(function () {
    const ALLOWED = ['en', 'fr'];
    const params = new URLSearchParams(location.search);
    const param = (params.get('language') || '').toLowerCase();
    const paramLang = ALLOWED.includes(param) ? param : null;
    const hasParam = !!paramLang;

    // helpers
    function setCookie(name, value) {
        try {
            document.cookie = `${name}=${value}; path=/; max-age=31536000; SameSite=Lax`;
        } catch (e) { }
    }
    function clearCookie(name) {
        try { document.cookie = `${name}=; expires=Thu, 01 Jan 1970 00:00:00 GMT; path=/;`; } catch (e) { }
    }
    function setCookiesFor(lang) {
        if (!lang) return;
        setCookie('gtranslate_lng', lang);
        setCookie('googtrans', `/en/${lang}`);
    }
    function parseCookieLang() {
        const m = document.cookie.match(/(?:googtrans=\/\w+\/|gtranslate_lng=)([a-zA-Z-]+)/);
        return m ? m[1] : null;
    }
    function storageGet() {
        try {
            const ls = localStorage.getItem('selected_language');
            if (ls && ALLOWED.includes(ls)) return ls;
        } catch (e) { }
        return parseCookieLang();
    }
    function storageSet(lang) {
        if (!lang) return;
        try { localStorage.setItem('selected_language', lang); } catch (e) { }
        setCookiesFor(lang);
    }
    function storageClear() {
        try { localStorage.removeItem('selected_language'); } catch (e) { }
        clearCookie('gtranslate_lng'); clearCookie('googtrans');
    }

    // widget settings (leave default_language stable)
    window.gtranslateSettings = {
        default_language: 'en',
        detect_browser_language: true,
        languages: ALLOWED,
        wrapper_selector: '.gtranslate_wrapper',
        horizontal_position: 'right',
        vertical_position: 'bottom'
    };

    // detect current UI language from available controls
    function detectUILang() {
        const google = document.querySelector('.goog-te-combo');
        if (google && google.value) return google.value;
        const gtSel = document.querySelector('.gt_selector');
        if (gtSel && gtSel.value) {
            const parts = gtSel.value.split('|');
            return parts[parts.length - 1];
        }
        const activeLink = document.querySelector('a[data-gt-lang].active') || document.querySelector('a[data-gt-lang].selected');
        if (activeLink) return activeLink.getAttribute('data-gt-lang');
        return parseCookieLang();
    }

    // apply language via available methods
    function applyLang(lang) {
        if (!lang) return false;
        // gtranslate API
        if (window.gtranslate && typeof window.gtranslate.translate === 'function') {
            try { window.gtranslate.translate(lang); } catch (e) { return false; }
            return true;
        }
        // data-gt-lang links
        const link = document.querySelector(`a[data-gt-lang="${lang}"]`);
        if (link) { link.click(); return true; }
        // GTranslate select
        const gtSel = document.querySelector('.gt_selector');
        if (gtSel) {
            const opt = Array.from(gtSel.options).find(o => (o.value || '').endsWith(`|${lang}`) || (o.value || '').includes(`|${lang}`) || o.value === lang);
            if (opt) { gtSel.value = opt.value; gtSel.dispatchEvent(new Event('change')); return true; }
        }
        // official Google select
        const google = document.querySelector('.goog-te-combo');
        if (google) {
            google.value = lang;
            google.dispatchEvent(new Event('change'));
            return true;
        }
        return false;
    }

    // decide target
    const stored = storageGet();
    const target = hasParam ? paramLang : (stored || 'en');
    if (hasParam) {
        if (target === 'en') storageClear(); else storageSet(target);
    } else {
        if (stored && stored !== 'en') storageSet(stored);
    }

    // poll until widget ready then apply
    window.addEventListener('load', () => {
        const START = performance.now(), TIMEOUT = 5000, INTERVAL = 150;
        (function poll() {
            if (hasParam) {
                if ((target !== 'en' && applyLang(target)) || (target === 'en' && applyLang('en'))) return;
            } else {
                if (stored && stored !== 'en' && applyLang(stored)) return;
            }
            if (performance.now() - START < TIMEOUT) setTimeout(poll, INTERVAL);
        })();

        // persist user's selection from any on-page control (only when no URL param)
        if (!hasParam) {
            document.addEventListener('click', e => {
                const el = e.target.closest('[data-gt-lang], .gt_selector, .goog-te-combo');
                if (!el) return;
                setTimeout(() => {
                    const cur = detectUILang();
                    if (cur && ALLOWED.includes(cur)) storageSet(cur);
                }, 300);
            }, true);

            // also observe DOM class change (some widgets mark translated state)
            const obs = new MutationObserver(() => {
                const cur = detectUILang();
                if (cur && ALLOWED.includes(cur)) storageSet(cur);
            });
            obs.observe(document.documentElement, { attributes: true, attributeFilter: ['class'] });
        }
    });
})();