'use client';

import { useState, useEffect, useCallback } from 'react';
import { getItemList, type ItemOption } from './actions';
import {
  Dialog,
  DialogContent,
  DialogHeader,
  DialogTitle,
  DialogFooter,
} from '@/components/ui/dialog';
import { Button } from '@/components/ui/button';
import { Input } from '@/components/ui/input';
import { Label } from '@/components/ui/label';
import { QuantityInput } from '@/components/ui/quantity-input';
import { RadioGroup, RadioGroupItem } from '@/components/ui/radio-group';
import { Switch } from '@/components/ui/switch';
import { Checkbox } from '@/components/ui/checkbox';
import {
  Select,
  SelectContent,
  SelectItem,
  SelectTrigger,
  SelectValue,
} from '@/components/ui/select';
import {
  Table,
  TableBody,
  TableCell,
  TableHead,
  TableHeader,
  TableRow,
} from '@/components/ui/table';
import { Search, Package } from 'lucide-react';
import type {
  ClassificationRule,
  RuleRegistrationType,
  RuleType,
  MatchingType,
} from '@/types/process';
import { RULE_TYPE_OPTIONS, MATCHING_TYPE_OPTIONS } from '@/types/process';

// 품목 유형 옵션
const ITEM_TYPE_OPTIONS = [
  { value: 'all', label: '전체' },
  { value: '제품', label: '제품' },
  { value: '반제품', label: '반제품' },
  { value: '원자재', label: '원자재' },
  { value: '부자재', label: '부자재' },
];

interface RuleModalProps {
  open: boolean;
  onOpenChange: (open: boolean) => void;
  onAdd: (rule: Omit<ClassificationRule, 'id' | 'createdAt'>) => void;
  editRule?: ClassificationRule;
}

export function RuleModal({ open, onOpenChange, onAdd, editRule }: RuleModalProps) {
  // 공통 상태
  const [registrationType, setRegistrationType] = useState<RuleRegistrationType>(
    editRule?.registrationType || 'pattern'
  );
  const [description, setDescription] = useState(editRule?.description || '');

  // 패턴 규칙용 상태
  const [ruleType, setRuleType] = useState<RuleType>(editRule?.ruleType || '품목코드');
  const [matchingType, setMatchingType] = useState<MatchingType>(
    editRule?.matchingType || 'startsWith'
  );
  const [conditionValue, setConditionValue] = useState(editRule?.conditionValue || '');
  const [priority, setPriority] = useState(editRule?.priority || 10);
  const [isActive, setIsActive] = useState(editRule?.isActive ?? true);

  // 개별 품목용 상태
  const [searchKeyword, setSearchKeyword] = useState('');
  const [selectedItemType, setSelectedItemType] = useState('all');
  const [selectedItemIds, setSelectedItemIds] = useState<Set<string>>(new Set());

  // 품목 목록 API 상태
  const [itemList, setItemList] = useState<ItemOption[]>([]);
  const [isItemsLoading, setIsItemsLoading] = useState(false);

  // 품목 목록 로드 (debounced)
  const loadItems = useCallback(async (q?: string, itemType?: string) => {
    setIsItemsLoading(true);
    const items = await getItemList({
      q: q || undefined,
      itemType: itemType === 'all' ? undefined : itemType,
      size: 1000, // 전체 품목 조회
    });
    setItemList(items);
    setIsItemsLoading(false);
  }, []);

  // 검색어 유효성 검사 함수
  const isValidSearchKeyword = (keyword: string): boolean => {
    if (!keyword || keyword.trim() === '') return false;

    const trimmed = keyword.trim();
    // 한글이 포함되어 있으면 1자 이상
    const hasKorean = /[가-힣]/.test(trimmed);
    if (hasKorean) return trimmed.length >= 1;

    // 영어/숫자만 있으면 2자 이상
    return trimmed.length >= 2;
  };

  // 검색어/품목유형 변경 시 API 호출 (debounce)
  useEffect(() => {
    if (registrationType !== 'individual') return;

    // 검색어 유효성 검사 - 유효하지 않으면 빈 목록
    if (!isValidSearchKeyword(searchKeyword)) {
      setItemList([]);
      return;
    }

    const timer = setTimeout(() => {
      loadItems(searchKeyword, selectedItemType);
    }, 300);

    return () => clearTimeout(timer);
  }, [searchKeyword, selectedItemType, registrationType, loadItems]);

