import axios, { AxiosError, AxiosInstance, AxiosRequestConfig, AxiosResponse } from 'axios';

import type { ApiError, ApiResponse } from './types';

// 创建 Axios 实例
const createApiClient = (): AxiosInstance => {
  const baseURL = process.env.NEXT_PUBLIC_API_URL || '';

  const instance = axios.create({
    baseURL,
    timeout: 30000,
    headers: {
      'Content-Type': 'application/json',
    },
  });

  // 请求拦截器
  instance.interceptors.request.use(
    (config) => {
      // 自动添加 JWT Token
      if (typeof window !== 'undefined') {
        const token = localStorage.getItem('auth_token');
        if (token && config.headers) {
          config.headers.Authorization = `Bearer ${token}`;
        }

        // 添加企业 ID
        const companyId = localStorage.getItem('company_id');
        if (companyId && config.headers) {
          config.headers['X-Company-ID'] = companyId;
        }
      }

      return config;
    },
    (error) => {
      return Promise.reject(error);
    }
  );

  // 响应拦截器
  instance.interceptors.response.use(
    (response: AxiosResponse) => {
      return response;
    },
    (error: AxiosError<ApiError>) => {
      // 统一错误处理
      const apiError: ApiError = {
        code: 'UNKNOWN_ERROR',
        message: '未知错误',
      };

      if (error.response) {
        // 服务器返回错误
        const { data, status } = error.response;

        if (data && typeof data === 'object' && 'error' in data) {
          const errorData = data as { error: { code: string; message: string; details?: unknown } };
          apiError.code = errorData.error.code;
          apiError.message = errorData.error.message;
          apiError.details = errorData.error.details;
        } else {
          apiError.code = `HTTP_${status}`;
          apiError.message = error.message;
        }

        // 401 未授权 - 跳转登录
        if (status === 401) {
          if (typeof window !== 'undefined') {
            localStorage.removeItem('auth_token');
            localStorage.removeItem('company_id');
            window.location.href = '/login';
          }
        }
      } else if (error.request) {
        // 请求发送但无响应
        apiError.code = 'NETWORK_ERROR';
        apiError.message = '网络错误，请检查连接';
      } else {
        // 其他错误
        apiError.message = error.message;
      }

      return Promise.reject(apiError);
    }
  );

  return instance;
};

// API 客户端单例
export const apiClient = createApiClient();

// 通用请求方法封装
export const api = {
  get: async <T>(url: string, config?: AxiosRequestConfig): Promise<ApiResponse<T>> => {
    const response = await apiClient.get<T>(url, config);
    return { data: response.data, status: response.status };
  },

  post: async <T>(url: string, data?: unknown, config?: AxiosRequestConfig): Promise<ApiResponse<T>> => {
    const response = await apiClient.post<T>(url, data, config);
    return { data: response.data, status: response.status };
  },

  put: async <T>(url: string, data?: unknown, config?: AxiosRequestConfig): Promise<ApiResponse<T>> => {
    const response = await apiClient.put<T>(url, data, config);
    return { data: response.data, status: response.status };
  },

  patch: async <T>(url: string, data?: unknown, config?: AxiosRequestConfig): Promise<ApiResponse<T>> => {
    const response = await apiClient.patch<T>(url, data, config);
    return { data: response.data, status: response.status };
  },

  delete: async <T>(url: string, config?: AxiosRequestConfig): Promise<ApiResponse<T>> => {
    const response = await apiClient.delete<T>(url, config);
    return { data: response.data, status: response.status };
  },
};

export default apiClient;