fix(app/download_processor): detect deleted files

app/src/main/kotlin/me/rhunk/snapenhance/download/DownloadProcessor.kt

@@ -341,6 +341,16 @@ class DownloadProcessor (
 
                 if (task.status.isFinalStage()) {
                     if (task.status != TaskStatus.SUCCESS) return@let
+                    // check if the media file has been deleted
+                    if (task.type == TaskType.DOWNLOAD) {
+                        val outputFile = runCatching {
+                            DocumentFile.fromTreeUri(remoteSideContext.androidContext, Uri.parse(task.extra))
+                        }.getOrNull()
+
+                        if (outputFile != null && !outputFile.exists()) {
+                            return@let
+                        }
+                    }
                     callbackOnFailure(translation["already_downloaded_toast"], null)
                 } else {
                     callbackOnFailure(translation["already_queued_toast"], null)

app/src/main/kotlin/me/rhunk/snapenhance/task/TaskManager.kt

@@ -50,6 +50,13 @@ class TaskManager(
         return runBlocking {
             suspendCoroutine {
                 queueExecutor.execute {
+                    taskDatabase.rawQuery("SELECT * FROM tasks WHERE hash = ?", arrayOf(task.hash)).use { cursor ->
+                        if (cursor.moveToNext()) {
+                            it.resumeWith(Result.success(cursor.getLong("id")))
+                            return@execute
+                        }
+                    }
+
                     val result = taskDatabase.insert("tasks", null, ContentValues().apply {
                         put("type", task.type.key)
                         put("hash", task.hash)
@@ -57,6 +64,7 @@ class TaskManager(
                         put("status", task.status.key)
                         put("extra", task.extra)
                     })
+
                     it.resumeWith(Result.success(result))
                 }
             }