feat(prefs): app preferences over the kit's PrefStore

SettingsPrefs exposes the appearance slice; DataModule builds the DataStore on the kit's @IoDispatcher. The store is created with a corruption handler that replaces an unreadable file with empty preferences, so a truncated clockula_prefs.preferences_pb cannot leave the app crashing on every launch with no recovery short of clearing app data. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-11 12:47:26 +02:00
parent 2f2a2c529d
commit fc615e4622
4 changed files with 265 additions and 0 deletions
@@ -0,0 +1,73 @@
+package de.jeanlucmakiola.clockula.data.di
+
+import android.content.Context
+import androidx.datastore.core.DataStore
+import androidx.datastore.core.handlers.ReplaceFileCorruptionHandler
+import androidx.datastore.preferences.core.PreferenceDataStoreFactory
+import androidx.datastore.preferences.core.Preferences
+import androidx.datastore.preferences.core.emptyPreferences
+import androidx.datastore.preferences.preferencesDataStoreFile
+import dagger.Module
+import dagger.Provides
+import dagger.hilt.InstallIn
+import dagger.hilt.android.qualifiers.ApplicationContext
+import dagger.hilt.components.SingletonComponent
+import de.jeanlucmakiola.floret.di.IoDispatcher
+import de.jeanlucmakiola.floret.prefs.PrefStore
+import kotlinx.coroutines.CoroutineDispatcher
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.SupervisorJob
+import java.io.File
+import javax.inject.Singleton
+
+/**
+ * Clockula's storage bindings. M1 wires the preference half only; the Room
+ * database and its DAOs join this module in M2.
+ */
+@Module
+@InstallIn(SingletonComponent::class)
+object DataModule {
+
+    /** App-local: the store's name stays out of floret-kit, by its roadmap's rule. */
+    private const val PREFS_NAME = "clockula_prefs"
+
+    /**
+     * Built explicitly rather than through the `preferencesDataStore` delegate so
+     * the store's own coroutine scope runs on the kit's IO dispatcher.
+     * `@Singleton` gives the same one-instance-per-file guarantee the delegate
+     * exists to provide.
+     */
+    @Provides
+    @Singleton
+    fun provideDataStore(
+        @ApplicationContext context: Context,
+        @IoDispatcher io: CoroutineDispatcher,
+    ): DataStore<Preferences> = createDataStore(
+        scope = CoroutineScope(io + SupervisorJob()),
+        produceFile = { context.preferencesDataStoreFile(PREFS_NAME) },
+    )
+
+    @Provides
+    @Singleton
+    fun providePrefStore(dataStore: DataStore<Preferences>): PrefStore = PrefStore(dataStore)
+}
+
+/**
+ * The store's construction, free of [Context] so it can be exercised from a
+ * plain JVM unit test.
+ *
+ * A half-written `clockula_prefs.preferences_pb` — a kill during a write, a
+ * bad restore — otherwise throws `CorruptionException` out of
+ * `dataStore.data` on every single launch, and nothing between here and the
+ * theme catches it. Replacing an unreadable file with empty preferences
+ * costs the user their two appearance choices and keeps the app startable;
+ * the alternative is an app that can only be fixed by clearing its data.
+ */
+internal fun createDataStore(
+    scope: CoroutineScope,
+    produceFile: () -> File,
+): DataStore<Preferences> = PreferenceDataStoreFactory.create(
+    corruptionHandler = ReplaceFileCorruptionHandler { emptyPreferences() },
+    scope = scope,
+    produceFile = produceFile,
+)
@@ -0,0 +1,31 @@
+package de.jeanlucmakiola.clockula.data.prefs
+
+import de.jeanlucmakiola.floret.prefs.Appearance
+import de.jeanlucmakiola.floret.prefs.AppearancePrefs
+import de.jeanlucmakiola.floret.prefs.PrefStore
+import de.jeanlucmakiola.floret.prefs.ThemeMode
+import de.jeanlucmakiola.floret.prefs.appearance
+import kotlinx.coroutines.flow.Flow
+import javax.inject.Inject
+import javax.inject.Singleton
+
+/**
+ * Clockula's app preferences. M1 covers the appearance slice only; M2 adds the
+ * clock defaults and the stopwatch running state to this same class.
+ */
+@Singleton
+class SettingsPrefs @Inject constructor(private val store: PrefStore) {
+
+    // Built once, not per access: a collector keyed on the flow instance (as
+    // `collectAsStateWithLifecycle` is) would otherwise tear down and restart
+    // the DataStore collection on every recomposition.
+    val appearance: Flow<Appearance> = store.appearance()
+
+    val themeMode: Flow<ThemeMode> = store.flow(AppearancePrefs.themeMode)
+
+    val dynamicColor: Flow<Boolean> = store.flow(AppearancePrefs.dynamicColor)
+
+    suspend fun setThemeMode(mode: ThemeMode) = store.set(AppearancePrefs.themeMode, mode)
+
+    suspend fun setDynamicColor(enabled: Boolean) = store.set(AppearancePrefs.dynamicColor, enabled)
+}