/**
 * The three languages the showcase speaks, in the order the switcher draws them.
 *
 * `az` is the default because the kit documents a Baku bank's design system and
 * CBAR's own site opens in Azerbaijani. `useParam` drops a value equal to its
 * fallback from the hash, so the default language costs the URL nothing.
 */
export const LANGS = ['az', 'ru', 'en'] as const;

export type Lang = (typeof LANGS)[number];

export const DEFAULT_LANG: Lang = 'az';

/** Short labels for the switcher — never translated, they name themselves. */
export const LANG_LABELS: Record<Lang, string> = {
  az: 'AZ',
  ru: 'RU',
  en: 'EN',
};

/**
 * The hash is user-editable, so `?lang=zz` has to fall back rather than index a
 * catalogue with `undefined`.
 */
export function isLang(value: string): value is Lang {
  return (LANGS as readonly string[]).includes(value);
}