package doumeemes.core.annotation.excel;

import doumeemes.core.constants.ResponseStatus;
import doumeemes.core.exception.BusinessException;
import lombok.AllArgsConstructor;
import lombok.Data;
import org.apache.commons.lang3.BooleanUtils;
import org.apache.commons.lang3.CharUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.math.NumberUtils;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.streaming.SXSSFWorkbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.annotation.AnnotationConfigurationException;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.math.BigDecimal;
import java.net.URLEncoder;
import java.nio.charset.Charset;
import java.text.SimpleDateFormat;
import java.util.*;
import java.util.stream.Collectors;
import java.util.stream.Stream;

/**
 * Excel导出实现
 * @author Eva.Caesar Liu
 * @date 2022/04/18 18:12
 */
@Data
public class ExcelExporter<T> {

    private static final String DEFAULT_SHEET_NAME = "Sheet1";

    private Class<T> modelClass;

    private ExcelExporter(){}



    private final static Logger log = LoggerFactory.getLogger(ExcelExporter.class);

    private final static String EXCEL2003 = "xls";
    private final static String EXCEL2007 = "xlsx";

    /**
     * 构造器
     * @param modelClass 实体Class对象
     */
    public static <T> ExcelExporter<T> build(Class<T> modelClass) {
        ExcelExporter<T> excelExporter = new ExcelExporter<>();
        excelExporter.setModelClass(modelClass);
        return excelExporter;
    }

    /**
     * 导出到指定输出流
     * @param data 数据
     * @param sheetName Sheet名称
     * @param os 输出流
     */
    public void export (List<T> data, String sheetName, OutputStream os) {
        SXSSFWorkbook sxssfWorkbook;
        try {
            sxssfWorkbook = new SXSSFWorkbook();

            CellStyle style = sxssfWorkbook.createCellStyle();
            Sheet sheet = sxssfWorkbook.createSheet(sheetName);
            // 创建列头
            sheet.createFreezePane(0, 1);
            Row header = sheet.createRow(0);
            List<ColumnInfo> columns = this.getColumns();
            for (int columnIndex = 0; columnIndex < columns.size(); columnIndex++) {
                ColumnInfo column = columns.get(columnIndex);
                Cell cell = header.createCell(columnIndex);
                cell.setCellValue(column.columnConfig.name());
                // 列宽设置
                if (column.columnConfig.width() == -1) {
                    sheet.setColumnWidth(columnIndex, column.columnConfig.name().length() * 2 * 256);
                } else {
                    sheet.setColumnWidth(columnIndex, column.columnConfig.width() * 2 * 256);
                }
                // 设置列头单元格
                configHeaderCell(sxssfWorkbook, cell, column.columnConfig,style);
            }
            // 创建数据记录
            for (int rowIndex = 0; rowIndex < data.size(); rowIndex++) {
                Row row = sheet.createRow(rowIndex + 1);
                for (int columnIndex = 0; columnIndex < columns.size(); columnIndex++) {
                    ColumnInfo column = columns.get(columnIndex);
                    Cell cell = row.createCell(columnIndex);
                    cell.setCellValue(getCellData(column, data.get(rowIndex)));
                    // 设置数据单元格
                    configDataCell(sxssfWorkbook, cell, column.columnConfig,style);
                }
            }
            sxssfWorkbook.write(os);
            os.close();
        } catch (Exception e) {
            throw new BusinessException(ResponseStatus.EXPORT_EXCEL_ERROR, e);
        } finally {
            if (os != null) {
                try {
                    os.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    /**
     * 导出至响应流
     * @param data 数据
     * @param fileName Excel文件名
     * @param sheetName Sheet名称
     * @param response HttpServletResponse对象
     */
    public void export (List<T> data, String fileName, String sheetName, HttpServletResponse response) {
        try {
            String encodeFileName = URLEncoder.encode(fileName, Charset.forName("UTF-8").toString()) + ".xlsx";
            response.setHeader("Content-Disposition","attachment;filename=" + encodeFileName);
            response.setContentType("application/octet-stream");
            response.setHeader("eva-opera-type", "download");
            response.setHeader("eva-download-filename", encodeFileName);
            this.export(data, sheetName, response.getOutputStream());
        } catch (IOException e) {
            throw new BusinessException(ResponseStatus.EXPORT_EXCEL_ERROR, e);
        }
    }

