Remove bitmap caching from ScrollableImagePreview

Remove bitmap caching from ScrollableImagePreview; instead, extend the
image loader interface to proivde a cache-control option.
ScrollableImagePreview$BatchPreviewLoader requests caching only for the
first visible items as we'd like them to be displayed as fast as
possible and not be evicted by any of the remaining items.
Minor fixes inside ImagePreviewImageLoader.
ImageLoader is moved into contentpreview package.

Bug: 271613784
Test: unit tests
Test: Manual testing with injected extensive logging.
Change-Id: Ic07572e1fb73d589d98207af8fe58ae52698802a

6 files changed, 96 insertions, 7 deletions

diff --git a/java/tests/src/com/android/intentresolver/ChooserActivityOverrideData.java b/java/tests/src/com/android/intentresolver/ChooserActivityOverrideData.java
index 2a4d654a..9ebeb79d 100644
--- a/java/tests/src/com/android/intentresolver/ChooserActivityOverrideData.java
+++ b/java/tests/src/com/android/intentresolver/ChooserActivityOverrideData.java
@@ -28,6 +28,7 @@ import android.os.UserHandle;
 
 import com.android.intentresolver.AbstractMultiProfilePagerAdapter.CrossProfileIntentsChecker;
 import com.android.intentresolver.chooser.TargetInfo;
+import com.android.intentresolver.contentpreview.ImageLoader;
 import com.android.intentresolver.flags.FeatureFlagRepository;
 import com.android.intentresolver.shortcuts.ShortcutLoader;
 
diff --git a/java/tests/src/com/android/intentresolver/ChooserWrapperActivity.java b/java/tests/src/com/android/intentresolver/ChooserWrapperActivity.java
index dc9baade..d23e4a66 100644
--- a/java/tests/src/com/android/intentresolver/ChooserWrapperActivity.java
+++ b/java/tests/src/com/android/intentresolver/ChooserWrapperActivity.java
@@ -35,6 +35,7 @@ import android.os.UserHandle;
 import com.android.intentresolver.AbstractMultiProfilePagerAdapter.CrossProfileIntentsChecker;
 import com.android.intentresolver.chooser.DisplayResolveInfo;
 import com.android.intentresolver.chooser.TargetInfo;
+import com.android.intentresolver.contentpreview.ImageLoader;
 import com.android.intentresolver.flags.FeatureFlagRepository;
 import com.android.intentresolver.grid.ChooserGridAdapter;
 import com.android.intentresolver.shortcuts.ShortcutLoader;
diff --git a/java/tests/src/com/android/intentresolver/ImagePreviewImageLoaderTest.kt b/java/tests/src/com/android/intentresolver/ImagePreviewImageLoaderTest.kt
index f327e19e..3c399cc4 100644
--- a/java/tests/src/com/android/intentresolver/ImagePreviewImageLoaderTest.kt
+++ b/java/tests/src/com/android/intentresolver/ImagePreviewImageLoaderTest.kt
@@ -19,11 +19,18 @@ package com.android.intentresolver
 import android.content.ContentResolver
 import android.content.Context
 import android.content.res.Resources
+import android.graphics.Bitmap
 import android.net.Uri
 import android.util.Size
 import androidx.lifecycle.Lifecycle
+import kotlinx.coroutines.CancellationException
+import kotlinx.coroutines.CoroutineStart.UNDISPATCHED
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.async
+import kotlinx.coroutines.coroutineScope
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.test.StandardTestDispatcher
 import kotlinx.coroutines.test.TestCoroutineScheduler
 import kotlinx.coroutines.test.UnconfinedTestDispatcher
 import kotlinx.coroutines.test.resetMain
@@ -41,7 +48,10 @@ class ImagePreviewImageLoaderTest {
     private val imageSize = Size(300, 300)
     private val uriOne = Uri.parse("content://org.package.app/image-1.png")
     private val uriTwo = Uri.parse("content://org.package.app/image-2.png")
-    private val contentResolver = mock<ContentResolver>()
+    private val bitmap = Bitmap.createBitmap(1, 1, Bitmap.Config.ARGB_8888)
+    private val contentResolver = mock<ContentResolver> {
+        whenever(loadThumbnail(any(), any(), anyOrNull())).thenReturn(bitmap)
+    }
     private val resources = mock<Resources> {
         whenever(getDimensionPixelSize(R.dimen.chooser_preview_image_max_dimen))
             .thenReturn(imageSize.width)
@@ -70,7 +80,7 @@ class ImagePreviewImageLoaderTest {
     }
 
