import 'dart:io';

import 'package:flutter/services.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:spotiflac_android/services/platform_bridge.dart';

void main() {
  TestWidgetsFlutterBinding.ensureInitialized();
  const backend = MethodChannel('com.zarz.spotiflac/backend');
  const paths = MethodChannel('plugins.flutter.io/path_provider');
  final messenger =
      TestDefaultBinaryMessengerBinding.instance.defaultBinaryMessenger;
  late Directory root;

  setUp(() async {
    root = await Directory.systemTemp.createTemp('library-full-scan-');
    messenger.setMockMethodCallHandler(paths, (_) async => root.path);
  });
  tearDown(() async {
    messenger.setMockMethodCallHandler(backend, null);
    messenger.setMockMethodCallHandler(paths, null);
    await root.delete(recursive: true);
  });

  for (final saf in [false, true]) {
    Future<LibraryScanNDJSONFile> scan({
      bool force = false,
      bool Function()? isCancelled,
    }) => saf
        ? PlatformBridge.scanSafTreeToNDJSONFile(
            'content://library/tree/music',
            forceFullScan: force,
            isCancelled: isCancelled,
          )
        : PlatformBridge.scanLibraryFolderToNDJSONFile(
            '/music',
            forceFullScan: force,
            isCancelled: isCancelled,
          );

    test('forced scan resets checkpoints and cover paths (SAF=$saf)', () async {
      final oldCovers = await Directory('${root.path}/library_covers').create();
      final oldCover = await File(
        '${oldCovers.path}/cover_same-key.jpg',
      ).writeAsBytes([1]);
      final unrelated = await File(
        '${root.path}/library_scan_other.ndjson.state',
      ).writeAsString('other source');
      final coverDirectories = <String>[];
      final resumed = <bool>[];
      messenger.setMockMethodCallHandler(backend, (call) async {
        final args = call.arguments as Map;
        if (call.method == 'setLibraryCoverCacheDir') {
          final directory = args['cache_dir'] as String;
          expect(await Directory(directory).exists(), isTrue);
          expect(await File('$directory/cover_same-key.jpg').exists(), isFalse);
          coverDirectories.add(directory);
          return null;
        }
        expect(
          call.method,
          saf ? 'scanSafTreeToNDJSONFile' : 'scanLibraryFolderToNDJSONFile',
        );
        final output = File(args['output_path'] as String);
        final checkpoint = File('${output.path}.state');
        final hasCheckpoint = await checkpoint.exists();
        expect(await output.exists(), hasCheckpoint);
        resumed.add(hasCheckpoint);
        await output.writeAsString('{"id":"track"}\n');
        await checkpoint.writeAsString('track\t123\n');
        return {'path': output.path, 'count': 1};
      });

      final first = await scan();
      final resumedScan = await scan();
      expect(resumedScan.file.path, first.file.path);
      expect(coverDirectories, isEmpty);
      final forced = await scan(force: true);
      expect(await forced.rows().toList(), [
        {'id': 'track'},
      ]);
      await scan(force: true);
      expect(resumed, [false, true, false, false]);
      expect(coverDirectories.toSet(), hasLength(2));
      expect(await oldCover.readAsBytes(), [1]);
      expect(await unrelated.readAsString(), 'other source');

      await forced.delete();
      expect(await forced.file.exists(), isFalse);
      expect(await File('${forced.file.path}.state').exists(), isFalse);
    });

    test(
      'cancel before forced scan preserves resumable output (SAF=$saf)',
      () async {
        var calls = 0;
        messenger.setMockMethodCallHandler(backend, (call) async {
          calls++;
          final output = File((call.arguments as Map)['output_path'] as String);
          await output.writeAsString('{"id":"old"}\n');
          await File('${output.path}.state').writeAsString('old\t123\n');
          return {'path': output.path, 'count': 1};
        });
        final previous = await scan();
        await expectLater(
          scan(force: true, isCancelled: () => true),
          throwsStateError,
        );
        expect(calls, 1);
        expect(await previous.file.readAsString(), '{"id":"old"}\n');
        expect(
          await File('${previous.file.path}.state').readAsString(),
          'old\t123\n',
        );
      },
    );
  }

  test('cache setup failure stops forced scan before native reads', () async {
    final calls = <String>[];
    messenger.setMockMethodCallHandler(backend, (call) async {
      calls.add(call.method);
      throw PlatformException(code: 'cache-unavailable');
    });
    await expectLater(
      PlatformBridge.scanSafTreeToNDJSONFile(
        'content://library/tree/music',
        forceFullScan: true,
      ),
      throwsA(isA<PlatformException>()),
    );
    expect(calls, ['setLibraryCoverCacheDir']);
  });
}