Keep a previous badge count as well as current

* When a notification foreground display is cancelled, the badge count in that notification (if any) does not apply. We have to revert our cached badge count back to the previous. We store the previous as we cannot use a getter for badge count anymore.

iOS_SDK/OneSignalSDK/OneSignalCore/Source/OneSignalBadgeHelpers.h

@@ -28,5 +28,5 @@
 #import <Foundation/Foundation.h>
 
 @interface OneSignalBadgeHelpers : NSObject
-+ (void)updateCachedBadgeValue:(NSInteger)value;
++ (void)updateCachedBadgeValue:(NSInteger)value usePreviousBadgeCount:(BOOL)usePrevious;
 @end

iOS_SDK/OneSignalSDK/OneSignalCore/Source/OneSignalBadgeHelpers.m

@@ -30,9 +30,23 @@
 #import "OneSignalCommonDefines.h"
 
 @implementation OneSignalBadgeHelpers
-+ (void)updateCachedBadgeValue:(NSInteger)value {
+
+/**
+ Store a previous badge count so that we can revert to this cached value when a notification display is cancelled.
+ When `usePreviousBadgeCount` is `true`, the `value` passed to this method will be unused.
+ */
++ (void)updateCachedBadgeValue:(NSInteger)value usePreviousBadgeCount:(BOOL)usePrevious {
     // Since badge logic can be executed in an extension, we need to use app groups to get
     // a shared NSUserDefaults from the app group suite name
-    [OneSignalUserDefaults.initShared saveIntegerForKey:ONESIGNAL_BADGE_KEY withValue:value];
+    if (usePrevious) {
+        // Keep the PREVIOUS_ONESIGNAL_BADGE_KEY value unchanged
+        NSInteger previousBadgeCount = [OneSignalUserDefaults.initShared getSavedIntegerForKey:PREVIOUS_ONESIGNAL_BADGE_KEY defaultValue:0];
+        [OneSignalUserDefaults.initShared saveIntegerForKey:ONESIGNAL_BADGE_KEY withValue:previousBadgeCount];
+    } else {
+        NSInteger previousBadgeCount = [OneSignalUserDefaults.initShared getSavedIntegerForKey:ONESIGNAL_BADGE_KEY defaultValue:0];
+        [OneSignalUserDefaults.initShared saveIntegerForKey:PREVIOUS_ONESIGNAL_BADGE_KEY withValue:previousBadgeCount];
+        [OneSignalUserDefaults.initShared saveIntegerForKey:ONESIGNAL_BADGE_KEY withValue:value];
+    }
 }
+
 @end

iOS_SDK/OneSignalSDK/OneSignalCore/Source/OneSignalCommonDefines.h

@@ -159,6 +159,8 @@
 #define ONESIGNAL_DISABLE_BADGE_CLEARING @"OneSignal_disable_badge_clearing"
 #define ONESIGNAL_APP_GROUP_NAME_KEY @"OneSignal_app_groups_key"
 #define ONESIGNAL_BADGE_KEY @"onesignalBadgeCount"
+/// Store the previous badge count to read for a cancelled notification display event
+#define PREVIOUS_ONESIGNAL_BADGE_KEY @"previousOnesignalBadgeCount"
 
 // Firebase
 #define ONESIGNAL_FB_ENABLE_FIREBASE @"OS_ENABLE_FIREBASE_ANALYTICS"

iOS_SDK/OneSignalSDK/OneSignalExtension/OneSignalExtensionBadgeHandler.m

@@ -35,7 +35,7 @@ + (void)handleBadgeCountWithNotificationRequest:(UNNotificationRequest *)request
     //make sure the OneSignal cached value is updated to this value
     if (!notification.badgeIncrement) {
         if (notification.hasBadge)
-            [OneSignalBadgeHelpers updateCachedBadgeValue:notification.badge];
+            [OneSignalBadgeHelpers updateCachedBadgeValue:notification.badge usePreviousBadgeCount:false];
 
         return;
     }
@@ -50,7 +50,7 @@ + (void)handleBadgeCountWithNotificationRequest:(UNNotificationRequest *)request
 
     replacementContent.badge = @(currentValue);
 
-    [OneSignalBadgeHelpers updateCachedBadgeValue:currentValue];
+    [OneSignalBadgeHelpers updateCachedBadgeValue:currentValue usePreviousBadgeCount:false];
 }
 
 + (NSInteger)currentCachedBadgeValue {

iOS_SDK/OneSignalSDK/OneSignalNotifications/Categories/UNUserNotificationCenter+OneSignalNotifications.m

@@ -179,7 +179,7 @@ - (void)onesignalGetNotificationSettingsWithCompletionHandler:(void(^)(UNNotific
  necessary as there is no equivalent "getBadgeCount" method available.
  */
 - (void)onesignalSetBadgeCount:(NSInteger)badge withCompletionHandler:(void(^)(NSError *error))completionHandler {
-    [OneSignalBadgeHelpers updateCachedBadgeValue:badge];
+    [OneSignalBadgeHelpers updateCachedBadgeValue:badge usePreviousBadgeCount:false];
     [self onesignalSetBadgeCount:badge withCompletionHandler:completionHandler];
 }
 

iOS_SDK/OneSignalSDK/OneSignalNotifications/OSNotification+OneSignal.m

@@ -76,8 +76,8 @@ - (void)complete:(OSDisplayableNotification *)notification {
      reset the badge count to the value prior to receipt of this notif
      */
     if (!notification) {
-        NSInteger previousBadgeCount = [UIApplication sharedApplication].applicationIconBadgeNumber;
-        [OneSignalBadgeHelpers updateCachedBadgeValue:previousBadgeCount];
+        // The badge count value of -99 will not be used, the previous badge count will be set
+        [OneSignalBadgeHelpers updateCachedBadgeValue:-99 usePreviousBadgeCount:true];
     }
     if (_completion) {
         _completion(notification);

iOS_SDK/OneSignalSDK/Source/OneSignal.m

@@ -809,7 +809,7 @@ + (void)load {
     We swizzle the 'setApplicationIconBadgeNumber()' to intercept these calls so we always know the latest count
 */
 - (void)onesignalSetApplicationIconBadgeNumber:(NSInteger)badge {
-    [OneSignalBadgeHelpers updateCachedBadgeValue:badge];
+    [OneSignalBadgeHelpers updateCachedBadgeValue:badge usePreviousBadgeCount:false];
     [self onesignalSetApplicationIconBadgeNumber:badge];
 }