feat: Handle critical notifications in payload extension, due to FCM legacy api limitation

Sources/EQNNotificationService/NotificationService.m

@@ -28,7 +28,6 @@ static NSString * const EQNSoundNotificationEQN = @"alert_sound.wav";
     UNMutableNotificationContent* content = [[UNMutableNotificationContent alloc] init];
     content.title = [NSString localizedUserNotificationStringForKey:request.content.title arguments:nil];
     content.body = [NSString localizedUserNotificationStringForKey:request.content.body arguments:nil];
-    content.sound = [UNNotificationSound defaultSound];
     
     self.bestAttemptContent.title = content.title;
     self.bestAttemptContent.body = content.body;
@@ -44,9 +43,16 @@ static NSString * const EQNSoundNotificationEQN = @"alert_sound.wav";
     
     NSString *iconName = @"";
     if ([notificationType isEqualToString:@"eqn"]) {
-        UNNotificationSound *sound = [UNNotificationSound soundNamed:EQNSoundNotificationEQN];
-        self.bestAttemptContent.sound = sound;
-        
+        // !!WORKAROUND
+        // this is a workaround to use critical alerts with legacy FCM api
+        // when the server implementation will be migrated to Firebase v1 APIs, this could be removed
+        BOOL isCritical = [[userInfo objectForKey:@"critical"] boolValue];
+        if (isCritical) {
+            self.bestAttemptContent.sound = [UNNotificationSound criticalSoundNamed:EQNSoundNotificationEQN withAudioVolume:1.0];
+        } else {
+            self.bestAttemptContent.sound = [UNNotificationSound soundNamed:EQNSoundNotificationEQN];
+        }
+                
         NSString *intensity = [userInfo objectForKey:@"intensity"];
         switch ([intensity intValue]) {
             case 0: