<template>
  <el-dialog
      title="导入"
      element-loading-text="正在导入..."
      :visible.sync="show"
      :append-to-body="false"
      :modal-append-to-body="false"
      :fullscreen="true"
      v-loading="loading"
      :modal="false"
    >
      <!-- v-loading.fullscreen.lock="loading" -->
      <el-button
        type="success"
        size="mini"
        icon="el-icon-download"
        @click="postImportDown"
        >获取模板</el-button
      >
      <!-- <el-button
        type="warning"
        size="mini"
        icon="el-icon-upload"
        @click="postImportDown"
        >导入数据</el-button
      > -->
      <input ref="excel-upload-input" class="excel-upload-input" type="file" accept=".xlsx, .xls" @change="handleClick">
      <el-button 
        :loading="loading" 
        style="margin-left:16px;" 
        size="mini" 
        type="primary" 
        @click="handleUpload"
        icon="el-icon-download"
      >
        导入数据
      </el-button>
      <!-- <el-button 
        :loading="loading" 
        style="margin-left:16px;" 
        size="mini" 
        type="warning" 
        @click="handlePrint()"
        icon="el-icon-printer"
      >
        全部打印
      </el-button> -->
      <!-- <div class="drop" @drop="handleDrop" @dragover="handleDragover" @dragenter="handleDragover">
        Drop excel file here or
        <el-button :loading="loading" style="margin-left:16px;" size="mini" type="primary" @click="handleUpload">
          Browse
        </el-button>
      </div> -->
      <div style="height:calc(100% - 60px)" id="tableOuter">
        <el-table 
          :data="excelData.results" 
          border 
          highlight-current-row 
          style="width: 100%;margin-top:20px;"
          :max-height="tableMaxHeight"
        >
          <!-- @selection-change="handleSelectionPrint" -->
          <!-- <el-table-column type="selection" width="55"></el-table-column> -->
          <el-table-column 
            v-if="excelData.header.length > 0" 
            type="index" 
            fixed="left" 
            label="序号"
            width="50"
          />
          <el-table-column 
            v-for="(item,index) of excelData.header" 
            :key="index" 
            :prop="item" 
            :label="item" 
            :fixed="headerFixed(item)"
          />
          <!-- <el-table-column v-if="excelData.header.length > 0" label="明细-箱标签" fixed="right" width="100">
            <template slot-scope="scope">
              {{scope.row['明细-箱标签']}}
            </template>
          </el-table-column> -->
          <!-- <el-table-column label="操作" fixed="right">
            <template slot-scope="scope">
              <el-button type="text" @click="handlePrint([scope.row])">打印</el-button>
            </template>
          </el-table-column> -->
        </el-table>
      </div>
      <span slot="footer" class="dialog-footer">
        <el-button @click="submitForm(0)">取 消</el-button>
        <el-button type="primary" @click="submitForm(1)">确 定</el-button>
      </span>
  </el-dialog>
</template>

<script>
import XLSX from 'xlsx'
import { mixins } from "@/mixins/mixins"