  // 품목유형 변경 시 검색어가 유효하면 재검색
  useEffect(() => {
    if (registrationType !== 'individual') return;
    if (!isValidSearchKeyword(searchKeyword)) return;

    loadItems(searchKeyword, selectedItemType);
  }, [selectedItemType]);

  // 모달 열릴 때 품목 목록 초기화 (초기 로드 안함)
  useEffect(() => {
    if (open && registrationType === 'individual') {
      setItemList([]);
      setSearchKeyword('');
    }
  }, [open, registrationType]);

  // 체크박스 토글
  const handleToggleItem = (id: string) => {
    setSelectedItemIds((prev) => {
      const newSet = new Set(prev);
      if (newSet.has(id)) {
        newSet.delete(id);
      } else {
        newSet.add(id);
      }
      return newSet;
    });
  };

  // 전체 선택
  const handleSelectAll = () => {
    const allIds = itemList.map((item) => item.id);
    setSelectedItemIds(new Set(allIds));
  };

  // 초기화
  const handleResetSelection = () => {
    setSelectedItemIds(new Set());
  };

  // 모달 열릴 때 초기화 또는 수정 데이터 로드
  useEffect(() => {
    if (open) {
      if (editRule) {
        // 수정 모드: 기존 데이터 로드
        setRegistrationType(editRule.registrationType);
        setDescription(editRule.description || '');
        setRuleType(editRule.ruleType);
        setMatchingType(editRule.matchingType);
        setConditionValue(editRule.conditionValue);
        setPriority(editRule.priority);
        setIsActive(editRule.isActive);
        setSearchKeyword('');
        setSelectedItemType('all');

        // 개별 품목인 경우 선택된 품목 ID 설정
        if (editRule.registrationType === 'individual') {
          const ids = editRule.conditionValue.split(',').filter(Boolean);
          setSelectedItemIds(new Set(ids));
        } else {
          setSelectedItemIds(new Set());
        }
      } else {
        // 추가 모드: 초기화
        setRegistrationType('pattern');
        setDescription('');
        setRuleType('품목코드');
        setMatchingType('startsWith');
        setConditionValue('');
        setPriority(10);
        setIsActive(true);
        setSearchKeyword('');
        setSelectedItemType('all');
        setSelectedItemIds(new Set());
      }
    }
  }, [open, editRule]);

  const handleSubmit = () => {
    if (registrationType === 'pattern') {
      if (!conditionValue.trim()) {
        alert('조건 값을 입력해주세요.');
        return;
      }
    } else {
      if (selectedItemIds.size === 0) {
        alert('품목을 최소 1개 이상 선택해주세요.');
        return;
      }
    }

    // 개별 품목의 경우 conditionValue에 품목코드들을 저장
    const finalConditionValue =
      registrationType === 'individual'
        ? Array.from(selectedItemIds).join(',')
        : conditionValue.trim();

    onAdd({
      registrationType,
      ruleType: registrationType === 'individual' ? '품목코드' : ruleType,
      matchingType: registrationType === 'individual' ? 'equals' : matchingType,
      conditionValue: finalConditionValue,
      priority: registrationType === 'individual' ? 10 : priority,
      description: description.trim() || undefined,
      isActive: registrationType === 'individual' ? true : isActive,
    });

    // Reset form
    setRegistrationType('pattern');
    setDescription('');
    setRuleType('품목코드');
    setMatchingType('startsWith');
    setConditionValue('');
    setPriority(10);
    setIsActive(true);
    setSearchKeyword('');
    setSelectedItemType('all');
    setSelectedItemIds(new Set());

    onOpenChange(false);
  };

  return (
    <Dialog open={open} onOpenChange={onOpenChange}>
      <DialogContent className={registrationType === 'individual' ? 'max-w-xl max-h-[90vh] flex flex-col' : 'max-w-md'}>
        <DialogHeader>
          <DialogTitle>{editRule ? '규칙 수정' : '규칙 추가'}</DialogTitle>
        </DialogHeader>

