/**
 * 품목 목록 Client Component - UniversalListPage 마이그레이션
 *
 * 품목기준관리 API 연동
 * - 품목 목록: useItemList 훅으로 API 조회 (서버 사이드 검색/필터링)
 * - UniversalListPage 기반 공통 UI 적용
 */

'use client';

import { useState, useEffect, useRef } from 'react';
import { useRouter } from 'next/navigation';
import type { ItemMaster } from '@/types/item';
import { ITEM_TYPE_LABELS } from '@/types/item';
import { Button } from '@/components/ui/button';
import { Badge } from '@/components/ui/badge';
import { Checkbox } from '@/components/ui/checkbox';
import { TableRow, TableCell } from '@/components/ui/table';
import { DeleteConfirmDialog } from '@/components/ui/confirm-dialog';
import { Search, Plus, Edit, Trash2, Package, FileDown, Upload } from 'lucide-react';
import { downloadExcelTemplate, parseExcelFile, type ExcelColumn, type TemplateColumn } from '@/lib/utils/excel-download';
import { useItemList } from '@/hooks/useItemList';
import { handleApiError } from '@/lib/api/error-handler';
import { isNextRedirectError } from '@/lib/utils/redirect-error';
import {
  UniversalListPage,
  type UniversalListConfig,
  type SelectionHandlers,
  type RowClickHandlers,
  type TabOption,
  type StatCard,
} from '@/components/templates/UniversalListPage';
import { ListMobileCard, InfoField } from '@/components/organisms/MobileCard';

// Debounce 훅
function useDebounce<T>(value: T, delay: number): T {
  const [debouncedValue, setDebouncedValue] = useState<T>(value);

  useEffect(() => {
    const timer = setTimeout(() => setDebouncedValue(value), delay);
    return () => clearTimeout(timer);
  }, [value, delay]);

  return debouncedValue;
}

/**
 * 품목 유형별 Badge 색상 반환
 */
function getItemTypeBadge(itemType: string) {
  const badges: Record<string, { variant: 'default' | 'secondary' | 'outline' | 'destructive'; className: string }> = {
    FG: { variant: 'default', className: 'bg-purple-100 text-purple-700 border-purple-200' },
    PT: { variant: 'default', className: 'bg-orange-100 text-orange-700 border-orange-200' },
    SM: { variant: 'default', className: 'bg-green-100 text-green-700 border-green-200' },
    RM: { variant: 'default', className: 'bg-blue-100 text-blue-700 border-blue-200' },
    CS: { variant: 'default', className: 'bg-gray-100 text-gray-700 border-gray-200' },
  };

  const config = badges[itemType] || { variant: 'outline' as const, className: '' };

  return (
    <Badge variant="outline" className={config.className}>
      {ITEM_TYPE_LABELS[itemType as keyof typeof ITEM_TYPE_LABELS]}
    </Badge>
  );
}

/**
 * 부품 유형 라벨 반환
 */
function getPartTypeLabel(partType: string | undefined): string {
  if (!partType) return '';
  const labels: Record<string, string> = {
    ASSEMBLY: '조립',
    BENDING: '절곡',
    PURCHASED: '구매',
  };
  return labels[partType] || '';
}

export default function ItemListClient() {
  const router = useRouter();
  const [searchTerm, setSearchTerm] = useState('');
  const [selectedType, setSelectedType] = useState<string>('all');

  // 삭제 다이얼로그 상태
  const [deleteDialogOpen, setDeleteDialogOpen] = useState(false);
  const [itemToDelete, setItemToDelete] = useState<{ id: string; code: string; itemType: string } | null>(null);

  // Materials 타입 (SM, RM, CS는 Material 테이블 사용)
  const MATERIAL_TYPES = ['SM', 'RM', 'CS'];

  // API에서 품목 목록 및 테이블 컬럼 조회 (서버 사이드 검색/필터링)
  const {
    items,
    pagination,
    totalStats,
    isLoading,
    isSearching,
    refresh,
    search,
  } = useItemList();

  // 디바운스된 검색어 (300ms 딜레이)
  const debouncedSearchTerm = useDebounce(searchTerm, 300);

