/* eslint-disable @next/next/no-img-element */
'use client';

import { useEffect, useMemo, useRef, useState } from 'react';
import { useRouter } from 'next/navigation';
import Link from 'next/link';
import MainLogoSvg from './svgs/mainlogosvg';
import apiService from './lib/apiService';
import type { Notice } from './admin/notices/mockData';

interface Subject {
  id: string | number;
  title: string;
  imageKey?: string;
  instructor?: string;
}

interface CourseCard {
  id: string | number;
  title: string;
  meta: string;
  image: string;
}

export default function Home() {
  const router = useRouter();
  const containerRef = useRef<HTMLDivElement | null>(null);
  const [currentIndex, setCurrentIndex] = useState(0);
  const [userName, setUserName] = useState<string>('');
  const [subjects, setSubjects] = useState<Subject[]>([]);
  const [courseCards, setCourseCards] = useState<CourseCard[]>([]);
  const [loadingSubjects, setLoadingSubjects] = useState(true);
  const [totalSubjectsCount, setTotalSubjectsCount] = useState(0);
  const [notices, setNotices] = useState<Notice[]>([]);
  const [loadingNotices, setLoadingNotices] = useState(true);

  // NOTE: 실제 이미지 자산 연결 시 해당 src를 교체하세요.
  const slides = useMemo(
    () => [
      {
        id: 1,
        title: '시스템 점검 안내',
        description: '11월 10일 새벽 2시~4시 시스템 점검이 진행됩니다.',
        imageSrc: 'https://picsum.photos/seed/xrlms-slide1/1600/900',
      },
      {
        id: 2,
        title: '신규 과정 오픈',
        description: '최신 커리큘럼으로 업스킬링하세요.',
        imageSrc: 'https://picsum.photos/seed/xrlms-slide2/1600/900',
      },
      {
        id: 3,
        title: '수강 이벤트',
        description: '이번 달 수강 혜택을 확인해보세요.',
        imageSrc: 'https://picsum.photos/seed/xrlms-slide3/1600/900',
      },
    ],
    []
  );

  // 사용자 정보 가져오기
  useEffect(() => {
    let isMounted = true;

    async function fetchUserInfo() {
      try {
        const localStorageToken = localStorage.getItem('token');
        const cookieToken = document.cookie
          .split('; ')
          .find(row => row.startsWith('token='))
          ?.split('=')[1];
        
        const token = localStorageToken || cookieToken;
        
        if (!token) {
          return;
        }

        const response = await apiService.getCurrentUser();

        if (response.status !== 200) {
          return;
        }

        const data = response.data;
        
        if (isMounted) {
          // 사용자 권한 확인
          const userRole = data.role || data.userRole;
          if (userRole === 'ADMIN' || userRole === 'admin') {
            // admin 권한이면 /admin/id로 리다이렉트
            router.push('/admin/id');
            return;
          }
          
          if (data.name) {
            setUserName(data.name);
          }
        }
      } catch (error) {
        console.error('사용자 정보 조회 오류:', error);
      }
    }

    fetchUserInfo();

    return () => {
      isMounted = false;
    };
  }, []);

  // 과목 리스트 가져오기
  useEffect(() => {
    let isMounted = true;

    async function fetchSubjects() {
      try {
        setLoadingSubjects(true);
        const response = await apiService.getSubjects();

        if (response.status !== 200 || !response.data) {
          return;
        }

        // 응답 데이터 구조 확인 및 배열 추출
        let subjectsData: any[] = [];
        let totalCount = 0;

        if (Array.isArray(response.data)) {
          subjectsData = response.data;
          totalCount = response.data.length;
        } else if (response.data && typeof response.data === 'object') {
          // 다양한 응답 구조 처리
          subjectsData = response.data.items || 
                        response.data.courses || 
                        response.data.data || 
                        response.data.list || 
                        response.data.subjects || 
                        response.data.subjectList || 
                        [];
          
          // 전체 개수는 total, totalCount, count 등의 필드에서 가져오거나 배열 길이 사용
          totalCount = response.data.total !== undefined ? response.data.total :
                      response.data.totalCount !== undefined ? response.data.totalCount :
                      response.data.count !== undefined ? response.data.count :
                      subjectsData.length;
        }

        console.log('과목 리스트 응답:', response.data);
        console.log('추출된 과목 데이터:', subjectsData);
        console.log('전체 과목 개수:', totalCount);
        
        if (!isMounted) return;

