package com.zjty.tynotes.misc.utils;

import cn.afterturn.easypoi.excel.ExcelExportUtil;
import cn.afterturn.easypoi.excel.ExcelImportUtil;
import cn.afterturn.easypoi.excel.entity.ExportParams;
import cn.afterturn.easypoi.excel.entity.ImportParams;
import cn.afterturn.easypoi.excel.entity.enmus.ExcelType;
import org.apache.commons.lang3.StringUtils;
import org.apache.poi.ss.usermodel.Workbook;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.OutputStream;
import java.net.URLEncoder;
import java.util.List;
import java.util.Map;
import java.util.NoSuchElementException;

/**
 * fp-api.
 *
 * @author : Matrix [xhyrzldf@gmail.com]
 * 18-11-15 .
 */
public class ExcelUtil {

    public static void exportExcel(List<?> list, String title, String sheetName, Class<?> pojoClass, String fileName, boolean isCreateHeader, HttpServletResponse response) {
        ExportParams exportParams = new ExportParams(title, sheetName);
        exportParams.setCreateHeadRows(isCreateHeader);
        defaultExport(list, pojoClass, fileName, response, exportParams);

    }

    public static void exportExcel(List<?> list, String title, String sheetName, Class<?> pojoClass, String fileName, HttpServletResponse response) {
        defaultExport(list, pojoClass, fileName, response, new ExportParams(title, sheetName));
    }

    public static void exportExcel(List<Map<String, Object>> list, String fileName, HttpServletResponse response) {
        defaultExport(list, fileName, response);
    }

    /**
     * @param response  HTTP response
     * @param wb        workbook
     * @param excelName excelName名称
     */
    public static void downloadExcel(HttpServletRequest request, HttpServletResponse response, Workbook wb, String excelName) {
        // 判断数据
        if (wb == null) {
            throw new CustomException("workbook can not be null!");
        }
        // 重置响应对象
        response.reset();

        String dateStr = excelName  + ".xls";
        System.out.println(dateStr);
        // 指定下载的文件名--设置响应头
        response.addHeader("Content-Disposition", "attachment;filename=" + dateStr);
        response.setContentType("application/octet-stream;charset=UTF-8");
        response.setHeader("Pragma", "no-cache");
        response.setDateHeader("Expires", 0);
        response.setHeader("Access-Control-Allow-Origin", request.getHeader("Origin"));
        response.setHeader("Access-Control-Allow-Credentials", "true");
        response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, PUT, PATCH, DELETE");
        response.setHeader("Access-Control-Max-Age", "3600");
        response.setHeader("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
        // 写出数据输出流到页面
        try {
            OutputStream output = response.getOutputStream();
            BufferedOutputStream bufferedOutPut = new BufferedOutputStream(output);
            wb.write(bufferedOutPut);
            bufferedOutPut.flush();
            bufferedOutPut.close();
            output.close();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    private static void defaultExport(List<?> list, Class<?> pojoClass, String fileName, HttpServletResponse response, ExportParams exportParams) {
        Workbook workbook = ExcelExportUtil.exportExcel(exportParams, pojoClass, list);
        downLoadExcel(fileName, response, workbook);
    }

    private static void downLoadExcel(String fileName, HttpServletResponse response, Workbook workbook) {
        try {
            response.setCharacterEncoding("UTF-8");
            response.setHeader("content-Type", "application/vnd.ms-excel");
            response.setHeader("Content-Disposition",
                    "attachment;filename=" + URLEncoder.encode(fileName, "UTF-8"));
            workbook.write(response.getOutputStream());
        } catch (IOException e) {
            throw new CustomException(e.getMessage());
        }
    }

    private static void defaultExport(List<Map<String, Object>> list, String fileName, HttpServletResponse response) {
        Workbook workbook = ExcelExportUtil.exportExcel(list, ExcelType.HSSF);
        downLoadExcel(fileName, response, workbook);
    }

    public static <T> List<T> importExcel(String filePath, Integer titleRows, Integer headerRows, Class<T> pojoClass) {
        if (StringUtils.isBlank(filePath)) {
            return null;
        }
        ImportParams params = new ImportParams();
        params.setTitleRows(titleRows);
        params.setHeadRows(headerRows);
        List<T> list;
        try {
            list = ExcelImportUtil.importExcel(new File(filePath), pojoClass, params);
        } catch (NoSuchElementException e) {
            throw new CustomException("模板不能为空");
        } catch (Exception e) {
            e.printStackTrace();
            throw new CustomException(e.getMessage());
        }
        return list;
    }

    public static <T> List<T> importExcel(MultipartFile file, Integer titleRows, Integer headerRows, Class<T> pojoClass) {
        if (file == null) {
            return null;
        }
        ImportParams params = new ImportParams();
        params.setTitleRows(titleRows);
        params.setHeadRows(headerRows);
        List<T> list;
        try {
            list = ExcelImportUtil.importExcel(file.getInputStream(), pojoClass, params);
        } catch (NoSuchElementException e) {
            throw new CustomException("excel文件不能为空");
        } catch (Exception e) {
            throw new CustomException(e.getMessage());
        }
        return list;
    }
}
