/*
 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/>
 */

/**
*
* @author Sebastian Javier Marchano (sebasjm)
*/

import { createContext, h, VNode } from 'preact'
import { useContext, useEffect } from 'preact/hooks'
import { useLang } from '../hooks/useLang'
//@ts-ignore: type declaration
import * as jedLib from "jed";
import { strings } from "../i18n/strings";
import { setupI18n } from '@gnu-taler/taler-util';

interface Type {
  lang: string;
  changeLanguage: (l: string) => void;
}
const initial = {
  lang: 'en',
  changeLanguage: () => {
    // do not change anything
  }
}
const Context = createContext<Type>(initial)

interface Props {
  initial?: string,
  children: any,
  forceLang?: string
}

//we use forceLang when we don't want to use the saved state, but sone forced 
//runtime lang predefined lang 
export const TranslationProvider = ({ initial, children, forceLang }: Props): VNode => {
  const [lang, changeLanguage] = useLang(initial)
  useEffect(() => {
    if (forceLang) {
      changeLanguage(forceLang)
    }
  })
  useEffect(()=> {
    setupI18n(lang, strings)
  },[lang])
  if (forceLang) {
    setupI18n(forceLang, strings)
  } else {
    setupI18n(lang, strings)    
  }
  return h(Context.Provider, { value: { lang, changeLanguage }, children });
}

export const useTranslationContext = (): Type => useContext(Context);