'use client';

import { useState, useEffect, useCallback } from 'react';
import { useRouter, useSearchParams } from 'next/navigation';
import { CreditCard, Save, Trash2, X, Edit, Loader2, ExternalLink } from 'lucide-react';
import { Button } from '@/components/ui/button';
import { CardNumberInput } from '@/components/ui/card-number-input';
import { formatCardNumber } from '@/lib/formatters';
import { Badge } from '@/components/ui/badge';
import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
import { DeleteConfirmDialog } from '@/components/ui/confirm-dialog';
import { useDeleteDialog } from '@/hooks/useDeleteDialog';
import { PageLayout } from '@/components/organisms/PageLayout';
import { PageHeader } from '@/components/organisms/PageHeader';
import { ContentSkeleton } from '@/components/ui/skeleton';
import { FormField } from '@/components/molecules/FormField';
import { toast } from 'sonner';
import { formatAmountWon as formatCurrency } from '@/lib/utils/amount';
import type { FieldErrors } from '@/lib/api/execute-server-action';
import type { Card as CardType, CardFormData, CardStatus } from './types';
import { cardFormSchema } from './types';
import {
  CARD_COMPANIES,
  CARD_TYPE_OPTIONS,
  PAYMENT_DAY_OPTIONS,
  CARD_STATUS_LABELS,
  CARD_STATUS_COLORS,
  getCardCompanyLabel,
} from './types';
import {
  createCard,
  updateCard,
  deleteCard,
  getActiveEmployees,
} from './actions';

function formatExpiryDate(value: string): string {
  if (value && value.length === 4) {
    return `${value.slice(0, 2)}/${value.slice(2)}`;
  }
  return value || '-';
}

function getPaymentDayLabel(value: string): string {
  const option = PAYMENT_DAY_OPTIONS.find(o => o.value === value);
  return option?.label || value || '-';
}

function getCardTypeLabel(value: string): string {
  const option = CARD_TYPE_OPTIONS.find(o => o.value === value);
  return option?.label || value || '-';
}

// 폼 필드(camelCase) → API 필드(snake_case) 매핑
const FORM_TO_API_FIELD: Record<string, string> = {
  cardCompany: 'card_company',
  cardType: 'card_type',
  cardNumber: 'card_number',
  cardName: 'card_name',
  alias: 'alias',
  expiryDate: 'expiry_date',
  csv: 'csv',
  paymentDay: 'payment_day',
  pinPrefix: 'card_password',
  totalLimit: 'total_limit',
  usedAmount: 'used_amount',
  remainingLimit: 'remaining_limit',
  status: 'status',
  userId: 'assigned_user_id',
  memo: 'memo',
};

// card prop → formData 변환 헬퍼
function buildFormData(card?: CardType): CardFormData {
  return {
    cardCompany: card?.cardCompany || '',
    cardType: card?.cardType || '',
    cardNumber: card?.cardNumber || '',
    cardName: card?.cardName || '',
    alias: card?.alias || '',
    expiryDate: card?.expiryDate || '',
    csv: card?.csv || '',
    paymentDay: card?.paymentDay || '',
    pinPrefix: '',
    totalLimit: card?.totalLimit || 0,
    usedAmount: card?.usedAmount || 0,
    remainingLimit: card?.remainingLimit || 0,
    status: card?.status || 'active',
    userId: card?.user?.id || '',
    departmentId: card?.user?.departmentId || '',
    positionId: card?.user?.positionId || '',
    memo: card?.memo || '',
  };
}

interface CardDetailProps {
  card?: CardType;
  mode: 'create' | 'view' | 'edit';
  isLoading?: boolean;
}

export function CardDetail({ card, mode: initialMode, isLoading }: CardDetailProps) {
  const router = useRouter();
  const searchParams = useSearchParams();
  const [mode, setMode] = useState(initialMode);
  const [isSaving, setIsSaving] = useState(false);
  const [employees, setEmployees] = useState<Array<{ id: string; label: string }>>([]);
  const [fieldErrors, setFieldErrors] = useState<FieldErrors>({});

  useEffect(() => {
    const urlMode = searchParams.get('mode');
    if (urlMode === 'edit' && card) setMode('edit');
  }, [searchParams, card]);

  // 직원 목록 로드 (수정/등록 모드)
  useEffect(() => {
    if (mode !== 'view') {
      getActiveEmployees().then(result => {
        if (result.success && result.data) setEmployees(result.data);
      });
    }
  }, [mode]);

  const [formData, setFormData] = useState<CardFormData>(() => buildFormData(card));