        <div className="space-y-4 py-4 overflow-y-auto flex-1">
          {/* 등록 방식 */}
          <div className="space-y-3">
            <Label>등록 방식 *</Label>
            <RadioGroup
              value={registrationType}
              onValueChange={(v) => setRegistrationType(v as RuleRegistrationType)}
            >
              <div className="flex items-center space-x-2">
                <RadioGroupItem value="pattern" id="pattern" />
                <Label htmlFor="pattern" className="font-normal">
                  패턴 규칙 (코드/명칭 기반 자동 분류)
                </Label>
              </div>
              <div className="flex items-center space-x-2">
                <RadioGroupItem value="individual" id="individual" />
                <Label htmlFor="individual" className="font-normal">
                  개별 품목 (특정 품목 직접 지정)
                </Label>
              </div>
            </RadioGroup>
          </div>

          {/* 패턴 규칙 UI */}
          {registrationType === 'pattern' && (
            <>
              {/* 규칙 유형 */}
              <div className="space-y-2">
                <Label>규칙 유형 *</Label>
                <Select value={ruleType} onValueChange={(v) => setRuleType(v as RuleType)}>
                  <SelectTrigger>
                    <SelectValue />
                  </SelectTrigger>
                  <SelectContent>
                    {RULE_TYPE_OPTIONS.map((opt) => (
                      <SelectItem key={opt.value} value={opt.value}>
                        {opt.label}
                      </SelectItem>
                    ))}
                  </SelectContent>
                </Select>
              </div>

              {/* 매칭 방식 */}
              <div className="space-y-2">
                <Label>매칭 방식 *</Label>
                <Select
                  value={matchingType}
                  onValueChange={(v) => setMatchingType(v as MatchingType)}
                >
                  <SelectTrigger>
                    <SelectValue />
                  </SelectTrigger>
                  <SelectContent>
                    {MATCHING_TYPE_OPTIONS.map((opt) => (
                      <SelectItem key={opt.value} value={opt.value}>
                        {opt.label}
                      </SelectItem>
                    ))}
                  </SelectContent>
                </Select>
              </div>

              {/* 조건 값 */}
              <div className="space-y-2">
                <Label>조건 값 *</Label>
                <div className="flex gap-2">
                  <Input
                    value={conditionValue}
                    onChange={(e) => setConditionValue(e.target.value)}
                    placeholder="예: SCR-, E-, STEEL-"
                    className="flex-1"
                  />
                  <Button variant="outline" size="icon">
                    <Search className="h-4 w-4" />
                  </Button>
                </div>
                <p className="text-xs text-muted-foreground">
                  Enter 키를 누르거나 검색 버튼을 클릭하세요
                </p>
              </div>

              {/* 우선순위 - 패턴 규칙에서만 표시 */}
              <div className="space-y-2">
                <Label>우선순위</Label>
                <QuantityInput
                  value={priority}
                  onChange={(value) => setPriority(value ?? 1)}
                  min={1}
                  max={100}
                  className="w-24"
                />
                <p className="text-xs text-muted-foreground">낮을수록 먼저 적용됩니다</p>
              </div>

              {/* 설명 - 패턴 규칙 */}
              <div className="space-y-2">
                <Label>설명</Label>
                <Input
                  value={description}
                  onChange={(e) => setDescription(e.target.value)}
                  placeholder="규칙에 대한 설명"
                />
              </div>

              {/* 활성 상태 - 패턴 규칙에서만 표시 */}
              <div className="flex items-center justify-between">
                <Label>활성 상태</Label>
                <Switch checked={isActive} onCheckedChange={setIsActive} />
              </div>
            </>
          )}

          {/* 개별 품목 UI - 기획서 기준 */}
          {registrationType === 'individual' && (
            <>
              {/* 설명 (선택) */}
              <div className="space-y-2">
                <Label>설명 (선택)</Label>
                <Input
                  value={description}
                  onChange={(e) => setDescription(e.target.value)}
                  placeholder="이 품목 그룹에 대한 설명"
                />
              </div>

