const express = require('express');
const fs = require('fs');
const path = require('path');

const router = express.Router();

const TABLES_DIR = path.join(__dirname, '..', '..', 'data', 'tables');
const NAME_PATTERN = /^[a-z0-9-]+$/;

router.get('/:name', (req, res) => {
  const { name } = req.params;

  if (!NAME_PATTERN.test(name)) {
    return res.status(400).json({ error: 'invalid table name' });
  }

  const filePath = path.join(TABLES_DIR, `${name}.json`);

  fs.readFile(filePath, 'utf8', (err, data) => {
    if (err) {
      if (err.code === 'ENOENT') {
        return res.status(404).json({ error: 'table not found' });
      }
      return res.status(500).json({ error: 'failed to read table' });
    }

    try {
      res.json(JSON.parse(data));
    } catch {
      res.status(500).json({ error: 'invalid table data' });
    }
  });
});

module.exports = router;