Add tests on FocusedMediaTimeline

libraries/mediaviewer/impl/src/test/kotlin/io/element/android/libraries/mediaviewer/impl/gallery/FocusedMediaTimelineTest.kt

@@ -0,0 +1,100 @@
+/*
+ * Copyright 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.mediaviewer.impl.gallery
+
+import com.google.common.truth.Truth.assertThat
+import io.element.android.libraries.matrix.api.core.EventId
+import io.element.android.libraries.matrix.api.room.MatrixRoom
+import io.element.android.libraries.matrix.api.timeline.Timeline
+import io.element.android.libraries.matrix.test.AN_EVENT_ID
+import io.element.android.libraries.matrix.test.room.FakeMatrixRoom
+import io.element.android.libraries.matrix.test.timeline.FakeTimeline
+import io.element.android.libraries.mediaviewer.impl.gallery.ui.aMediaItemImage
+import io.element.android.tests.testutils.lambda.lambdaRecorder
+import io.element.android.tests.testutils.lambda.value
+import kotlinx.collections.immutable.persistentListOf
+import kotlinx.coroutines.test.runTest
+import org.junit.Test
+
+class FocusedMediaTimelineTest {
+    @Test
+    fun `check the returned cache data`() {
+        val media = aMediaItemImage()
+        val sut = createFocusedMediaTimeline(
+            initialMediaItem = media,
+        )
+        val cache = sut.cache
+        assertThat(cache.imageAndVideoItems.size).isEqualTo(3)
+        assertThat(cache.fileItems.size).isEqualTo(3)
+        assertThat(cache.imageAndVideoItems[1]).isEqualTo(media)
+        assertThat(cache.fileItems[1]).isEqualTo(media)
+    }
+
+    @Test
+    fun `when event is not found, the cache is returned`() {
+        val media = aMediaItemImage(
+            eventId = AN_EVENT_ID,
+        )
+        val sut = createFocusedMediaTimeline(
+            initialMediaItem = media,
+        )
+        val cache = sut.orCache(
+            GroupedMediaItems(
+                imageAndVideoItems = persistentListOf(),
+                fileItems = persistentListOf(),
+            )
+        )
+        assertThat(cache.imageAndVideoItems.size).isEqualTo(3)
+        assertThat(cache.fileItems.size).isEqualTo(3)
+    }
+
+    @Test
+    fun `when event is found, the data is returned`() {
+        val media = aMediaItemImage(
+            eventId = AN_EVENT_ID,
+        )
+        val sut = createFocusedMediaTimeline(
+            initialMediaItem = media,
+        )
+        val cache = sut.orCache(
+            GroupedMediaItems(
+                imageAndVideoItems = persistentListOf(media),
+                fileItems = persistentListOf(),
+            )
+        )
+        assertThat(cache.imageAndVideoItems.size).isEqualTo(1)
+        assertThat(cache.fileItems).isEmpty()
+    }
+
+    @Test
+    fun `getTimeline returns the timeline provided by the room`() = runTest {
+        val mediaTimelineResult = lambdaRecorder<EventId?, Result<Timeline>> {
+            Result.success(FakeTimeline())
+        }
+        val room = FakeMatrixRoom(
+            mediaTimelineResult = mediaTimelineResult,
+        )
+        val sut = createFocusedMediaTimeline(
+            room = room,
+            eventId = AN_EVENT_ID,
+        )
+        val timeline = sut.getTimeline()
+        assertThat(timeline.isSuccess).isTrue()
+        mediaTimelineResult.assertions().isCalledOnce().with(value(AN_EVENT_ID))
+    }
+
+    private fun createFocusedMediaTimeline(
+        room: MatrixRoom = FakeMatrixRoom(),
+        eventId: EventId = AN_EVENT_ID,
+        initialMediaItem: MediaItem.Event = aMediaItemImage(),
+    ) = FocusedMediaTimeline(
+        room = room,
+        eventId = eventId,
+        initialMediaItem = initialMediaItem,
+    )
+}