import 'dart:convert';
import 'dart:io';

import 'package:path/path.dart' as p;
import 'package:swagger_generator_flutter/commands/generate_command.dart';
import 'package:swagger_generator_flutter/utils/path_resolver.dart';
import 'package:test/test.dart';

void main() {
  late Directory originalCwd;
  late Directory tempDir;

  setUp(() async {
    originalCwd = Directory.current;
    tempDir = await Directory(
      p.join(
        originalCwd.path,
        'test',
        'tmp',
        'generate_command_${DateTime.now().microsecondsSinceEpoch}',
      ),
    ).create(recursive: true);
    Directory.current = tempDir;
    PathResolver.clearCache();
  });

  tearDown(() async {
    PathResolver.clearCache();
    Directory.current = originalCwd;
    if (tempDir.existsSync()) {
      await tempDir.delete(recursive: true);
    }
  });

  test('按版本生成 API 与模型文件', () async {
    await _writeJson(
      'swagger_v1.json',
      _buildSwaggerDoc(
        title: 'Test API V1',
        version: '1.0.0',
        specs: [
          const _PathSpec(
            path: '/api/v1/users',
            tag: 'Users',
            schemaName: 'User',
            operationId: 'getUsers',
          ),
        ],
      ),
    );

    await _writeJson(
      'swagger_v2.json',
      _buildSwaggerDoc(
        title: 'Test API V2',
        version: '2.0.0',
        specs: [
          const _PathSpec(
            path: '/api/v2/admins',
            tag: 'Admins',
            schemaName: 'Admin',
            operationId: 'getAdmins',
          ),
        ],
      ),
    );

    await _writeConfig(
      swaggerFiles: ['swagger_v1.json', 'swagger_v2.json'],
      apiClientClassName: 'MultiVersionApiClient',
      apiClientFileName: 'multi_version_client',
    );

    final exitCode = await GenerateCommand().execute([]);
    expect(exitCode, equals(0));

    final outputDir = Directory(p.join(tempDir.path, 'out'));
    expect(outputDir.existsSync(), isTrue);

    final apiV1Dir = Directory(p.join(outputDir.path, 'api', 'v1'));
    final apiV2Dir = Directory(p.join(outputDir.path, 'api', 'v2'));
    expect(apiV1Dir.existsSync(), isTrue);
    expect(apiV2Dir.existsSync(), isTrue);

    expect(
      _dartFiles(apiV1Dir).isNotEmpty,
      isTrue,
      reason: 'v1 版本应至少生成一个 API 文件',
    );
    expect(
      _dartFiles(apiV2Dir).isNotEmpty,
      isTrue,
      reason: 'v2 版本应至少生成一个 API 文件',
    );

    final apiClient =
        File(p.join(outputDir.path, 'api', 'multi_version_client.dart'));
    expect(apiClient.existsSync(), isTrue);

    final summary = File(p.join(outputDir.path, 'SUMMARY.md'));
    expect(summary.existsSync(), isTrue);
    final summaryContent = summary.readAsStringSync();
    expect(summaryContent, contains('API标题'));
    expect(summaryContent, contains('API版本'));

    final modelsDir = Directory(p.join(outputDir.path, 'models', 'result'));
    expect(modelsDir.existsSync(), isTrue);
    final modelFiles = _dartFiles(modelsDir);
    expect(
      modelFiles.length,
      greaterThanOrEqualTo(2),
      reason: '示例应生成 User 与 Admin 模型文件',
    );
  });

  test('支持命令行 tag 过滤', () async {
    await _writeJson(
      'swagger_filtered.json',
      _buildSwaggerDoc(
        title: 'Filtered API',
        version: '1.0.0',
        specs: const [
          _PathSpec(
            path: '/api/v1/users',
            tag: 'Users',
            schemaName: 'User',
            operationId: 'getUsers',
          ),
          _PathSpec(
            path: '/api/v1/internal',
            tag: 'Internal',
            schemaName: 'InternalModel',
            operationId: 'getInternal',
          ),
        ],
      ),
    );

    await _writeConfig(
      swaggerFiles: ['swagger_filtered.json'],
      apiClientClassName: 'FilteredApiClient',
      apiClientFileName: 'filtered_api_client',
    );

    final exitCode = await GenerateCommand().execute([
      '--api',
      '--models',
      '--included-tags=Users',
      '--excluded-tags=Internal',
    ]);
    expect(exitCode, equals(0));

    final apiDir = Directory(p.join(tempDir.path, 'out', 'api', 'v1'));
    expect(apiDir.existsSync(), isTrue);
    final apiFiles = _dartFiles(apiDir);
    expect(apiFiles.any((file) => file.contains('internal')), isFalse);
    expect(apiFiles.any((file) => file.contains('user')), isTrue);

    final resultDir =
        Directory(p.join(tempDir.path, 'out', 'models', 'result'));
    expect(resultDir.existsSync(), isTrue);
    final modelNames = _dartFiles(resultDir).map(p.basename).toList();
    expect(modelNames.any((name) => name.contains('internal')), isFalse);
    expect(modelNames.any((name) => name.contains('user')), isTrue);
  });
}

