import React, { useState, useEffect, useCallback } from 'react';
import { Link, useLocation } from 'react-router-dom';
import './Header.css';

const MENU = [
  {
    id: 'company', label: '회사소개',
    children: [
      { label: 'CEO 인사말',  path: '/company/greeting' },
      { label: '연혁',        path: '/company/history' },
      { label: '조직도',      path: '/company/organization' },
      { label: 'CI 소개',     path: '/company/ci' },
      { label: '오시는 길',   path: '/company/location' },
    ]
  },
  {
    id: 'solution', label: '솔루션',
    children: [
      { label: 'GUARDiA ITSM', path: '/solution/guardia', badge: 'NEW' },
      { label: 'ERP',           path: '/solution/erp' },
      { label: 'CRM',           path: '/solution/crm' },
      { label: 'BI',            path: '/solution/bi' },
    ]
  },
  {
    id: 'business', label: '사업실적',
    children: [
      { label: '구축 레퍼런스', path: '/business/reference' },
      { label: '파트너',        path: '/business/partner' },
    ]
  },
  {
    id: 'support', label: '고객지원',
    children: [
      { label: '공지사항', path: '/support/notice' },
      { label: 'FAQ',      path: '/support/faq' },
      { label: '카탈로그', path: '/support/catalog' },
      { label: '문의하기', path: '/support/contact' },
    ]
  },
  {
    id: 'recruit', label: '채용',
    children: [
      { label: '채용공고', path: '/recruit/jobs' },
      { label: '복리후생', path: '/recruit/welfare' },
      { label: '지원하기', path: '/recruit/apply' },
    ]
  },
  {
    id: 'news', label: '뉴스',
    children: [
      { label: '뉴스룸',      path: '/news/newsroom' },
      { label: '기술 블로그', path: '/news/blog' },
    ]
  },
];

export default function Header() {
  const [scrolled,    setScrolled]    = useState(false);
  const [activeMenu,  setActiveMenu]  = useState(null);
  const [mobileOpen,  setMobileOpen]  = useState(false);
  const location = useLocation();

  useEffect(() => {
    const onScroll = () => setScrolled(window.scrollY > 60);
    window.addEventListener('scroll', onScroll, { passive: true });
    return () => window.removeEventListener('scroll', onScroll);
  }, []);

  useEffect(() => {
    setMobileOpen(false);
    setActiveMenu(null);
  }, [location]);

  const isActive = (menu) =>
    menu.children?.some(c => location.pathname.startsWith(c.path));

  return (
    <>
      {/* 접근성 스킵 링크 */}
      <a href="#main-content" className="skip-link">본문 바로가기</a>

      <header className={`header ${scrolled ? 'scrolled' : ''} ${mobileOpen ? 'mobile-open' : ''}`}
              role="banner">
        <div className="header-inner container">
          {/* 로고 */}
          <Link to="/" className="logo" aria-label="(주)지오정보기술 홈으로">
            <img src="/logo.png" alt="(주)지오정보기술 로고" height="40"
                 onError={e => { e.target.style.display='none'; e.target.nextSibling.style.display='flex'; }} />
            <span className="logo-text" style={{display:'none'}}>
              <strong>Zio</strong>Info
            </span>
          </Link>

          {/* 데스크톱 메뉴 */}
          <nav className="nav-desktop" role="navigation" aria-label="주요 메뉴">
            {MENU.map(menu => (
              <div key={menu.id}
                   className={`nav-item ${isActive(menu) ? 'active' : ''}`}
                   onMouseEnter={() => setActiveMenu(menu.id)}
                   onMouseLeave={() => setActiveMenu(null)}>
                <button className="nav-trigger" aria-haspopup="true"
                        aria-expanded={activeMenu === menu.id}>
                  {menu.label}
                </button>
                {activeMenu === menu.id && (
                  <div className="dropdown" role="menu">
                    {menu.children.map(child => (
                      <Link key={child.path} to={child.path}
                            className={`dropdown-item ${location.pathname === child.path ? 'current' : ''}`}
                            role="menuitem">
                        {child.label}
                        {child.badge && <span className="badge badge-new">{child.badge}</span>}
                      </Link>
                    ))}
                  </div>
                )}
              </div>
            ))}
          </nav>

          {/* 문의 버튼 */}
          <Link to="/support/contact" className="btn btn-primary btn-sm header-cta">
            문의하기
          </Link>

          {/* 햄버거 (모바일) */}
          <button className="hamburger" aria-label="모바일 메뉴"
                  aria-expanded={mobileOpen}
                  onClick={() => setMobileOpen(v => !v)}>
            <span/><span/><span/>
          </button>
        </div>

        {/* 모바일 메뉴 */}
        {mobileOpen && (
          <nav className="nav-mobile" role="navigation" aria-label="모바일 메뉴">
            {MENU.map(menu => (
              <details key={menu.id} className="mobile-group">
                <summary className="mobile-group-header">{menu.label}</summary>
                <div className="mobile-children">
                  {menu.children.map(child => (
                    <Link key={child.path} to={child.path} className="mobile-child">
                      {child.label}
                      {child.badge && <span className="badge badge-new">{child.badge}</span>}
                    </Link>
                  ))}
                </div>
              </details>
            ))}
            <Link to="/support/contact" className="btn btn-primary" style={{margin:'16px'}}>
              문의하기
            </Link>
          </nav>
        )}
      </header>
    </>
  );
}