// server.js
const express = require('express');
const bodyParser = require('body-parser');
const sqlite3 = require('sqlite3').verbose();
const path = require('path');
const http = require('http');
const { Server } = require('socket.io');

const app = express();
const server = http.createServer(app);
const io = new Server(server);

app.use(bodyParser.json());
app.use(express.static(path.join(__dirname, 'public')));

// open (or create) the SQLite database file
const db = new sqlite3.Database('positions.db', err => {
  if (err) {
    console.error('Could not open DB', err);
    process.exit(1);
  }
});

// create table if not exists
db.run(
  `CREATE TABLE IF NOT EXISTS positions (
     square_id TEXT PRIMARY KEY,
     fruit     TEXT
   )`,
  (err) => {
    if (err) console.error('Could not ensure table', err);
  }
);

// get all saved positions
app.get('/api/positions', (req, res) => {
  db.all('SELECT square_id, fruit FROM positions', (err, rows) => {
    if (err) return res.status(500).json({ error: err.message });
    // convert to an object. should look like this: { "1": "Apple", "2": "Banana", … }
    const mapping = {};
    rows.forEach(r => (mapping[r.square_id] = r.fruit));
    res.json(mapping);
  });
});

// save (or update) a single square’s item
app.post('/api/positions', (req, res) => {
  const { squareId, fruit } = req.body;
  if (!squareId || typeof fruit !== 'string') {
    return res.status(400).json({ error: 'squareId and fruit required' });
  }
  db.run(
    `INSERT INTO positions (square_id, fruit)
     VALUES (?, ?)
     ON CONFLICT(square_id) DO UPDATE SET fruit=excluded.fruit`,
    [squareId, fruit],
    function (err) {
      if (err) return res.status(500).json({ error: err.message });
      // broadcast update via Socket.io
      io.emit('update', { squareId, fruit });
      res.json({ success: true });
    }
  );
});

// start server
const PORT = process.env.PORT || 3085;
server.listen(PORT, () => {
  console.log(`Listening on http://localhost:${PORT}`);
});