package com.sercurityControl.decision.utils;

import org.apache.poi.ss.usermodel.*;
import org.apache.poi.ss.util.CellRangeAddress;
import org.apache.poi.ss.util.CellRangeAddressList;
import org.apache.poi.util.Units;
import org.apache.poi.xssf.usermodel.*;
import org.springframework.util.ObjectUtils;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.net.URLEncoder;
import java.util.Base64;
import java.util.List;
import java.util.Map;

public class ExcelExportUtil {

    public ExcelExportUtil() {
    }

    private XSSFWorkbook workbook;

    /**
     * @param data      数据集 类型String
     * @param headList  表头集合
     * @param colWidths 列宽
     */
    public static void excelFileExport(HttpServletResponse response, String fileName, List<List<Object>> data,
                                       List<List<String>> headList, List<Integer> colWidths) {
        excelFileExport(response, fileName, data, headList,null, colWidths,null,null);
    }

    public static void excelFileExport(HttpServletResponse response, String fileName, List<List<Object>> data,
                                       List<List<String>> headList, List<Integer> colWidths,List<String[]> validationList, List<Integer> validationColList) {
        excelFileExport(response, fileName, data, headList,null, colWidths,validationList,validationColList);
    }

    public static void excelFileExport(HttpServletResponse response, String fileName, List<List<Object>> data,
                                       List<List<String>> headList,List<int[]> mergeList,  List<Integer> colWidths) {
        excelFileExport(response, fileName, data, headList,mergeList,colWidths,null,null);
    }

    /**
     * @param fileName   文件名
     * @param data      数据集
     * @param headList  表头集合
     * @param mergeList 合并规则集合(数组长度只能为4)
     * @param colWidths 列宽
     * @param values 下拉选择项
     * @param colList 下拉列集合
     */
    public static void excelFileExport(HttpServletResponse response, String fileName, List<List<Object>> data,
                                       List<List<String>> headList, List<int[]> mergeList, List<Integer> colWidths,List<String[]> values, List<Integer> colList) {
        try {
            String encodeFileName = URLEncoder.encode(fileName, "UTF-8");
            response.addHeader("Content-Disposition", "attachment; filename=\"" + encodeFileName + "\"");
            ExcelExportUtil excel = new ExcelExportUtil();
            InputStream input = excel.getExcelFile(data, headList, mergeList, colWidths,values, colList);
            XSSFWorkbook wb = new XSSFWorkbook(input);
            response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset=UTF-8");
            OutputStream ouputStream = response.getOutputStream();
            wb.write(ouputStream);
            ouputStream.flush();
            ouputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }


    /**
     * 创建行元素
     *
     * @param style  样式
     * @param height 行高
     * @param value  行显示的内容
     * @param row1   起始行
     * @param row2   结束行
     * @param col1   起始列
     * @param col2   结束列
     */
    private void createRow(XSSFCellStyle style, XSSFSheet sheet, int height, String value, int row1, int row2, int col1, int col2) {
        sheet.addMergedRegion(new CellRangeAddress(row1, row2, col1, col2)); //设置从第row1行合并到第row2行，第col1列合并到col2列
        XSSFRow rows = sheet.createRow(row1); //设置第几行
        rows.setHeight((short) height); //设置行高
        XSSFCell cell = rows.createCell(col1); //设置内容开始的列
        cell.setCellStyle(style); //设置样式
        cell.setCellValue(value); //设置该行的值
    }

    /**
     * 创建样式
     *
     * @param fontSize 字体大小
     * @param bold     是否加粗
     * @return style
     */
    private XSSFCellStyle getStyle(int fontSize, boolean bold, boolean border) {
        Font font = workbook.createFont();
        font.setFontName("宋体");
        font.setFontHeightInPoints((short) fontSize);// 字体大小
        if (bold) {
            font.setBold(true);
        }
        XSSFCellStyle style = (XSSFCellStyle) workbook.createCellStyle();
        style.setFont(font); //设置字体
        style.setAlignment(HorizontalAlignment.CENTER); // 左右居中2 居右3 默认居左
        style.setVerticalAlignment(VerticalAlignment.CENTER);// 上下居中1
        XSSFDataFormat format = workbook.createDataFormat();
        style.setDataFormat(format.getFormat("@"));
        style.setWrapText(true);
        if (border) {
            style.setBorderRight(BorderStyle.MEDIUM);
            style.setBorderLeft(BorderStyle.MEDIUM);
            style.setBorderBottom(BorderStyle.MEDIUM);
            style.setBorderTop(BorderStyle.MEDIUM);
            style.setLocked(true);
        }
        return style;
    }

