Fix out-of-time notifications

ios/MullvadVPN/Notifications/Notification Providers/AccountExpiry.swift

@@ -7,37 +7,86 @@
 //
 
 import Foundation
+import MullvadTypes
 
 struct AccountExpiry {
+    enum Trigger {
+        case system, inApp
+
+        var dateIntervals: [Int] {
+            switch self {
+            case .system:
+                NotificationConfiguration.closeToExpirySystemTriggerIntervals
+            case .inApp:
+                NotificationConfiguration.closeToExpiryInAppTriggerIntervals
+            }
+        }
+    }
+
+    private let calendar = Calendar.current
+
     var expiryDate: Date?
 
-    var triggerDate: Date? {
-        guard let expiryDate else { return nil }
+    func nextTriggerDate(for trigger: Trigger) -> Date? {
+        let now = Date().secondsPrecision
+        let triggerDates = triggerDates(for: trigger)
 
-        return Calendar.current.date(
-            byAdding: .day,
-            value: -NotificationConfiguration.closeToExpiryTriggerInterval,
-            to: expiryDate
+        // Get earliest trigger date and remove one day. Since we want to count whole days, If first
+        // notification should trigger 3 days before account expiry, we need to start checking when
+        // there's (less than) 4 days left.
+        guard
+            let expiryDate,
+            let earliestDate = triggerDates.min(),
+            let earliestTriggerDate = calendar.date(byAdding: .day, value: -1, to: earliestDate),
+            now <= expiryDate.secondsPrecision,
+            now > earliestTriggerDate.secondsPrecision
+        else { return nil }
+
+        let datesByTimeToTrigger = triggerDates.filter { date in
+            now.secondsPrecision <= date.secondsPrecision // Ignore dates that have passed.
+        }.sorted { date1, date2 in
+            abs(date1.timeIntervalSince(now)) < abs(date2.timeIntervalSince(now))
+        }
+
+        return datesByTimeToTrigger.first
+    }
+
+    func daysRemaining(for trigger: Trigger) -> DateComponents? {
+        let nextTriggerDate = nextTriggerDate(for: trigger)
+        guard let expiryDate, let nextTriggerDate else { return nil }
+
+        let dateComponents = calendar.dateComponents(
+            [.day],
+            from: Date().secondsPrecision,
+            to: max(nextTriggerDate, expiryDate).secondsPrecision
         )
+
+        return dateComponents
     }
 
-    var formattedDuration: String? {
-        let now = Date()
+    func triggerDates(for trigger: Trigger) -> [Date] {
+        guard let expiryDate else { return [] }
 
-        guard
-            let expiryDate,
-            let triggerDate,
-            let duration = CustomDateComponentsFormatting.localizedString(
-                from: now,
-                to: expiryDate,
-                unitsStyle: .full
-            ),
-            now >= triggerDate,
-            now < expiryDate
-        else {
-            return nil
+        let dates = trigger.dateIntervals.compactMap {
+            calendar.date(
+                byAdding: .day,
+                value: -$0,
+                to: expiryDate
+            )
         }
 
-        return duration
+        return dates
+    }
+}
+
+private extension Date {
+    // Used to compare dates with a precision of a minimum of seconds.
+    var secondsPrecision: Date {
+        let dateComponents = Calendar.current.dateComponents(
+            [.second, .minute, .hour, .day, .month, .year, .calendar],
+            from: self
+        )
+
+        return dateComponents.date ?? self
     }
 }

ios/MullvadVPN/Notifications/Notification Providers/AccountExpiryInAppNotificationProvider.swift

