import { createI18n } from "vue-i18n";
import { localeMap, type LocaleType } from "./config";
import { setHtmlPageLang, setLoadLocalePool } from "./helper";
import { useLocaleStoreWithOut } from "../store/modules/locale";
import enUS from "./lang/en_US";
import zhCN from "./lang/zh_CN";

/** Vite/ESM：default 导出即 { message, ... }；部分 webpack 链路上可能再包一层 .default，两处都兼容 */
function getLocaleMessages(mod: typeof zhCN | typeof enUS) {
  type Bundle = { message?: Record<string, unknown> };
  const withMaybeDefault = mod as Bundle & { default?: Bundle };
  const bundle = withMaybeDefault.default ?? withMaybeDefault;
  return bundle.message ?? {};
}

/**
 * 获取宿主（基座）语言。
 * qiankun 微前端场景下，基座会在 window 上注入全局 LtConfig.locale（"zh"/"en" 等），
 * 组件库的语言必须跟随基座；若只读自己 storage 里的 LOCALE__（默认 zh_CN），
 * 宿主切英文后"序号"等库内部文案会仍停留在中文。
 */
function getHostLocale(): LocaleType | undefined {
  const hostLocale = (globalThis as any)?.LtConfig?.locale;
  if (typeof hostLocale == "string" && hostLocale) {
    const lower = hostLocale.toLowerCase();
    if (lower.startsWith("en")) return localeMap.en_US;
    if (lower.startsWith("zh")) return localeMap.zh_CN;
  }
  return undefined;
}

function createI18nOptions() {
  const localeStore = useLocaleStoreWithOut();
  const locale = getHostLocale() ?? localeStore.getLocale;
  //与宿主语言对齐后写回本地存储，保证库内其他读取 locale 的模块（antd 包装语言等）一致
  if (localeStore.getLocale !== locale) {
    localeStore.setLocale(locale);
  }
  const defaultLocal = locale == "zh_CN" ? zhCN : enUS;
  const message = getLocaleMessages(defaultLocal);

  setHtmlPageLang(locale);
  setLoadLocalePool((loadLocalePool) => {
    loadLocalePool.push(locale);
  });

  return {
    locale,
    legacy: false,
    fallbackLocale: localeMap.zh_CN, // set fallback locale
    messages: {
      [locale]: message as { [key: string]: string },
    },
    globalInjection: true,
    silentTranslationWarn: true, // true - warning off
    missingWarn: false,
    silentFallbackWarn: true,
  };
}

const options = createI18nOptions();
export const i18n = createI18n(options);

/**
 * 运行时把库内 i18n 切到目标语言（含语言包装载与本地存储同步）。
 * 库的 i18n 是独立实例，宿主通过 qiankun onGlobalStateChange 免刷新切语言时，
 * 必须由这里同步，否则"序号"等库内部文案不会跟随变化。
 */
function syncI18nLocale(locale: LocaleType) {
  const local = locale == "zh_CN" ? zhCN : enUS;
  i18n.global.setLocaleMessage(locale, getLocaleMessages(local) as any);
  (i18n.global.locale as any).value = locale;
  useLocaleStoreWithOut().setLocale(locale);
}

//监听基座语言变化（qiankun 免刷新切换场景：基座更新全局 LtConfig.locale）
let lastHostLocale = (globalThis as any)?.LtConfig?.locale;
setInterval(() => {
  const hostLocale = (globalThis as any)?.LtConfig?.locale;
  if (typeof hostLocale == "string" && hostLocale && hostLocale !== lastHostLocale) {
    lastHostLocale = hostLocale;
    const target = getHostLocale();
    if (target && (i18n.global.locale as any).value !== target) {
      syncI18nLocale(target);
    }
  }
}, 1000);

// setup i18n instance with global
// export function setupI18n(app: App) {
//   app.use(i18n);
// }