    /**
     * 导出至响应流
     * @param data 数据
     * @param fileName Excel文件名
     * @param response HttpServletResponse对象
     */
    public void export (List<T> data, String fileName, HttpServletResponse response) {
        this.export(data, fileName, DEFAULT_SHEET_NAME, response);
    }

    /**
     * 获取列集合
     */
    private List<ColumnInfo> getColumns () {
        Map<Integer, ColumnInfo> sortedFields = new TreeMap<>();
        Field[] fields = modelClass.getDeclaredFields();
        int index = 0;
        for (Field field : fields) {
            ExcelColumn excelColumn = field.getAnnotation(ExcelColumn.class);
            if (excelColumn == null) {
                continue;
            }
            if (sortedFields.get(excelColumn.index()) != null) {
                throw new AnnotationConfigurationException("Excel column contains the same index.");
            }
            sortedFields.put(excelColumn.index() == -1 ? index : excelColumn.index(), new ColumnInfo(excelColumn, field));
            index++;
        }
        return new ArrayList<>(sortedFields.values());
    }

    /**
     * 配置数据单元格
     */
    private void configDataCell (SXSSFWorkbook workbook, Cell cell, ExcelColumn columnConfig, CellStyle style) {
     //   CellStyle style = workbook.createCellStyle();
        style.setAlignment(columnConfig.align());
        style.setVerticalAlignment(VerticalAlignment.CENTER);
        // 设置背景
        style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
        style.setFillForegroundColor(columnConfig.dataBackgroundColor().getIndex());
        // 字体
        Font font = workbook.createFont();
        font.setFontHeightInPoints(columnConfig.fontSize());
        // 字体颜色
        font.setColor(columnConfig.color().getIndex());
        // 粗体
        font.setBold(columnConfig.bold());
        // 斜体
        font.setItalic(columnConfig.italic());
        style.setFont(font);
        // 边框
        configCellBorder(style);
        cell.setCellStyle(style);
    }

    /**
     * 配置列头单元格
     */
    private void configHeaderCell (SXSSFWorkbook workbook, Cell cell, ExcelColumn columnConfig,CellStyle style) {
       // CellStyle style = workbook.createCellStyle();
        style.setAlignment(columnConfig.align());
        style.setVerticalAlignment(VerticalAlignment.CENTER);
        // 设置背景
        style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
        style.setFillForegroundColor(columnConfig.backgroundColor().getIndex());
        // 字体
        Font font = workbook.createFont();
        font.setFontHeightInPoints(columnConfig.fontSize());
        style.setFont(font);
        // 设置边框
        configCellBorder(style);
        cell.setCellStyle(style);
    }

    /**
     * 配置单元格边框
     */
    private void configCellBorder (CellStyle style) {
        style.setBorderTop(BorderStyle.THIN);
        style.setBorderRight(BorderStyle.THIN);
        style.setBorderBottom(BorderStyle.THIN);
        style.setBorderLeft(BorderStyle.THIN);
        style.setTopBorderColor(IndexedColors.GREY_50_PERCENT.getIndex());
        style.setRightBorderColor(IndexedColors.GREY_50_PERCENT.getIndex());
        style.setBottomBorderColor(IndexedColors.GREY_50_PERCENT.getIndex());
        style.setLeftBorderColor(IndexedColors.GREY_50_PERCENT.getIndex());
    }

