentQueueIndex,
+                        playlistPosition = currentPlaylistPosition,
                         snapshot = snapshot,
                     )
                 }

app/src/main/java/at/lockstep/player/ui/library/LibraryScreen.kt

@@ -49,10 +49,11 @@ fun LibraryScreen(
 
     LaunchedEffect(token) {
         if (token.isNullOrBlank()) return@LaunchedEffect
+        val skipMetadataSync = viewModel.consumeSuppressNextLibraryMetadataSync()
         val errors =
             listOfNotNull(
                 viewModel.syncJukeboxIfToken(),
-                viewModel.syncPendingMetadata(),
+                if (skipMetadataSync) null else viewModel.syncPendingMetadata(),
             )
         if (errors.isNotEmpty()) {
             Toast.makeText(context, errors.joinToString("\n"), Toast.LENGTH_LONG).show()

app/src/main/java/at/lockstep/player/ui/settings/SettingsScreen.kt

@@ -38,6 +38,7 @@ fun SettingsScreen(
     val context = LocalContext.current
     val annotationMode by viewModel.annotationMode.collectAsStateWithLifecycle()
     val collectRunData by viewModel.collectRunData.collectAsStateWithLifecycle()
+    val feedAccelToPasada by viewModel.feedAccelToPasada.collectAsStateWithLifecycle()
     Scaffold(
         modifier = modifier.fillMaxSize(),
         topBar = {
@@ -83,6 +84,30 @@ fun SettingsScreen(
                     onCheckedChange = { viewModel.setAnnotationMode(it) },
                 )
             }
+            Row(
+                modifier =
+                    Modifier
+                        .fillMaxWidth()
+                        .padding(vertical = 8.dp),
+                verticalAlignment = Alignment.CenterVertically,
+                horizontalArrangement = Arrangement.SpaceBetween,
+            ) {
+                Column(modifier = Modifier.weight(1f).padding(end = 16.dp)) {
+                    Text(
+                        text = context.getString(R.string.settings_feed_accel_to_pasada),
+                        style = MaterialTheme.typography.titleMedium,
+                    )
+                    Text(
+                        text = context.getString(R.string.settings_feed_accel_to_pasada_help),
+                        style = MaterialTheme.typography.bodySmall,
+                        color = MaterialTheme.colorScheme.onSurfaceVariant,
+                    )
+                }
+                Switch(
+                    checked = feedAccelToPasada,
+                    onCheckedChange = { viewModel.setFeedAccelToPasada(it) },
+                )
+            }
             Row(
                 modifier =
                     Modifier

app/src/main/java/at/lockstep/player/util/BeatAnnotationStorage.kt

@@ -62,6 +62,25 @@ object BeatAnnotationStorage {
         return RunDataStorage.writeOrReplacePublicJsonFile(context, relativePath, fileName, jsonString)
     }
 
+    /** Reads [beatTimesSec] from a beats or annotation JSON file; {@code null} if missing or unreadable. */
+    fun readBeatTimesSec(
+        context: Context,
+        fileUri: String,
+    ): DoubleArray? {
+        if (fileUri.isBlank()) {
+            return null
+        }
+        return try {
+            context.contentResolver.openInputStream(Uri.parse(fileUri))?.use { stream ->
+                val json = JSONObject(stream.bufferedReader().readText())
+                val arr = json.optJSONArray("beatTimesSec") ?: return null
+                DoubleArray(arr.length()) { i -> arr.getDouble(i) }
+            }
+        } catch (_: Exception) {
+            null
+        }
+    }
+
     fun buildAnnotationJson(
         contentId: String,
         title: String,