        // 전체 과목 개수 저장
        setTotalSubjectsCount(totalCount);

        // 상위 10개만 가져오기
        const top10Subjects = subjectsData.slice(0, 10);
        setSubjects(top10Subjects);

        // 각 과목의 이미지 다운로드
        const courseCardsWithImages = await Promise.all(
          top10Subjects.map(async (subject: Subject) => {
            let imageUrl = 'https://picsum.photos/seed/xrlms-fallback-card/1200/800';
            
            if (subject.imageKey) {
              try {
                const fileUrl = await apiService.getFile(subject.imageKey);
                if (fileUrl) {
                  imageUrl = fileUrl;
                }
              } catch (error) {
                console.error(`이미지 다운로드 실패 (과목 ID: ${subject.id}):`, error);
              }
            }

            return {
              id: subject.id,
              title: subject.title || '',
              meta: subject.instructor ? `강사: ${subject.instructor}` : 'VOD • 온라인',
              image: imageUrl,
            };
          })
        );

        if (isMounted) {
          setCourseCards(courseCardsWithImages);
        }
      } catch (error) {
        console.error('과목 리스트 조회 오류:', error);
      } finally {
        if (isMounted) {
          setLoadingSubjects(false);
        }
      }
    }

    fetchSubjects();

    return () => {
      isMounted = false;
    };
  }, []);

  // 공지사항 리스트 가져오기
  useEffect(() => {
    let isMounted = true;

    async function fetchNotices() {
      try {
        setLoadingNotices(true);
        const response = await apiService.getNotices();

        if (response.status !== 200 || !response.data) {
          return;
        }

        // API 응답이 배열이 아닌 경우 처리 (예: { items: [...] } 형태)
        let noticesArray: any[] = [];
        if (Array.isArray(response.data)) {
          noticesArray = response.data;
        } else if (response.data && typeof response.data === 'object') {
          noticesArray = response.data.items || response.data.notices || response.data.data || response.data.list || [];
        }

        // 날짜를 yyyy-mm-dd 형식으로 포맷팅
        const formatDate = (dateString: string): string => {
          if (!dateString) return '';
          
          try {
            const date = new Date(dateString);
            if (isNaN(date.getTime())) {
              // 이미 yyyy-mm-dd 형식인 경우 그대로 반환
              if (/^\d{4}-\d{2}-\d{2}$/.test(dateString)) {
                return dateString;
              }
              return dateString;
            }
            
            const year = date.getFullYear();
            const month = String(date.getMonth() + 1).padStart(2, '0');
            const day = String(date.getDate()).padStart(2, '0');
            return `${year}-${month}-${day}`;
          } catch {
            return dateString;
          }
        };

        // API 응답 데이터를 Notice 형식으로 변환
        const transformedNotices: Notice[] = noticesArray.map((notice: any) => ({
          id: notice.id || notice.noticeId || 0,
          title: notice.title || '',
          date: formatDate(notice.date || notice.createdAt || notice.createdDate || new Date().toISOString().split('T')[0]),
          views: notice.views || notice.viewCount || 0,
          writer: notice.writer || notice.author || notice.createdBy || '관리자',
          content: notice.content ? (Array.isArray(notice.content) ? notice.content : [notice.content]) : undefined,
          hasAttachment: notice.hasAttachment || notice.attachment || false,
        }));

        if (!isMounted) return;

        // 날짜 내림차순 정렬 (최신 날짜가 먼저)
        const sortedNotices = [...transformedNotices].sort((a, b) => b.date.localeCompare(a.date));
        setNotices(sortedNotices);
      } catch (error) {
        console.error('공지사항 리스트 조회 오류:', error);
      } finally {
        if (isMounted) {
          setLoadingNotices(false);
        }
      }
    }

    fetchNotices();

    return () => {
      isMounted = false;
    };
  }, []);

  useEffect(() => {
    const containerEl = containerRef.current;
    if (!containerEl) return;

    const handleScroll = () => {
      const width = containerEl.clientWidth;
      const index = Math.round(containerEl.scrollLeft / Math.max(width, 1));
      setCurrentIndex(index);
    };

