pager: do not skip next batch if current batch yields no valid apps

app/src/main/java/com/aurora/store/data/PageResult.kt

@@ -0,0 +1,11 @@
+/*
+ * SPDX-FileCopyrightText: 2025 Aurora OSS
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+package com.aurora.store.data
+
+data class PageResult<T>(
+    val items: List<T>,
+    val hasMore: Boolean = items.isNotEmpty()
+)

app/src/main/java/com/aurora/store/data/paging/GenericPagingSource.kt

@@ -10,6 +10,7 @@ import androidx.paging.PagingConfig
 import androidx.paging.PagingSource
 import androidx.paging.PagingSource.LoadResult.Page.Companion.COUNT_UNDEFINED
 import androidx.paging.PagingState
+import com.aurora.store.data.PageResult
 import com.aurora.store.data.paging.GenericPagingSource.Companion.manualPager
 import com.aurora.store.data.paging.GenericPagingSource.Companion.pager
 import kotlinx.coroutines.Dispatchers
@@ -23,7 +24,7 @@ import kotlinx.coroutines.withContext
  * @param block Data to load into the pager
  */
 class GenericPagingSource<T : Any>(
-    private val block: suspend (Int) -> List<T>
+    private val block: suspend (Int) -> PageResult<T>
 ) : PagingSource<Int, T>() {
 
     companion object {
@@ -54,7 +55,7 @@ class GenericPagingSource<T : Any>(
         fun <T : Any> manualPager(
             pageSize: Int = DEFAULT_PAGE_SIZE,
             enablePlaceholders: Boolean = true,
-            data: suspend (Int) -> List<T>
+            data: suspend (Int) -> PageResult<T>
         ): Pager<Int, T> = Pager(
             config = PagingConfig(enablePlaceholders = enablePlaceholders, pageSize = pageSize),
             pagingSourceFactory = { GenericPagingSource(data) }
@@ -65,12 +66,12 @@ class GenericPagingSource<T : Any>(
         val page = params.key ?: 1
         return try {
             withContext(Dispatchers.IO) {
-                val data = block(page)
+                val result = block(page)
                 LoadResult.Page(
-                    data = data,
+                    data = result.items,
                     prevKey = if (page == 1) null else page - 1,
-                    nextKey = if (data.isEmpty()) null else page + 1,
+                    nextKey = if (result.hasMore) page + 1 else null,
-                    itemsAfter = if (data.isEmpty()) 0 else COUNT_UNDEFINED
+                    itemsAfter = if (result.hasMore) COUNT_UNDEFINED else 0
                 )
             }
         } catch (exception: Exception) {

app/src/main/java/com/aurora/store/viewmodel/all/InstalledViewModel.kt

@@ -20,14 +20,13 @@
 package com.aurora.store.viewmodel.all
 
 import android.content.Context
-import android.util.Log
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import androidx.paging.PagingData
 import androidx.paging.cachedIn
-import com.aurora.extensions.TAG
 import com.aurora.gplayapi.data.models.App
 import com.aurora.gplayapi.helpers.web.WebAppDetailsHelper
+import com.aurora.store.data.PageResult
 import com.aurora.store.data.paging.GenericPagingSource.Companion.manualPager
 import com.aurora.store.data.providers.BlacklistProvider
 import com.aurora.store.util.PackageUtil
@@ -63,14 +62,11 @@ class InstalledViewModel @Inject constructor(
             .chunked(20)
 
         manualPager { page ->
-            try {
+            // page is 1-indexed, but list is 0-indexed
-                // page is 1-indexed, but list is 0-indexed
+            val chunk = pagedPackages.getOrNull(page - 1)
-                val chunk = pagedPackages.getOrNull(page - 1) ?: return@manualPager emptyList()
+                ?: return@manualPager PageResult(emptyList<App>(), hasMore = false)
-                webAppDetailsHelper.getAppDetails(chunk.map { it.packageName })
+            val items = webAppDetailsHelper.getAppDetails(chunk.map { it.packageName })
-            } catch (exception: Exception) {
+            PageResult(items, hasMore = page < pagedPackages.size)
-                Log.e(TAG, "Failed to fetch apps", exception)
-                emptyList()
-            }
         }.flow.distinctUntilChanged()
             .cachedIn(viewModelScope)
             .onEach { _apps.value = it }

