import { Semaphore } from "async-mutex";

import  { type LocaleData } from "./global_locale";
import { isLocaleLoaded, setLocale } from "./global_locale";

const localeLoadingSemaphore = new Semaphore(1);

export async function loadLocale() {
   
  const locale = document.querySelector<HTMLElement>("html")?.lang || "en";

  // We use a Semaphore here so only one thing can try to load the locales at
  // the same time. If one tries to do it while its in progress, it will wait
  // for the initial load to finish before it is resumed (and will see that locale
  // data is already loaded)
  await localeLoadingSemaphore.runExclusive(async () => {
    // if the locale is already set, then do nothing
    if (isLocaleLoaded()) {
      return;
    }

    const localeData = (await import(
      /* webpackMode: "lazy" */
      /* webpackChunkName: "locales/vanilla/[request]" */
      /* webpackInclude: /\.json$/ */
      /* webpackPreload: true */
      `mastodon/locales/${locale}.json`,
    )) as LocaleData["messages"];

    setLocale({ messages: localeData, locale });
  });
}