/* ROUX — app.js */
(function () {
  'use strict';

  // ── Data (injected by Hugo into a JSON script tag)
  let POSTS = [];
  try {
    const el = document.getElementById('roux-data');
    if (el) POSTS = JSON.parse(el.textContent) || [];
  } catch (e) { console.warn('roux-data parse failed', e); }

  const STOP = new Set(['the','a','an','of','and','in','on','at','by','with','is','to','for','from','as','into','onto','its','it','that','this','but','or','be','not','no','one','two','three']);

  // ── Helpers
  function esc(s) { return String(s).replace(/[&<>"]/g, c => ({'&':'&amp;','<':'&lt;','>':'&gt;','"':'&quot;'}[c])); }

  function highlight(text, terms) {
    if (!terms.length) return esc(text);
    const re = new RegExp('(' + terms.map(t => t.replace(/[.*+?^${}()|[\]\\]/g, '\\$&')).join('|') + ')', 'ig');
    return esc(text).replace(re, '<mark class="hl">$1</mark>');
  }

  // ── Inverted search index
  const INDEX = (() => {
    const map = new Map();
    function add(token, idx, weight) {
      const t = token.toLowerCase();
      if (!t || t.length < 2 || STOP.has(t)) return;
      let b = map.get(t);
      if (!b) { b = new Map(); map.set(t, b); }
      b.set(idx, (b.get(idx) || 0) + weight);
    }
    function tok(s) { return (s || '').toLowerCase().split(/[^a-z0-9àâäéèêëîïôöùûüçœæñ]+/i).filter(Boolean); }

    POSTS.forEach((p, i) => {
      tok(p.title).forEach(t => add(t, i, 6));
      (p.categories || []).forEach(c => tok(c).forEach(t => add(t, i, 4)));
      (p.tags || []).forEach(tag => tok(tag).forEach(t => add(t, i, 5)));
      tok(p.description).forEach(t => add(t, i, 1));
      tok(p.id).forEach(t => add(t, i, 8));
    });

    return function search(q) {
      const tokens = tok(q);
      if (!tokens.length) return null;
      const perToken = tokens.map(tok => {
        const merged = new Map();
        for (const [term, b] of map) {
          if (term.startsWith(tok)) {
            const factor = term === tok ? 1.0 : tok.length / term.length;
            for (const [pi, w] of b) merged.set(pi, (merged.get(pi) || 0) + w * factor);
          }
        }
        return merged;
      });
      const first = perToken[0];
      const scores = new Map();
      for (const [idx, w] of first) {
        let total = w, ok = true;
        for (let i = 1; i < perToken.length; i++) {
          const v = perToken[i].get(idx);
          if (!v) { ok = false; break; }
          total += v;
        }
        if (ok) scores.set(idx, total);
      }
      return Array.from(scores.entries())
        .sort((a, b) => b[1] - a[1])
        .map(([i]) => POSTS[i]);
    };
  })();

  // ── Masthead date
  const mhDate = document.getElementById('mhDate');
  if (mhDate) {
    const d = new Date();
    mhDate.textContent = d.toLocaleDateString('en-GB', { day:'numeric', month:'long', year:'numeric' });
  }

  // ── Count display
  const countEl = document.getElementById('count');
  function setCount(n) {
    if (!countEl) return;
    countEl.innerHTML = `<b>${String(n).padStart(3,'0')}</b> ${n === 1 ? 'post' : 'posts'}`;
  }
  setCount(POSTS.length);

  // ── Tabs: sync active state with current URL
  function syncTabs() {
    const tabs = document.querySelectorAll('.tabs button[data-cat]');
    const path = location.pathname;
    tabs.forEach(btn => {
      const cat = btn.dataset.cat;
      const active = (cat === 'All' && (path === '/' || path === '/posts/' || path.startsWith('/posts')))
        || (cat !== 'All' && path.toLowerCase().includes(cat.toLowerCase().replace(/\s+/g, '-').replace(/[^a-z0-9-]/g, '')));
      btn.setAttribute('aria-pressed', active ? 'true' : 'false');
    });
  }
  syncTabs();

