Notifications

NOTIFICATIONS (LOCAL — no server needed):

FRAMEWORK: UserNotifications — UNUserNotificationCenter.current()

PERMISSION STATES (CRITICAL — must handle ALL four states):

1. NOT DETERMINED: Call .requestAuthorization(options: [.alert, .badge, .sound]). System shows dialog.
2. AUTHORIZED: Schedule notifications normally.
3. DENIED: App CANNOT re-request permission. Must redirect user to System Settings.
4. PROVISIONAL: Quiet notifications — treat as authorized.

PERMISSION IS SYSTEM-CONTROLLED (CRITICAL):

• Notification authorization is owned by the SYSTEM, not the app.
• Once the user denies, the app has NO way to re-request — only the user can re-enable in System Settings.
• To open System Settings: UIApplication.shared.open(URL(string: UIApplication.openSettingsURLString)!)

UI THAT DISPLAYS NOTIFICATION STATUS (in ANY view — must handle ALL three states):

• .notDetermined: Show an "Enable Notifications" button that calls requestAuthorization(options: [.alert, .badge, .sound]). After the system dialog, re-check status and update UI.
• .authorized / .provisional: Show enabled state (e.g. "bell" icon, "Notifications are enabled" text). This is read-only — the user can disable in System Settings.
• .denied: Show disabled state ("bell.slash" icon) with an actionable "Open Settings" button that calls UIApplication.shared.open(URL(string: UIApplication.openSettingsURLString)!). Show helper text explaining the user must enable in System Settings.
• NEVER use a writable Toggle for notification permission — the app cannot grant/revoke it programmatically. Use buttons with state-specific actions instead.

RE-CHECK ON FOREGROUND (CRITICAL): Any view displaying notification status MUST re-check when the app returns to foreground. The user may have changed permissions in System Settings while the app was backgrounded.

.onReceive(NotificationCenter.default.publisher(for: UIApplication.willEnterForegroundNotification)) { _ in Task { let settings = await UNUserNotificationCenter.current().notificationSettings() isNotificationsEnabled = (settings.authorizationStatus == .authorized || settings.authorizationStatus == .provisional) } }

SCHEDULING:

• Local: UNMutableNotificationContent + UNNotificationRequest
• Time-based: UNTimeIntervalNotificationTrigger(timeInterval:repeats:)
• Calendar-based: UNCalendarNotificationTrigger(dateMatching:repeats:)
• Default to local notifications unless user explicitly asks for remote/push.

BADGE COUNT:

• Set via UNMutableNotificationContent().badge = NSNumber(value: count)
• Clear on app open: UIApplication.shared.applicationIconBadgeNumber = 0