chore: format code

app/src/main/kotlin/ca/ksamad/encore/EncoreApplication.kt

@@ -8,15 +8,13 @@ import coil3.PlatformContext
 import coil3.SingletonImageLoader
 
 /**
- * Holds the app-scoped [MpdConnectionManager] so the MPD connection outlives any
+ * Holds the app-scoped [MpdConnectionManager] so the MPD connection outlives any single Activity
- * single Activity and can be shared with the foreground
+ * and can be shared with the foreground [ca.ksamad.encore.playback.PlaybackService].
- * [ca.ksamad.encore.playback.PlaybackService].
  *
- * Also the Coil [SingletonImageLoader.Factory], wiring cover-art loading to that
+ * Also the Coil [SingletonImageLoader.Factory], wiring cover-art loading to that same manager so
- * same manager so `AsyncImage` calls anywhere in the app fetch (and cache) MPD art.
+ * `AsyncImage` calls anywhere in the app fetch (and cache) MPD art.
  */
 class EncoreApplication : Application(), SingletonImageLoader.Factory {
-
     val manager: MpdConnectionManager by lazy { MpdConnectionManager(this) }
 
     override fun onCreate() {

app/src/main/kotlin/ca/ksamad/encore/MainActivity.kt

@@ -20,7 +20,6 @@ import ca.ksamad.encore.playback.VolumeKeyDispatcher
 import ca.ksamad.encore.ui.EncoreApp
 
 class MainActivity : ComponentActivity() {
-
     private val requestNotificationPermission =
         registerForActivityResult(ActivityResultContracts.RequestPermission()) { /* best-effort */ }
 
@@ -38,9 +37,7 @@ class MainActivity : ComponentActivity() {
             EncoreTheme {
                 Scaffold(modifier = Modifier.fillMaxSize()) { innerPadding ->
                     Surface(
-                        modifier = Modifier
+                        modifier = Modifier.fillMaxSize().padding(innerPadding),
-                            .fillMaxSize()
-                            .padding(innerPadding),
                         color = MaterialTheme.colorScheme.background,
                     ) {
                         EncoreApp()
@@ -58,7 +55,8 @@ class MainActivity : ComponentActivity() {
     // now-playing notification / QS controls won't show.
     private fun maybeRequestNotificationPermission() {
         if (Build.VERSION.SDK_INT < Build.VERSION_CODES.TIRAMISU) return
-        val granted = ContextCompat.checkSelfPermission(this, Manifest.permission.POST_NOTIFICATIONS) ==
+        val granted =
+            ContextCompat.checkSelfPermission(this, Manifest.permission.POST_NOTIFICATIONS) ==
                 PackageManager.PERMISSION_GRANTED
         if (!granted) requestNotificationPermission.launch(Manifest.permission.POST_NOTIFICATIONS)
     }

app/src/main/kotlin/ca/ksamad/encore/Theme.kt

@@ -13,8 +13,8 @@ import androidx.compose.ui.platform.LocalContext
 /**
  * Material 3 theme for the app.
  *
- * On Android 12+ it uses "dynamic color" (the palette derived from the user's
+ * On Android 12+ it uses "dynamic color" (the palette derived from the user's wallpaper); on older
- * wallpaper); on older versions it falls back to a default light/dark scheme.
+ * versions it falls back to a default light/dark scheme.
  */
 @Composable
 fun EncoreTheme(
@@ -22,14 +22,20 @@ fun EncoreTheme(
     dynamicColor: Boolean = true,
     content: @Composable () -> Unit,
 ) {
-    val colorScheme = when {
+    val colorScheme =
+        when {
             dynamicColor && Build.VERSION.SDK_INT >= Build.VERSION_CODES.S -> {
                 val context = LocalContext.current
                 if (darkTheme) dynamicDarkColorScheme(context) else dynamicLightColorScheme(context)
             }
 
-        darkTheme -> darkColorScheme()
+            darkTheme -> {
-        else -> lightColorScheme()
+                darkColorScheme()
+            }
+
+            else -> {
+                lightColorScheme()
+            }
         }
 
     MaterialTheme(

app/src/main/kotlin/ca/ksamad/encore/data/SettingsRepository.kt

@@ -13,31 +13,35 @@ import kotlinx.coroutines.flow.map
 // A single process-wide DataStore instance, tied to the application context via
 // this property delegate (the recommended pattern — creating more than one
 // DataStore for the same file throws).
-private val Context.dataStore: DataStore<Preferences> by preferencesDataStore(name = "connection_settings")
+private val Context.dataStore: DataStore<Preferences> by
+    preferencesDataStore(name = "connection_settings")
 
 /**
- * Reads and writes the persisted [ConnectionSettings] using Preferences
+ * Reads and writes the persisted [ConnectionSettings] using Preferences DataStore. Reads come back
- * DataStore. Reads come back as a [Flow] that emits on every change; the write
+ * as a [Flow] that emits on every change; the write is a `suspend` transaction.
- * is a `suspend` transaction.
  */
 class SettingsRepository(private val context: Context) {
-
     private object Keys {
         val HOST = stringPreferencesKey("host")
         val PORT = intPreferencesKey("port")
     }
 
     /**
-     * The saved settings, or `null` if the user has never connected (no host
+     * The saved settings, or `null` if the user has never connected (no host persisted yet).
-     * persisted yet). Callers use the null case to show first-run UI / decide
+     * Callers use the null case to show first-run UI / decide whether to auto-connect.
-     * whether to auto-connect.
      */
-    val settingsOrNull: Flow<ConnectionSettings?> = context.dataStore.data.map { prefs ->
+    val settingsOrNull: Flow<ConnectionSettings?> =
+        context.dataStore.data.map { prefs ->
             val host = prefs[Keys.HOST] ?: return@map null
-        ConnectionSettings(host = host, port = prefs[Keys.PORT] ?: ConnectionSettings.DEFAULT.port)
+            ConnectionSettings(
+                host = host,
+                port = prefs[Keys.PORT] ?: ConnectionSettings.DEFAULT.port,
+            )
         }
 
-    /** Same as [settingsOrNull] but falling back to [ConnectionSettings.DEFAULT] for form prefill. */
+    /**
+     * Same as [settingsOrNull] but falling back to [ConnectionSettings.DEFAULT] for form prefill.
+     */
     val settings: Flow<ConnectionSettings> = settingsOrNull.map { it ?: ConnectionSettings.DEFAULT }
 
     suspend fun save(settings: ConnectionSettings) {

app/src/main/kotlin/ca/ksamad/encore/mpd/MpdClient.kt

@@ -5,6 +5,7 @@ import ca.ksamad.encore.mpd.model.MpdSong
 import ca.ksamad.encore.mpd.model.MpdStatistics
 import ca.ksamad.encore.mpd.model.MpdStatus
 import ca.ksamad.encore.mpd.model.PlayerState
+import java.io.IOException
 import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
@@ -22,32 +23,31 @@ import kotlinx.coroutines.sync.Semaphore
 import kotlinx.coroutines.sync.withLock
 import kotlinx.coroutines.sync.withPermit
 import kotlinx.coroutines.withContext
-import java.io.IOException
 
 /**
- * The high-level, coroutine-driven MPD client. It owns **two** connections, the
+ * The high-level, coroutine-driven MPD client. It owns **two** connections, the pattern MALP and
- * pattern MALP and other real clients use:
+ * other real clients use:
  *
- *  - a **command** connection, guarded by a [Mutex], for request/response
+ * - a **command** connection, guarded by a [Mutex], for request/response commands (play, setvol,
- *    commands (play, setvol, playlistinfo, …);
+ *   playlistinfo, …);
- *  - an **idle** connection parked in the blocking `idle` command, so the server
+ * - an **idle** connection parked in the blocking `idle` command, so the server can push change
- *    can push change notifications. Each `changed:` event triggers a refresh on
+ *   notifications. Each `changed:` event triggers a refresh on the command connection, which flows
- *    the command connection, which flows out through [status]/[currentSong].
+ *   out through [status]/[currentSong].
  *
  * **Resilience.** A quiet command connection would otherwise be reaped by MPD's
- * `connection_timeout`, so a periodic [keepalive] `ping` keeps it warm and
+ * `connection_timeout`, so a periodic [keepalive] `ping` keeps it warm and detects death early. Any
- * detects death early. Any transport failure triggers a transparent
+ * transport failure triggers a transparent [reconnect][triggerReconnect] (staying on the player,
- * [reconnect][triggerReconnect] (staying on the player, not bouncing the user to
+ * not bouncing the user to the connect screen); only repeated failures surface as
- * the connect screen); only repeated failures surface as
+ * [MpdConnectionState.Error]. Server-side `ACK` errors are *not* treated as connection failures.
- * [MpdConnectionState.Error]. Server-side `ACK` errors are *not* treated as
- * connection failures.
  *
  * A [connectionFactory] is injectable so tests can supply fake transports.
  */
 class MpdClient(
     private val ioDispatcher: CoroutineDispatcher = Dispatchers.IO,
     private val connectionFactory: (host: String, port: Int, readTimeoutMs: Int) -> MpdConnection =
-        { host, port, readTimeoutMs -> MpdConnection.connect(host, port, readTimeoutMs = readTimeoutMs) },
+        { host, port, readTimeoutMs ->
+            MpdConnection.connect(host, port, readTimeoutMs = readTimeoutMs)
+        },
 ) {
     private val scope = CoroutineScope(SupervisorJob() + ioDispatcher)
 
@@ -64,10 +64,10 @@ class MpdClient(
     private var password: String? = null
 
     /** True while an intentional [disconnect]/[shutdown] is in progress. */
-    @Volatile
+    @Volatile private var shuttingDown = false
-    private var shuttingDown = false
 
-    private val _connectionState = MutableStateFlow<MpdConnectionState>(MpdConnectionState.Disconnected)
+    private val _connectionState =
+        MutableStateFlow<MpdConnectionState>(MpdConnectionState.Disconnected)
     val connectionState = _connectionState.asStateFlow()
 
     private val _status = MutableStateFlow<MpdStatus?>(null)
@@ -79,11 +79,14 @@ class MpdClient(
     // --- Lifecycle ----------------------------------------------------------
 
     /**
-     * Open both connections, authenticate, prime the initial state, and start
+     * Open both connections, authenticate, prime the initial state, and start the idle + keepalive
-     * the idle + keepalive loops. On failure the state becomes
+     * loops. On failure the state becomes [MpdConnectionState.Error] and the call throws.
-     * [MpdConnectionState.Error] and the call throws.
      */
-    suspend fun connect(host: String, port: Int = MpdConnection.DEFAULT_PORT, password: String? = null) {
+    suspend fun connect(
+        host: String,
+        port: Int = MpdConnection.DEFAULT_PORT,
+        password: String? = null,
+    ) {
         disconnect() // ensure a clean slate if re-connecting
         shuttingDown = false
         this.host = host
@@ -159,31 +162,40 @@ class MpdClient(
     // loop, keeping us in lockstep with the server (and other clients).
 
     suspend fun play() = run(MpdCommands.play())
+
     suspend fun playPos(pos: Int) = run(MpdCommands.playPos(pos))
+
     suspend fun playId(songId: Int) = run(MpdCommands.playId(songId))
+
     suspend fun stop() = run(MpdCommands.stop())
+
     suspend fun clearQueue() = run(MpdCommands.clear())
 
     /** Remove a queue entry by its stable song id. */
     suspend fun removeQueueItem(songId: Int) = run(MpdCommands.deleteId(songId))
 
     /** Insert a single track at an absolute queue position (used to undo a removal). */
-    suspend fun addTrackAt(uri: String, position: Int) = run(MpdCommands.add(uri, position.toString()))
+    suspend fun addTrackAt(
+        uri: String,
+        position: Int,
+    ) = run(MpdCommands.add(uri, position.toString()))
 
     /** Append a single track to the end of the queue; playback is untouched. */
     suspend fun queueTrack(uri: String) = run(MpdCommands.add(uri))
 
     /**
-     * Insert a single track right after the current one so it plays next. Falls
+     * Insert a single track right after the current one so it plays next. Falls back to a plain
-     * back to a plain append when nothing is playing — no current song to anchor
+     * append when nothing is playing — no current song to anchor the relative `"+0"` position to.
-     * the relative `"+0"` position to.
      */
     suspend fun playTrackNext(uri: String) = withCommand { conn ->
         val playing = MpdStatus.from(conn.execute(MpdCommands.status()).toMap()).song != null
         conn.execute(MpdCommands.add(uri, position = if (playing) "+0" else null))
     }
+
     suspend fun next() = run(MpdCommands.next())
+
     suspend fun previous() = run(MpdCommands.previous())
+
     suspend fun pause(paused: Boolean) = run(MpdCommands.pause(paused))
 
     /** Flip play/pause based on the latest known [status]. */
@@ -193,10 +205,15 @@ class MpdClient(
     }
 
     suspend fun seekCurrent(seconds: Double) = run(MpdCommands.seekCurrent(seconds))
+
     suspend fun setVolume(volume: Int) = run(MpdCommands.setVolume(volume))
+
     suspend fun setRepeat(on: Boolean) = run(MpdCommands.repeat(on))
+
     suspend fun setRandom(on: Boolean) = run(MpdCommands.random(on))
+
     suspend fun setSingle(on: Boolean) = run(MpdCommands.single(on))
+
     suspend fun setConsume(on: Boolean) = run(MpdCommands.consume(on))
 
     /** Fetch the current play queue. */
@@ -215,31 +232,47 @@ class MpdClient(
     }
 
     /** Replace the queue with an album and start playing it. */
-    suspend fun playAlbum(album: String, albumArtist: String?) = withCommand { conn ->
+    suspend fun playAlbum(
+        album: String,
+        albumArtist: String?,
+    ) = withCommand { conn ->
         conn.execute(MpdCommands.clear())
         conn.execute(MpdCommands.findAddAlbum(album, albumArtist))
         conn.execute(MpdCommands.play())
     }
 
     /** Append an album's tracks to the end of the queue; playback is untouched. */
-    suspend fun queueAlbum(album: String, albumArtist: String?) = withCommand { conn ->
+    suspend fun queueAlbum(
+        album: String,
+        albumArtist: String?,
+    ) = withCommand { conn ->
         conn.execute(MpdCommands.findAddAlbum(album, albumArtist))
     }
 
     /**
-     * Insert an album right after the current track so it plays next. Falls back
+     * Insert an album right after the current track so it plays next. Falls back to a plain append
-     * to a plain append when nothing is playing — there is no current song for the
+     * when nothing is playing — there is no current song for the relative `"+0"` position to anchor
-     * relative `"+0"` position to anchor to.
+     * to.
      */
-    suspend fun playAlbumNext(album: String, albumArtist: String?) = withCommand { conn ->
+    suspend fun playAlbumNext(
+        album: String,
+        albumArtist: String?,
+    ) = withCommand { conn ->
         val playing = MpdStatus.from(conn.execute(MpdCommands.status()).toMap()).song != null
-        conn.execute(MpdCommands.findAddAlbum(album, albumArtist, position = if (playing) "+0" else null))
+        conn.execute(
+            MpdCommands.findAddAlbum(album, albumArtist, position = if (playing) "+0" else null)
+        )
     }
 
     /** Every track of an album, ordered by disc then track number. */
-    suspend fun albumTracks(album: String, albumArtist: String?): List<MpdSong> = withCommand { conn ->
+    suspend fun albumTracks(
-        conn.execute(MpdCommands.findAlbumTracks(album, albumArtist))
+        album: String,
-            .split().mapNotNull { MpdSong.from(it) }
+        albumArtist: String?,
+    ): List<MpdSong> = withCommand { conn ->
+        conn
+            .execute(MpdCommands.findAlbumTracks(album, albumArtist))
+            .split()
+            .mapNotNull { MpdSong.from(it) }
             .sortedWith(compareBy({ it.disc.leadingInt() }, { it.track.leadingInt() }))
     }
 
@@ -247,25 +280,40 @@ class MpdClient(
     suspend fun songArt(uri: String): ByteArray? = withArtConnection { conn -> readArt(conn, uri) }
 
     /** Cover art bytes for an album (resolves a representative track first). */
-    suspend fun albumArt(album: String, albumArtist: String?): ByteArray? = withArtConnection { conn ->
+    suspend fun albumArt(
-        val trackUri = conn.execute(MpdCommands.findFirstTrack(album, albumArtist))
+        album: String,
-            .split().firstOrNull()?.get("file")
+        albumArtist: String?,
-            ?: return@withArtConnection null
+    ): ByteArray? = withArtConnection { conn ->
+        val trackUri =
+            conn
+                .execute(MpdCommands.findFirstTrack(album, albumArtist))
+                .split()
+                .firstOrNull()
+                ?.get("file") ?: return@withArtConnection null
         readArt(conn, trackUri)
     }
 
     /** Try folder cover (`albumart`), then embedded art (`readpicture`). */
-    private fun readArt(conn: MpdConnection, uri: String): ByteArray? =
+    private fun readArt(
+        conn: MpdConnection,
+        uri: String,
+    ): ByteArray? =
         readArtChunks(conn, embedded = false, uri) ?: readArtChunks(conn, embedded = true, uri)
 
