package com.ruoyi.business.utils;

import com.ruoyi.business.vo.OfficialInventoryExportVo;
import com.ruoyi.common.annotation.Excel;
import com.ruoyi.common.utils.StringUtils;
import com.ruoyi.common.utils.poi.ExcelUtil;
import jakarta.servlet.http.HttpServletResponse;
import lombok.extern.slf4j.Slf4j;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.ss.util.CellRangeAddress;
import org.apache.poi.xssf.streaming.SXSSFWorkbook;

import java.lang.reflect.Field;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

@Slf4j
public class DynamicExcelUtil<T> extends ExcelUtil<T> {
    private final List<String> dynamicHeaders;
    private final List<Field> fields;

    public DynamicExcelUtil(Class<T> clazz, List<String> dynamicHeaders) {
        super(clazz);
        this.dynamicHeaders = dynamicHeaders;
        this.fields = getAllFields(clazz);
    }

    private List<Field> getAllFields(Class<?> clazz) {
        List<Field> fields = new ArrayList<>();
        Class<?> currentClass = clazz;
        while (currentClass != null) {
            fields.addAll(Arrays.asList(currentClass.getDeclaredFields()));
            currentClass = currentClass.getSuperclass();
        }
        return fields;
    }

    @Override
    public void exportExcel(HttpServletResponse response, List<T> list, String sheetName) {
        try {
            String validSheetName = StringUtils.isBlank(sheetName) ? "Sheet1" : sheetName;

            // Create workbook directly instead of using parent's createWorkbook
            Workbook workbook = new SXSSFWorkbook();
            Sheet sheet = workbook.createSheet(validSheetName);

            // Create styles
            createCustomStyles(workbook);

            // Create dynamic header
            createDynamicHeader(sheet, workbook);

            // Fill data
            fillDynamicData(sheet, list);

            // Set response
            response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
            response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(validSheetName + ".xlsx", "UTF-8"));

            workbook.write(response.getOutputStream());
        } catch (Exception e) {
            log.error("导出Excel失败", e);
            throw new RuntimeException("导出Excel失败: " + e.getMessage(), e);
        }
    }

    private void createCustomStyles(Workbook workbook) {
        // Create basic styles similar to parent class if needed
        CellStyle headerStyle = workbook.createCellStyle();
        Font headerFont = workbook.createFont();
        headerFont.setBold(true);
        headerStyle.setFont(headerFont);
        headerStyle.setAlignment(HorizontalAlignment.CENTER);
        headerStyle.setVerticalAlignment(VerticalAlignment.CENTER);
    }

    /**
     * 创建动态表头（父表头"煤质" + 子表头）
     */
    private void createDynamicHeader(Sheet sheet, Workbook workbook) {
        // 主表头（第1行）和子表头（第2行）
        Row mainHeaderRow = sheet.createRow(0);
        Row subHeaderRow = sheet.createRow(1);

        // 创建表头样式（居中 + 加粗）
        CellStyle headerStyle = workbook.createCellStyle();
        Font headerFont = workbook.createFont();
        headerFont.setBold(true);
        headerStyle.setFont(headerFont);
        headerStyle.setAlignment(HorizontalAlignment.CENTER);
        headerStyle.setVerticalAlignment(VerticalAlignment.CENTER);

        int colIndex = 0;

        // 遍历所有字段（固定字段 + 动态字段）
        for (Field field : fields) {
            Excel excel = field.getAnnotation(Excel.class);
            if (excel != null) {
                // 1. 如果是 "煤质" 字段，跳过（后面单独处理）
                if (excel.name().equals("煤质")) {
                    continue;
                }

                // 2. 处理普通字段（非 "煤质" 的列）
                // 2.1 在主表头（第1行）设置字段名
                Cell mainHeaderCell = mainHeaderRow.createCell(colIndex);
                mainHeaderCell.setCellValue(excel.name());
                mainHeaderCell.setCellStyle(headerStyle);

                // 2.2 在子表头（第2行）留空，但合并单元格使其占据两行高度
                Cell subHeaderCell = subHeaderRow.createCell(colIndex);
                subHeaderCell.setCellStyle(headerStyle); // 保持样式一致

                // 2.3 合并当前列的第1行和第2行（垂直合并）
                sheet.addMergedRegion(new CellRangeAddress(
                        0, 1,  // 从第1行到第2行
                        colIndex, colIndex  // 当前列
                ));

                colIndex++; // 移动到下一列
            }
        }

        // 3. 处理动态字段（"煤质" 下的子表头）
        if (!dynamicHeaders.isEmpty()) {
            // 3.1 在主表头（第1行）设置 "煤质" 大标题（横向合并）
            Cell coalHeaderCell = mainHeaderRow.createCell(colIndex);
            coalHeaderCell.setCellValue("煤质");
            coalHeaderCell.setCellStyle(headerStyle);

            // 横向合并（第1行，跨越多列）
            sheet.addMergedRegion(new CellRangeAddress(
                    0, 0,  // 仅第1行
                    colIndex, colIndex + dynamicHeaders.size() - 1  // 跨越多列
            ));

            // 3.2 在子表头（第2行）设置动态字段（如 "灰分"、"硫分"）
            for (int i = 0; i < dynamicHeaders.size(); i++) {
                Cell subCell = subHeaderRow.createCell(colIndex + i);
                subCell.setCellValue(dynamicHeaders.get(i));
                subCell.setCellStyle(headerStyle);
            }
        }
    }

    /**
     * 填充数据（固定字段 + 动态字段）
     */
    private void fillDynamicData(Sheet sheet, List<T> list) {
        int rowIndex = 2; // Data starts from row 3
        CellStyle dataStyle = sheet.getWorkbook().createCellStyle();
        dataStyle.setAlignment(HorizontalAlignment.CENTER);

        for (T item : list) {
            Row row = sheet.createRow(rowIndex++);
            int colIndex = 0;

            // Fill fixed fields
            for (Field field : fields) {
                Excel excel = field.getAnnotation(Excel.class);
                if (excel != null && !excel.name().equals("煤质")) {
                    try {
                        field.setAccessible(true);
                        Object value = field.get(item);
                        Cell cell = row.createCell(colIndex++);
                        cell.setCellStyle(dataStyle);
                        setCellValue(cell, value);
                    } catch (Exception e) {
                        log.error("填充固定字段失败", e);
                        row.createCell(colIndex++).setCellValue("-");
                    }
                }
            }

            // Fill dynamic fields
            if (item instanceof OfficialInventoryExportVo vo) {
                for (String header : dynamicHeaders) {
                    Cell cell = row.createCell(colIndex++);
                    cell.setCellStyle(dataStyle);
                    cell.setCellValue(vo.getDynamicProperty(header));
                }
            }
        }
    }

    /**
     * 设置单元格值
     */
    private void setCellValue(Cell cell, Object value) {
        if (value == null) {
            cell.setCellValue("-");
        } else if (value instanceof Number) {
            cell.setCellValue(((Number) value).doubleValue());
        } else {
            cell.setCellValue(value.toString());
        }
    }
}