Proper VPN simulator with notifications, etc.

main/Push Notifications/PushNotification.swift

@@ -0,0 +1,153 @@
+import UserNotifications
+
+struct PushNotification {
+	
+	enum Identifier: String {
+		case YouShallRecordMoreReminder
+		case CantStopMeNowReminder
+		case RestInPeaceTombstone
+		case AllConnectionAlertNotifications
+	}
+	
+	static func allowed(_ closure: @escaping (NotificationRequestState) -> Void) {
+		guard #available(iOS 10, *) else { return }
+		
+		UNUserNotificationCenter.current().getNotificationSettings { settings in
+			let state = NotificationRequestState(settings.authorizationStatus)
+			DispatchQueue.main.async {
+				closure(state)
+			}
+		}
+	}
+	
+	/// Available in iOS 12+
+	static func requestProvisionalOrDoNothing(_ closure: @escaping (Bool) -> Void) {
+		guard #available(iOS 12, *) else { return closure(false) }
+		
+		let opt: UNAuthorizationOptions = [.alert, .sound, .badge, .provisional, .providesAppNotificationSettings]
+		UNUserNotificationCenter.current().requestAuthorization(options: opt) { granted, _ in
+			DispatchQueue.main.async {
+				closure(granted)
+			}
+		}
+	}
+	
+	static func requestAuthorization(_ closure: @escaping (Bool) -> Void) {
+		guard #available(iOS 10, *) else { return }
+		
+		var opt: UNAuthorizationOptions = [.alert, .sound, .badge]
+		if #available(iOS 12, *) {
+			opt.formUnion(.providesAppNotificationSettings)
+		}
+		UNUserNotificationCenter.current().requestAuthorization(options: opt) { granted, _ in
+			DispatchQueue.main.async {
+				closure(granted)
+			}
+		}
+	}
+	
+	static func hasPending(_ ident: Identifier, _ closure: @escaping (Bool) -> Void) {
+		guard #available(iOS 10, *) else { return }
+		
+		UNUserNotificationCenter.current().getPendingNotificationRequests {
+			let hasIt = $0.contains { $0.identifier == ident.rawValue }
+			DispatchQueue.main.async {
+				closure(hasIt)
+			}
+		}
+	}
+	
+	static func cancel(_ ident: Identifier, keepDelivered: Bool = false) {
+		guard #available(iOS 10, *) else { return }
+		
+		let center = UNUserNotificationCenter.current()
+		guard ident != .AllConnectionAlertNotifications else {
+			// remove all connection alert notifications while
+			// keeping general purpose reminder notifications
+			center.getDeliveredNotifications {
+				var list = $0.map { $0.request.identifier }
+				list.removeAll { !$0.contains(".") } // each domain (or IP) has a dot
+				center.removeDeliveredNotifications(withIdentifiers: list)
+				// no need to do the same for pending since con-alerts are always immediate
+			}
+			return
+		}
+		center.removePendingNotificationRequests(withIdentifiers: [ident.rawValue])
+		if !keepDelivered {
+			center.removeDeliveredNotifications(withIdentifiers: [ident.rawValue])
+		}
+	}
+	
+	@available(iOS 10.0, *)
+	static func schedule(_ ident: Identifier, content: UNNotificationContent, trigger: UNNotificationTrigger? = nil, waitUntilDone: Bool = false) {
+		schedule(ident.rawValue, content: content, trigger: trigger, waitUntilDone: waitUntilDone)
+	}
+	
+	@available(iOS 10.0, *)
+	static func schedule(_ ident: String, content: UNNotificationContent, trigger: UNNotificationTrigger? = nil, waitUntilDone: Bool = false) {
+		let req = UNNotificationRequest(identifier: ident, content: content, trigger: trigger)
+		waitUntilDone ? req.pushAndWait() : req.push()
+	}
+}
+
+
+// MARK: - Reminder Alerts
+
+extension PushNotification {
+	/// Auto-check preferences whether `withText` is set, then schedule notification to 5 min in the future.
+	static func scheduleRestartReminderBanner() {
+		guard #available(iOS 10, *), PrefsShared.RestartReminder.WithText else { return }
+		
+		schedule(.CantStopMeNowReminder,
+				 content: .make("AppCheck disabled",
+								body: "AppCheck can't monitor network traffic because VPN has stopped.",
+								sound: .from(string: PrefsShared.RestartReminder.Sound)),
+				 trigger: .make(Date(timeIntervalSinceNow: 5 * 60)),
+				 waitUntilDone: true)
+	}
+	
+	/// Auto-check preferences whether `withBadge` is set, then post badge immediatelly.
+	/// - Parameter on: If `true`, set `1` on app icon. If `false`, remove badge on app icon.
+	static func scheduleRestartReminderBadge(on: Bool) {
+		guard #available(iOS 10, *), PrefsShared.RestartReminder.WithBadge else { return }
+		
+		schedule(.RestInPeaceTombstone, content: .makeBadge(on ? 1 : 0), waitUntilDone: true)
+	}
+}
+
+
+// MARK: - Connection Alerts
+
+extension PushNotification {
+	static private let queue = ThrottledBatchQueue<String>(0.5, using: .init(label: "PSINotificationQueue", qos: .default, target: .global()))
+	
+	/// Post new notification with given domain name. If notification already exists, increase occurrence count.
+	/// - Parameter domain: Used in the description and as notification identifier.
+	@available(iOS 10.0, *)
+	static func scheduleConnectionAlert(_ domain: String, sound: UNNotificationSound?) {
+		queue.addDelayed(domain) { batch in
+			let groupSum = batch.reduce(into: [:]) { $0[$1] = ($0[$1] ?? 0) + 1 }
+			scheduleConnectionAlertMulti(groupSum, sound: sound)
+		}
+	}
+	
+	/// Internal method to post a batch of counted domains.
+	@available(iOS 10.0, *)
+	static private func scheduleConnectionAlertMulti(_ group: [String: Int], sound: UNNotificationSound?) {
+		UNUserNotificationCenter.current().getDeliveredNotifications { delivered in
+			for (dom, count) in group {
+				let num: Int
+				if let prev = delivered.first(where: { $0.request.identifier == dom })?.request.content {
+					if let p = prev.body.split(separator: "×").first, let i = Int(p) {
+						num = count + i
+					} else {
+						num = count + 1
+					}
+				} else {
+					num = count
+				}
+				schedule(dom, content: .make("DNS connection", body: num > 1 ? "\(num)× \(dom)" : dom, sound: sound))
+			}
+		}
+	}
+}