app/src/main/java/com/aurora/store/viewmodel/browse/StreamBrowseViewModel.kt

@@ -28,6 +28,7 @@ import com.aurora.extensions.TAG
 import com.aurora.gplayapi.data.models.App
 import com.aurora.gplayapi.data.models.StreamCluster
 import com.aurora.gplayapi.helpers.web.WebStreamHelper
+import com.aurora.store.data.PageResult
 import com.aurora.store.data.paging.GenericPagingSource.Companion.manualPager
 import dagger.assisted.Assisted
 import dagger.assisted.AssistedFactory
@@ -61,7 +62,7 @@ class StreamBrowseViewModel @AssistedInject constructor(
         var nextPageUrl: String = streamCluster.clusterNextPageUrl
 
         manualPager { page ->
-            try {
+            val items = try {
                 when (page) {
                     1 -> streamCluster.clusterAppList
 
@@ -79,6 +80,7 @@ class StreamBrowseViewModel @AssistedInject constructor(
                 Log.e(TAG, "Failed to fetch apps for $page: $nextPageUrl", exception)
                 emptyList()
             }
+            PageResult(items)
         }.flow.distinctUntilChanged()
             .cachedIn(viewModelScope)
             .onEach { _apps.value = it }

app/src/main/java/com/aurora/store/viewmodel/details/ReviewViewModel.kt

@@ -13,6 +13,7 @@ import androidx.paging.cachedIn
 import com.aurora.extensions.TAG
 import com.aurora.gplayapi.data.models.Review
 import com.aurora.gplayapi.helpers.ReviewsHelper
+import com.aurora.store.data.PageResult
 import com.aurora.store.data.paging.GenericPagingSource.Companion.manualPager
 import dagger.assisted.Assisted
 import dagger.assisted.AssistedFactory
@@ -46,7 +47,7 @@ class ReviewViewModel @AssistedInject constructor(
         var reviewsNextPageUrl: String? = null
 
         manualPager { page ->
-            try {
+            val items = try {
                 when (page) {
                     1 -> reviewsHelper.getReviews(packageName, filter).also {
                         reviewsNextPageUrl = it.nextPageUrl
@@ -66,6 +67,7 @@ class ReviewViewModel @AssistedInject constructor(
                 Log.e(TAG, "Failed to fetch reviews for $page: $reviewsNextPageUrl", exception)
                 emptyList()
             }
+            PageResult(items)
         }.flow.distinctUntilChanged()
             .cachedIn(viewModelScope)
             .onEach { _reviews.value = it }

app/src/main/java/com/aurora/store/viewmodel/search/SearchViewModel.kt

@@ -20,6 +20,7 @@ import com.aurora.gplayapi.data.models.StreamCluster
 import com.aurora.gplayapi.helpers.SearchHelper
 import com.aurora.gplayapi.helpers.contracts.SearchContract
 import com.aurora.gplayapi.helpers.web.WebSearchHelper
+import com.aurora.store.data.PageResult
 import com.aurora.store.data.model.SearchFilter
 import com.aurora.store.data.paging.GenericPagingSource.Companion.manualPager
 import com.aurora.store.data.providers.AuthProvider
@@ -80,7 +81,7 @@ class SearchViewModel @Inject constructor(
         }.distinctBy { app -> app.packageName }
 
         manualPager { page ->
-            try {
+            val items = try {
                 when (page) {
                     1 -> contract.searchResults(query)
                         .also { nextBundleUrl = it.streamNextPageUrl }
@@ -110,6 +111,7 @@ class SearchViewModel @Inject constructor(
                 Log.e(TAG, "Failed to search results for $query", exception)
                 emptyList()
             }
+            PageResult(items)
         }.flow.distinctUntilChanged()
             .cachedIn(viewModelScope)
             .onEach { _apps.value = it }