android/app/src/main/java/com/fabledsword/minstrel/auth/AuthStore.kt

@@ -1,5 +1,6 @@
 package com.fabledsword.minstrel.auth
 
+import com.fabledsword.minstrel.cache.audiocache.CacheSettings
 import com.fabledsword.minstrel.cache.db.dao.AuthSessionDao
 import com.fabledsword.minstrel.cache.db.entities.AuthSessionEntity
 import com.fabledsword.minstrel.di.ApplicationScope
@@ -8,6 +9,7 @@ import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.flow.asStateFlow
 import kotlinx.coroutines.launch
+import kotlinx.serialization.json.Json
 import javax.inject.Inject
 import javax.inject.Singleton
 
@@ -46,6 +48,11 @@ class AuthStore @Inject constructor(
     private val clientIdState = MutableStateFlow<String?>(null)
     val clientId: StateFlow<String?> = clientIdState.asStateFlow()
 
+    private val cacheSettingsState = MutableStateFlow(CacheSettings.DEFAULT)
+    val cacheSettings: StateFlow<CacheSettings> = cacheSettingsState.asStateFlow()
+
+    private val json = Json { ignoreUnknownKeys = true }
+
     init {
         scope.launch {
             dao.observe().collect { row ->
@@ -54,10 +61,18 @@ class AuthStore @Inject constructor(
                 userJsonState.value = row?.userJson
                 themeModeState.value = row?.themeMode
                 clientIdState.value = row?.clientId
+                cacheSettingsState.value = decodeCacheSettings(row?.cacheSettingsJson)
             }
         }
     }
 
+    private fun decodeCacheSettings(raw: String?): CacheSettings {
+        if (raw.isNullOrEmpty()) return CacheSettings.DEFAULT
+        return runCatching {
+            json.decodeFromString(CacheSettings.serializer(), raw)
+        }.getOrDefault(CacheSettings.DEFAULT)
+    }
+
     fun setSessionCookie(value: String?) {
         sessionCookieState.value = value
         scope.launch { persistCookie(value) }
@@ -83,6 +98,12 @@ class AuthStore @Inject constructor(
         scope.launch { persistClientId(value) }
     }
 
+    fun setCacheSettings(value: CacheSettings) {
+        cacheSettingsState.value = value
+        val encoded = json.encodeToString(CacheSettings.serializer(), value)
+        scope.launch { persistCacheSettings(encoded) }
+    }
+
     private suspend fun persistCookie(value: String?) {
         if (dao.get() == null) {
             dao.upsert(currentEntity().copy(sessionCookie = value))
@@ -123,6 +144,14 @@ class AuthStore @Inject constructor(
         }
     }
 
+    private suspend fun persistCacheSettings(json: String) {
+        if (dao.get() == null) {
+            dao.upsert(currentEntity().copy(cacheSettingsJson = json))
+        } else {
+            dao.setCacheSettingsJson(json)
+        }
+    }
+
     private fun currentEntity(): AuthSessionEntity = AuthSessionEntity(
         id = ROW_ID,
         sessionCookie = sessionCookieState.value,
@@ -130,6 +159,10 @@ class AuthStore @Inject constructor(
         userJson = userJsonState.value,
         themeMode = themeModeState.value,
         clientId = clientIdState.value,
+        cacheSettingsJson = json.encodeToString(
+            CacheSettings.serializer(),
+            cacheSettingsState.value,
+        ),
     )
 
     companion object {

android/app/src/main/java/com/fabledsword/minstrel/cache/audiocache/CacheSettings.kt

