# Media3 Migration + Android Auto Implementation Plan

> **For Claude:** REQUIRED SUB-SKILL: Use superpowers:executing-plans to implement this plan task-by-task.

**Goal:** Replace legacy MediaSessionCompat with Media3 MediaLibraryService to get proper system media notifications (with metadata + album art) and Android Auto browsing support.

**Architecture:** A thin `RadioPlayerAdapter` implements Media3's `Player` interface as a facade over the existing custom audio engine. `RadioPlaybackService` converts from `LifecycleService` to `MediaLibraryService`, which auto-manages notifications and exposes a browse tree for Android Auto. The custom audio pipeline (OkHttp → IcyParser → MediaCodec → AudioTrack) is untouched.

**Tech Stack:** Kotlin, Media3 1.6.0 (media3-session, media3-common), Room, Coroutines

**Design doc:** `docs/plans/2026-03-18-media3-android-auto-design.md`

---

### Task 1: Update Dependencies

**Files:**
- Modify: `gradle/libs.versions.toml`
- Modify: `app/build.gradle.kts`

**Step 1: Add Media3 to version catalog**

In `gradle/libs.versions.toml`, add version and libraries:

```toml
# In [versions], add:
media3 = "1.6.0"

# In [libraries], add:
media3-session = { group = "androidx.media3", name = "media3-session", version.ref = "media3" }
media3-common = { group = "androidx.media3", name = "media3-common", version.ref = "media3" }

# In [libraries], remove:
# media-session = { group = "androidx.media", name = "media", version.ref = "media" }

# In [versions], remove:
# media = "1.7.1"
```

**Step 2: Swap dependencies in build.gradle.kts**

In `app/build.gradle.kts`, replace:

```kotlin
// Remove:
implementation(libs.media.session)

// Add:
implementation(libs.media3.session)
implementation(libs.media3.common)
```

Also remove `implementation(libs.lifecycle.service)` — `MediaLibraryService` does not extend `LifecycleService`.

**Step 3: Verify build compiles (expect errors)**

Run: `./gradlew :app:compileDebugKotlin 2>&1 | tail -20`

Expected: Compilation errors in `RadioPlaybackService.kt` and `NotificationHelper.kt` because they reference `MediaSessionCompat` and `LifecycleService`. This is expected — we'll fix them in subsequent tasks.

**Step 4: Commit**

```bash
git add gradle/libs.versions.toml app/build.gradle.kts
git commit -m "chore: swap androidx.media for media3-session + media3-common"
```

---

### Task 2: Add Manifest + Automotive Config

**Files:**
- Modify: `app/src/main/AndroidManifest.xml`
- Create: `app/src/main/res/xml/automotive_app.xml`

**Step 1: Create automotive_app.xml**

Create `app/src/main/res/xml/automotive_app.xml`:

```xml
<?xml version="1.0" encoding="utf-8"?>
<automotiveApp>
    <uses name="media"/>
</automotiveApp>
```

**Step 2: Update AndroidManifest.xml**

Replace the `<service>` block and add the `<meta-data>` inside `<application>`:

```xml
<service
    android:name=".service.RadioPlaybackService"
    android:exported="true"
    android:foregroundServiceType="mediaPlayback">
    <intent-filter>
        <action android:name="androidx.media3.session.MediaLibraryService"/>
        <action android:name="android.media.browse.MediaBrowserService"/>
    </intent-filter>
</service>

<meta-data
    android:name="com.google.android.gms.car.application"
    android:resource="@xml/automotive_app" />
```

The service is now `exported="true"` so Android Auto can bind to it. The two intent-filter actions let both Media3 and legacy clients discover it.

**Step 3: Commit**

```bash
git add app/src/main/AndroidManifest.xml app/src/main/res/xml/automotive_app.xml
git commit -m "feat: add Android Auto automotive_app.xml and update service manifest"
```

---

### Task 3: Create RadioPlayerAdapter

This is the thin Player facade. It does NOT produce audio — it only reports state and maps play/stop/pause commands to `RadioController`.

**Files:**
- Create: `app/src/main/java/xyz/cottongin/radio247/service/RadioPlayerAdapter.kt`

**Step 1: Create RadioPlayerAdapter**

Create `app/src/main/java/xyz/cottongin/radio247/service/RadioPlayerAdapter.kt`.

