import _ from 'lodash'
import axios from 'axios'

const DataFormatError = new Error('后台响应数据格式异常')

export default ({store, app, req}, inject) => {

  const service = axios.create({
    withCredentials: true,
    // 根据运行环境确定请求BaseUrl
    baseURL: process.server ? process.env.baseUrl : '/'
  })

  service.interceptors.request.use(config => {
    if (process.server) {
      // 服务器端发送请求时，使用浏览器的客户端信息和Cookie
      config.headers.cookie = req.headers.cookie || ''
      config.headers['User-Agent'] = req.headers['user-agent']
    }
    return config
  }, error => {
    return Promise.reject(error)
  })

  // Add a response interceptor to handle responses
  service.interceptors.response.use(function (response) {
    const body = response.data

    // Check whether response data is unified format `Object`.
    if (_.isString(body)) {
      return Promise.reject(DataFormatError.message)
    }

    if (!body.success) {
      return Promise.reject(body.message)
    }
    return body.data
  }, function (error) {
    // Unified handle errors
    let err = null
    if (error.response) {
      // The request was made and the server responded with a status code
      // that falls out of the range of 2xx
      const response = error.response
      err = response.data && response.data.message ? response.data.message : response
    } else if (error.request) {
      // The request was made but no response was received
      // `error.request` is an instance of XMLHttpRequest in the browser
      // and an instance of http.ClientRequest in node.js
      err = error.request
    } else {
      // Something happened in setting up the request that triggered an Error
      err = error.message
    }

    return Promise.reject(err)
  })

  inject('axios', service)
}