// src/i18n/utils.ts
import { ui, defaultLang, languages } from './ui';

export type Lang = keyof typeof languages;
export type UiKeys = keyof typeof ui[typeof defaultLang];



export function useTranslations(lang: Lang | undefined) {
  const currentLang = lang || defaultLang;
  return function t(key: UiKeys, ...args: any[]): string {
    let translation: string = ui[currentLang][key] || ui[defaultLang][key];
    if (args.length > 0) {
      args.forEach((arg, index) => {
        translation = translation.replace(`{${index}}`, arg);
      });
    }
    return translation;
  };
}

export function getLocalizedPath(path: string, lang: Lang | undefined): string {
  const currentLang = lang || defaultLang;
  const basePath = import.meta.env.BASE_URL === '/' ? '' : import.meta.env.BASE_URL;

  // Astro's i18n routing handles prefixing automatically based on astro.config.mjs settings.
  // We just need to ensure the path is correctly formed relative to the base.
  // If a language is explicitly provided and it's not the default, 
  // and prefixDefaultLocale is false (meaning default lang has no prefix),
  // we might need to add it. However, Astro typically handles this.
  // For now, let's assume Astro's routing takes care of the prefix.
  // This function might become simpler or even unnecessary depending on how LanguageSwitcher is used.

  let newPath = path;
  // Ensure path starts with a slash if it's not an external URL
  if (!newPath.startsWith('/') && !newPath.match(/^https?:\/\//)) {
    newPath = `/${newPath}`;
  }

  // If prefixDefaultLocale is false (default in our config) and currentLang is not defaultLang,
  // Astro will expect /zh/path. If currentLang is defaultLang, it expects /path.
  // If prefixDefaultLocale is true, all locales get a prefix: /en/path, /zh/path.

  // Given our astro.config.mjs: prefixDefaultLocale: false
  // If lang is 'zh', the path should be /zh/your-path
  // If lang is 'en' (default), the path should be /your-path
  // Astro's <a href> or Astro.redirect should handle this correctly when given a root-relative path.
  // This function's main job is to ensure the base path and the target path are combined correctly.

  const fullPath = `${basePath}${newPath}`;
  return fullPath.replace(/\/\/+/g, '/'); // Clean up any double slashes
}