Add method to retrieve authorization status

Summary:
Changelog:
[iOS][Added] - Adds an ability to retrieve the notifications authorization status from JavaScript side.

Differential Revision: D27426952

fbshipit-source-id: 84a1eae1ff8c8f9f7601c7479745002c21178850

Author: Lucas Santos

Libraries/PushNotificationIOS/NativePushNotificationManagerIOS.js

@@ -65,6 +65,9 @@ export interface Spec extends TurboModule {
   +getDeliveredNotifications: (
     callback: (notification: Array<Notification>) => void,
   ) => void;
+  +getAuthorizationStatus: (
+    callback: (authorizationStatus: number) => void,
+  ) => void;
   +addListener: (eventType: string) => void;
   +removeListeners: (count: number) => void;
 }

Libraries/PushNotificationIOS/PushNotificationIOS.js

@@ -399,6 +399,20 @@ class PushNotificationIOS {
     );
   }
 
+  /**
+   * This method returns a promise that resolves to notification authorization status.
+   */
+  static getAuthorizationStatus(
+    callback: (authorizationStatus: number) => void,
+  ): void {
+    invariant(
+      NativePushNotificationManagerIOS,
+      'PushNotificationManager is not available.',
+    );
+
+    NativePushNotificationManagerIOS.getAuthorizationStatus(callback);
+  }
+
   /**
    * You will never need to instantiate `PushNotificationIOS` yourself.
    * Listening to the `notification` event and invoking

Libraries/PushNotificationIOS/RCTPushNotificationManager.mm

@@ -471,6 +471,14 @@ - (void)handleRemoteNotificationRegistrationError:(NSNotification *)notification
   }];
 }
 
+RCT_EXPORT_METHOD(getAuthorizationStatus:(RCTResponseSenderBlock)callback)
+{
+  UNUserNotificationCenter *center = [UNUserNotificationCenter currentNotificationCenter];
+  [center getNotificationSettingsWithCompletionHandler:^(UNNotificationSettings *_Nonnull settings)  {
+    callback(@[@(settings.authorizationStatus)]);
+  }];
+}
+
 #else // TARGET_OS_UIKITFORMAC
 
 RCT_EXPORT_METHOD(onFinishRemoteNotification:(NSString *)notificationId fetchResult:(NSString *)fetchResult)
@@ -551,6 +559,11 @@ - (void)handleRemoteNotificationRegistrationError:(NSNotification *)notification
   RCTLogError(@"Not implemented: %@", NSStringFromSelector(_cmd));
 }
 
+RCT_EXPORT_METHOD(getAuthorizationStatus:(RCTResponseSenderBlock)callback)
+{
+  RCTLogError(@"Not implemented: %@", NSStringFromSelector(_cmd));
+}
+
 - (NSArray<NSString *> *)supportedEvents
 {
   return @[];