     /** Loop the chunked art protocol until the whole image (per `size:`) is read. */
-    private fun readArtChunks(conn: MpdConnection, embedded: Boolean, uri: String): ByteArray? {
+    private fun readArtChunks(
+        conn: MpdConnection,
+        embedded: Boolean,
+        uri: String,
+    ): ByteArray? {
         val out = java.io.ByteArrayOutputStream()
         var offset = 0
         while (true) {
-            val resp = try {
+            val resp =
+                try {
                     conn.execute(
-                    if (embedded) MpdCommands.readPicture(uri, offset) else MpdCommands.albumArt(uri, offset),
+                        if (embedded) MpdCommands.readPicture(uri, offset)
+                        else MpdCommands.albumArt(uri, offset)
                     )
                 } catch (e: MpdAckException) {
                     return null // no such art
@@ -287,8 +335,8 @@ class MpdClient(
     }
 
     /**
-     * Serialize access to the command connection. A server `ACK` is rethrown as-is
+     * Serialize access to the command connection. A server `ACK` is rethrown as-is (the connection
-     * (the connection is fine); a transport failure triggers a reconnect.
+     * is fine); a transport failure triggers a reconnect.
      */
     private suspend fun <T> withCommand(block: (MpdConnection) -> T): T =
         withContext(ioDispatcher) {
@@ -334,7 +382,10 @@ class MpdClient(
         }
 
     private suspend fun borrowArtConnection(): MpdConnection {
-        synchronized(artPoolLock) { idleArtConnections.removeFirstOrNull() }?.let { return it }
+        synchronized(artPoolLock) { idleArtConnections.removeFirstOrNull() }
+            ?.let {
+                return it
+            }
         return withContext(ioDispatcher) {
             val h = host ?: throw MpdConnectionException("not connected")
             val conn = connectionFactory(h, port, COMMAND_READ_TIMEOUT_MS)
@@ -345,7 +396,8 @@ class MpdClient(
     }
 
     private fun returnArtConnection(conn: MpdConnection) {
-        val kept = synchronized(artPoolLock) {
+        val kept =
+            synchronized(artPoolLock) {
                 if (idleArtConnections.size < ART_POOL_SIZE) {
                     idleArtConnections.addLast(conn)
                     true
@@ -358,7 +410,8 @@ class MpdClient(
 
     /** Close and drop all pooled art connections (on disconnect/reconnect/teardown). */
     private fun closeArtConnections() {
-        val toClose = synchronized(artPoolLock) {
+        val toClose =
+            synchronized(artPoolLock) {
                 val copy = idleArtConnections.toList()
                 idleArtConnections.clear()
                 copy
@@ -368,8 +421,10 @@ class MpdClient(
 
     /** Re-read `status` and `currentsong` into the flows (single round-trip). */
     private suspend fun refresh() {
-        val (status, song) = withCommand { conn ->
+        val (status, song) =
-            val (statusResp, songResp) = conn.executeList(
+            withCommand { conn ->
+                val (statusResp, songResp) =
+                    conn.executeList(
                         MpdCommands.status(),
                         MpdCommands.currentSong(),
                     )
@@ -384,7 +439,8 @@ class MpdClient(
         idleJob = scope.launch {
             try {
                 while (isActive) {
-                    val changed = withContext(ioDispatcher) {
+                    val changed =
+                        withContext(ioDispatcher) {
                             idle.execute(MpdCommands.idle()).getAll("changed")
                         }
                     if (changed.any { it in REFRESHING_SUBSYSTEMS }) refresh()
@@ -396,8 +452,8 @@ class MpdClient(
     }
 
     /**
-     * Periodic `ping` so MPD's `connection_timeout` never reaps our (often quiet)
+     * Periodic `ping` so MPD's `connection_timeout` never reaps our (often quiet) command
-     * command connection, and so a dead socket is noticed promptly.
+     * connection, and so a dead socket is noticed promptly.
      */
     private fun startKeepalive() {
         keepaliveJob = scope.launch {
@@ -455,12 +511,10 @@ class MpdClient(
     private fun closeConnectionsQuietly() {
         try {
             idleConn?.close()
-        } catch (_: IOException) {
+        } catch (_: IOException) {}
-        }
         try {
             commandConn?.close()
-        } catch (_: IOException) {
+        } catch (_: IOException) {}
-        }
         idleConn = null
         commandConn = null
         closeArtConnections()
@@ -485,8 +539,8 @@ class MpdClient(
 }
 
 /**
- * Leading integer of a `track`/`disc` tag for sorting — these can carry values
+ * Leading integer of a `track`/`disc` tag for sorting — these can carry values like `"3/12"`, so we
- * like `"3/12"`, so we read the digits up front. Missing/blank tags sort last.
+ * read the digits up front. Missing/blank tags sort last.
  */
 private fun String?.leadingInt(): Int =
     this?.takeWhile { it.isDigit() }?.toIntOrNull() ?: Int.MAX_VALUE

app/src/main/kotlin/ca/ksamad/encore/mpd/MpdCommands.kt

@@ -1,32 +1,36 @@
 package ca.ksamad.encore.mpd
 
 /**
- * Typed builders for the command lines we send. These return the assembled,
+ * Typed builders for the command lines we send. These return the assembled, properly-quoted string
- * properly-quoted string (no newline) that gets handed to
+ * (no newline) that gets handed to [MpdConnection.execute]; keeping them pure makes both the
- * [MpdConnection.execute]; keeping them pure makes both the argument quoting and
+ * argument quoting and the exact wire form unit-testable without any I/O.
- * the exact wire form unit-testable without any I/O.
  *
- * This is deliberately a small, growing subset — the transport controls, option
+ * This is deliberately a small, growing subset — the transport controls, option toggles, and status
- * toggles, and status queries a remote UI needs first. Database/queue/playlist
+ * queries a remote UI needs first. Database/queue/playlist builders get added as those features
- * builders get added as those features land.
+ * land.
  */
 object MpdCommands {
-
     // --- Status queries -----------------------------------------------------
 
     fun status() = MpdProtocol.command("status")
+
     fun currentSong() = MpdProtocol.command("currentsong")
+
     fun stats() = MpdProtocol.command("stats")
 
     /**
-     * Block until one of [subsystems] changes (all of them if none given). Only
+     * Block until one of [subsystems] changes (all of them if none given). Only legal on a
-     * legal on a connection dedicated to idling — never inside a command list.
+     * connection dedicated to idling — never inside a command list.
      */
     fun idle(vararg subsystems: String) =
-        if (subsystems.isEmpty()) MpdProtocol.command("idle")
+        if (subsystems.isEmpty()) {
-        else MpdProtocol.command("idle", *subsystems)
+            MpdProtocol.command("idle")
+        } else {
+            MpdProtocol.command("idle", *subsystems)
+        }
 
     fun noidle() = MpdProtocol.command("noidle")
+
     fun ping() = MpdProtocol.command("ping")
 
     // --- Authentication -----------------------------------------------------
@@ -36,45 +40,56 @@ object MpdCommands {
     // --- Transport ----------------------------------------------------------
 
     fun play() = MpdProtocol.command("play")
+
     fun playPos(pos: Int) = MpdProtocol.command("play", pos.toString())
+
     fun playId(songId: Int) = MpdProtocol.command("playid", songId.toString())
+
     fun stop() = MpdProtocol.command("stop")
+
     fun next() = MpdProtocol.command("next")
+
     fun previous() = MpdProtocol.command("previous")
 
     /** `pause 1`/`pause 0`; with no state MPD toggles, but we send it explicitly. */
-    fun pause(paused: Boolean) =
+    fun pause(paused: Boolean) = MpdProtocol.command("pause", if (paused) "1" else "0")
-        MpdProtocol.command("pause", if (paused) "1" else "0")
 
     /** Seek to [seconds] within the currently playing song. */
-    fun seekCurrent(seconds: Double) =
+    fun seekCurrent(seconds: Double) = MpdProtocol.command("seekcur", seconds.toString())
-        MpdProtocol.command("seekcur", seconds.toString())
 
     // --- Options / mixer ----------------------------------------------------
 
-    fun setVolume(volume: Int) =
+    fun setVolume(volume: Int) = MpdProtocol.command("setvol", volume.coerceIn(0, 100).toString())
-        MpdProtocol.command("setvol", volume.coerceIn(0, 100).toString())
 
     fun repeat(on: Boolean) = MpdProtocol.command("repeat", if (on) "1" else "0")
+
     fun random(on: Boolean) = MpdProtocol.command("random", if (on) "1" else "0")
+
     fun single(on: Boolean) = MpdProtocol.command("single", if (on) "1" else "0")
+
     fun consume(on: Boolean) = MpdProtocol.command("consume", if (on) "1" else "0")
 
     // --- Queue --------------------------------------------------------------
 
     fun playlistInfo() = MpdProtocol.command("playlistinfo")
+
     fun clear() = MpdProtocol.command("clear")
+
     /**
-     * Add a single file/URI to the queue. With no [position] it appends to the
+     * Add a single file/URI to the queue. With no [position] it appends to the end; otherwise the
-     * end; otherwise the value is passed as `add`'s positional argument — `"+0"`
+     * value is passed as `add`'s positional argument — `"+0"` inserts right after the currently
-     * inserts right after the currently playing song ("play next").
+     * playing song ("play next").
      */
-    fun add(uri: String, position: String? = null) =
+    fun add(
+        uri: String,
+        position: String? = null,
+    ) =
         if (position == null) {
             MpdProtocol.command("add", uri)
         } else {
             MpdProtocol.command("add", uri, position)
         }
+
     fun deleteId(songId: Int) = MpdProtocol.command("deleteid", songId.toString())
 
     // --- Database / library -------------------------------------------------
@@ -85,22 +100,36 @@ object MpdCommands {
     /**
      * Append every track of an album to the queue (optionally scoped to an artist).
      *
-     * When [position] is given it is passed through as `findadd`'s `position`
+     * When [position] is given it is passed through as `findadd`'s `position` argument, controlling
-     * argument, controlling where the tracks land. MPD accepts an absolute index
+     * where the tracks land. MPD accepts an absolute index or a relative one — `"+0"` inserts right
-     * or a relative one — `"+0"` inserts right after the currently playing song
+     * after the currently playing song (i.e. "play next"). Omit it to append to the end of the
-     * (i.e. "play next"). Omit it to append to the end of the queue.
+     * queue.
      */
-    fun findAddAlbum(album: String, albumArtist: String?, position: String? = null): String {
+    fun findAddAlbum(
+        album: String,
+        albumArtist: String?,
+        position: String? = null,
+    ): String {
         val args = buildList {
-            add("album"); add(album)
+            add("album")
-            if (!albumArtist.isNullOrEmpty()) { add("albumartist"); add(albumArtist) }
+            add(album)
-            if (position != null) { add("position"); add(position) }
+            if (!albumArtist.isNullOrEmpty()) {
+                add("albumartist")
+                add(albumArtist)
+            }
+            if (position != null) {
+                add("position")
+                add(position)
+            }
         }
         return MpdProtocol.command("findadd", *args.toTypedArray())
     }
 
     /** Every track of an album (optionally scoped to an artist), in database order. */
-    fun findAlbumTracks(album: String, albumArtist: String?) =
+    fun findAlbumTracks(
+        album: String,
+        albumArtist: String?,
+    ) =
         if (albumArtist.isNullOrEmpty()) {
             MpdProtocol.command("find", "album", album)
         } else {
@@ -108,7 +137,10 @@ object MpdCommands {
         }
 
     /** First track of an album — used to resolve a URI for album-art lookup. */
-    fun findFirstTrack(album: String, albumArtist: String?) =
+    fun findFirstTrack(
+        album: String,
+        albumArtist: String?,
+    ) =
         if (albumArtist.isNullOrEmpty()) {
             MpdProtocol.command("find", "album", album, "window", "0:1")
         } else {
@@ -118,10 +150,16 @@ object MpdCommands {
     // --- Album art ----------------------------------------------------------
 
     /** Folder cover art for [uri]'s directory, starting at [offset] (chunked binary). */
-    fun albumArt(uri: String, offset: Int) = MpdProtocol.command("albumart", uri, offset.toString())
+    fun albumArt(
+        uri: String,
+        offset: Int,
+    ) = MpdProtocol.command("albumart", uri, offset.toString())
 
     /** Embedded picture from the file at [uri], starting at [offset] (chunked binary). */
-    fun readPicture(uri: String, offset: Int) = MpdProtocol.command("readpicture", uri, offset.toString())
+    fun readPicture(
+        uri: String,
+        offset: Int,
+    ) = MpdProtocol.command("readpicture", uri, offset.toString())
 
     /** Raise the per-response binary chunk size so art transfers in fewer round-trips. */
     fun binaryLimit(bytes: Int) = MpdProtocol.command("binarylimit", bytes.toString())

app/src/main/kotlin/ca/ksamad/encore/mpd/MpdConnection.kt

@@ -11,36 +11,33 @@ import java.net.InetSocketAddress
 import java.net.Socket
 
 /**
- * A single synchronous MPD connection: the raw text protocol over a byte
+ * A single synchronous MPD connection: the raw text protocol over a byte stream. One command is
- * stream. One command is written, one response is read back; calls are **not**
+ * written, one response is read back; calls are **not** thread-safe and must be serialized by the
- * thread-safe and must be serialized by the caller (a higher-level client will
+ * caller (a higher-level client will own a [MpdConnection] behind a mutex, and a second one parked
- * own a [MpdConnection] behind a mutex, and a second one parked in `idle`).
+ * in `idle`).
  *
- * The transport is an [InputStream]/[OutputStream] pair rather than a [Socket]
+ * The transport is an [InputStream]/[OutputStream] pair rather than a [Socket] so the protocol can
- * so the protocol can be exercised against in-memory streams in tests. Use
+ * be exercised against in-memory streams in tests. Use [connect] for a real TCP connection.
- * [connect] for a real TCP connection.
  *
- * Reading is done at the byte level (not via a [java.io.Reader]) because
+ * Reading is done at the byte level (not via a [java.io.Reader]) because responses can interleave
- * responses can interleave UTF-8 text lines with raw binary payloads, and a
+ * UTF-8 text lines with raw binary payloads, and a buffered character reader would happily swallow
- * buffered character reader would happily swallow bytes past a line boundary.
+ * bytes past a line boundary.
  */
 class MpdConnection(
     private val input: InputStream,
     private val output: OutputStream,
     private val closer: Closeable? = null,
 ) : Closeable {
-
     /** Protocol version from the greeting, e.g. `0.23.5`. Null until [handshake]. */
     var protocolVersion: String? = null
         private set
 
     /**
-     * Read and validate the server greeting (`OK MPD <version>`). Must be called
+     * Read and validate the server greeting (`OK MPD <version>`). Must be called exactly once,
-     * exactly once, before any command. Returns the protocol version.
+     * before any command. Returns the protocol version.
      */
     fun handshake(): String {
-        val line = readLine()
+        val line = readLine() ?: throw MpdConnectionException("connection closed before greeting")
-            ?: throw MpdConnectionException("connection closed before greeting")
         if (!line.startsWith(MpdProtocol.GREETING_PREFIX)) {
             throw MpdConnectionException("unexpected greeting: $line")
         }
@@ -50,8 +47,8 @@ class MpdConnection(
     }
 
     /**
-     * Send one command line (name + already-assembled string, no newline) and
+     * Send one command line (name + already-assembled string, no newline) and read its response up
-     * read its response up to the terminating `OK`.
+     * to the terminating `OK`.
      *
      * @throws MpdAckException if the server replied `ACK …`.
      * @throws MpdConnectionException on EOF or a malformed response.
@@ -62,14 +59,15 @@ class MpdConnection(
     }
 
     /** Convenience: [MpdProtocol.command] + [execute]. */
-    fun execute(name: String, vararg args: String): MpdResponse =
+    fun execute(
-        execute(MpdProtocol.command(name, *args))
+        name: String,
+        vararg args: String,
+    ): MpdResponse = execute(MpdProtocol.command(name, *args))
 