  // Tab click → navigate to category page
  document.addEventListener('click', e => {
    const btn = e.target.closest('.tabs button[data-cat]');
    if (!btn) return;
    const cat = btn.dataset.cat;
    if (cat === 'All') navigate('/');
    else navigate('/categories/' + cat.toLowerCase().replace(/[\s,]+/g, '-').replace(/[^a-z0-9-]/g, '') + '/');
  });

  // ── Search popup
  const searchInput = document.getElementById('searchInput');
  const searchPop   = document.getElementById('searchpop');

  function allCats() {
    const s = new Set();
    POSTS.forEach(p => (p.categories || []).forEach(c => s.add(c)));
    return Array.from(s).slice(0, 8);
  }
  function allTags() {
    const freq = new Map();
    POSTS.forEach(p => (p.tags || []).forEach(t => freq.set(t, (freq.get(t)||0)+1)));
    return Array.from(freq.entries()).sort((a,b)=>b[1]-a[1]).slice(0,10).map(([t])=>t);
  }

  function renderSearchPop(q) {
    if (!searchPop) return;
    if (!q) {
      const cats = allCats();
      const tags = allTags();
      searchPop.innerHTML = `
        <div class="searchpop__section">
          <div class="searchpop__label">Categories <small>${cats.length}</small></div>
          <div class="searchpop__chips">
            ${cats.map(c => `<button class="searchpop__chip" data-jump="/categories/${encodeURIComponent(c.toLowerCase().replace(/[\s,]+/g,'-').replace(/[^a-z0-9-]/g,''))}/"> ${esc(c)}</button>`).join('')}
          </div>
        </div>
        <div class="searchpop__section">
          <div class="searchpop__label">Popular tags <small>${tags.length}</small></div>
          <div class="searchpop__chips">
            ${tags.map(t => `<button class="searchpop__chip" data-jump="/tags/${encodeURIComponent(t.toLowerCase().replace(/[\s,]+/g,'-').replace(/[^a-z0-9-]/g,''))}/"> # ${esc(t)}</button>`).join('')}
          </div>
        </div>`;
      searchPop.dataset.open = 'true';
      return;
    }
    const hits = INDEX(q) || [];
    const terms = q.toLowerCase().split(/\s+/).filter(t => t.length > 1);
    if (!hits.length) {
      searchPop.innerHTML = `<div class="searchpop__section"><p style="color:var(--ink-soft);font-size:13px;font-style:italic">No plates match — try <em>gothic</em>, <em>warrior</em>, or <em>neon</em>.</p></div>`;
      searchPop.dataset.open = 'true';
      return;
    }
    const shown = hits.slice(0, 6);
    searchPop.innerHTML = `
      <div class="searchpop__section">
        <div class="searchpop__label">Plates <small>${hits.length}</small></div>
        <div class="searchpop__hits">
          ${shown.map(p => `
            <button class="searchpop__hit" data-jump="${esc(p.url)}">
              ${p.thumb ? `<img src="${esc(p.thumb)}" alt="" loading="lazy" />` : '<div style="width:44px;height:66px;background:var(--paper-2)"></div>'}
              <div>
                <div class="t">${highlight(p.title, terms)}</div>
                <div class="s">${highlight((p.categories||[]).join(', '), terms)}</div>
              </div>
              <div class="n">${esc(p.id)}</div>
            </button>`).join('')}
        </div>
      </div>`;
    searchPop.dataset.open = 'true';
  }

  if (searchInput) {
    searchInput.addEventListener('input', () => renderSearchPop(searchInput.value.trim()));
    searchInput.addEventListener('focus', () => renderSearchPop(searchInput.value.trim()));
    document.addEventListener('keydown', e => {
      if ((e.metaKey || e.ctrlKey) && e.key === 'k') { e.preventDefault(); searchInput.focus(); renderSearchPop(''); }
      if (e.key === 'Escape') closeSearch();
    });
  }

