(() => {
  const hero = document.querySelector('.dbc-particle-hero#home');
  if (!hero || hero.querySelector('.v284-release-rail')) return;

  const previewCatalog = {
    product: {
      schemaVersion: 1,
      enabled: true,
      status: 'approved',
      id: 'preview-bioten-product-update',
      kind: 'product',
      publishAt: '2026-07-18T00:00:00+08:00',
      expiresAt: '2099-12-31T23:59:59+08:00',
      labelCn: '产品更新',
      labelEn: 'Update',
      titleCn: 'BIOTEN 水性阻隔乳液资料更新',
      titleEn: 'BIOTEN | Barrier emulsion',
      actionCn: '查看详情',
      actionEn: 'View update',
      href: 'bioten-products.html'
    },
    news: {
      schemaVersion: 1,
      enabled: true,
      status: 'approved',
      id: 'preview-casu-basf-news',
      kind: 'news',
      publishAt: '2026-06-12T00:00:00+08:00',
      expiresAt: '2099-12-31T23:59:59+08:00',
      labelCn: '最新动态',
      labelEn: 'News',
      titleCn: '中科联化 × 巴斯夫｜水性粘合剂协同',
      titleEn: 'CASU × BASF | Binder update',
      actionCn: '阅读全文',
      actionEn: 'Read article',
      href: 'news-2026-06-12-casu-basf-water-based-battery-binder.html'
    }
  };

  const requiredTextFields = [
    'id',
    'kind',
    'publishAt',
    'expiresAt',
    'labelCn',
    'labelEn',
    'titleCn',
    'titleEn',
    'actionCn',
    'actionEn',
    'href'
  ];

  function readReleaseConfig() {
    const source = document.getElementById('dbc-home-release-config');
    if (!source) return null;
    try {
      return JSON.parse(source.textContent || '');
    } catch (error) {
      return null;
    }
  }

  function hasCompleteFields(release) {
    return release
      && release.schemaVersion === 1
      && requiredTextFields.every((field) => typeof release[field] === 'string' && release[field].trim());
  }

  function hasTimezone(value) {
    return /^\d{4}-\d{2}-\d{2}T.+(?:Z|[+-]\d{2}:\d{2})$/.test(value);
  }

  function isSafeRelativeHtmlPath(value) {
    if (typeof value !== 'string') return false;
    const href = value.trim();
    const path = href.split(/[?#]/, 1)[0];
    if (!href || !path || href.startsWith('/') || href.startsWith('//') || href.includes('\\')) return false;
    if (/^[a-z][a-z\d+.-]*:/i.test(href)) return false;
    if (path.split('/').includes('..')) return false;
    return /\.html?$/i.test(path);
  }

  function isApprovedAndActive(release) {
    if (!hasCompleteFields(release)) return false;
    if (release.enabled !== true || release.status !== 'approved') return false;
    if (!['product', 'news', 'resource'].includes(release.kind)) return false;
    if (!hasTimezone(release.publishAt) || !hasTimezone(release.expiresAt)) return false;
    if (!isSafeRelativeHtmlPath(release.href)) return false;

    const publishAt = Date.parse(release.publishAt);
    const expiresAt = Date.parse(release.expiresAt);
    const now = Date.now();
    return Number.isFinite(publishAt)
      && Number.isFinite(expiresAt)
      && publishAt < expiresAt
      && now >= publishAt
      && now < expiresAt;
  }

  const searchParams = new URLSearchParams(window.location.search);
  const requestedPreview = searchParams.get('release');
  if (requestedPreview === 'off') return;

  const isLocalPreview = window.location.protocol === 'file:'
    || /^(?:localhost|127(?:\.\d{1,3}){3}|\[::1\])$/i.test(window.location.hostname);
  const previewRelease = isLocalPreview ? previewCatalog[requestedPreview] : null;
  const release = previewRelease || readReleaseConfig();
  if (!previewRelease && !isApprovedAndActive(release)) return;
  if (previewRelease && !hasCompleteFields(release)) return;

  const rail = document.createElement('aside');
  rail.className = 'v284-release-rail';
  rail.dataset.releaseKind = release.kind;
  rail.dataset.releaseId = release.id;
  rail.dataset.ariaCn = release.labelCn;
  rail.dataset.ariaEn = release.labelEn;

  const link = document.createElement('a');
  link.className = 'v284-release-rail__link';
  link.href = release.href;

  const meta = document.createElement('span');
  meta.className = 'v284-release-rail__meta';

  const label = document.createElement('span');
  label.dataset.navCn = release.labelCn;
  label.dataset.navEn = release.labelEn;

  const time = document.createElement('time');
  time.dateTime = release.publishAt;
  time.textContent = release.publishAt.slice(0, 10).replaceAll('-', '.');
  meta.append(label, time);

  const title = document.createElement('strong');
  title.className = 'v284-release-rail__title';
  title.dataset.navCn = release.titleCn;
  title.dataset.navEn = release.titleEn;

  const action = document.createElement('span');
  action.className = 'v284-release-rail__action';

  const actionText = document.createElement('span');
  actionText.dataset.navCn = release.actionCn;
  actionText.dataset.navEn = release.actionEn;

  const arrow = document.createElement('i');
  arrow.className = 'v284-release-rail__arrow';
  arrow.setAttribute('aria-hidden', 'true');
  arrow.textContent = '↗';
  action.append(actionText, arrow);

  function syncLanguage() {
    const language = document.documentElement.lang === 'en' ? 'en' : 'cn';
    rail.setAttribute('aria-label', language === 'en' ? release.labelEn : release.labelCn);
    label.textContent = language === 'en' ? release.labelEn : release.labelCn;
    title.textContent = language === 'en' ? release.titleEn : release.titleCn;
    actionText.textContent = language === 'en' ? release.actionEn : release.actionCn;
  }

  link.append(meta, title, action);
  rail.append(link);
  document.body.dataset.v284ReleasePreview = 'true';
  document.body.dataset.homeReleaseEnabled = 'true';
  hero.append(rail);
  syncLanguage();

  new MutationObserver(syncLanguage).observe(document.documentElement, {
    attributes: true,
    attributeFilter: ['lang']
  });
})();