Preload full set of preview image metadata pages

This is the first step in mitigating the bottleneck of slow metadata
loading by proactively loading pages to the max window size.

Test: atest CursorPreviewsInteractorTest FetchPreviewsInteractorTest
Test: manual test using ShareTest with high metadata latency
BUG: 341923886
Flag: android.service.chooser.chooser_payload_toggling
Change-Id: I1192e7bdf7db77573990745dd5b05d7ef86d7f20

3 files changed, 61 insertions, 157 deletions

diff --git a/java/src/com/android/intentresolver/contentpreview/payloadtoggle/domain/interactor/CursorPreviewsInteractor.kt b/java/src/com/android/intentresolver/contentpreview/payloadtoggle/domain/interactor/CursorPreviewsInteractor.kt
index 97b087e1..f02834e0 100644
--- a/java/src/com/android/intentresolver/contentpreview/payloadtoggle/domain/interactor/CursorPreviewsInteractor.kt
+++ b/java/src/com/android/intentresolver/contentpreview/payloadtoggle/domain/interactor/CursorPreviewsInteractor.kt
@@ -76,10 +76,42 @@ constructor(
                 .toMap(ConcurrentHashMap())
         val pagedCursor: PagedCursor<CursorRow?> = uriCursor.paged(pageSize)
         val startPosition = uriCursor.extras?.getInt(POSITION, 0) ?: 0
-        val state = readInitialState(pagedCursor, startPosition, unclaimedRecords)
+        val state =
+            loadToMaxPages(
+                initialState = readInitialState(pagedCursor, startPosition, unclaimedRecords),
+                pagedCursor = pagedCursor,
+                unclaimedRecords = unclaimedRecords,
+            )
         processLoadRequests(state, pagedCursor, unclaimedRecords)
     }
 
+    private suspend fun loadToMaxPages(
+        initialState: CursorWindow,
+        pagedCursor: PagedCursor<CursorRow?>,
+        unclaimedRecords: MutableUnclaimedMap,
+    ): CursorWindow {
+        var state = initialState
+        val startPageNum = state.firstLoadedPageNum
+        while ((state.hasMoreLeft || state.hasMoreRight) && state.numLoadedPages < maxLoadedPages) {
+            interactor.setPreviews(
+                previewsByKey = state.merged.values.toSet(),
+                startIndex = startPageNum,
+                hasMoreLeft = state.hasMoreLeft,
+                hasMoreRight = state.hasMoreRight,
+            )
+            val loadedLeft = startPageNum - state.firstLoadedPageNum
+            val loadedRight = state.lastLoadedPageNum - startPageNum
+            state =
+                when {
+                    state.hasMoreLeft && loadedLeft < loadedRight ->
+                        state.loadMoreLeft(pagedCursor, unclaimedRecords)
+                    state.hasMoreRight -> state.loadMoreRight(pagedCursor, unclaimedRecords)
+                    else -> state.loadMoreLeft(pagedCursor, unclaimedRecords)
+                }
+        }
+        return state
+    }
+
     /** Loop forever, processing any loading requests from the UI and updating local cache. */
     private suspend fun processLoadRequests(
         initialState: CursorWindow,
@@ -301,5 +333,5 @@ annotation class MaxLoadedPages
 object ShareouselConstants {
     @Provides @PageSize fun pageSize(): Int = 16
 
-    @Provides @MaxLoadedPages fun maxLoadedPages(): Int = 3
+    @Provides @MaxLoadedPages fun maxLoadedPages(): Int = 8
 }
diff --git a/tests/unit/src/com/android/intentresolver/contentpreview/payloadtoggle/domain/interactor/CursorPreviewsInteractorTest.kt b/tests/unit/src/com/android/intentresolver/contentpreview/payloadtoggle/domain/interactor/CursorPreviewsInteractorTest.kt
index ff699373..45e456e0 100644
--- a/tests/unit/src/com/android/intentresolver/contentpreview/payloadtoggle/domain/interactor/CursorPreviewsInteractorTest.kt
+++ b/tests/unit/src/com/android/intentresolver/contentpreview/payloadtoggle/domain/interactor/CursorPreviewsInteractorTest.kt
@@ -111,8 +111,12 @@ class CursorPreviewsInteractorTest {
     @Test
     fun initialCursorLoad() =
         runTestWithDeps(
+            cursor = (0 until 10),
+            cursorStartPosition = 2,
             cursorSizes = mapOf(0 to (200 x 100)),
-            metadatSizes = mapOf(0 to (300 x 100), 3 to (400 x 100))
+            metadatSizes = mapOf(0 to (300 x 100), 3 to (400 x 100)),
+            pageSize = 2,
+            maxLoadedPages = 3,
         ) { deps ->
             backgroundScope.launch {
                 cursorPreviewsInteractor.launch(deps.cursor, deps.initialPreviews)
@@ -120,31 +124,27 @@ class CursorPreviewsInteractorTest {
             runCurrent()
 
