import 'dart:io';
import 'dart:async';
import 'package:flutter/material.dart';
import 'package:flutter_test/flutter_test.dart';
// ignore: depend_on_referenced_packages
import 'package:image_picker_platform_interface/image_picker_platform_interface.dart';
import 'package:material_symbols_icons/symbols.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:ikar/core/media/gallery_source.dart';
import 'package:ikar/frontend/widgets/attachment/attachment_sheet.dart';
import 'package:ikar/l10n/app_localizations.dart';

class FakeGallery implements GallerySource {
  FakeGallery({
    this.permission = GalleryPermission.granted,
    this.fail = false,
    this.count = 8,
    this.hang = false,
  });
  GalleryPermission permission;
  int requests = 0;
  int settingsOpened = 0;
  final bool fail;
  final int count;
  final bool hang;
  @override
  Future<GalleryPermission> ensurePermission() async {
    requests++;
    return permission;
  }

  @override
  Future<GalleryPermission> currentPermission() async => permission;
  @override
  Future<GalleryPage> load({int offset = 0, int limit = 120}) async {
    if (hang) return Completer<GalleryPage>().future;
    if (fail) throw StateError('gallery unavailable');
    return GalleryPage(
      items: List.generate(
        count,
        (i) => GalleryItem.fromFile(File('missing-$i.jpg')),
      ),
      hasMore: false,
    );
  }

  @override
  Future<void> openSettings() async {
    settingsOpened++;
  }

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

void main() {
  setUp(
    () => SharedPreferences.setMockInitialValues({
      'attachment_gallery_access_explained_v1': true,
    }),
  );
  Future<void> openSheet(WidgetTester tester, FakeGallery source) async {
    await tester.pumpWidget(
      MaterialApp(
        locale: const Locale('ru'),
        localizationsDelegates: AppLocalizations.localizationsDelegates,
        supportedLocales: AppLocalizations.supportedLocales,
        home: Scaffold(body: AttachmentSheet(gallerySource: source)),
      ),
    );
    await tester.pump();
    await tester.pump(const Duration(milliseconds: 300));
  }