     /**
-     * Run several commands as a single batch (`command_list_ok_begin`), returning
+     * Run several commands as a single batch (`command_list_ok_begin`), returning one [MpdResponse]
-     * one [MpdResponse] per command in order. One network round-trip instead of
+     * per command in order. One network round-trip instead of N — worth it on a slow server. Each
-     * N — worth it on a slow server. Each command's response is delimited by
+     * command's response is delimited by `list_OK`, and the batch ends with a final `OK`.
-     * `list_OK`, and the batch ends with a final `OK`.
      */
     fun executeList(vararg commandLines: String): List<MpdResponse> {
         val payload = buildString {
@@ -97,22 +95,26 @@ class MpdConnection(
         val values = ArrayList<Pair<String, String>>()
         var binary: ByteArray? = null
         while (true) {
-            val line = readLine()
+            val line = readLine() ?: throw MpdConnectionException("connection closed mid-response")
-                ?: throw MpdConnectionException("connection closed mid-response")
             when {
                 // OK ends a command; list_OK ends one command within a command list.
-                line == MpdProtocol.OK || line == MpdProtocol.LIST_OK ->
+                line == MpdProtocol.OK || line == MpdProtocol.LIST_OK -> {
                     return MpdResponse(values, binary)
-                line.startsWith("ACK ") ->
+                }
+
+                line.startsWith("ACK ") -> {
                     throw MpdAckException.parse(line)
                         ?: MpdConnectionException("malformed ACK: $line")
+                }
+
                 else -> {
                     val sep = line.indexOf(": ")
                     if (sep < 0) continue // tolerate stray lines rather than fail
                     val key = line.substring(0, sep)
                     val value = line.substring(sep + 2)
                     if (key == "binary") {
-                        binary = readBinary(
+                        binary =
+                            readBinary(
                                 value.toIntOrNull()
                                     ?: throw MpdConnectionException("bad binary size: $value")
                             )
@@ -143,7 +145,7 @@ class MpdConnection(
         var off = 0
         while (off < size) {
             val n = input.read(data, off, size - off)
-            if (n == -1) throw MpdConnectionException("EOF after ${off}/$size binary bytes")
+            if (n == -1) throw MpdConnectionException("EOF after $off/$size binary bytes")
             off += n
         }
         input.read() // trailing newline that follows the binary block
@@ -154,20 +156,19 @@ class MpdConnection(
         // Best-effort: closing the socket tears down both streams.
         try {
             closer?.close() ?: output.close()
-        } catch (_: IOException) {
+        } catch (_: IOException) {}
-        }
     }
 
     companion object {
         const val DEFAULT_PORT = 6600
 
         /**
-         * Open a TCP connection to an MPD server and complete the greeting
+         * Open a TCP connection to an MPD server and complete the greeting handshake. Blocking —
-         * handshake. Blocking — call off the main thread.
+         * call off the main thread.
          *
          * @param connectTimeoutMs socket connect timeout.
-         * @param readTimeoutMs `SO_TIMEOUT`; 0 means block forever (needed for
+         * @param readTimeoutMs `SO_TIMEOUT`; 0 means block forever (needed for the `idle`
-         *   the `idle` connection, which parks indefinitely).
+         *   connection, which parks indefinitely).
          */
         fun connect(
             host: String,
@@ -180,7 +181,8 @@ class MpdConnection(
                 socket.connect(InetSocketAddress(host, port), connectTimeoutMs)
                 socket.soTimeout = readTimeoutMs
                 socket.tcpNoDelay = true
-                val conn = MpdConnection(
+                val conn =
+                    MpdConnection(
                         input = BufferedInputStream(socket.getInputStream()),
                         output = BufferedOutputStream(socket.getOutputStream()),
                         closer = socket,

app/src/main/kotlin/ca/ksamad/encore/mpd/MpdException.kt

@@ -3,29 +3,31 @@ package ca.ksamad.encore.mpd
 import java.io.IOException
 
 /** Base type for every failure the MPD layer can raise. */
-sealed class MpdException(message: String, cause: Throwable? = null) :
+sealed class MpdException(
-    IOException(message, cause)
+    message: String,
+    cause: Throwable? = null,
+) : IOException(message, cause)
 
 /**
- * A transport-level problem: the socket closed, the greeting was malformed, an
+ * A transport-level problem: the socket closed, the greeting was malformed, an EOF arrived
- * EOF arrived mid-response, etc. These are the failures that mean "the
+ * mid-response, etc. These are the failures that mean "the connection can no longer be trusted", as
- * connection can no longer be trusted", as opposed to a command the server
+ * opposed to a command the server simply rejected.
- * simply rejected.
  */
-class MpdConnectionException(message: String, cause: Throwable? = null) :
+class MpdConnectionException(
-    MpdException(message, cause)
+    message: String,
+    cause: Throwable? = null,
+) : MpdException(message, cause)
 
 /**
- * The server understood us but refused the command, i.e. it replied with an
+ * The server understood us but refused the command, i.e. it replied with an `ACK` line. The wire
- * `ACK` line. The wire format is:
+ * format is:
- *
  * ```
  * ACK [error@command_listNum] {current_command} message_text
  * ```
  *
- * where `error` is one of MPD's numeric `ACK_ERROR_*` codes (see [Code]),
+ * where `error` is one of MPD's numeric `ACK_ERROR_*` codes (see [Code]), `command_listNum` is the
- * `command_listNum` is the 0-based offset of the failing command inside a
+ * 0-based offset of the failing command inside a command list (0 for a bare command), and
- * command list (0 for a bare command), and `current_command` names it.
+ * `current_command` names it.
  */
 class MpdAckException(
     val code: Int,
@@ -33,7 +35,6 @@ class MpdAckException(
     val command: String,
     val serverMessage: String,
 ) : MpdException("ACK [$code@$commandListNum] {$command} $serverMessage") {
-
     /** MPD's `ACK_ERROR_*` constants, for callers that want to branch on them. */
     object Code {
         const val NOT_LIST = 1
@@ -58,8 +59,8 @@ class MpdAckException(
         private val PATTERN = Regex("""ACK \[(\d+)@(\d+)\] \{([^}]*)\} ?(.*)""")
 
         /**
-         * Parse a raw `ACK …` response line. Returns `null` if [line] is not a
+         * Parse a raw `ACK …` response line. Returns `null` if [line] is not a well-formed ACK, so
-         * well-formed ACK, so the caller can decide how to treat garbage.
+         * the caller can decide how to treat garbage.
          */
         fun parse(line: String): MpdAckException? {
             val m = PATTERN.matchEntire(line) ?: return null

app/src/main/kotlin/ca/ksamad/encore/mpd/MpdProtocol.kt

@@ -1,12 +1,11 @@
 package ca.ksamad.encore.mpd
 
 /**
- * Pure, connection-independent helpers for speaking the MPD text protocol:
+ * Pure, connection-independent helpers for speaking the MPD text protocol: argument quoting and
- * argument quoting and command-string assembly. Kept separate from
+ * command-string assembly. Kept separate from [MpdConnection] so it can be unit-tested without any
- * [MpdConnection] so it can be unit-tested without any I/O.
+ * I/O.
  */
 object MpdProtocol {
-
     /** Every server greeting starts with this, followed by the protocol version. */
     const val GREETING_PREFIX = "OK MPD "
 
@@ -17,11 +16,10 @@ object MpdProtocol {
     const val LIST_OK = "list_OK"
 
     /**
-     * Quote a single command argument. MPD's tokenizer treats a bare token as
+     * Quote a single command argument. MPD's tokenizer treats a bare token as ending at the next
-     * ending at the next whitespace, so any argument is wrapped in double quotes
+     * whitespace, so any argument is wrapped in double quotes with embedded `"` and `\`
-     * with embedded `"` and `\` backslash-escaped. Always quoting (even numbers
+     * backslash-escaped. Always quoting (even numbers and empty strings) is accepted by the server
-     * and empty strings) is accepted by the server and keeps callers from having
+     * and keeps callers from having to reason about which values are "safe".
-     * to reason about which values are "safe".
      */
     fun quote(arg: String): String {
         val sb = StringBuilder(arg.length + 2)
@@ -35,11 +33,13 @@ object MpdProtocol {
     }
 
     /**
-     * Assemble a full command line (without the trailing newline) from a command
+     * Assemble a full command line (without the trailing newline) from a command name and its
-     * name and its arguments. The name is emitted verbatim; every argument is
+     * arguments. The name is emitted verbatim; every argument is [quote]d.
-     * [quote]d.
      */
-    fun command(name: String, vararg args: String): String {
+    fun command(
+        name: String,
+        vararg args: String,
+    ): String {
         if (args.isEmpty()) return name
         return buildString {
             append(name)

app/src/main/kotlin/ca/ksamad/encore/mpd/MpdResponse.kt

@@ -1,31 +1,26 @@
 package ca.ksamad.encore.mpd
 
 /**
- * The parsed result of a single successful command: the ordered `key: value`
+ * The parsed result of a single successful command: the ordered `key: value` lines the server sent
- * lines the server sent before its `OK`, plus an optional [binary] payload for
+ * before its `OK`, plus an optional [binary] payload for commands like `albumart`/`readpicture`.
- * commands like `albumart`/`readpicture`.
  *
- * Order is preserved because several commands (e.g. `playlistinfo`, `lsinfo`)
+ * Order is preserved because several commands (e.g. `playlistinfo`, `lsinfo`) return repeated
- * return repeated blocks that are only separable by position — a new object
+ * blocks that are only separable by position — a new object begins each time a delimiting key such
- * begins each time a delimiting key such as `file` reappears. Use [split] to
+ * as `file` reappears. Use [split] to chop such a response into per-object maps.
- * chop such a response into per-object maps.
  */
 class MpdResponse(
     val values: List<Pair<String, String>>,
     val binary: ByteArray? = null,
 ) {
     /** First value for [key], or `null` if absent. */
-    operator fun get(key: String): String? =
+    operator fun get(key: String): String? = values.firstOrNull { it.first == key }?.second
-        values.firstOrNull { it.first == key }?.second
 
     /** All values for [key], in order. */
-    fun getAll(key: String): List<String> =
+    fun getAll(key: String): List<String> = values.filter { it.first == key }.map { it.second }
-        values.filter { it.first == key }.map { it.second }
 
     /**
-     * Flatten to a map of first-seen values. Safe for commands whose keys are
+     * Flatten to a map of first-seen values. Safe for commands whose keys are unique (`status`,
-     * unique (`status`, `currentsong`, `stats`); lossy for repeated blocks —
+     * `currentsong`, `stats`); lossy for repeated blocks — use [split] there instead.
-     * use [split] there instead.
      */
     fun toMap(): Map<String, String> {
         val out = LinkedHashMap<String, String>(values.size)
@@ -34,9 +29,9 @@ class MpdResponse(
     }
 
     /**
-     * Split a multi-object response into one map per object. A new object starts
+     * Split a multi-object response into one map per object. A new object starts at every
-     * at every occurrence of [delimiter] (default `file`, the first key MPD emits
+     * occurrence of [delimiter] (default `file`, the first key MPD emits for a song/file entry).
-     * for a song/file entry). Lines before the first delimiter are ignored.
+     * Lines before the first delimiter are ignored.
      */
     fun split(delimiter: String = "file"): List<Map<String, String>> {
         val result = ArrayList<Map<String, String>>()

app/src/main/kotlin/ca/ksamad/encore/mpd/model/MpdAlbum.kt

@@ -9,9 +9,9 @@ data class MpdAlbum(
 ) {
     companion object {
         /**
-         * Parse the response of `list album group albumartist`. MPD emits an
+         * Parse the response of `list album group albumartist`. MPD emits an `AlbumArtist:` line
-         * `AlbumArtist:` line followed by the `Album:` lines belonging to it, so
+         * followed by the `Album:` lines belonging to it, so we track the current artist and attach
-         * we track the current artist and attach it to each album.
+         * it to each album.
          */
         fun listFrom(response: MpdResponse): List<MpdAlbum> {
             val albums = ArrayList<MpdAlbum>()

app/src/main/kotlin/ca/ksamad/encore/mpd/model/MpdSong.kt

@@ -1,13 +1,12 @@
 package ca.ksamad.encore.mpd.model
 
 /**
- * A song/file entry, parsed from the metadata block MPD emits for `currentsong`,
+ * A song/file entry, parsed from the metadata block MPD emits for `currentsong`, `playlistinfo`,
- * `playlistinfo`, `find`, `lsinfo`, etc. [uri] (the `file` key) is the only
+ * `find`, `lsinfo`, etc. [uri] (the `file` key) is the only required field; every tag is optional
- * required field; every tag is optional because the server only sends tags the
+ * because the server only sends tags the file actually has.
- * file actually has.
  *
- * Tags are kept as raw strings — `track`/`disc` can carry values like `"3/12"`,
+ * Tags are kept as raw strings — `track`/`disc` can carry values like `"3/12"`, and normalising
- * and normalising them is a display concern left to the UI layer.
+ * them is a display concern left to the UI layer.
  */
 data class MpdSong(
     val uri: String,
@@ -25,9 +24,8 @@ data class MpdSong(
 ) {
     companion object {
         /**
-         * Parse one song from a metadata map. Returns `null` when there is no
+         * Parse one song from a metadata map. Returns `null` when there is no `file` key (i.e. this
-         * `file` key (i.e. this block is not a song — e.g. a `directory` entry
+         * block is not a song — e.g. a `directory` entry in an `lsinfo` listing).
-         * in an `lsinfo` listing).
          */
         fun from(values: Map<String, String>): MpdSong? {
             val uri = values["file"] ?: return null
@@ -41,8 +39,7 @@ data class MpdSong(
                 disc = values["Disc"],
                 date = values["Date"],
                 genre = values["Genre"],
-                duration = values["duration"]?.toDoubleOrNull()
+                duration = values["duration"]?.toDoubleOrNull() ?: values["Time"]?.toDoubleOrNull(),
-                    ?: values["Time"]?.toDoubleOrNull(),
                 pos = values["Pos"]?.toIntOrNull(),
                 id = values["Id"]?.toIntOrNull(),
             )

app/src/main/kotlin/ca/ksamad/encore/mpd/model/MpdStatistics.kt

@@ -1,8 +1,8 @@
 package ca.ksamad.encore.mpd.model
 
 /**
- * Database/server statistics from a `stats` response. Durations are in seconds
+ * Database/server statistics from a `stats` response. Durations are in seconds and the update
- * and the update timestamp is Unix epoch seconds, both as MPD reports them.
+ * timestamp is Unix epoch seconds, both as MPD reports them.
  */
 data class MpdStatistics(
     val artists: Int,
@@ -14,7 +14,8 @@ data class MpdStatistics(
     val dbUpdateEpochSeconds: Long,
 ) {
     companion object {
-        fun from(values: Map<String, String>): MpdStatistics = MpdStatistics(
+        fun from(values: Map<String, String>): MpdStatistics =
+            MpdStatistics(
                 artists = values["artists"]?.toIntOrNull() ?: 0,
                 albums = values["albums"]?.toIntOrNull() ?: 0,
                 songs = values["songs"]?.toIntOrNull() ?: 0,

app/src/main/kotlin/ca/ksamad/encore/mpd/model/MpdStatus.kt

@@ -2,10 +2,14 @@ package ca.ksamad.encore.mpd.model
 
 /** Player transport state as reported by the `state` field of `status`. */
 enum class PlayerState {
-    PLAY, PAUSE, STOP, UNKNOWN;
+    PLAY,
+    PAUSE,
+    STOP,
+    UNKNOWN;
 
     companion object {
-        fun parse(raw: String?): PlayerState = when (raw) {
+        fun parse(raw: String?): PlayerState =
+            when (raw) {
                 "play" -> PLAY
                 "pause" -> PAUSE
                 "stop" -> STOP
@@ -15,11 +19,11 @@ enum class PlayerState {
 }
 
 /**
- * A snapshot of the player, parsed from a `status` response. Fields absent from
+ * A snapshot of the player, parsed from a `status` response. Fields absent from the response (e.g.
- * the response (e.g. `song`/`elapsed` while stopped) are `null`.
+ * `song`/`elapsed` while stopped) are `null`.
  *
- * See the MPD protocol docs for field semantics. Only the fields a remote UI
+ * See the MPD protocol docs for field semantics. Only the fields a remote UI actually drives are
- * actually drives are surfaced here; more can be added as needed.
+ * surfaced here; more can be added as needed.
  */
 data class MpdStatus(
     val volume: Int?, // 0..100; null when MPD reports -1 (output closed / volume unavailable)
@@ -41,7 +45,8 @@ data class MpdStatus(
     val error: String?, // last player error, if any
 ) {
     companion object {
-        fun from(values: Map<String, String>): MpdStatus = MpdStatus(
+        fun from(values: Map<String, String>): MpdStatus =
+            MpdStatus(
                 volume = values["volume"]?.toIntOrNull()?.takeIf { it >= 0 },
                 repeat = values["repeat"] == "1",
                 random = values["random"] == "1",

app/src/main/kotlin/ca/ksamad/encore/playback/ArtImageLoader.kt

@@ -18,15 +18,16 @@ import okio.Path.Companion.toOkioPath
  * Builds the Coil [ImageLoader] that serves MPD cover art. Art bytes come from
  * [MpdConnectionManager.fetchArt] via a custom [Fetcher].
  *
- * Coil's disk cache is only auto-managed by its network fetchers, so a custom
+ * Coil's disk cache is only auto-managed by its network fetchers, so a custom fetcher must
- * fetcher must read/write the [DiskCache] itself — otherwise art is only
+ * read/write the [DiskCache] itself — otherwise art is only memory-cached and every cold start
- * memory-cached and every cold start re-fetches from the server. [MpdArtFetcher]
+ * re-fetches from the server. [MpdArtFetcher] therefore checks the disk cache first, and
- * therefore checks the disk cache first, and write-through-caches misses, so each
+ * write-through-caches misses, so each cover is fetched from the (tiny) server exactly once, ever.
- * cover is fetched from the (tiny) server exactly once, ever.
  */
 object ArtImageLoader {
-
+    fun create(
-    fun create(context: PlatformContext, manager: MpdConnectionManager): ImageLoader =
+        context: PlatformContext,
+        manager: MpdConnectionManager,
+    ): ImageLoader =
         ImageLoader.Builder(context)
             .components {
                 add(MpdArtKeyer(), MpdArtData::class)
@@ -41,13 +42,17 @@ object ArtImageLoader {
             .build()
 
     /** Stable cache key per art request; shared by the keyer and the disk cache. */
-    private fun cacheKey(data: MpdArtData): String = when (data) {
+    private fun cacheKey(data: MpdArtData): String =
+        when (data) {
             is SongArt -> "song:${data.uri}"
             is AlbumArt -> "album:${data.albumArtist.orEmpty()}/${data.album}"
         }
 
     private class MpdArtKeyer : Keyer<MpdArtData> {
-        override fun key(data: MpdArtData, options: Options): String = cacheKey(data)
+        override fun key(
+            data: MpdArtData,
+            options: Options,
+        ): String = cacheKey(data)
     }
 
     private class MpdArtFetcher(
@@ -55,7 +60,6 @@ object ArtImageLoader {
         private val diskCache: DiskCache?,
         private val fetch: suspend (MpdArtData) -> ByteArray?,
     ) : Fetcher {
-
         override suspend fun fetch(): FetchResult? {
             val key = cacheKey(data)
 