             assertThat(cursorPreviewsRepository.previewsModel.value).isNotNull()
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.startIdx).isEqualTo(0)
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.loadMoreLeft).isNull()
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.loadMoreRight).isNull()
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels)
-                .containsExactly(
-                    PreviewModel(
-                        uri = Uri.fromParts("scheme0", "ssp0", "fragment0"),
-                        mimeType = "image/bitmap",
-                        aspectRatio = 2f,
-                    ),
-                    PreviewModel(
-                        uri = Uri.fromParts("scheme1", "ssp1", "fragment1"),
-                        mimeType = "image/bitmap"
-                    ),
-                    PreviewModel(
-                        uri = Uri.fromParts("scheme2", "ssp2", "fragment2"),
-                        mimeType = "image/bitmap"
-                    ),
-                    PreviewModel(
-                        uri = Uri.fromParts("scheme3", "ssp3", "fragment3"),
-                        mimeType = "image/bitmap",
-                        aspectRatio = 4f,
-                    ),
-                )
-                .inOrder()
+            with(cursorPreviewsRepository.previewsModel.value!!) {
+                assertThat(previewModels)
+                    .containsExactlyElementsIn(
+                        List(6) {
+                            PreviewModel(
+                                uri = Uri.fromParts("scheme$it", "ssp$it", "fragment$it"),
+                                mimeType = "image/bitmap",
+                                aspectRatio =
+                                    when (it) {
+                                        0 -> 2f
+                                        3 -> 4f
+                                        else -> 1f
+                                    }
+                            )
+                        }
+                    )
+                    .inOrder()
+                assertThat(startIdx).isEqualTo(0)
+                assertThat(loadMoreLeft).isNull()
+                assertThat(loadMoreRight).isNotNull()
+            }
         }
 
     @Test
@@ -181,39 +181,6 @@ class CursorPreviewsInteractorTest {
         }
 
     @Test
-    fun loadMoreLeft_keepRight() =
-        runTestWithDeps(
-            initialSelection = listOf(24),
-            cursor = (0 until 48),
-            pageSize = 16,
-            maxLoadedPages = 2,
-        ) { deps ->
-            backgroundScope.launch {
-                cursorPreviewsInteractor.launch(deps.cursor, deps.initialPreviews)
-            }
-            runCurrent()
-
-            assertThat(cursorPreviewsRepository.previewsModel.value).isNotNull()
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels).hasSize(16)
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels.first().uri)
-                .isEqualTo(Uri.fromParts("scheme16", "ssp16", "fragment16"))
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels.last().uri)
-                .isEqualTo(Uri.fromParts("scheme31", "ssp31", "fragment31"))
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.loadMoreLeft).isNotNull()
-
-            cursorPreviewsRepository.previewsModel.value!!.loadMoreLeft!!.invoke()
-            runCurrent()
-
-            assertThat(cursorPreviewsRepository.previewsModel.value).isNotNull()
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels).hasSize(32)
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels.first().uri)
-                .isEqualTo(Uri.fromParts("scheme0", "ssp0", "fragment0"))
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels.last().uri)
-                .isEqualTo(Uri.fromParts("scheme31", "ssp31", "fragment31"))
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.loadMoreLeft).isNull()
-        }
-
-    @Test
     fun loadMoreRight_evictLeft() =
         runTestWithDeps(
             initialSelection = listOf(24),
@@ -246,38 +213,6 @@ class CursorPreviewsInteractorTest {
         }
 
