Launch animation: rocket-style play button

core/data/src/main/kotlin/dev/xitee/sleeptimer/core/data/model/UserSettings.kt

@@ -12,4 +12,5 @@ data class UserSettings(
     val starsEnabled: Boolean = true,
     val stepMinutes: Int = 5,
     val presetMinutes: Int = 15,
+    val launchAnimationEnabled: Boolean = true,
 )

core/data/src/main/kotlin/dev/xitee/sleeptimer/core/data/repository/SettingsRepository.kt

@@ -17,4 +17,5 @@ interface SettingsRepository {
     suspend fun updateStarsEnabled(enabled: Boolean)
     suspend fun updateStepMinutes(minutes: Int)
     suspend fun updatePresetMinutes(minutes: Int)
+    suspend fun updateLaunchAnimationEnabled(enabled: Boolean)
 }

core/data/src/main/kotlin/dev/xitee/sleeptimer/core/data/repository/SettingsRepositoryImpl.kt

@@ -1,21 +1,29 @@
 package dev.xitee.sleeptimer.core.data.repository
 
+import android.content.Context
 import androidx.datastore.core.DataStore
 import androidx.datastore.preferences.core.Preferences
 import androidx.datastore.preferences.core.booleanPreferencesKey
 import androidx.datastore.preferences.core.edit
 import androidx.datastore.preferences.core.intPreferencesKey
 import androidx.datastore.preferences.core.stringPreferencesKey
+import dagger.hilt.android.qualifiers.ApplicationContext
 import dev.xitee.sleeptimer.core.data.model.ThemeId
 import dev.xitee.sleeptimer.core.data.model.UserSettings
+import dev.xitee.sleeptimer.core.data.util.isSystemReduceMotionEnabled
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.SupervisorJob
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.launch
 import javax.inject.Inject
 import javax.inject.Singleton
 
 @Singleton
 class SettingsRepositoryImpl @Inject constructor(
     private val dataStore: DataStore<Preferences>,
+    @ApplicationContext private val context: Context,
 ) : SettingsRepository {
 
     private companion object {
@@ -30,6 +38,27 @@ class SettingsRepositoryImpl @Inject constructor(
         val STARS_ENABLED = booleanPreferencesKey("stars_enabled")
         val STEP_MINUTES = intPreferencesKey("step_minutes")
         val PRESET_MINUTES = intPreferencesKey("preset_minutes")
+        val LAUNCH_ANIMATION_ENABLED = booleanPreferencesKey("launch_animation_enabled")
+        val LAUNCH_ANIMATION_SEEDED = booleanPreferencesKey("launch_animation_seeded")
+    }
+
+    // Einmaliger Init-Scope. IO-Dispatcher ist angemessen für DataStore-Writes,
+    // SupervisorJob verhindert dass eine Child-Exception weitere Writes stoppt.
+    private val initScope = CoroutineScope(Dispatchers.IO + SupervisorJob())
+
+    init {
+        // Seed-on-first-install: ist der „seeded"-Flag nicht gesetzt, wird das
+        // launchAnimationEnabled-Feld einmalig basierend auf der System-Reduce-Motion-
+        // Präferenz persistiert. Danach gewinnen User-Overrides. Spätere System-Änderungen
+        // werden bewusst nicht reflektiert (siehe Spec, Out-of-Scope).
+        initScope.launch {
+            dataStore.edit { prefs ->
+                if (prefs[LAUNCH_ANIMATION_SEEDED] != true) {
+                    prefs[LAUNCH_ANIMATION_ENABLED] = !isSystemReduceMotionEnabled(context)
+                    prefs[LAUNCH_ANIMATION_SEEDED] = true
+                }
+            }
+        }
     }
 
     override val settings: Flow<UserSettings> = dataStore.data.map { prefs ->
@@ -48,6 +77,7 @@ class SettingsRepositoryImpl @Inject constructor(
             starsEnabled = prefs[STARS_ENABLED] ?: d.starsEnabled,
             stepMinutes = prefs[STEP_MINUTES] ?: d.stepMinutes,
             presetMinutes = prefs[PRESET_MINUTES] ?: d.presetMinutes,
+            launchAnimationEnabled = prefs[LAUNCH_ANIMATION_ENABLED] ?: d.launchAnimationEnabled,
         )
     }
 
@@ -94,4 +124,8 @@ class SettingsRepositoryImpl @Inject constructor(
     override suspend fun updatePresetMinutes(minutes: Int) {
         dataStore.edit { it[PRESET_MINUTES] = minutes.coerceIn(1, 300) }
     }
+
+    override suspend fun updateLaunchAnimationEnabled(enabled: Boolean) {
+        dataStore.edit { it[LAUNCH_ANIMATION_ENABLED] = enabled }
+    }
 }

core/data/src/main/kotlin/dev/xitee/sleeptimer/core/data/util/ReduceMotion.kt

@@ -0,0 +1,18 @@
+package dev.xitee.sleeptimer.core.data.util
+
+import android.content.Context
+import android.provider.Settings
+
+/**
+ * Gibt true zurück, wenn der Nutzer in den System-Einstellungen „Animationen entfernen"
+ * aktiviert hat. Erkennung über `Settings.Global.ANIMATOR_DURATION_SCALE == 0f`, was
+ * von Accessibility-Settings und den Developer-Options identisch gesetzt wird.
+ */
+fun isSystemReduceMotionEnabled(context: Context): Boolean {
+    val scale = Settings.Global.getFloat(
+        context.contentResolver,
+        Settings.Global.ANIMATOR_DURATION_SCALE,
+        1f,
+    )
+    return scale == 0f
+}