choose the stream bitrate and format from settings

app/src/main/kotlin/com/subtracks/data/prefs/UserPreferences.kt

@@ -4,6 +4,7 @@ import android.content.Context
 import androidx.datastore.core.DataStore
 import androidx.datastore.preferences.core.Preferences
 import androidx.datastore.preferences.core.edit
+import androidx.datastore.preferences.core.intPreferencesKey
 import androidx.datastore.preferences.core.stringPreferencesKey
 import androidx.datastore.preferences.preferencesDataStore
 import kotlinx.coroutines.flow.Flow
@@ -25,8 +26,24 @@ class UserPreferences(
         store.edit { prefs -> prefs[ALBUM_SORT] = sort.name }
     }
 
+    val maxBitrate: Flow<Int> = store.data.map { prefs -> prefs[MAX_BITRATE] ?: 0 }
+
+    suspend fun setMaxBitrate(kbps: Int) {
+        store.edit { prefs -> prefs[MAX_BITRATE] = kbps }
+    }
+
+    val streamFormat: Flow<String?> = store.data.map { prefs -> prefs[STREAM_FORMAT] }
+
+    suspend fun setStreamFormat(format: String?) {
+        store.edit { prefs ->
+            if (format.isNullOrEmpty()) prefs.remove(STREAM_FORMAT) else prefs[STREAM_FORMAT] = format
+        }
+    }
+
     private companion object {
         val ALBUM_SORT = stringPreferencesKey("album_sort")
+        val MAX_BITRATE = intPreferencesKey("max_bitrate")
+        val STREAM_FORMAT = stringPreferencesKey("stream_format")
     }
 }
 

app/src/main/kotlin/com/subtracks/data/repo/SourceRepository.kt

@@ -5,6 +5,7 @@ import com.subtracks.data.model.CoverArtRef
 import com.subtracks.data.model.Source
 import com.subtracks.data.model.SubsonicConfig
 import com.subtracks.data.model.SubsonicSource
+import com.subtracks.data.prefs.UserPreferences
 import com.subtracks.data.source.subsonic.SubsonicClient
 import com.subtracks.data.sync.SyncService
 import kotlinx.coroutines.CoroutineScope
@@ -12,6 +13,8 @@ import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.SupervisorJob
 import kotlinx.coroutines.cancel
 import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.combine
+import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import okhttp3.HttpUrl.Companion.toHttpUrl
@@ -21,6 +24,7 @@ import com.subtracks.data.source.subsonic.SubsonicSource as SubsonicMusicSource
 class SourceRepository(
     private val db: SubtracksDatabase,
     private val http: OkHttpClient,
+    private val prefs: UserPreferences,
 ) {
     private val scope = CoroutineScope(SupervisorJob() + Dispatchers.Default)
 
@@ -29,9 +33,12 @@ class SourceRepository(
 
     init {
         scope.launch {
-            db.sourcesDao().activeSubsonicConfig().collect { config ->
+            combine(
-                active = config?.toMusicSource()
+                db.sourcesDao().activeSubsonicConfig(),
-            }
+                prefs.maxBitrate,
+                prefs.streamFormat,
+            ) { config, maxBitrate, streamFormat -> config?.toMusicSource(maxBitrate, streamFormat) }
+                .collect { active = it }
         }
     }
 
@@ -111,11 +118,19 @@ class SourceRepository(
     suspend fun sync(): Result<Unit> =
         runCatching {
             val config = db.sourcesDao().activeSubsonicConfigOnce() ?: error("No server configured")
-            SyncService(db, config.toMusicSource()).sync()
+            SyncService(db, config.toMusicSource(prefs.maxBitrate.first(), prefs.streamFormat.first())).sync()
         }
 
-    private fun SubsonicConfig.toMusicSource(): SubsonicMusicSource =
+    private fun SubsonicConfig.toMusicSource(
-        SubsonicMusicSource(id, client(address, username, password, useTokenAuth))
+        maxBitrate: Int,
+        streamFormat: String?,
+    ): SubsonicMusicSource =
+        SubsonicMusicSource(
+            id = id,
+            client = client(address, username, password, useTokenAuth),
+            maxBitrate = maxBitrate,
+            streamFormat = streamFormat,
+        )
 
     private fun client(
         address: String,

app/src/main/kotlin/com/subtracks/di/AppModule.kt

@@ -27,7 +27,7 @@ fun appModule(
     single { createAndroidDatabase(context) }
     single { http }
     single { createUserPreferences(context) }
-    single { SourceRepository(get(), get()) }
+    single { SourceRepository(get(), get(), get()) }
     single { LibraryRepository(get(), get()) }
     single { SyncManager(get()) }
     single { QueueRepository(get()) }
@@ -35,7 +35,7 @@ fun appModule(
     single { PlaybackController(get(), get(), get()) }
     viewModel { RootViewModel(get()) }
     viewModel { LibraryViewModel(get(), get(), get(), get()) }
-    viewModel { SettingsViewModel(get()) }
+    viewModel { SettingsViewModel(get(), get()) }
     viewModel { AddSourceViewModel(get(), get()) }
     viewModel { params -> AlbumDetailViewModel(get(), get(), get(), params.get()) }
     viewModel { params -> PlaylistDetailViewModel(get(), get(), get(), params.get()) }

