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

import 'package:http/http.dart' as http;

import '../core/config.dart';
import '../core/exceptions.dart';
import '../core/models.dart';
import '../utils/cache_manager.dart';
import '../utils/performance_monitor.dart';
import '../utils/string_utils.dart';
import '../utils/type_validator.dart';

/// Swagger数据解析器
/// 负责解析Swagger JSON文档并提取相关信息
class SwaggerDataParser {
  final CacheManager _cacheManager;
  final PerformanceMonitor _performanceMonitor;
  final TypeValidator _typeValidator;

  // 缓存解析结果
  SwaggerDocument? _cachedDocument;

  SwaggerDataParser()
      : _cacheManager = CacheManager(),
        _performanceMonitor = PerformanceMonitor(),
        _typeValidator = TypeValidator();

  /// 获取并解析Swagger JSON文档
  Future<SwaggerDocument> fetchAndParseSwaggerDocument() async {
    // 如果有缓存且未过期，直接返回缓存结果
    if (_cachedDocument != null) {
      return _cachedDocument!;
    }

    return _performanceMonitor.measure(
      'fetchAndParseSwaggerDocument',
      () async {
        try {
          print('🔄 正在获取Swagger JSON文档...');

          Map<String, dynamic> jsonData;

          if (SwaggerConfig.swaggerJsonUrl.startsWith('file://')) {
            // 处理本地文件
            final filePath =
                SwaggerConfig.swaggerJsonUrl.replaceFirst('file://', '');
            final file = File(filePath);
            if (await file.exists()) {
              final content = await file.readAsString();
              jsonData = json.decode(content) as Map<String, dynamic>;
            } else {
              throw SwaggerParseException(
                '本地文件不存在',
                url: SwaggerConfig.swaggerJsonUrl,
                details: '文件路径: $filePath',
              );
            }
          } else {
            // 处理远程URL
            final response = await http.get(
              Uri.parse(SwaggerConfig.swaggerJsonUrl),
              headers: SwaggerConfig.httpHeaders,
            );

            if (response.statusCode == 200) {
              jsonData = json.decode(response.body) as Map<String, dynamic>;
            } else {
              throw SwaggerParseException(
                'HTTP请求失败',
                url: SwaggerConfig.swaggerJsonUrl,
                statusCode: response.statusCode,
                details: 'HTTP响应状态码: ${response.statusCode}',
              );
            }
          }

          _cachedDocument = await parseSwaggerDocument(jsonData);
          print('✅ Swagger文档解析完成');
          return _cachedDocument!;
        } catch (e) {
          if (e is SwaggerParseException) {
            rethrow;
          }
          throw SwaggerParseException(
            '获取Swagger文档失败',
            url: SwaggerConfig.swaggerJsonUrl,
            details: e.toString(),
          );
        }
      },
    );
  }

  /// 解析Swagger JSON文档
  Future<SwaggerDocument> parseSwaggerDocument(
    Map<String, dynamic> jsonData,
  ) async {
    return _performanceMonitor.measure('parseSwaggerDocument', () async {
      // 尝试从缓存获取
      final cacheKey = 'swagger_doc_${jsonData.hashCode}';
      final cachedResult = _cacheManager.get<SwaggerDocument>(cacheKey);
      if (cachedResult != null) {
        _cachedDocument = cachedResult;
        return cachedResult;
      }

      // 解析文档基本信息
      final info = jsonData['info'] as Map<String, dynamic>? ?? {};
      final title = info['title'] as String? ?? 'API Documentation';
      final version = info['version'] as String? ?? '1.0.0';
      final description = info['description'] as String? ?? '';

      // 解析其他基本信息
      final host = jsonData['host'] as String? ?? '';
      final basePath = jsonData['basePath'] as String? ?? '/';
      final schemes = List<String>.from(jsonData['schemes'] ?? ['https']);
      final consumes = List<String>.from(jsonData['consumes'] ?? []);
      final produces = List<String>.from(jsonData['produces'] ?? []);