export default {
  name:"UploadExcel",
  mixins:[mixins],
  watch: {
    show () {
      this.reset()
    }
  },
  props: {
    //表头浮动项
    fixedArr:{
      type:Array,
      default: () => {
        return []
      }
    },
    fixedLeftArr:{
      type:Array,
      default:null
    },
    show: {
      type: Boolean,
      default: false
    },
    beforeUpload: Function, // eslint-disable-line
    onSuccess: Function// eslint-disable-line
  },
  data() {
    return {
      loading: false,
      excelData: {
        header: [],
        results: []
      },
      // printSelection:[],//已选打印
      tableMaxHeight:null,//表格流体最大高度
    }
  },
  methods: {
    // 数据重置
    reset(){
      this.excelData = {
        header:[],
        results:[]
      }
      this.loading = false
      // this.printSelection = [];
    },
    headerFixed(item){
      let _fix = false
      this.fixedArr.forEach(fix=>{
        if(fix.name == item){
            _fix = fix.value
        }
      })
      return _fix
    },
    /**
     * 按钮操作
     * index   0:取消，1:确定
     */
    submitForm(index) {
      this.$emit("submitForm", index,this.excelData);
    },
    // 多选
    // handleSelectionPrint(val) {
    //   this.printSelection = val;
    // },
    /**
     * 打印
     * arr 有参数为单独打印，无参数为批量打印
     */
    // handlePrint(arr){
    //   let rdlx  = "xiangbq.rdlx";
    //   let params = {
    //     "boxlabel":[]
    //   }
    //   // let printArr = arr ? arr : this.printSelection;
    //   let printArr = arr ? arr : this.excelData.results;
    //   if(!printArr || printArr.length <= 0){
    //     this.$message({
    //       message: '请选择要打印的数据',
    //       type: 'error'
    //     });
    //     return
    //   }
    // },
    postImportDown () {
      this.$emit('postImportDown')
    },
    // 成功后回显及渲染
    successShowExcel(header, results){
      this.excelData.header = header
      this.excelData.results = results
      this.tableMaxHeight = document.getElementById("tableOuter").clientHeight
      this.loading = false
    },
    generateData({ header, results }) {
      // this.excelData.header = header
      // this.excelData.results = results
      // this.tableMaxHeight = document.getElementById("tableOuter").clientHeight
      if(this.onSuccess){
        this.onSuccess(header, results).then((res_header, res_results)=>{
          let _header = res_header ? res_header : header;
          let _results = res_results ? res_results : results;
          this.successShowExcel(_header, _results)
        }).catch(err=>{
          this.loading = false
        })
      }else{
        this.successShowExcel(header, results)
      }
    },
    handleDrop(e) {
      e.stopPropagation()
      e.preventDefault()
      if (this.loading) return
      const files = e.dataTransfer.files
      if (files.length !== 1) {
        this.$message.error('Only support uploading one file!')
        return
      }
      const rawFile = files[0] // only use files[0]

      if (!this.isExcel(rawFile)) {
        this.$message.error('Only supports upload .xlsx, .xls, .csv suffix files')
        return false
      }
      this.upload(rawFile)
      e.stopPropagation()
      e.preventDefault()
    },
    handleDragover(e) {
      e.stopPropagation()
      e.preventDefault()
      e.dataTransfer.dropEffect = 'copy'
    },
    handleUpload() {
      this.$refs['excel-upload-input'].click()
    },
    handleClick(e) {
      const files = e.target.files
      const rawFile = files[0] // only use files[0]
      if (!rawFile) return
      this.upload(rawFile)
    },
    upload(rawFile) {
      this.loading = true
      this.$refs['excel-upload-input'].value = null // fix can't select the same excel

      if (!this.beforeUpload) {
        this.readerData(rawFile)
        this.loading = false
        return
      }
      const before = this.beforeUpload(rawFile)
      if (before) {
        this.readerData(rawFile)
      }
    },
    readerData(rawFile) {
      return new Promise((resolve, reject) => {
        const reader = new FileReader()
        reader.onload = e => {
          const data = e.target.result
          // const workbook = XLSX.read(data, { type: 'array',cellText:false,cellDates:true })
          const workbook = XLSX.read(data, { type: 'array'})
          const firstSheetName = workbook.SheetNames[0]
          const worksheet = workbook.Sheets[firstSheetName]
          const header = this.getHeaderRow(worksheet)
          const results = XLSX.utils.sheet_to_json(worksheet,{raw:false})
          // const results = XLSX.utils.sheet_to_json(worksheet)
          if(results.length <= 0){
            this.$message.error('导入表格内无数据，请确认后重新导入');
            this.loading = false
            return
          }
          this.generateData({ header, results })
          resolve()
          this.tab
        }
        reader.readAsArrayBuffer(rawFile)
      })
    },
    getHeaderRow(sheet) {
      const headers = []
      const range = XLSX.utils.decode_range(sheet['!ref'])
      let C
      const R = range.s.r
      /* start in the first row */
      for (C = range.s.c; C <= range.e.c; ++C) { /* walk every column in the range */
        const cell = sheet[XLSX.utils.encode_cell({ c: C, r: R })]
        /* find the cell in the first row */
        let hdr = 'UNKNOWN ' + C // <-- replace with your desired default
        if (cell && cell.t) hdr = XLSX.utils.format_cell(cell)
        headers.push(hdr)
      }
      return headers
    },
    isExcel(file) {
      return /\.(xlsx|xls|csv)$/.test(file.name)
    }
  }
}
</script>

<style scoped>
.excel-upload-input{
  display: none;
  z-index: -9999;
}
.drop{
  border: 2px dashed #bbb;
  width: 600px;
  height: 160px;
  line-height: 160px;
  margin: 0 auto;
  font-size: 24px;
  border-radius: 5px;
  text-align: center;
  color: #bbb;
  position: relative;
}
</style>