This class implements `androidx.media3.common.Player` by extending `androidx.media3.common.BasePlayer` (which provides default no-op implementations for most methods). We only override what matters for live radio.

Key behaviors:
- Observes `RadioController.state` and translates to Media3 `Player.STATE_*` + `isPlaying`
- `play()` → calls `onPlay` callback (service handles actual play via controller)
- `stop()` → calls `onStop` callback
- `pause()` → calls `onStop` callback (radio can't pause)
- Holds a `MediaMetadata` that gets updated when ICY metadata changes
- Holds a single `MediaItem` representing the current station
- Notifies registered `Player.Listener` instances on state/metadata changes
- `getAvailableCommands()` returns only: `COMMAND_PLAY_PAUSE`, `COMMAND_STOP`, `COMMAND_GET_CURRENT_MEDIA_ITEM`, `COMMAND_GET_MEDIA_ITEMS_METADATA`
- `isCurrentMediaItemLive` returns `true`

Important implementation notes:
- `BasePlayer` requires `seekToDefaultPosition()`, `seekTo(mediaItemIndex, positionMs)`, `getPlaybackParameters()`, `setPlaybackParameters()`, etc. — return defaults / no-ops for all of these.
- Must call `listeners.forEach { it.onXxx() }` when state changes, or use the `invalidateState()` helper if available.

```kotlin
package xyz.cottongin.radio247.service

import android.os.Looper
import androidx.media3.common.BasePlayer
import androidx.media3.common.MediaItem
import androidx.media3.common.MediaMetadata
import androidx.media3.common.PlaybackParameters
import androidx.media3.common.Player
import androidx.media3.common.Timeline
import xyz.cottongin.radio247.audio.IcyMetadata
import xyz.cottongin.radio247.data.model.Station

class RadioPlayerAdapter(
    private val onPlay: () -> Unit,
    private val onStop: () -> Unit,
) : BasePlayer() {

    private val listeners = mutableListOf<Player.Listener>()

    private var _playbackState: Int = Player.STATE_IDLE
    private var _playWhenReady: Boolean = false
    private var _mediaMetadata: MediaMetadata = MediaMetadata.EMPTY
    private var _currentMediaItem: MediaItem? = null

    override fun getApplicationLooper(): Looper = Looper.getMainLooper()

    override fun addListener(listener: Player.Listener) { listeners.add(listener) }
    override fun removeListener(listener: Player.Listener) { listeners.remove(listener) }

    override fun getAvailableCommands(): Player.Commands {
        return Player.Commands.Builder()
            .add(Player.COMMAND_PLAY_PAUSE)
            .add(Player.COMMAND_STOP)
            .add(Player.COMMAND_GET_CURRENT_MEDIA_ITEM)
            .add(Player.COMMAND_GET_MEDIA_ITEMS_METADATA)
            .build()
    }

    override fun getPlaybackState(): Int = _playbackState
    override fun getPlayWhenReady(): Boolean = _playWhenReady
    override fun isPlaying(): Boolean = _playbackState == Player.STATE_READY && _playWhenReady

    override fun getMediaMetadata(): MediaMetadata = _mediaMetadata
    override fun getCurrentMediaItem(): MediaItem? = _currentMediaItem

    override fun play() {
        _playWhenReady = true
        onPlay()
    }

    override fun pause() {
        _playWhenReady = false
        onStop()
    }

    override fun stop() {
        _playWhenReady = false
        onStop()
    }

    override fun prepare() { /* no-op for live radio */ }
    override fun setPlayWhenReady(playWhenReady: Boolean) {
        if (playWhenReady) play() else pause()
    }

    override fun release() {
        listeners.clear()
    }

