From a915cdacc8b67c25c32a60480e7d2e7f681eeba3 Mon Sep 17 00:00:00 2001
From: Christian Pauly <christian-pauly@posteo.de>
Date: Wed, 30 Mar 2022 09:17:21 +0200
Subject: [PATCH] feat: Display dummy event in timeline for sending files

For thumbnail generation, encrypting
and uploading it is not necessary
to block the UI. The given file
event should already be displayed
in the timeline. This placed it in
the UI and adds a additional
fileSendingStatus property so the
app can fetch the current status.
---
 lib/src/event.dart | 16 +++++++++++
 lib/src/room.dart  | 71 ++++++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 84 insertions(+), 3 deletions(-)

diff --git a/lib/src/event.dart b/lib/src/event.dart
index 11c71319..305b1dd0 100644
--- a/lib/src/event.dart
+++ b/lib/src/event.dart
@@ -19,6 +19,7 @@
 import 'dart:convert';
 import 'dart:typed_data';
 
+import 'package:collection/collection.dart';
 import 'package:html/parser.dart';
 import 'package:http/http.dart' as http;
 
@@ -796,4 +797,19 @@ class Event extends MatrixEvent {
       return _countEmojiRegex.allMatches(plaintextBody).length;
     }
   }
+
+  /// If this event is in Status SENDING and it aims to send a file, then this
+  /// shows the status of the file sending.
+  FileSendingStatus? get fileSendingStatus {
+    final status = unsigned?.tryGet<String>(fileSendingStatusKey);
+    if (status == null) return null;
+    return FileSendingStatus.values.singleWhereOrNull(
+        (fileSendingStatus) => fileSendingStatus.name == status);
+  }
+}
+
+enum FileSendingStatus {
+  generatingThumbnail,
+  encrypting,
+  uploading,
 }
diff --git a/lib/src/room.dart b/lib/src/room.dart
index 3461b5cf..6f22754a 100644
--- a/lib/src/room.dart
+++ b/lib/src/room.dart
@@ -50,6 +50,9 @@ const Map<HistoryVisibility, String> _historyVisibilityMap = {
 const String messageSendingStatusKey =
     'com.famedly.famedlysdk.message_sending_status';
 
+const String fileSendingStatusKey =
+    'com.famedly.famedlysdk.file_sending_status';
+
 const String sortOrderKey = 'com.famedly.famedlysdk.sort_order';
 
 /// Represents a Matrix room.
@@ -687,25 +690,78 @@ class Room {
   ///
   /// In case [file] is a [MatrixImageFile], [thumbnail] is automatically
   /// computed unless it is explicitly provided.
+  /// Set [shrinkImageMaxDimension] to for example `1600` if you want to shrink
+  /// your image before sending. This is ignored if the File is not a
+  /// [MatrixImageFile].
   Future<Uri> sendFileEvent(
     MatrixFile file, {
     String? txid,
     Event? inReplyTo,
     String? editEventId,
     bool waitUntilSent = false,
+    int? shrinkImageMaxDimension,
     MatrixImageFile? thumbnail,
     Map<String, dynamic>? extraContent,
   }) async {
+    txid ??= client.generateUniqueTransactionId();
+
+    // Create a fake Event object as a placeholder for the uploading file:
+    final syncUpdate = SyncUpdate(
+      nextBatch: '',
+      rooms: RoomsUpdate(
+        join: {
+          id: JoinedRoomUpdate(
+            timeline: TimelineUpdate(
+              events: [
+                MatrixEvent(
+                  content: {
+                    'msgtype': file.msgType,
+                    'body': file.name,
+                    'filename': file.name,
+                  },
+                  type: EventTypes.Message,
+                  eventId: txid,
+                  senderId: client.userID!,
+                  originServerTs: DateTime.now(),
+                  unsigned: {
+                    messageSendingStatusKey: EventStatus.sending.intValue,
+                    'transaction_id': txid,
+                  },
+                ),
+              ],
+            ),
+          ),
+        },
+      ),
+    );
+
     MatrixFile uploadFile = file; // ignore: omit_local_variable_types
     // computing the thumbnail in case we can
-    thumbnail ??= (file is MatrixImageFile && encrypted
-        ? await file.generateThumbnail(compute: client.runInBackground)
-        : null);
+    if (file is MatrixImageFile &&
+        (thumbnail == null || shrinkImageMaxDimension != null)) {
+      syncUpdate.rooms!.join!.values.first.timeline!.events!.first
+              .unsigned![fileSendingStatusKey] =
+          FileSendingStatus.generatingThumbnail.name;
+      await _handleFakeSync(syncUpdate);
+      thumbnail ??=
+          await file.generateThumbnail(compute: client.runInBackground);
+      if (shrinkImageMaxDimension != null) {
+        file = await MatrixImageFile.shrink(
+          bytes: file.bytes,
+          name: file.name,
+          maxDimension: shrinkImageMaxDimension,
+        );
+      }
+    }
+
     MatrixFile? uploadThumbnail =
         thumbnail; // ignore: omit_local_variable_types
     EncryptedFile? encryptedFile;
     EncryptedFile? encryptedThumbnail;
     if (encrypted && client.fileEncryptionEnabled) {
+      syncUpdate.rooms!.join!.values.first.timeline!.events!.first
+          .unsigned![fileSendingStatusKey] = FileSendingStatus.encrypting.name;
+      await _handleFakeSync(syncUpdate);
       encryptedFile = await file.encrypt();
       uploadFile = encryptedFile.toMatrixFile();
 
@@ -717,6 +773,9 @@ class Room {
     Uri? uploadResp, thumbnailUploadResp;
 
     final timeoutDate = DateTime.now().add(client.sendTimelineEventTimeout);
+
+    syncUpdate.rooms!.join!.values.first.timeline!.events!.first
+        .unsigned![fileSendingStatusKey] = FileSendingStatus.uploading.name;
     while (uploadResp == null ||
         (uploadThumbnail != null && thumbnailUploadResp == null)) {
       try {
@@ -733,9 +792,15 @@ class Room {
               )
             : null;
       } on MatrixException catch (_) {
+        syncUpdate.rooms!.join!.values.first.timeline!.events!.first
+            .unsigned![messageSendingStatusKey] = EventStatus.error.intValue;
+        await _handleFakeSync(syncUpdate);
         rethrow;
       } catch (_) {
         if (DateTime.now().isAfter(timeoutDate)) {
+          syncUpdate.rooms!.join!.values.first.timeline!.events!.first
+              .unsigned![messageSendingStatusKey] = EventStatus.error.intValue;
+          await _handleFakeSync(syncUpdate);
           rethrow;
         }
         Logs().v('Send File into room failed. Try again...');