/**
 * Relay HTTP → WS per il push dei rulesets ai sensori.
 * Chiamato SOLO dal servizio api (internal, x-api-key).
 *
 * POST /rules/push
 *   Body: { sensors: [name, ...], type, ruleset }
 *   -> invia msgpack { _t: 'ruleset_update', type, ruleset } ad ogni sensore
 *      online tramite la connessione WS gia' stabilita.
 */

const router = require('express').Router();
const { encode } = require('@msgpack/msgpack');
const { connectedSensors } = require('../ws/handler');

const INTERNAL_KEY = process.env.INTERNAL_API_KEY;

function requireInternal(req, res, next) {
    const k = req.headers['x-api-key'];
    if (!INTERNAL_KEY || !k || k !== INTERNAL_KEY) {
        return res.status(403).json({ error: 'forbidden' });
    }
    next();
}

router.post('/push', requireInternal, (req, res) => {
    const { sensors, type, ruleset } = req.body || {};
    if (!Array.isArray(sensors) || !sensors.length) return res.status(400).json({ error: 'sensors array required' });
    if (!type || !ruleset) return res.status(400).json({ error: 'type and ruleset required' });

    const payload = { _t: 'ruleset_update', type, ruleset };
    let encoded;
    try {
        encoded = encode(payload);
    } catch (err) {
        return res.status(500).json({ error: `encode error: ${err.message}` });
    }

    const pushed = [], offline = [], errors = [];
    for (const name of sensors) {
        const ws = connectedSensors.get(name);
        if (!ws || ws.readyState !== ws.OPEN) {
            offline.push(name);
            continue;
        }
        try {
            ws.send(encoded);
            pushed.push(name);
        } catch (err) {
            errors.push({ sensor: name, error: err.message });
        }
    }

    console.log(`[RULES] push type=${type} v=${ruleset?.version?.str || '?'} → pushed=${pushed.length} offline=${offline.length} err=${errors.length}`);
    res.json({ pushed, offline, errors });
});

module.exports = router;