    override fun getPlaybackParameters(): PlaybackParameters = PlaybackParameters.DEFAULT
    override fun setPlaybackParameters(playbackParameters: PlaybackParameters) { /* no-op */ }

    override fun getRepeatMode(): Int = Player.REPEAT_MODE_OFF
    override fun setRepeatMode(repeatMode: Int) { /* no-op */ }

    override fun getShuffleModeEnabled(): Boolean = false
    override fun setShuffleModeEnabled(shuffleModeEnabled: Boolean) { /* no-op */ }

    override fun seekToDefaultPosition() { /* no-op */ }
    override fun seekToDefaultPosition(mediaItemIndex: Int) { /* no-op */ }
    override fun seekTo(positionMs: Long) { /* no-op */ }
    override fun seekTo(mediaItemIndex: Int, positionMs: Long) { /* no-op */ }

    override fun getCurrentTimeline(): Timeline = Timeline.EMPTY
    override fun getCurrentMediaItemIndex(): Int = 0
    override fun getContentPosition(): Long = 0
    override fun getContentDuration(): Long = -1 // C.TIME_UNSET
    override fun getCurrentPosition(): Long = 0
    override fun getDuration(): Long = -1 // C.TIME_UNSET
    override fun getBufferedPosition(): Long = 0
    override fun getTotalBufferedDuration(): Long = 0
    override fun isCurrentMediaItemLive(): Boolean = true

    // --- State update methods called by RadioPlaybackService ---

    fun updatePlaybackState(state: PlaybackState) {
        val (newPlayerState, newPlayWhenReady) = when (state) {
            is PlaybackState.Idle -> Player.STATE_IDLE to false
            is PlaybackState.Connecting -> Player.STATE_BUFFERING to true
            is PlaybackState.Playing -> Player.STATE_READY to true
            is PlaybackState.Paused -> Player.STATE_READY to false
            is PlaybackState.Reconnecting -> Player.STATE_BUFFERING to true
        }

        val stateChanged = newPlayerState != _playbackState
        val playWhenReadyChanged = newPlayWhenReady != _playWhenReady
        _playbackState = newPlayerState
        _playWhenReady = newPlayWhenReady

        if (stateChanged || playWhenReadyChanged) {
            listeners.forEach { listener ->
                if (playWhenReadyChanged) {
                    listener.onPlayWhenReadyChanged(
                        newPlayWhenReady,
                        Player.PLAY_WHEN_READY_CHANGE_REASON_USER_REQUEST
                    )
                }
                if (stateChanged) {
                    listener.onPlaybackStateChanged(newPlayerState)
                }
                listener.onIsPlayingChanged(isPlaying)
            }
        }
    }

    fun updateStation(station: Station) {
        _currentMediaItem = MediaItem.Builder()
            .setMediaId("station:${station.id}")
            .setMediaMetadata(
                MediaMetadata.Builder()
                    .setTitle(station.name)
                    .setIsPlayable(true)
                    .build()
            )
            .build()
        listeners.forEach { it.onMediaItemTransition(_currentMediaItem, Player.MEDIA_ITEM_TRANSITION_REASON_PLAYLIST_CHANGED) }
    }

    fun updateMetadata(station: Station, metadata: IcyMetadata?, artworkUri: android.net.Uri? = null) {
        _mediaMetadata = MediaMetadata.Builder()
            .setStation(station.name)
            .setTitle(metadata?.title ?: station.name)
            .setArtist(metadata?.artist)
            .setArtworkUri(artworkUri)
            .setIsPlayable(true)
            .build()
        listeners.forEach { it.onMediaMetadataChanged(_mediaMetadata) }
    }
}
```

