const pool = require('../db/connection');

const getKPIs = async (req, res) => {
  try {
    const today = new Date().toISOString().split('T')[0];

    const [totalRooms, availableRooms, checkIns, checkOuts] = await Promise.all([
      pool.query('SELECT COUNT(*) as count FROM rooms'),
      pool.query("SELECT COUNT(*) as count FROM rooms WHERE status = 'available'"),
      pool.query("SELECT COUNT(*) as count FROM reservations WHERE check_in = $1 AND status IN ('confirmed', 'checked_in')", [today]),
      pool.query("SELECT COUNT(*) as count FROM reservations WHERE check_out = $1 AND status = 'checked_in'", [today]),
    ]);

    const total = parseInt(totalRooms.rows[0].count);
    const available = parseInt(availableRooms.rows[0].count);
    const occupancy = total > 0 ? Math.round(((total - available) / total) * 100) : 0;

    res.json({
      occupancy,
      availableRooms: available,
      totalRooms: total,
      todayCheckIns: parseInt(checkIns.rows[0].count),
      todayCheckOuts: parseInt(checkOuts.rows[0].count),
    });
  } catch (error) {
    console.error(error);
    res.status(500).json({ message: 'Error al obtener KPIs' });
  }
};

const getWeeklyRevenue = async (req, res) => {
  try {
    const result = await pool.query(`
      SELECT DATE(check_out) as day, COALESCE(SUM(total_amount), 0) as revenue
      FROM reservations
      WHERE check_out >= CURRENT_DATE - INTERVAL '7 days' AND status = 'checked_out'
      GROUP BY DATE(check_out) ORDER BY day
    `);
    res.json({ weeklyRevenue: result.rows });
  } catch (error) {
    console.error(error);
    res.status(500).json({ message: 'Error al obtener ingresos semanales' });
  }
};

const getTodayArrivals = async (req, res) => {
  try {
    const today = new Date().toISOString().split('T')[0];
    const result = await pool.query(`
      SELECT r.id, r.check_in, r.check_out, r.room_id, r.status,
             g.first_name, g.last_name, g.phone
      FROM reservations r
      JOIN guests g ON g.id = r.guest_id
      WHERE (r.check_in = $1 OR r.check_out = $1)
        AND r.status IN ('confirmed', 'checked_in')
      ORDER BY r.check_in
    `, [today]);
    res.json({ arrivals: result.rows });
  } catch (error) {
    console.error(error);
    res.status(500).json({ message: 'Error al obtener llegadas' });
  }
};

module.exports = { getKPIs, getWeeklyRevenue, getTodayArrivals };