/** UTM parameters captured from the storefront URL at checkout start. */

export interface UtmParams {
  utm_source?: string;
  utm_medium?: string;
  utm_campaign?: string;
}

const UTM_KEYS = ['utm_source', 'utm_medium', 'utm_campaign'] as const;

/** Read UTM params from the current page URL (web). Returns {} on native or SSR. */
export function captureUtmFromUrl(href?: string): UtmParams {
  try {
    const url = new URL(href ?? (typeof window !== 'undefined' ? window.location.href : ''));
    const out: UtmParams = {};
    for (const key of UTM_KEYS) {
      const v = url.searchParams.get(key);
      if (v) out[key] = v.slice(0, 256);
    }
    return out;
  } catch {
    return {};
  }
}

/** True when at least one UTM field is set. */
export function hasUtmParams(utm: UtmParams): boolean {
  return Boolean(utm.utm_source || utm.utm_medium || utm.utm_campaign);
}