  // 검색 상태 추적용 ref
  const isFirstRender = useRef(true);

  // 디바운스된 검색어 변경 시 서버 검색 실행
  useEffect(() => {
    // 첫 렌더링에서는 검색하지 않음
    if (isFirstRender.current) {
      isFirstRender.current = false;
      return;
    }

    search({
      search: debouncedSearchTerm,
      type: selectedType,
      page: 1,
    });
  }, [debouncedSearchTerm, selectedType, search]);

  // 유형 변경 핸들러
  const handleTypeChange = (value: string) => {
    setSelectedType(value);
  };

  // 페이지 변경 핸들러
  const handlePageChange = (page: number) => {
    search({
      search: searchTerm,
      type: selectedType,
      page,
    });
  };

  const handleView = (itemCode: string, itemType: string, itemId: string) => {
    // itemType을 query param으로 전달 (Materials 조회를 위해)
    router.push(`/production/screen-production/${encodeURIComponent(itemCode)}?mode=view&type=${itemType}&id=${itemId}`);
  };

  const handleEdit = (itemCode: string, itemType: string, itemId: string) => {
    // itemType을 query param으로 전달 (Materials 조회를 위해)
    router.push(`/production/screen-production/${encodeURIComponent(itemCode)}?mode=edit&type=${itemType}&id=${itemId}`);
  };

  // 삭제 확인 다이얼로그 열기
  const openDeleteDialog = (itemId: string, itemCode: string, itemType: string) => {
    setItemToDelete({ id: itemId, code: itemCode, itemType });
    setDeleteDialogOpen(true);
  };

  // 삭제 실행
  const handleConfirmDelete = async () => {
    if (!itemToDelete) return;

    try {
      console.log('[Delete] 삭제 요청:', itemToDelete);

      // 2025-12-15: 백엔드 동적 테이블 라우팅 - 모든 품목이 /items 엔드포인트 사용
      // /products/materials 라우트 삭제됨
      const deleteUrl = `/api/proxy/items/${itemToDelete.id}?item_type=${itemToDelete.itemType}`;

      console.log('[Delete] URL:', deleteUrl, '(itemType:', itemToDelete.itemType, ')');

      const response = await fetch(deleteUrl, {
        method: 'DELETE',
        headers: {
          'Content-Type': 'application/json',
        },
      });

      // 🚨 401 인증 에러 시 자동 로그인 페이지 리다이렉트
      if (!response.ok) {
        await handleApiError(response);
      }

      const result = await response.json();
      console.log('[Delete] 응답:', { status: response.status, result });

      if (result.success) {
        refresh();
      } else {
        throw new Error(result.message || '삭제에 실패했습니다.');
      }
    } catch (error) {
      if (isNextRedirectError(error)) throw error;
      console.error('품목 삭제 실패:', error);
      alert(error instanceof Error ? error.message : '품목 삭제에 실패했습니다.');
    } finally {
      setDeleteDialogOpen(false);
      setItemToDelete(null);
    }
  };

  // 일괄 삭제 핸들러
  // 2025-12-15: 백엔드 동적 테이블 라우팅으로 모든 품목에 item_type 필수
  const handleBulkDelete = async (selectedIds: string[]) => {
    let successCount = 0;
    let failCount = 0;

    for (const id of selectedIds) {
      try {
        // 해당 품목의 itemType 찾기
        const item = items.find((i) => i.id === id);
        // 2025-12-15: 백엔드 동적 테이블 라우팅 - 모든 품목이 /items 엔드포인트 사용
        const deleteUrl = `/api/proxy/items/${id}?item_type=${item?.itemType}`;

        const response = await fetch(deleteUrl, {
          method: 'DELETE',
          headers: { 'Content-Type': 'application/json' },
        });

        // 🚨 401 인증 에러 시 자동 로그인 페이지 리다이렉트
        if (response.status === 401) {
          await handleApiError(response);
          return; // 리다이렉트 후 중단
        }

        const result = await response.json();
        if (response.ok && result.success) {
          successCount++;
        } else {
          failCount++;
        }
      } catch {
        failCount++;
      }
    }

    if (successCount > 0) {
      alert(`${successCount}개 품목이 삭제되었습니다.${failCount > 0 ? ` (${failCount}개 실패)` : ''}`);
      refresh();
    } else {
      alert('품목 삭제에 실패했습니다.');
    }
  };

