import { convertToHtml } from 'mammoth';
import Vue from 'vue'

export default {
  async convertFileToHtml(url) {
    var xhr = new XMLHttpRequest();
    xhr.open('GET', Vue.prototype.javaApi+url, true);//获取文件流的接口
    xhr.send();
    xhr.responseType = "blob";//不能漏
    let xhrPromise = new Promise((resolve, reject) => {
      xhr.onload = async function () {
        if (this.status === 200) {
          // 返回的文件流，转换成blob对象
          var blob = new Blob([this.response],{ type:'application/vnd.openxmlformats-officedocument.wordprocessingml.document' });
          // 使用mammoth将Word转换为HTML
          let reader = new FileReader();
          reader.readAsArrayBuffer(blob);
          let htmlContentPromise = new Promise((resolve, reject) => {
            reader.onload = async function () {
              var arrayBuffer = xhr.response; //arrayBuffer
              const result = await convertToHtml({ arrayBuffer: arrayBuffer })
              let html = result.value.replace(//g, '')
              .replace('<h1>', '<h1 style="text-align: center;">')
              .replace(/<table>/g, '<table style="border-collapse: collapse;border: 1px solid #000;">')
              .replace(/<tr>/g, '<tr style="height: 30px;">')
              .replace(/<td>/g, '<td style="border: 1px solid #000;">')
              .replace(/<p>/g, '<p style="text-indent: 2em;">')
              .replace(/<a [^>]*>/g, "")
              .replace(/<\/a>/g, "")
              // .replace(/em/g, "cm");
              resolve(html)
            };
          })
          resolve(await htmlContentPromise)
        }

      }
    })
    return await xhrPromise
  },
  downloadIamge(imgsrc, name) {//下载图片地址和图片名
    var image = new Image();
    // 解决跨域 Canvas 污染问题
    image.setAttribute("crossOrigin", "anonymous");
    image.onload = function() {
      var canvas = document.createElement("canvas");
      canvas.width = image.width;
      canvas.height = image.height;
      var context = canvas.getContext("2d");
      context.drawImage(image, 0, 0, image.width, image.height);
      var url = canvas.toDataURL("image/png"); //得到图片的base64编码数据

      var a = document.createElement("a"); // 生成一个a元素
      var event = new MouseEvent("click"); // 创建一个单击事件
      a.download = name || "photo"; // 设置图片名称
      a.href = url; // 将生成的URL设置为a.href属性
      a.dispatchEvent(event); // 触发a的单击事件
    };
    image.src = imgsrc;
  }
};


export function transformExcel(response,tempName){
  const relType = ['application/vnd.ms-excel', 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet', 'application/vnd.ms-excel;charset=UTF-8']
  let type = response.type
  if (relType.includes(type)) {
    const blob = new Blob([response], {type: 'application/vnd.ms-excel'})
    let temp = tempName
    if(response.headers){
      const disposition = response.headers["content-disposition"]
      temp = disposition.substring(disposition.lastIndexOf('=') + 1)
    }
    let filename = decodeURI(temp)
    // 创建一个超链接，将文件流赋进去，然后实现这个超链接的单击事件
    const elink = document.createElement('a')
    elink.download = filename
    elink.style.display = 'none'
    elink.href = URL.createObjectURL(blob)
    document.body.appendChild(elink)
    elink.click()
    URL.revokeObjectURL(elink.href) // 释放URL 对象
    document.body.removeChild(elink)
  }
}