import ElementUI from 'element-ui';
// 语言选项缓存的key
const CACHE_KEY = "local";
 
// 缓存语言类型
const SET_CACHE_LANGUAGE = (language) => {
  localStorage.setItem(CACHE_KEY, language);
};
 
// 读取语言类型
const GET_CACHE_LANGUAGE = () => {
  return localStorage.getItem(CACHE_KEY);
};
 
// 默认语言选项
export const DEFAULT_LANGUAGE = "zh";
 
// 可选语言列表
export let languageOption = [
  { label: "中文", value: "zh" },
  { label: "英文", value: "en" },
];
 
/**
 * @desc 获取网站语言
 * @return {string} 语言类型
 */
export const getLanguage = () => {
  const { language } = navigator;
  const lang = language && language.split("-")[0];
 
  const isValidLanguage = languageOption.some((s) => s.value === lang);
  const browserLanguage = isValidLanguage ? lang : DEFAULT_LANGUAGE;
 
  // TODO: 已设置vue-i18n默认值和兜底都是zh 所以这里没有缓存zh 可自行按需求缓存
  return GET_CACHE_LANGUAGE() || browserLanguage;
};
 
/**
 * @param {string} language - 语言类型: en、ch
 * @param {object} vm - 当前vue实例指向
 * @desc 改变网站语言
 * @example
 * ```js
 *  changeLanguage("en",this);
 * ```
 */
export const changeLanguage = (language, vm) => {
  if (!vm) {
    throw "缺少 vm 实例入参";
  }
  vm.$i18n.locale = language;
  SET_CACHE_LANGUAGE(language);
};