Handle offline mode in shelf

app/src/main/java/org/koitharu/kotatsu/core/os/NetworkStateObserver.kt

@@ -0,0 +1,64 @@
+package org.koitharu.kotatsu.core.os
+
+import android.content.Context
+import android.net.ConnectivityManager.NetworkCallback
+import android.net.Network
+import android.net.NetworkRequest
+import dagger.hilt.android.qualifiers.ApplicationContext
+import kotlinx.coroutines.channels.ProducerScope
+import kotlinx.coroutines.channels.awaitClose
+import kotlinx.coroutines.channels.trySendBlocking
+import kotlinx.coroutines.flow.FlowCollector
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.callbackFlow
+import org.koitharu.kotatsu.utils.ext.connectivityManager
+import org.koitharu.kotatsu.utils.ext.isNetworkAvailable
+import javax.inject.Inject
+import javax.inject.Singleton
+
+@Singleton
+class NetworkStateObserver @Inject constructor(
+	@ApplicationContext context: Context,
+) : StateFlow<Boolean> {
+
+	private val connectivityManager = context.connectivityManager
+
+	override val replayCache: List<Boolean>
+		get() = listOf(value)
+
+	override var value: Boolean = connectivityManager.isNetworkAvailable
+
+	override suspend fun collect(collector: FlowCollector<Boolean>): Nothing {
+		collector.emit(value)
+		while (true) {
+			observeImpl().collect(collector)
+		}
+	}
+
+	private fun observeImpl() = callbackFlow<Boolean> {
+		val request = NetworkRequest.Builder().build()
+		val callback = FlowNetworkCallback(this)
+		connectivityManager.registerNetworkCallback(request, callback)
+		awaitClose {
+			connectivityManager.unregisterNetworkCallback(callback)
+		}
+	}
+
+	inner class FlowNetworkCallback(
+		private val producerScope: ProducerScope<Boolean>,
+	) : NetworkCallback() {
+		override fun onAvailable(network: Network) = update()
+
+		override fun onLost(network: Network) = update()
+
+		override fun onUnavailable() = update()
+
+		private fun update() {
+			val newValue = connectivityManager.isNetworkAvailable
+			if (value != newValue) {
+				value = newValue
+				producerScope.trySendBlocking(newValue)
+			}
+		}
+	}
+}

app/src/main/java/org/koitharu/kotatsu/explore/ui/model/ExploreItem.kt

@@ -1,6 +1,5 @@
 package org.koitharu.kotatsu.explore.ui.model
 
-import android.net.Uri
 import androidx.annotation.DrawableRes
 import androidx.annotation.StringRes
 import org.koitharu.kotatsu.list.ui.model.EmptyState
@@ -73,6 +72,7 @@ sealed interface ExploreItem : ListModel {
 		}
 	}
 
+	@Deprecated("")
 	class EmptyHint(
 		@DrawableRes icon: Int,
 		@StringRes textPrimary: Int,

app/src/main/java/org/koitharu/kotatsu/list/ui/adapter/EmptyHintAD.kt

@@ -0,0 +1,23 @@
+package org.koitharu.kotatsu.list.ui.adapter
+
+import com.hannesdorfmann.adapterdelegates4.dsl.adapterDelegateViewBinding
+import org.koitharu.kotatsu.databinding.ItemEmptyCardBinding
+import org.koitharu.kotatsu.list.ui.model.EmptyHint
+import org.koitharu.kotatsu.list.ui.model.ListModel
+import org.koitharu.kotatsu.utils.ext.setTextAndVisible
+
+fun emptyHintAD(
+	listener: ListStateHolderListener,
+) = adapterDelegateViewBinding<EmptyHint, ListModel, ItemEmptyCardBinding>(
+	{ inflater, parent -> ItemEmptyCardBinding.inflate(inflater, parent, false) },
+) {
+
+	binding.buttonRetry.setOnClickListener { listener.onEmptyActionClick() }
+
+	bind {
+		binding.icon.setImageResource(item.icon)
+		binding.textPrimary.setText(item.textPrimary)
+		binding.textSecondary.setTextAndVisible(item.textSecondary)
+		binding.buttonRetry.setTextAndVisible(item.actionStringRes)
+	}
+}

app/src/main/java/org/koitharu/kotatsu/list/ui/model/EmptyHint.kt

@@ -0,0 +1,14 @@
+package org.koitharu.kotatsu.list.ui.model
+
+import androidx.annotation.DrawableRes
+import androidx.annotation.StringRes
+
+class EmptyHint(
+	@DrawableRes icon: Int,
+	@StringRes textPrimary: Int,
+	@StringRes textSecondary: Int,
+	@StringRes actionStringRes: Int,
+) : EmptyState(icon, textPrimary, textSecondary, actionStringRes) {
+
+	fun toState() = EmptyState(icon, textPrimary, textSecondary, actionStringRes)
+}

