import express from 'express';
import multer from 'multer';
import * as XLSX from 'xlsx';

const router = express.Router();
const upload = multer({ storage: multer.memoryStorage() });

// 批量导入接口
router.post('/import', upload.single('file'), (req: any, res: any) => {
  try {
    if (!req.file) {
      return res.status(400).json({ code: 400, message: 'No file uploaded' });
    }
    // 读取 Excel 文件
    const workbook = XLSX.read(req.file.buffer, { type: 'buffer' });
    // 获取第一个工作表
    const sheetName = workbook.SheetNames[0];
    const worksheet = workbook.Sheets[sheetName];
    // 转换为 JSON
    const jsonData = XLSX.utils.sheet_to_json(worksheet);

    res.json({
      code: 200,
      message: 'Import successful',
      data: jsonData,
      count: jsonData.length
    });
  } catch (error: any) {
    console.error('Import error:', error);
    res.status(500).json({ code: 500, message: 'Import failed', error: error.message });
  }
});

// 批量导出接口
router.get('/export', (req: any, res: any) => {
  try {
    // 模拟数据 (实际应从数据库获取)
    const data = [
      { id: 1, name: 'Alice', email: 'alice@example.com', role: 'admin' },
      { id: 2, name: 'Bob', email: 'bob@example.com', role: 'user' },
      { id: 3, name: 'Charlie', email: 'charlie@example.com', role: 'user' }
    ];

    // 创建工作簿和工作表
    const workbook = XLSX.utils.book_new();
    const worksheet = XLSX.utils.json_to_sheet(data);
    
    // 将工作表添加到工作簿
    XLSX.utils.book_append_sheet(workbook, worksheet, 'Users');

    // 生成 Buffer
    const buffer = XLSX.write(workbook, { type: 'buffer', bookType: 'xlsx' });

    // 设置响应头
    res.setHeader('Content-Disposition', 'attachment; filename="export.xlsx"');
    res.setHeader('Content-Type', 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet');
    
    // 发送文件
    res.send(buffer);
  } catch (error: any) {
    console.error('Export error:', error);
    res.status(500).json({ code: 500, message: 'Export failed', error: error.message });
  }
});

export default router;