  // 엑셀 다운로드용 컬럼 정의
  const excelColumns: ExcelColumn<ItemMaster>[] = [
    { header: '품목코드', key: 'itemCode', width: 15 },
    { header: '품목유형', key: 'itemType', width: 10, transform: (v) => ITEM_TYPE_LABELS[v as keyof typeof ITEM_TYPE_LABELS] || String(v) },
    { header: '품목명', key: 'itemName', width: 30 },
    { header: '규격', key: 'specification', width: 20 },
    { header: '단위', key: 'unit', width: 8 },
    { header: '대분류', key: 'category1', width: 12 },
    { header: '중분류', key: 'category2', width: 12 },
    { header: '소분류', key: 'category3', width: 12 },
    { header: '구매단가', key: 'purchasePrice', width: 12 },
    { header: '판매단가', key: 'salesPrice', width: 12 },
    { header: '활성상태', key: 'isActive', width: 10, transform: (v) => v ? '활성' : '비활성' },
  ];

  // API 응답을 ItemMaster 타입으로 변환 (엑셀 다운로드용)
  const mapItemResponse = (result: unknown): ItemMaster[] => {
    const data = result as { data?: { data?: Record<string, unknown>[] }; };
    const rawItems = data.data?.data ?? [];
    return rawItems.map((item: Record<string, unknown>) => ({
      id: String(item.id ?? item.item_id ?? ''),
      itemCode: (item.code ?? item.item_code ?? '') as string,
      itemName: (item.name ?? item.item_name ?? '') as string,
      itemType: (item.type_code ?? item.item_type ?? '') as ItemMaster['itemType'],
      partType: item.part_type as ItemMaster['partType'],
      unit: (item.unit ?? '') as string,
      specification: (item.specification ?? '') as string,
      isActive: item.is_active != null ? Boolean(item.is_active) : !item.deleted_at,
      category1: (item.category1 ?? '') as string,
      category2: (item.category2 ?? '') as string,
      category3: (item.category3 ?? '') as string,
      salesPrice: (item.sales_price ?? 0) as number,
      purchasePrice: (item.purchase_price ?? 0) as number,
      currentRevision: (item.current_revision ?? 0) as number,
      isFinal: Boolean(item.is_final ?? false),
      createdAt: (item.created_at ?? '') as string,
      updatedAt: (item.updated_at ?? '') as string,
    }));
  };

  // 업로드용 템플릿 컬럼 정의
  const templateColumns: TemplateColumn[] = [
    { header: '품목코드', key: 'itemCode', required: true, type: 'text', sampleValue: 'KD-FG-001', description: '고유 코드', width: 15 },
    { header: '품목유형', key: 'itemType', required: true, type: 'select', options: ['FG', 'PT', 'SM', 'RM', 'CS'], sampleValue: 'FG', description: 'FG:제품/PT:부품/SM:부자재/RM:원자재/CS:소모품', width: 12 },
    { header: '품목명', key: 'itemName', required: true, type: 'text', sampleValue: '스크린도어 본체', width: 25 },
    { header: '규격', key: 'specification', type: 'text', sampleValue: '1800x2100', width: 15 },
    { header: '단위', key: 'unit', required: true, type: 'select', options: ['EA', 'SET', 'KG', 'M', 'M2', 'BOX'], sampleValue: 'EA', width: 10 },
    { header: '대분류', key: 'category1', type: 'text', sampleValue: '스크린도어', width: 12 },
    { header: '중분류', key: 'category2', type: 'text', sampleValue: '본체류', width: 12 },
    { header: '소분류', key: 'category3', type: 'text', sampleValue: '프레임', width: 12 },
    { header: '구매단가', key: 'purchasePrice', type: 'number', sampleValue: 150000, width: 12 },
    { header: '판매단가', key: 'salesPrice', type: 'number', sampleValue: 200000, width: 12 },
    { header: '활성상태', key: 'isActive', type: 'boolean', sampleValue: 'Y', description: 'Y:활성/N:비활성', width: 10 },
  ];