@@ -80,7 +84,10 @@ object ArtImageLoader {
             )
         }
 
-        private fun writeToDiskCache(key: String, bytes: ByteArray): DiskCache.Snapshot? {
+        private fun writeToDiskCache(
+            key: String,
+            bytes: ByteArray,
+        ): DiskCache.Snapshot? {
             val cache = diskCache ?: return null
             val editor = cache.openEditor(key) ?: return null
             return try {
@@ -96,8 +103,10 @@ object ArtImageLoader {
             snapshot: DiskCache.Snapshot,
             key: String,
             dataSource: DataSource,
-        ): SourceFetchResult = SourceFetchResult(
+        ): SourceFetchResult =
-            source = ImageSource(
+            SourceFetchResult(
+                source =
+                    ImageSource(
                         file = snapshot.data,
                         fileSystem = diskCache!!.fileSystem,
                         diskCacheKey = key,
@@ -107,11 +116,13 @@ object ArtImageLoader {
                 dataSource = dataSource,
             )
 
-        class Factory(
+        class Factory(private val fetch: suspend (MpdArtData) -> ByteArray?) :
-            private val fetch: suspend (MpdArtData) -> ByteArray?,
+            Fetcher.Factory<MpdArtData> {
-        ) : Fetcher.Factory<MpdArtData> {
+            override fun create(
-            override fun create(data: MpdArtData, options: Options, imageLoader: ImageLoader): Fetcher =
+                data: MpdArtData,
-                MpdArtFetcher(data, imageLoader.diskCache, fetch)
+                options: Options,
+                imageLoader: ImageLoader,
+            ): Fetcher = MpdArtFetcher(data, imageLoader.diskCache, fetch)
         }
     }
 }

app/src/main/kotlin/ca/ksamad/encore/playback/MpdArt.kt

@@ -1,9 +1,9 @@
 package ca.ksamad.encore.playback
 
 /**
- * A request for a piece of MPD cover art, used as the model handed to Coil. The
+ * A request for a piece of MPD cover art, used as the model handed to Coil. The concrete type
- * concrete type doubles as the cache key (see the keyer in [ArtImageLoader]), so
+ * doubles as the cache key (see the keyer in [ArtImageLoader]), so the same song/album resolves to
- * the same song/album resolves to the same cached image.
+ * the same cached image.
  */
 sealed interface MpdArtData
 
@@ -11,4 +11,7 @@ sealed interface MpdArtData
 data class SongArt(val uri: String) : MpdArtData
 
 /** Cover art for an album (a representative track is resolved server-side). */
-data class AlbumArt(val album: String, val albumArtist: String?) : MpdArtData
+data class AlbumArt(
+    val album: String,
+    val albumArtist: String?,
+) : MpdArtData

app/src/main/kotlin/ca/ksamad/encore/playback/MpdConnectionManager.kt

@@ -21,19 +21,16 @@ import kotlinx.coroutines.flow.stateIn
 import kotlinx.coroutines.launch
 
 /**
- * App-scoped owner of the single [MpdClient]. Living at the [Application] level
+ * App-scoped owner of the single [MpdClient]. Living at the [Application] level (not in a
- * (not in a ViewModel) means the connection survives Activity recreation and
+ * ViewModel) means the connection survives Activity recreation and keeps running while
- * keeps running while [PlaybackService] holds the app in the foreground — which
+ * [PlaybackService] holds the app in the foreground — which is what makes the OS media session /
- * is what makes the OS media session / notification / cast volume work when the
+ * notification / cast volume work when the user has left the UI.
- * user has left the UI.
  *
- * Both the UI (via `PlayerViewModel`) and [PlaybackService] talk to this same
+ * Both the UI (via `PlayerViewModel`) and [PlaybackService] talk to this same instance: the UI
- * instance: the UI observes the flows and issues commands; the service mirrors
+ * observes the flows and issues commands; the service mirrors the flows into a `MediaSessionCompat`
- * the flows into a `MediaSessionCompat` and routes media-button / volume-key
+ * and routes media-button / volume-key callbacks back here.
- * callbacks back here.
  */
 class MpdConnectionManager(context: Context) {
-
     private val appContext = context.applicationContext
     private val client = MpdClient()
     private val settingsRepo = SettingsRepository(appContext)
@@ -47,8 +44,8 @@ class MpdConnectionManager(context: Context) {
     val serverHost: StateFlow<String?> = _serverHost
 
     /** Persisted settings (defaulted) for seeding the connect form. */
-    val settings: StateFlow<ConnectionSettings> = settingsRepo.settings
+    val settings: StateFlow<ConnectionSettings> =
-        .stateIn(scope, SharingStarted.Eagerly, ConnectionSettings.DEFAULT)
+        settingsRepo.settings.stateIn(scope, SharingStarted.Eagerly, ConnectionSettings.DEFAULT)
 
     // True until the startup auto-connect decision has been made.
     private val _bootstrapping = MutableStateFlow(true)
@@ -56,8 +53,7 @@ class MpdConnectionManager(context: Context) {
 
     // Optimistic volume target so rapid nudges accumulate instead of each reading
     // the same stale server value; cleared once the server confirms it.
-    @Volatile
+    @Volatile private var pendingVolume: Int? = null
-    private var pendingVolume: Int? = null
 
     // Volume writes are coalesced through a conflated channel + throttle so that
     // holding a volume key (or dragging the OS remote-volume slider) sends at
@@ -91,15 +87,20 @@ class MpdConnectionManager(context: Context) {
             connectionState.collect { st ->
                 when (st) {
                     is MpdConnectionState.Connected -> PlaybackService.start(appContext)
+
                     is MpdConnectionState.Disconnected,
                     is MpdConnectionState.Error -> PlaybackService.stop(appContext)
+
                     is MpdConnectionState.Connecting -> Unit
                 }
             }
         }
     }
 
-    fun connect(host: String, port: Int) {
+    fun connect(
+        host: String,
+        port: Int,
+    ) {
         val trimmed = host.trim()
         _serverHost.value = trimmed
         scope.launch {
@@ -120,28 +121,48 @@ class MpdConnectionManager(context: Context) {
     }
 
     fun resume() = fire { pause(false) }
+
     fun pause() = fire { pause(true) }
+
     fun stop() = fire { stop() }
+
     fun clearQueue() = fire { clearQueue() }
+
     fun next() = fire { next() }
+
     fun previous() = fire { previous() }
+
     fun togglePlayPause() = fire { togglePause() }
+
     fun seekTo(seconds: Double) = fire { seekCurrent(seconds) }
+
     fun setVolume(volume: Int) {
         // Coalesced + throttled by the volumeRequests consumer (see init).
         volumeRequests.trySend(volume.coerceIn(0, 100))
     }
+
     fun setRepeat(on: Boolean) = fire { setRepeat(on) }
+
     fun setRandom(on: Boolean) = fire { setRandom(on) }
+
     fun setConsume(on: Boolean) = fire { setConsume(on) }
 
-    fun playAlbum(album: String, albumArtist: String?) = fire { playAlbum(album, albumArtist) }
+    fun playAlbum(
+        album: String,
+        albumArtist: String?,
+    ) = fire { playAlbum(album, albumArtist) }
 
     /** Append an album to the end of the queue without changing playback. */
-    fun queueAlbum(album: String, albumArtist: String?) = fire { queueAlbum(album, albumArtist) }
+    fun queueAlbum(
+        album: String,
+        albumArtist: String?,
+    ) = fire { queueAlbum(album, albumArtist) }
 
     /** Insert an album right after the current track so it plays next. */
-    fun playAlbumNext(album: String, albumArtist: String?) = fire { playAlbumNext(album, albumArtist) }
+    fun playAlbumNext(
+        album: String,
+        albumArtist: String?,
+    ) = fire { playAlbumNext(album, albumArtist) }
 
     /** Append a single track to the end of the queue. */
     fun queueTrack(uri: String) = fire { queueTrack(uri) }
@@ -150,12 +171,14 @@ class MpdConnectionManager(context: Context) {
     fun playTrackNext(uri: String) = fire { playTrackNext(uri) }
 
     /** One-shot album track-list fetch; returns empty on any failure. */
-    suspend fun loadAlbumTracks(album: String, albumArtist: String?): List<MpdSong> =
+    suspend fun loadAlbumTracks(
+        album: String,
+        albumArtist: String?,
+    ): List<MpdSong> =
         runCatching { client.albumTracks(album, albumArtist) }.getOrDefault(emptyList())
 
     /** One-shot server statistics fetch; returns null on any failure. */
-    suspend fun loadStatistics(): MpdStatistics? =
+    suspend fun loadStatistics(): MpdStatistics? = runCatching { client.statistics() }.getOrNull()
-        runCatching { client.statistics() }.getOrNull()
 
     /** Jump to a queue entry by its stable song id. */
     fun playQueueItem(songId: Int) = fire { playId(songId) }
@@ -164,29 +187,37 @@ class MpdConnectionManager(context: Context) {
     fun removeQueueItem(songId: Int) = fire { removeQueueItem(songId) }
 
     /** Re-insert a track at an absolute queue position (undo a removal). */
-    fun addTrackAt(uri: String, position: Int) = fire { addTrackAt(uri, position) }
+    fun addTrackAt(
+        uri: String,
+        position: Int,
+    ) = fire { addTrackAt(uri, position) }
 
     /** One-shot library fetch; returns empty on any failure. */
-    suspend fun loadAlbums(): List<MpdAlbum> = runCatching { client.albums() }.getOrDefault(emptyList())
+    suspend fun loadAlbums(): List<MpdAlbum> =
+        runCatching { client.albums() }.getOrDefault(emptyList())
 
     /** One-shot play-queue fetch; returns empty on any failure. */
-    suspend fun loadQueue(): List<MpdSong> = runCatching { client.queue() }.getOrDefault(emptyList())
+    suspend fun loadQueue(): List<MpdSong> =
+        runCatching { client.queue() }.getOrDefault(emptyList())
 
     /** Fetch cover-art bytes for Coil (null on miss/failure). */
-    suspend fun fetchArt(data: MpdArtData): ByteArray? = runCatching {
+    suspend fun fetchArt(data: MpdArtData): ByteArray? =
+        runCatching {
                 when (data) {
                     is SongArt -> client.songArt(data.uri)
                     is AlbumArt -> client.albumArt(data.album, data.albumArtist)
                 }
-    }.getOrNull()
+            }
+            .getOrNull()
 
     /**
-     * True when we own the volume: connected to a server that exposes a mixer.
+     * True when we own the volume: connected to a server that exposes a mixer. Used to decide
-     * Used to decide whether hardware volume keys drive the *server* (silently,
+     * whether hardware volume keys drive the *server* (silently, in-app) or fall through to the
-     * in-app) or fall through to the device's own local volume.
+     * device's own local volume.
      */
     val isControllingVolume: Boolean
-        get() = connectionState.value is MpdConnectionState.Connected && status.value?.volume != null
+        get() =
+            connectionState.value is MpdConnectionState.Connected && status.value?.volume != null
 
     /** Relative volume change (from a hardware key / VolumeProvider), accumulating. */
     fun nudgeVolume(up: Boolean) {

app/src/main/kotlin/ca/ksamad/encore/playback/PlaybackService.kt

@@ -18,17 +18,17 @@ import androidx.core.content.ContextCompat
 import androidx.media.VolumeProviderCompat
 import androidx.media.app.NotificationCompat.MediaStyle
 import androidx.media.session.MediaButtonReceiver
-import coil3.SingletonImageLoader
-import coil3.request.ImageRequest
-import coil3.request.SuccessResult
-import coil3.toBitmap
-import ca.ksamad.encore.MainActivity
 import ca.ksamad.encore.EncoreApplication
+import ca.ksamad.encore.MainActivity
 import ca.ksamad.encore.R
 import ca.ksamad.encore.mpd.MpdConnectionState
 import ca.ksamad.encore.mpd.model.MpdSong
 import ca.ksamad.encore.mpd.model.MpdStatus
 import ca.ksamad.encore.mpd.model.PlayerState
+import coil3.SingletonImageLoader
+import coil3.request.ImageRequest
+import coil3.request.SuccessResult
+import coil3.toBitmap
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.SupervisorJob
@@ -41,18 +41,17 @@ import kotlinx.coroutines.launch
 
 /**
  * Foreground service that mirrors the shared [MpdConnectionManager] into an OS
- * [MediaSessionCompat]: it publishes now-playing metadata + playback state
+ * [MediaSessionCompat]: it publishes now-playing metadata + playback state (driving the media
- * (driving the media notification, lock screen, and Quick Settings player),
+ * notification, lock screen, and Quick Settings player), exposes transport controls, and — via
- * exposes transport controls, and — via [setPlaybackToRemote] with a
+ * [setPlaybackToRemote] with a [VolumeProviderCompat] — makes the hardware volume keys control the
- * [VolumeProviderCompat] — makes the hardware volume keys control the *server's*
+ * *server's* volume system-wide, cast-style, even when the app is in the background.
- * volume system-wide, cast-style, even when the app is in the background.
  *
  * Started/stopped by [MpdConnectionManager] as the connection comes and goes.
  */
 class PlaybackService : Service() {
-
     private val scope = CoroutineScope(SupervisorJob() + Dispatchers.Main.immediate)
-    private val manager get() = (application as EncoreApplication).manager
+    private val manager
+        get() = (application as EncoreApplication).manager
 
     private lateinit var session: MediaSessionCompat
     private lateinit var volumeProvider: VolumeProviderCompat
@@ -62,13 +61,16 @@ class PlaybackService : Service() {
     override fun onCreate() {
         super.onCreate()
 
-        session = MediaSessionCompat(this, "Encore").apply {
+        session =
+            MediaSessionCompat(this, "Encore").apply {
                 setCallback(mediaCallback)
                 isActive = true
             }
 
         // Remote (cast-style) volume: absolute 0..100, initialised from the server.
-        volumeProvider = object : VolumeProviderCompat(
+        volumeProvider =
+            object :
+                VolumeProviderCompat(
                     VOLUME_CONTROL_ABSOLUTE,
                     MAX_VOLUME,
                     manager.status.value?.volume ?: 0,
@@ -88,7 +90,11 @@ class PlaybackService : Service() {
         observeState()
     }
 
-    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
+    override fun onStartCommand(
+        intent: Intent?,
+        flags: Int,
+        startId: Int,
+    ): Int {
         // Deliver hardware / notification media-button presses to the session.
         MediaButtonReceiver.handleIntent(session, intent)
         startForeground(NOTIFICATION_ID, buildNotification())
@@ -102,12 +108,18 @@ class PlaybackService : Service() {
         super.onDestroy()
     }
 
-    private val mediaCallback = object : MediaSessionCompat.Callback() {
+    private val mediaCallback =
+        object : MediaSessionCompat.Callback() {
             override fun onPlay() = manager.resume()
+
             override fun onPause() = manager.pause()
+
             override fun onStop() = manager.stop()
+
             override fun onSkipToNext() = manager.next()
+
             override fun onSkipToPrevious() = manager.previous()
+
             override fun onSeekTo(pos: Long) = manager.seekTo(pos / 1000.0)
         }
 
@@ -135,7 +147,9 @@ class PlaybackService : Service() {
                     artUri = uri
                     artBitmap = if (uri != null) loadArtBitmap(uri) else null
                     if (artUri == uri) {
-                        session.setMetadata(buildMetadata(manager.currentSong.value, manager.status.value))
+                        session.setMetadata(
+                            buildMetadata(manager.currentSong.value, manager.status.value)
+                        )
                         postNotification()
                     }
                 }
@@ -151,14 +165,18 @@ class PlaybackService : Service() {
     }
 
     private suspend fun loadArtBitmap(uri: String): Bitmap? {
-        val result = SingletonImageLoader.get(applicationContext).execute(
+        val result =
-            ImageRequest.Builder(applicationContext).data(SongArt(uri)).build(),
+            SingletonImageLoader.get(applicationContext)
-        )
+                .execute(ImageRequest.Builder(applicationContext).data(SongArt(uri)).build())
         return (result as? SuccessResult)?.image?.toBitmap()
     }
 
-    private fun buildMetadata(song: MpdSong?, status: MpdStatus?): MediaMetadataCompat =
+    private fun buildMetadata(
-        MediaMetadataCompat.Builder().apply {
+        song: MpdSong?,
+        status: MpdStatus?,
+    ): MediaMetadataCompat =
+        MediaMetadataCompat.Builder()
+            .apply {
                 putString(MediaMetadataCompat.METADATA_KEY_TITLE, song?.title ?: song?.uri ?: "")
                 putString(MediaMetadataCompat.METADATA_KEY_ARTIST, song?.artist ?: "")
                 putString(MediaMetadataCompat.METADATA_KEY_ALBUM, song?.album ?: "")
@@ -167,10 +185,12 @@ class PlaybackService : Service() {
                 if (artBitmap != null && artUri == song?.uri) {
                     putBitmap(MediaMetadataCompat.METADATA_KEY_ALBUM_ART, artBitmap)
                 }
-        }.build()
+            }
+            .build()
 
     private fun buildPlaybackState(status: MpdStatus?): PlaybackStateCompat {
-        val state = when (status?.state) {
+        val state =
+            when (status?.state) {
                 PlayerState.PLAY -> PlaybackStateCompat.STATE_PLAYING
                 PlayerState.PAUSE -> PlaybackStateCompat.STATE_PAUSED
                 else -> PlaybackStateCompat.STATE_STOPPED
@@ -185,7 +205,7 @@ class PlaybackService : Service() {
                     PlaybackStateCompat.ACTION_SKIP_TO_NEXT or
                     PlaybackStateCompat.ACTION_SKIP_TO_PREVIOUS or
                     PlaybackStateCompat.ACTION_SEEK_TO or
-                    PlaybackStateCompat.ACTION_STOP,
+                    PlaybackStateCompat.ACTION_STOP
             )
             .setState(state, positionMs, speed)
             .build()
@@ -195,24 +215,32 @@ class PlaybackService : Service() {
         val song = manager.currentSong.value
         val playing = manager.status.value?.state == PlayerState.PLAY
 