**Step 2: Verify it compiles**

Run: `./gradlew :app:compileDebugKotlin 2>&1 | tail -20`

Expected: Still fails on `RadioPlaybackService` and `NotificationHelper` (they still use old APIs). But `RadioPlayerAdapter.kt` itself should have no errors. If there are `BasePlayer` abstract method errors, add the missing no-op overrides.

**Step 3: Commit**

```bash
git add app/src/main/java/xyz/cottongin/radio247/service/RadioPlayerAdapter.kt
git commit -m "feat: add RadioPlayerAdapter — thin Player facade for Media3"
```

---

### Task 4: Rewrite RadioPlaybackService

This is the largest task. Convert from `LifecycleService` + manual notifications to `MediaLibraryService` with `MediaLibrarySession`.

**Files:**
- Modify: `app/src/main/java/xyz/cottongin/radio247/service/RadioPlaybackService.kt`

**Step 1: Change the class signature and imports**

Replace the superclass and imports. The service now extends `MediaLibraryService()`.

Remove all imports of:
- `android.support.v4.media.session.MediaSessionCompat`
- `androidx.lifecycle.LifecycleService`

Add imports for:
- `androidx.media3.session.MediaLibraryService`
- `androidx.media3.session.MediaLibraryService.MediaLibrarySession`
- `androidx.media3.session.MediaSession`
- `androidx.media3.session.SessionCommand`
- `androidx.media3.session.SessionResult`
- `androidx.media3.session.CommandButton`
- `androidx.media3.common.MediaItem`
- `androidx.media3.common.MediaMetadata`
- `android.os.Bundle`
- `com.google.common.util.concurrent.Futures`
- `com.google.common.util.concurrent.ListenableFuture`

Change class declaration:

```kotlin
class RadioPlaybackService : MediaLibraryService() {
```

**Step 2: Replace mediaSession and notificationHelper fields**

Remove:
- `private val notificationHelper = NotificationHelper(this)` 
- `private var mediaSession: MediaSessionCompat? = null`

Add:
- `private var mediaSession: MediaLibrarySession? = null`
- `private var playerAdapter: RadioPlayerAdapter? = null`
- `private val seekToLiveCommand = SessionCommand("SEEK_TO_LIVE", Bundle.EMPTY)`

**Step 3: Implement onGetSession()**

This is required by `MediaLibraryService`:

```kotlin
override fun onGetSession(controllerInfo: MediaSession.ControllerInfo): MediaLibrarySession? {
    return mediaSession
}
```

**Step 4: Rewrite ensureMediaSession()**

Replace the old `ensureMediaSession()` that created a `MediaSessionCompat` with one that creates a `MediaLibrarySession`:

```kotlin
private fun ensureMediaSession() {
    if (mediaSession != null) return

    val adapter = RadioPlayerAdapter(
        onPlay = {
            val state = controller.state.value
            val station = when (state) {
                is PlaybackState.Playing -> state.station
                is PlaybackState.Paused -> state.station
                is PlaybackState.Connecting -> state.station
                is PlaybackState.Reconnecting -> state.station
                is PlaybackState.Idle -> null
            }
            station?.let { controller.play(it) }
        },
        onStop = { controller.stop() }
    )
    playerAdapter = adapter

    val sessionActivityIntent = packageManager
        .getLaunchIntentForPackage(packageName)
        ?.let { intent ->
            PendingIntent.getActivity(
                this, 0, intent,
                PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE
            )
        }

    val seekToLiveButton = CommandButton.Builder(CommandButton.ICON_SKIP_FORWARD)
        .setDisplayName("Live")
        .setSessionCommand(seekToLiveCommand)
        .build()

    mediaSession = MediaLibrarySession.Builder(this, adapter, LibrarySessionCallback())
        .setSessionActivity(sessionActivityIntent!!)
        .setCustomLayout(listOf(seekToLiveButton))
        .build()
}
```