  // card prop 변경 시 formData 동기화 (API 로딩 완료 후)
  useEffect(() => {
    if (card) {
      setFormData(buildFormData(card));
    }
  }, [card]);

  const isViewMode = mode === 'view';
  const isCreateMode = mode === 'create';

  const handleChange = useCallback((field: keyof CardFormData, value: string | number) => {
    setFormData(prev => ({ ...prev, [field]: value }));
    const apiField = FORM_TO_API_FIELD[field] || field;
    setFieldErrors(prev => {
      if (!prev[apiField]) return prev;
      const next = { ...prev };
      delete next[apiField];
      return next;
    });
  }, []);

  // API 필드명으로 에러 메시지 조회
  const getError = (apiField: string) => fieldErrors[apiField]?.[0];

  const handleBack = () => {
    router.push('/ko/hr/card-management');
  };

  const handleSubmit = async () => {
    const validation = cardFormSchema.safeParse(formData);
    if (!validation.success) {
      const zodErrors: FieldErrors = {};
      for (const issue of validation.error.issues) {
        const field = String(issue.path[0]);
        const apiField = FORM_TO_API_FIELD[field] || field;
        if (!zodErrors[apiField]) zodErrors[apiField] = [];
        zodErrors[apiField].push(issue.message);
      }
      setFieldErrors(zodErrors);
      const firstMsg = validation.error.issues[0]?.message || '입력값을 확인해주세요.';
      toast.error(firstMsg);
      return;
    }

    setFieldErrors({});
    setIsSaving(true);
    try {
      const result = isCreateMode
        ? await createCard(formData)
        : card?.id ? await updateCard(card.id, formData) : null;

      if (!result) return;

      if (result.success) {
        toast.success(isCreateMode ? '카드가 등록되었습니다.' : '카드가 수정되었습니다.');
        router.push('/ko/hr/card-management');
      } else {
        if (result.fieldErrors) {
          setFieldErrors(result.fieldErrors);
        }
        toast.error(result.error || (isCreateMode ? '카드 등록에 실패했습니다.' : '카드 수정에 실패했습니다.'));
      }
    } catch {
      toast.error('저장 중 오류가 발생했습니다.');
    } finally {
      setIsSaving(false);
    }
  };

  const deleteDialog = useDeleteDialog({
    onDelete: async (id) => deleteCard(id),
    onSuccess: () => router.push('/ko/hr/card-management'),
    entityName: '카드',
  });

  const handleCancel = () => {
    setFieldErrors({});
    if (isCreateMode) {
      router.push('/ko/hr/card-management');
    } else {
      setMode('view');
      setFormData(buildFormData(card));
    }
  };

  const handleEdit = () => {
    setMode('edit');
    if (card?.id) {
      router.push(`/ko/hr/card-management/${card.id}?mode=edit`);
    }
  };

  const handleApprovalForm = () => {
    router.push('/ko/approval/draft/new');
  };

  if (isLoading) {
    return (
      <PageLayout>
        <PageHeader title="카드 상세" description="카드 정보를 관리합니다" icon={CreditCard} />
        <ContentSkeleton type="detail" />
      </PageLayout>
    );
  }

  // ===== 뷰 모드 =====
  if (isViewMode) {
    return (
      <PageLayout>
        <PageHeader title="카드 상세" description="카드 정보를 관리합니다" icon={CreditCard} />

        <div className="space-y-6">
          {/* 기본 정보 */}
          <Card>
            <CardHeader>
              <CardTitle className="text-base">기본 정보</CardTitle>
            </CardHeader>
            <CardContent>
              <dl className="grid grid-cols-2 md:grid-cols-4 gap-4">
                <div>
                  <dt className="text-sm font-medium text-muted-foreground">카드사</dt>
                  <dd className="text-sm mt-1">{getCardCompanyLabel(card?.cardCompany || '')}</dd>
                </div>
                <div>
                  <dt className="text-sm font-medium text-muted-foreground">종류</dt>
                  <dd className="text-sm mt-1">{getCardTypeLabel(card?.cardType || '')}</dd>
                </div>
                <div>
                  <dt className="text-sm font-medium text-muted-foreground">카드번호</dt>
                  <dd className="text-sm mt-1 font-mono">{card?.cardNumber ? formatCardNumber(card.cardNumber) : '-'}</dd>
                </div>
                <div>
                  <dt className="text-sm font-medium text-muted-foreground">카드명</dt>
                  <dd className="text-sm mt-1">{card?.cardName || '-'}</dd>
                </div>