    /**
     * 根据数据集生成Excel，并返回Excel文件流
     *
     * @param data 数据集
     * @return ba
     * @throws IOException io异常
     */
    public InputStream getExcelFile(List<List<Object>> data, List<List<String>> headList, List<int[]> mergeList, List<Integer> colWidths,List<String[]> values, List<Integer> colList) throws IOException {
        try {
            workbook = new XSSFWorkbook();
            XSSFCellStyle cellStyle = getStyle(14, false, true);
            XSSFSheet sheet = workbook.createSheet("Sheet1");
            int startRow = createHeadCell(sheet, headList, mergeList, colWidths);
            setCellData(data, sheet, cellStyle, startRow);
            if (ObjectUtils.isEmpty(data) && !ObjectUtils.isEmpty(values)){
                for (int i = 0; i < values.size(); i++) {
                    setDropDownBox("Sheet1",values.get(i),colList.get(i),startRow);
                }
            }
            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            workbook.write(baos);
            byte[] ba = baos.toByteArray();
            return new ByteArrayInputStream(ba);
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        } finally {
            data = null;
            if (workbook != null) {
                workbook.close();
            }
        }
    }

    /**
     * 创建表头
     *
     */
    private int createHeadCell(XSSFSheet sheet, List<List<String>> headList, List<int[]> mergeList, List<Integer> colWidths) {
        /*创建表头*/
        XSSFCellStyle cellStyle = getStyle(15, false, true);
        for (int i = 0; i < headList.size(); i++) {
            XSSFRow row2 = sheet.createRow(i);
            row2.setHeight((short) 0x289);
            for (int j = 0; j < headList.get(i).size(); j++) {
                XSSFCell tempCell = row2.createCell(j);
                tempCell.setCellValue(headList.get(i).get(j));
                tempCell.setCellStyle(cellStyle);
                if (colWidths != null && j < colWidths.size() && i == 0) {
                    sheet.setColumnWidth(j, 10 * colWidths.get(j));
                }
            }
        }
        /*合并单元格
         * merge[0], merge[1] 行合并 相等为不合并
         * merge[2], merge[3] 列合并
         */
        if (!ObjectUtils.isEmpty(mergeList)) {
            for (int[] merge : mergeList) {
                if (merge.length == 4) {
                    sheet.addMergedRegion(new CellRangeAddress(merge[0], merge[1], merge[2], merge[3]));
                }
            }
        }
        // 从哪一行开始渲染表体
        return headList.size();
    }

    /**
     * 创建表体数据
     *
     * @param data      表体数据
     * @param cellStyle 样式
     * @param startRow  开始行
     */
    private void setCellData(List<List<Object>> data, XSSFSheet sheet, XSSFCellStyle cellStyle, int startRow) {
        XSSFRow row = null;
        XSSFCell cell = null;
        if (data != null && data.size() > 0) {
            for (List<Object> rowData : data) {
                row = sheet.createRow(startRow);
                row.setHeight((short) 0xB99);
                for (int j = 0; j < rowData.size();j++) {
                    cell = row.createCell(j);
                    cell.setCellStyle(cellStyle);
                    cell.setCellType(CellType.STRING);
                    cell.setCellValue(rowData.get(j) == null ? "" : String.valueOf(rowData.get(j)));
                }
                startRow++;
            }
        } else {
            for (int j = startRow; j < startRow + 100; j++) {
                row = sheet.createRow(j);
                row.setHeight((short) 0x299);
                for (int i = 0; i < sheet.getRow(0).getLastCellNum(); i++) {
                    cell = row.createCell(i);
                    cell.setCellStyle(cellStyle);
                    cell.setCellType(CellType.STRING);
                    cell.setCellValue("");
                }
            }
        }
    }

    private void setDropDownBox(String sheetName, String[] values, Integer col,int startRow) {
        //获取所有sheet页个数
        int sheetTotal = workbook.getNumberOfSheets();
        //处理下拉数据
        if (values != null && values.length != 0) {
            //新建一个sheet页
            String hiddenSheetName = "hiddenSheet";
            XSSFSheet hiddenSheet = workbook.getSheet(hiddenSheetName);
            if (hiddenSheet == null) {
                hiddenSheet = workbook.createSheet(hiddenSheetName);
                sheetTotal++;
            }
            // 获取数据起始行
            int startRowNum = hiddenSheet.getLastRowNum() + 1;
            int endRowNum = startRowNum;
            //写入下拉数据到新的sheet页中
            for (String value : values) {
                hiddenSheet.createRow(endRowNum++).createCell(0).setCellValue(value);
            }
            //将新建的sheet页隐藏掉
            workbook.setSheetHidden(sheetTotal - 1, true);
            //获取新sheet页内容
            String strFormula = hiddenSheetName + "!$A$" + ++startRowNum + ":$A$" + endRowNum;
            // 设置下拉
            XSSFSheet mainSheet = workbook.getSheet(sheetName);
            mainSheet.addValidationData(setDataValidation(strFormula, mainSheet, col, col,startRow));
        }
    }

    private DataValidation setDataValidation(String strFormula, XSSFSheet mainSheet, int firstCol, int endCol,int startRow) {
        CellRangeAddressList regions = new CellRangeAddressList(startRow, startRow + 100, firstCol, endCol);
        DataValidationHelper dvHelper = mainSheet.getDataValidationHelper();
        DataValidationConstraint dataValidationConstraint = dvHelper.createFormulaListConstraint(strFormula);
        DataValidation validation = dvHelper.createValidation(dataValidationConstraint, regions);
        validation.setSuppressDropDownArrow(true);
        return validation;
    }
}