@@ -0,0 +1,37 @@
+package com.fabledsword.minstrel.cache.audiocache
+
+import kotlinx.serialization.Serializable
+
+private const val FIVE_GIB_BYTES = 5L * 1024 * 1024 * 1024
+private const val DEFAULT_PREFETCH_WINDOW = 5
+
+/**
+ * User-tunable audio cache settings. Mirrors Flutter's `CacheSettings`
+ * (cache_settings_provider.dart) field-for-field. Persisted as a JSON
+ * blob on the auth_session single-row table via [AuthStore].
+ *
+ * - [likedCapBytes]: budget for cached files of liked tracks. 0 means
+ *   unlimited. Effective at next app start (SimpleCache is built once
+ *   per process).
+ * - [rollingCapBytes]: budget for incidental / auto-prefetch downloads.
+ *   Same 0=unlimited / restart-to-apply caveat.
+ * - [prefetchWindow]: 1..10. Number of next-tracks the prefetcher
+ *   pre-downloads. Has no effect until the prefetcher lands (separate
+ *   audit follow-up) — persisted now so the user can pre-configure.
+ * - [cacheLikedTracks]: when true, liking a track should also pin its
+ *   audio to the liked-cache bucket. Has no effect until pin-on-like
+ *   lands (separate follow-up).
+ *
+ * Defaults match Flutter: 5 GiB per bucket, prefetch=5, cache-liked=true.
+ */
+@Serializable
+data class CacheSettings(
+    val likedCapBytes: Long = FIVE_GIB_BYTES,
+    val rollingCapBytes: Long = FIVE_GIB_BYTES,
+    val prefetchWindow: Int = DEFAULT_PREFETCH_WINDOW,
+    val cacheLikedTracks: Boolean = true,
+) {
+    companion object {
+        val DEFAULT: CacheSettings = CacheSettings()
+    }
+}

android/app/src/main/java/com/fabledsword/minstrel/cache/db/AppDatabase.kt

@@ -59,7 +59,7 @@ import com.fabledsword.minstrel.cache.db.entities.SyncMetadataEntity
         CachedHomeIndexEntity::class,
         AuthSessionEntity::class,
     ],
-    version = 4,
+    version = 5,
     exportSchema = true,
 )
 @TypeConverters(MinstrelTypeConverters::class)

android/app/src/main/java/com/fabledsword/minstrel/cache/db/dao/AuthSessionDao.kt

@@ -38,4 +38,8 @@ interface AuthSessionDao {
     /** Partial update: change only the stable client install id. */
     @Query("UPDATE auth_session SET clientId = :clientId WHERE id = 0")
     suspend fun setClientId(clientId: String?)
+
+    /** Partial update: change only the serialized cache settings. */
+    @Query("UPDATE auth_session SET cacheSettingsJson = :json WHERE id = 0")
+    suspend fun setCacheSettingsJson(json: String?)
 }

android/app/src/main/java/com/fabledsword/minstrel/cache/db/entities/AuthSessionEntity.kt

@@ -29,4 +29,11 @@ data class AuthSessionEntity(
     val userJson: String? = null,
     val themeMode: String? = null,
     val clientId: String? = null,
+    /**
+     * JSON-encoded CacheSettings (cache/audiocache/CacheSettings.kt).
+     * Null = use defaults. Stored as a JSON blob rather than four
+     * individual columns to keep schema changes cheap when the
+     * CacheSettings shape evolves.
+     */
+    val cacheSettingsJson: String? = null,
 )

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

@@ -1,5 +1,6 @@
 package com.fabledsword.minstrel.player
 
+import com.fabledsword.minstrel.auth.AuthStore
 import com.fabledsword.minstrel.cache.audiocache.CacheConfig
 import dagger.Module
 import dagger.Provides
@@ -21,7 +22,23 @@ import javax.inject.Singleton
 @InstallIn(SingletonComponent::class)
 object PlayerModule {
 
+    /**
+     * CacheConfig snapshot from the user's persisted CacheSettings.
+     * SimpleCache is constructed once per process, so changes via the
+     * Settings UI take effect on next app launch (not mid-flight).
+     * AuthStore's StateFlow hydrates async from Room — when the
+     * factory @Provides runs, the value is either the persisted
+     * setting (if Room finished first) or CacheSettings.DEFAULT.
+     * Worst case the user's tuning lands on next-next launch, which
+     * is acceptable for a single-user device pref.
+     */
     @Provides
     @Singleton
-    fun provideCacheConfig(): CacheConfig = CacheConfig()
+    fun provideCacheConfig(authStore: AuthStore): CacheConfig {
+        val s = authStore.cacheSettings.value
+        return CacheConfig(
+            likedCapBytes = s.likedCapBytes,
+            rollingCapBytes = s.rollingCapBytes,
+        )
+    }
 }