    containerEl.addEventListener('scroll', handleScroll, { passive: true });
    return () => {
      containerEl.removeEventListener('scroll', handleScroll);
    };
  }, []);

  const scrollToIndex = (index: number) => {
    const containerEl = containerRef.current;
    if (!containerEl) return;
    const clamped = Math.max(0, Math.min(index, slides.length - 1));
    const width = containerEl.clientWidth;
    containerEl.scrollTo({ left: clamped * width, behavior: 'smooth' });
  };

  const handlePrev = () => scrollToIndex(currentIndex - 1);
  const handleNext = () => scrollToIndex(currentIndex + 1);

  return (
    <div className="w-full min-h-screen flex flex-col bg-white">
      <main className="flex-1">
        {/* 메인 컨테이너 */}
        <div className="w-full flex justify-center">
          <div className="w-full max-w-[1376px] px-3 py-6">
            {/* 배너 + 사이드 */}
            <div className="flex gap-8">
              {/* 배너 */}
              <section className="flex-none w-[944px]" aria-label="홈 상단 배너">
                <div className="relative">
                  <div
                    ref={containerRef}
                    className="flex overflow-x-hidden overscroll-none overflow-y-hidden overscroll-y-none snap-x snap-mandatory scroll-smooth rounded-[12px] bg-[#F1F3F5]"
                  >

                    {slides.map((slide) => (
                      <div key={slide.id} className="flex-none w-full h-[510px] relative snap-start overflow-hidden">
                      <img
                        alt={slide.title}
                        src={slide.imageSrc}
                        className="w-full h-full object-cover block"
                        onError={(e) => {
                          const t = e.currentTarget as HTMLImageElement;
                          if (!t.src.includes('picsum.photos')) t.src = 'https://picsum.photos/seed/xrlms-fallback-slide/1600/900';
                        }}
                      />
                        <div className="absolute left-0 right-0 bottom-0 h-[198px] bg-linear-to-b from-transparent to-black/50" />
                        <div className="absolute left-12 bottom-8 text-white">
                          <div className="font-bold text-[32px] tracking-[-0.32px] leading-normal mb-1.5">{slide.title}</div>
                          <div className="font-bold text-[24px] tracking-[-0.24px] leading-normal opacity-95">
                            {slide.description}
                          </div>
                        </div>
                      </div>
                    ))}
                  </div>

                  {/* 좌/우 내비게이션 버튼 */}
                  <button
                    type="button"
                    onClick={handlePrev}
                    aria-label="이전 배너"
                    disabled={currentIndex <= 0}
                    className="absolute left-4 top-1/2 -translate-y-1/2 size-12 rounded-full bg-white/20 text-white flex items-center justify-center cursor-pointer disabled:opacity-60"
                  >
                    <svg width="24" height="24" viewBox="0 0 24 24" aria-hidden>
                      <path d="M15 6l-6 6 6 6" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round" />
                    </svg>
                  </button>
                  <button
                    type="button"
                    onClick={handleNext}
                    aria-label="다음 배너"
                    disabled={currentIndex >= slides.length - 1}
                    className="absolute right-4 top-1/2 -translate-y-1/2 size-12 rounded-full bg-white/20 text-white flex items-center justify-center cursor-pointer disabled:opacity-60"
                  >
                    <svg width="24" height="24" viewBox="0 0 24 24" aria-hidden>
                      <path d="M9 6l6 6-6 6" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round" />
                    </svg>
                  </button>

                  {/* 인디케이터 */}
                  <div className="absolute left-1/2 bottom-3 -translate-x-1/2 flex items-center gap-2" aria-hidden>
                    {slides.map((_, idx) => (
                      <span key={idx} className={idx === currentIndex ? 'h-2 w-8 rounded-full bg-white' : 'size-2 rounded-full bg-white/50'} />
                    ))}
                  </div>
                </div>
              </section>