    /**
     * 处理单元格数据
     */
    private String getCellData (ColumnInfo columnInfo, T row) throws Exception {
        columnInfo.field.setAccessible(Boolean.TRUE);
        Object value = columnInfo.field.get(row);
        columnInfo.field.setAccessible(Boolean.FALSE);
        if (value == null) {
            return "";
        }
        String stringValue = value.toString();
        // 存在自定义数据处理器
        if (!columnInfo.columnConfig.handler().equals(ExcelDataHandlerAdapter.class)) {
            try {
                Object instance = columnInfo.columnConfig.handler().newInstance();
                Method formatMethod = columnInfo.columnConfig.handler().getMethod("format", Object[].class);
                List<Object> args = new ArrayList<>();
                args.add(value);
                for (String arg : columnInfo.columnConfig.args()) {
                    args.add(arg);
                }
                value = formatMethod.invoke(instance, new Object[]{args.toArray()});
                stringValue = value.toString();
            } catch (Exception e) {
                throw new IllegalStateException("Can not format data by " + columnInfo.columnConfig.handler(), e);
            }
        }
        // 日期处理
        if (!"".equals(columnInfo.columnConfig.dateFormat()) && value instanceof Date) {
            SimpleDateFormat sdf = new SimpleDateFormat(columnInfo.columnConfig.dateFormat());
            stringValue = sdf.format((Date) value);
        }
        // 值映射
        if (!"".equals(columnInfo.columnConfig.valueMapping())) {
            String[] segs = columnInfo.columnConfig.valueMapping().split(";");
            for (String seg : segs) {
                String[] mapping = seg.split("=");
                if (value.toString().equals(mapping[0].trim())) {
                    stringValue = mapping[1].trim();
                }
            }
        }
        // 前缀处理
        stringValue = columnInfo.columnConfig.prefix() + stringValue;
        // 后缀处理
        stringValue = stringValue + columnInfo.columnConfig.suffix();
        return stringValue;
    }

    @Data
    @AllArgsConstructor
    private static class ColumnInfo {

        private ExcelColumn columnConfig;

        private Field field;
    }



    public static <T> List<T> readExcel(String path, Class<T> cls, MultipartFile file) {

        String fileName = file.getOriginalFilename();
        if (!fileName.matches("^.+\\.(?i)(xls)$") && !fileName.matches("^.+\\.(?i)(xlsx)$")) {
            log.error("上传文件格式不正确");
        }
        List<T> dataList = new ArrayList<>();
        Workbook workbook = null;
        try {
            InputStream is = file.getInputStream();
            if (fileName.endsWith(EXCEL2007)) {
                workbook = new XSSFWorkbook(is);
            }
            if (fileName.endsWith(EXCEL2003)) {
                workbook = new HSSFWorkbook(is);
            }
            if (workbook != null) {
                //类映射  注解 value-->bean columns
                Map<String, List<Field>> classMap = new HashMap<>();
                List<Field> fields = Stream.of(cls.getDeclaredFields()).collect(Collectors.toList());
                fields.forEach(
                        field -> {
                            ExcelColumn annotation = field.getAnnotation(ExcelColumn.class);
                            if (annotation != null) {
                                String value = annotation.name();
                                if (StringUtils.isBlank(value)) {
                                    return;//return起到的作用和continue是相同的 语法
                                }
                                if (!classMap.containsKey(value)) {
                                    classMap.put(value, new ArrayList<>());
                                }
                                field.setAccessible(true);
                                classMap.get(value).add(field);
                            }
                        }
                );
                //索引-->columns
                Map<Integer, List<Field>> reflectionMap = new HashMap<>(16);
                //默认读取第一个sheet
                Sheet sheet = workbook.getSheetAt(0);

