import Tools from 'Tools'
import es6 from '../assets/plugins/es6-promise'

class Service {
 constructor() {
  this.__init()
 }

 /**
  * __init
  */
 __init() {
  this.tools = new Tools
  this.__initDefaults()
  this.__initMethods()
 }


 /**
  * __initDefaults
  */
 __initDefaults() {
  // 缓存非异步方法
  this.noPromiseMethods = [
   'stopRecord',
   'pauseVoice',
   'stopVoice',
   'pauseBackgroundAudio',
   'stopBackgroundAudio',
   'showNavigationBarLoading',
   'hideNavigationBarLoading',
   'createAnimation',
   'createContext',
   'hideKeyboard',
   'stopPullDownRefresh',
  ]

  // 缓存wx接口方法名
  this.instanceSource = {
   method: Object.keys(wx)
  }
 }

 /**
  * 遍历wx方法对象，判断是否为异步方法，是则构造promise
  */
 __initMethods() {
  for (let key in this.instanceSource) {
   this.instanceSource[key].forEach((method, index) => {
    this[method] = (...args) => {
     // 判断是否为非异步方法或以 wx.on 开头，或以 Sync 结尾的方法
     if (this.noPromiseMethods.indexOf(method) !== -1 || method.substr(0, 2) === 'on' || /\w+Sync$/.test(method)) {
      return wx[method](...args)
     }
     return this.__defaultRequest(method, ...args)
    }
   })
  }

    /**
     * 保留当前页面，跳转到应用内的某个页面
     * @param {String} url 路径
     * @param {Object} params 参数
     */
  this.navigateTo = (url, params) => {
   const $$url = this.tools.buildUrl(url, params)
   return new es6.Promise((resolve, reject) => {
    wx.navigateTo({
     url: $$url,
     success: res => resolve(res),
     fail: res => reject(res),
    })
   })
  }

  /**
  * 关闭当前页面，跳转到应用内的某个页面
  * @param {String} url 路径
  * @param {Object} params 参数
  */
  this.redirectTo = (url, params) => {
   const $$url = this.tools.buildUrl(url, params)
   return new es6.Promise((resolve, reject) => {
    wx.redirectTo({
     url: $$url,
     success: res => resolve(res),
     fail: res => reject(res),
    })
   })
  }
 }

 /**
  * 以wx下API作为底层方法
  * @param {String} method 方法名
  * @param {Object} obj  接收参数
  */
 __defaultRequest(method = '', obj = {}) {
  return new es6.Promise((resolve, reject) => {
   obj.success = (res) => resolve(res)
   obj.fail = (res) => reject(res)
   wx[method](obj)
  })
 }
}

export default Service