              {/* 사이드 패널 (피그마 디자인 적용) */}
              <aside className="flex-none w-[400px]">
                <div className="bg-[#F1F3F5] rounded-[12px] overflow-hidden h-[510px]">
                  {/* 상단 환영 및 통계 (피그마 사이즈/간격 적용) */}
                  <div className="px-8 py-8">
                    <div className="mb-6">
                      <div className="flex items-center gap-2">
                        <span className="text-[18px] font-bold leading-normal text-[#333C47]">
                          {userName ? `${userName}님` : '사용자님'}
                        </span>
                        <span className="text-[18px] font-bold leading-normal text-[#333C47]">환영합니다.</span>
                      </div>
                    </div>
                    <div className="flex items-center justify-center gap-6">
                      {[
                        { label: '수강중', value: 0 },
                        { label: '수강 완료', value: 0 },
                        { label: '문제 제출', value: 0 },
                        { label: '수료증', value: 0 },
                      ].map((s) => (
                        <div key={s.label} className="w-[64px] flex flex-col items-center justify-center gap-2">
                          <div className="size-16 rounded-full bg-white flex items-center justify-center">
                            <div className="text-[20px] font-bold text-[#333C47] leading-none">{s.value}</div>
                          </div>
                          <div className="text-[15px] font-semibold text-[#333C47] leading-none">{s.label}</div>
                        </div>
                      ))}
                    </div>
                  </div>
                  {/* 구분선 (좌우 32px 여백, 1px 라인) */}
                  <div className="h-px bg-[#DEE1E6] mx-8" />
                  {/* 최근 수강 내역 헤더 + 빈 상태 영역 (피그마 텍스트/간격 일치) */}
                  <div className="px-8 pt-[12px] pb-[24px]">
                    <div className="h-[60px] w-full flex items-center justify-between">
                      <div className="text-[18px] font-bold text-[#1B2027]">최근 수강 내역</div>
                      <a href="#" className="flex items-center gap-0.5 text-[14px] font-medium text-[#6C7682] no-underline">
                        전체보기
                        <svg width="16" height="16" viewBox="0 0 24 24" aria-hidden>
                          <path d="M8 5l8 7-8 7" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round" />
                        </svg>
                      </a>
                    </div>
                    <div className="box-border w-full flex items-center justify-center px-[45px] py-[96px]">
                      <p className="m-0 text-[16px] font-medium text-[#6C7682] text-center">최근 수강 내역이 없습니다.</p>
                    </div>
                  </div>
                </div>
              </aside>
            </div>

            {/* 교육 과정 */}
            <section className="mt-8">
              <div className="flex items-center justify-between h-[100px] px-0">
                <div className="flex items-center gap-3">
                  <h2 className="m-0 text-[24px] font-bold leading-normal text-[#1B2027]">교육 과정</h2>
                  <div className="text-[15px] font-medium leading-normal text-[#333C47]">
                    총 <span className="text-[#384FBF]">{totalSubjectsCount}</span>건
                  </div>
                </div>
                <Link
                  href="/course-list"
                  className="flex items-center gap-0.5 text-[14px] font-medium leading-normal text-[#6C7682] no-underline"
                >
                  전체보기
                  <svg width="16" height="16" viewBox="0 0 24 24" aria-hidden>
                    <path
                      d="M8 5l8 7-8 7"
                      fill="none"
                      stroke="currentColor"
                      strokeWidth="2"
                      strokeLinecap="round"
                      strokeLinejoin="round"
                    />
                  </svg>
                </Link>
              </div>

              {loadingSubjects ? (
                <div className="flex items-center justify-center h-[260px]">
                  <p className="text-[16px] font-medium text-[#6C7682]">로딩 중...</p>
                </div>
              ) : (
                <div className="grid grid-cols-5 gap-8">
                  {courseCards.map((c) => (
                    <article 
                      key={c.id} 
                      onClick={() => router.push(`/course-list/${c.id}`)}
                      className="flex flex-col gap-4 h-[260px] cursor-pointer"
                    >
                      <div className="h-[166.4px] overflow-hidden rounded-[8px] flex items-center justify-center bg-[#F1F3F5] hover:shadow-lg transition-shadow">
                        <img
                          alt={c.title}
                          src={c.image}
                          className="h-full w-auto object-contain block"
                          onError={(e) => {
                            const t = e.currentTarget as HTMLImageElement;
                            if (!t.src.includes('picsum.photos')) t.src = 'https://picsum.photos/seed/xrlms-fallback-card/1200/800';
                          }}
                        />
                      </div>
                      <div className="flex flex-col gap-1">
                        <h5 className="m-0 text-[#333C47] font-semibold text-[18px] leading-normal truncate" title={c.title}>
                          {c.title}
                        </h5>
                        <div className="flex items-center gap-1">
                          <svg width="16" height="16" viewBox="0 0 24 24" aria-hidden className="text-[#8C95A1]">
                            <path d="M8 5v14l11-7z" fill="currentColor" />
                          </svg>
                          <p className="m-0 text-[#8C95A1] text-[13px] font-medium leading-[1.4]">{c.meta}</p>
                        </div>
                      </div>
                    </article>
                  ))}
                </div>
              )}
            </section>

