const multer = require('multer');
const csv = require('csv-parser');
const fs = require('fs');
const upload = multer({
  dest: '../temp-files',
  limits: { fileSize: 5 * 1024 * 1024 }, // 限制文件大小为5MB
  fileFilter: (req, file, cb) => {
    if (file.mimetype === 'text/csv' || file.originalname.endsWith('.csv')) {
      cb(null, true);
    } else {
      cb(new Error('只允许上传CSV文件'));
    }
  }
});

function useUploadFileParse(app) {
  app.post('/upload-drug-csv', upload.single('file'), async (req, res) => {
    if (!req.file) {
      return res.status(400).json({ success: false, message: 'No file uploaded' });
    }
    const operator = typeof req.body.operator === 'string' ? req.body.operator : '';
    const operatorId = typeof req.body.operatorId === 'string' ? req.body.operatorId : '';
    const onSale = req.body.onSale === 'true' || req.body.onSale === true;
    if (!operator || !operatorId) {
      return res.json({ success: false, message: '参数错误' });
    }
    const { getBatchInsertDrugFn } = require('../hlw/drug-info/batch-upload');
    const { batchInsertDrug, getCount, flushBatch } = await getBatchInsertDrugFn();
    const extraInfo = {
      creator: operator,
      creatorId: operatorId,
      createTime: Date.now(),
      onSale
    };
    fs.createReadStream(req.file.path)
      .pipe(csv())
      .on('data', (data) => batchInsertDrug(data, extraInfo))
      .on('end', async () => {
        await flushBatch();
        const count = await getCount();
        fs.unlinkSync(req.file.path); // 删除临时文件
        res.json({
          success: count > 0,
          message: count > 0 ? `成功导入 ${count} 条药品信息` : '没有导入任何药品信息',
        });
      })
      .on('error', (err) => {
        res.status(500).json({ success: false, message: err.message });
      });
  });

  // 配送/线上购药药品库导入：写入 online-drug-info 集合
  app.post('/upload-online-drug-csv', upload.single('file'), async (req, res) => {
    if (!req.file) {
      return res.status(400).json({ success: false, message: 'No file uploaded' });
    }
    const operator = typeof req.body.operator === 'string' ? req.body.operator : '';
    const operatorId = typeof req.body.operatorId === 'string' ? req.body.operatorId : '';
    const onSale = req.body.onSale === 'true' || req.body.onSale === true;
    if (!operator || !operatorId) {
      return res.json({ success: false, message: '参数错误' });
    }
    const { getBatchInsertOnlineDrugFn } = require('../hlw/online-drug-info/batch-upload');
    const { batchInsertDrug, getCount, flushBatch } = await getBatchInsertOnlineDrugFn();
    const extraInfo = {
      creator: operator,
      creatorId: operatorId,
      createTime: Date.now(),
      onSale
    };
    fs.createReadStream(req.file.path)
      .pipe(csv())
      .on('data', (data) => batchInsertDrug(data, extraInfo))
      .on('end', async () => {
        await flushBatch();
        const count = await getCount();
        fs.unlinkSync(req.file.path); // 删除临时文件
        res.json({
          success: count > 0,
          message: count > 0 ? `成功导入 ${count} 条线上药品信息` : '没有导入任何药品信息',
        });
      })
      .on('error', (err) => {
        res.status(500).json({ success: false, message: err.message });
      });
  });
}

module.exports = {
  useUploadFileParse
}