  if (searchPop) {
    searchPop.addEventListener('click', e => {
      const btn = e.target.closest('[data-jump]');
      if (btn) { closeSearch(); navigate(btn.dataset.jump); }
    });
  }

  document.addEventListener('click', e => {
    if (searchPop && searchPop.dataset.open === 'true' && !e.target.closest('.subhead')) closeSearch();
  });

  function closeSearch() {
    if (searchPop) { searchPop.dataset.open = 'false'; searchPop.innerHTML = ''; }
    if (searchInput) searchInput.blur();
  }

  // ── Lightbox
  const lb       = document.getElementById('lb');
  const lbTrack  = document.getElementById('lbTrack');
  const lbMeta   = document.getElementById('lbMeta');
  const lbThumbs = document.getElementById('lbThumbs');
  const lbIndex  = document.getElementById('lbIndex');

  let lbList  = [];  // current scoped post list
  let lbIdx   = -1;  // index into lbList
  let lbBuilt = false;

  function lbOpen(slug, scopedList) {
    lbList = scopedList || POSTS;
    const idx = lbList.findIndex(p => p.slug === slug);
    if (idx === -1) return;
    lbIdx = idx;
    if (!lbBuilt) buildLbSlides();
    lb.dataset.open = 'true';
    document.body.style.overflow = 'hidden';
    goToSlide(lbIdx, false);
    lbBuildMeta(lbList[lbIdx]);
    lbBuildThumbs();
  }

  function lbClose() {
    if (!lb) return;
    lb.dataset.open = 'false';
    document.body.style.overflow = '';
    // pop back to gallery if we're on a single-post URL
    if (window.__ROUX_OPEN_SLUG) {
      navigate('/');
    }
  }

  function buildLbSlides() {
    if (!lbTrack) return;
    lbTrack.innerHTML = lbList.map((p, i) => {
      const imgSrc = p.card || p.thumb || '';
      return `<div class="lb__slide" data-i="${i}">
        <div class="lb__frame">
          <img class="lb__img" src="${esc(imgSrc)}" alt="${esc(p.title)}" loading="lazy" />
        </div>
      </div>`;
    }).join('');
    lbBuilt = true;
    // Preload neighbors
    preloadNeighbors(lbIdx);
  }

  function goToSlide(idx, smooth = true) {
    if (!lbTrack) return;
    lbIdx = Math.max(0, Math.min(idx, lbList.length - 1));
    lbTrack.style.transition = smooth ? '' : 'none';
    lbTrack.style.transform  = `translateX(-${lbIdx * 100}%)`;
    if (!smooth) lbTrack.getBoundingClientRect(); // force reflow
    if (lbIndex) {
      lbIndex.innerHTML = `<b>${String(lbIdx + 1).padStart(3,'0')}</b> / ${lbList.length}`;
    }
    lbBuildMeta(lbList[lbIdx]);
    syncThumbs();
    preloadNeighbors(lbIdx);
  }

  function preloadNeighbors(idx) {
    if (!lbTrack) return;
    [-1, 0, 1, 2].forEach(d => {
      const ni = idx + d;
      if (ni < 0 || ni >= lbList.length) return;
      const slide = lbTrack.querySelector(`.lb__slide[data-i="${ni}"]`);
      if (!slide) return;
      const img = slide.querySelector('img');
      if (img && !img.src) img.src = lbList[ni].card || lbList[ni].thumb || '';
    });
  }