  for (final allow in [true, false]) {
    testWidgets('first gallery opening explains access, allow=$allow', (
      tester,
    ) async {
      SharedPreferences.setMockInitialValues({});
      final source = FakeGallery(permission: GalleryPermission.denied);
      await openSheet(tester, source);
      await tester.pump(const Duration(milliseconds: 300));
      expect(find.byType(AlertDialog), findsOneWidget);
      expect(source.requests, 0);
      final dialog = find.byType(AlertDialog);
      await tester.tap(
        find.descendant(
          of: dialog,
          matching: find.byType(allow ? FilledButton : TextButton),
        ),
      );
      await tester.pumpAndSettle();
      expect(source.requests, allow ? 1 : 0);
      expect(find.byType(AlertDialog), findsNothing);
      expect(
        (await SharedPreferences.getInstance()).getBool(
          'attachment_gallery_access_explained_v1',
        ),
        isTrue,
      );
    });
  }
  testWidgets('full access skips introduction and permission request', (
    tester,
  ) async {
    SharedPreferences.setMockInitialValues({});
    final source = FakeGallery();
    await openSheet(tester, source);
    expect(find.byType(AlertDialog), findsNothing);
    expect(source.requests, 0);
  });
  testWidgets(
    'empty limited gallery retains settings action and refreshes on return',
    (tester) async {
      final source = FakeGallery(
        permission: GalleryPermission.limited,
        count: 0,
      );
      await openSheet(tester, source);
      expect(
        find.textContaining('Доступны только выбранные фото'),
        findsOneWidget,
      );
      await tester.tap(find.text('Настройки'));
      expect(source.settingsOpened, 1);
      source.permission = GalleryPermission.granted;
      tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.inactive);
      tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.resumed);
      await tester.pumpAndSettle();
      expect(
        find.textContaining('Доступны только выбранные фото'),
        findsNothing,
      );
    },
  );
  testWidgets(
    'system picker sends chosen photos when gallery access is denied',
    (tester) async {
      final original = ImagePickerPlatform.instance;
      final picker = FakePicker()..files = [XFile('one.jpg'), XFile('two.jpg')];
      ImagePickerPlatform.instance = picker;
      addTearDown(() => ImagePickerPlatform.instance = original);
      List<PickedPhoto>? sent;
      await tester.pumpWidget(
        MaterialApp(
          locale: const Locale('ru'),
          localizationsDelegates: AppLocalizations.localizationsDelegates,
          supportedLocales: AppLocalizations.supportedLocales,
          home: Scaffold(
            body: Builder(
              builder: (context) => TextButton(
                onPressed: () => showModalBottomSheet<void>(
                  context: context,
                  isScrollControlled: true,
                  builder: (_) => AttachmentSheet(
                    gallerySource: FakeGallery(
                      permission: GalleryPermission.denied,
                    ),
                    onSend: (photos, caption) => sent = photos,
                  ),
                ),
                child: const Text('open'),
              ),
            ),
          ),
        ),
      );
      await tester.tap(find.text('open'));
      await tester.pumpAndSettle();
      await tester.tap(find.widgetWithText(TextButton, 'Камера'));
      await tester.pumpAndSettle();
      expect(picker.source, ImageSource.camera);
      expect(find.byType(AttachmentSheet), findsOneWidget);
      await tester.tap(find.widgetWithText(TextButton, 'Галерея'));
      await tester.pumpAndSettle();
      expect(tester.takeException(), isNull);
      await tester.tap(find.byIcon(Symbols.send));
      await tester.pumpAndSettle();
      expect(sent?.map((photo) => photo.item.localFile?.path), [
        'one.jpg',
        'two.jpg',
      ]);
      expect(find.byType(AttachmentSheet), findsNothing);
    },
  );
  for (final scenario in ['photos', 'empty', 'denied', 'error', 'timeout']) {
    testWidgets(
      'attachment gallery $scenario keeps camera visible and finite',
      (tester) async {
        await tester.binding.setSurfaceSize(const Size(400, 850));
        addTearDown(() => tester.binding.setSurfaceSize(null));
        await tester.pumpWidget(
          MaterialApp(
            locale: const Locale('ru'),
            localizationsDelegates: AppLocalizations.localizationsDelegates,
            supportedLocales: AppLocalizations.supportedLocales,
            home: Scaffold(
              body: AttachmentSheet(
                gallerySource: FakeGallery(
                  permission: scenario == 'denied'
                      ? GalleryPermission.denied
                      : GalleryPermission.granted,
                  fail: scenario == 'error',
                  hang: scenario == 'timeout',
                  count: scenario == 'empty' ? 0 : 8,
                ),
              ),
            ),
          ),
        );
        await tester.pump();
        await tester.pump(const Duration(milliseconds: 200));
        if (scenario == 'timeout') {
          expect(find.widgetWithText(TextButton, 'Камера'), findsOneWidget);
          await tester.pump(const Duration(seconds: 21));
          await tester.pump();
          expect(find.text('Не удалось загрузить галерею'), findsOneWidget);
        }
        expect(tester.takeException(), isNull);
        expect(find.widgetWithText(TextButton, 'Камера'), findsOneWidget);
        expect(find.widgetWithText(TextButton, 'Галерея'), findsOneWidget);
        expect(find.byType(CustomScrollView), findsOneWidget);
      },
    );
  }
}

class FakePicker extends ImagePickerPlatform {
  List<XFile> files = [];
  ImageSource? source;
  @override
  Future<List<XFile>> getMedia({required MediaOptions options}) async => files;
  @override
  Future<XFile?> getImageFromSource({
    required ImageSource source,
    ImagePickerOptions options = const ImagePickerOptions(),
  }) async {
    this.source = source;
    return null;
  }
}