'use client';

import { useState, useEffect } from 'react';
import { useRouter, useParams } from 'next/navigation';
import BackCircleSvg from '../../svgs/backcirclesvg';
import DownloadIcon from '../../svgs/downloadicon';
import apiService from '../../lib/apiService';
import type { Notice } from '../../admin/notices/mockData';

type Attachment = {
  name: string;
  size: string;
  url?: string;
  fileKey?: string;
};

export default function NoticeDetailPage() {
  const params = useParams();
  const router = useRouter();
  const [notice, setNotice] = useState<Notice | null>(null);
  const [attachments, setAttachments] = useState<Attachment[]>([]);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState<string | null>(null);

  // 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;
    }
  };

  useEffect(() => {
    async function fetchNotice() {
      if (!params?.id) return;

      try {
        setLoading(true);
        setError(null);
        
        const noticeId = Array.isArray(params.id) ? params.id[0] : params.id;
        const response = await apiService.getNotice(noticeId);
        const data = response.data;

        // API 응답 데이터를 Notice 형식으로 변환
        const transformedNotice: Notice = {
          id: data.id || data.noticeId || Number(params.id),
          title: data.title || '',
          date: formatDate(data.date || data.createdAt || data.createdDate || new Date().toISOString().split('T')[0]),
          views: data.views || data.viewCount || 0,
          writer: data.writer || data.author || data.createdBy || '관리자',
          content: data.content 
            ? (Array.isArray(data.content) 
                ? data.content 
                : typeof data.content === 'string' 
                  ? data.content.split('\n').filter((line: string) => line.trim())
                  : [String(data.content)])
            : [],
          hasAttachment: data.hasAttachment || data.attachment || false,
        };

        // 첨부파일 정보 처리
        if (data.attachments && Array.isArray(data.attachments)) {
          setAttachments(data.attachments.map((att: any) => ({
            name: att.name || att.fileName || att.filename || '',
            size: att.size || att.fileSize || '',
            url: att.url || att.downloadUrl,
            fileKey: att.fileKey || att.key || att.fileId,
          })));
        } else if (transformedNotice.hasAttachment && data.attachment) {
          // 단일 첨부파일인 경우
          setAttachments([{
            name: data.attachment.name || data.attachment.fileName || data.attachment.filename || '첨부파일',
            size: data.attachment.size || data.attachment.fileSize || '',
            url: data.attachment.url || data.attachment.downloadUrl,
            fileKey: data.attachment.fileKey || data.attachment.key || data.attachment.fileId,
          }]);
        }

        if (!transformedNotice.title) {
          setError('공지사항을 찾을 수 없습니다.');
          return;
        }

        setNotice(transformedNotice);
      } catch (err) {
        console.error('공지사항 조회 오류:', err);
        setError('공지사항을 불러오는 중 오류가 발생했습니다.');
      } finally {
        setLoading(false);
      }
    }

    fetchNotice();
  }, [params?.id]);

  const handleDownload = async (fileKey?: string, url?: string, fileName?: string) => {
    if (url) {
      // URL이 있으면 직접 다운로드
      const link = document.createElement('a');
      link.href = url;
      link.download = fileName || 'download';
      document.body.appendChild(link);
      link.click();
      document.body.removeChild(link);
    } else if (fileKey) {
      // fileKey가 있으면 API를 통해 다운로드
      try {
        const fileUrl = await apiService.getFile(fileKey);
        if (fileUrl) {
          const link = document.createElement('a');
          link.href = fileUrl;
          link.download = fileName || 'download';
          document.body.appendChild(link);
          link.click();
          document.body.removeChild(link);
        }
      } catch (error) {
        console.error('파일 다운로드 오류:', error);
        alert('파일 다운로드 중 오류가 발생했습니다.');
      }
    }
  };

  if (loading) {
    return (
      <div className="w-full bg-white">
        <div className="flex justify-center">
          <div className="w-full max-w-[1440px]">
            <div className="h-[100px] flex items-center justify-center">
              <p className="text-[16px] font-medium text-[#6C7682]">로딩 중...</p>
            </div>
          </div>
        </div>
      </div>
    );
  }

  if (error || !notice) {
    return (
      <div className="w-full bg-white">
        <div className="flex justify-center">
          <div className="w-full max-w-[1440px]">
            <div className="h-[100px] flex items-center justify-center">
              <p className="text-[16px] font-medium text-[#6C7682]">{error || '공지사항을 찾을 수 없습니다.'}</p>
            </div>
          </div>
        </div>
      </div>
    );
  }

  return (
    <div className="w-full bg-white">
      <div className="flex justify-center">
        <div className="w-full max-w-[1440px]">
          {/* 상단 타이틀 */}
          <div className="h-[100px] flex items-center gap-3 px-8">
            <button
              type="button"
              onClick={() => router.back()}
              aria-label="뒤로 가기"
              className="size-8 rounded-full inline-flex items-center justify-center text-[#8C95A1] hover:bg-black/5 no-underline cursor-pointer"
            >
              <BackCircleSvg width={32} height={32} />
            </button>
            <h1 className="m-0 text-[24px] font-bold leading-normal text-[#1B2027]">
              공지사항 상세
            </h1>
          </div>

