android/app/src/main/java/com/fabledsword/minstrel/cache/audio_cache/CacheConfig.kt

@@ -0,0 +1,23 @@
+package com.fabledsword.minstrel.cache.audio_cache
+
+/**
+ * Defaults for the 2-bucket audio cache. Matches the Flutter client.
+ *
+ *  - `likedCapBytes`: cap for the protected bucket — cached files for
+ *    tracks the user has liked. Evicted only after the rolling bucket
+ *    is fully drained (almost never under normal use).
+ *  - `rollingCapBytes`: cap for the unprotected bucket — incidental /
+ *    auto-prefetch downloads. LRU within this bucket.
+ *
+ * Phase 11 (Settings) will allow user overrides; the values are kept
+ * generous so first-time installs work well without configuration.
+ */
+data class CacheConfig(
+    val likedCapBytes: Long = DEFAULT_LIKED_CAP_BYTES,
+    val rollingCapBytes: Long = DEFAULT_ROLLING_CAP_BYTES,
+) {
+    companion object {
+        const val DEFAULT_LIKED_CAP_BYTES: Long = 200L * 1024 * 1024 // 200 MiB
+        const val DEFAULT_ROLLING_CAP_BYTES: Long = 150L * 1024 * 1024 // 150 MiB
+    }
+}

android/app/src/main/java/com/fabledsword/minstrel/player/PlayerFactory.kt

@@ -0,0 +1,74 @@
+package com.fabledsword.minstrel.player
+
+import android.content.Context
+import androidx.media3.common.AudioAttributes
+import androidx.media3.common.C
+import androidx.media3.database.StandaloneDatabaseProvider
+import androidx.media3.datasource.cache.CacheDataSink
+import androidx.media3.datasource.cache.CacheDataSource
+import androidx.media3.datasource.cache.LeastRecentlyUsedCacheEvictor
+import androidx.media3.datasource.cache.SimpleCache
+import androidx.media3.datasource.okhttp.OkHttpDataSource
+import androidx.media3.exoplayer.ExoPlayer
+import androidx.media3.exoplayer.source.DefaultMediaSourceFactory
+import com.fabledsword.minstrel.cache.audio_cache.CacheConfig
+import dagger.hilt.android.qualifiers.ApplicationContext
+import okhttp3.OkHttpClient
+import java.io.File
+import javax.inject.Inject
+import javax.inject.Singleton
+
+/**
+ * Builds the process-singleton ExoPlayer with our shared OkHttp +
+ * SimpleCache chain. The MinstrelPlayerService (Phase 6.2) calls
+ * `build()` once during onCreate.
+ *
+ * `simpleCache` is exposed as a val so the AudioCacheEvictionWorker
+ * (Phase 12.3) can call `cache.removeSpan(...)` when evicting tracks
+ * to disk-clear their cached spans.
+ *
+ * The default `LeastRecentlyUsedCacheEvictor` provides the floor LRU
+ * (sizeBytes cap = rollingCap); our policy layer in the worker layers
+ * the 2-bucket protection on top by feeding `removeSpan` only for
+ * unprotected tracks.
+ */
+@Singleton
+class PlayerFactory @Inject constructor(
+    @ApplicationContext private val context: Context,
+    private val okHttpClient: OkHttpClient,
+    private val cacheConfig: CacheConfig,
+) {
+    private val cacheDir: File = File(context.cacheDir, "audio_cache").apply { mkdirs() }
+
+    val simpleCache: SimpleCache = SimpleCache(
+        cacheDir,
+        LeastRecentlyUsedCacheEvictor(cacheConfig.rollingCapBytes),
+        StandaloneDatabaseProvider(context),
+    )
+
+    fun build(): ExoPlayer {
+        val httpDataSource = OkHttpDataSource.Factory(okHttpClient)
+        val cacheDataSource = CacheDataSource.Factory()
+            .setCache(simpleCache)
+            .setUpstreamDataSourceFactory(httpDataSource)
+            .setCacheWriteDataSinkFactory(
+                CacheDataSink.Factory()
+                    .setCache(simpleCache)
+                    .setFragmentSize(C.LENGTH_UNSET.toLong()),
+            )
+        val mediaSourceFactory = DefaultMediaSourceFactory(context)
+            .setDataSourceFactory(cacheDataSource)
+
+        return ExoPlayer.Builder(context)
+            .setMediaSourceFactory(mediaSourceFactory)
+            .setAudioAttributes(
+                AudioAttributes.Builder()
+                    .setUsage(C.USAGE_MEDIA)
+                    .setContentType(C.AUDIO_CONTENT_TYPE_MUSIC)
+                    .build(),
+                /* handleAudioFocus = */ true,
+            )
+            .setHandleAudioBecomingNoisy(true)
+            .build()
+    }
+}

android/app/src/main/java/com/fabledsword/minstrel/player/PlayerModule.kt

@@ -0,0 +1,27 @@
+package com.fabledsword.minstrel.player
+
+import com.fabledsword.minstrel.cache.audio_cache.CacheConfig
+import dagger.Module
+import dagger.Provides
+import dagger.hilt.InstallIn
+import dagger.hilt.components.SingletonComponent
+import javax.inject.Singleton
+
+/**
+ * Player + audio-cache wiring. PlayerFactory has @Inject so it doesn't
+ * need a @Provides here; this module exists to provide the
+ * configuration values (CacheConfig) it depends on, and any future
+ * player-related singletons that aren't @Inject-constructible.
+ *
+ * MinstrelPlayerService (Phase 6.2) injects PlayerFactory and calls
+ * `build()` from `onCreate`. The eviction worker (Phase 12.3) injects
+ * PlayerFactory too and reads `simpleCache` from it.
+ */
+@Module
+@InstallIn(SingletonComponent::class)
+object PlayerModule {
+
+    @Provides
+    @Singleton
+    fun provideCacheConfig(): CacheConfig = CacheConfig()
+}

android/gradle/libs.versions.toml

@@ -21,7 +21,7 @@ kotlinx-serialization = "1.7.3"
 kotlinx-coroutines = "1.9.0"
 kotlinx-datetime = "0.6.1"
 kotlinx-serialization-converter = "1.0.0"
-media3 = "1.4.1"
+media3 = "1.10.1"
 coil = "3.0.0-rc02"
 timber = "5.0.1"
 work = "2.10.0"