/**
 * RFC 9110 weak comparison for a GET/HEAD `If-None-Match` precondition, shared by the host-owned
 * asset routes that answer `304` against a strong validator they computed from their own bytes.
 */
export function etagMatches(headerValue: string | undefined, etag: string): boolean {
  if (headerValue === undefined) {
    return false;
  }
  if (headerValue.trim() === "*") {
    return true;
  }
  return headerValue.split(",").some((candidate) => {
    const value = candidate.trim();
    return (value.startsWith("W/") ? value.slice(2) : value) === etag;
  });
}