      // 解析tags信息 (用于获取控制器描述)
      final tagsInfo = _parseTagsInfo(jsonData);

      // 解析API路径
      final paths = _parseApiPaths(jsonData);

      // 解析API模型
      final models = _parseApiModels(jsonData);

      // 解析API控制器 (传入tags信息)
      final controllers = _parseApiControllers(paths, tagsInfo);

      final document = SwaggerDocument(
        title: title,
        version: version,
        description: description,
        host: host,
        basePath: basePath,
        schemes: schemes,
        consumes: consumes,
        produces: produces,
        paths: paths,
        models: models,
        controllers: controllers,
      );

      // 缓存结果
      _cacheManager.put(cacheKey, document);
      _cachedDocument = document;

      return document;
    });
  }

  /// 解析tags信息
  Map<String, String> _parseTagsInfo(Map<String, dynamic> jsonData) {
    final tagsInfo = <String, String>{};

    try {
      final tags = jsonData['tags'] as List<dynamic>?;
      if (tags != null) {
        for (final tag in tags) {
          if (tag is Map<String, dynamic>) {
            final name = tag['name'] as String?;
            final description = tag['description'] as String?;
            if (name != null && description != null) {
              tagsInfo[name] = description;
            }
          }
        }
      }
    } catch (e) {
      print('⚠️  解析tags信息时发生错误: $e');
    }

    return tagsInfo;
  }

  /// 解析API路径
  Map<String, ApiPath> _parseApiPaths(Map<String, dynamic> jsonData) {
    final paths = <String, ApiPath>{};
    final pathsData = jsonData['paths'] as Map<String, dynamic>?;

    if (pathsData == null) {
      throw SwaggerParseException('未发现API路径定义');
    }

    try {
      pathsData.forEach((pathKey, pathValue) {
        if (pathValue is Map<String, dynamic>) {
          pathValue.forEach((methodKey, methodValue) {
            if (methodValue is Map<String, dynamic>) {
              final method = HttpMethod.fromString(methodKey);
              final apiPath = ApiPath.fromJson(
                pathKey,
                methodKey, // 传入字符串而不是HttpMethod对象
                methodValue,
              );
              final key =
                  '${method.value.toUpperCase()}_${pathKey.replaceAll('/', '_')}';
              paths[key] = apiPath;
            }
          });
        }
      });
    } catch (e) {
      throw SwaggerParseException('解析API路径失败', details: e.toString());
    }

    return paths;
  }

  /// 解析API模型
  Map<String, ApiModel> _parseApiModels(Map<String, dynamic> jsonData) {
    final models = <String, ApiModel>{};

    // 优先解析 components/schemas (Swagger 3.0)
    final schemas = jsonData['components']?['schemas'] as Map<String, dynamic>?;
    // 如果没有 components/schemas，尝试解析 definitions (Swagger 2.0)
    final definitions = jsonData['definitions'] as Map<String, dynamic>?;

    final modelDefinitions = schemas ?? definitions;

    if (modelDefinitions == null) {
      print('ℹ️  未发现模型定义 (components/schemas 或 definitions)');
      return models;
    }

    print(
      '🔍 发现模型定义位置: ${schemas != null ? 'components/schemas' : 'definitions'}',
    );

    try {
      modelDefinitions.forEach((name, definition) {
        final model = ApiModel.fromJson(
          name,
          definition as Map<String, dynamic>,
        );
        models[name] = model;
      });
    } catch (e) {
      throw SwaggerParseException('解析API模型失败', details: e.toString());
    }

    return models;
  }

  /// 解析API控制器
  Map<String, ApiController> _parseApiControllers(
    Map<String, ApiPath> paths,
    Map<String, String> tagsInfo,
  ) {
    final controllers = <String, List<ApiPath>>{};

    try {
      // 根据tags分组API路径
      for (final apiPath in paths.values) {
        for (final tag in apiPath.tags) {
          controllers.putIfAbsent(tag, () => []).add(apiPath);
        }
      }