     @Test
-    fun test_prePopulate() = runTest {
+    fun prePopulate_cachesImagesUpToTheCacheSize() = runTest {
         testSubject.prePopulate(listOf(uriOne, uriTwo))
 
         verify(contentResolver, times(1)).loadThumbnail(uriOne, imageSize, null)
@@ -81,7 +91,7 @@ class ImagePreviewImageLoaderTest {
     }
 
     @Test
-    fun test_invoke_return_cached_image() = runTest {
+    fun invoke_returnCachedImageWhenCalledTwice() = runTest {
         testSubject(uriOne)
         testSubject(uriOne)
 
@@ -89,7 +99,33 @@ class ImagePreviewImageLoaderTest {
     }
 
     @Test
-    fun test_invoke_old_records_evicted_from_the_cache() = runTest {
+    fun invoke_whenInstructed_doesNotCache() = runTest {
+        testSubject(uriOne, false)
+        testSubject(uriOne, false)
+
+        verify(contentResolver, times(2)).loadThumbnail(any(), any(), anyOrNull())
+    }
+
+    @Test
+    fun invoke_overlappedRequests_Deduplicate() = runTest {
+        val scheduler = TestCoroutineScheduler()
+        val dispatcher = StandardTestDispatcher(scheduler)
+        val testSubject = ImagePreviewImageLoader(context, lifecycleOwner.lifecycle, 1, dispatcher)
+        coroutineScope {
+            launch(start = UNDISPATCHED) {
+                testSubject(uriOne, false)
+            }
+            launch(start = UNDISPATCHED) {
+                testSubject(uriOne, false)
+            }
+            scheduler.advanceUntilIdle()
+        }
+
+        verify(contentResolver, times(1)).loadThumbnail(any(), any(), anyOrNull())
+    }
+
+    @Test
+    fun invoke_oldRecordsEvictedFromTheCache() = runTest {
         testSubject(uriOne)
         testSubject(uriTwo)
         testSubject(uriTwo)
@@ -98,4 +134,53 @@ class ImagePreviewImageLoaderTest {
         verify(contentResolver, times(2)).loadThumbnail(uriOne, imageSize, null)
         verify(contentResolver, times(1)).loadThumbnail(uriTwo, imageSize, null)
     }
+
+    @Test
+    fun invoke_doNotCacheNulls() = runTest {
+        whenever(contentResolver.loadThumbnail(any(), any(), anyOrNull())).thenReturn(null)
+        testSubject(uriOne)
+        testSubject(uriOne)
+
+        verify(contentResolver, times(2)).loadThumbnail(uriOne, imageSize, null)
+    }
+
+    @Test(expected = CancellationException::class)
+    fun invoke_onClosedImageLoaderScope_throwsCancellationException() = runTest {
+        lifecycleOwner.state = Lifecycle.State.DESTROYED
+        testSubject(uriOne)
+    }
+
+    @Test(expected = CancellationException::class)
+    fun invoke_imageLoaderScopeClosedMidflight_throwsCancellationException() = runTest {
+        val scheduler = TestCoroutineScheduler()
+        val dispatcher = StandardTestDispatcher(scheduler)
+        val testSubject = ImagePreviewImageLoader(context, lifecycleOwner.lifecycle, 1, dispatcher)
+        coroutineScope {
+            val deferred = async(start = UNDISPATCHED) {
+                testSubject(uriOne, false)
+            }
+            lifecycleOwner.state = Lifecycle.State.DESTROYED
+            scheduler.advanceUntilIdle()
+            deferred.await()
+        }
+    }
+
+    @Test
+    fun invoke_multipleCallsWithDifferentCacheInstructions_cachingPrevails() = runTest {
+        val scheduler = TestCoroutineScheduler()
+        val dispatcher = StandardTestDispatcher(scheduler)
+        val testSubject = ImagePreviewImageLoader(context, lifecycleOwner.lifecycle, 1, dispatcher)
+        coroutineScope {
+            launch(start = UNDISPATCHED) {
+                testSubject(uriOne, false)
+            }
+            launch(start = UNDISPATCHED) {
+                testSubject(uriOne, true)
+            }
+            scheduler.advanceUntilIdle()
+        }
+        testSubject(uriOne, true)
+
+        verify(contentResolver, times(1)).loadThumbnail(uriOne, imageSize, null)
+    }
 }
diff --git a/java/tests/src/com/android/intentresolver/TestPreviewImageLoader.kt b/java/tests/src/com/android/intentresolver/TestPreviewImageLoader.kt
index 2f240d58..74a253b8 100644
--- a/java/tests/src/com/android/intentresolver/TestPreviewImageLoader.kt
+++ b/java/tests/src/com/android/intentresolver/TestPreviewImageLoader.kt
@@ -18,6 +18,7 @@ package com.android.intentresolver
 
