Add timestamp to trigger back pagination.

libraries/mediaviewer/impl/src/main/kotlin/io/element/android/libraries/mediaviewer/impl/viewer/MediaViewerDataSource.kt

@@ -27,6 +27,7 @@ import io.element.android.libraries.mediaviewer.impl.gallery.eventId
 import io.element.android.libraries.mediaviewer.impl.gallery.mediaInfo
 import io.element.android.libraries.mediaviewer.impl.gallery.mediaSource
 import io.element.android.libraries.mediaviewer.impl.gallery.thumbnailSource
+import io.element.android.services.toolbox.api.systemclock.SystemClock
 import kotlinx.collections.immutable.PersistentList
 import kotlinx.collections.immutable.persistentListOf
 import kotlinx.collections.immutable.toPersistentList
@@ -42,6 +43,7 @@ class MediaViewerDataSource(
     private val galleryDataSource: MediaGalleryDataSource,
     private val mediaLoader: MatrixMediaLoader,
     private val localMediaFactory: LocalMediaFactory,
+    private val systemClock: SystemClock,
 ) {
     // List of media files that are currently being loaded
     private val mediaFiles: MutableList<MediaFile> = mutableListOf()
@@ -108,12 +110,20 @@ class MediaViewerDataSource(
                     )
                 }
                 is MediaItem.LoadingIndicator -> add(
-                    MediaViewerPageData.Loading(mediaItem.direction)
+                    MediaViewerPageData.Loading(
+                        direction = mediaItem.direction,
+                        timestamp = systemClock.epochMillis(),
+                    )
                 )
             }
         }
         if (isEmpty()) {
-            add(MediaViewerPageData.Loading(Timeline.PaginationDirection.BACKWARDS))
+            add(
+                MediaViewerPageData.Loading(
+                    direction = Timeline.PaginationDirection.BACKWARDS,
+                    timestamp = systemClock.epochMillis(),
+                )
+            )
         }
     }.toPersistentList()
 

libraries/mediaviewer/impl/src/main/kotlin/io/element/android/libraries/mediaviewer/impl/viewer/MediaViewerNode.kt

@@ -27,6 +27,7 @@ import io.element.android.libraries.mediaviewer.api.local.LocalMediaFactory
 import io.element.android.libraries.mediaviewer.impl.gallery.MediaGalleryMode
 import io.element.android.libraries.mediaviewer.impl.gallery.SingleMediaGalleryDataSource
 import io.element.android.libraries.mediaviewer.impl.gallery.TimelineMediaGalleryDataSource
+import io.element.android.services.toolbox.api.systemclock.SystemClock
 
 @ContributesNode(RoomScope::class)
 class MediaViewerNode @AssistedInject constructor(
@@ -37,6 +38,7 @@ class MediaViewerNode @AssistedInject constructor(
     mediaLoader: MatrixMediaLoader,
     localMediaFactory: LocalMediaFactory,
     coroutineDispatchers: CoroutineDispatchers,
+    systemClock: SystemClock,
 ) : Node(buildContext, plugins = plugins),
     MediaViewerNavigator {
     private val inputs = inputs<MediaViewerEntryPoint.Params>()
@@ -77,7 +79,8 @@ class MediaViewerNode @AssistedInject constructor(
             galleryMode = galleryMode,
             galleryDataSource = mediaGallerySource,
             mediaLoader = mediaLoader,
-            localMediaFactory = localMediaFactory
+            localMediaFactory = localMediaFactory,
+            systemClock = systemClock,
         )
     )
 

libraries/mediaviewer/impl/src/main/kotlin/io/element/android/libraries/mediaviewer/impl/viewer/MediaViewerState.kt

@@ -34,6 +34,7 @@ sealed interface MediaViewerPageData {
 
     data class Loading(
         val direction: Timeline.PaginationDirection,
+        val timestamp: Long,
     ) : MediaViewerPageData
 
     data class MediaViewerData(

libraries/mediaviewer/impl/src/main/kotlin/io/element/android/libraries/mediaviewer/impl/viewer/MediaViewerStateProvider.kt

@@ -151,7 +151,7 @@ open class MediaViewerStateProvider : PreviewParameterProvider<MediaViewerState>
             },
             aMediaViewerState(
                 listOf(
-                    MediaViewerPageData.Loading(Timeline.PaginationDirection.BACKWARDS)
+                    aMediaViewerPageDataLoading()
                 ),
             ),
             aMediaViewerState(
@@ -162,6 +162,16 @@ open class MediaViewerStateProvider : PreviewParameterProvider<MediaViewerState>
         )
 }
 