                boolean firstRow = true;
                for (int i = sheet.getFirstRowNum(); i <= sheet.getLastRowNum(); i++) {
                    Row row = sheet.getRow(i);
                    //首行  提取注解
                    if (firstRow) {
                        for (int j = row.getFirstCellNum(); j <= row.getLastCellNum(); j++) {
                            Cell cell = row.getCell(j);
                            String cellValue = getCellValue(cell);
                            if (classMap.containsKey(cellValue)) {
                                reflectionMap.put(j, classMap.get(cellValue));
                            }
                        }
                        firstRow = false;
                    } else {
                        //忽略空白行
                        if (row == null) {
                            continue;
                        }
                        try {
                            T t = cls.newInstance();
                            //判断是否为空白行
                            boolean allBlank = true;
                            for (int j = row.getFirstCellNum(); j <= row.getLastCellNum(); j++) {
                                if (reflectionMap.containsKey(j)) {
                                    Cell cell = row.getCell(j);
                                    String cellValue = getCellValue(cell);
                                    if (StringUtils.isNotBlank(cellValue)) {
                                        allBlank = false;
                                    }
                                    List<Field> fieldList = reflectionMap.get(j);
                                    fieldList.forEach(
                                            x -> {
                                                try {
                                                    handleField(t, cellValue, x);
                                                } catch (Exception e) {
                                                    log.error(String.format("reflect field:%s value:%s exception!", x.getName(), cellValue), e);
                                                }
                                            }
                                    );
                                }
                            }
                            if (!allBlank) {
                                dataList.add(t);
                            } else {
                                log.warn(String.format("row:%s is blank ignore!", i));
                            }
                        } catch (Exception e) {
                            log.error(String.format("parse row:%s exception!", i), e);
                        }
                    }
                }
            }
        } catch (Exception e) {
            log.error(String.format("parse excel exception!"), e);
        } finally {
            if (workbook != null) {
                try {
                    workbook.close();
                } catch (Exception e) {
                    log.error(String.format("parse excel exception!"), e);
                }
            }
        }
        return dataList;
    }

    private static <T> void handleField(T t, String value, Field field) throws Exception {
        Class<?> type = field.getType();
        if (type == null || type == void.class || StringUtils.isBlank(value)) {
            return;
        }
        if (type == Object.class) {
            field.set(t, value);
            //数字类型
        } else if (type.getSuperclass() == null || type.getSuperclass() == Number.class) {
            if (type == int.class || type == Integer.class) {
                field.set(t, NumberUtils.toInt(value));
            } else if (type == long.class || type == Long.class) {
                field.set(t, NumberUtils.toLong(value));
            } else if (type == byte.class || type == Byte.class) {
                field.set(t, NumberUtils.toByte(value));
            } else if (type == short.class || type == Short.class) {
                field.set(t, NumberUtils.toShort(value));
            } else if (type == double.class || type == Double.class) {
                field.set(t, NumberUtils.toDouble(value));
            } else if (type == float.class || type == Float.class) {
                field.set(t, NumberUtils.toFloat(value));
            } else if (type == char.class || type == Character.class) {
                field.set(t, CharUtils.toChar(value));
            } else if (type == boolean.class) {
                field.set(t, BooleanUtils.toBoolean(value));
            } else if (type == BigDecimal.class) {
                field.set(t, new BigDecimal(value));
            }
        } else if (type == Boolean.class) {
            field.set(t, BooleanUtils.toBoolean(value));
        } else if (type == Date.class) {
            field.set(t, value);
        } else if (type == String.class) {
            field.set(t, value);
        } else {
            Constructor<?> constructor = type.getConstructor(String.class);
            field.set(t, constructor.newInstance(value));
        }
    }

    private static String getCellValue(Cell cell) {
        if (cell == null) {
            return "";
        }else{
            return StringUtils.trimToEmpty(cell.getStringCellValue());
        }
       /* if (cell.getCellType() == Cell.CELL_TYPE_NUMERIC) {
            if (HSSFDateUtil.isCellDateFormatted(cell)) {
                return HSSFDateUtil.getJavaDate(cell.getNumericCellValue()).toString();
            } else {
                return new BigDecimal(cell.getNumericCellValue()).toString();
            }
        } else if (cell.getCellType() == Cell.CELL_TYPE_STRING) {
            return StringUtils.trimToEmpty(cell.getStringCellValue());
        } else if (cell.getCellType() == Cell.CELL_TYPE_FORMULA) {
            return StringUtils.trimToEmpty(cell.getCellFormula());
        } else if (cell.getCellType() == Cell.CELL_TYPE_BLANK) {
            return "";
        } else if (cell.getCellType() == Cell.CELL_TYPE_BOOLEAN) {
            return String.valueOf(cell.getBooleanCellValue());
        } else if (cell.getCellType() == Cell.CELL_TYPE_ERROR) {
            return "ERROR";
        } else {
            return cell.toString().trim();
        }*/
    }

