import axios from 'axios'
import type { AxiosResponse, AxiosError, InternalAxiosRequestConfig } from 'axios'
import type { ApiResponse } from '@/api/types'
import { ElLoading, ElNotification } from 'element-plus'
import { getStorage, setStorage, removeStorage } from '@/utils/storage'
import router from '../router'

// 定义loading实例类型，用于控制loading的显示和关闭
let loadingInstance: ReturnType<typeof ElLoading.service> | null = null
// 记录当前请求数量，防止多个请求重复显示/关闭loading
let requestCount = 0

// 显示loading的方法
const showLoading = () => {
  if (requestCount === 0 && !loadingInstance) {
    loadingInstance = ElLoading.service({
      lock: true, // 锁定屏幕滚动
      fullscreen: true, // 全屏显示
    })
  }
  requestCount++
}

// 关闭loading的方法
const hideLoading = () => {
  requestCount--
  if (requestCount <= 0) {
    if (loadingInstance) {
      loadingInstance.close()
      loadingInstance = null
    }
    requestCount = 0 // 重置计数，防止负数
  }
}

// 1. 环境自动识别 + 配置读取（核心修改：适配Vite环境变量）
const env = import.meta.env
const baseURL = env.VITE_API_BASE_URL || ''
const timeout = Number(env.VITE_REQUEST_TIMEOUT) || 10000

// 2. 创建axios实例
const service = axios.create({
  baseURL,
  timeout,
  headers: { 'Content-Type': 'application/json;charset=utf-8' },
})

// 3. 请求拦截器：直接使用 axios 内置类型
const requestInterceptor = (config: InternalAxiosRequestConfig) => {
  console.log('请求配置', config)

  // 显示loading（可通过config配置项控制是否显示，比如某些请求不需要loading）
  if (config.headers?.showLoading !== false) {
    showLoading()
  }
  // 添加token到请求头
  const token = getStorage('token')
  if (token) {
    config.headers.token = token
  }
  return config
}

const requestErrorInterceptor = (error: AxiosError) => {
  // 请求拦截器出错时也要关闭loading
  ElNotification({
    message: error.message || '未知的请求错误！',
    type: 'error',
    duration: 2000,
  })
  hideLoading()

  return Promise.reject(error)
}

service.interceptors.request.use(requestInterceptor, requestErrorInterceptor)

// 4. 响应拦截器
const responseInterceptor = <T = unknown>(response: AxiosResponse<ApiResponse<T>>) => {
  //关闭loading（无论成功失败都要关）
  hideLoading()
  if (response.headers['new_token'] !== undefined) {
    setStorage('token', response.headers['new_token'] as string)
  }
  console.log('响应response', response)
  const { data } = response
  console.log('响应数据data', data)
  // 判断业务状态码
  if (data.code == 200 || data.code == 0) {
    // 仅当业务成功时，才弹成功提示
    ElNotification({
      message: data.msg || '操作成功！',
      type: 'success',
      duration: 2000,
      customClass: 'global-notification',
    })
    return data.data
  } else {
    switch (data.code) {
      case 1:
        if (!data.msg) {
          data.msg = '未知的错误！'
        }
        break
      case -101:
        data.msg = 'token错误！'
        removeStorage('token')
        router.push({ name: 'Login' })
        break
      default:
        break;
    }

    // 其他业务失败：弹错误提示并拒绝Promise
    ElNotification({
      message: data.msg || '未知的错误！',
      type: 'error',
      duration: 2000,
      customClass: 'global-notification',
    })
    return Promise.reject(data)
  }
}

const responseErrorInterceptor = (error: AxiosError) => {
  // 响应失败，关闭loading
  hideLoading()

  // 分类处理不同类型的网络错误
  let errMsg = ''
  if (error.message === 'Network Error') {
    errMsg = '网络异常，请检查您的网络连接！'
  } else if (error.code === 'ECONNABORTED') {
    errMsg = `请求超时！请求耗时超过 ${timeout / 1000} 秒`
  } else if (error.response) {
    // 有响应状态码的错误
    const status = error.response.status
    switch (status) {
      case 401:
        errMsg = '登录状态过期，请重新登录！'
        // 可在此处添加跳转到登录页的逻辑
        break
      case 403:
        errMsg = '您没有权限访问该资源！'
        break
      case 404:
        errMsg = '请求的资源不存在！'
        break
      case 500:
        errMsg = '服务器内部错误，请稍后重试！'
        break
      default:
        errMsg = (error.response?.data as ApiResponse)?.msg || `请求失败：${status}`
    }
  } else {
    errMsg = error.message || '服务器错误'
  }

  ElNotification({
    message: errMsg,
    type: 'error',
    duration: 2000,
    customClass: 'global-notification',
  })
  return Promise.reject(error)
}

service.interceptors.response.use(responseInterceptor, responseErrorInterceptor)

// 5. 封装通用请求方法
export const request = {
  get<T = unknown>(url: string, params?: unknown, config?: InternalAxiosRequestConfig): Promise<T> {
    return service.get<ApiResponse<T>>(url, { params, ...config }).then((res) => {
      return res as T
    })
  },
  post<T = unknown>(url: string, data?: unknown, config?: InternalAxiosRequestConfig): Promise<T> {
    return service.post<ApiResponse<T>>(url, data, config).then((res) => {
      return res as T
    })
  },
}

export default service