Implement iOS Push Notifications

As an iOS developer, I need to implement and manage push notifications for my application so that I can engage users effectively. This includes setting up remote notifications, handling registration, processing incoming payloads, and optimizing delivery.

import UserNotifications
import UIKit

class AppDelegate: UIResponder, UIApplicationDelegate {
    
    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        
        // Request notification permissions
        UNUserNotificationCenter.current().delegate = self
        let authOptions: UNAuthorizationOptions = [.alert, .badge, .sound]
        
        UNUserNotificationCenter.current().requestAuthorization(options: authOptions) { granted, error in
            if granted {
                DispatchQueue.main.async {
                    UIApplication.shared.registerForRemoteNotifications()
                }
            }
        }
        
        return true
    }
    
    // Handle successful registration
    func application(_ application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {
        let tokenParts = deviceToken.map { data in String(format: "%02.2hhx", data) }
        let token = tokenParts.joined()
        print("Device Token: \(token)")
        
        // Send token to your server
        sendTokenToServer(token: token)
    }
    
    // Handle registration failure
    func application(_ application: UIApplication, didFailToRegisterForRemoteNotificationsWithError error: Error) {
        print("Failed to register for remote notifications: \(error.localizedDescription)")
    }
}