wallet-core/packages/taler-wallet-webextension/src/hooks/useLang.ts

/*
 This file is part of GNU Taler
 (C) 2021 Taler Systems S.A.

 GNU Taler is free software; you can redistribute it and/or modify it under the
 terms of the GNU General Public License as published by the Free Software
 Foundation; either version 3, or (at your option) any later version.

 GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
 A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

 You should have received a copy of the GNU General Public License along with
 GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
 */

import { useNotNullLocalStorage } from './useLocalStorage';

export function useLang(initial?: string): [string, (s:string) => void] {
  const browserLang: string | undefined = typeof window !== "undefined" ? navigator.language || (navigator as any).userLanguage : undefined;
  const defaultLang = (browserLang || initial || 'en').substring(0, 2)
  return useNotNullLocalStorage('lang-preference', defaultLang)
}