/**
 * Build a `mailto:` URL from an address, subject, and body.
 * Subject and body are URL-encoded so the visitor's mail client
 * opens pre-filled with the submitted values.
 *
 * @param {{to?: string, subject?: string, body?: string}} options
 * @returns {string}
 */
export function buildMailtoUrl({ to = "", subject = "", body = "" } = {}) {
  const params = new URLSearchParams();
  if (subject) params.set("subject", subject);
  if (body) params.set("body", body);
  const query = params.toString();
  return query ? `mailto:${to}?${query}` : `mailto:${to}`;
}