-        val contentIntent = PendingIntent.getActivity(
+        val contentIntent =
+            PendingIntent.getActivity(
                 this,
                 0,
                 Intent(this, MainActivity::class.java),
                 PendingIntent.FLAG_IMMUTABLE or PendingIntent.FLAG_UPDATE_CURRENT,
             )
 
-        val playPause = if (playing) {
+        val playPause =
+            if (playing) {
                 NotificationCompat.Action(
                     android.R.drawable.ic_media_pause,
                     "Pause",
-                MediaButtonReceiver.buildMediaButtonPendingIntent(this, PlaybackStateCompat.ACTION_PLAY_PAUSE),
+                    MediaButtonReceiver.buildMediaButtonPendingIntent(
+                        this,
+                        PlaybackStateCompat.ACTION_PLAY_PAUSE,
+                    ),
                 )
             } else {
                 NotificationCompat.Action(
                     android.R.drawable.ic_media_play,
                     "Play",
-                MediaButtonReceiver.buildMediaButtonPendingIntent(this, PlaybackStateCompat.ACTION_PLAY_PAUSE),
+                    MediaButtonReceiver.buildMediaButtonPendingIntent(
+                        this,
+                        PlaybackStateCompat.ACTION_PLAY_PAUSE,
+                    ),
                 )
             }
 
@@ -227,18 +255,24 @@ class PlaybackService : Service() {
             .addAction(
                 android.R.drawable.ic_media_previous,
                 "Previous",
-                MediaButtonReceiver.buildMediaButtonPendingIntent(this, PlaybackStateCompat.ACTION_SKIP_TO_PREVIOUS),
+                MediaButtonReceiver.buildMediaButtonPendingIntent(
+                    this,
+                    PlaybackStateCompat.ACTION_SKIP_TO_PREVIOUS,
+                ),
             )
             .addAction(playPause)
             .addAction(
                 android.R.drawable.ic_media_next,
                 "Next",
-                MediaButtonReceiver.buildMediaButtonPendingIntent(this, PlaybackStateCompat.ACTION_SKIP_TO_NEXT),
+                MediaButtonReceiver.buildMediaButtonPendingIntent(
+                    this,
+                    PlaybackStateCompat.ACTION_SKIP_TO_NEXT,
+                ),
             )
             .setStyle(
                 MediaStyle()
                     .setMediaSession(session.sessionToken)
-                    .setShowActionsInCompactView(0, 1, 2),
+                    .setShowActionsInCompactView(0, 1, 2)
             )
             .build()
     }
@@ -250,11 +284,13 @@ class PlaybackService : Service() {
 
     private fun createChannel() {
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
-            val channel = NotificationChannel(
+            val channel =
+                NotificationChannel(
                         CHANNEL_ID,
                         "Playback",
                         NotificationManager.IMPORTANCE_LOW,
-            ).apply {
+                    )
+                    .apply {
                         description = "Now-playing controls"
                         setShowBadge(false)
                     }

app/src/main/kotlin/ca/ksamad/encore/playback/VolumeKeyDispatcher.kt

@@ -5,28 +5,26 @@ import android.view.KeyEvent
 /**
  * Encapsulates hardware volume-key handling for the foreground Activity.
  *
- * While the app is focused, we want the volume keys to drive the *server*
+ * While the app is focused, we want the volume keys to drive the *server* volume **silently** —
- * volume **silently** — without the system's volume slider popping up (the app
+ * without the system's volume slider popping up (the app already shows its own). The trick is to
- * already shows its own). The trick is to fully consume the key event in the
+ * fully consume the key event in the Activity so it never reaches the OS volume handling that draws
- * Activity so it never reaches the OS volume handling that draws that slider.
+ * that slider.
  *
- * When the app is backgrounded the Activity isn't in the dispatch path at all,
+ * When the app is backgrounded the Activity isn't in the dispatch path at all, so the
- * so the `MediaSession`'s `VolumeProvider` handles the keys instead — there the
+ * `MediaSession`'s `VolumeProvider` handles the keys instead — there the OS remote-volume UI
- * OS remote-volume UI showing up is the expected, cast-style behaviour.
+ * showing up is the expected, cast-style behaviour.
  *
- * Only volume keys we actually act on are consumed: when we're not controlling
+ * Only volume keys we actually act on are consumed: when we're not controlling the server (e.g. the
- * the server (e.g. the connect screen), the event passes through so the device
+ * connect screen), the event passes through so the device adjusts its own local volume normally.
- * adjusts its own local volume normally.
  */
 class VolumeKeyDispatcher(private val manager: MpdConnectionManager) {
-
     /**
-     * Offer [event] to the volume handler. Returns `true` if it was a volume key
+     * Offer [event] to the volume handler. Returns `true` if it was a volume key we handled and
-     * we handled and consumed (caller should then *not* pass it on), `false` to
+     * consumed (caller should then *not* pass it on), `false` to let normal dispatch continue.
-     * let normal dispatch continue.
      */
     fun dispatch(event: KeyEvent): Boolean {
-        val up = when (event.keyCode) {
+        val up =
+            when (event.keyCode) {
                 KeyEvent.KEYCODE_VOLUME_UP -> true
                 KeyEvent.KEYCODE_VOLUME_DOWN -> false
                 else -> return false

app/src/main/kotlin/ca/ksamad/encore/ui/AlbumDetailScreen.kt

@@ -46,10 +46,10 @@ import ca.ksamad.encore.playback.AlbumArt
 import kotlinx.coroutines.launch
 
 /**
- * One album, in detail: its cover, whole-album Play / Add-to-queue actions, and
+ * One album, in detail: its cover, whole-album Play / Add-to-queue actions, and the track list.
- * the track list. Tapping Play replaces the queue and starts the album (leaving
+ * Tapping Play replaces the queue and starts the album (leaving this screen); swiping a track
- * this screen); swiping a track queues it (right) or plays it next (left), with
+ * queues it (right) or plays it next (left), with the same semantics as swiping an album in the
- * the same semantics as swiping an album in the library.
+ * library.
  */
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
@@ -60,12 +60,14 @@ fun AlbumDetailScreen(
     onPlay: () -> Unit,
 ) {
     // null = still loading the track list.
-    val tracks by produceState<List<MpdSong>?>(initialValue = null, album) {
+    val tracks by
+        produceState<List<MpdSong>?>(initialValue = null, album) {
             value = vm.loadAlbumTracks(album.name, album.albumArtist)
         }
 
     val snackbarHostState = remember { SnackbarHostState() }
     val scope = rememberCoroutineScope()
+
     fun flash(message: String) {
         snackbarHostState.currentSnackbarData?.dismiss()
         scope.launch { snackbarHostState.showSnackbar(message) }
@@ -117,14 +119,19 @@ fun AlbumDetailScreen(
 
             val loaded = tracks
             when {
-                loaded == null -> item {
+                loaded == null -> {
+                    item {
                         Box(
                             Modifier.fillMaxWidth().padding(32.dp),
                             contentAlignment = Alignment.Center,
-                    ) { CircularProgressIndicator() }
+                        ) {
+                            CircularProgressIndicator()
+                        }
+                    }
                 }
 
-                loaded.isEmpty() -> item {
+                loaded.isEmpty() -> {
+                    item {
                         Box(
                             Modifier.fillMaxWidth().padding(32.dp),
                             contentAlignment = Alignment.Center,
@@ -135,20 +142,24 @@ fun AlbumDetailScreen(
                             )
                         }
                     }
+                }
 
                 // Single disc (or untagged): a plain flat list.
-                loaded.map(::discNumberOf).distinct().size <= 1 ->
+                loaded.map(::discNumberOf).distinct().size <= 1 -> {
                     items(loaded, key = { it.uri }) { trackItem(it) }
+                }
 
                 // Multi-disc: a light "Disc N" header before each disc's tracks. The
                 // list arrives already sorted by (disc, track), so groupBy keeps order.
-                else -> loaded.groupBy(::discNumberOf).forEach { (disc, discTracks) ->
+                else -> {
+                    loaded.groupBy(::discNumberOf).forEach { (disc, discTracks) ->
                         item(key = "disc-$disc") { DiscHeader(disc) }
                         items(discTracks, key = { it.uri }) { trackItem(it) }
                     }
                 }
             }
         }
+    }
 }
 
 /** Cover, title/artist, and the two whole-album action buttons. */
@@ -201,10 +212,9 @@ private fun AlbumDetailHeader(
 }
 
 /**
- * A single track row. Swiping right queues the track, swiping left plays it next
+ * A single track row. Swiping right queues the track, swiping left plays it next — the same gesture
- * — the same gesture as the album library, scoped to this one track. The leading
+ * as the album library, scoped to this one track. The leading slot shows the track number (all
- * slot shows the track number (all tracks share the album's cover, so a per-track
+ * tracks share the album's cover, so a per-track thumbnail would be redundant here).
- * thumbnail would be redundant here).
  */
 @Composable
 private fun TrackRow(
@@ -226,7 +236,8 @@ private fun TrackRow(
             headlineContent = {
                 Text(track.title ?: track.uri, maxLines = 1, overflow = TextOverflow.Ellipsis)
             },
-            supportingContent = track.artist?.let {
+            supportingContent =
+                track.artist?.let {
                     { Text(it, maxLines = 1, overflow = TextOverflow.Ellipsis) }
                 },
             trailingContent = track.duration?.let { { Text(formatDuration(it)) } },

app/src/main/kotlin/ca/ksamad/encore/ui/AlbumsScreen.kt

@@ -52,16 +52,23 @@ import ca.ksamad.encore.playback.AlbumArt
 import kotlinx.coroutines.launch
 
 /**
- * Browse every album on the server. Tapping one opens its detail screen; swiping
+ * Browse every album on the server. Tapping one opens its detail screen; swiping a row queues the
- * a row queues the whole album (right) or plays it next (left).
+ * whole album (right) or plays it next (left).
  */
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
-fun AlbumsScreen(vm: PlayerViewModel, onBack: () -> Unit, onOpenAlbum: (MpdAlbum) -> Unit) {
+fun AlbumsScreen(
+    vm: PlayerViewModel,
+    onBack: () -> Unit,
+    onOpenAlbum: (MpdAlbum) -> Unit,
+) {
     // null = still loading.
-    val albums by produceState<List<MpdAlbum>?>(initialValue = null) {
+    val albums by
-        value = vm.loadAlbums().sortedWith(
+        produceState<List<MpdAlbum>?>(initialValue = null) {
-            compareBy({ it.albumArtist?.lowercase() ?: "" }, { it.name.lowercase() }),
+            value =
+                vm.loadAlbums()
+                    .sortedWith(
+                        compareBy({ it.albumArtist?.lowercase() ?: "" }, { it.name.lowercase() })
                     )
         }
 
@@ -72,6 +79,7 @@ fun AlbumsScreen(vm: PlayerViewModel, onBack: () -> Unit, onOpenAlbum: (MpdAlbum
     // Transient confirmation for the swipe actions (add-to-queue / play-next).
     val snackbarHostState = remember { SnackbarHostState() }
     val scope = rememberCoroutineScope()
+
     fun flash(message: String) {
         // Replace any in-flight snackbar so rapid swipes feel snappy, not queued.
         snackbarHostState.currentSnackbarData?.dismiss()
@@ -79,20 +87,29 @@ fun AlbumsScreen(vm: PlayerViewModel, onBack: () -> Unit, onOpenAlbum: (MpdAlbum
     }
 
     val current = albums
-    val filtered = remember(current, query) {
+    val filtered =
+        remember(current, query) {
             // Match every whitespace-separated term against the album title + artist
             // together, so a query can span both fields ("beatles abbey") and word
             // order doesn't matter.
             val terms = query.trim().lowercase().split(Regex("\\s+")).filter { it.isNotEmpty() }
             when {
-            current == null -> null
+                current == null -> {
-            terms.isEmpty() -> current
+                    null
-            else -> current.filter { album ->
+                }
+
+                terms.isEmpty() -> {
+                    current
+                }
+
+                else -> {
+                    current.filter { album ->
                         val haystack = "${album.name} ${album.albumArtist ?: ""}".lowercase()
                         terms.all { haystack.contains(it) }
                     }
                 }
             }
+        }
 
     Scaffold(
         topBar = {
@@ -105,14 +122,16 @@ fun AlbumsScreen(vm: PlayerViewModel, onBack: () -> Unit, onOpenAlbum: (MpdAlbum
                     }
                 },
                 navigationIcon = {
-                    IconButton(onClick = {
+                    IconButton(
+                        onClick = {
                             if (searching) {
                                 searching = false
                                 query = ""
                             } else {
                                 onBack()
                             }
-                    }) {
+                        }
+                    ) {
                         Icon(Icons.AutoMirrored.Filled.ArrowBack, contentDescription = "Back")
                     }
                 },
@@ -132,22 +151,30 @@ fun AlbumsScreen(vm: PlayerViewModel, onBack: () -> Unit, onOpenAlbum: (MpdAlbum
         snackbarHost = { SnackbarHost(snackbarHostState) },
     ) { innerPadding ->
         when {
-            filtered == null -> Box(
+            filtered == null -> {
+                Box(
                     Modifier.fillMaxSize().padding(innerPadding),
                     contentAlignment = Alignment.Center,
-            ) { CircularProgressIndicator() }
+                ) {
+                    CircularProgressIndicator()
+                }
+            }
 
-            filtered.isEmpty() -> Box(
+            filtered.isEmpty() -> {
+                Box(
                     Modifier.fillMaxSize().padding(innerPadding),
                     contentAlignment = Alignment.Center,
                 ) {
                     Text(
-                    if (query.isBlank()) "No albums found" else "No albums match \"${query.trim()}\"",
+                        if (query.isBlank()) "No albums found"
+                        else "No albums match \"${query.trim()}\"",
                         color = MaterialTheme.colorScheme.onSurfaceVariant,
                     )
                 }
+            }
 
-            else -> LazyColumn(modifier = Modifier.padding(innerPadding)) {
+            else -> {
+                LazyColumn(modifier = Modifier.padding(innerPadding)) {
                     items(filtered, key = { "${it.name} ${it.albumArtist}" }) { album ->
                         SwipeableAlbumRow(
                             album = album,
@@ -165,12 +192,13 @@ fun AlbumsScreen(vm: PlayerViewModel, onBack: () -> Unit, onOpenAlbum: (MpdAlbum
                 }
             }
         }
+    }
 }
 
 /**
- * One album row. Tapping opens the album ([onTap]); swiping reveals two one-shot
+ * One album row. Tapping opens the album ([onTap]); swiping reveals two one-shot actions that leave
- * actions that leave the row in place — right ([onQueue]) appends the album to the
+ * the row in place — right ([onQueue]) appends the album to the queue, left ([onPlayNext]) inserts
- * queue, left ([onPlayNext]) inserts it right after the current track.
+ * it right after the current track.
  */
 @Composable
 private fun SwipeableAlbumRow(
@@ -186,15 +214,14 @@ private fun SwipeableAlbumRow(
                 ArtImage(
                     model = AlbumArt(album.name, album.albumArtist),
                     iconSize = 24.dp,
-                    modifier = Modifier
+                    modifier = Modifier.size(48.dp).clip(RoundedCornerShape(6.dp)),
-                        .size(48.dp)
-                        .clip(RoundedCornerShape(6.dp)),
                 )
             },
             headlineContent = {
                 Text(album.name, maxLines = 1, overflow = TextOverflow.Ellipsis)
             },
-            supportingContent = album.albumArtist?.let {
+            supportingContent =
+                album.albumArtist?.let {
                     { Text(it, maxLines = 1, overflow = TextOverflow.Ellipsis) }
                 },
         )
@@ -202,12 +229,15 @@ private fun SwipeableAlbumRow(
 }
 
 /**
- * Inline search box that lives in the top bar while searching. Auto-focuses and
+ * Inline search box that lives in the top bar while searching. Auto-focuses and opens the keyboard;
- * opens the keyboard; the surrounding [TopAppBar] handles clearing/closing.
+ * the surrounding [TopAppBar] handles clearing/closing.
  */
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
-private fun AlbumSearchField(query: String, onQueryChange: (String) -> Unit) {
+private fun AlbumSearchField(
+    query: String,
+    onQueryChange: (String) -> Unit,
+) {
     val focusRequester = remember { FocusRequester() }
     val focusManager = LocalFocusManager.current
 
