Respect system PowerSave mode

app/src/main/kotlin/org/koitharu/kotatsu/core/util/ext/Android.kt

@@ -6,6 +6,7 @@ import android.app.ActivityManager.MemoryInfo
 import android.app.ActivityOptions
 import android.content.Context
 import android.content.Context.ACTIVITY_SERVICE
+import android.content.Context.POWER_SERVICE
 import android.content.ContextWrapper
 import android.content.OperationApplicationException
 import android.content.SharedPreferences
@@ -17,6 +18,7 @@ import android.graphics.Color
 import android.net.Uri
 import android.os.Build
 import android.os.Bundle
+import android.os.PowerManager
 import android.provider.Settings
 import android.view.View
 import android.view.ViewPropertyAnimator
@@ -51,6 +53,9 @@ import kotlin.math.roundToLong
 val Context.activityManager: ActivityManager?
 	get() = getSystemService(ACTIVITY_SERVICE) as? ActivityManager
 
+val Context.powerManager: PowerManager?
+	get() = getSystemService(POWER_SERVICE) as? PowerManager
+
 fun String.toUriOrNull() = if (isEmpty()) null else Uri.parse(this)
 
 suspend fun CoroutineWorker.trySetForeground(): Boolean = runCatchingCancellable {
@@ -141,6 +146,10 @@ fun Context.isLowRamDevice(): Boolean {
 	return activityManager?.isLowRamDevice ?: false
 }
 
+fun Context.isPowerSaveMode(): Boolean {
+	return powerManager?.isPowerSaveMode == true
+}
+
 val Context.ramAvailable: Long
 	get() {
 		val result = MemoryInfo()

app/src/main/kotlin/org/koitharu/kotatsu/details/service/MangaPrefetchService.kt

@@ -10,12 +10,13 @@ import org.koitharu.kotatsu.core.model.parcelable.ParcelableMangaChapters
 import org.koitharu.kotatsu.core.parser.MangaRepository
 import org.koitharu.kotatsu.core.ui.CoroutineIntentService
 import org.koitharu.kotatsu.core.util.ext.getParcelableExtraCompat
+import org.koitharu.kotatsu.core.util.ext.isPowerSaveMode
+import org.koitharu.kotatsu.core.util.ext.printStackTraceDebug
 import org.koitharu.kotatsu.history.data.HistoryRepository
 import org.koitharu.kotatsu.parsers.model.Manga
 import org.koitharu.kotatsu.parsers.model.MangaChapter
 import org.koitharu.kotatsu.parsers.model.MangaSource
 import org.koitharu.kotatsu.parsers.util.runCatchingCancellable
-import org.koitharu.kotatsu.core.util.ext.printStackTraceDebug
 import javax.inject.Inject
 
 @AndroidEntryPoint
@@ -115,6 +116,9 @@ class MangaPrefetchService : CoroutineIntentService() {
 			if (source == MangaSource.LOCAL) {
 				return false
 			}
+			if (context.isPowerSaveMode()) {
+				return false
+			}
 			val entryPoint = EntryPointAccessors.fromApplication(context, PrefetchCompanionEntryPoint::class.java)
 			return entryPoint.contentCache.isCachingEnabled && entryPoint.settings.isContentPrefetchEnabled
 		}

app/src/main/kotlin/org/koitharu/kotatsu/reader/domain/PageLoader.kt

@@ -34,6 +34,8 @@ import org.koitharu.kotatsu.core.util.FileSize
 import org.koitharu.kotatsu.core.util.RetainedLifecycleCoroutineScope
 import org.koitharu.kotatsu.core.util.ext.ensureSuccess
 import org.koitharu.kotatsu.core.util.ext.isNotEmpty
+import org.koitharu.kotatsu.core.util.ext.isPowerSaveMode
+import org.koitharu.kotatsu.core.util.ext.printStackTraceDebug
 import org.koitharu.kotatsu.core.util.ext.ramAvailable
 import org.koitharu.kotatsu.core.util.ext.withProgress
 import org.koitharu.kotatsu.core.util.progress.ProgressDeferred
@@ -42,7 +44,6 @@ import org.koitharu.kotatsu.local.data.PagesCache
 import org.koitharu.kotatsu.parsers.model.MangaPage
 import org.koitharu.kotatsu.parsers.model.MangaSource
 import org.koitharu.kotatsu.reader.ui.pager.ReaderPage
-import org.koitharu.kotatsu.core.util.ext.printStackTraceDebug
 import java.io.File
 import java.util.LinkedList
 import java.util.concurrent.atomic.AtomicInteger
@@ -83,7 +84,10 @@ class PageLoader @Inject constructor(
 	}
 
 	fun isPrefetchApplicable(): Boolean {
-		return repository is RemoteMangaRepository && settings.isPagesPreloadEnabled && !isLowRam()
+		return repository is RemoteMangaRepository
+			&& settings.isPagesPreloadEnabled
+			&& !context.isPowerSaveMode()
+			&& !isLowRam()
 	}
 
 	@AnyThread

app/src/main/kotlin/org/koitharu/kotatsu/settings/tracker/TrackerSettingsFragment.kt

@@ -24,6 +24,7 @@ import org.koitharu.kotatsu.R
 import org.koitharu.kotatsu.core.prefs.AppSettings
 import org.koitharu.kotatsu.core.ui.BasePreferenceFragment
 import org.koitharu.kotatsu.core.util.ext.observe
+import org.koitharu.kotatsu.core.util.ext.powerManager
 import org.koitharu.kotatsu.settings.tracker.categories.TrackerCategoriesConfigSheet
 import org.koitharu.kotatsu.settings.utils.MultiSummaryProvider
 import org.koitharu.kotatsu.tracker.work.TrackerNotificationChannels
@@ -155,7 +156,7 @@ class TrackerSettingsFragment :
 			return
 		}
 		val packageName = context.packageName
-		val powerManager = context.getSystemService(Context.POWER_SERVICE) as PowerManager
+		val powerManager = context.powerManager ?: return
 		if (!powerManager.isIgnoringBatteryOptimizations(packageName)) {
 			try {
 				val intent = Intent(