Function parseNav

packages/foliate-js/epub.js:349–383

(doc, resolve = (f) => f)

};

const parseNav = (doc, resolve = (f) => f) => {
  const { $, $$, $$$ } = childGetter(doc, NS.XHTML);
  const resolveHref = (href) => (href ? decodeURI(resolve(href)) : null);
  const parseLI = (getType) => ($li) => {
    const $a = $($li, "a") ?? $($li, "span");
    const $ol = $($li, "ol");
    const href = resolveHref($a?.getAttribute("href"));
    const label = getElementText($a) || $a?.getAttribute("title");
    // TODO: get and concat alt/title texts in content
    const result = { label, href, subitems: parseOL($ol) };
    if (getType) result.type = $a?.getAttributeNS(NS.EPUB, "type")?.split(/\s/);
    return result;
  };
  const parseOL = ($ol, getType) => ($ol ? $$($ol, "li").map(parseLI(getType)) : null);
  const parseNav = ($nav, getType) => parseOL($($nav, "ol"), getType);

  const $$nav = $$$(doc, "nav");
  let toc = null,
    pageList = null,
    landmarks = null,
    others = [];
  for (const $nav of $$nav) {
    const type = $nav.getAttributeNS(NS.EPUB, "type")?.split(/\s/) ?? [];
    if (type.includes("toc")) toc ??= parseNav($nav);
    else if (type.includes("page-list")) pageList ??= parseNav($nav);
    else if (type.includes("landmarks")) landmarks ??= parseNav($nav, true);
    else
      others.push({
        label: getElementText($nav.firstElementChild),
        type,
        list: parseNav($nav),
      });
  }
  return { toc, pageList, landmarks, others };
};

const parseNCX = (doc, resolve = (f) => f) => {
  const { $, $$ } = childGetter(doc, NS.NCX);