@@ -220,7 +250,8 @@ private fun AlbumSearchField(query: String, onQueryChange: (String) -> Unit) {
         placeholder = { Text("Search albums & artists") },
         keyboardOptions = KeyboardOptions(imeAction = ImeAction.Search),
         keyboardActions = KeyboardActions(onSearch = { focusManager.clearFocus() }),
-        colors = TextFieldDefaults.colors(
+        colors =
+            TextFieldDefaults.colors(
                 focusedContainerColor = Color.Transparent,
                 unfocusedContainerColor = Color.Transparent,
                 focusedIndicatorColor = Color.Transparent,

app/src/main/kotlin/ca/ksamad/encore/ui/ArtImage.kt

@@ -16,13 +16,17 @@ import androidx.compose.ui.unit.Dp
 import coil3.compose.AsyncImage
 
 /**
- * Cover art with a disc-icon placeholder. Draws the placeholder underneath and
+ * Cover art with a disc-icon placeholder. Draws the placeholder underneath and lets the
- * lets the [AsyncImage] paint over it once (and if) art loads — so a missing
+ * [AsyncImage] paint over it once (and if) art loads — so a missing cover, a still-loading fetch,
- * cover, a still-loading fetch, and a solid image all look right. [model] is an
+ * and a solid image all look right. [model] is an [ca.ksamad.encore.playback.MpdArtData] (or null
- * [ca.ksamad.encore.playback.MpdArtData] (or null to show just the placeholder).
+ * to show just the placeholder).
  */
 @Composable
-fun ArtImage(model: Any?, iconSize: Dp, modifier: Modifier = Modifier) {
+fun ArtImage(
+    model: Any?,
+    iconSize: Dp,
+    modifier: Modifier = Modifier,
+) {
     Box(
         modifier = modifier.background(MaterialTheme.colorScheme.surfaceVariant),
         contentAlignment = Alignment.Center,

app/src/main/kotlin/ca/ksamad/encore/ui/EncoreApp.kt

@@ -29,18 +29,25 @@ import ca.ksamad.encore.data.ConnectionSettings
 import ca.ksamad.encore.mpd.model.MpdAlbum
 
 /**
- * App root. Renders whichever [AppScreen] the [PlayerViewModel] decides on: a
+ * App root. Renders whichever [AppScreen] the [PlayerViewModel] decides on: a brief loading splash
- * brief loading splash while it reads settings / auto-connects, the connect form
+ * while it reads settings / auto-connects, the connect form (first run, after disconnect, or on
- * (first run, after disconnect, or on error), or the now-playing screen.
+ * error), or the now-playing screen.
  */
+
 /** Sub-screens layered over the player (no nav library needed for this few). */
-private enum class PlayerOverlay { None, Settings, Albums, Queue }
+private enum class PlayerOverlay {
+    None,
+    Settings,
+    Albums,
+    Queue,
+}
 
 /** Saves the drilled-into album (name + artist) across config change/process death. */
-private val AlbumSaver = listSaver<MpdAlbum?, String?>(
+private val AlbumSaver =
+    listSaver<MpdAlbum?, String?>(
         save = { listOf(it?.name, it?.albumArtist) },
         restore = { saved -> saved[0]?.let { name -> MpdAlbum(name, saved[1]) } },
-)
+    )
 
 @Composable
 fun EncoreApp(vm: PlayerViewModel = viewModel()) {
@@ -59,10 +66,20 @@ fun EncoreApp(vm: PlayerViewModel = viewModel()) {
     }
 
     when (val s = screen) {
-        is AppScreen.Loading -> LoadingScreen()
+        is AppScreen.Loading -> {
-        is AppScreen.Connect -> ConnectScreen(vm, s.settings, s.error)
+            LoadingScreen()
-        is AppScreen.Player -> when (overlay) {
+        }
-            PlayerOverlay.Settings -> SettingsScreen(vm, onBack = { overlay = PlayerOverlay.None })
+
+        is AppScreen.Connect -> {
+            ConnectScreen(vm, s.settings, s.error)
+        }
+
+        is AppScreen.Player -> {
+            when (overlay) {
+                PlayerOverlay.Settings -> {
+                    SettingsScreen(vm, onBack = { overlay = PlayerOverlay.None })
+                }
+
                 PlayerOverlay.Albums -> {
                     val selected = detailAlbum
                     if (selected != null) {
@@ -83,8 +100,13 @@ fun EncoreApp(vm: PlayerViewModel = viewModel()) {
                         )
                     }
                 }
-            PlayerOverlay.Queue -> QueueScreen(vm, onBack = { overlay = PlayerOverlay.None })
+
-            PlayerOverlay.None -> NowPlayingScreen(
+                PlayerOverlay.Queue -> {
+                    QueueScreen(vm, onBack = { overlay = PlayerOverlay.None })
+                }
+
+                PlayerOverlay.None -> {
+                    NowPlayingScreen(
                         vm,
                         onOpenSettings = { overlay = PlayerOverlay.Settings },
                         onOpenLibrary = { overlay = PlayerOverlay.Albums },
@@ -92,6 +114,8 @@ fun EncoreApp(vm: PlayerViewModel = viewModel()) {
                     )
                 }
             }
+        }
+    }
 }
 
 @Composable
@@ -111,7 +135,11 @@ private fun LoadingScreen() {
 }
 
 @Composable
-private fun ConnectScreen(vm: PlayerViewModel, saved: ConnectionSettings, error: String?) {
+private fun ConnectScreen(
+    vm: PlayerViewModel,
+    saved: ConnectionSettings,
+    error: String?,
+) {
     // Seed the fields from the persisted settings. Keyed on the loaded values so
     // the form re-seeds once DataStore delivers them, but a user's edits after
     // that stick (rememberSaveable also survives rotation/process death).
@@ -119,9 +147,7 @@ private fun ConnectScreen(vm: PlayerViewModel, saved: ConnectionSettings, error:
     var port by rememberSaveable(saved.port) { mutableStateOf(saved.port.toString()) }
 
     Column(
-        modifier = Modifier
+        modifier = Modifier.fillMaxSize().padding(24.dp),
-            .fillMaxSize()
-            .padding(24.dp),
         horizontalAlignment = Alignment.CenterHorizontally,
         verticalArrangement = Arrangement.Center,
     ) {
@@ -145,8 +171,9 @@ private fun ConnectScreen(vm: PlayerViewModel, saved: ConnectionSettings, error:
             onValueChange = { port = it.filter(Char::isDigit) },
             label = { Text("Port") },
             singleLine = true,
-            keyboardOptions = androidx.compose.foundation.text.KeyboardOptions(
+            keyboardOptions =
-                keyboardType = KeyboardType.Number,
+                androidx.compose.foundation.text.KeyboardOptions(
+                    keyboardType = KeyboardType.Number
                 ),
             modifier = Modifier.fillMaxWidth(),
         )

app/src/main/kotlin/ca/ksamad/encore/ui/NowPlayingScreen.kt

@@ -1,8 +1,6 @@
 package ca.ksamad.encore.ui
 
 import androidx.compose.foundation.background
-import androidx.compose.foundation.rememberScrollState
-import androidx.compose.foundation.verticalScroll
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.ExperimentalLayoutApi
@@ -14,7 +12,9 @@ import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.rememberScrollState
 import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.foundation.verticalScroll
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.automirrored.filled.QueueMusic
 import androidx.compose.material.icons.filled.Cast
@@ -22,8 +22,8 @@ import androidx.compose.material.icons.filled.LibraryMusic
 import androidx.compose.material.icons.filled.Pause
 import androidx.compose.material.icons.filled.PlayArrow
 import androidx.compose.material.icons.filled.Repeat
-import androidx.compose.material.icons.filled.Shuffle
 import androidx.compose.material.icons.filled.Settings
+import androidx.compose.material.icons.filled.Shuffle
 import androidx.compose.material.icons.filled.SkipNext
 import androidx.compose.material.icons.filled.SkipPrevious
 import androidx.compose.material.icons.filled.VolumeUp
@@ -50,15 +50,14 @@ import androidx.compose.ui.text.style.TextOverflow
 import androidx.compose.ui.unit.dp
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import ca.ksamad.encore.mpd.model.MpdStatus
-import ca.ksamad.encore.playback.SongArt
 import ca.ksamad.encore.mpd.model.PlayerState
+import ca.ksamad.encore.playback.SongArt
 import kotlinx.coroutines.delay
 
 /**
- * The now-playing screen: current track, a live seek bar, transport controls,
+ * The now-playing screen: current track, a live seek bar, transport controls, volume, and the
- * volume, and the repeat/random toggles. Everything reads from the
+ * repeat/random toggles. Everything reads from the [PlayerViewModel] flows, so it updates whenever
- * [PlayerViewModel] flows, so it updates whenever the server pushes a change —
+ * the server pushes a change — including changes made from other clients.
- * including changes made from other clients.
  */
 @Composable
 fun NowPlayingScreen(
@@ -72,10 +71,7 @@ fun NowPlayingScreen(
     val serverHost by vm.serverHost.collectAsStateWithLifecycle()
 
     Column(
-        modifier = Modifier
+        modifier = Modifier.fillMaxSize().verticalScroll(rememberScrollState()).padding(24.dp),
-            .fillMaxSize()
-            .verticalScroll(rememberScrollState())
-            .padding(24.dp),
         horizontalAlignment = Alignment.CenterHorizontally,
     ) {
         // --- Top bar: library + settings ------------------------------------
@@ -95,10 +91,8 @@ fun NowPlayingScreen(
         ArtImage(
             model = song?.uri?.let { SongArt(it) },
             iconSize = 96.dp,
-            modifier = Modifier
+            modifier =
-                .padding(vertical = 16.dp)
+                Modifier.padding(vertical = 16.dp).size(240.dp).clip(RoundedCornerShape(16.dp)),
-                .size(240.dp)
-                .clip(RoundedCornerShape(16.dp)),
         )
 
         // --- Track metadata --------------------------------------------------
@@ -126,7 +120,8 @@ fun NowPlayingScreen(
         )
 
         // Descriptive metadata (release year · genre), when the tags are present.
-        val descriptors = listOfNotNull(
+        val descriptors =
+            listOfNotNull(
                 song?.date?.let(::releaseYear),
                 song?.genre?.takeIf { it.isNotBlank() },
             )
@@ -222,18 +217,21 @@ fun NowPlayingScreen(
 }
 
 /**
- * Seek bar that ticks locally between server updates. MPD only pushes a change
+ * Seek bar that ticks locally between server updates. MPD only pushes a change event on discrete
- * event on discrete events (play/pause/seek/song change), not once per second,
+ * events (play/pause/seek/song change), not once per second, so we advance [MpdStatus.elapsed]
- * so we advance [MpdStatus.elapsed] locally while playing to keep the bar
+ * locally while playing to keep the bar moving, resyncing whenever a fresh status arrives.
- * moving, resyncing whenever a fresh status arrives.
  */
 @Composable
-private fun SeekBar(status: MpdStatus?, onSeek: (Double) -> Unit) {
+private fun SeekBar(
+    status: MpdStatus?,
+    onSeek: (Double) -> Unit,
+) {
     val duration = status?.duration ?: 0.0
     val playing = status?.state == PlayerState.PLAY
 
     // Local playback position, reseeded on every new status snapshot.
-    var position by remember(status?.songId, status?.elapsed, status?.state) {
+    var position by
+        remember(status?.songId, status?.elapsed, status?.state) {
             mutableFloatStateOf((status?.elapsed ?: 0.0).toFloat())
         }
     var dragValue by remember { mutableStateOf<Float?>(null) }
@@ -266,9 +264,9 @@ private fun SeekBar(status: MpdStatus?, onSeek: (Double) -> Unit) {
 }
 
 /**
- * Little pills describing the current stream's audio format — sample rate, bit
+ * Little pills describing the current stream's audio format — sample rate, bit depth, channels, and
- * depth, channels, and (live) bitrate — derived from MPD's `audio`/`bitrate`
+ * (live) bitrate — derived from MPD's `audio`/`bitrate` status fields. Renders nothing when there's
- * status fields. Renders nothing when there's no format info (e.g. stopped).
+ * no format info (e.g. stopped).
  */
 @OptIn(ExperimentalLayoutApi::class)
 @Composable
@@ -277,9 +275,7 @@ private fun AudioPropertyPills(status: MpdStatus?) {
     if (pills.isEmpty()) return
 
     FlowRow(
-        modifier = Modifier
+        modifier = Modifier.fillMaxWidth().padding(top = 10.dp),
-            .fillMaxWidth()
-            .padding(top = 10.dp),
         horizontalArrangement = Arrangement.spacedBy(6.dp, Alignment.CenterHorizontally),
         verticalArrangement = Arrangement.spacedBy(6.dp),
     ) {
@@ -288,8 +284,8 @@ private fun AudioPropertyPills(status: MpdStatus?) {
                 text = pill,
                 style = MaterialTheme.typography.labelSmall,
                 color = MaterialTheme.colorScheme.onSecondaryContainer,
-                modifier = Modifier
+                modifier =
-                    .clip(RoundedCornerShape(50))
+                    Modifier.clip(RoundedCornerShape(50))
                         .background(MaterialTheme.colorScheme.secondaryContainer)
                         .padding(horizontal = 10.dp, vertical = 4.dp),
             )
@@ -298,15 +294,18 @@ private fun AudioPropertyPills(status: MpdStatus?) {
 }
 
 /**
- * Build the audio-format pill labels from a status snapshot. MPD's `audio` field
+ * Build the audio-format pill labels from a status snapshot. MPD's `audio` field is
- * is `samplerate:bits:channels` (e.g. `"44100:16:2"`), where the middle token can
+ * `samplerate:bits:channels` (e.g. `"44100:16:2"`), where the middle token can be `f` (float) or
- * be `f` (float) or `dsd` rather than a bit depth. Only well-formed parts appear.
+ * `dsd` rather than a bit depth. Only well-formed parts appear.
  */
 private fun audioPropertyPills(status: MpdStatus?): List<String> {
     status ?: return emptyList()
     val pills = mutableListOf<String>()
 
-    status.audio?.split(":")?.takeIf { it.size >= 3 }?.let { parts ->
+    status.audio
+        ?.split(":")
+        ?.takeIf { it.size >= 3 }
+        ?.let { parts ->
             parts[0].toIntOrNull()?.let { pills.add(formatSampleRate(it)) }
             formatSampleFormat(parts[1])?.let { pills.add(it) }
             formatChannels(parts[2])?.let { pills.add(it) }
@@ -322,27 +321,27 @@ private fun formatSampleRate(hz: Int): String {
     return "$value kHz"
 }
 
-private fun formatSampleFormat(token: String): String? = when (token) {
+private fun formatSampleFormat(token: String): String? =
+    when (token) {
         "f" -> "Float"
         "dsd" -> "DSD"
         else -> token.toIntOrNull()?.let { "$it-bit" }
-}
+    }
 
-private fun formatChannels(token: String): String? = when (token.toIntOrNull()) {
+private fun formatChannels(token: String): String? =
+    when (token.toIntOrNull()) {
         null -> null
         1 -> "Mono"
         2 -> "Stereo"
         else -> "$token ch"
-}
+    }
 
 /** "Casting" affordance: signals that the volume below controls the server, not the device. */
 @Composable
 private fun CastIndicator(host: String?) {
     if (host == null) return
     Row(
-        modifier = Modifier
+        modifier = Modifier.fillMaxWidth().padding(bottom = 4.dp),
-            .fillMaxWidth()
-            .padding(bottom = 4.dp),
         verticalAlignment = Alignment.CenterVertically,
         horizontalArrangement = Arrangement.Center,
     ) {
@@ -362,7 +361,10 @@ private fun CastIndicator(host: String?) {
 }
 
 @Composable
-private fun VolumeControl(volume: Int?, onSetVolume: (Int) -> Unit) {
+private fun VolumeControl(
+    volume: Int?,
+    onSetVolume: (Int) -> Unit,
+) {
     // Local thumb position seeded from the server; committed on release.
     var dragValue by remember(volume) { mutableStateOf<Float?>(null) }
     val enabled = volume != null
@@ -383,9 +385,7 @@ private fun VolumeControl(volume: Int?, onSetVolume: (Int) -> Unit) {
             },
             valueRange = 0f..100f,
             enabled = enabled,
-            modifier = Modifier
+            modifier = Modifier.weight(1f).padding(horizontal = 12.dp),
-                .weight(1f)
-                .padding(horizontal = 12.dp),
         )
         Text(
             text = if (enabled) "${shown.toInt()}" else "—",
@@ -397,8 +397,7 @@ private fun VolumeControl(volume: Int?, onSetVolume: (Int) -> Unit) {
 }
 
 /** The 4-digit year from an MPD `Date` tag (`"2019"`, `"2019-05-03"`, …), or null. */
-private fun releaseYear(date: String): String? =
+private fun releaseYear(date: String): String? = Regex("\\d{4}").find(date)?.value
-    Regex("\\d{4}").find(date)?.value
 
 private fun formatTime(seconds: Double): String {
     val total = seconds.toInt().coerceAtLeast(0)

app/src/main/kotlin/ca/ksamad/encore/ui/PlayerViewModel.kt

@@ -17,21 +17,22 @@ sealed interface AppScreen {
     data object Loading : AppScreen
 
     /** First run, after a disconnect, or a failed connection. */
-    data class Connect(val settings: ConnectionSettings, val error: String?) : AppScreen
+    data class Connect(
+        val settings: ConnectionSettings,
+        val error: String?,
+    ) : AppScreen
 
