Add background refresh to update conversation-list

Signed-off-by: Marcel Müller <marcel-mueller@gmx.de>

NextcloudTalk/AppDelegate.m

@@ -32,6 +32,10 @@
 
 #import <UserNotifications/UserNotifications.h>
 
+#import <BackgroundTasks/BGTaskScheduler.h>
+#import <BackgroundTasks/BGTaskRequest.h>
+#import <BackgroundTasks/BGTask.h>
+
 #import "NCAudioController.h"
 #import "NCAppBranding.h"
 #import "NCConnectionController.h"
@@ -82,6 +86,8 @@
         [[BKPasscodeLockScreenManager sharedManager] showLockScreen:NO];
     });
     
+    [self registerBackgroundFetchTask];
+    
     return YES;
 }
 
@@ -112,6 +118,10 @@
     // If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
     // show passcode view controller when enter background. Screen will be obscured from here.
     [[BKPasscodeLockScreenManager sharedManager] showLockScreen:NO];
+    
+    if (@available(iOS 13.0, *)) {
+        [self scheduleAppRefresh];
+    }
 }
 
 
@@ -308,4 +318,66 @@
     return navigationController;
 }
 
+#pragma mark - BackgroundFetch / AppRefresh
+
+- (void)registerBackgroundFetchTask {
+    NSString *refreshTaskIdentifier = [NSString stringWithFormat:@"%@.refresh", NSBundle.mainBundle.bundleIdentifier];
+
+    if (@available(iOS 13.0, *)) {
+        // see: https://developer.apple.com/documentation/backgroundtasks/bgtaskscheduler?language=objc
+        [[BGTaskScheduler sharedScheduler] registerForTaskWithIdentifier:refreshTaskIdentifier
+                                                              usingQueue:nil
+                                                           launchHandler:^(__kindof BGTask * _Nonnull task) {
+            [self handleAppRefresh:task];
+        }];
+    } else {
+        [UIApplication.sharedApplication setMinimumBackgroundFetchInterval:UIApplicationBackgroundFetchIntervalMinimum];
+    }
+}
+
+- (void)scheduleAppRefresh API_AVAILABLE(ios(13.0))
+{
+    NSString *refreshTaskIdentifier = [NSString stringWithFormat:@"%@.refresh", NSBundle.mainBundle.bundleIdentifier];
+    
+    BGAppRefreshTaskRequest *request = [[BGAppRefreshTaskRequest alloc] initWithIdentifier:refreshTaskIdentifier];
+    request.earliestBeginDate = [NSDate dateWithTimeIntervalSinceNow:UIApplicationBackgroundFetchIntervalMinimum];
+    
+    NSError *error = nil;
+    [[BGTaskScheduler sharedScheduler] submitTaskRequest:request error:&error];
+    
+    if (error) {
+        NSLog(@"Failed to submit apprefresh request: %@", error);
+    }
+}
+
+- (void)handleAppRefresh:(BGTask *)task API_AVAILABLE(ios(13.0))
+{
+    NSLog(@"Performing background fetch -> handleAppRefresh");
+    
+    // With BGTasks (iOS >= 13) we need to schedule another refresh when running in background
+    [self scheduleAppRefresh];
+
+    [[NCRoomsManager sharedInstance] updateRoomsAndChatsUpdatingUserStatus:NO withCompletionBlock:^(NSError *error) {
+        if (error) {
+            [task setTaskCompletedWithSuccess:NO];
+        } else {
+            [task setTaskCompletedWithSuccess:YES];
+        }
+    }];
+}
+
+- (void)application:(UIApplication *)application performFetchWithCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler
+{
+    NSLog(@"Performing background fetch -> performFetchWithCompletionHandler");
+    
+    [[NCRoomsManager sharedInstance] updateRoomsAndChatsUpdatingUserStatus:NO withCompletionBlock:^(NSError *error) {
+        if (error) {
+            completionHandler(UIBackgroundFetchResultFailed);
+        } else {
+            completionHandler(UIBackgroundFetchResultNewData);
+        }
+    }];
+}
+
+
 @end

NextcloudTalk/Info.plist

@@ -5,6 +5,7 @@
 	<key>BGTaskSchedulerPermittedIdentifiers</key>
 	<array>
 		<string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
+		<string>$(PRODUCT_BUNDLE_IDENTIFIER).refresh</string>
 	</array>
 	<key>CFBundleDevelopmentRegion</key>
 	<string>en</string>

NextcloudTalk/NCRoomsManager.h

@@ -35,6 +35,9 @@ extern NSString * const NCRoomsManagerDidUpdateRoomNotification;
 // Call
 extern NSString * const NCRoomsManagerDidStartCallNotification;
 
+typedef void (^UpdateRoomsCompletionBlock)(NSArray *roomsWithNewMessages, NSError *error);
+typedef void (^UpdateRoomsAndChatsCompletionBlock)(NSError *error);
+
 @interface NCRoomController : NSObject
 
 @property (nonatomic, strong) NSString *userSessionId;
@@ -52,6 +55,7 @@ extern NSString * const NCRoomsManagerDidStartCallNotification;
 // Room
 - (NSArray *)roomsForAccountId:(NSString *)accountId witRealm:(RLMRealm *)realm;
 - (NCRoom *)roomWithToken:(NSString *)token forAccountId:(NSString *)accountId;
+- (void)updateRoomsAndChatsUpdatingUserStatus:(BOOL)updateStatus withCompletionBlock:(UpdateRoomsAndChatsCompletionBlock)block;
 - (void)updateRoomsUpdatingUserStatus:(BOOL)updateStatus;
 - (void)updateRoom:(NSString *)token;
 - (void)updateRoomLocal:(NCRoom *) room;