@@ -38,24 +38,18 @@ final class AccountExpiryInAppNotificationProvider: NotificationProvider, InAppN
     // MARK: - InAppNotificationProvider
 
     var notificationDescriptor: InAppNotificationDescriptor? {
-        guard let duration = accountExpiry.formattedDuration else {
+        guard let durationText = remainingDaysText else {
             return nil
         }
 
         return InAppNotificationDescriptor(
             identifier: identifier,
             style: .warning,
-            title: NSLocalizedString(
-                "ACCOUNT_EXPIRY_INAPP_NOTIFICATION_TITLE",
-                value: "ACCOUNT CREDIT EXPIRES SOON",
-                comment: "Title for in-app notification, displayed within the last 3 days until account expiry."
-            ),
-            body: .init(string: String(
-                format: NSLocalizedString(
-                    "ACCOUNT_EXPIRY_INAPP_NOTIFICATION_BODY",
-                    value: "%@ left. Buy more credit.",
-                    comment: "Message for in-app notification, displayed within the last 3 days until account expiry."
-                ), duration
+            title: durationText,
+            body: NSAttributedString(string: NSLocalizedString(
+                "ACCOUNT_EXPIRY_IN_APP_NOTIFICATION_BODY",
+                value: "You can add more time via the account view or website to continue using the VPN.",
+                comment: "Title for in-app notification, displayed within the last X days until account expiry."
             ))
         )
     }
@@ -75,7 +69,7 @@ final class AccountExpiryInAppNotificationProvider: NotificationProvider, InAppN
     private func updateTimer() {
         timer?.cancel()
 
-        guard let triggerDate = accountExpiry.triggerDate else {
+        guard let triggerDate = accountExpiry.nextTriggerDate(for: .inApp) else {
             return
         }
 
@@ -105,3 +99,24 @@ final class AccountExpiryInAppNotificationProvider: NotificationProvider, InAppN
         invalidate()
     }
 }
+
+extension AccountExpiryInAppNotificationProvider {
+    private var remainingDaysText: String? {
+        guard
+            let expiryDate = accountExpiry.expiryDate,
+            let nextTriggerDate = accountExpiry.nextTriggerDate(for: .inApp),
+            let duration = CustomDateComponentsFormatting.localizedString(
+                from: nextTriggerDate,
+                to: expiryDate,
+                unitsStyle: .full
+            )
+        else { return nil }
+
+        return String(format: NSLocalizedString(
+            "ACCOUNT_EXPIRY_IN_APP_NOTIFICATION_TITLE",
+            tableName: "AccountExpiry",
+            value: "%@ left on this account",
+            comment: "Message for in-app notification, displayed within the last X days until account expiry."
+        ), duration).uppercased()
+    }
+}

ios/MullvadVPN/Notifications/Notification Providers/AccountExpirySystemNotificationProvider.swift

@@ -11,8 +11,9 @@ import MullvadSettings
 import UserNotifications
 
 final class AccountExpirySystemNotificationProvider: NotificationProvider, SystemNotificationProvider {
-    private var accountExpiry: Date?
+    private var accountExpiry = AccountExpiry()
     private var tunnelObserver: TunnelBlockObserver?
+    private var accountHasRecentlyExpired = false
 
     init(tunnelManager: TunnelManager) {
         super.init()
@@ -21,8 +22,16 @@ final class AccountExpirySystemNotificationProvider: NotificationProvider, Syste
             didLoadConfiguration: { [weak self] tunnelManager in
                 self?.invalidate(deviceState: tunnelManager.deviceState)
             },
-            didUpdateDeviceState: { [weak self] _, deviceState, _ in
-                self?.invalidate(deviceState: deviceState)
+            didUpdateDeviceState: { [weak self] tunnelManager, deviceState, previousDeviceState in
+                guard let self else { return }
+
+                checkAccountExpiry(
+                    tunnelStatus: tunnelManager.tunnelStatus,
+                    deviceState: deviceState,
+                    previousDeviceState: previousDeviceState
+                )
+
+                invalidate(deviceState: tunnelManager.deviceState)
             }
         )
 