  /*  public static <T> void writeExcel(HttpServletResponse response, List<T> dataList, Class<T> cls, String fileName) {
        Field[] fields = cls.getDeclaredFields();
        List<Field> fieldList = Arrays.stream(fields)
                .filter(field -> {
                    ExcelColumn annotation = field.getAnnotation(ExcelColumn.class);
                    if (annotation != null && annotation.col() > 0) {
                        field.setAccessible(true);
                        return true;
                    }
                    return false;
                }).sorted(Comparator.comparing(field -> {
                    int col = 0;
                    ExcelColumn annotation = field.getAnnotation(ExcelColumn.class);
                    if (annotation != null) {
                        col = annotation.col();
                    }
                    return col;
                })).collect(Collectors.toList());

        Workbook wb = new XSSFWorkbook();
        Sheet sheet = wb.createSheet("Sheet1");
        AtomicInteger ai = new AtomicInteger();
        {
            Row row = sheet.createRow(ai.getAndIncrement());
            AtomicInteger aj = new AtomicInteger();
            //写入头部
            fieldList.forEach(field -> {
                ExcelColumn annotation = field.getAnnotation(ExcelColumn.class);
                String columnName = "";
                if (annotation != null) {
                    columnName = annotation.value();
                }
                Cell cell = row.createCell(aj.getAndIncrement());
                CellStyle cellStyle = wb.createCellStyle();
                cellStyle.setFillForegroundColor(IndexedColors.WHITE.getIndex());
                Font font = wb.createFont();
                cellStyle.setFont(font);
                cell.setCellStyle(cellStyle);
                cell.setCellValue(columnName);
            });
        }
        if (CollectionUtils.isNotEmpty(dataList)) {
            dataList.forEach(t -> {
                Row row1 = sheet.createRow(ai.getAndIncrement());
                AtomicInteger aj = new AtomicInteger();
                fieldList.forEach(field -> {
                    Class<?> type = field.getType();
                    Object value = "";
                    try {
                        value = field.get(t);
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                    Cell cell = row1.createCell(aj.getAndIncrement());
                    if (value != null) {
                        if (type == Date.class) {
                            cell.setCellValue(value.toString());
                        } else {
                            cell.setCellValue(value.toString());
                        }
                        cell.setCellValue(value.toString());
                    }
                });
            });
        }
        //冻结窗格
        wb.getSheet("Sheet1").createFreezePane(0, 1, 0, 1);
        //浏览器下载excel
        buildExcelDocument(fileName, wb, response);
    }*/

    /**
     * 浏览器下载excel
     *
     * @param fileName
     * @param wb
     * @param response
     */
/*
    private static void buildExcelDocument(String fileName, Workbook wb, HttpServletResponse response) {
        try {
            response.setContentType(MediaType.APPLICATION_OCTET_STREAM_VALUE);
            response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(fileName, "utf-8"));
            response.flushBuffer();
            wb.write(response.getOutputStream());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }*/

    /**
     * 生成excel文件
     *
     * @param path 生成excel路径
     * @param wb
     */
 /*   private static void buildExcelFile(String path, Workbook wb) {
        File file = new File(path);
        if (file.exists()) {
            file.delete();
        }
        try {
            wb.write(new FileOutputStream(file));
        } catch (Exception e) {
            e.printStackTrace();
        }
    }*/

}