              {/* 품목 검색 + 품목 유형 필터 */}
              <div className="flex gap-3">
                <div className="flex-1">
                  <Label className="text-sm">품목 검색</Label>
                  <div className="relative mt-1">
                    <Search className="absolute left-3 top-1/2 -translate-y-1/2 h-4 w-4 text-muted-foreground" />
                    <Input
                      value={searchKeyword}
                      onChange={(e) => setSearchKeyword(e.target.value)}
                      placeholder="품목코드 또는 품목명으로 검색..."
                      className="pl-9"
                    />
                  </div>
                </div>
                <div className="w-32">
                  <Label className="text-sm">품목 유형</Label>
                  <Select value={selectedItemType} onValueChange={setSelectedItemType}>
                    <SelectTrigger className="mt-1">
                      <SelectValue />
                    </SelectTrigger>
                    <SelectContent>
                      {ITEM_TYPE_OPTIONS.map((opt) => (
                        <SelectItem key={opt.value} value={opt.value}>
                          {opt.label}
                        </SelectItem>
                      ))}
                    </SelectContent>
                  </Select>
                </div>
              </div>

              {/* 품목 목록 헤더 */}
              <div className="flex items-center justify-between">
                <div className="flex items-center gap-2 text-sm">
                  <Package className="h-4 w-4" />
                  <span>
                    {isItemsLoading ? (
                      '로딩 중...'
                    ) : (
                      <>품목 목록 ({itemList.length}개) | 선택됨 ({selectedItemIds.size}개)</>
                    )}
                  </span>
                </div>
                <div className="flex gap-2">
                  <Button
                    type="button"
                    variant="ghost"
                    size="sm"
                    onClick={handleSelectAll}
                    className="text-xs h-7"
                    disabled={isItemsLoading || itemList.length === 0}
                  >
                    전체 선택
                  </Button>
                  <span className="text-muted-foreground">|</span>
                  <Button
                    type="button"
                    variant="ghost"
                    size="sm"
                    onClick={handleResetSelection}
                    className="text-xs h-7"
                    disabled={selectedItemIds.size === 0}
                  >
                    초기화
                  </Button>
                </div>
              </div>

              {/* 품목 테이블 */}
              <div className="border rounded-lg max-h-[280px] overflow-auto">
                <Table>
                  <TableHeader>
                    <TableRow className="bg-muted/50">
                      <TableHead className="w-[40px]"></TableHead>
                      <TableHead>품목코드</TableHead>
                      <TableHead>품목명</TableHead>
                      <TableHead className="w-[80px]">품목유형</TableHead>
                    </TableRow>
                  </TableHeader>
                  <TableBody>
                    {isItemsLoading ? (
                      <TableRow key="loading">
                        <TableCell colSpan={4} className="text-center text-muted-foreground py-8">
                          품목 목록을 불러오는 중...
                        </TableCell>
                      </TableRow>
                    ) : itemList.length === 0 ? (
                      <TableRow key="empty">
                        <TableCell colSpan={4} className="text-center text-muted-foreground py-8">
                          {searchKeyword.trim() === ''
                            ? '품목을 검색해주세요 (한글 1자 이상, 영문 2자 이상)'
                            : '검색 결과가 없습니다'}
                        </TableCell>
                      </TableRow>
                    ) : (
                      itemList.map((item) => (
                        <TableRow
                          key={item.id}
                          className="cursor-pointer hover:bg-muted/50"
                          onClick={() => handleToggleItem(item.id)}
                        >
                          <TableCell>
                            <Checkbox
                              checked={selectedItemIds.has(item.id)}
                              onCheckedChange={() => handleToggleItem(item.id)}
                              onClick={(e) => e.stopPropagation()}
                            />
                          </TableCell>
                          <TableCell className="font-medium">{item.code}</TableCell>
                          <TableCell>{item.fullName}</TableCell>
                          <TableCell>{item.type}</TableCell>
                        </TableRow>
                      ))
                    )}
                  </TableBody>
                </Table>
              </div>

              {/* 안내 문구 */}
              <p className="text-xs text-muted-foreground">
                이 공정에 배정할 품목을 선택하세요. 다른 공정에 이미 배정된 품목은 표시되지 않습니다.
              </p>
            </>
          )}
        </div>

        <DialogFooter>
          <Button variant="outline" onClick={() => onOpenChange(false)}>
            취소
          </Button>
          <Button onClick={handleSubmit}>{editRule ? '수정' : '추가'}</Button>
        </DialogFooter>
      </DialogContent>
    </Dialog>
  );
}