@@ -38,22 +47,16 @@ final class AccountExpirySystemNotificationProvider: NotificationProvider, Syste
     // MARK: - SystemNotificationProvider
 
     var notificationRequest: UNNotificationRequest? {
-        guard let trigger else { return nil }
+        let trigger = accountHasRecentlyExpired ? triggerExpiry : triggerCloseToExpiry
+
+        guard let trigger, let formattedRemainingDurationBody else {
+            return nil
+        }
 
         let content = UNMutableNotificationContent()
-        content.title = NSLocalizedString(
-            "ACCOUNT_EXPIRY_SYSTEM_NOTIFICATION_TITLE",
-            tableName: "AccountExpiry",
-            value: "Account credit expires soon",
-            comment: "Title for system account expiry notification, fired 3 days prior to account expiry."
-        )
-        content.body = NSLocalizedString(
-            "ACCOUNT_EXPIRY_SYSTEM_NOTIFICATION_BODY",
-            tableName: "AccountExpiry",
-            value: "Account credit expires in 3 days. Buy more credit.",
-            comment: "Message for system account expiry notification, fired 3 days prior to account expiry."
-        )
-        content.sound = UNNotificationSound.default
+        content.title = formattedRemainingDurationTitle
+        content.body = formattedRemainingDurationBody
+        content.sound = .default
 
         return UNNotificationRequest(
             identifier: identifier.domainIdentifier,
@@ -74,33 +77,131 @@ final class AccountExpirySystemNotificationProvider: NotificationProvider, Syste
 
     // MARK: - Private
 
-    private var trigger: UNNotificationTrigger? {
-        guard let accountExpiry else { return nil }
+    private var triggerCloseToExpiry: UNNotificationTrigger? {
+        guard let triggerDate = accountExpiry.nextTriggerDate(for: .system) else { return nil }
 
-        guard let triggerDate = Calendar.current.date(
-            byAdding: .day,
-            value: -NotificationConfiguration.closeToExpiryTriggerInterval,
-            to: accountExpiry
-        ) else { return nil }
+        let dateComponents = Calendar.current.dateComponents(
+            [.second, .minute, .hour, .day, .month, .year],
+            from: triggerDate
+        )
 
-        // Do not produce notification if less than 3 days left till expiry
-        guard triggerDate > Date() else { return nil }
+        return UNCalendarNotificationTrigger(dateMatching: dateComponents, repeats: false)
+    }
 
-        // Create date components for calendar trigger
+    private var triggerExpiry: UNNotificationTrigger {
+        // When scheduling a user notification we need to make sure that the date has not passed
+        // when it's actually added to the system. Giving it a one second leeway lets us be sure
+        // that this is the case.
         let dateComponents = Calendar.current.dateComponents(
             [.second, .minute, .hour, .day, .month, .year],
-            from: triggerDate
+            from: Date().addingTimeInterval(1)
         )
 
         return UNCalendarNotificationTrigger(dateMatching: dateComponents, repeats: false)
     }
 
     private var shouldRemovePendingOrDeliveredRequests: Bool {
-        accountExpiry == nil
+        return accountExpiry.expiryDate == nil
+    }
+
+    // Adding extra security here to make sure we don't accidentally spam users with notifications.
+    //
+    // Basically making sure that:
+    // 1. Blocked state is because of account expiry, so that we don't trigger for any kind of blocked state.
+    // 2. Current state is blocked state.
+    // 3. Previous expiry state is not the same as current expiry state. This last check can't decide alone if
+    //    we went from expired -> not expired, or the other way around. That's why we combine 2) and 3).
+    private func checkAccountExpiry(
+        tunnelStatus: TunnelStatus,
+        deviceState: DeviceState,
+        previousDeviceState: DeviceState
+    ) {
+        var blockedStateByExpiredAccount = false
+        if case .accountExpired = tunnelStatus.observedState.blockedState?.reason {
+            blockedStateByExpiredAccount = true
+        }
+
+        let accountHasExpired = deviceState.accountData?.isExpired == true
+        let accountHasRecentlyExpired = accountHasExpired != previousDeviceState.accountData?.isExpired
+
+        self.accountHasRecentlyExpired = blockedStateByExpiredAccount && accountHasExpired && accountHasRecentlyExpired
     }
 