            {/* 공지사항 */}
            <section className="mt-9">
              <div className="flex items-center justify-between mb-4">
                <div className="flex items-center gap-3">
                  <h2 className="m-0 text-[24px] font-bold leading-normal text-[#1B2027]">공지사항</h2>
                  <div className="text-[15px] font-medium leading-normal text-[#333C47]">
                    총 <span className="text-[#384FBF]">{notices.length}</span>건
                  </div>
                </div>
                <Link
                  href="/notices"
                  className="flex items-center gap-0.5 text-[14px] font-medium leading-normal text-[#6C7682] no-underline"
                >
                  전체보기
                  <svg width="16" height="16" viewBox="0 0 24 24" aria-hidden>
                    <path
                      d="M8 5l8 7-8 7"
                      fill="none"
                      stroke="currentColor"
                      strokeWidth="2"
                      strokeLinecap="round"
                      strokeLinejoin="round"
                    />
                  </svg>
                </Link>
              </div>

              {loadingNotices ? (
                <div className="flex items-center justify-center h-[240px]">
                  <p className="text-[16px] font-medium text-[#6C7682]">로딩 중...</p>
                </div>
              ) : (
                <div className="rounded-[8px] border border-[#DEE1E6] overflow-hidden bg-white">
                  <div className="grid grid-cols-[57px_1fr_140px_140px_140px] bg-[#F9FAFB] h-[48px] text-[14px] font-semibold text-[#4C5561] border-b border-[#DEE1E6]">
                    <div className="flex items-center justify-center px-2 whitespace-nowrap border-r border-[#DEE1E6]">번호</div>
                    <div className="flex items-center px-4 border-r border-[#DEE1E6]">제목</div>
                    <div className="flex items-center px-4 border-r border-[#DEE1E6]">게시일</div>
                    <div className="flex items-center px-4 border-r border-[#DEE1E6]">조회수</div>
                    <div className="flex items-center px-4">작성자</div>
                  </div>

                  <div>
                    {notices.map((notice, index) => {
                      // 번호는 정렬된 목록에서의 순서 (최신이 1번)
                      const noticeNumber = notices.length - index;
                      return (
                        <div
                          key={notice.id}
                          role="button"
                          tabIndex={0}
                          onClick={() => router.push(`/notices/${notice.id}`)}
                          onKeyDown={(e) => {
                            if (e.key === 'Enter' || e.key === ' ') {
                              e.preventDefault();
                              router.push(`/notices/${notice.id}`);
                            }
                          }}
                          className="grid grid-cols-[57px_1fr_140px_140px_140px] h-[48px] text-[15px] font-medium text-[#1B2027] border-t border-[#DEE1E6] hover:bg-[rgba(236,240,255,0.5)] cursor-pointer"
                        >
                          <div className="flex items-center justify-center px-2 whitespace-nowrap border-r border-[#DEE1E6]">{noticeNumber}</div>
                          <div
                            className="flex items-center px-4 border-r border-[#DEE1E6] whitespace-nowrap overflow-hidden text-ellipsis"
                            title={notice.title}
                          >
                            {notice.title}
                          </div>
                          <div className="flex items-center px-4 border-r border-[#DEE1E6]">{notice.date}</div>
                          <div className="flex items-center px-4 border-r border-[#DEE1E6]">{notice.views.toLocaleString()}</div>
                          <div className="flex items-center px-4">{notice.writer}</div>
                        </div>
                      );
                    })}
                  </div>
                </div>
              )}
            </section>
          </div>
        </div>
      </main>

      {/* 전역 Footer는 layout.tsx에서 렌더링됩니다. */}
    </div>
  );
}