  function lbBuildMeta(p) {
    if (!lbMeta || !p) return;
    const cats = (p.categories || []).join(', ');
    const tags  = (p.tags || []).slice(0, 8);
    lbMeta.innerHTML = `
      <div class="lb__cat">${esc(cats)}</div>
      <h2 class="lb__title">${esc(p.title)}</h2>
      <p class="lb__desc">${esc(p.description)}</p>
      <dl class="lb__factgrid">
        <div class="lb__fact"><dt>Plate</dt><dd>№ ${esc(p.id)}</dd></div>
        <div class="lb__fact"><dt>Category</dt><dd>${esc((p.categories||['—'])[0])}</dd></div>
      </dl>
      <div class="lb__tags">${tags.map(t => {
        const slug = t.toLowerCase().replace(/[\s,]+/g, '-').replace(/[^a-z0-9-]/g, '');
        return `<a class="lb__tag" href="/tags/${slug}/"># ${esc(t)}</a>`;
      }).join('')}</div>
      <div class="lb__share">
        <button class="lb__sh lb__sh--primary" id="lbCopy" data-url="${esc(p.url)}">
          <svg viewBox="0 0 24 24" width="14" height="14" fill="none" stroke="currentColor" stroke-width="1.6" stroke-linecap="round" stroke-linejoin="round" aria-hidden="true"><path d="M10 13a5 5 0 0 0 7.07 0l3-3a5 5 0 1 0-7.07-7.07l-1 1"/><path d="M14 11a5 5 0 0 0-7.07 0l-3 3a5 5 0 1 0 7.07 7.07l1-1"/></svg>
          <span class="lb__sh-l">Copy link</span>
        </button>
      </div>`;

    document.getElementById('lbCopy')?.addEventListener('click', function () {
      const url = new URL(this.dataset.url, location.origin).href;
      navigator.clipboard.writeText(url).then(() => {
        this.classList.add('is-ok');
        this.querySelector('.lb__sh-l').textContent = 'Copied!';
        setTimeout(() => { this.classList.remove('is-ok'); this.querySelector('.lb__sh-l').textContent = 'Copy link'; }, 2000);
      });
    });
  }

  function lbBuildThumbs() {
    if (!lbThumbs) return;
    lbThumbs.innerHTML = lbList.map((p, i) =>
      `<button class="lb__thumb" data-i="${i}" aria-current="${i === lbIdx}" aria-label="${esc(p.title)}">
        <img src="${esc(p.thumb || p.card || '')}" alt="" loading="lazy" />
      </button>`
    ).join('');
    lbThumbs.addEventListener('click', e => {
      const btn = e.target.closest('.lb__thumb');
      if (btn) goToSlide(parseInt(btn.dataset.i));
    });
  }

  function syncThumbs() {
    if (!lbThumbs) return;
    lbThumbs.querySelectorAll('.lb__thumb').forEach((b, i) => {
      b.setAttribute('aria-current', i === lbIdx ? 'true' : 'false');
    });
    const active = lbThumbs.querySelector('.lb__thumb[aria-current="true"]');
    if (active) active.scrollIntoView({ inline: 'center', behavior: 'smooth' });
  }

  // Lightbox controls
  if (lb) {
    lb.addEventListener('click', e => {
      const act = e.target.closest('[data-act]')?.dataset.act;
      if (act === 'close') lbClose();
      else if (act === 'prev') goToSlide(lbIdx - 1);
      else if (act === 'next') goToSlide(lbIdx + 1);
    });
    document.addEventListener('keydown', e => {
      if (lb.dataset.open !== 'true') return;
      if (e.key === 'Escape')     { lbClose(); }
      if (e.key === 'ArrowLeft')  { e.preventDefault(); goToSlide(lbIdx - 1); }
      if (e.key === 'ArrowRight') { e.preventDefault(); goToSlide(lbIdx + 1); }
    });

    // Touch swipe
    let touchX = null;
    lb.addEventListener('touchstart', e => { touchX = e.touches[0].clientX; }, { passive: true });
    lb.addEventListener('touchend', e => {
      if (touchX === null) return;
      const dx = e.changedTouches[0].clientX - touchX;
      if (Math.abs(dx) > 50) { dx < 0 ? goToSlide(lbIdx + 1) : goToSlide(lbIdx - 1); }
      touchX = null;
    });
  }