**Step 5: Implement LibrarySessionCallback**

This inner class handles the Android Auto browse tree and custom commands:

```kotlin
private inner class LibrarySessionCallback : MediaLibrarySession.Callback {

    override fun onGetLibraryRoot(
        session: MediaLibrarySession,
        browser: MediaSession.ControllerInfo,
        params: LibraryParams?
    ): ListenableFuture<LibraryResult<MediaItem>> {
        val root = MediaItem.Builder()
            .setMediaId("root")
            .setMediaMetadata(
                MediaMetadata.Builder()
                    .setIsBrowsable(true)
                    .setIsPlayable(false)
                    .setMediaType(MediaMetadata.MEDIA_TYPE_FOLDER_MIXED)
                    .build()
            )
            .build()
        return Futures.immediateFuture(LibraryResult.ofItem(root, params))
    }

    override fun onGetChildren(
        session: MediaLibrarySession,
        browser: MediaSession.ControllerInfo,
        parentId: String,
        page: Int,
        pageSize: Int,
        params: LibraryParams?
    ): ListenableFuture<LibraryResult<ImmutableList<MediaItem>>> {
        val deferred = serviceScope.launch(Dispatchers.IO) {
            // resolved in the coroutine below
        }
        // Use a settable future since we need coroutines
        val future = androidx.concurrent.futures.ResolvableFuture.create<LibraryResult<ImmutableList<MediaItem>>>()
        serviceScope.launch {
            try {
                val items = when {
                    parentId == "root" -> buildRootChildren()
                    parentId == "unsorted" -> buildUnsortedStations()
                    parentId.startsWith("playlist:") -> {
                        val playlistId = parentId.removePrefix("playlist:").toLong()
                        buildPlaylistStations(playlistId)
                    }
                    else -> emptyList()
                }
                future.set(LibraryResult.ofItemList(items, params))
            } catch (e: Exception) {
                future.set(LibraryResult.ofError(LibraryResult.RESULT_ERROR_UNKNOWN))
            }
        }
        return future
    }

    override fun onCustomCommand(
        session: MediaSession,
        controller: MediaSession.ControllerInfo,
        customCommand: SessionCommand,
        args: Bundle
    ): ListenableFuture<SessionResult> {
        if (customCommand.customAction == "SEEK_TO_LIVE") {
            handleSeekLive()
            return Futures.immediateFuture(SessionResult(SessionResult.RESULT_SUCCESS))
        }
        return super.onCustomCommand(session, controller, customCommand, args)
    }

    override fun onConnect(
        session: MediaSession,
        controller: MediaSession.ControllerInfo
    ): MediaSession.ConnectionResult {
        val sessionCommands = MediaSession.ConnectionResult.DEFAULT_SESSION_AND_LIBRARY_COMMANDS
            .buildUpon()
            .add(seekToLiveCommand)
            .build()
        return MediaSession.ConnectionResult.AcceptedResultBuilder(session)
            .setAvailableSessionCommands(sessionCommands)
            .build()
    }

    override fun onAddMediaItems(
        mediaSession: MediaSession,
        controller: MediaSession.ControllerInfo,
        mediaItems: MutableList<MediaItem>
    ): ListenableFuture<List<MediaItem>> {
        // When a station is selected in Android Auto, start playback
        val item = mediaItems.firstOrNull() ?: return Futures.immediateFuture(emptyList())
        val mediaId = item.mediaId
        if (mediaId.startsWith("station:")) {
            val stationId = mediaId.removePrefix("station:").toLongOrNull()
            if (stationId != null) {
                serviceScope.launch {
                    val station = stationDao.getStationById(stationId)
                    station?.let { this@RadioPlaybackService.controller.play(it) }
                }
            }
        }
        return Futures.immediateFuture(mediaItems)
    }
}
```

**Step 6: Add browse tree helper methods**

```kotlin
private suspend fun buildRootChildren(): List<MediaItem> {
    val items = mutableListOf<MediaItem>()
    val playlists = database.playlistDao().getAllPlaylists().first()
    for (playlist in playlists) {
        items.add(
            MediaItem.Builder()
                .setMediaId("playlist:${playlist.id}")
                .setMediaMetadata(
                    MediaMetadata.Builder()
                        .setTitle(playlist.name)
                        .setIsBrowsable(true)
                        .setIsPlayable(false)
                        .setMediaType(MediaMetadata.MEDIA_TYPE_FOLDER_PLAYLISTS)
                        .build()
                )
                .build()
        )
    }
    val unsorted = stationDao.getUnsortedStations().first()
    if (unsorted.isNotEmpty()) {
        items.add(
            MediaItem.Builder()
                .setMediaId("unsorted")
                .setMediaMetadata(
                    MediaMetadata.Builder()
                        .setTitle("Unsorted")
                        .setIsBrowsable(true)
                        .setIsPlayable(false)
                        .setMediaType(MediaMetadata.MEDIA_TYPE_FOLDER_PLAYLISTS)
                        .build()
                )
                .build()
        )
    }
    return items
}

private suspend fun buildPlaylistStations(playlistId: Long): List<MediaItem> {
    return stationDao.getStationsByPlaylist(playlistId).first().map { it.toMediaItem() }
}

private suspend fun buildUnsortedStations(): List<MediaItem> {
    return stationDao.getUnsortedStations().first().map { it.toMediaItem() }
}

private fun Station.toMediaItem(): MediaItem {
    return MediaItem.Builder()
        .setMediaId("station:${id}")
        .setMediaMetadata(
            MediaMetadata.Builder()
                .setTitle(name)
                .setArtworkUri(defaultArtworkUrl?.let { android.net.Uri.parse(it) })
                .setIsPlayable(true)
                .setIsBrowsable(false)
                .setMediaType(MediaMetadata.MEDIA_TYPE_MUSIC)
                .build()
        )
        .build()
}
```