app/src/main/kotlin/com/subtracks/ui/settings/SettingsScreen.kt

@@ -1,6 +1,8 @@
 package com.subtracks.ui.settings
 
+import androidx.compose.foundation.clickable
 import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.fillMaxSize
@@ -13,6 +15,7 @@ import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.automirrored.rounded.ArrowBack
 import androidx.compose.material.icons.rounded.Add
 import androidx.compose.material.icons.rounded.Delete
+import androidx.compose.material3.AlertDialog
 import androidx.compose.material3.Button
 import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.Icon
@@ -23,9 +26,14 @@ import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.RadioButton
 import androidx.compose.material3.Scaffold
 import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
 import androidx.compose.material3.TopAppBar
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.text.style.TextOverflow
@@ -34,6 +42,11 @@ import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import com.subtracks.data.model.Source
 import org.koin.compose.viewmodel.koinViewModel
 
+private val bitrateOptions = listOf(0, 24, 32, 64, 96, 128, 192, 256, 320)
+private val streamFormats = listOf(null, "mp3", "opus", "ogg", "webm", "aac", "flac")
+
+private enum class SettingsDialog { Bitrate, Format }
+
 @Composable
 fun SettingsRoute(
     onAddServer: () -> Unit,
@@ -42,11 +55,17 @@ fun SettingsRoute(
 ) {
     val sources by viewModel.sources.collectAsStateWithLifecycle()
     val activeSourceId by viewModel.activeSourceId.collectAsStateWithLifecycle()
+    val maxBitrate by viewModel.maxBitrate.collectAsStateWithLifecycle()
+    val streamFormat by viewModel.streamFormat.collectAsStateWithLifecycle()
     SettingsScreen(
         sources = sources,
         activeSourceId = activeSourceId,
+        maxBitrate = maxBitrate,
+        streamFormat = streamFormat,
         onSelectSource = viewModel::selectSource,
         onDeleteSource = viewModel::deleteSource,
+        onMaxBitrateChange = viewModel::setMaxBitrate,
+        onStreamFormatChange = viewModel::setStreamFormat,
         onAddServer = onAddServer,
         onBack = onBack,
     )
@@ -57,12 +76,18 @@ fun SettingsRoute(
 fun SettingsScreen(
     sources: List<Source>,
     activeSourceId: Long?,
+    maxBitrate: Int,
+    streamFormat: String?,
     onSelectSource: (Long) -> Unit,
     onDeleteSource: (Long) -> Unit,
+    onMaxBitrateChange: (Int) -> Unit,
+    onStreamFormatChange: (String?) -> Unit,
     onAddServer: () -> Unit,
     onBack: () -> Unit,
     modifier: Modifier = Modifier,
 ) {
+    var dialog by remember { mutableStateOf<SettingsDialog?>(null) }
+
     Scaffold(
         modifier = modifier,
         topBar = {
@@ -111,8 +136,90 @@ fun SettingsScreen(
                     }
                 }
             }
+            item { SectionHeader("Network") }
+            item {
+                ListItem(
+                    headlineContent = { Text("Maximum bitrate") },
+                    supportingContent = { Text(bitrateLabel(maxBitrate)) },
+                    modifier = Modifier.clickable { dialog = SettingsDialog.Bitrate },
+                    colors = ListItemDefaults.colors(containerColor = Color.Transparent),
+                )
+            }
+            item {
+                ListItem(
+                    headlineContent = { Text("Preferred stream format") },
+                    supportingContent = { Text(streamFormat ?: "Use server default") },
+                    modifier = Modifier.clickable { dialog = SettingsDialog.Format },
+                    colors = ListItemDefaults.colors(containerColor = Color.Transparent),
+                )
             }
         }
+    }
+
+    when (dialog) {
+        SettingsDialog.Bitrate -> {
+            ChoiceDialog(
+                title = "Maximum bitrate",
+                options = bitrateOptions.map { it to bitrateLabel(it) },
+                selected = maxBitrate,
+                onSelect = { value ->
+                    onMaxBitrateChange(value)
+                    dialog = null
+                },
+                onDismiss = { dialog = null },
+            )
+        }
+
+        SettingsDialog.Format -> {
+            ChoiceDialog(
+                title = "Preferred stream format",
+                options = streamFormats.map { it to (it ?: "Use server default") },
+                selected = streamFormat,
+                onSelect = { value ->
+                    onStreamFormatChange(value)
+                    dialog = null
+                },
+                onDismiss = { dialog = null },
+            )
+        }
+
+        null -> {
+            Unit
+        }
+    }
+}
+
+private fun bitrateLabel(kbps: Int): String = if (kbps == 0) "Unlimited" else "${kbps}kbps"
+
+@Composable
+private fun <T> ChoiceDialog(
+    title: String,
+    options: List<Pair<T, String>>,
+    selected: T,
+    onSelect: (T) -> Unit,
+    onDismiss: () -> Unit,
+) {
+    AlertDialog(
+        onDismissRequest = onDismiss,
+        title = { Text(title) },
+        text = {
+            Column {
+                options.forEach { (value, label) ->
+                    Row(
+                        verticalAlignment = Alignment.CenterVertically,
+                        modifier = Modifier.fillMaxWidth().clickable { onSelect(value) },
+                    ) {
+                        RadioButton(selected = value == selected, onClick = { onSelect(value) })
+                        Spacer(Modifier.width(8.dp))
+                        Text(label)
+                    }
+                }
+            }
+        },
+        confirmButton = {
+            TextButton(onClick = onDismiss) { Text("Cancel") }
+        },
+    )
 }
 
