<template>
  <!--  图片、pdf、docx 预览
          "docx-preview": "^0.1.4",
          "jszip": "^3.10.0",-->
  <div>
    <a-modal title="文件预览" :visible="showDoc || showPdf || showImg" :maskClosable="false" @cancel="cancel"
             width="750px">
      <template slot="closeIcon">
        <my-icon icon="close-circle" class="closeIcon"/>
      </template>
      <template slot="footer">
        <div v-if="showPdf" class="pdf-layout-page">
          <my-button @click="changePdfPage(0)" :disabled="currentPage===1" name="上一页"/>
          {{currentPage}} / {{pageCount}}
          <my-button @click="changePdfPage(1)" :disabled="currentPage===pageCount" name="下一页"/>
        </div>
        <my-button name="取消" @click="cancel"/>
      </template>
      <div class="modal-body form">
        <div v-if="showImg">
          <img :src="images" preview="1" preview-text="" style="width:100%"/>
        </div>
        <div v-show="showDoc" ref="word">
          <iframe v-if="fileUrl" frameborder="0"
                  :src="fileUrl"
                  width='100%'
                  height="100%">
          </iframe>
        </div>
        <div v-show="showPdf" class="pdf-layout" id="top">
          <pdf-view
            ref="pdf"
            :src="pdfPath"
            :page="currentPage"
            @num-pages="pageCount=$event"
            @page-loaded="currentPage=$event"
            @loaded="loadPdfHandler"/>
        </div>
      </div>
    </a-modal>
  </div>
</template>
<script>
  import pdfView from 'vue-pdf'
  import axios from 'axios'
  const docxPre = require('docx-preview')
  window.JSZip = require('jszip')
  export default {
    name: 'FilePreview',
    components: { pdfView },
    data() {
      return {
        showDoc: false,//判断如果是否为word文件显示
        showPdf: false,//判断如果是否为pdf文件显示
        showImg: false,//判断如果是否为图片显示
        fileUrl: '',//pdf链接
        images: '',//图片链接
        currentPage: 0, // pdf文件页码
        pageCount: 0, // pdf文件总页数
      }
    },
    methods: {
      showView(filePath) {
        let that = this
         let type = filePath.split('.')[filePath.split('.').length - 1]
        if (type === 'jpg' || type === 'png' || type === 'jpeg') {
          that.images = filePath
          that.showImg = true
        } else if (type === 'pdf') {
          that.loadPdfHandler()//重置pdf第一页展示
          that.pdfPath = filePath
          that.showPdf = true
        } else if (type === 'doc') {//word预览 
          that.fileUrl = 'https://view.officeapps.live.com/op/view.aspx?src=' + filePath
          that.showDoc = true
        } else if (type === 'docx') {//word预览
          that.showDoc = true
          that.previewWord(filePath)
        }
      },
      // 后端返回二进制流
      previewWord(filePath) {
        let that = this
        // 这里需要提起打开弹窗，因为有时很找不到word的ref 会报错
        axios({
          method: 'get',
          responseType: 'blob', // 因为是流文件，所以要指定blob类型
          url: filePath  
        }).then(({ data }) => {
          docxPre.renderAsync(data, this.$refs.word)
        })
      },
      //pdf上一页下一页操作
      changePdfPage(val) { 
        if (val === 0 && this.currentPage > 1) {
          this.currentPage-- 
        }
        if (val === 1 && this.currentPage < this.pageCount) {
          this.currentPage++
          this.top()
        }
      },
      top() {
        document.querySelector('#top').scrollIntoView(true)
      },
      // pdf加载时
      loadPdfHandler(e) {
        this.currentPage = 1 // 加载的时候先加载第一页
      },
      cancel() {
        this.showDoc = false//判断如果是否为word文件显示
        this.showPdf = false//判断如果是否为pdf文件显示
        this.showImg = false//判断如果是否为图片显示
      }
    }
  }
</script>
<style lang="less" scoped>
  .form {
    height: 600px;
    overflow: auto;
  } 
 .pdf-layout-page {
    left: 30%;
    margin: auto;
    display: inline-block;
    text-align: center;
    font-size: 14px;
    position: absolute
  }
</style>

<template> 
 <div>
    <file-preview ref="filePreview"/> 
  </div>
</template>
<script>
//组件中引入 
import FilePreview from '@/components/FilePreview/index'
 export default {
    components: { FilePreview  },
     methods: {
      lookFile() {
        this.$refs.filePreview.showView(fileUrl)
      }
  }
} 
</script>