     @Test
-    fun loadMoreRight_keepLeft() =
-        runTestWithDeps(
-            initialSelection = listOf(24),
-            cursor = (0 until 48),
-            pageSize = 16,
-            maxLoadedPages = 2,
-        ) { deps ->
-            backgroundScope.launch {
-                cursorPreviewsInteractor.launch(deps.cursor, deps.initialPreviews)
-            }
-            runCurrent()
-
-            assertThat(cursorPreviewsRepository.previewsModel.value).isNotNull()
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels).hasSize(16)
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels.first().uri)
-                .isEqualTo(Uri.fromParts("scheme16", "ssp16", "fragment16"))
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels.last().uri)
-                .isEqualTo(Uri.fromParts("scheme31", "ssp31", "fragment31"))
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.loadMoreRight).isNotNull()
-
-            cursorPreviewsRepository.previewsModel.value!!.loadMoreRight!!.invoke()
-            runCurrent()
-
-            assertThat(cursorPreviewsRepository.previewsModel.value).isNotNull()
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels).hasSize(32)
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels.first().uri)
-                .isEqualTo(Uri.fromParts("scheme16", "ssp16", "fragment16"))
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels.last().uri)
-                .isEqualTo(Uri.fromParts("scheme47", "ssp47", "fragment47"))
-        }
-
-    @Test
     fun noMoreRight_appendUnclaimedFromInitialSelection() =
         runTestWithDeps(
             initialSelection = listOf(24, 50),
diff --git a/tests/unit/src/com/android/intentresolver/contentpreview/payloadtoggle/domain/interactor/FetchPreviewsInteractorTest.kt b/tests/unit/src/com/android/intentresolver/contentpreview/payloadtoggle/domain/interactor/FetchPreviewsInteractorTest.kt
index 735bcb1d..146892d0 100644
--- a/tests/unit/src/com/android/intentresolver/contentpreview/payloadtoggle/domain/interactor/FetchPreviewsInteractorTest.kt
+++ b/tests/unit/src/com/android/intentresolver/contentpreview/payloadtoggle/domain/interactor/FetchPreviewsInteractorTest.kt
@@ -53,7 +53,7 @@ class FetchPreviewsInteractorTest {
         cursor: Iterable<Int> = (0 until 4),
         cursorStartPosition: Int = cursor.count() / 2,
         pageSize: Int = 16,
-        maxLoadedPages: Int = 3,
+        maxLoadedPages: Int = 8,
         previewSizes: Map<Int, Size> = emptyMap(),
         block: KosmosTestScope.() -> Unit,
     ) {
@@ -202,38 +202,6 @@ class FetchPreviewsInteractorTest {
         }
 
     @Test
-    fun loadMoreLeft_keepRight() =
-        runTest(
-            initialSelection = listOf(24),
-            cursor = (0 until 48),
-            pageSize = 16,
-            maxLoadedPages = 2,
-        ) {
-            backgroundScope.launch { fetchPreviewsInteractor.activate() }
-            fakeCursorResolver.complete()
-            runCurrent()
-
-            assertThat(cursorPreviewsRepository.previewsModel.value).isNotNull()
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels).hasSize(16)
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels.first().uri)
-                .isEqualTo(Uri.fromParts("scheme16", "ssp16", "fragment16"))
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels.last().uri)
-                .isEqualTo(Uri.fromParts("scheme31", "ssp31", "fragment31"))
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.loadMoreLeft).isNotNull()
-
-            cursorPreviewsRepository.previewsModel.value!!.loadMoreLeft!!.invoke()
-            runCurrent()
-
-            assertThat(cursorPreviewsRepository.previewsModel.value).isNotNull()
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels).hasSize(32)
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels.first().uri)
-                .isEqualTo(Uri.fromParts("scheme0", "ssp0", "fragment0"))
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels.last().uri)
-                .isEqualTo(Uri.fromParts("scheme31", "ssp31", "fragment31"))
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.loadMoreLeft).isNull()
-        }
-
-    @Test
     fun loadMoreRight_evictLeft() =
         runTest(
             initialSelection = listOf(24),
@@ -265,37 +233,6 @@ class FetchPreviewsInteractorTest {
         }
 
     @Test
-    fun loadMoreRight_keepLeft() =
-        runTest(
-            initialSelection = listOf(24),
-            cursor = (0 until 48),
-            pageSize = 16,
-            maxLoadedPages = 2,
-        ) {
-            backgroundScope.launch { fetchPreviewsInteractor.activate() }
-            fakeCursorResolver.complete()
-            runCurrent()
-
-            assertThat(cursorPreviewsRepository.previewsModel.value).isNotNull()
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels).hasSize(16)
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels.first().uri)
-                .isEqualTo(Uri.fromParts("scheme16", "ssp16", "fragment16"))
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels.last().uri)
-                .isEqualTo(Uri.fromParts("scheme31", "ssp31", "fragment31"))
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.loadMoreRight).isNotNull()
-
-            cursorPreviewsRepository.previewsModel.value!!.loadMoreRight!!.invoke()
-            runCurrent()
-
-            assertThat(cursorPreviewsRepository.previewsModel.value).isNotNull()
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels).hasSize(32)
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels.first().uri)
-                .isEqualTo(Uri.fromParts("scheme16", "ssp16", "fragment16"))
-            assertThat(cursorPreviewsRepository.previewsModel.value!!.previewModels.last().uri)
-                .isEqualTo(Uri.fromParts("scheme47", "ssp47", "fragment47"))
-        }
-
-    @Test
     fun noMoreRight_appendUnclaimedFromInitialSelection() =
         runTest(
             initialSelection = listOf(24, 50),