// Text utilities kept from forthena's lib/llm.js (this site has NO LLM layer —
// the ranking is deterministic, see lib/feed.js). The file keeps the llm.js
// module name so the crawl/article imports don't churn.

export function sanitize(s) {
  return String(s || "")
    .replace(/<[^>]*>/g, " ")
    .replace(/\s+/g, " ")
    .trim();
}

// First image an RSS item exposes, in descending order of reliability.
export function extractImage(item, feed) {
  const cands = [];
  const enc = item.enclosure;
  if (enc && enc.url && (/image/i.test(enc.type || "") || /\.(jpe?g|png|webp|gif|avif)/i.test(enc.url))) cands.push(enc.url);
  for (const key of ["mediaContent", "mediaThumbnail", "media:content", "media:thumbnail"]) {
    const v = item[key];
    const list = Array.isArray(v) ? v : v ? [v] : [];
    for (const m of list) {
      const u = (m && (m["$"]?.url || m.url || m.$?.url)) || null;
      if (u) cands.push(u);
    }
  }
  const itn = item.itunesImage || item.image;
  if (itn) cands.push((itn["$"] && itn["$"].href) || itn.href || (typeof itn === "string" ? itn : null));
  const html = [item["content:encoded"], item.content, item.contentSnippet, item.summary]
    .filter(Boolean)
    .join(" ");
  const m = /<img[^>]+src=["']([^"']+)["']/i.exec(html);
  if (m) cands.push(m[1]);
  const fi = feed && feed.image && (feed.image.url || feed.image.$?.url);
  if (fi) cands.push(fi);
  for (const u of cands) {
    const s = String(u || "").trim();
    if (!/^https?:\/\//i.test(s)) continue;
    if (/1x1|spacer|pixel\.gif|blank\.|logo-|sprite/i.test(s)) continue;
    return s.slice(0, 500);
  }
  return null;
}