      // 创建控制器对象
      final result = <String, ApiController>{};
      controllers.forEach((name, pathList) {
        // 从tags信息中获取描述
        final swaggerDescription = tagsInfo[name];

        // 使用通用的描述获取方法
        final description = SwaggerConfig.getControllerDescription(
          name,
          swaggerDescription: swaggerDescription,
        );

        result[name] = ApiController(
          name: name,
          description: description,
          paths: pathList,
        );
      });

      return result;
    } catch (e) {
      throw SwaggerParseException('解析API控制器失败', details: e.toString());
    }
  }

  /// 解析属性类型
  String parsePropertyType(Map<String, dynamic> propData) {
    try {
      // 直接类型
      if (propData['type'] != null) {
        return propData['type'] as String;
      }

      // 引用类型 ($ref)
      if (propData['\$ref'] != null) {
        final ref = propData['\$ref'] as String;
        // 从 #/components/schemas/ModelName 或 #/definitions/ModelName 中提取类型名
        final parts = ref.split('/');
        if (parts.isNotEmpty) {
          return parts.last;
        }
      }

      // 数组类型
      if (propData['items'] != null) {
        final items = propData['items'] as Map<String, dynamic>;
        final itemType = parsePropertyType(items);
        return 'array<$itemType>';
      }

      // 默认类型
      return 'string';
    } catch (e) {
      throw SwaggerParseException('解析属性类型失败', details: e.toString());
    }
  }

  /// 获取Dart类型映射
  String getDartType(String swaggerType, String? format) {
    switch (swaggerType.toLowerCase()) {
      case 'string':
        switch (format?.toLowerCase()) {
          case 'date':
          case 'date-time':
            return 'DateTime';
          case 'byte':
          case 'binary':
            return 'String';
          default:
            return 'String';
        }
      case 'integer':
        switch (format?.toLowerCase()) {
          case 'int64':
            return 'int';
          case 'int32':
          default:
            return 'int';
        }
      case 'number':
        switch (format?.toLowerCase()) {
          case 'float':
          case 'double':
            return 'double';
          default:
            return 'double';
        }
      case 'boolean':
        return 'bool';
      case 'array':
        return 'List<dynamic>';
      case 'object':
        return 'Map<String, dynamic>';
      case 'file':
        return 'String';
      default:
        // 检查是否为数组类型
        if (swaggerType.startsWith('array<') && swaggerType.endsWith('>')) {
          final itemType = swaggerType.substring(6, swaggerType.length - 1);
          final dartItemType = getDartType(itemType, null);
          return 'List<$dartItemType>';
        }

        // 默认为自定义类型
        return StringUtils.generateClassName(swaggerType);
    }
  }

  /// 清除缓存
  void clearCache() {
    _cachedDocument = null;
    _cacheManager.clear();
  }

  /// 获取文档统计信息
  Map<String, dynamic> getDocumentStats() {
    if (_cachedDocument == null) {
      return {};
    }

    final doc = _cachedDocument!;

    // 统计HTTP方法
    final methodStats = <String, int>{};
    for (final path in doc.paths.values) {
      final method = path.method.value;
      methodStats[method] = (methodStats[method] ?? 0) + 1;
    }

    // 统计模型类型
    final modelStats = <String, int>{};
    for (final model in doc.models.values) {
      if (model.isEnum) {
        modelStats['enum'] = (modelStats['enum'] ?? 0) + 1;
      } else {
        modelStats['class'] = (modelStats['class'] ?? 0) + 1;
      }
    }

    return {
      'title': doc.title,
      'version': doc.version,
      'paths': doc.paths.length,
      'models': doc.models.length,
      'controllers': doc.controllers.length,
      'methods': methodStats,
      'modelTypes': modelStats,
    };
  }
}