**Step 7: Remove manual notification methods**

Delete these methods entirely:
- `startForegroundWithPlaceholder()` — Media3 handles foreground
- `updateNotification()` — Media3 auto-generates from session state

Replace all calls to `updateNotification(station, metadata, isReconnecting)` with calls to update the player adapter's state/metadata instead:

```kotlin
// Where you previously called: updateNotification(station, null, isReconnecting = false)
// Now call:
playerAdapter?.updateStation(station)
playerAdapter?.updatePlaybackState(controller.state.value)
```

When ICY metadata arrives:
```kotlin
// Where you previously called: updateNotification(station, event.metadata, false)
// Now call:
playerAdapter?.updateMetadata(station, event.metadata)
```

**Step 8: Update startForeground call at the start of playback**

The initial `startForegroundWithPlaceholder(station)` call needs to be replaced. `MediaLibraryService` manages foreground state, but we still need to ensure the adapter and session exist before the service tries to go foreground:

```kotlin
// In handlePlay(), replace startForegroundWithPlaceholder(station) with:
ensureMediaSession()
playerAdapter?.updateStation(station)
playerAdapter?.updatePlaybackState(PlaybackState.Connecting(station))
```

**Step 9: Remove onBind returning null**

Delete the `onBind` override — `MediaLibraryService` provides its own binding. Also remove the `super.onStartCommand()` call if present (it was needed for `LifecycleService` but not `MediaLibraryService`).

**Step 10: Update cleanupResources()**

Replace `mediaSession?.release()` with:
```kotlin
mediaSession?.release()
mediaSession = null
playerAdapter?.release()
playerAdapter = null
```

**Step 11: Update handlePlay finally block**

In the `finally` block of `handlePlay()`, when transitioning to `Idle`, update the adapter:
```kotlin
playerAdapter?.updatePlaybackState(PlaybackState.Idle)
```

And remove the `stopForeground(Service.STOP_FOREGROUND_REMOVE)` call — `MediaLibraryService` handles this.

**Step 12: Update onCreate — remove notificationHelper.createChannel()**

`MediaLibraryService` with the default notification provider manages its own channel. Remove the `notificationHelper.createChannel()` call from `onCreate()`.

**Step 13: Album art on metadata change**

In `awaitEngine()`, when `AudioEngineEvent.MetadataChanged` fires, resolve artwork and pass it to the adapter:

```kotlin
is AudioEngineEvent.MetadataChanged -> {
    currentMetadata = event.metadata
    val playingState = controller.state.value
    if (playingState is PlaybackState.Playing) {
        transition(playingState.copy(metadata = event.metadata))
    }
    persistMetadataSnapshot(station.id, event.metadata)
    // Resolve artwork and update adapter
    serviceScope.launch {
        val artUrl = app.albumArtResolver.resolve(
            artist = event.metadata.artist,
            title = event.metadata.title,
            icyStreamUrl = event.metadata.streamUrl,
            stationArtworkUrl = station.defaultArtworkUrl
        )
        val artUri = artUrl?.let { android.net.Uri.parse(it) }
        playerAdapter?.updateMetadata(station, event.metadata, artUri)
    }
}
```

**Step 14: Verify build**

Run: `./gradlew :app:compileDebugKotlin 2>&1 | tail -40`

Expected: Should compile (NotificationHelper still exists but is unused). Fix any compilation errors — common issues will be missing imports or `BasePlayer` abstract methods needing overrides.

**Step 15: Commit**

```bash
git add app/src/main/java/xyz/cottongin/radio247/service/RadioPlaybackService.kt
git commit -m "feat: rewrite RadioPlaybackService as MediaLibraryService with browse tree"
```

---

### Task 5: Delete NotificationHelper

**Files:**
- Delete: `app/src/main/java/xyz/cottongin/radio247/service/NotificationHelper.kt`

**Step 1: Delete the file**

Remove `NotificationHelper.kt`. It's fully replaced by Media3's automatic notification management.

**Step 2: Verify no remaining references**

Search for `NotificationHelper` in the codebase. It should only appear in import cleanup.

Run: `rg "NotificationHelper" --type kotlin`

Expected: Zero results.

