const config = require('../config')

function networkError(err) {
  const msg = (err && err.errMsg) || ''
  if (msg.indexOf('url not in domain list') >= 0 || msg.indexOf('合法域名') >= 0) {
    return new Error('请勾选：不校验合法域名')
  }
  return new Error('网络异常，请确认后端已启动')
}

function apiError(statusCode, body) {
  const error = new Error((body && body.message) || '请求失败')
  error.statusCode = statusCode
  return error
}

function authHeader(header) {
  const token = wx.getStorageSync('token')
  if (token) header.Authorization = token
  return header
}

function handle(statusCode, body, auth, resolve, reject) {
  if (statusCode === 401 && auth) wx.removeStorageSync('token')
  if (statusCode >= 200 && statusCode < 300 && body && body.ok !== false) {
    resolve(body.data)
    return
  }
  reject(apiError(statusCode, body))
}

function request(options) {
  const auth = !!options.auth
  const header = { 'content-type': 'application/json' }
  return new Promise((resolve, reject) => {
    wx.request({
      url: config.BASE + options.url,
      method: options.method || 'GET',
      data: options.data,
      header: auth ? authHeader(header) : header,
      success(res) {
        handle(res.statusCode, res.data || {}, auth, resolve, reject)
      },
      fail(err) {
        reject(networkError(err))
      }
    })
  })
}

function upload(options) {
  return new Promise((resolve, reject) => {
    wx.uploadFile({
      url: config.BASE + options.url,
      filePath: options.filePath,
      name: 'file',
      header: authHeader({}),
      success(res) {
        let body = null
        try {
          body = JSON.parse(res.data || '{}')
        } catch (error) {
          reject(new Error('上传返回异常'))
          return
        }
        handle(res.statusCode, body, true, resolve, reject)
      },
      fail(err) {
        reject(networkError(err))
      }
    })
  })
}

module.exports = { request: request, upload: upload }