import SwiftUI
import BinaryCodable

@main
struct FlurSchnapsApp: App {
    
    @UIApplicationDelegateAdaptor(AppDelegate.self)
    var appDelegate
    
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}

class AppDelegate: NSObject, UIApplicationDelegate {
    
    @AppStorage("deviceToken")
    var pushToken: Data?
    
    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey : Any]? = nil) -> Bool {
        
        // For iOS 10 display notification (sent via APNS)
        UNUserNotificationCenter.current().delegate = self


        UIApplication.shared.registerForRemoteNotifications()
        return true
    }
    
    func application(_ application: UIApplication,
                     didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {
        let token = deviceToken.hexEncoded
        print("Registered for remote notifications with token: \(token)")
        uploadNewDeviceToken(deviceToken)
    }
    
    func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable: Any],
                     fetchCompletionHandler completionHandler: @escaping (UIBackgroundFetchResult) -> Void) {
        
        print(userInfo)
        
        completionHandler(UIBackgroundFetchResult.newData)
    }
    
    private func uploadNewDeviceToken(_ token: Data) {
        if token == pushToken {
            // Device token unchanged
            return
        }
        
        Task {
            let tokenUpload = TokenUpload(currentToken: token, previousToken: pushToken)
            let data: Data
            do {
                data = try BinaryEncoder().encode(tokenUpload)
                
            } catch {
                print("Failed to encode token upload")
                return
            }
            let result: URLResponse
            do {
                var request = URLRequest(url: URL(string: "https://christophhagen.de/schnaps/token")!)
                request.httpMethod = "POST"
                (_, result) = try await URLSession.shared.upload(for: request, from: data)
            } catch {
                print("Failed to upload token: \(error)")
                return
            }
            guard let response = result as? HTTPURLResponse else {
                print("Invalid response \(result)")
                return
            }
            guard response.statusCode == 200 else {
                print("Invalid response to token upload: \(response.statusCode)")
                return
            }
            print("Push token uploaded")
            DispatchQueue.main.async {
                self.pushToken = token
            }
        }
        // Upload new token, possibly with old one
    }
}

extension AppDelegate: UNUserNotificationCenterDelegate {
    
    // Receive displayed notifications for iOS 10 devices.
    func userNotificationCenter(_ center: UNUserNotificationCenter,
                                willPresent notification: UNNotification,
                                withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
        let userInfo = notification.request.content.userInfo
        print(userInfo)
        
        // Change this to your preferred presentation option
        completionHandler([[.banner, .badge, .sound]])
    }
    
    
    func application(_ application: UIApplication, didFailToRegisterForRemoteNotificationsWithError error: Error) {
        
    }
    
    func userNotificationCenter(_ center: UNUserNotificationCenter,
                                didReceive response: UNNotificationResponse,
                                withCompletionHandler completionHandler: @escaping () -> Void) {
        let userInfo = response.notification.request.content.userInfo
        print(userInfo)
        completionHandler()
    }
}