const express = require('express');
const db = require('../db-sqlite');
const { authenticate } = require('../middleware/auth');

module.exports = function(app) {
  const router = express.Router();

  router.get('/latest', authenticate, async (req, res) => {
    try {
      const latestRateResult = await db.query('SELECT currency, rate, updated_at FROM exchange_rates ORDER BY updated_at DESC LIMIT 1');
      const latestRate = latestRateResult.rows[0];
      res.json({ success: true, data: latestRate });
    } catch (error) {
      console.error('获取最新汇率失败:', error);
      res.status(500).json({ success: false, message: '获取最新汇率失败' });
    }
  });

  router.get('/', authenticate, async (req, res) => {
    try {
      const ratesResult = await db.query('SELECT id, currency, rate, updated_at FROM exchange_rates ORDER BY updated_at DESC');
      const rates = ratesResult.rows;
      res.json({ success: true, data: rates, count: rates.length });
    } catch (error) {
      console.error('获取汇率列表失败:', error);
      res.status(500).json({ success: false, message: '获取汇率列表失败' });
    }
  });

  router.get('/history', authenticate, async (req, res) => {
    try {
      const { currency, startDate, endDate } = req.query;
      let query = 'SELECT id, currency, rate, updated_at FROM exchange_rates';
      const params = [];
      
      if (currency) {
        query += ' WHERE currency = ?';
        params.push(currency);
      }
      
      if (startDate) {
        query += (params.length > 0 ? ' AND' : ' WHERE') + ' updated_at >= ?';
        params.push(startDate);
      }
      
      if (endDate) {
        query query += ' AND updated_at <= ?';
        params.push(endDate);
      }
      
      query += ' ORDER BY updated_at DESC';
      
      const historyResult = await db.query(query, params);
      const history = historyResult.rows;
      res.json({ success: true, data: history, count: history.length });
    } catch (error) {
      console.error('获取汇率历史失败:', error);
      res.status(500).json({ success: false, message: '获取汇率历史失败' });
    }
  });

  router.post('/', authenticate, async (req, res) => {
    try {
      const { currency, rate } = req.body;
      
      if (!currency || !rate) {
        return res.status(400).json({ success: false, message: '货币和汇率为必填项' });
      }
      
      const result = await db.query(
        'INSERT INTO exchange_rates (currency, rate, updated_at) VALUES (?, ?, CURRENT_TIMESTAMP)',
        [currency, rate]
      );
      
      const newRateResult = await db.query('SELECT id, currency, rate, updated_at FROM exchange_rates WHERE id = ?', [result.lastID]);
      const newRate = newRateResult.rows[0];
      
      console.log(`汇率 ${currency} = ${rate} 更新成功，由 ${req.user.username} 操作`);
      res.json({ success: true, data: newRate });
    } catch (error) {
      console.error('更新汇率失败:', error);
      res.status(500).json({ success: false, message: '更新汇率失败' });
    }
  });

  app.use('/api/exchange-rates', router);
};