+fun aMediaViewerPageDataLoading(
+    direction: Timeline.PaginationDirection = Timeline.PaginationDirection.BACKWARDS,
+    timestamp: Long = 0L,
+): MediaViewerPageData {
+    return MediaViewerPageData.Loading(
+        direction = direction,
+        timestamp = timestamp,
+    )
+}
+
 fun aMediaViewerPageData(
     downloadedMedia: AsyncData<LocalMedia> = AsyncData.Uninitialized,
     mediaInfo: MediaInfo = anImageMediaInfo(),

libraries/mediaviewer/impl/src/main/kotlin/io/element/android/libraries/mediaviewer/impl/viewer/MediaViewerView.kt

@@ -128,7 +128,7 @@ fun MediaViewerView(
                     )
                 }
                 is MediaViewerPageData.Loading -> {
-                    LaunchedEffect(Unit) {
+                    LaunchedEffect(dataForPage.timestamp) {
                         state.eventSink(MediaViewerEvents.LoadMore(dataForPage.direction))
                     }
                     MediaViewerLoadingPage(

libraries/mediaviewer/impl/src/test/kotlin/io/element/android/libraries/mediaviewer/impl/viewer/MediaViewerDataSourceTest.kt

@@ -27,6 +27,8 @@ import io.element.android.libraries.mediaviewer.impl.gallery.ui.aMediaItemFile
 import io.element.android.libraries.mediaviewer.impl.gallery.ui.aMediaItemImage
 import io.element.android.libraries.mediaviewer.impl.gallery.ui.aMediaItemLoadingIndicator
 import io.element.android.libraries.mediaviewer.test.FakeLocalMediaFactory
+import io.element.android.services.toolbox.test.systemclock.A_FAKE_TIMESTAMP
+import io.element.android.services.toolbox.test.systemclock.FakeSystemClock
 import io.element.android.tests.testutils.lambda.lambdaRecorder
 import io.element.android.tests.testutils.lambda.value
 import io.element.android.tests.testutils.testCoroutineDispatchers
@@ -90,7 +92,12 @@ class MediaViewerDataSourceTest {
             )
             val result = awaitItem()
             assertThat(result).hasSize(1)
-            assertThat(result.first()).isEqualTo(MediaViewerPageData.Loading(Timeline.PaginationDirection.BACKWARDS))
+            assertThat(result.first()).isEqualTo(
+                MediaViewerPageData.Loading(
+                    direction = Timeline.PaginationDirection.BACKWARDS,
+                    timestamp = A_FAKE_TIMESTAMP,
+                )
+            )
         }
     }
 
@@ -118,8 +125,14 @@ class MediaViewerDataSourceTest {
             )
             val result = awaitItem()
             assertThat(result).containsExactly(
-                MediaViewerPageData.Loading(Timeline.PaginationDirection.BACKWARDS),
+                MediaViewerPageData.Loading(
-                MediaViewerPageData.Loading(Timeline.PaginationDirection.FORWARDS),
+                    direction = Timeline.PaginationDirection.BACKWARDS,
+                    timestamp = A_FAKE_TIMESTAMP,
+                ),
+                MediaViewerPageData.Loading(
+                    direction = Timeline.PaginationDirection.FORWARDS,
+                    timestamp = A_FAKE_TIMESTAMP,
+                ),
             )
         }
     }
@@ -255,10 +268,6 @@ class MediaViewerDataSourceTest {
         }
     }
 
-    @Test
-    fun clearLoadingError() {
-    }
-
     private fun TestScope.createMediaViewerDataSource(
         galleryMode: MediaGalleryMode = MediaGalleryMode.Images,
         galleryDataSource: MediaGalleryDataSource = FakeMediaGalleryDataSource(),
@@ -270,5 +279,6 @@ class MediaViewerDataSourceTest {
         galleryDataSource = galleryDataSource,
         mediaLoader = mediaLoader,
         localMediaFactory = localMediaFactory,
+        systemClock = FakeSystemClock(),
     )
 }

libraries/mediaviewer/impl/src/test/kotlin/io/element/android/libraries/mediaviewer/impl/viewer/MediaViewerPresenterTest.kt

@@ -37,6 +37,7 @@ import io.element.android.libraries.mediaviewer.impl.gallery.MediaGalleryMode
 import io.element.android.libraries.mediaviewer.impl.gallery.ui.aMediaItemImage
 import io.element.android.libraries.mediaviewer.test.FakeLocalMediaActions
 import io.element.android.libraries.mediaviewer.test.FakeLocalMediaFactory
+import io.element.android.services.toolbox.test.systemclock.FakeSystemClock
 import io.element.android.tests.testutils.WarmUpRule
 import io.element.android.tests.testutils.lambda.lambdaRecorder
 import io.element.android.tests.testutils.lambda.value
@@ -593,6 +594,7 @@ class MediaViewerPresenterTest {
                 galleryDataSource = mediaGalleryDataSource,
                 mediaLoader = matrixMediaLoader,
                 localMediaFactory = localMediaFactory,
+                systemClock = FakeSystemClock(),
             ),
             room = room,
             localMediaActions = localMediaActions,