import 'package:flutter/material.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:provider/provider.dart';
import 'package:shared_preferences/shared_preferences.dart';

import 'package:fuel_tax_tracker/screens/data_settings_screen.dart';
import 'package:fuel_tax_tracker/screens/faq_screen.dart';
import 'package:fuel_tax_tracker/services/app_state.dart';
import 'package:fuel_tax_tracker/services/cloud/cloud_storage_provider.dart';
import 'package:fuel_tax_tracker/services/cloud_sync_service.dart';
import 'package:fuel_tax_tracker/services/database_service.dart';
import 'package:fuel_tax_tracker/widgets/backup_reminder.dart';

/// Covers the "your data isn't backed up" nudge shown after saving a fuel
/// entry with no cloud backup configured — see
/// `ConfirmFuelEntryScreen._save`. The dialog and the spotlight it can lead
/// to (`showBackupReminderDialog`/`openCloudBackupSetup`) are tested here
/// as standalone functions rather than through a full save, matching
/// settings_purge_test.dart's convention of not exercising actions that
/// need an initialized database.
void main() {
  setUp(() {
    SharedPreferences.setMockInitialValues({});
  });

  group('showBackupReminderDialog', () {
    Future<bool?> openDialog(WidgetTester tester) async {
      bool? result;
      await tester.pumpWidget(
        MaterialApp(
          home: Builder(
            builder: (context) => ElevatedButton(
              onPressed: () async => result = await showBackupReminderDialog(context),
              child: const Text('open'),
            ),
          ),
        ),
      );
      await tester.tap(find.text('open'));
      await tester.pumpAndSettle();
      return result;
    }

    testWidgets('shows the warning with both actions', (tester) async {
      await openDialog(tester);

      expect(find.text("Your Data Isn't Backed Up"), findsOneWidget);
      expect(find.text('Learn More'), findsOneWidget);
      expect(find.text('Not Now'), findsOneWidget);
      expect(find.text('Set Up Backup'), findsOneWidget);
    });

    testWidgets('Learn More resolves false, closes the dialog, and opens the FAQ to the '
        'backup question', (tester) async {
      bool? result;
      await tester.pumpWidget(
        MaterialApp(
          home: Builder(
            builder: (context) => ElevatedButton(
              onPressed: () async => result = await showBackupReminderDialog(context),
              child: const Text('open'),
            ),
          ),
        ),
      );
      await tester.tap(find.text('open'));
      await tester.pumpAndSettle();

      await tester.tap(find.text('Learn More'));
      await tester.pumpAndSettle();

      expect(result, isFalse);
      expect(find.text("Your Data Isn't Backed Up"), findsNothing, reason: 'dialog closed');
      expect(find.byType(FaqScreen), findsOneWidget);

      await tester.scrollUntilVisible(find.text('Is my data backed up?'), 300,
          scrollable: find.byType(Scrollable));
      expect(find.textContaining('Not by default'), findsOneWidget,
          reason: 'backup question starts expanded');
    });

    testWidgets('Not Now resolves false and closes the dialog', (tester) async {
      bool? result;
      await tester.pumpWidget(
        MaterialApp(
          home: Builder(
            builder: (context) => ElevatedButton(
              onPressed: () async => result = await showBackupReminderDialog(context),
              child: const Text('open'),
            ),
          ),
        ),
      );
      await tester.tap(find.text('open'));
      await tester.pumpAndSettle();

      await tester.tap(find.text('Not Now'));
      await tester.pumpAndSettle();

      expect(result, isFalse);
      expect(find.text("Your Data Isn't Backed Up"), findsNothing);
    });

    testWidgets('Set Up Backup resolves true and closes the dialog', (tester) async {
      bool? result;
      await tester.pumpWidget(
        MaterialApp(
          home: Builder(
            builder: (context) => ElevatedButton(
              onPressed: () async => result = await showBackupReminderDialog(context),
              child: const Text('open'),
            ),
          ),
        ),
      );
      await tester.tap(find.text('open'));
      await tester.pumpAndSettle();

      await tester.tap(find.text('Set Up Backup'));
      await tester.pumpAndSettle();

      expect(result, isTrue);
      expect(find.text("Your Data Isn't Backed Up"), findsNothing);
    });
  });

  group('openCloudBackupSetup', () {
    testWidgets('pushes Settings > Data with the cloud storage card spotlighted',
        (tester) async {
      final appState = AppState()..isLoading = false;

      await tester.pumpWidget(
        ChangeNotifierProvider.value(
          value: appState,
          child: MaterialApp(
            home: Builder(
              builder: (context) => ElevatedButton(
                onPressed: () => openCloudBackupSetup(context),
                child: const Text('open'),
              ),
            ),
          ),
        ),
      );

      await tester.tap(find.text('open'));
      await tester.pumpAndSettle();

      expect(find.byType(DataSettingsScreen), findsOneWidget);
      expect(find.text('Back Up to the Cloud'), findsOneWidget);
      expect(find.widgetWithText(FilledButton, 'Got It'), findsOneWidget);
    });

    testWidgets('dismissing the spotlight leaves the Data screen up', (tester) async {
      final appState = AppState()..isLoading = false;

      await tester.pumpWidget(
        ChangeNotifierProvider.value(
          value: appState,
          child: MaterialApp(
            home: Builder(
              builder: (context) => ElevatedButton(
                onPressed: () => openCloudBackupSetup(context),
                child: const Text('open'),
              ),
            ),
          ),
        ),
      );
      await tester.tap(find.text('open'));
      await tester.pumpAndSettle();

      await tester.tap(find.widgetWithText(FilledButton, 'Got It'));
      await tester.pumpAndSettle();

      expect(find.text('Back Up to the Cloud'), findsNothing, reason: 'spotlight dismissed');
      expect(find.byType(DataSettingsScreen), findsOneWidget, reason: 'still on the Data screen');
    });
  });

  group('AppState.hasCloudBackupConfigured', () {
    test('false with no cloud provider connected at all', () {
      final appState = AppState();
      expect(appState.hasCloudBackupConfigured, isFalse);
    });

    test('false when a provider is connected but no folder has been chosen', () {
      final appState = AppState()
        ..cloudSync = CloudSyncService(provider: _FakeProvider(), databaseService: DatabaseService());

      expect(appState.hasCloudBackupConfigured, isFalse);
    });

    test('true once a backup folder has been configured', () {
      final appState = AppState()
        ..cloudSync =
            (CloudSyncService(provider: _FakeProvider(), databaseService: DatabaseService())
              ..configure('folder-id'));

      expect(appState.hasCloudBackupConfigured, isTrue);
    });
  });
}

class _FakeProvider implements CloudStorageProvider {
  @override
  CloudProviderId get id => CloudProviderId.googleDrive;

  @override
  String get displayName => 'Fake Provider';

  @override
  bool get isSignedIn => true;

  @override
  String? get accountLabel => 'tester@example.com';

  @override
  Future<bool> attemptSilentSignIn() async => true;

  @override
  Future<String> signIn() async => accountLabel!;

  @override
  Future<void> signOut() async {}

  @override
  CloudStorageSession beginSession() => throw UnimplementedError();
}