(function () {
    'use strict';

    const panel    = document.getElementById('mobileOffcanvas');
    const overlay  = document.getElementById('mobOverlay');
    const btnOpen  = document.getElementById('mobMenuOpen');
    const btnClose = document.getElementById('mobMenuClose');

    if (!panel || !overlay || !btnOpen) return;   // not on this page

    /* ── Open ── */
    function openMenu() {
        overlay.classList.add('is-visible');
        // tiny rAF delay so CSS transition triggers after display:block
        requestAnimationFrame(function () {
            requestAnimationFrame(function () {
                overlay.classList.add('is-open');
                panel.classList.add('is-open');
                btnOpen.classList.add('is-open');
                btnOpen.setAttribute('aria-expanded', 'true');
                document.body.classList.add('mob-no-scroll');
            });
        });
    }

    /* ── Close ── */
    function closeMenu() {
        overlay.classList.remove('is-open');
        panel.classList.remove('is-open');
        btnOpen.classList.remove('is-open');
        btnOpen.setAttribute('aria-expanded', 'false');
        document.body.classList.remove('mob-no-scroll');

        // wait for CSS transition before hiding overlay
        overlay.addEventListener('transitionend', function handler() {
            overlay.classList.remove('is-visible');
            overlay.removeEventListener('transitionend', handler);
        });
    }

    btnOpen.addEventListener('click', openMenu);
    if (btnClose) btnClose.addEventListener('click', closeMenu);
    overlay.addEventListener('click', closeMenu);

    /* ── Escape key ── */
    document.addEventListener('keydown', function (e) {
        if (e.key === 'Escape' && panel.classList.contains('is-open')) {
            closeMenu();
        }
    });

    /* ── Sub-menu accordion ── */
    var subParents = panel.querySelectorAll('.mob-oc__nav .menu-item-has-children > a');

    subParents.forEach(function (link) {
        link.addEventListener('click', function (e) {
            e.preventDefault();
            var parent = this.parentElement;
            var isOpen = parent.classList.contains('sub-open');

            // close all open sub-menus first
            panel.querySelectorAll('.menu-item-has-children.sub-open').forEach(function (el) {
                el.classList.remove('sub-open');
            });

            if (!isOpen) {
                parent.classList.add('sub-open');
            }
        });
    });

})();