social-app/apps/test/features/calendar/reminders/reminder_notification_callbacks_test.dart

import 'dart:io';

import 'package:flutter_local_notifications/flutter_local_notifications.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:social_app/core/notifications/reminder_notification_callbacks.dart';

void main() {
  setUp(() async {
    SharedPreferences.setMockInitialValues({});
    await ReminderNotificationCallbacks.resetForTest();
  });

  test('contains top-level vm entry-point background callback', () async {
    final source = await File(
      'lib/core/notifications/reminder_notification_callbacks.dart',
    ).readAsString();

    expect(source, contains("@pragma('vm:entry-point')"));
    expect(source, contains('Future<void> reminderNotificationTapBackground('));
  });

  test(
    'dispatches foreground and background responses to bound handler',
    () async {
      final handledIds = <int?>[];
      await ReminderNotificationCallbacks.bindResponseHandler((response) async {
        handledIds.add(response.id);
      });

      await ReminderNotificationCallbacks.onForegroundResponse(
        NotificationResponse(
          notificationResponseType:
              NotificationResponseType.selectedNotificationAction,
          id: 10,
        ),
      );
      await reminderNotificationTapBackground(
        NotificationResponse(
          notificationResponseType:
              NotificationResponseType.selectedNotificationAction,
          id: 20,
        ),
      );

      expect(handledIds, <int?>[10, 20]);
    },
  );

  test(
    'queues background response when handler is unbound and drains later',
    () async {
      await reminderNotificationTapBackground(
        NotificationResponse(
          notificationResponseType:
              NotificationResponseType.selectedNotificationAction,
          id: 99,
        ),
      );

      final handledIds = <int?>[];
      await ReminderNotificationCallbacks.bindResponseHandler((response) async {
        handledIds.add(response.id);
      });

      expect(handledIds, <int?>[99]);
    },
  );

  test(
    'queues foreground response when handler is unbound and drains later',
    () async {
      await ReminderNotificationCallbacks.onForegroundResponse(
        NotificationResponse(
          notificationResponseType:
              NotificationResponseType.selectedNotificationAction,
          id: 55,
        ),
      );

      final handledIds = <int?>[];
      await ReminderNotificationCallbacks.bindResponseHandler((response) async {
        handledIds.add(response.id);
      });

      expect(handledIds, <int?>[55]);
    },
  );

  test('failed pending item stays queued for next bind retry', () async {
    await reminderNotificationTapBackground(
      NotificationResponse(
        notificationResponseType:
            NotificationResponseType.selectedNotificationAction,
        id: 77,
      ),
    );

    var firstAttempt = true;
    await ReminderNotificationCallbacks.bindResponseHandler((response) async {
      if (firstAttempt) {
        firstAttempt = false;
        throw Exception('temporary failure');
      }
    });

    final handledIds = <int?>[];
    await ReminderNotificationCallbacks.bindResponseHandler((response) async {
      handledIds.add(response.id);
    });

    expect(handledIds, <int?>[77]);
  });

  test(
    'background handler failure while bound is enqueued for retry',
    () async {
      var firstAttempt = true;
      await ReminderNotificationCallbacks.bindResponseHandler((response) async {
        if (firstAttempt) {
          firstAttempt = false;
          throw Exception('temporary failure');
        }
      });

      await reminderNotificationTapBackground(
        NotificationResponse(
          notificationResponseType:
              NotificationResponseType.selectedNotificationAction,
          id: 123,
        ),
      );

      final handledIds = <int?>[];
      await ReminderNotificationCallbacks.bindResponseHandler((response) async {
        handledIds.add(response.id);
      });

      expect(handledIds, <int?>[123]);
    },
  );
}