import i18n from "i18next";
import { initReactI18next } from "react-i18next";
import en from "./locales/en.json";
import de from "./locales/de.json";

export const SUPPORTED_LANGUAGES = [
  { code: "en", label: "English" },
  { code: "de", label: "Deutsch" },
] as const;

export type LanguageCode = (typeof SUPPORTED_LANGUAGES)[number]["code"];

const STORAGE_KEY = "toolr-language";

export function getStoredLanguage(): LanguageCode {
  if (typeof window === "undefined") return "en";
  const stored = window.localStorage.getItem(STORAGE_KEY);
  if (stored === "en" || stored === "de") return stored;
  const nav = window.navigator.language?.toLowerCase() ?? "";
  return nav.startsWith("de") ? "de" : "en";
}

export function setStoredLanguage(lang: LanguageCode) {
  window.localStorage.setItem(STORAGE_KEY, lang);
}

void i18n.use(initReactI18next).init({
  resources: {
    en: { translation: en },
    de: { translation: de },
  },
  lng: getStoredLanguage(),
  fallbackLng: "en",
  interpolation: { escapeValue: false },
});

export default i18n;