Function excerpt

web/lib/search/highlighter.ts:28–53

(text: string, query: string, maxLength = 160)

 * Returns a short excerpt (up to maxLength chars) centred around the first match.
 */
export function excerpt(text: string, query: string, maxLength = 160): string {
  if (!query.trim()) return text.slice(0, maxLength);

  const terms = tokenize(query);
  if (terms.length === 0) return text.slice(0, maxLength);

  const lowerText = text.toLowerCase();
  let matchIndex = -1;

  for (const term of terms) {
    const idx = lowerText.indexOf(term.toLowerCase());
    if (idx !== -1) {
      matchIndex = idx;
      break;
    }
  }

  if (matchIndex === -1) return text.slice(0, maxLength);

  const half = Math.floor(maxLength / 2);
  const start = Math.max(0, matchIndex - half);
  const end = Math.min(text.length, start + maxLength);
  const slice = text.slice(start, end);

  return (start > 0 ? "…" : "") + slice + (end < text.length ? "…" : "");
}

/** Tokenise a query string into non-empty lowercase words. */
export function tokenize(query: string): string[] {