  // 양식 다운로드
  const handleTemplateDownload = () => {
    downloadExcelTemplate({
      columns: templateColumns,
      filename: '품목등록_양식',
      sheetName: '품목등록',
      includeSampleRow: true,
      includeGuideRow: true,
    });
  };

  // 파일 업로드 input ref
  const fileInputRef = useRef<HTMLInputElement>(null);

  // 양식 업로드 핸들러
  const handleFileUpload = async (e: React.ChangeEvent<HTMLInputElement>) => {
    const file = e.target.files?.[0];
    if (!file) return;

    try {
      const result = await parseExcelFile(file, {
        columns: templateColumns,
        skipRows: 2, // 헤더 + 안내 행 스킵
      });

      if (!result.success || result.errors.length > 0) {
        const errorMessages = result.errors.slice(0, 5).map(
          (err) => `${err.row}행: ${err.message}`
        ).join('\n');
        alert(`업로드 오류:\n${errorMessages}${result.errors.length > 5 ? `\n... 외 ${result.errors.length - 5}건` : ''}`);
        return;
      }

      if (result.data.length === 0) {
        alert('업로드할 데이터가 없습니다.');
        return;
      }

      // TODO: 실제 API 호출로 데이터 저장
      // 지금은 파싱 결과만 확인
      console.log('[Excel Upload] 파싱 결과:', result.data);
      alert(`${result.data.length}건의 데이터가 파싱되었습니다.\n(실제 등록 기능은 추후 구현 예정)`);

    } catch (error) {
      console.error('[Excel Upload] 오류:', error);
      alert('파일 업로드에 실패했습니다.');
    } finally {
      // input 초기화 (같은 파일 재선택 가능하도록)
      if (fileInputRef.current) {
        fileInputRef.current.value = '';
      }
    }
  };

  // 탭 옵션 (품목 유형별)
  const tabs: TabOption[] = [
    { value: 'all', label: '전체', count: totalStats.totalAll, color: 'gray' },
    { value: 'FG', label: '제품', count: totalStats.totalFG, color: 'purple' },
    { value: 'PT', label: '부품', count: totalStats.totalPT, color: 'orange' },
    { value: 'SM', label: '부자재', count: totalStats.totalSM, color: 'green' },
    { value: 'RM', label: '원자재', count: totalStats.totalRM, color: 'blue' },
    { value: 'CS', label: '소모품', count: totalStats.totalCS, color: 'gray' },
  ];

  // 통계 카드 (전체 통계)
  const stats: StatCard[] = [
    { label: '전체 품목', value: totalStats.totalAll, icon: Package, iconColor: 'text-blue-600' },
    { label: '제품', value: totalStats.totalFG, icon: Package, iconColor: 'text-purple-600' },
    { label: '부품', value: totalStats.totalPT, icon: Package, iconColor: 'text-orange-600' },
    { label: '부자재', value: totalStats.totalSM, icon: Package, iconColor: 'text-green-600' },
    { label: '원자재', value: totalStats.totalRM, icon: Package, iconColor: 'text-cyan-600' },
    { label: '소모품', value: totalStats.totalCS, icon: Package, iconColor: 'text-gray-600' },
  ];

  // UniversalListPage Config
  const config: UniversalListConfig<ItemMaster> = {
    // 페이지 기본 정보
    title: '품목 관리',
    description: '제품, 부품, 부자재, 원자재, 소모품 등록 및 관리',
    icon: Package,
    basePath: '/items',

    // ID 추출
    idField: 'id',

    // 테이블 컬럼 (sortable: true로 정렬 가능)
    columns: [
      { key: 'rowNumber', label: '번호', className: 'w-[60px] text-center' },
      { key: 'itemCode', label: '품목코드', className: 'min-w-[120px]' },
      { key: 'itemType', label: '품목유형', className: 'min-w-[100px]' },
      { key: 'itemName', label: '품목명', className: 'min-w-[150px]' },
      { key: 'specification', label: '규격', className: 'min-w-[100px]' },
      { key: 'unit', label: '단위', className: 'min-w-[60px]' },
      { key: 'isActive', label: '품목상태', className: 'min-w-[80px]' },
      { key: 'actions', label: '작업', className: 'w-[120px] text-right' },
    ],