app/src/main/java/org/koitharu/kotatsu/shelf/ui/ShelfFragment.kt

@@ -1,6 +1,9 @@
 package org.koitharu.kotatsu.shelf.ui
 
+import android.content.Intent
+import android.os.Build
 import android.os.Bundle
+import android.provider.Settings
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
@@ -113,7 +116,14 @@ class ShelfFragment :
 
 	override fun onRetryClick(error: Throwable) = Unit
 
-	override fun onEmptyActionClick() = Unit
+	override fun onEmptyActionClick() {
+		val action = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
+			Settings.Panel.ACTION_INTERNET_CONNECTIVITY
+		} else {
+			Settings.ACTION_WIRELESS_SETTINGS
+		}
+		startActivity(Intent(action))
+	}
 
 	override fun onWindowInsetsChanged(insets: Insets) {
 		binding.recyclerView.updatePadding(

app/src/main/java/org/koitharu/kotatsu/shelf/ui/ShelfViewModel.kt

@@ -12,6 +12,7 @@ import org.koitharu.kotatsu.R
 import org.koitharu.kotatsu.base.ui.BaseViewModel
 import org.koitharu.kotatsu.base.ui.util.ReversibleAction
 import org.koitharu.kotatsu.core.model.FavouriteCategory
+import org.koitharu.kotatsu.core.os.NetworkStateObserver
 import org.koitharu.kotatsu.core.prefs.AppSettings
 import org.koitharu.kotatsu.core.prefs.ListMode
 import org.koitharu.kotatsu.favourites.domain.FavouritesRepository
@@ -19,6 +20,7 @@ import org.koitharu.kotatsu.history.domain.HistoryRepository
 import org.koitharu.kotatsu.history.domain.MangaWithHistory
 import org.koitharu.kotatsu.history.domain.PROGRESS_NONE
 import org.koitharu.kotatsu.list.domain.ListExtraProvider
+import org.koitharu.kotatsu.list.ui.model.EmptyHint
 import org.koitharu.kotatsu.list.ui.model.EmptyState
 import org.koitharu.kotatsu.list.ui.model.ListModel
 import org.koitharu.kotatsu.list.ui.model.LoadingState
@@ -26,6 +28,7 @@ import org.koitharu.kotatsu.list.ui.model.toErrorState
 import org.koitharu.kotatsu.list.ui.model.toGridModel
 import org.koitharu.kotatsu.list.ui.model.toUi
 import org.koitharu.kotatsu.parsers.model.Manga
+import org.koitharu.kotatsu.parsers.model.MangaSource
 import org.koitharu.kotatsu.parsers.model.SortOrder
 import org.koitharu.kotatsu.shelf.domain.ShelfRepository
 import org.koitharu.kotatsu.shelf.ui.model.ShelfSectionModel
@@ -41,17 +44,19 @@ class ShelfViewModel @Inject constructor(
 	private val favouritesRepository: FavouritesRepository,
 	private val trackingRepository: TrackingRepository,
 	private val settings: AppSettings,
+	private val networkStateObserver: NetworkStateObserver,
 ) : BaseViewModel(), ListExtraProvider {
 
 	val onActionDone = SingleLiveEvent<ReversibleAction>()
 
