package com.ycl.utils.poi;

import com.alibaba.excel.EasyExcelFactory;
import com.alibaba.excel.util.IoUtils;
import com.baomidou.mybatisplus.core.toolkit.CollectionUtils;
import com.google.common.collect.Lists;
import com.ycl.dataListener.EasyExcelListener;
import org.springframework.web.multipart.MultipartFile;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

public class EasyExcelImportUtils {
        /**
         * 动态获取全部列和数据体
         * [stream, parseRowNumber]
         * @return {@link List< Map< String, String>>}
         * @throws
         */
        public static List<Map<String,String>> parseExcelToData(byte[] stream, Integer parseRowNumber) {
            EasyExcelListener readListener = new EasyExcelListener();
            EasyExcelFactory.read(new ByteArrayInputStream(stream)).registerReadListener(readListener).headRowNumber(parseRowNumber).sheet(0).doRead();
            List<Map<Integer, String>> headList = readListener.getHeadList();
            if(CollectionUtils.isEmpty(headList)){
                throw new RuntimeException("Excel表头不能为空");
            }
            List<Map<Integer, String>> dataList = readListener.getDataList();
            if(CollectionUtils.isEmpty(dataList)){
                throw new RuntimeException("Excel数据内容不能为空");
            }
            //获取头部,取最后一次解析的列头数据
            Map<Integer, String> excelHeadIdxNameMap = headList.get(headList.size() -1);
            //封装数据体
            List<Map<String,String>> excelDataList = Lists.newArrayList();
            for (Map<Integer, String> dataRow : dataList) {
                Map<String,String> rowData = new LinkedHashMap<>();
                excelHeadIdxNameMap.entrySet().forEach(columnHead -> {
                    rowData.put(columnHead.getValue(), dataRow.get(columnHead.getKey()));
                });
                excelDataList.add(rowData);
            }
            return excelDataList;
        }

        /**
         * 返回导入的所有数据
         * [file]
         * @return {@link List< Map< String, String>>}
         * @throws
         */
        public static List<Map<String,String>> makeData(MultipartFile file){
            InputStream inputStream = null;//转换成输入流
            try {
                inputStream = file.getInputStream();
            } catch (IOException e) {
                e.printStackTrace();
            }
            byte[] stream = new byte[0];
            try {
                stream = IoUtils.toByteArray(inputStream);
            } catch (IOException e) {
                e.printStackTrace();
            }
            if(stream == null || stream.length == 0){
                return null;
            }
            List<Map<String,String>> dataList = parseExcelToData(stream, 1);//从动态获取全部列和数据体，默认从第一行开始解析数据
            try {
                if(inputStream != null){
                    inputStream.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
            return dataList;
        }
    }