// hooks/useLanguage.tsx
'use client';

import { useState, useEffect } from 'react';
import { useRouter, usePathname } from 'next/navigation';
import { content, LanguageType, ContentType } from '../lib/content';

export function useLanguage(
  initialLang: string
): {
  currentLang: LanguageType;
  setCurrentLang: (newLang: LanguageType) => void;
  createLocalizedPath: (path: string) => string;
  currentContent: ContentType;
} {
  const router   = useRouter();
  const pathname = usePathname();

  const SUPPORTED = ['en', 'zh-CN', 'zh-TW'] as const;
  const normalized = (SUPPORTED.includes(initialLang as any)
    ? initialLang
    : 'en') as LanguageType;

  const [currentLang, setLang] = useState<LanguageType>(normalized);
  useEffect(() => {
    setLang(normalized);
  }, [normalized]);

  const setCurrentLang = (newLang: LanguageType) => {
    const parts = pathname.split('/').filter(Boolean);
    const rest  = parts.slice(1).join('/');
    router.push(`/${newLang}${rest ? '/' + rest : ''}`);
  };

  const createLocalizedPath = (path: string) =>
    path.startsWith('/')
      ? `/${currentLang}${path}`
      : `/${currentLang}/${path}`;

  // —— 关键：从 content 里取出当前语言的数据 —— 
  const currentContent: ContentType = content[currentLang];

  return {
    currentLang,
    setCurrentLang,
    createLocalizedPath,
    currentContent,
  };
}