import UIKit
  import Firebase
  import UserNotifications

  @UIApplicationMain
  class AppDelegate: UIResponder, UIApplicationDelegate, UNUserNotificationCenterDelegate {

      var window: UIWindow?


      func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
          // Override point for customization after application launch.
          FirebaseApp.configure()

          askAndRegisterForPushNotif()
          return true
      }

      func askAndRegisterForPushNotif() {
          let unAuthCenter = UNUserNotificationCenter.current()
          unAuthCenter.requestAuthorization(options: [.alert, .sound, .badge]) {
              (sucess, error) in
              if sucess {
                  DispatchQueue.main.async {
                      unAuthCenter.delegate = self
                      let appDelegate = UIApplication.shared
                      appDelegate.registerForRemoteNotifications()
                      print("Push granted: \(sucess)")
                  }
              }

              if error != nil {
                 print(error?.localizedDescription)
              }

          }
      }

      func application(_ application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {
          print("registered")
      }

      func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {
          print("received notif")
          completionHandler()
      }

      func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {

          let options: UNNotificationPresentationOptions = [.alert, .sound]
          completionHandler(options)
      }

  }