     private func invalidate(deviceState: DeviceState) {
-        accountExpiry = deviceState.accountData?.expiry
+        accountExpiry.expiryDate = deviceState.accountData?.expiry
         invalidate()
     }
 }
+
+extension AccountExpirySystemNotificationProvider {
+    private var formattedRemainingDurationTitle: String {
+        accountHasRecentlyExpired
+            ? NSLocalizedString(
+                "ACCOUNT_EXPIRY_SYSTEM_NOTIFICATION_TITLE",
+                tableName: "AccountExpiry",
+                value: "Account credit has expired",
+                comment: "Title for system account expiry notification, fired on account expiry."
+            )
+            : NSLocalizedString(
+                "ACCOUNT_EXPIRY_SYSTEM_NOTIFICATION_TITLE",
+                tableName: "AccountExpiry",
+                value: "Account credit expires soon",
+                comment: "Title for system account expiry notification, fired X days prior to account expiry."
+            )
+    }
+
+    private var formattedRemainingDurationBody: String? {
+        if accountHasRecentlyExpired {
+            return expiredText
+        }
+
+        switch accountExpiry.daysRemaining(for: .system)?.day {
+        case .none:
+            return nil
+        case 1:
+            return singleDayText
+        default:
+            return multipleDaysText
+        }
+    }
+
+    private var expiredText: String {
+        NSLocalizedString(
+            "ACCOUNT_EXPIRY_SYSTEM_NOTIFICATION_BODY",
+            tableName: "AccountExpiry",
+            value: """
+            Blocking internet: Your time on this account has expired. To continue using the internet, \
+            please add more time or disconnect the VPN.
+            """,
+            comment: "Message for in-app notification, displayed on account expiry while connected to VPN."
+        )
+    }
+
+    private var singleDayText: String {
+        NSLocalizedString(
+            "ACCOUNT_EXPIRY_SYSTEM_NOTIFICATION_BODY",
+            tableName: "AccountExpiry",
+            value: "You have one day left on this account. Please add more time to continue using the VPN.",
+            comment: "Message for in-app notification, displayed within the last 1 day until account expiry."
+        )
+    }
+
+    private var multipleDaysText: String? {
+        guard
+            let expiryDate = accountExpiry.expiryDate,
+            let nextTriggerDate = accountExpiry.nextTriggerDate(for: .system),
+            let duration = CustomDateComponentsFormatting.localizedString(
+                from: nextTriggerDate,
+                to: expiryDate,
+                unitsStyle: .full
+            )
+        else { return nil }
+
+        return String(format: NSLocalizedString(
+            "ACCOUNT_EXPIRY_SYSTEM_NOTIFICATION_BODY",
+            tableName: "AccountExpiry",
+            value: "You have %@ left on this account.",
+            comment: "Message for in-app notification, displayed within the last X days until account expiry."
+        ), duration.lowercased())
+    }
+}

ios/MullvadVPN/Notifications/Notification Providers/NotificationConfiguration.swift

@@ -10,10 +10,16 @@ import Foundation
 
 enum NotificationConfiguration {
     /**
-     Duration measured in days, before the account expiry, when notification is scheduled to remind user to add more
-     time on account.
+     Duration measured in days, before the account expiry, when a system notification is scheduled to remind user
+     to add more time on account.
      */
-    static let closeToExpiryTriggerInterval = 3
+    static let closeToExpirySystemTriggerIntervals = [3, 1]
+
+    /**
+     Duration measured in days, before the account expiry, when an in-app notification is scheduled to remind user
+     to add more time on account.
+     */
+    static let closeToExpiryInAppTriggerIntervals: [Int] = [3, 2, 1, 0]
 
     /**
      Time interval measured in seconds at which to refresh account expiry in-app notification, which reformats