Future<void> _writeJson(String name, Map<String, dynamic> data) async {
  final file = File(p.join(Directory.current.path, name));
  await file.writeAsString(jsonEncode(data));
}

Future<void> _writeConfig({
  required List<String> swaggerFiles,
  required String apiClientClassName,
  required String apiClientFileName,
}) async {
  final buffer = StringBuffer()
    ..writeln('generator:')
    ..writeln('  name: "test-generator"')
    ..writeln('  version: "1.0.0"')
    ..writeln('  author: "codex"')
    ..writeln(
      '  copyright: "Copyright (C) 2025 '
      'Swagger Generator Flutter. All rights reserved."',
    )
    ..writeln('input:')
    ..writeln('  swagger_urls:');

  for (final file in swaggerFiles) {
    buffer.writeln('    - "./$file"');
  }

  buffer
    ..writeln('output:')
    ..writeln('  base_dir: "./out"')
    ..writeln('  api_dir: "./out/api"')
    ..writeln('  models_dir: "./out/models"')
    ..writeln('  split_by_tags: true')
    ..writeln('generation:')
    ..writeln('  api:')
    ..writeln('    client:')
    ..writeln('      class_name: "$apiClientClassName"')
    ..writeln('      file_name: "$apiClientFileName"')
    ..writeln('    version_extraction:')
    ..writeln(r'      pattern: "/api/v(\\d+)/"')
    ..writeln('      default_version: "v1"')
    ..writeln('  models:')
    ..writeln('    enabled: true');

  await File(p.join(Directory.current.path, 'generator_config.yaml'))
      .writeAsString(buffer.toString());
}

Map<String, dynamic> _buildSwaggerDoc({
  required String title,
  required String version,
  required List<_PathSpec> specs,
}) {
  final tagDescriptions = <String, String>{};
  final schemas = <String, Map<String, dynamic>>{};
  final paths = <String, Map<String, dynamic>>{};

  for (final spec in specs) {
    tagDescriptions.putIfAbsent(spec.tag, () => '${spec.tag} APIs');
    schemas[spec.schemaName] = _schemaDefinition(spec.schemaName);
    final operations = paths.putIfAbsent(spec.path, () => <String, dynamic>{});
    operations['get'] = _operationFor(spec);
  }

  return {
    'openapi': '3.0.0',
    'info': {
      'title': title,
      'version': version,
      'description': '$title description',
    },
    'tags': tagDescriptions.entries
        .map(
          (entry) => {
            'name': entry.key,
            'description': entry.value,
          },
        )
        .toList(),
    'paths': paths.map(MapEntry.new),
    'components': {
      'schemas': schemas,
    },
  };
}

Map<String, dynamic> _operationFor(_PathSpec spec) {
  return {
    'summary': '${spec.tag} summary',
    'description': '${spec.tag} description',
    'operationId': spec.operationId,
    'tags': [spec.tag],
    'responses': {
      '200': {
        'description': 'OK',
        'content': {
          'application/json': {
            'schema': {
              'type': 'array',
              'items': {r'$ref': '#/components/schemas/${spec.schemaName}'},
            },
          },
        },
      },
    },
  };
}

Map<String, dynamic> _schemaDefinition(String name) {
  return {
    'type': 'object',
    'properties': {
      'id': {'type': 'integer', 'format': 'int64'},
      'name': {'type': 'string'},
    },
    'required': ['id'],
    'description': '$name definition',
  };
}

Iterable<String> _dartFiles(Directory directory) {
  if (!directory.existsSync()) {
    return const Iterable<String>.empty();
  }
  return directory
      .listSync()
      .whereType<File>()
      .map((file) => file.path)
      .where((path) => path.endsWith('.dart'));
}

class _PathSpec {
  const _PathSpec({
    required this.path,
    required this.tag,
    required this.schemaName,
    required this.operationId,
  });

  final String path;
  final String tag;
  final String schemaName;
  final String operationId;
}