**Step 3: Verify build**

Run: `./gradlew :app:compileDebugKotlin 2>&1 | tail -20`

Expected: Clean compilation.

**Step 4: Commit**

```bash
git add -A
git commit -m "refactor: remove NotificationHelper — Media3 handles notifications"
```

---

### Task 6: Update RadioController (if needed)

**Files:**
- Modify: `app/src/main/java/xyz/cottongin/radio247/service/RadioController.kt`

**Step 1: Check if RadioController needs changes**

`RadioController.play()` calls `application.startForegroundService(intent)`. With `MediaLibraryService`, the service is typically started via binding (Android Auto / MediaController) or via `startForegroundService` (from the app's UI). The current intent-based approach should still work because `MediaLibraryService` extends `Service` and `onStartCommand` still gets called.

Verify that `RadioController` still compiles and functions — the intent actions (`ACTION_PLAY`, `ACTION_STOP`, etc.) are still handled by `onStartCommand` in the rewritten service.

If `startForegroundService` causes issues (Media3 expects to manage foreground state), switch to `startService` for non-play actions and keep `startForegroundService` for play:

```kotlin
// In stop(), pause(), seekToLive() — use startService instead of startForegroundService
application.startService(intent)
```

This is already the case in the current code, so no changes should be needed.

**Step 2: Commit (only if changes were made)**

```bash
git add app/src/main/java/xyz/cottongin/radio247/service/RadioController.kt
git commit -m "refactor: adjust RadioController for MediaLibraryService compatibility"
```

---

### Task 7: Full Build + Smoke Test

**Files:** None (verification only)

**Step 1: Clean build**

Run: `./gradlew clean :app:assembleDebug 2>&1 | tail -30`

Expected: BUILD SUCCESSFUL

**Step 2: Run existing tests**

Run: `./gradlew :app:testDebugUnitTest 2>&1 | tail -30`

Expected: All existing tests pass. If any tests reference `NotificationHelper` or `MediaSessionCompat`, update them.

**Step 3: Install and manual test**

If a device/emulator is connected:

Run: `./gradlew :app:installDebug`

Manual verification checklist:
- [ ] App launches
- [ ] Selecting a station starts playback
- [ ] System notification appears with station name + track info
- [ ] Album art appears in notification (when resolved)
- [ ] Play/Stop button works in notification
- [ ] "Live" custom button appears in notification
- [ ] Lockscreen shows media controls
- [ ] Stopping playback dismisses notification

Android Auto verification (requires Android Auto Desktop Head Unit or car):
- [ ] App appears in Android Auto media app list
- [ ] Browsing shows playlists
- [ ] Tapping a playlist shows stations
- [ ] Tapping a station starts playback
- [ ] Now Playing screen shows station name + metadata

**Step 4: Final commit if any fixes were needed**

```bash
git add -A
git commit -m "fix: address build/test issues from Media3 migration"
```

---

### Task 8: Notification Channel Cleanup

**Files:**
- Modify: `app/src/main/java/xyz/cottongin/radio247/service/RadioPlaybackService.kt` (if needed)

**Step 1: Verify notification channel**

Media3's `DefaultMediaNotificationProvider` creates its own notification channel. The old `"radio_playback"` channel from `NotificationHelper` may linger on devices that had the old version installed. This is cosmetic — Android handles orphaned channels gracefully.

If you want to customize the channel name/importance, override `MediaLibraryService.onUpdateNotification()` or provide a custom `MediaNotification.Provider`. For now, the default is fine (importance defaults to LOW for media sessions).

**Step 2: Commit (only if changes)**

No commit needed unless customization was added.

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## Summary of New/Changed/Deleted Files

| File | Action |
|---|---|
| `gradle/libs.versions.toml` | Modified — add media3, remove old media |
| `app/build.gradle.kts` | Modified — swap deps |
| `app/src/main/AndroidManifest.xml` | Modified — exported service + Auto meta-data |
| `app/src/main/res/xml/automotive_app.xml` | Created |
| `app/src/main/java/.../service/RadioPlayerAdapter.kt` | Created |
| `app/src/main/java/.../service/RadioPlaybackService.kt` | Major rewrite |
| `app/src/main/java/.../service/NotificationHelper.kt` | Deleted |
| `app/src/main/java/.../service/RadioController.kt` | Possibly minor tweaks |