          {/* 카드 */}
          <section className="px-8 pb-8">
            <div className="rounded-[8px] border border-[#DEE1E6] overflow-hidden bg-white">
              {/* 헤더 */}
              <div className="p-8">
                <h2 className="m-0 text-[20px] font-bold leading-normal text-[#333C47]">
                  {notice.title}
                </h2>
                <div className="mt-2 flex items-center gap-4 text-[13px] leading-[1.4]">
                  <span className="text-[#8C95A1]">작성자</span>
                  <span className="text-[#333C47]">{notice.writer}</span>
                  <span className="w-px h-4 bg-[#DEE1E6]" />
                  <span className="text-[#8C95A1]">게시일</span>
                  <span className="text-[#333C47]">{notice.date}</span>
                  <span className="w-px h-4 bg-[#DEE1E6]" />
                  <span className="text-[#8C95A1]">조회수</span>
                  <span className="text-[#333C47]">{notice.views.toLocaleString()}</span>
                </div>
              </div>

              {/* 구분선 */}
              <div className="h-px bg-[#DEE1E6] w-full" />

              {/* 본문 */}
              <div className="p-8 flex flex-col gap-10">
                <div className="text-[15px] leading-normal text-[#333C47]">
                  {notice.content && notice.content.length > 0 ? (
                    notice.content.map((p, idx) => (
                      <p key={idx} className="m-0 mb-2 last:mb-0">
                        {p}
                      </p>
                    ))
                  ) : (
                    <p className="m-0">내용이 없습니다.</p>
                  )}
                </div>

                {/* 첨부파일 섹션 */}
                {attachments.length > 0 && (
                  <div className="flex flex-col gap-8">
                    <div className="text-[15px] font-semibold leading-[1.5] text-[#6C7682]">
                      첨부 파일
                    </div>
                    <div className="pt-3">
                      {attachments.map((attachment, idx) => (
                      <div
                        key={idx}
                        className="bg-white border border-[#DEE1E6] rounded-[6px] h-[64px] flex items-center gap-3 px-[17px]"
                      >
                        <div className="size-6 flex items-center justify-center">
                          <svg
                            width="24"
                            height="24"
                            viewBox="0 0 24 24"
                            fill="none"
                            xmlns="http://www.w3.org/2000/svg"
                            className="text-[#8C95A1]"
                          >
                            <path
                              d="M14 2H6C5.46957 2 4.96086 2.21071 4.58579 2.58579C4.21071 2.96086 4 3.46957 4 4V20C4 20.5304 4.21071 21.0391 4.58579 21.4142C4.96086 21.7893 5.46957 22 6 22H18C18.5304 22 19.0391 21.7893 19.4142 21.4142C19.7893 21.0391 20 20.5304 20 20V8L14 2Z"
                              stroke="currentColor"
                              strokeWidth="2"
                              strokeLinecap="round"
                              strokeLinejoin="round"
                            />
                            <path
                              d="M14 2V8H20"
                              stroke="currentColor"
                              strokeWidth="2"
                              strokeLinecap="round"
                              strokeLinejoin="round"
                            />
                          </svg>
                        </div>
                        <div className="flex-1 flex items-center gap-2 min-w-0">
                          <p className="text-[15px] font-normal leading-[1.5] text-[#1B2027] truncate">
                            {attachment.name}
                          </p>
                          <p className="text-[13px] font-normal leading-[1.4] text-[#8C95A1] whitespace-nowrap">
                            {attachment.size}
                          </p>
                        </div>
                        <button
                          type="button"
                          onClick={() => handleDownload(attachment.fileKey, attachment.url, attachment.name)}
                          className="bg-white border border-[#8C95A1] rounded-[6px] h-8 px-4 flex items-center justify-center gap-1 hover:bg-[#F9FAFB] transition-colors"
                        >
                          <DownloadIcon width={16} height={16} className="text-[#4C5561]" />
                          <span className="text-[13px] font-medium leading-[1.4] text-[#4C5561]">
                            다운로드
                          </span>
                        </button>
                      </div>
                      ))}
                    </div>
                  </div>
                )}
              </div>
            </div>
          </section>
        </div>
      </div>
    </div>
  );
}