/* =========================================================
# File: script.js
# Adds: theme toggle, mobile menu, hash routing, scroll spy,
# slider, filters, lightbox, form validation.
# ========================================================= */

(function () {
  const $ = (sel, root = document) => root.querySelector(sel);
  const $$ = (sel, root = document) => [...root.querySelectorAll(sel)];

  // Theme
  $('#themeToggle')?.addEventListener('click', () => {
    const root = document.documentElement;
    const willDark = !root.classList.contains('dark');
    root.classList.toggle('dark', willDark);
    localStorage.setItem('nnai-theme', willDark ? 'dark' : 'light');
  });

  // Mobile menu
  const menuBtn = $('#menuBtn');
  const mobileMenu = $('#mobileMenu');
  menuBtn?.addEventListener('click', () => {
    const open = !mobileMenu.classList.contains('hidden');
    mobileMenu.classList.toggle('hidden', open);
    menuBtn.setAttribute('aria-expanded', String(!open));
  });
  mobileMenu?.addEventListener('click', (e) => {
    const link = e.target.closest('[data-route]');
    if (link) {
      mobileMenu.classList.add('hidden');
      menuBtn.setAttribute('aria-expanded', 'false');
    }
  });

  // Routing
  function goTo(hash) {
    const id = (hash || '#home').replace('#','');
    const el = document.getElementById(id);
    if (!el) return;
    if (location.hash !== '#' + id) history.pushState({ id }, '', '#' + id);
    el.scrollIntoView({ behavior: 'smooth', block: 'start' });
  }
  document.addEventListener('click', (e) => {
    const a = e.target.closest('a[data-route]');
    if (!a) return;
    const href = a.getAttribute('href');
    if (href?.startsWith('#')) {
      e.preventDefault(); goTo(href);
    }
  });
  window.addEventListener('popstate', (e) => {
    const id = (e.state && e.state.id) || (location.hash.replace('#','') || 'home');
    document.getElementById(id)?.scrollIntoView({ behavior: 'smooth', block: 'start' });
  });
  window.addEventListener('load', () => goTo(location.hash || '#home'));

  // Scroll spy
  const sections = $$('.section');
  const navLinks = $$('.nav-link');
  const spy = new IntersectionObserver((entries) => {
    entries.forEach((entry) => {
      const id = entry.target.id;
      const link = navLinks.find((a) => a.getAttribute('href') === '#' + id);
      if (!link) return;
      if (entry.isIntersecting) { navLinks.forEach(l => l.classList.remove('active')); link.classList.add('active'); }
    });
  }, { rootMargin: '-40% 0px -55% 0px', threshold: 0.01 });
  sections.forEach((s) => spy.observe(s));

  // Slider (simple, accessible)
  const slides = $$('.slide');
  let idx = slides.findIndex(s => s.classList.contains('is-active'));
  if (idx < 0) idx = 0, slides[0]?.classList.add('is-active');
  function show(i) {
    if (!slides.length) return;
    slides[idx]?.classList.remove('is-active');
    idx = (i + slides.length) % slides.length;
    slides[idx]?.classList.add('is-active');
  }
  $('.slider-btn.prev')?.addEventListener('click', () => show(idx - 1));
  $('.slider-btn.next')?.addEventListener('click', () => show(idx + 1));
  let auto = setInterval(() => show(idx + 1), 6000);
  // Pause on hover/focus
  const slider = $('.slider');
  slider?.addEventListener('mouseenter', () => clearInterval(auto));
  slider?.addEventListener('mouseleave', () => auto = setInterval(() => show(idx + 1), 6000));

  // Portfolio filter
  const grid = $('#portfolioGrid');
  const filterButtons = $$('.filter-chip');
  filterButtons.forEach((btn) => {
    btn.addEventListener('click', () => {
      filterButtons.forEach((b) => b.classList.remove('active'));
      btn.classList.add('active');
      const f = btn.dataset.filter;
      $$('.portfolio-card', grid).forEach((card) => {
        card.style.display = (f === '*' || card.dataset.cat === f) ? '' : 'none';
      });
    });
  });

  // Lightbox
  const dlg = $('#lightbox');
  const dlgImg = $('#lightboxImg');
  const dlgClose = $('#lightboxClose');
  function openLightbox(url) {
    dlgImg.src = url;
    if (typeof dlg.showModal === 'function') dlg.showModal();
    else dlg.setAttribute('open','true');
  }
  function closeLightbox() {
    dlgImg.src = '';
    if (typeof dlg.close === 'function') dlg.close();
    else dlg.removeAttribute('open');
  }
  document.addEventListener('click', (e) => {
    const card = e.target.closest('[data-lightbox]');
    if (!card) return;
    e.preventDefault(); openLightbox(card.dataset.lightbox);
  });
  dlgClose?.addEventListener('click', closeLightbox);
  dlg?.addEventListener('click', (e) => {
    const rect = dlgImg.getBoundingClientRect();
    const inside = e.clientX >= rect.left && e.clientX <= rect.right && e.clientY >= rect.top && e.clientY <= rect.bottom;
    if (!inside) closeLightbox();
  });
  document.addEventListener('keydown', (e) => { if (e.key === 'Escape' && dlg?.open) closeLightbox(); });

  // Contact form validation
  const form = $('#contactForm');
  const formMsg = $('#formMsg');
  form?.addEventListener('submit', (e) => {
    if (!form.checkValidity()) {
      e.preventDefault();
      formMsg.textContent = '❗ Please complete all required fields correctly.';
      formMsg.className = 'text-sm text-red-600 dark:text-red-400';
      return;
    }
    formMsg.textContent = '✔️ Sending...';
    formMsg.className = 'text-sm text-slate-600 dark:text-slate-300';
  });

})();