import type { ExportHandler } from '../type'
import { ElMessage } from 'element-plus'
import * as XLSX from 'xlsx'
import FileSaver from 'file-saver'

export default function useTableExport() {
  const exportToExcel: ExportHandler = ({
    table,
    sheetName = 'sheet1',
    fileName = '导出表格.xlsx',
    headerRowNumber = 1,
  }) => {
    try {
      const tableNode = (('$el' in table
        ? table.$el
        : table.value.$el) as HTMLElement).cloneNode(true) as HTMLElement
      // 设置了列的fixed属性后会有两个table元素，导出数据会重复，需要去掉一个table
      const fixedTable = tableNode.querySelector('.el-table__fixed')
      fixedTable && tableNode.removeChild(fixedTable)
      // 自定义的表头里包含筛选，直接导出会把筛选的下拉数据也写到表头单元格里，需要先去掉筛选弹出框
      const tableHeaderCellPopovers = tableNode.querySelectorAll(
        '.table-header-cell-popover'
      )
      tableHeaderCellPopovers.forEach(node => {
        const childNode = node.querySelector('.el-popover')
        if (childNode) {
          node.removeChild(childNode)
        }
      })
      // 生成要导出的xlsx数据对象，raw: true表示不使用excel的格式解析，输出为纯文本，sheet设置xlsx这一页的标题
      const tableBook = XLSX.utils.table_to_book(tableNode, {
        raw: true,
        sheet: sheetName,
      })
      const tableBuffer = XLSX.write(tableBook, {
        bookType: 'xlsx',
        bookSST: true,
        type: 'buffer',
        cellStyles: true,
      })
      FileSaver.saveAs(
        new Blob([tableBuffer], { type: 'application/octet-stream' }),
        fileName
      )
    } catch (error: any) {
      ElMessage.error(error.message)
    }
  }

  return {
    exportToExcel,
  }
}