Option to control pages preloading

app/src/main/java/org/koitharu/kotatsu/core/prefs/AppSettings.kt

@@ -2,6 +2,7 @@ package org.koitharu.kotatsu.core.prefs
 
 import android.content.Context
 import android.content.SharedPreferences
+import android.net.ConnectivityManager
 import android.net.Uri
 import android.os.Build
 import android.provider.Settings
@@ -141,6 +142,14 @@ class AppSettings(context: Context) {
 			}
 		}
 
+	fun isPagesPreloadAllowed(cm: ConnectivityManager): Boolean {
+		return when (prefs.getString(KEY_PAGES_PRELOAD, null)?.toIntOrNull()) {
+			NETWORK_ALWAYS -> true
+			NETWORK_NEVER -> false
+			else -> cm.isActiveNetworkMetered
+		}
+	}
+
 	fun getDateFormat(format: String = prefs.getString(KEY_DATE_FORMAT, "").orEmpty()): DateFormat =
 		when (format) {
 			"" -> DateFormat.getDateInstance(DateFormat.SHORT)
@@ -231,6 +240,7 @@ class AppSettings(context: Context) {
 		const val KEY_HISTORY_EXCLUDE_NSFW = "history_exclude_nsfw"
 		const val KEY_PAGES_NUMBERS = "pages_numbers"
 		const val KEY_SCREENSHOTS_POLICY = "screenshots_policy"
+		const val KEY_PAGES_PRELOAD = "pages_preload"
 
 		// About
 		const val KEY_APP_UPDATE = "app_update"
@@ -242,6 +252,10 @@ class AppSettings(context: Context) {
 		const val KEY_FEEDBACK_GITHUB = "about_feedback_github"
 		const val KEY_SUPPORT_DEVELOPER = "about_support_developer"
 
+		private const val NETWORK_NEVER = 0
+		private const val NETWORK_ALWAYS = 1
+		private const val NETWORK_NON_METERED = 2
+
 		val isDynamicColorAvailable: Boolean
 			get() = DynamicColors.isDynamicColorAvailable() ||
 				(isSamsung && Build.VERSION.SDK_INT >= Build.VERSION_CODES.S)

app/src/main/java/org/koitharu/kotatsu/download/ui/service/DownloadService.kt

@@ -4,7 +4,6 @@ import android.content.BroadcastReceiver
 import android.content.Context
 import android.content.Intent
 import android.content.IntentFilter
-import android.net.ConnectivityManager
 import android.os.Binder
 import android.os.IBinder
 import android.os.PowerManager
@@ -31,6 +30,7 @@ import org.koitharu.kotatsu.base.ui.dialog.CheckBoxAlertDialog
 import org.koitharu.kotatsu.core.model.Manga
 import org.koitharu.kotatsu.core.prefs.AppSettings
 import org.koitharu.kotatsu.download.domain.DownloadManager
+import org.koitharu.kotatsu.utils.ext.connectivityManager
 import org.koitharu.kotatsu.utils.ext.toArraySet
 import org.koitharu.kotatsu.utils.progress.ProgressJob
 import java.util.concurrent.TimeUnit
@@ -183,9 +183,8 @@ class DownloadService : BaseService() {
 			.putExtra(ACTION_DOWNLOAD_CANCEL, startId)
 
 		private fun confirmDataTransfer(context: Context, callback: () -> Unit) {
-			val cm = context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
 			val settings = GlobalContext.get().get<AppSettings>()
-			if (cm.isActiveNetworkMetered && settings.isTrafficWarningEnabled) {
+			if (context.connectivityManager.isActiveNetworkMetered && settings.isTrafficWarningEnabled) {
 				CheckBoxAlertDialog.Builder(context)
 					.setTitle(R.string.warning)
 					.setMessage(R.string.network_consumption_warning)

