Rejoin room when websocket connection was lost.

Signed-off-by: Ivan Sein <ivan@nextcloud.com>

VideoCalls/NCExternalSignalingController.m

@@ -10,6 +10,7 @@
 
 #import "SRWebSocket.h"
 #import "NCAPIController.h"
+#import "NCRoomsManager.h"
 #import "NCSettingsController.h"
 
 static NSTimeInterval kInitialReconnectInterval = 1;
@@ -215,6 +216,11 @@ NSString * const NCESReceivedParticipantListMessageNotification = @"NCESReceived
         [self sendMessage:message];
     }
     _pendingMessages = [NSMutableArray new];
+    
+    // Re-join if user was in a room
+    if (_currentRoom && _sessionId) {
+        [[NCRoomsManager sharedInstance] rejoinRoom:_currentRoom];
+    }
 }
 
 - (void)errorResponseReceived:(NSDictionary *)errorDict
@@ -242,6 +248,7 @@ NSString * const NCESReceivedParticipantListMessageNotification = @"NCESReceived
 - (void)leaveRoom:(NSString *)roomId
 {
     if ([_currentRoom isEqualToString:roomId]) {
+        _currentRoom = nil;
         [self joinRoom:@"" withSessionId:@""];
     }
 }

VideoCalls/NCRoomsManager.h

@@ -27,6 +27,7 @@ extern NSString * const NCRoomsManagerDidStartCallNotification;
 // Room
 - (void)updateRooms;
 - (void)updateRoom:(NSString *)token;
+- (void)rejoinRoom:(NSString *)token;
 // Chat
 - (void)startChatInRoom:(NCRoom *)room;
 - (void)sendChatMessage:(NSString *)message toRoom:(NCRoom *)room;

VideoCalls/NCRoomsManager.m

@@ -109,6 +109,26 @@ NSString * const NCRoomsManagerDidReceiveChatMessagesNotification   = @"ChatMess
     }
 }
 
+- (void)rejoinRoom:(NSString *)token
+{
+    NCRoomController *roomController = [_activeRooms objectForKey:token];
+    if (roomController) {
+        _joiningRoom = [token copy];
+        _joinRoomTask = [[NCAPIController sharedInstance] joinRoom:token withCompletionBlock:^(NSString *sessionId, NSError *error) {
+            if (!error) {
+                roomController.userSessionId = sessionId;
+                roomController.inChat = YES;
+                if ([[NCExternalSignalingController sharedInstance] isEnabled]) {
+                    [[NCExternalSignalingController sharedInstance] joinRoom:token withSessionId:sessionId];
+                }
+            } else {
+                NSLog(@"Could not re-join room. Error: %@", error.description);
+            }
+            _joiningRoom = nil;
+        }];
+    }
+}
+
 - (void)leaveRoom:(NSString *)token
 {
     // Check if leaving the room we are joining