  // ── Card clicks → open lightbox (no full page navigation for same-origin)
  document.addEventListener('click', e => {
    const card = e.target.closest('.card[data-slug]');
    if (!card) return;
    e.preventDefault();
    const slug = card.dataset.slug;
    const visibleSlugs = Array.from(document.querySelectorAll('.card[data-slug]')).map(c => c.dataset.slug);
    const scopedList = POSTS.filter(p => visibleSlugs.includes(p.slug));
    // Update URL without page reload
    history.pushState({ slug }, '', card.href);
    lbOpen(slug, scopedList.length ? scopedList : POSTS);
  });

  // Handle browser back/forward
  window.addEventListener('popstate', e => {
    if (lb && lb.dataset.open === 'true') {
      if (!e.state?.slug) { lb.dataset.open = 'false'; document.body.style.overflow = ''; }
    }
  });

  // ── Ribbon
  const ribbon      = document.getElementById('ribbon');
  const ribbonClose = document.getElementById('ribbonClose');
  if (ribbonClose && ribbon) {
    if (sessionStorage.getItem('ribbon-closed')) ribbon.classList.add('hidden');
    ribbonClose.addEventListener('click', () => {
      ribbon.classList.add('hidden');
      sessionStorage.setItem('ribbon-closed', '1');
    });
  }

  // ── Async page transitions (View Transitions API)
  function isSameOrigin(url) {
    try { return new URL(url).origin === location.origin; } catch { return false; }
  }

  async function navigate(url) {
    if (!isSameOrigin(url)) { location.href = url; return; }

    if (!document.startViewTransition) {
      location.href = url;
      return;
    }

    document.startViewTransition(async () => {
      const res  = await fetch(url, { headers: { 'X-Requested-With': 'fetch' } });
      const text = await res.text();
      const doc  = new DOMParser().parseFromString(text, 'text/html');

      const newContent  = doc.getElementById('content');
      const newData     = doc.getElementById('roux-data');
      const oldContent  = document.getElementById('content');

      if (newContent && oldContent) {
        oldContent.replaceWith(newContent);
      }
      if (newData) {
        try {
          POSTS = JSON.parse(newData.textContent) || [];
          lbBuilt = false; // force rebuild on next open
        } catch {}
      }

      document.title = doc.title;
      history.pushState({}, '', url);

      // Re-init page state
      setCount(POSTS.length);
      syncTabs();

      // If new page has a slug to open
      const script = doc.querySelector('script[data-open-slug]');
      const openSlug = window.__ROUX_OPEN_SLUG = doc.querySelector('[data-open-slug]')?.dataset.openSlug || null;
      if (openSlug) {
        const visibleSlugs = Array.from(document.querySelectorAll('.card[data-slug]')).map(c => c.dataset.slug);
        const scoped = POSTS.filter(p => visibleSlugs.includes(p.slug));
        lbOpen(openSlug, scoped.length ? scoped : POSTS);
      }
    });
  }

  // Intercept link clicks for async transitions
  document.addEventListener('click', e => {
    if (e.button !== 0 || e.metaKey || e.ctrlKey || e.shiftKey || e.altKey) return;
    const a = e.target.closest('a[href]');
    if (!a || a.target || a.hasAttribute('download')) return;
    if (!isSameOrigin(a.href)) return;
    // Skip lightbox card clicks (handled above)
    if (a.closest('.card[data-slug]')) return;
    // Skip anchor links
    if (a.href.includes('#')) return;
    e.preventDefault();
    navigate(a.href);
  });

  // ── On single-post pages: auto-open lightbox
  if (window.__ROUX_OPEN_SLUG && POSTS.length) {
    const visibleSlugs = Array.from(document.querySelectorAll('.card[data-slug]')).map(c => c.dataset.slug);
    const scoped = POSTS.filter(p => visibleSlugs.includes(p.slug));
    lbOpen(window.__ROUX_OPEN_SLUG, scoped.length ? scoped : POSTS);
  }

})();