    // 클라이언트 사이드 필터링 (외부 useItemList 훅 사용)
    clientSideFiltering: true,
    itemsPerPage: pagination.perPage,

    // 검색
    searchPlaceholder: '품목코드, 품목명, 규격 검색...',

    // 탭 설정
    tabs,
    defaultTab: 'all',

    // 통계 카드
    stats,

    // 등록 버튼 (createButton 사용 - headerActions 대신)
    createButton: {
      label: '품목 등록',
      onClick: () => router.push('/production/screen-production?mode=new'),
      icon: Plus,
    },

    // 엑셀 다운로드 설정 (공통 기능)
    excelDownload: {
      columns: excelColumns,
      filename: '품목목록',
      sheetName: '품목',
      fetchAllUrl: '/api/proxy/items',
      fetchAllParams: ({ activeTab }): Record<string, string> => {
        // 현재 선택된 타입 필터 적용
        if (activeTab && activeTab !== 'all') {
          return { type: activeTab };
        }
        return { group_id: '1' }; // 품목관리 그룹
      },
      mapResponse: mapItemResponse,
    },

    // 헤더 액션 (양식 다운로드/업로드 - 추후 활성화)
    // headerActions: () => (
    //   <div className="flex items-center gap-2">
    //     <Button variant="outline" size="sm" onClick={handleTemplateDownload} className="gap-2">
    //       <FileDown className="h-4 w-4" />
    //       양식 다운로드
    //     </Button>
    //   </div>
    // ),

    // API 액션 (일괄 삭제 포함)
    actions: {
      getList: async () => ({ success: true, data: items }),
      deleteBulk: async (ids: string[]) => {
        await handleBulkDelete(ids);
        return { success: true };
      },
    },

    // 테이블 행 렌더링
    renderTableRow: (
      item: ItemMaster,
      index: number,
      globalIndex: number,
      handlers: SelectionHandlers & RowClickHandlers<ItemMaster>
    ) => {
      return (
        <TableRow key={item.id} className="hover:bg-muted/50">
          <TableCell className="text-center">
            <Checkbox
              checked={handlers.isSelected}
              onCheckedChange={handlers.onToggle}
            />
          </TableCell>
          <TableCell className="text-muted-foreground text-center">
            {globalIndex}
          </TableCell>
          <TableCell>
            <code className="text-xs bg-gray-100 px-2 py-1 rounded">
              {item.itemCode || '-'}
            </code>
          </TableCell>
          <TableCell>
            <div className="flex items-center gap-1 flex-wrap">
              {getItemTypeBadge(item.itemType)}
              {item.itemType === 'PT' && item.partType && (
                <Badge variant="outline" className="bg-purple-50 text-purple-700 text-xs">
                  {getPartTypeLabel(item.partType)}
                </Badge>
              )}
            </div>
          </TableCell>
          <TableCell>
            <span className="truncate max-w-[200px] block">
              {item.itemName}
            </span>
          </TableCell>
          <TableCell className="text-muted-foreground">
            {item.specification || '-'}
          </TableCell>
          <TableCell>
            <Badge variant="secondary">{item.unit || '-'}</Badge>
          </TableCell>
          <TableCell>
            <Badge variant={item.isActive ? 'default' : 'secondary'}>
              {item.isActive ? '활성' : '비활성'}
            </Badge>
          </TableCell>
          <TableCell className="text-right">
            <div className="flex items-center justify-end gap-1">
              <Button
                variant="ghost"
                size="sm"
                onClick={(e) => { e.stopPropagation(); handleView(item.itemCode, item.itemType, item.id); }}
                title="상세 보기"
              >
                <Search className="w-4 h-4" />
              </Button>
              <Button
                variant="ghost"
                size="sm"
                onClick={(e) => { e.stopPropagation(); handleEdit(item.itemCode, item.itemType, item.id); }}
                title="수정"
              >
                <Edit className="w-4 h-4" />
              </Button>
              <Button
                variant="ghost"
                size="sm"
                onClick={(e) => { e.stopPropagation(); openDeleteDialog(item.id, item.itemCode, item.itemType); }}
                title="삭제"
              >
                <Trash2 className="w-4 h-4 text-red-500" />
              </Button>
            </div>
          </TableCell>
        </TableRow>
      );
    },

