import APIException from "@/lib/exceptions/APIException.ts";
import EX from "@/api/consts/exceptions.ts";
import logger from "@/lib/logger.ts";

/**
 * 即梦API错误响应接口
 */
export interface JimengErrorResponse {
  ret: string;
  errmsg: string;
  data?: any;
  historyId?: string;
}

/**
 * 错误处理选项
 */
export interface ErrorHandlerOptions {
  context?: string;
  historyId?: string;
  retryCount?: number;
  maxRetries?: number;
  operation?: string;
}

/**
 * 统一的即梦API错误处理器
 */
export class JimengErrorHandler {
  
  /**
   * 处理即梦API响应错误
   */
  static handleApiResponse(
    response: JimengErrorResponse, 
    options: ErrorHandlerOptions = {}
  ): never {
    const { ret, errmsg, historyId } = response;
    const { context = '即梦API请求', operation = '操作' } = options;
    
    logger.error(`${context}失败: ret=${ret}, errmsg=${errmsg}${historyId ? `, historyId=${historyId}` : ''}`);
    
    // 根据错误码分类处理
    switch (ret) {
      case '1015':
        throw new APIException(EX.API_TOKEN_EXPIRES, `[登录失效]: ${errmsg}。请重新获取refresh_token并更新配置`);
      
      case '5000':
        throw new APIException(EX.API_IMAGE_GENERATION_INSUFFICIENT_POINTS, 
          `[积分不足]: ${errmsg}。建议：1)尝试使用1024x1024分辨率，2)检查是否需要购买积分，3)确认账户状态正常`);
      
      case '4001':
        throw new APIException(EX.API_CONTENT_FILTERED, `[内容违规]: ${errmsg}`);
      
      case '4002':
        throw new APIException(EX.API_REQUEST_PARAMS_INVALID, `[参数错误]: ${errmsg}`);
      
      case '5001':
        throw new APIException(EX.API_IMAGE_GENERATION_FAILED, `[生成失败]: ${errmsg}`);
      
      case '5002':
        throw new APIException(EX.API_VIDEO_GENERATION_FAILED, `[视频生成失败]: ${errmsg}`);
      
      default:
        throw new APIException(EX.API_REQUEST_FAILED, `[${operation}失败]: ${errmsg} (错误码: ${ret})`);
    }
  }
  
  /**
   * 处理网络请求错误
   */
  static handleNetworkError(
    error: any, 
    options: ErrorHandlerOptions = {}
  ): never {
    const { context = '网络请求', retryCount = 0, maxRetries = 3 } = options;
    
    logger.error(`${context}网络错误 (尝试 ${retryCount + 1}/${maxRetries + 1}): ${error.message}`);
    
    if (error.code === 'ECONNABORTED') {
      throw new APIException(EX.API_REQUEST_FAILED, `[请求超时]: ${context}超时，请稍后重试`);
    }
    
    if (error.code === 'ENOTFOUND') {
      throw new APIException(EX.API_REQUEST_FAILED, `[网络错误]: 无法连接到即梦服务器，请检查网络连接`);
    }
    
    if (error.response?.status >= 500) {
      throw new APIException(EX.API_REQUEST_FAILED, `[服务器错误]: 即梦服务器暂时不可用 (${error.response.status})`);
    }
    
    if (error.response?.status === 429) {
      throw new APIException(EX.API_REQUEST_FAILED, `[请求频率限制]: 请求过于频繁，请稍后重试`);
    }
    
    throw new APIException(EX.API_REQUEST_FAILED, `[${context}失败]: ${error.message}`);
  }

  /**
   * 处理轮询超时错误
   * @returns 如果有部分结果，返回 void 而不抛出异常
   */
  static handlePollingTimeout(
    pollCount: number,
    maxPollCount: number,
    elapsedTime: number,
    status: number,
    itemCount: number,
    historyId?: string
  ): void {
    const message = `轮询超时: 已轮询 ${pollCount} 次，耗时 ${elapsedTime} 秒，最终状态: ${status}，图片数量: ${itemCount}`;
    logger.warn(message + (historyId ? `，历史ID: ${historyId}` : ''));

    if (itemCount === 0) {
      throw new APIException(EX.API_IMAGE_GENERATION_FAILED,
        `生成超时且无结果，状态码: ${status}${historyId ? `，历史ID: ${historyId}` : ''}`);
    }

    // 如果有部分结果，不抛出异常，让调用者处理
    logger.info(`轮询超时但已获得 ${itemCount} 张图片，将返回现有结果`);
  }
  
  /**
   * 处理生成失败错误
   * @param itemCount 已生成的结果数量，如果 > 0 则不抛出异常
   * @returns 如果有部分结果，返回 false 表示不应抛出异常
   */
  static handleGenerationFailure(
    status: number,
    failCode: string | undefined,
    historyId?: string,
    type: 'image' | 'video' = 'image',
    itemCount: number = 0
  ): boolean {
    const typeText = type === 'image' ? '图像' : '视频';
    const message = `${typeText}生成最终失败: status=${status}, failCode=${failCode}${historyId ? `, historyId=${historyId}` : ''}, 已生成数量=${itemCount}`;

    // 如果有部分结果，只记录警告，不抛出异常
    if (itemCount > 0) {
      logger.warn(message);
      logger.info(`${typeText}生成部分失败，但已获得 ${itemCount} 个结果，将返回现有结果`);
      return false; // 不抛出异常
    }

    // 没有任何结果时，记录错误并抛出异常
    logger.error(message);
    const exception = type === 'image' ? EX.API_IMAGE_GENERATION_FAILED : EX.API_VIDEO_GENERATION_FAILED;
    throw new APIException(exception, `${typeText}生成失败，状态码: ${status}${failCode ? `，错误码: ${failCode}` : ''}`);
  }
  
  /**
   * 包装重试逻辑的错误处理
   */
  static async withRetry<T>(
    operation: () => Promise<T>,
    options: ErrorHandlerOptions & { maxRetries?: number; retryDelay?: number } = {}
  ): Promise<T> {
    const { 
      maxRetries = 3, 
      retryDelay = 5000, 
      context = '操作',
      operation: operationName = '请求'
    } = options;
    
    let lastError: any;
    
    for (let attempt = 0; attempt <= maxRetries; attempt++) {
      try {
        return await operation();
      } catch (error) {
        lastError = error;
        
        // 如果是APIException，直接抛出，不重试
        if (error instanceof APIException) {
          throw error;
        }
        
        if (attempt < maxRetries) {
          logger.warn(`${context}失败 (尝试 ${attempt + 1}/${maxRetries + 1}): ${error.message}`);
          logger.info(`${retryDelay / 1000}秒后重试...`);
          await new Promise(resolve => setTimeout(resolve, retryDelay));
        }
      }
    }
    
    // 所有重试都失败了
    this.handleNetworkError(lastError, { 
      context, 
      retryCount: maxRetries, 
      maxRetries,
      operation: operationName
    });
  }
}

/**
 * 便捷的错误处理函数
 */
export const handleJimengError = JimengErrorHandler.handleApiResponse;
export const handleNetworkError = JimengErrorHandler.handleNetworkError;
export const handlePollingTimeout = JimengErrorHandler.handlePollingTimeout;
export const handleGenerationFailure = JimengErrorHandler.handleGenerationFailure;
export const withRetry = JimengErrorHandler.withRetry;