Manager to handle local notifications.

LocalNotificationManager.Swift

import UIKit
import UserNotifications

class LocalNotificationManager {
  
  var notifications = [Notification]()
  
  func scheduledNotifications(completion: ([Notification])->()) {
    if #available(iOS 10.0, *) {
      UNUserNotificationCenter.current().getPendingNotificationRequests { notifications in
        print(notifications)
        // let notificationObject = notifications.map ({ item -> Notification in
  
          // let notification = Notification(id: item.identifier, title: item.content.title, datetime: <#T##DateComponents#>)
        // })
      }
      completion([])
    } else {
      // Fallback on earlier versions
      UIApplication.shared.scheduledLocalNotifications?.forEach { notification in
        print(notification)
        completion([])
      }
    }
  }
  
  func schedule() {
    if #available(iOS 10.0, *) {
      UNUserNotificationCenter.current().getNotificationSettings { settings in
        switch settings.authorizationStatus {
        case .notDetermined:
          self.requestAuthorization()
        case .authorized, .provisional:
          self.scheduleNotifications()
        default:
          break // Do nothing
        }
      }
    } else {
      // Fallback on earlier versions
      
    }
  }
}

/// MARK:- PRIVATE METHODS
extension LocalNotificationManager {
  private func requestAuthorization(){
    if #available(iOS 10.0, *) {
      UNUserNotificationCenter.current().requestAuthorization(options: [.alert, .badge, .sound]) { granted, error in
        if granted == true && error == nil {
          self.scheduleNotifications()
        }
      }
    } else {
      // Fallback on earlier versions
      let settings: UIUserNotificationSettings =
          UIUserNotificationSettings(types: [.alert, .badge, .sound], categories: nil)
      UIApplication.shared.registerUserNotificationSettings(settings)
    }
  }
  
  private func scheduleNotifications() {
    if #available(iOS 10.0, *) {
      notifications.forEach { item in
        let content = UNMutableNotificationContent()
        content.title = item.title
        content.sound = .default
        content.userInfo = ["type": "local"]
        let trigger = UNCalendarNotificationTrigger(dateMatching: item.datetime, repeats: false)
        let request = UNNotificationRequest(identifier: item.id, content: content, trigger: trigger)
        UNUserNotificationCenter.current().add(request) { error in
          guard error == nil else { return }
          print("Notification scheduled! --- ID = \(item.id)")
        }
      }
    } else {
      // Fallback on earlier versions
      let notificationsObject = notifications.map({ item -> UILocalNotification in
        let notification = UILocalNotification()
        notification.alertTitle = item.title
        notification.userInfo = ["type": "local"]
        notification.fireDate = item.datetime.date
        return notification
      })
      UIApplication.shared.cancelAllLocalNotifications()
      UIApplication.shared.scheduledLocalNotifications = notificationsObject
    }
  }
}


struct Notification {
  var id: String
  var title: String
  var datetime: DateComponents
}