const db = require('../config/db');

const getCoordinatesFromBody = (body) => {
    const lat = body?.latitud ?? body?.latitude;
    const lng = body?.longitud ?? body?.longitude;

    if (lat === undefined || lat === null || lng === undefined || lng === null) {
        return null;
    }

    return { lat, lng };
};

const upsertOnlineAvailability = async (dni, lat, lng) => {
    const [rows] = await db.query(
        `SELECT id_usuario
        FROM c_trazabilidad_online
        WHERE id_usuario = ?
        LIMIT 1`,
        [dni]
    );

    if (rows.length > 0) {
        await db.query(
            `UPDATE c_trazabilidad_online
            SET latitud = ?, longitud = ?, fecha = NOW()
            WHERE id_usuario = ?`,
            [String(lat), String(lng), dni]
        );
        return;
    }

    await db.query(
        `INSERT INTO c_trazabilidad_online
            (latitud, longitud, id_usuario, fecha)
        VALUES (?, ?, ?, NOW())`,
        [String(lat), String(lng), dni]
    );
};

const getAvailability = async (req, res) => {
    try {
        const dni = String(req.user.dni);
        const [rows] = await db.query(
            `SELECT COUNT(*) AS total
            FROM c_trazabilidad_online
            WHERE id_usuario = ?`,
            [dni]
        );

        return res.json({
            success: true,
            available: Number(rows[0]?.total || 0) > 0
        });
    } catch (error) {
        console.error('Error getting availability:', error);
        return res.status(500).json({ success: false, error: error.message });
    }
};

const setAvailability = async (req, res) => {
    try {
        const coords = getCoordinatesFromBody(req.body);

        if (!coords) {
            return res.status(400).json({
                success: false,
                error: 'missing_coords',
                message: 'latitud/longitud or latitude/longitude are required'
            });
        }

        await upsertOnlineAvailability(String(req.user.dni), coords.lat, coords.lng);

        return res.json({ success: true, available: true });
    } catch (error) {
        console.error('Error setting availability:', error);
        return res.status(500).json({ success: false, error: error.message });
    }
};

const deleteAvailability = async (req, res) => {
    try {
        await db.query(
            `DELETE FROM c_trazabilidad_online
            WHERE id_usuario = ?`,
            [String(req.user.dni)]
        );

        return res.json({ success: true, available: false });
    } catch (error) {
        console.error('Error deleting availability:', error);
        return res.status(500).json({ success: false, error: error.message });
    }
};

module.exports = {
    deleteAvailability,
    getAvailability,
    setAvailability,
    upsertOnlineAvailability
};