Make sure we clean up the pre-processed and uploaded media (#5039)

* Add `MediaSender.cleanUp()` and `MediaPreProcessor.cleanUp()` methods: this will remove the temporary files created when pre-processing media before sending them.

* Make sure we clean up also the previous temporary media.

* Fix the condition for the custom back handler in the attachments preview screen

* Tests: check the clean up is performed when needed

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/attachments/preview/AttachmentsPreviewPresenter.kt

@@ -131,12 +131,17 @@ class AttachmentsPreviewPresenter @AssistedInject constructor(
                                 dismissAfterSend = !useSendQueue,
                                 replyParameters = null,
                             )
+
+                            // Clean up the pre-processed media after it's been sent
+                            mediaSender.cleanUp()
                         }
                     }
                 }
                 AttachmentsPreviewEvents.CancelAndDismiss -> {
                     // Cancel media preprocessing and sending
                     preprocessMediaJob?.cancel()
+                    // If we couldn't send the pre-processed media, remove it
+                    mediaSender.cleanUp()
                     ongoingSendAttachmentJob.value?.cancel()
 
                     // Dismiss the screen

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/attachments/preview/AttachmentsPreviewView.kt

@@ -66,7 +66,7 @@ fun AttachmentsPreviewView(
         state.eventSink(AttachmentsPreviewEvents.CancelAndClearSendState)
     }
 
-    BackHandler(enabled = state.sendActionState !is SendActionState.Sending) {
+    BackHandler(enabled = state.sendActionState !is SendActionState.Sending.Uploading) {
         postCancel()
     }
 

features/messages/impl/src/test/kotlin/io/element/android/features/messages/impl/attachments/AttachmentsPreviewPresenterTest.kt

@@ -123,8 +123,10 @@ class AttachmentsPreviewPresenterTest {
             },
         )
         val onDoneListener = lambdaRecorder<Unit> { }
+        val mediaPreProcessor = FakeMediaPreProcessor()
         val presenter = createAttachmentsPreviewPresenter(
             room = room,
+            mediaPreProcessor = mediaPreProcessor,
             onDoneListener = { onDoneListener() },
         )
         moleculeFlow(RecompositionMode.Immediate) {
@@ -143,6 +145,7 @@ class AttachmentsPreviewPresenterTest {
             assertThat(awaitItem().sendActionState).isEqualTo(SendActionState.Done)
             sendFileResult.assertions().isCalledOnce()
             onDoneListener.assertions().isCalledOnce()
+            assertThat(mediaPreProcessor.cleanUpCallCount).isEqualTo(1)
         }
     }
 
@@ -159,11 +162,10 @@ class AttachmentsPreviewPresenterTest {
         )
         val onDoneListener = lambdaRecorder<Unit> { }
         val processLatch = CompletableDeferred<Unit>()
+        val mediaPreProcessor = FakeMediaPreProcessor(processLatch)
         val presenter = createAttachmentsPreviewPresenter(
             room = room,
-            mediaPreProcessor = FakeMediaPreProcessor(
+            mediaPreProcessor = mediaPreProcessor,
-                processLatch = processLatch,
-            ),
             onDoneListener = { onDoneListener() },
         )
         moleculeFlow(RecompositionMode.Immediate) {
@@ -181,6 +183,7 @@ class AttachmentsPreviewPresenterTest {
             assertThat(awaitItem().sendActionState).isEqualTo(SendActionState.Done)
             sendFileResult.assertions().isCalledOnce()
             onDoneListener.assertions().isCalledOnce()
+            assertThat(mediaPreProcessor.cleanUpCallCount).isEqualTo(1)
         }
     }
 
@@ -197,11 +200,10 @@ class AttachmentsPreviewPresenterTest {
         )
         val onDoneListener = lambdaRecorder<Unit> { }
         val processLatch = CompletableDeferred<Unit>()
+        val mediaPreProcessor = FakeMediaPreProcessor(processLatch)
         val presenter = createAttachmentsPreviewPresenter(
             room = room,
-            mediaPreProcessor = FakeMediaPreProcessor(
+            mediaPreProcessor = mediaPreProcessor,
-                processLatch = processLatch,
-            ),
             onDoneListener = { onDoneListener() },
         )
         moleculeFlow(RecompositionMode.Immediate) {
@@ -219,6 +221,7 @@ class AttachmentsPreviewPresenterTest {
             assertThat(awaitItem().sendActionState).isEqualTo(SendActionState.Done)
             sendFileResult.assertions().isCalledOnce()
             onDoneListener.assertions().isCalledOnce()
+            assertThat(mediaPreProcessor.cleanUpCallCount).isEqualTo(1)
         }
     }
 
