/* bootcamp-availability.js — live remaining-seat count for the bootcamp cohort.
 *
 * Source of truth: the availability webhook (product 17 = Bootcamp Q1-2027).
 * Progressive enhancement, same spirit as buy.js — it only ever ADDS, and it can
 * never block the buy:
 *
 *   fetch OK, seats > 0   -> fill the [data-bc-seats] line with "<n> of 6 seats available"
 *                            in the page's own language; Buy stays enabled.
 *   fetch OK, seats == 0  -> say the cohort is full, point at the next one, and disable
 *                            the Buy buttons (we must not sell a full cohort).
 *   anything else         -> DO NOTHING. Timeout, network error, CORS, non-200 or an
 *                            unexpected payload leave the page exactly as it is: the static
 *                            cap text shows and the Buy buttons stay enabled. A
 *                            conversion-critical element must not fail closed.
 *
 * The count is live and authoritative, so it is never written into the HTML as a fixed
 * string — the [data-bc-seats] element ships empty and hidden.
 */
(function () {
    'use strict';

    var ENDPOINT = 'https://n8n.odoo4projects.com/webhook/ODOO4projects/available';
    var PRODUCT_ID = 17;
    var CAP = 6;                 /* the page's own cohort cap ("Limited to 6 participants") */
    var TIMEOUT_MS = 6000;

    /* The page's own words and language. "seat" = seat / Platz / plaza, as used elsewhere
       on the same page ("A seat can be transferred" / "Ein Platz ist übertragbar" /
       "Una plaza se puede transferir"). */
    var TEXT = {
        en: {
            available: function (n) { return n + ' of ' + CAP + ' seats available'; },
            full: 'This cohort is full.',
            next: 'Talk to us about the next cohort',
            href: '/support.html#contact'
        },
        de: {
            available: function (n) { return n + ' von ' + CAP + ' Plätzen frei'; },
            full: 'Dieser Kurs ist ausgebucht.',
            next: 'Sprechen Sie mit uns über den nächsten Kurs',
            href: '/de/support.html#contact'
        },
        es: {
            available: function (n) { return n + ' de ' + CAP + ' plazas disponibles'; },
            full: 'Este grupo está completo.',
            next: 'Hable con nosotros sobre el próximo grupo',
            href: '/es/support.html#contact'
        }
    };

    function lang() {
        var l = (document.documentElement.getAttribute('lang') || 'en').toLowerCase();
        if (l.indexOf('de') === 0) return 'de';
        if (l.indexOf('es') === 0) return 'es';
        return 'en';
    }

    function renderAvailable(el, n, t) {
        el.textContent = '';
        var strong = document.createElement('strong');
        strong.textContent = t.available(n);
        el.appendChild(strong);
        el.hidden = false;
    }

    function renderFull(el, t) {
        el.textContent = '';
        var strong = document.createElement('strong');
        strong.textContent = t.full;
        el.appendChild(strong);
        el.appendChild(document.createTextNode(' '));
        var a = document.createElement('a');
        a.href = t.href;
        a.textContent = t.next;
        el.appendChild(a);
        el.hidden = false;
        disableBuy();
    }

    function disableBuy() {
        var buttons = document.querySelectorAll('form[action$="/shop/post_basket"] button[type="submit"]');
        for (var i = 0; i < buttons.length; i++) {
            buttons[i].disabled = true;
            buttons[i].setAttribute('aria-disabled', 'true');
        }
    }

    /* Unwrap [{data:[...]}] or {data:[...]} and read product 17's qty_available.
       Returns a finite number >= 0, or null if the shape is not what we expect. */
    function seatsFrom(json) {
        var obj = json;
        if (Array.isArray(obj)) obj = obj[0];
        if (!obj || !Array.isArray(obj.data)) return null;
        for (var i = 0; i < obj.data.length; i++) {
            var row = obj.data[i];
            if (row && Number(row.id) === PRODUCT_ID) {
                var q = Number(row.qty_available);
                return (isFinite(q) && q >= 0) ? q : null;
            }
        }
        return null;
    }

    function run() {
        var el = document.querySelector('[data-bc-seats]');
        if (!el) return;
        if (!window.fetch || typeof AbortController === 'undefined') return; /* keep fallback */
        var t = TEXT[lang()];

        var ctrl = new AbortController();
        var timer = setTimeout(function () { ctrl.abort(); }, TIMEOUT_MS);

        fetch(ENDPOINT, {
            signal: ctrl.signal,
            headers: { 'Accept': 'application/json' },
            cache: 'no-store'
        })
            .then(function (r) {
                if (!r.ok) throw new Error('HTTP ' + r.status);
                return r.json();
            })
            .then(function (json) {
                var n = seatsFrom(json);
                if (n === null) return;                     /* unexpected payload -> keep fallback */
                if (n === 0) renderFull(el, t);
                else renderAvailable(el, n, t);
            })
            .catch(function () { /* keep fallback; Buy stays enabled */ })
            .then(function () { clearTimeout(timer); });
    }

    if (document.readyState === 'loading') {
        document.addEventListener('DOMContentLoaded', run);
    } else {
        run();
    }
})();