import 'package:flutter_test/flutter_test.dart';
import 'package:url_launcher_platform_interface/link.dart';
import 'package:url_launcher_platform_interface/url_launcher_platform_interface.dart';

import 'package:emergency/services/dialer_service.dart';

/// Fake-Implementierung der `url_launcher`-Plattformschnittstelle.
///
/// Vermeidet Mocking auf `MethodChannel`-Ebene: `url_launcher` erlaubt es,
/// [UrlLauncherPlatform.instance] durch eine eigene Implementierung zu
/// ersetzen – das ist der offiziell vorgesehene Weg, das Package in reinen
/// Unit-Tests ohne echte Plattform-Kanäle zu testen.
class _FakeUrlLauncherPlatform extends UrlLauncherPlatform {
  _FakeUrlLauncherPlatform({required this.canLaunchResult});

  final bool canLaunchResult;

  String? launchedUrl;
  int launchCallCount = 0;

  @override
  LinkDelegate? get linkDelegate => null;

  @override
  Future<bool> canLaunch(String url) async => canLaunchResult;

  @override
  Future<bool> launchUrl(String url, LaunchOptions options) async {
    launchCallCount++;
    launchedUrl = url;
    return true;
  }
}

void main() {
  TestWidgetsFlutterBinding.ensureInitialized();

  group('DialerService', () {
    const dialerService = DialerService();

    test('call() öffnet den Wähler mit tel:-URI und liefert true, wenn canLaunch true ist', () async {
      final fakePlatform = _FakeUrlLauncherPlatform(canLaunchResult: true);
      UrlLauncherPlatform.instance = fakePlatform;

      final result = await dialerService.call('112');

      expect(result, isTrue);
      expect(fakePlatform.launchCallCount, 1);
      expect(fakePlatform.launchedUrl, 'tel:112');
    });

    test('call() liefert false ohne launch(), wenn canLaunch false ist', () async {
      final fakePlatform = _FakeUrlLauncherPlatform(canLaunchResult: false);
      UrlLauncherPlatform.instance = fakePlatform;

      final result = await dialerService.call('911');

      expect(result, isFalse);
      expect(fakePlatform.launchCallCount, 0);
    });
  });
}