@@ -279,7 +282,9 @@ class AttachmentsPreviewPresenterTest {
     fun `present - cancel scenario`() = runTest {
         val onDoneListener = lambdaRecorder<Unit> { }
         val deleteCallback = lambdaRecorder<Uri?, Unit> {}
+        val mediaPreProcessor = FakeMediaPreProcessor()
         val presenter = createAttachmentsPreviewPresenter(
+            mediaPreProcessor = mediaPreProcessor,
             temporaryUriDeleter = FakeTemporaryUriDeleter(deleteCallback),
             onDoneListener = { onDoneListener() },
         )
@@ -293,6 +298,7 @@ class AttachmentsPreviewPresenterTest {
             assertThat(awaitItem().sendActionState).isEqualTo(SendActionState.Done)
             deleteCallback.assertions().isCalledOnce()
             onDoneListener.assertions().isCalledOnce()
+            assertThat(mediaPreProcessor.cleanUpCallCount).isEqualTo(1)
         }
     }
 

libraries/mediaupload/api/src/main/kotlin/io/element/android/libraries/mediaupload/api/MediaPreProcessor.kt

@@ -22,5 +22,10 @@ interface MediaPreProcessor {
         compressIfPossible: Boolean,
     ): Result<MediaUploadInfo>
 
+    /**
+     * Clean up any temporary files or resources used during the media processing.
+     */
+    fun cleanUp()
+
     data class Failure(override val cause: Throwable?) : Exception(cause)
 }

libraries/mediaupload/api/src/main/kotlin/io/element/android/libraries/mediaupload/api/MediaSender.kt

@@ -200,4 +200,9 @@ class MediaSender @Inject constructor(
                 uploadHandler.await()
             }
     }
+
+    /**
+     * Clean up any temporary files or resources used during the media processing.
+     */
+    fun cleanUp() = preProcessor.cleanUp()
 }

libraries/mediaupload/impl/src/main/kotlin/io/element/android/libraries/mediaupload/impl/AndroidMediaPreProcessor.kt

@@ -41,6 +41,7 @@ import kotlinx.coroutines.withContext
 import timber.log.Timber
 import java.io.File
 import java.io.InputStream
+import java.util.UUID
 import javax.inject.Inject
 import kotlin.time.Duration
 import kotlin.time.Duration.Companion.milliseconds
@@ -68,6 +69,9 @@ class AndroidMediaPreProcessor @Inject constructor(
 
     private val contentResolver = context.contentResolver
 
+    private val cacheDir = context.cacheDir
+    private val baseTmpFileDir = File(cacheDir, "uploads")
+
     override suspend fun process(
         uri: Uri,
         mimeType: String,
@@ -100,6 +104,28 @@ class AndroidMediaPreProcessor @Inject constructor(
         }
     }.mapFailure { MediaPreProcessor.Failure(it) }
 
+    override fun cleanUp() {
+        // Clear temporary files created in older versions of the app
+        cacheDir.listFiles()?.onEach { file ->
+            if (file.isFile) {
+                val nameWithoutExtension = file.nameWithoutExtension
+                // UUIDs are 36 characters long, so we check if we can take those 36 characters
+                val nameWithoutExtensionAndRandom = if (nameWithoutExtension.length > 36) {
+                    nameWithoutExtension.substring(0, 36)
+                } else {
+                    // Not a temp file
+                    return@onEach
+                }
+                val isUUID = tryOrNull { UUID.fromString(nameWithoutExtensionAndRandom) } != null
+                if (isUUID && file.extension.isNotEmpty()) {
+                    file.delete()
+                }
+            }
+        }
+        // Clear temporary files created by this pre-processor in the separate uploads directory
+        baseTmpFileDir.listFiles()?.onEach { it.delete() }
+    }
+
     private suspend fun processFile(uri: Uri, mimeType: String): MediaUploadInfo {
         val file = copyToTmpFile(uri)
         val info = FileInfo(
@@ -280,7 +306,10 @@ class AndroidMediaPreProcessor @Inject constructor(
     private suspend fun createTmpFileWithInput(inputStream: InputStream): File? {
         return withContext(coroutineDispatchers.io) {
             tryOrNull {
-                val tmpFile = context.createTmpFile()
+                if (!baseTmpFileDir.exists()) {
+                    baseTmpFileDir.mkdirs()
+                }
+                val tmpFile = context.createTmpFile(baseTmpFileDir)
                 tmpFile.outputStream().use { inputStream.copyTo(it) }
                 tmpFile
             }

libraries/mediaupload/test/src/main/kotlin/io/element/android/libraries/mediaupload/test/FakeMediaPreProcessor.kt

@@ -26,6 +26,9 @@ class FakeMediaPreProcessor(
     var processCallCount = 0
         private set
 
+    var cleanUpCallCount = 0
+        private set
+
     private var result: Result<MediaUploadInfo> = Result.success(
         MediaUploadInfo.AnyFile(
             File("test"),
@@ -108,4 +111,8 @@ class FakeMediaPreProcessor(
             )
         )
     }
+
+    override fun cleanUp() {
+        cleanUpCallCount += 1
+    }
 }