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

@@ -1,5 +1,6 @@
 package org.koitharu.kotatsu.reader.domain
 
+import android.content.Context
 import android.graphics.Bitmap
 import android.graphics.BitmapFactory
 import android.net.Uri
@@ -20,9 +21,11 @@ import org.koitharu.kotatsu.core.model.MangaSource
 import org.koitharu.kotatsu.core.network.CommonHeaders
 import org.koitharu.kotatsu.core.parser.MangaRepository
 import org.koitharu.kotatsu.core.parser.RemoteMangaRepository
+import org.koitharu.kotatsu.core.prefs.AppSettings
 import org.koitharu.kotatsu.local.data.PagesCache
 import org.koitharu.kotatsu.reader.ui.pager.ReaderPage
 import org.koitharu.kotatsu.utils.ext.await
+import org.koitharu.kotatsu.utils.ext.connectivityManager
 import org.koitharu.kotatsu.utils.ext.mangaRepositoryOf
 import org.koitharu.kotatsu.utils.progress.ProgressDeferred
 import java.io.File
@@ -39,6 +42,8 @@ class PageLoader : KoinComponent, Closeable {
 
 	private val okHttp = get<OkHttpClient>()
 	private val cache = get<PagesCache>()
+	private val settings = get<AppSettings>()
+	private val connectivityManager = get<Context>().connectivityManager
 	private val tasks = LongSparseArray<ProgressDeferred<File, Float>>()
 	private val convertLock = Mutex()
 	private var repository: MangaRepository? = null
@@ -53,7 +58,7 @@ class PageLoader : KoinComponent, Closeable {
 	}
 
 	fun isPrefetchApplicable(): Boolean {
-		return repository is RemoteMangaRepository
+		return repository is RemoteMangaRepository && settings.isPagesPreloadAllowed(connectivityManager)
 	}
 
 	fun prefetch(pages: List<ReaderPage>) {

app/src/main/java/org/koitharu/kotatsu/utils/ext/AndroidExt.kt

@@ -11,6 +11,9 @@ import com.google.android.material.dialog.MaterialAlertDialogBuilder
 import kotlinx.coroutines.suspendCancellableCoroutine
 import kotlin.coroutines.resume
 
+val Context.connectivityManager: ConnectivityManager
+	get() = getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
+
 suspend fun ConnectivityManager.waitForNetwork(): Network {
 	val request = NetworkRequest.Builder().build()
 	return suspendCancellableCoroutine<Network> { cont ->

app/src/main/res/values/arrays.xml

@@ -29,4 +29,9 @@
 		<item>@string/screenshots_block_nsfw</item>
 		<item>@string/screenshots_block_all</item>
 	</string-array>
+	<string-array name="network_policy">
+		<item>@string/always</item>
+		<item>@string/only_using_wifi</item>
+		<item>@string/never</item>
+	</string-array>
 </resources>

app/src/main/res/values/constants.xml

@@ -25,4 +25,9 @@
 		<item>block_nsfw</item>
 		<item>block_all</item>
 	</string-array>
+	<string-array name="values_network_policy">
+		<item>1</item>
+		<item>2</item>
+		<item>0</item>
+	</string-array>
 </resources>

app/src/main/res/values/strings.xml

@@ -255,4 +255,8 @@
 	<string name="screenshots_allow">Allow</string>
 	<string name="screenshots_block_nsfw">Block on NSFW</string>
 	<string name="screenshots_block_all">Block always</string>
+	<string name="never">Never</string>
+	<string name="only_using_wifi">Only using WiFi</string>
+	<string name="always">Always</string>
+	<string name="preload_pages">Preload pages</string>
 </resources>

app/src/main/res/xml/pref_reader.xml

@@ -47,4 +47,13 @@
 		app:iconSpaceReserved="false"
 		app:useSimpleSummaryProvider="true" />
 
+	<ListPreference
+		android:entries="@array/network_policy"
+		android:entryValues="@array/values_network_policy"
+		android:key="pages_preload"
+		android:title="@string/preload_pages"
+		app:defaultValue="2"
+		app:iconSpaceReserved="false"
+		app:useSimpleSummaryProvider="true" />
+
 </PreferenceScreen>