     /** Connected: show playback. */
     data object Player : AppScreen
 }
 
 /**
- * Thin UI-facing layer over the app-scoped
+ * Thin UI-facing layer over the app-scoped [ca.ksamad.encore.playback.MpdConnectionManager]: it
- * [ca.ksamad.encore.playback.MpdConnectionManager]: it exposes the manager's
+ * exposes the manager's flows to Compose and derives the top-level [AppScreen]. The connection
- * flows to Compose and derives the top-level [AppScreen]. The connection itself
+ * itself lives in the manager (shared with the foreground service), so it survives this ViewModel
- * lives in the manager (shared with the foreground service), so it survives this
+ * being cleared on Activity recreation.
- * ViewModel being cleared on Activity recreation.
  */
 class PlayerViewModel(application: Application) : AndroidViewModel(application) {
-
     private val manager = (application as EncoreApplication).manager
 
     val status = manager.status
@@ -39,7 +40,8 @@ class PlayerViewModel(application: Application) : AndroidViewModel(application)
     val serverHost = manager.serverHost
     val settings = manager.settings
 
-    val screen: StateFlow<AppScreen> = combine(
+    val screen: StateFlow<AppScreen> =
+        combine(
                 manager.connectionState,
                 manager.bootstrapping,
                 manager.settings,
@@ -48,40 +50,80 @@ class PlayerViewModel(application: Application) : AndroidViewModel(application)
                     booting -> AppScreen.Loading
                     connection is MpdConnectionState.Connected -> AppScreen.Player
                     connection is MpdConnectionState.Connecting -> AppScreen.Loading
-            connection is MpdConnectionState.Error -> AppScreen.Connect(saved, connection.message)
+                    connection is MpdConnectionState.Error ->
+                        AppScreen.Connect(saved, connection.message)
                     else -> AppScreen.Connect(saved, null) // Disconnected after startup
                 }
-    }.stateIn(
+            }
+            .stateIn(
                 scope = viewModelScope,
                 started = SharingStarted.WhileSubscribed(5_000),
                 initialValue = AppScreen.Loading,
             )
 
-    fun connect(host: String, port: Int) = manager.connect(host, port)
+    fun connect(
+        host: String,
+        port: Int,
+    ) = manager.connect(host, port)
+
     fun disconnect() = manager.disconnect()
+
     fun resetSettings() = manager.resetSettings()
+
     fun togglePlayPause() = manager.togglePlayPause()
+
     fun next() = manager.next()
+
     fun previous() = manager.previous()
+
     fun seekTo(seconds: Double) = manager.seekTo(seconds)
+
     fun setVolume(volume: Int) = manager.setVolume(volume)
+
     fun setRepeat(on: Boolean) = manager.setRepeat(on)
+
     fun setRandom(on: Boolean) = manager.setRandom(on)
+
     fun setConsume(on: Boolean) = manager.setConsume(on)
 
-    fun playAlbum(album: String, albumArtist: String?) = manager.playAlbum(album, albumArtist)
+    fun playAlbum(
-    fun queueAlbum(album: String, albumArtist: String?) = manager.queueAlbum(album, albumArtist)
+        album: String,
-    fun playAlbumNext(album: String, albumArtist: String?) = manager.playAlbumNext(album, albumArtist)
+        albumArtist: String?,
+    ) = manager.playAlbum(album, albumArtist)
+
+    fun queueAlbum(
+        album: String,
+        albumArtist: String?,
+    ) = manager.queueAlbum(album, albumArtist)
+
+    fun playAlbumNext(
+        album: String,
+        albumArtist: String?,
+    ) = manager.playAlbumNext(album, albumArtist)
+
     fun queueTrack(uri: String) = manager.queueTrack(uri)
+
     fun playTrackNext(uri: String) = manager.playTrackNext(uri)
-    suspend fun loadAlbumTracks(album: String, albumArtist: String?) =
+
-        manager.loadAlbumTracks(album, albumArtist)
+    suspend fun loadAlbumTracks(
+        album: String,
+        albumArtist: String?,
+    ) = manager.loadAlbumTracks(album, albumArtist)
+
     suspend fun loadAlbums() = manager.loadAlbums()
 
     fun playQueueItem(songId: Int) = manager.playQueueItem(songId)
+
     fun removeQueueItem(songId: Int) = manager.removeQueueItem(songId)
-    fun addTrackAt(uri: String, position: Int) = manager.addTrackAt(uri, position)
+
+    fun addTrackAt(
+        uri: String,
+        position: Int,
+    ) = manager.addTrackAt(uri, position)
+
     fun clearQueue() = manager.clearQueue()
+
     suspend fun loadStatistics() = manager.loadStatistics()
+
     suspend fun loadQueue() = manager.loadQueue()
 }

app/src/main/kotlin/ca/ksamad/encore/ui/QueueScreen.kt

@@ -54,22 +54,25 @@ import ca.ksamad.encore.playback.SongArt
 import kotlinx.coroutines.launch
 
 /**
- * "Up next": the tracks that will auto-play from the current one to the end of
+ * "Up next": the tracks that will auto-play from the current one to the end of the queue. We
- * the queue. We deliberately drop the already-played prefix (MPD keeps played
+ * deliberately drop the already-played prefix (MPD keeps played tracks in the queue unless consume
- * tracks in the queue unless consume mode is on) so the list reflects what will
+ * mode is on) so the list reflects what will actually play before MPD stops — and it shrinks as
- * actually play before MPD stops — and it shrinks as playback advances even
+ * playback advances even without consume. Repeat/single change that, so we caption those cases.
- * without consume. Repeat/single change that, so we caption those cases.
  *
- * The full queue is re-fetched when its version changes; the upcoming slice is
+ * The full queue is re-fetched when its version changes; the upcoming slice is derived from the
- * derived from the live current-song position, so it updates as playback moves.
+ * live current-song position, so it updates as playback moves.
  */
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
-fun QueueScreen(vm: PlayerViewModel, onBack: () -> Unit) {
+fun QueueScreen(
+    vm: PlayerViewModel,
+    onBack: () -> Unit,
+) {
     val status by vm.status.collectAsStateWithLifecycle()
 
     // Reload the full queue when the queue version bumps (edits/consume).
-    val fullQueue by produceState<List<MpdSong>?>(initialValue = null, status?.playlistVersion) {
+    val fullQueue by
+        produceState<List<MpdSong>?>(initialValue = null, status?.playlistVersion) {
             value = vm.loadQueue()
         }
 
@@ -81,7 +84,8 @@ fun QueueScreen(vm: PlayerViewModel, onBack: () -> Unit) {
     // Slice from the current song to the end. `song` is the current queue index.
     val currentPos = status?.song
     val upcoming: List<MpdSong>? = fullQueue?.let { q ->
-        val slice = if (currentPos != null && currentPos in q.indices) q.subList(currentPos, q.size) else q
+        val slice =
+            if (currentPos != null && currentPos in q.indices) q.subList(currentPos, q.size) else q
         if (pendingRemoval.isEmpty()) slice else slice.filter { it.id !in pendingRemoval }
     }
     val hasCurrent = currentPos != null && (fullQueue?.indices?.contains(currentPos) == true)
@@ -93,13 +97,15 @@ fun QueueScreen(vm: PlayerViewModel, onBack: () -> Unit) {
     // Undo affordance for swipe-to-remove.
     val snackbarHostState = remember { SnackbarHostState() }
     val scope = rememberCoroutineScope()
+
     fun removeSong(song: MpdSong) {
         val id = song.id ?: return
         pendingRemoval = pendingRemoval + id
         vm.removeQueueItem(id)
         snackbarHostState.currentSnackbarData?.dismiss()
         scope.launch {
-            val result = snackbarHostState.showSnackbar(
+            val result =
+                snackbarHostState.showSnackbar(
                     message = "Removed “${song.title ?: song.uri}”",
                     actionLabel = "Undo",
                     duration = SnackbarDuration.Long,
@@ -133,25 +139,34 @@ fun QueueScreen(vm: PlayerViewModel, onBack: () -> Unit) {
         snackbarHost = { SnackbarHost(snackbarHostState) },
     ) { innerPadding ->
         when {
-            upcoming == null -> Box(
+            upcoming == null -> {
+                Box(
                     Modifier.fillMaxSize().padding(innerPadding),
                     contentAlignment = Alignment.Center,
-            ) { CircularProgressIndicator() }
+                ) {
+                    CircularProgressIndicator()
+                }
+            }
 
-            upcoming.isEmpty() -> Box(
+            upcoming.isEmpty() -> {
+                Box(
                     Modifier.fillMaxSize().padding(innerPadding),
                     contentAlignment = Alignment.Center,
-            ) { Text("Nothing queued", color = MaterialTheme.colorScheme.onSurfaceVariant) }
+                ) {
+                    Text("Nothing queued", color = MaterialTheme.colorScheme.onSurfaceVariant)
+                }
+            }
 
-            else -> LazyColumn(modifier = Modifier.padding(innerPadding)) {
+            else -> {
+                LazyColumn(modifier = Modifier.padding(innerPadding)) {
                     playbackModeCaption(status)?.let { caption ->
                         item {
                             Text(
                                 caption,
                                 style = MaterialTheme.typography.bodySmall,
                                 color = MaterialTheme.colorScheme.onSurfaceVariant,
-                            modifier = Modifier
+                                modifier =
-                                .fillMaxWidth()
+                                    Modifier.fillMaxWidth()
                                         .padding(horizontal = 16.dp, vertical = 8.dp),
                             )
                         }
@@ -163,10 +178,19 @@ fun QueueScreen(vm: PlayerViewModel, onBack: () -> Unit) {
                         // The current track and id-less entries aren't swipe-removable —
                         // removing the current one would disrupt playback.
                         if (isCurrent || id == null) {
-                        QueueRow(song, isCurrent, onClick = { id?.let { vm.playQueueItem(it) } })
+                            QueueRow(
+                                song,
+                                isCurrent,
+                                onClick = { id?.let { vm.playQueueItem(it) } },
+                            )
                         } else {
                             SwipeToRemoveRow(onRemove = { removeSong(song) }) {
-                            QueueRow(song, isCurrent = false, onClick = { vm.playQueueItem(id) })
+                                QueueRow(
+                                    song,
+                                    isCurrent = false,
+                                    onClick = { vm.playQueueItem(id) },
+                                )
+                            }
                         }
                     }
                 }
@@ -180,10 +204,14 @@ fun QueueScreen(vm: PlayerViewModel, onBack: () -> Unit) {
             title = { Text("Clear the queue?") },
             text = { Text("This removes every track from the queue and stops playback.") },
             confirmButton = {
-                TextButton(onClick = {
+                TextButton(
+                    onClick = {
                         vm.clearQueue()
                         confirmClear = false
-                }) { Text("Clear") }
+                    }
+                ) {
+                    Text("Clear")
+                }
             },
             dismissButton = {
                 TextButton(onClick = { confirmClear = false }) { Text("Cancel") }
@@ -194,10 +222,15 @@ fun QueueScreen(vm: PlayerViewModel, onBack: () -> Unit) {
 
 /** A single queue entry — art, title/artist, and a duration or now-playing badge. */
 @Composable
-private fun QueueRow(song: MpdSong, isCurrent: Boolean, onClick: () -> Unit) {
+private fun QueueRow(
+    song: MpdSong,
+    isCurrent: Boolean,
+    onClick: () -> Unit,
+) {
     ListItem(
         modifier = Modifier.clickable(onClick = onClick),
-        colors = if (isCurrent) {
+        colors =
+            if (isCurrent) {
                 ListItemDefaults.colors(containerColor = MaterialTheme.colorScheme.primaryContainer)
             } else {
                 ListItemDefaults.colors()
@@ -217,10 +250,12 @@ private fun QueueRow(song: MpdSong, isCurrent: Boolean, onClick: () -> Unit) {
                 fontWeight = if (isCurrent) FontWeight.Bold else FontWeight.Normal,
             )
         },
-        supportingContent = song.artist?.let {
+        supportingContent =
+            song.artist?.let {
                 { Text(it, maxLines = 1, overflow = TextOverflow.Ellipsis) }
             },
-        trailingContent = if (isCurrent) {
+        trailingContent =
+            if (isCurrent) {
                 { Icon(Icons.Filled.VolumeUp, contentDescription = "Now playing") }
             } else {
                 song.duration?.let { { Text(formatDuration(it)) } }
@@ -229,14 +264,18 @@ private fun QueueRow(song: MpdSong, isCurrent: Boolean, onClick: () -> Unit) {
 }
 
 /**
- * Wraps [content] in a swipe-to-remove gesture: a swipe in either direction
+ * Wraps [content] in a swipe-to-remove gesture: a swipe in either direction settles the row
- * settles the row off-screen and calls [onRemove]. The reveal is a red trash
+ * off-screen and calls [onRemove]. The reveal is a red trash background on whichever edge is being
- * background on whichever edge is being swiped from.
+ * swiped from.
  */
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
-private fun SwipeToRemoveRow(onRemove: () -> Unit, content: @Composable () -> Unit) {
+private fun SwipeToRemoveRow(
-    val state = rememberSwipeToDismissBoxState(
+    onRemove: () -> Unit,
+    content: @Composable () -> Unit,
+) {
+    val state =
+        rememberSwipeToDismissBoxState(
             confirmValueChange = { target ->
                 if (target != SwipeToDismissBoxValue.Settled) {
                     onRemove()
@@ -244,7 +283,7 @@ private fun SwipeToRemoveRow(onRemove: () -> Unit, content: @Composable () -> Un
                 } else {
                     false
                 }
-        },
+            }
         )
     SwipeToDismissBox(
         state = state,
@@ -262,14 +301,14 @@ private fun RemoveBackground(direction: SwipeToDismissBoxValue) {
         Box(Modifier.fillMaxSize())
         return
     }
-    val alignment = if (direction == SwipeToDismissBoxValue.StartToEnd) {
+    val alignment =
+        if (direction == SwipeToDismissBoxValue.StartToEnd) {
             Alignment.CenterStart
         } else {
             Alignment.CenterEnd
         }
     Box(
-        Modifier
+        Modifier.fillMaxSize()
-            .fillMaxSize()
             .background(MaterialTheme.colorScheme.errorContainer)
             .padding(horizontal = 24.dp),
         contentAlignment = alignment,
@@ -283,13 +322,14 @@ private fun RemoveBackground(direction: SwipeToDismissBoxValue) {
 }
 
 /** Explains what will actually happen at the end of the list, given the modes. */
-private fun playbackModeCaption(status: MpdStatus?): String? = when {
+private fun playbackModeCaption(status: MpdStatus?): String? =
+    when {
         status == null -> null
         status.repeat && status.single -> "Repeating the current track."
         status.single -> "Single mode — stops after the current track."
         status.repeat -> "Repeat on — the queue loops, so playback won't stop."
         else -> null
-}
+    }
 
 /** `m:ss` for a duration in seconds. Shared across the queue/album track lists. */
 internal fun formatDuration(seconds: Double): String {

app/src/main/kotlin/ca/ksamad/encore/ui/SettingsScreen.kt

@@ -42,12 +42,15 @@ import java.util.Date
 import java.util.Locale
 
 /**
- * Settings: shows the current server and offers to switch servers or reset all
+ * Settings: shows the current server and offers to switch servers or reset all saved settings.
- * saved settings. Reached from the player via the gear icon; [onBack] pops back.
+ * Reached from the player via the gear icon; [onBack] pops back.
  */
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
-fun SettingsScreen(vm: PlayerViewModel, onBack: () -> Unit) {
+fun SettingsScreen(
+    vm: PlayerViewModel,
+    onBack: () -> Unit,
+) {
     val settings by vm.settings.collectAsStateWithLifecycle()
     val status by vm.status.collectAsStateWithLifecycle()
     var confirmReset by remember { mutableStateOf(false) }
@@ -55,7 +58,8 @@ fun SettingsScreen(vm: PlayerViewModel, onBack: () -> Unit) {
     // Server statistics (`stats`), fetched once when the screen opens. `null`
     // means either still loading or unavailable — [statsLoaded] disambiguates.
     var statsLoaded by remember { mutableStateOf(false) }
-    val stats by produceState<MpdStatistics?>(initialValue = null) {
+    val stats by
+        produceState<MpdStatistics?>(initialValue = null) {
             value = vm.loadStatistics()
             statsLoaded = true
         }
@@ -70,14 +74,14 @@ fun SettingsScreen(vm: PlayerViewModel, onBack: () -> Unit) {
                     }
                 },
             )
-        },
+        }
     ) { innerPadding ->
         Column(
-            modifier = Modifier
+            modifier =
-                .fillMaxSize()
+                Modifier.fillMaxSize()
                     .padding(innerPadding)
                     .verticalScroll(rememberScrollState())
-                .padding(horizontal = 8.dp),
+                    .padding(horizontal = 8.dp)
         ) {
             Text(
                 "Server",
@@ -122,19 +126,24 @@ fun SettingsScreen(vm: PlayerViewModel, onBack: () -> Unit) {
                 modifier = Modifier.padding(start = 8.dp, top = 20.dp, bottom = 4.dp),
             )
             when {
-                !statsLoaded -> ListItem(
+                !statsLoaded -> {
+                    ListItem(
                         headlineContent = { Text("Loading…") },
                         trailingContent = {
                             CircularProgressIndicator(modifier = Modifier.size(20.dp))
                         },
                     )
+                }
 