 import android.graphics.Bitmap
 import android.net.Uri
+import com.android.intentresolver.contentpreview.ImageLoader
 import java.util.function.Consumer
 
 internal class TestPreviewImageLoader(
@@ -27,6 +28,7 @@ internal class TestPreviewImageLoader(
         callback.accept(bitmaps[uri])
     }
 
-    override suspend fun invoke(uri: Uri): Bitmap? = bitmaps[uri]
+    override suspend fun invoke(uri: Uri, caching: Boolean): Bitmap? = bitmaps[uri]
+
     override fun prePopulate(uris: List<Uri>) = Unit
 }
diff --git a/java/tests/src/com/android/intentresolver/UnbundledChooserActivityTest.java b/java/tests/src/com/android/intentresolver/UnbundledChooserActivityTest.java
index 0a60b8c7..de5498db 100644
--- a/java/tests/src/com/android/intentresolver/UnbundledChooserActivityTest.java
+++ b/java/tests/src/com/android/intentresolver/UnbundledChooserActivityTest.java
@@ -104,6 +104,7 @@ import androidx.test.platform.app.InstrumentationRegistry;
 import androidx.test.rule.ActivityTestRule;
 
 import com.android.intentresolver.chooser.DisplayResolveInfo;
+import com.android.intentresolver.contentpreview.ImageLoader;
 import com.android.intentresolver.shortcuts.ShortcutLoader;
 import com.android.internal.config.sysui.SystemUiDeviceConfigFlags;
 import com.android.internal.logging.nano.MetricsProto.MetricsEvent;
diff --git a/java/tests/src/com/android/intentresolver/contentpreview/ChooserContentPreviewUiTest.kt b/java/tests/src/com/android/intentresolver/contentpreview/ChooserContentPreviewUiTest.kt
index 7b9a0ce6..8eec289e 100644
--- a/java/tests/src/com/android/intentresolver/contentpreview/ChooserContentPreviewUiTest.kt
+++ b/java/tests/src/com/android/intentresolver/contentpreview/ChooserContentPreviewUiTest.kt
@@ -21,7 +21,6 @@ import android.content.ContentInterface
 import android.content.Intent
 import android.graphics.Bitmap
 import android.net.Uri
-import com.android.intentresolver.ImageLoader
 import com.android.intentresolver.any
 import com.android.intentresolver.anyOrNull
 import com.android.intentresolver.contentpreview.ChooserContentPreviewUi.ActionFactory
@@ -48,7 +47,7 @@ class ChooserContentPreviewUiTest {
             callback.accept(null)
         }
         override fun prePopulate(uris: List<Uri>) = Unit
-        override suspend fun invoke(uri: Uri): Bitmap? = null
+        override suspend fun invoke(uri: Uri, caching: Boolean): Bitmap? = null
     }
     private val actionFactory = object : ActionFactory {
         override fun createCopyButton() = ActionRow.Action(label = "Copy", icon = null) {}