/**获取ajax请求信息 */

// 首先拦截ajax请求，然后将这些数据依次抛出
// XMLHttpRequest 文档参考：https://developer.mozilla.org/zh-CN/docs/Web/API/XMLHttpRequest

import { innertEvent, windowCustomEventTrigger } from './utils'

import { InterceptAjaxData, AjaxEvent } from './types'

class Ajax {
  private data: InterceptAjaxData
  // 请求集合
  private requestArray: any[] = []

  constructor() {
    this.data = {};
    this.listenerAjax();
    //this.listenerFetch();
  }

  send(ajaxRoot: any, responseText: any) {
    const currentTime = new Date().getTime();
    const loadTime = currentTime - ajaxRoot.request.timeStamp;
    const responseURL = ajaxRoot.responseURL;
    const status = ajaxRoot.status;
    const statusText = ajaxRoot.statusText;

    if (ajaxRoot.request.ajaxUrl.indexOf('https://hubble.netease.com/track/w') > -1) {
      return;
    }

    innertEvent.trigger('ajax', {
      currentTime: currentTime,
      loadTime: loadTime,
      responseURL: responseURL,
      status: status,
      statusText: statusText,
      responseText: responseText && responseText.substring(0, 200),
      request: ajaxRoot.request
    })
  }
  
  /**监听ajax， 重写  XMLHttpRequest*/
  listenerAjax() {
    const root = this;
    const oldXHR = window.XMLHttpRequest;

    const oldOpen = oldXHR.prototype.open;
    const oldSend = oldXHR.prototype.send;
    oldXHR.prototype.open = function(method: string, ajaxUrl: string) {
      this.request = {
        method: method,
        ajaxUrl: ajaxUrl,
        timeStamp: new Date().getTime()
      };
      oldOpen && oldOpen.apply(this, arguments);
    };
    oldXHR.prototype.send = function(body?: any) {
      this.request.body = body;
      oldSend && oldSend.apply(this, arguments);

      const oldOnloadend = this.onloadend;
      const ajaxRoot = this;
      this.onloadend = function() {
        let responseText = '';
        const responseType = (ajaxRoot.responseType+'').toLowerCase();
        if (responseType === 'blob') {
          (function(ajaxRoot) {
            const reader = new FileReader();
            reader.onload = function() {
              const responseText = reader.result;
              root.send(ajaxRoot, responseText);
            }
            try {
              reader.readAsText(ajaxRoot.response, 'utf-8');
            } catch (e) {
              root.send(ajaxRoot, ajaxRoot.response + "");
            }
          })(ajaxRoot);
        } else {
          responseText = ajaxRoot.responseText;
        }
        root.send(ajaxRoot, responseText);
       
        oldOnloadend && oldOnloadend.apply(this, arguments);
      }
    };

    window.XMLHttpRequest = oldXHR;
    

    // const newXHR: any = function() {
    //   const realXHR = new oldXHR();
    //   realXHR.addEventListener('loadstart', function () { windowCustomEventTrigger.call(this, 'ajaxLoadStart'); }, false);
    //   realXHR.addEventListener('loadend', function () { windowCustomEventTrigger.call(this, 'ajaxLoadEnd'); }, false);
      
    //   return realXHR;
    // }

    // window.XMLHttpRequest = newXHR;

    // window.addEventListener('ajaxLoadStart', (e: Event) => {
    //   const tempObj = {
    //     timeStamp: window.performance.now(),
    //     event: e,
    //     url: window.location.href,
    //     uploadFlag: false
    //   };
    //   // 将请求保存到临时队列中
    //   this.requestArray.push(tempObj);
    //   this.requestArray = this.requestArray.filter((request) => {
    //     return !request.uploadFlag;
    //   })
    // });

    // window.addEventListener('ajaxLoadEnd', () => {
    //   this.requestArray.forEach((request: any) => {
    //     if (request && !request.uploadFlag) {
    //       // https://developer.mozilla.org/zh-CN/docs/Web/API/XMLHttpRequest/status
    //       if (request.event.detail.status > 0) {
    //         // https://developer.mozilla.org/zh-CN/docs/Web/API/XMLHttpRequest/responseType
    //         const responseType = (request.event.detail.responseType+'').toLowerCase();
    //         let responseText = '';
    //         if (responseType === 'blob') {
    //           (function(request, root) {
    //             const reader = new FileReader();
    //             reader.onload = function() {
    //               const responseText = reader.result;
    //               root.send(request, responseText);
    //             }
    //             try {
    //               reader.readAsText(request.event.detail.response, 'utf-8');
    //             } catch (e) {
    //               root.send(request, request.event.detail.response + "");
    //             }
    //           })(request, this);
    //         } else {
    //           responseText = request.event.detail.responseText
    //         }
    //         this.send(request, responseText)
    //       }
    //     } 
    //   })
    //});

  }
  
  /**监听fetch 请求， 重写 fetch */
  listenerFetch() {
    const oldFetch = window.fetch;
    const root = this;
  }
}

export default Ajax