    // 모바일 카드 렌더링
    renderMobileCard: (
      item: ItemMaster,
      index: number,
      globalIndex: number,
      handlers: SelectionHandlers & RowClickHandlers<ItemMaster>
    ) => {
      return (
        <ListMobileCard
          key={item.id}
          id={item.id}
          title={item.itemName}
          headerBadges={
            <div className="flex items-center gap-2 flex-wrap">
              <code className="text-xs bg-gray-100 px-2 py-1 rounded">
                {item.itemCode}
              </code>
              {getItemTypeBadge(item.itemType)}
              {item.itemType === 'PT' && item.partType && (
                <Badge variant="outline" className="bg-purple-50 text-purple-700 text-xs">
                  {getPartTypeLabel(item.partType)}
                </Badge>
              )}
            </div>
          }
          statusBadge={
            <Badge variant={item.isActive ? 'default' : 'secondary'}>
              {item.isActive ? '활성' : '비활성'}
            </Badge>
          }
          isSelected={handlers.isSelected}
          onToggleSelection={handlers.onToggle}
          onClick={() => handleView(item.itemCode, item.itemType, item.id)}
          infoGrid={
            <div className="grid grid-cols-2 gap-x-4 gap-y-3">
              {item.specification && (
                <InfoField label="규격" value={item.specification} />
              )}
              {item.unit && (
                <InfoField label="단위" value={item.unit} />
              )}
            </div>
          }
          actions={
            handlers.isSelected ? (
              <div className="flex gap-2 flex-wrap">
                <Button
                  variant="default"
                  size="default"
                  className="flex-1 min-w-[100px] h-11"
                  onClick={(e) => { e.stopPropagation(); handleView(item.itemCode, item.itemType, item.id); }}
                >
                  <Search className="h-4 w-4 mr-2" />
                  상세
                </Button>
                <Button
                  variant="default"
                  size="default"
                  className="flex-1 min-w-[100px] h-11"
                  onClick={(e) => { e.stopPropagation(); handleEdit(item.itemCode, item.itemType, item.id); }}
                >
                  <Edit className="h-4 w-4 mr-2" />
                  수정
                </Button>
                <Button
                  variant="outline"
                  size="default"
                  className="flex-1 min-w-[100px] h-11 border-red-200 text-red-600 hover:border-red-300 bg-[rgba(255,255,255,0)]"
                  onClick={(e) => { e.stopPropagation(); openDeleteDialog(item.id, item.itemCode, item.itemType); }}
                >
                  <Trash2 className="h-4 w-4 mr-2" />
                  삭제
                </Button>
              </div>
            ) : undefined
          }
        />
      );
    },
  };

  return (
    <>
      <UniversalListPage
        config={config}
        initialData={items}
        onTabChange={handleTypeChange}
        externalPagination={{
          currentPage: pagination.currentPage,
          totalPages: pagination.totalPages,
          totalItems: pagination.totalItems,
          itemsPerPage: pagination.perPage,
          onPageChange: handlePageChange,
        }}
        externalIsLoading={isLoading}
      />

      {/* 숨겨진 파일 업로드 input */}
      <input
        ref={fileInputRef}
        type="file"
        accept=".xlsx,.xls"
        onChange={handleFileUpload}
        className="hidden"
      />

      {/* 개별 삭제 확인 다이얼로그 */}
      <DeleteConfirmDialog
        open={deleteDialogOpen}
        onOpenChange={setDeleteDialogOpen}
        onConfirm={handleConfirmDelete}
        title="품목 삭제"
        description={
          <>
            품목 &quot;{itemToDelete?.code}&quot;을(를) 삭제하시겠습니까?
            <br />
            이 작업은 되돌릴 수 없습니다.
          </>
        }
      />
    </>
  );
}