 	val content: LiveData<List<ListModel>> = combine(
+		networkStateObserver,
 		historyRepository.observeAllWithHistory(),
 		repository.observeLocalManga(SortOrder.UPDATED),
 		repository.observeFavourites(),
 		trackingRepository.observeUpdatedManga(),
-	) { history, local, favourites, updated ->
+	) { isConnected, history, local, favourites, updated ->
-		mapList(history, favourites, updated, local)
+		mapList(history, favourites, updated, local, isConnected)
 	}.debounce(500)
 		.catch { e ->
 			emit(listOf(e.toErrorState(canRetry = false)))
@@ -133,8 +138,10 @@ class ShelfViewModel @Inject constructor(
 		favourites: Map<FavouriteCategory, List<Manga>>,
 		updated: Map<Manga, Int>,
 		local: List<Manga>,
+		isNetworkAvailable: Boolean,
 	): List<ListModel> {
-		val result = ArrayList<ListModel>(favourites.keys.size + 2)
+		val result = ArrayList<ListModel>(favourites.keys.size + 3)
+		if (isNetworkAvailable) {
 			if (history.isNotEmpty()) {
 				mapHistory(result, history)
 			}
@@ -147,6 +154,21 @@ class ShelfViewModel @Inject constructor(
 			if (favourites.isNotEmpty()) {
 				mapFavourites(result, favourites)
 			}
+		} else {
+			result += EmptyHint(
+				icon = R.drawable.ic_empty_suggestions,
+				textPrimary = R.string.network_unavailable,
+				textSecondary = R.string.network_unavailable_hint,
+				actionStringRes = R.string.manage,
+			)
+			val offlineHistory = history.filter { it.manga.source == MangaSource.LOCAL }
+			if (offlineHistory.isNotEmpty()) {
+				mapHistory(result, offlineHistory)
+			}
+			if (local.isNotEmpty()) {
+				mapLocal(result, local)
+			}
+		}
 		if (result.isEmpty()) {
 			result += EmptyState(
 				icon = R.drawable.ic_empty_history,
@@ -154,6 +176,11 @@ class ShelfViewModel @Inject constructor(
 				textSecondary = R.string.text_shelf_holder_secondary,
 				actionStringRes = 0,
 			)
+		} else {
+			val one = result.singleOrNull()
+			if (one is EmptyHint) {
+				result[0] = one.toState()
+			}
 		}
 		return result
 	}

app/src/main/java/org/koitharu/kotatsu/shelf/ui/adapter/ShelfAdapter.kt

@@ -6,16 +6,17 @@ import androidx.recyclerview.widget.DiffUtil
 import androidx.recyclerview.widget.RecyclerView
 import coil.ImageLoader
 import com.hannesdorfmann.adapterdelegates4.AsyncListDifferDelegationAdapter
-import kotlin.jvm.internal.Intrinsics
 import org.koitharu.kotatsu.base.ui.list.SectionedSelectionController
 import org.koitharu.kotatsu.base.ui.list.fastscroll.FastScroller
-import org.koitharu.kotatsu.shelf.ui.model.ShelfSectionModel
 import org.koitharu.kotatsu.list.ui.ItemSizeResolver
+import org.koitharu.kotatsu.list.ui.adapter.emptyHintAD
 import org.koitharu.kotatsu.list.ui.adapter.emptyStateListAD
 import org.koitharu.kotatsu.list.ui.adapter.errorStateListAD
 import org.koitharu.kotatsu.list.ui.adapter.loadingFooterAD
 import org.koitharu.kotatsu.list.ui.adapter.loadingStateAD
 import org.koitharu.kotatsu.list.ui.model.ListModel
+import org.koitharu.kotatsu.shelf.ui.model.ShelfSectionModel
+import kotlin.jvm.internal.Intrinsics
 
 class ShelfAdapter(
 	lifecycleOwner: LifecycleOwner,
@@ -40,6 +41,7 @@ class ShelfAdapter(
 			)
 			.addDelegate(loadingStateAD())
 			.addDelegate(loadingFooterAD())
+			.addDelegate(emptyHintAD(listener))
 			.addDelegate(emptyStateListAD(coil, listener))
 			.addDelegate(errorStateListAD(listener))
 	}
@@ -56,6 +58,7 @@ class ShelfAdapter(
 				oldItem is ShelfSectionModel && newItem is ShelfSectionModel -> {
 					oldItem.key == newItem.key
 				}
+
 				else -> oldItem.javaClass == newItem.javaClass
 			}
 		}

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

@@ -44,6 +44,14 @@ val Context.activityManager: ActivityManager?
 val Context.connectivityManager: ConnectivityManager
 	get() = getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
 
+val ConnectivityManager.isNetworkAvailable: Boolean
+	get() = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
+		activeNetwork != null
+	} else {
+		@Suppress("DEPRECATION")
+		activeNetworkInfo?.isConnectedOrConnecting == true
+	}
+
 fun String.toUriOrNull() = if (isEmpty()) null else Uri.parse(this)
 
 suspend fun CoroutineWorker.trySetForeground(): Boolean = runCatchingCancellable {

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

@@ -393,4 +393,6 @@
 	<string name="webtoon_zoom">Webtoon zoom</string>
 	<string name="webtoon_zoom_summary">Allow zoom in/zoom out gesture in webtoon mode (beta)</string>
 	<string name="different_languages">Different languages</string>
+	<string name="network_unavailable">Network is not available</string>
+	<string name="network_unavailable_hint">Turn on Wi-Fi or mobile network to read manga online</string>
 </resources>