 @Composable

app/src/main/kotlin/com/subtracks/ui/settings/SettingsViewModel.kt

@@ -3,6 +3,7 @@ package com.subtracks.ui.settings
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import com.subtracks.data.model.Source
+import com.subtracks.data.prefs.UserPreferences
 import com.subtracks.data.repo.SourceRepository
 import kotlinx.coroutines.flow.SharingStarted
 import kotlinx.coroutines.flow.StateFlow
@@ -11,6 +12,7 @@ import kotlinx.coroutines.launch
 
 class SettingsViewModel(
     private val sourceRepository: SourceRepository,
+    private val userPreferences: UserPreferences,
 ) : ViewModel() {
     val sources: StateFlow<List<Source>> =
         sourceRepository.sources().stateIn(viewModelScope, SharingStarted.WhileSubscribed(5_000), emptyList())
@@ -18,6 +20,14 @@ class SettingsViewModel(
     val activeSourceId: StateFlow<Long?> =
         sourceRepository.activeSourceId().stateIn(viewModelScope, SharingStarted.WhileSubscribed(5_000), null)
 
+    val maxBitrate: StateFlow<Int> =
+        userPreferences.maxBitrate
+            .stateIn(viewModelScope, SharingStarted.WhileSubscribed(5_000), 0)
+
+    val streamFormat: StateFlow<String?> =
+        userPreferences.streamFormat
+            .stateIn(viewModelScope, SharingStarted.WhileSubscribed(5_000), null)
+
     fun selectSource(id: Long) {
         viewModelScope.launch { sourceRepository.selectSource(id) }
     }
@@ -25,4 +35,12 @@ class SettingsViewModel(
     fun deleteSource(id: Long) {
         viewModelScope.launch { sourceRepository.deleteSource(id) }
     }
+
+    fun setMaxBitrate(kbps: Int) {
+        viewModelScope.launch { userPreferences.setMaxBitrate(kbps) }
+    }
+
+    fun setStreamFormat(format: String?) {
+        viewModelScope.launch { userPreferences.setStreamFormat(format) }
+    }
 }

app/src/test/kotlin/com/subtracks/data/prefs/FakeUserPreferences.kt

@@ -0,0 +1,19 @@
+package com.subtracks.data.prefs
+
+import androidx.datastore.core.DataStore
+import androidx.datastore.preferences.core.Preferences
+import androidx.datastore.preferences.core.emptyPreferences
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.MutableStateFlow
+
+fun fakeUserPreferences(): UserPreferences =
+    UserPreferences(
+        object : DataStore<Preferences> {
+            private val state = MutableStateFlow(emptyPreferences())
+
+            override val data: Flow<Preferences> = state
+
+            override suspend fun updateData(transform: suspend (Preferences) -> Preferences): Preferences =
+                transform(state.value).also { state.value = it }
+        },
+    )

app/src/test/kotlin/com/subtracks/data/repo/SourceRepositoryTest.kt

@@ -6,6 +6,7 @@ import androidx.sqlite.driver.bundled.BundledSQLiteDriver
 import androidx.test.core.app.ApplicationProvider
 import androidx.test.ext.junit.runners.AndroidJUnit4
 import com.subtracks.data.db.SubtracksDatabase
+import com.subtracks.data.prefs.fakeUserPreferences
 import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.test.runTest
 import okhttp3.OkHttpClient
@@ -28,7 +29,7 @@ class SourceRepositoryTest {
                 .inMemoryDatabaseBuilder(context, SubtracksDatabase::class.java)
                 .setDriver(BundledSQLiteDriver())
                 .build()
-        repository = SourceRepository(db, OkHttpClient())
+        repository = SourceRepository(db, OkHttpClient(), fakeUserPreferences())
     }
 