NextcloudTalk/NCRoomsManager.m

@@ -292,18 +292,58 @@ NSString * const NCRoomsManagerDidReceiveChatMessagesNotification   = @"ChatMess
 }
 
 - (void)updateRoomsUpdatingUserStatus:(BOOL)updateStatus
+{
+    [self updateRoomsUpdatingUserStatus:updateStatus withCompletionBlock:nil];
+}
+
+- (void)updateRoomsAndChatsUpdatingUserStatus:(BOOL)updateStatus withCompletionBlock:(UpdateRoomsAndChatsCompletionBlock)block
+{
+    [self updateRoomsUpdatingUserStatus:updateStatus withCompletionBlock:^(NSArray *roomsWithNewMessages, NSError *error) {
+        if (error) {
+            if (block) {
+                block(error);
+            }
+            
+            return;
+        }
+        
+        NSLog(@"Finished rooms update with %ld rooms with new messages", [roomsWithNewMessages count]);
+        dispatch_group_t chatUpdateGroup = dispatch_group_create();
+        
+        for (NCRoom *room in roomsWithNewMessages) {
+            //TODO: Update chat in rooms
+        }
+                
+        dispatch_group_notify(chatUpdateGroup, dispatch_get_main_queue(), ^{
+            // Notify backgroundFetch that we're finished
+            if (block) {
+                block(nil);
+            }
+        });
+    }];
+}
+
+- (void)updateRoomsUpdatingUserStatus:(BOOL)updateStatus withCompletionBlock:(UpdateRoomsCompletionBlock)block
 {
     TalkAccount *activeAccount = [[NCDatabaseManager sharedInstance] activeAccount];
     [[NCAPIController sharedInstance] getRoomsForAccount:activeAccount updateStatus:updateStatus withCompletionBlock:^(NSArray *rooms, NSError *error, NSInteger statusCode) {
         NSMutableDictionary *userInfo = [NSMutableDictionary new];
+        NSMutableArray *roomsWithNewMessages = [NSMutableArray new];
+        
         if (!error) {
             RLMRealm *realm = [RLMRealm defaultRealm];
             [realm transactionWithBlock:^{
                 // Add or update rooms
                 NSInteger updateTimestamp = [[NSDate date] timeIntervalSince1970];
                 for (NSDictionary *roomDict in rooms) {
-                    [self updateRoomWithDict:roomDict withAccount:activeAccount withTimestamp:updateTimestamp withRealm:realm];
+                    BOOL roomContainsNewMessages = [self updateRoomWithDict:roomDict withAccount:activeAccount withTimestamp:updateTimestamp withRealm:realm];
+                    
+                    if (roomContainsNewMessages) {
+                        NCRoom *room = [NCRoom roomWithDictionary:roomDict andAccountId:activeAccount.accountId];
+                        [roomsWithNewMessages addObject:room];
+                    }
                 }
+                
                 // Delete old rooms
                 NSPredicate *query = [NSPredicate predicateWithFormat:@"accountId = %@ AND lastUpdate != %ld", activeAccount.accountId, (long)updateTimestamp];
                 RLMResults *managedRoomsToBeDeleted = [NCRoom objectsWithPredicate:query];
@@ -320,9 +360,14 @@ NSString * const NCRoomsManagerDidReceiveChatMessagesNotification   = @"ChatMess
             [userInfo setObject:error forKey:@"error"];
             NSLog(@"Could not update rooms. Error: %@", error.description);
         }
+        
         [[NSNotificationCenter defaultCenter] postNotificationName:NCRoomsManagerDidUpdateRoomsNotification
                                                             object:self
                                                           userInfo:userInfo];
+        
+        if (block) {
+            block(roomsWithNewMessages, error);
+        }
     }];
 }
 
@@ -349,8 +394,10 @@ NSString * const NCRoomsManagerDidReceiveChatMessagesNotification   = @"ChatMess
     }];
 }
 
-- (void)updateRoomWithDict:(NSDictionary *)roomDict withAccount:(TalkAccount *)activeAccount withTimestamp:(NSInteger)timestamp withRealm:(RLMRealm *)realm
+- (BOOL)updateRoomWithDict:(NSDictionary *)roomDict withAccount:(TalkAccount *)activeAccount withTimestamp:(NSInteger)timestamp withRealm:(RLMRealm *)realm
 {
+    BOOL roomContainsNewMessages = NO;
+    
     NCRoom *room = [NCRoom roomWithDictionary:roomDict andAccountId:activeAccount.accountId];
     NSDictionary *messageDict = [roomDict objectForKey:@"lastMessage"];
     NCChatMessage *lastMessage = [NCChatMessage messageWithDictionary:messageDict andAccountId:activeAccount.accountId];
@@ -359,6 +406,10 @@ NSString * const NCRoomsManagerDidReceiveChatMessagesNotification   = @"ChatMess
     
     NCRoom *managedRoom = [NCRoom objectsWhere:@"internalId = %@", room.internalId].firstObject;
     if (managedRoom) {
+        if (room.lastActivity > managedRoom.lastActivity) {
+            roomContainsNewMessages = YES;
+        }
+        
         [NCRoom updateRoom:managedRoom withRoom:room];
     } else if (room) {
         [realm addObject:room];
@@ -371,6 +422,8 @@ NSString * const NCRoomsManagerDidReceiveChatMessagesNotification   = @"ChatMess
         NCChatController *chatController = [[NCChatController alloc] initForRoom:room];
         [chatController storeMessages:@[messageDict] withRealm:realm];
     }
+    
+    return roomContainsNewMessages;
 }
 
 - (void)updateRoomLocal:(NCRoom *)room