app/src/main/java/com/rex/logger/NdkLogger.java

@@ -0,0 +1,64 @@
+/*
+ *  Licensed to the Apache Software Foundation (ASF) under one or more
+ *  contributor license agreements.  See the NOTICE file distributed with
+ *  this work for additional information regarding copyright ownership.
+ *  The ASF licenses this file to You under the Apache License, Version 2.0
+ *  (the "License"); you may not use this file except in compliance with
+ *  the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package com.rex.logger;
+
+import android.util.Log;
+
+//import proguard.annotation.KeepName;
+
+//@KeepName
+
+/**
+ * Gather native log into logback, for easy control save log into SDCard
+ */
+public class NdkLogger {
+    private static final String TAG = "NDK";
+
+    //@KeepName
+    public static void logWrite(int level, String message) {
+        //sLogger.trace("level:{} message:{}", level, message);
+        switch (level) {
+            case Log.VERBOSE:
+                Log.v(TAG, message);
+                break;
+            case Log.DEBUG:
+                Log.d(TAG, message);
+                break;
+            case Log.INFO:
+                Log.i(TAG, message);
+                break;
+            case Log.WARN:
+                Log.w(TAG, message);
+                break;
+            case Log.ERROR:
+                Log.e(TAG, message);
+                break;
+        }
+    }
+
+    static {
+        try {
+            System.loadLibrary("ndk-logger");
+        } catch (UnsatisfiedLinkError ex) {
+            Log.e(TAG, "Failed to load library.", ex);
+        }
+    }
+
+    public static String getABI() { return native_getABI(); }
+    private static native String native_getABI();
+}

app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@color/ic_launcher_bg" />
+    <foreground android:drawable="@mipmap/ic_launcher_foreground" />
+</adaptive-icon>

app/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@color/ic_launcher_bg" />
+    <foreground android:drawable="@mipmap/ic_launcher_foreground" />
+</adaptive-icon>

app/src/main/res/values/strings.xml

@@ -32,6 +32,8 @@
     <string name="settings_annotation_mode_help">When enabled, choosing a playlist opens beat annotation (tap in time) instead of Now playing.</string>
     <string name="settings_collect_run_data">Collect run data</string>
     <string name="settings_collect_run_data_help">When enabled, Now playing records accelerometer, gyroscope, and GPS (1 Hz) per song into Documents/Pasada/ under a timestamped run folder.</string>
+    <string name="settings_feed_accel_to_pasada">Adapt playback to movement</string>
+    <string name="settings_feed_accel_to_pasada_help">When enabled, accelerometer data is sent to libpasada during Now playing so tempo can follow your pace. Disabled automatically on the beat annotation screen.</string>
     <string name="annotation_title">Beat annotation</string>
     <string name="annotation_subtitle">Tap on each beat; times use the same clock as playback (ExoPlayer position).</string>
     <string name="annotation_tap_area_label">Tap here on the beat</string>

scripts/generate_launcher_icons.py

@@ -0,0 +1,53 @@
+"""Downscale launcher icon PNGs from mipmap-xxxhdpi masters to lower densities."""
+from __future__ import annotations
+
+from pathlib import Path
+
+from PIL import Image
+
+ROOT = Path(__file__).resolve().parents[1]
+RES = ROOT / "app" / "src" / "main" / "res"
+SOURCE_FOLDER = "mipmap-xxxhdpi"
+
+SOURCES = {
+    "ic_launcher.png": {
+        "mipmap-xxxhdpi": 192,
+        "mipmap-xxhdpi": 144,
+        "mipmap-xhdpi": 96,
+        "mipmap-hdpi": 72,
+        "mipmap-mdpi": 48,
+    },
+    "ic_launcher_foreground.png": {
+        "mipmap-xxxhdpi": 432,
+        "mipmap-xxhdpi": 324,
+        "mipmap-xhdpi": 216,
+        "mipmap-hdpi": 162,
+        "mipmap-mdpi": 108,
+    },
+}
+
+
+def main() -> None:
+    for filename, sizes in SOURCES.items():
+        source_path = RES / SOURCE_FOLDER / filename
+        source = Image.open(source_path)
+        expected = sizes[SOURCE_FOLDER]
+        if source.size != (expected, expected):
+            raise RuntimeError(
+                f"{source_path} is {source.size[0]}x{source.size[1]}, expected {expected}x{expected}"
+            )
+
+        for folder, size in sizes.items():
+            if folder == SOURCE_FOLDER:
+                continue
+            out_dir = RES / folder
+            out_dir.mkdir(parents=True, exist_ok=True)
+            resized = source.resize((size, size), Image.Resampling.LANCZOS)
+            resized.save(out_dir / filename)
+            print(f"Wrote {folder}/{filename} ({size}x{size})")
+
+    print("Done.")
+
+
+if __name__ == "__main__":
+    main()