     @After

app/src/test/kotlin/com/subtracks/data/source/subsonic/SubsonicSourceTest.kt

@@ -8,6 +8,8 @@ import okhttp3.mockwebserver.MockWebServer
 import okhttp3.mockwebserver.RecordedRequest
 import org.junit.After
 import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertTrue
 import org.junit.Before
 import org.junit.Test
 
@@ -54,6 +56,31 @@ class SubsonicSourceTest {
             assertEquals(listOf("s1", "s2"), source.getSongs().map { it.id })
         }
 
+    @Test
+    fun streamUriRequestsTranscodingWhenABitrateIsSet() {
+        val uri = SubsonicSource(1, client(), maxBitrate = 128).streamUri("s1").toString()
+
+        assertTrue(uri, uri.contains("maxBitRate=128"))
+        assertTrue(uri, uri.contains("estimateContentLength=true"))
+    }
+
+    @Test
+    fun streamUriLeavesTheOriginalStreamAloneByDefault() {
+        val uri = SubsonicSource(1, client()).streamUri("s1").toString()
+
+        assertFalse(uri, uri.contains("maxBitRate"))
+        assertFalse(uri, uri.contains("format="))
+        assertFalse(uri, uri.contains("estimateContentLength"))
+    }
+
+    @Test
+    fun streamUriRequestsAPreferredFormat() {
+        val uri = SubsonicSource(1, client(), streamFormat = "opus").streamUri("s1").toString()
+
+        assertTrue(uri, uri.contains("format=opus"))
+        assertTrue(uri, uri.contains("estimateContentLength=true"))
+    }
+
     private fun client() =
         SubsonicClient(
             baseUrl = server.url("/"),

app/src/test/kotlin/com/subtracks/playback/PlaybackControllerTest.kt

@@ -10,6 +10,7 @@ import com.subtracks.data.model.QueueEntry
 import com.subtracks.data.model.QueueKind
 import com.subtracks.data.model.Song
 import com.subtracks.data.model.Source
+import com.subtracks.data.prefs.fakeUserPreferences
 import com.subtracks.data.repo.QueueRepository
 import com.subtracks.data.repo.SourceRepository
 import kotlinx.coroutines.asCoroutineDispatcher
@@ -42,7 +43,7 @@ class PlaybackControllerTest {
                 .inMemoryDatabaseBuilder(context, SubtracksDatabase::class.java)
                 .setDriver(BundledSQLiteDriver())
                 .build()
-        sources = SourceRepository(db, OkHttpClient())
+        sources = SourceRepository(db, OkHttpClient(), fakeUserPreferences())
         queues = QueueRepository(db)
         handle = FakePlayerHandle()
         controller = PlaybackController(sources, queues, FakePlayerConnection(handle), dispatcher = dispatcher)
@@ -61,7 +62,7 @@ class PlaybackControllerTest {
         seedAlbum(60, sourceId = 1)
 
         controller.playAlbum(1, "al1", 30)
-        await { handle.items.isNotEmpty() }
+        await { handle.operations.contains("play") }
 
         assertEquals(51, handle.itemCount)
         assertEquals(25, handle.currentIndex)

app/src/test/kotlin/com/subtracks/ui/AppScreenshotTest.kt

@@ -153,8 +153,12 @@ class AppScreenshotTest {
                 SettingsScreen(
                     sources = Fixtures.sources,
                     activeSourceId = 1,
+                    maxBitrate = 0,
+                    streamFormat = null,
                     onSelectSource = {},
                     onDeleteSource = {},
+                    onMaxBitrateChange = {},
+                    onStreamFormatChange = {},
                     onAddServer = {},
                     onBack = {},
                 )

docs/implementation-plan.md

@@ -33,7 +33,7 @@ Not done yet in this slice (deliberately): artist detail, cover-art tonal colour
 - (done) Media3/ExoPlayer playback service, queue and now-playing UI: a `MediaSessionService` plus a mini player and a Now Playing screen.
 - (done) Media notifications and headset/Bluetooth controls, from the media session.
 - (done) A SQL-backed queue of references (whole playlist / album / song, each with an optional ordinal range) resolved lazily, with only a bounded window in memory and in the player.
-- Streaming with `maxBitRate`/format taken from settings.
+- (done) Streaming bitrate and preferred format from settings (`maxBitRate`/`format`, so the server transcodes as configured).
 - Playing from the Songs tab, the queue view (add to queue / play next / reorder), and gapless format preferences.
 - Scrobbling and "now playing" back to the server.
 - Optional download/caching.