const express = require('express');
const cors = require('cors');
const path = require('path');
const compression = require('compression');

const config = require('./config');
const logger = require('./utils/logger');
const db = require('./db');
const { router: authRouter, auth } = require('./routes/auth');
const statsRouter = require('./routes/stats');
const recordsRouter = require('./routes/records');
const ioRouter = require('./routes/io');

const app = express();

// 请求日志中间件
app.use(logger.requestLogger);

app.use(cors());
app.use(express.json());
app.use(compression());
app.use(express.static(path.join(__dirname, '..', 'public'), {
  maxAge: '1h',
  etag: true
}));

// 联系人自动补全
app.use('/api', (req, res, next) => {
  res.setHeader('Cache-Control', 'no-cache');
  next();
});

app.get('/api/contacts', auth, (req, res) => {
  const field = req.query.field;
  const allowed = ['boss', 'partner', 'source', 'destination'];
  if (!field || !allowed.includes(field)) return res.status(400).json({ error: '无效字段' });

  const rows = db.prepare(`
    SELECT ${field} as name, MAX(created_at) as last_used, COUNT(*) as freq
    FROM records WHERE user_id = ? AND ${field} IS NOT NULL AND ${field} != ''
    GROUP BY ${field} ORDER BY MAX(created_at) DESC
  `).all(req.user.id);
  res.json(rows.map(r => r.name));
});

// 路由挂载
app.use('/api', authRouter);
app.use('/api/stats', auth, statsRouter);
app.use('/api/records', auth, recordsRouter);
app.use('/api', auth, ioRouter);

// 404 处理
app.use((req, res) => {
  res.status(404).json({ error: '接口不存在' });
});

// 全局错误处理中间件
app.use((err, req, res, next) => {
  // 记录错误日志
  logger.error('Unhandled error:', err.message, err.stack);

  // 处理特定错误类型
  if (err.name === 'UnauthorizedError') {
    return res.status(401).json({ error: '未授权访问' });
  }

  if (err.name === 'SyntaxError' && err.status === 400 && 'body' in err) {
    return res.status(400).json({ error: 'JSON 格式错误' });
  }

  // 默认错误响应
  const status = err.status || err.statusCode || 500;
  const message = err.expose ? err.message : '服务器内部错误';

  res.status(status).json({ error: message });
});

const PORT = config.port;
const HOST = config.host;
app.listen(PORT, HOST, () => {
  logger.info(`服务器运行在 http://${HOST}:${PORT}`);
});