Schedule workers only on demand

app/src/main/kotlin/org/koitharu/kotatsu/settings/work/PeriodicWorkScheduler.kt

@@ -0,0 +1,12 @@
+package org.koitharu.kotatsu.settings.work
+
+import android.content.Context
+
+interface PeriodicWorkScheduler {
+
+	suspend fun schedule(context: Context)
+
+	suspend fun unschedule(context: Context)
+
+	suspend fun isScheduled(context: Context): Boolean
+}

app/src/main/kotlin/org/koitharu/kotatsu/settings/work/WorkScheduleManager.kt

@@ -0,0 +1,49 @@
+package org.koitharu.kotatsu.settings.work
+
+import android.content.Context
+import android.content.SharedPreferences
+import dagger.hilt.android.qualifiers.ApplicationContext
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
+import org.koitharu.kotatsu.core.prefs.AppSettings
+import org.koitharu.kotatsu.core.util.ext.processLifecycleScope
+import org.koitharu.kotatsu.suggestions.ui.SuggestionsWorker
+import org.koitharu.kotatsu.tracker.work.TrackWorker
+import javax.inject.Inject
+
+class WorkScheduleManager @Inject constructor(
+	@ApplicationContext private val context: Context,
+	private val settings: AppSettings,
+) : SharedPreferences.OnSharedPreferenceChangeListener {
+
+	override fun onSharedPreferenceChanged(sharedPreferences: SharedPreferences?, key: String?) {
+		when (key) {
+			AppSettings.KEY_TRACKER_ENABLED -> updateWorker(TrackWorker, settings.isTrackerEnabled)
+			AppSettings.KEY_SUGGESTIONS -> updateWorker(SuggestionsWorker, settings.isSuggestionsEnabled)
+		}
+	}
+
+	fun init() {
+		settings.subscribe(this)
+		processLifecycleScope.launch(Dispatchers.Default) {
+			updateWorkerImpl(TrackWorker, settings.isTrackerEnabled)
+			updateWorkerImpl(SuggestionsWorker, settings.isSuggestionsEnabled)
+		}
+	}
+
+	private fun updateWorker(scheduler: PeriodicWorkScheduler, isEnabled: Boolean) {
+		processLifecycleScope.launch(Dispatchers.Default) {
+			updateWorkerImpl(scheduler, isEnabled)
+		}
+	}
+
+	private suspend fun updateWorkerImpl(scheduler: PeriodicWorkScheduler, isEnabled: Boolean) {
+		if (scheduler.isScheduled(context) != isEnabled) {
+			if (isEnabled) {
+				scheduler.schedule(context)
+			} else {
+				scheduler.unschedule(context)
+			}
+		}
+	}
+}