-                stats == null -> ListItem(
+                stats == null -> {
+                    ListItem(
                         headlineContent = { Text("Statistics unavailable") },
                         supportingContent = { Text("The server didn't report any statistics") },
                     )
+                }
 
-                else -> stats?.let { s ->
+                else -> {
+                    stats?.let { s ->
                         StatRow("Artists", formatCount(s.artists))
                         StatRow("Albums", formatCount(s.albums))
                         StatRow("Tracks", formatCount(s.songs))
@@ -144,27 +153,28 @@ fun SettingsScreen(vm: PlayerViewModel, onBack: () -> Unit) {
                         StatRow("Last updated", formatTimestamp(s.dbUpdateEpochSeconds))
                     }
                 }
+            }
 
             Spacer(Modifier.height(24.dp))
 
             OutlinedButton(
-                onClick = { onBack(); vm.disconnect() },
+                onClick = {
-                modifier = Modifier
+                    onBack()
-                    .fillMaxWidth()
+                    vm.disconnect()
-                    .padding(horizontal = 8.dp),
+                },
+                modifier = Modifier.fillMaxWidth().padding(horizontal = 8.dp),
             ) {
                 Text("Change server")
             }
             Spacer(Modifier.height(8.dp))
             Button(
                 onClick = { confirmReset = true },
-                colors = ButtonDefaults.buttonColors(
+                colors =
+                    ButtonDefaults.buttonColors(
                         containerColor = MaterialTheme.colorScheme.errorContainer,
                         contentColor = MaterialTheme.colorScheme.onErrorContainer,
                     ),
-                modifier = Modifier
+                modifier = Modifier.fillMaxWidth().padding(horizontal = 8.dp),
-                    .fillMaxWidth()
-                    .padding(horizontal = 8.dp),
             ) {
                 Text("Reset settings")
             }
@@ -177,11 +187,15 @@ fun SettingsScreen(vm: PlayerViewModel, onBack: () -> Unit) {
             title = { Text("Reset settings?") },
             text = { Text("This forgets the saved server and disconnects.") },
             confirmButton = {
-                TextButton(onClick = {
+                TextButton(
+                    onClick = {
                         confirmReset = false
                         onBack()
                         vm.resetSettings()
-                }) { Text("Reset") }
+                    }
+                ) {
+                    Text("Reset")
+                }
             },
             dismissButton = {
                 TextButton(onClick = { confirmReset = false }) { Text("Cancel") }
@@ -192,7 +206,10 @@ fun SettingsScreen(vm: PlayerViewModel, onBack: () -> Unit) {
 
 /** A label/value line matching the Host/Port rows above. */
 @Composable
-private fun StatRow(label: String, value: String) {
+private fun StatRow(
+    label: String,
+    value: String,
+) {
     ListItem(
         headlineContent = { Text(label) },
         trailingContent = { Text(value) },
@@ -203,8 +220,8 @@ private fun StatRow(label: String, value: String) {
 private fun formatCount(n: Int): String = "%,d".format(n)
 
 /**
- * A duration in seconds as a compact `Xd Yh Zm`, dropping leading zero units but
+ * A duration in seconds as a compact `Xd Yh Zm`, dropping leading zero units but always showing at
- * always showing at least minutes. Non-positive values render as an em dash.
+ * least minutes. Non-positive values render as an em dash.
  */
 private fun formatStatDuration(totalSeconds: Long): String {
     if (totalSeconds <= 0) return "—"

app/src/main/kotlin/ca/ksamad/encore/ui/SwipeActions.kt

@@ -23,14 +23,12 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.unit.dp
 
 /**
- * Wraps [content] in the app's shared "queue swipe" affordance: swipe right to
+ * Wraps [content] in the app's shared "queue swipe" affordance: swipe right to [onAddToQueue]
- * [onAddToQueue] (append), swipe left to [onPlayNext] (insert after the current
+ * (append), swipe left to [onPlayNext] (insert after the current track). Used for both album rows
- * track). Used for both album rows and individual tracks so the gesture and its
+ * and individual tracks so the gesture and its meaning stay identical wherever it appears.
- * meaning stay identical wherever it appears.
  *
- * Both are one-shot actions, not deletions, so the row always springs back and
+ * Both are one-shot actions, not deletions, so the row always springs back and stays in the list —
- * stays in the list — [content] should be opaque (e.g. a `ListItem`) so it hides
+ * [content] should be opaque (e.g. a `ListItem`) so it hides the coloured reveal once settled.
- * the coloured reveal once settled.
  */
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
@@ -39,15 +37,22 @@ fun QueueSwipeRow(
     onPlayNext: () -> Unit,
     content: @Composable () -> Unit,
 ) {
-    val state = rememberSwipeToDismissBoxState(
+    val state =
+        rememberSwipeToDismissBoxState(
             confirmValueChange = { target ->
                 when (target) {
-                SwipeToDismissBoxValue.StartToEnd -> onAddToQueue()
+                    SwipeToDismissBoxValue.StartToEnd -> {
-                SwipeToDismissBoxValue.EndToStart -> onPlayNext()
+                        onAddToQueue()
+                    }
+
+                    SwipeToDismissBoxValue.EndToStart -> {
+                        onPlayNext()
+                    }
+
                     SwipeToDismissBoxValue.Settled -> {}
                 }
                 false // Never settle to dismissed — snap back and keep the row.
-        },
+            }
         )
 
     SwipeToDismissBox(
@@ -59,9 +64,9 @@ fun QueueSwipeRow(
 }
 
 /**
- * The coloured reveal shown behind a swiping row: an "Add to queue" hint on the
+ * The coloured reveal shown behind a swiping row: an "Add to queue" hint on the leading edge (swipe
- * leading edge (swipe right) and a "Play next" hint on the trailing edge (swipe
+ * right) and a "Play next" hint on the trailing edge (swipe left). Renders empty while the row is
- * left). Renders empty while the row is settled.
+ * settled.
  */
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
@@ -72,12 +77,14 @@ private fun SwipeActionBackground(direction: SwipeToDismissBoxValue) {
     }
 
     val queueing = direction == SwipeToDismissBoxValue.StartToEnd
-    val container = if (queueing) {
+    val container =
+        if (queueing) {
             MaterialTheme.colorScheme.secondaryContainer
         } else {
             MaterialTheme.colorScheme.tertiaryContainer
         }
-    val onContainer = if (queueing) {
+    val onContainer =
+        if (queueing) {
             MaterialTheme.colorScheme.onSecondaryContainer
         } else {
             MaterialTheme.colorScheme.onTertiaryContainer
@@ -86,10 +93,7 @@ private fun SwipeActionBackground(direction: SwipeToDismissBoxValue) {
     val label = if (queueing) "Add to queue" else "Play next"
 
     Box(
-        Modifier
+        Modifier.fillMaxSize().background(container).padding(horizontal = 24.dp),
-            .fillMaxSize()
-            .background(container)
-            .padding(horizontal = 24.dp),
         contentAlignment = if (queueing) Alignment.CenterStart else Alignment.CenterEnd,
     ) {
         Row(verticalAlignment = Alignment.CenterVertically) {

app/src/test/kotlin/ca/ksamad/encore/ExampleUnitTest.kt

@@ -4,9 +4,8 @@ import org.junit.Assert.assertEquals
 import org.junit.Test
 
 /**
- * A plain JVM unit test (runs on your machine, no device/emulator needed).
+ * A plain JVM unit test (runs on your machine, no device/emulator needed). `gradle
- * `gradle testDebugUnitTest` runs these — that's what the Nix build's check
+ * testDebugUnitTest` runs these — that's what the Nix build's check phase invokes.
- * phase invokes.
  */
 class ExampleUnitTest {
     @Test

app/src/test/kotlin/ca/ksamad/encore/mpd/MpdClientIntegrationTest.kt

@@ -8,16 +8,15 @@ import org.junit.Assume.assumeTrue
 import org.junit.Test
 
 /**
- * Live end-to-end test of [MpdClient] against a real server (skipped unless
+ * Live end-to-end test of [MpdClient] against a real server (skipped unless `MPD_HOST` is set — see
- * `MPD_HOST` is set — see [MpdServerIntegrationTest]).
+ * [MpdServerIntegrationTest]).
  *
- * The interesting part is the idle round-trip: we change the volume on the
+ * The interesting part is the idle round-trip: we change the volume on the **command** connection
- * **command** connection and then wait for that change to arrive back through
+ * and then wait for that change to arrive back through the **idle** connection into the `status`
- * the **idle** connection into the `status` flow — proving the two-connection
+ * flow — proving the two-connection push architecture actually works. The volume nudge is reverted
- * push architecture actually works. The volume nudge is reverted afterwards.
+ * afterwards.
  */
 class MpdClientIntegrationTest {
-
     private val host = System.getenv("MPD_HOST")
     private val port = System.getenv("MPD_PORT")?.toIntOrNull() ?: MpdConnection.DEFAULT_PORT
     private val password = System.getenv("MPD_PASSWORD")
@@ -35,7 +34,9 @@ class MpdClientIntegrationTest {
 
             // Initial state, primed during connect().
             val initial = withTimeout(5_000) { client.status.first { it != null } }!!
-            println("connected. state=${initial.state} volume=${initial.volume} song='${client.currentSong.value?.title}'")
+            println(
+                "connected. state=${initial.state} volume=${initial.volume} song='${client.currentSong.value?.title}'"
+            )
 
             val startVolume = initial.volume
             if (startVolume == null) {
@@ -49,7 +50,8 @@ class MpdClientIntegrationTest {
             client.setVolume(nudged)
 
             // ...and wait for the change to come back via the idle connection.
-            val observed = withTimeout(5_000) {
+            val observed =
+                withTimeout(5_000) {
                     client.status.first { it?.volume == nudged }
                 }!!
             println("idle push observed: status flow now reports volume=${observed.volume} ✔")

app/src/test/kotlin/ca/ksamad/encore/mpd/MpdConnectionTest.kt

@@ -1,26 +1,28 @@
 package ca.ksamad.encore.mpd
 
+import java.io.ByteArrayInputStream
+import java.io.ByteArrayOutputStream
 import org.junit.Assert.assertArrayEquals
 import org.junit.Assert.assertEquals
 import org.junit.Assert.assertNull
 import org.junit.Assert.assertThrows
 import org.junit.Assert.assertTrue
 import org.junit.Test
-import java.io.ByteArrayInputStream
-import java.io.ByteArrayOutputStream
 
 /**
- * Drives [MpdConnection] against in-memory streams, so the whole text protocol
+ * Drives [MpdConnection] against in-memory streams, so the whole text protocol (greeting, key/value
- * (greeting, key/value parsing, ACK handling, binary payloads) is exercised
+ * parsing, ACK handling, binary payloads) is exercised with no socket.
- * with no socket.
  */
 class MpdConnectionTest {
+    private fun conn(
+        serverBytes: ByteArray,
+        out: ByteArrayOutputStream = ByteArrayOutputStream(),
+    ) = MpdConnection(ByteArrayInputStream(serverBytes), out)
 
-    private fun conn(serverBytes: ByteArray, out: ByteArrayOutputStream = ByteArrayOutputStream()) =
+    private fun conn(
-        MpdConnection(ByteArrayInputStream(serverBytes), out)
+        serverText: String,
-
+        out: ByteArrayOutputStream = ByteArrayOutputStream(),
-    private fun conn(serverText: String, out: ByteArrayOutputStream = ByteArrayOutputStream()) =
+    ) = conn(serverText.toByteArray(Charsets.UTF_8), out)
-        conn(serverText.toByteArray(Charsets.UTF_8), out)
 
     @Test
     fun handshake_parsesVersion() {
@@ -83,7 +85,8 @@ class MpdConnectionTest {
     @Test
     fun executeList_splitsResponsesOnListOk() {
         // command_list_ok_begin: each sub-response ends with list_OK, then final OK.
-        val server = "OK MPD 0.23.5\n" +
+        val server =
+            "OK MPD 0.23.5\n" +
                 "volume: 50\nstate: play\nlist_OK\n" +
                 "file: a.mp3\nTitle: A\nlist_OK\n" +
                 "OK\n"
@@ -98,7 +101,10 @@ class MpdConnectionTest {
         assertEquals("a.mp3", responses[1]["file"])
         assertEquals("A", responses[1]["Title"])
 
-        assertTrue(out.toString("UTF-8").startsWith("command_list_ok_begin\nstatus\ncurrentsong\ncommand_list_end\n"))
+        assertTrue(
+            out.toString("UTF-8")
+                .startsWith("command_list_ok_begin\nstatus\ncurrentsong\ncommand_list_end\n")
+        )
     }
 
     @Test

app/src/test/kotlin/ca/ksamad/encore/mpd/MpdProtocolTest.kt

@@ -4,7 +4,6 @@ import org.junit.Assert.assertEquals
 import org.junit.Test
 
 class MpdProtocolTest {
-
     @Test
     fun quote_wrapsPlainArg() {
         assertEquals("\"hello\"", MpdProtocol.quote("hello"))

app/src/test/kotlin/ca/ksamad/encore/mpd/MpdServerIntegrationTest.kt

@@ -8,19 +8,17 @@ import org.junit.Assume.assumeTrue
 import org.junit.Test
 
 /**
- * A *live* smoke test against a real MPD server. It is skipped unless `MPD_HOST`
+ * A *live* smoke test against a real MPD server. It is skipped unless `MPD_HOST` is set, so the
- * is set, so the ordinary (and Nix) build never touches the network:
+ * ordinary (and Nix) build never touches the network:
- *
  * ```
  * MPD_HOST=192.168.1.50 MPD_PORT=6600 [MPD_PASSWORD=secret] \
  *   ./gradlew testDebugUnitTest --tests '*MpdServerIntegrationTest' --rerun-tasks
  * ```
  *
- * It connects, runs `status` / `currentsong` / `stats`, and prints the parsed
+ * It connects, runs `status` / `currentsong` / `stats`, and prints the parsed models so you can
- * models so you can eyeball that the protocol layer really talks to your server.
+ * eyeball that the protocol layer really talks to your server.
  */
 class MpdServerIntegrationTest {
-
     private val host = System.getenv("MPD_HOST")
     private val port = System.getenv("MPD_PORT")?.toIntOrNull() ?: MpdConnection.DEFAULT_PORT
     private val password = System.getenv("MPD_PASSWORD")
@@ -44,10 +42,14 @@ class MpdServerIntegrationTest {
             println("status  : $status")
 
             val song = MpdSong.from(conn.execute(MpdCommands.currentSong()).toMap())
-            println("current : ${song?.let { "${it.artist} — ${it.title} (${it.uri})" } ?: "<nothing playing>"}")
+            println(
+                "current : ${song?.let { "${it.artist} — ${it.title} (${it.uri})" } ?: "<nothing playing>"}"
+            )
 
             val stats = MpdStatistics.from(conn.execute(MpdCommands.stats()).toMap())
-            println("stats   : ${stats.songs} songs, ${stats.albums} albums, ${stats.artists} artists")
+            println(
+                "stats   : ${stats.songs} songs, ${stats.albums} albums, ${stats.artists} artists"
+            )
 
             // Prove the raw commands list works too — a good connectivity sanity check.
             val commands = conn.execute(MpdProtocol.command("commands")).getAll("command")

app/src/test/kotlin/ca/ksamad/encore/mpd/model/MpdModelTest.kt

@@ -8,10 +8,10 @@ import org.junit.Assert.assertTrue
 import org.junit.Test
 
 class MpdModelTest {
-
     @Test
     fun status_parsesTypicalPlayingSnapshot() {
-        val s = MpdStatus.from(
+        val s =
+            MpdStatus.from(
                 mapOf(
                     "volume" to "80",
                     "repeat" to "0",
@@ -49,7 +49,8 @@ class MpdModelTest {
 
     @Test
     fun song_parsesTagsAndDuration() {
-        val song = MpdSong.from(
+        val song =
+            MpdSong.from(
                 mapOf(
                     "file" to "music/nin/closer.flac",
                     "Title" to "Closer",
@@ -82,10 +83,17 @@ class MpdModelTest {
     @Test
     fun response_splitSeparatesRepeatedSongBlocks() {
         // Two songs from a playlistinfo-style response, split on "file".
-        val resp = MpdResponse(
+        val resp =
+            MpdResponse(
                 listOf(
-                "file" to "a.mp3", "Title" to "A", "Pos" to "0", "Id" to "1",
+                    "file" to "a.mp3",
-                "file" to "b.mp3", "Title" to "B", "Pos" to "1", "Id" to "2",
+                    "Title" to "A",
+                    "Pos" to "0",
+                    "Id" to "1",
+                    "file" to "b.mp3",
+                    "Title" to "B",
+                    "Pos" to "1",
+                    "Id" to "2",
                 )
             )
         val songs = resp.split().mapNotNull { MpdSong.from(it) }
@@ -98,7 +106,8 @@ class MpdModelTest {
     @Test
     fun albums_parseGroupedByArtist() {
         // `list album group albumartist` style output.
-        val resp = MpdResponse(
+        val resp =
+            MpdResponse(
                 listOf(
                     "AlbumArtist" to "Pink Floyd",
                     "Album" to "Animals",
@@ -122,7 +131,8 @@ class MpdModelTest {
 
     @Test
     fun statistics_parseCounts() {
-        val stats = MpdStatistics.from(
+        val stats =
+            MpdStatistics.from(
                 mapOf(
                     "artists" to "312",
                     "albums" to "540",