                <div>
                  <dt className="text-sm font-medium text-muted-foreground">카드 별칭</dt>
                  <dd className="text-sm mt-1">{card?.alias || '-'}</dd>
                </div>
                <div>
                  <dt className="text-sm font-medium text-muted-foreground">유효기간(15/05)</dt>
                  <dd className="text-sm mt-1">{formatExpiryDate(card?.expiryDate || '')}</dd>
                </div>
                <div>
                  <dt className="text-sm font-medium text-muted-foreground">CSV</dt>
                  <dd className="text-sm mt-1">{card?.csv || '-'}</dd>
                </div>
                <div>
                  <dt className="text-sm font-medium text-muted-foreground">결제일</dt>
                  <dd className="text-sm mt-1">{getPaymentDayLabel(card?.paymentDay || '')}</dd>
                </div>

                <div>
                  <dt className="text-sm font-medium text-muted-foreground">총 한도</dt>
                  <dd className="text-sm mt-1 font-medium">{formatCurrency(card?.totalLimit || 0)}</dd>
                </div>
                <div>
                  <dt className="text-sm font-medium text-muted-foreground">사용 금액</dt>
                  <dd className="text-sm mt-1 font-medium text-red-600">{formatCurrency(card?.usedAmount || 0)}</dd>
                </div>
                <div>
                  <dt className="text-sm font-medium text-muted-foreground">잔여한도</dt>
                  <dd className="text-sm mt-1 font-medium">{formatCurrency(card?.remainingLimit || 0)}</dd>
                </div>
                <div>
                  <dt className="text-sm font-medium text-muted-foreground">상태</dt>
                  <dd className="mt-1">
                    <Badge className={CARD_STATUS_COLORS[card?.status || 'active']}>
                      {CARD_STATUS_LABELS[card?.status || 'active']}
                    </Badge>
                  </dd>
                </div>
              </dl>
            </CardContent>
          </Card>

          {/* 사용자 정보 */}
          <Card>
            <CardHeader>
              <CardTitle className="text-base">사용자 정보</CardTitle>
            </CardHeader>
            <CardContent>
              <dl className="grid grid-cols-2 md:grid-cols-4 gap-4">
                <div>
                  <dt className="text-sm font-medium text-muted-foreground">부서</dt>
                  <dd className="text-sm mt-1">{card?.user?.departmentName || '-'}</dd>
                </div>
                <div>
                  <dt className="text-sm font-medium text-muted-foreground">사용자</dt>
                  <dd className="text-sm mt-1">{card?.user?.employeeName || '-'}</dd>
                </div>
                <div>
                  <dt className="text-sm font-medium text-muted-foreground">직책</dt>
                  <dd className="text-sm mt-1">{card?.user?.positionName || '-'}</dd>
                </div>
                <div>
                  <dt className="text-sm font-medium text-muted-foreground">메모</dt>
                  <dd className="text-sm mt-1">{card?.memo || '-'}</dd>
                </div>
              </dl>
            </CardContent>
          </Card>

          {/* 선결제 신청 */}
          <Card>
            <CardHeader>
              <CardTitle className="text-base">선결제 신청</CardTitle>
            </CardHeader>
            <CardContent>
              <p className="text-sm text-muted-foreground mb-4">
                한도를 초과한 월 경우 품의서를 작성해서 승인을 요청하세요
              </p>
              <Button
                variant="outline"
                onClick={handleApprovalForm}
              >
                <ExternalLink className="h-4 w-4 mr-2" />
                품의서 작성
              </Button>
            </CardContent>
          </Card>

          {/* 하단 버튼 */}
          <div className="flex items-center justify-end gap-2">
            <Button variant="outline" onClick={() => deleteDialog.single.open(card!.id)} className="text-destructive hover:bg-destructive hover:text-destructive-foreground">
              <Trash2 className="w-4 h-4 mr-2" />
              삭제
            </Button>
            <Button onClick={handleEdit}>
              <Edit className="w-4 h-4 mr-2" />
              수정
            </Button>
          </div>
        </div>

        <DeleteConfirmDialog
          open={deleteDialog.single.isOpen}
          onOpenChange={deleteDialog.single.onOpenChange}
          description={
            <>
              카드를 정말 삭제하시겠습니까?
              <br />
              <span className="text-muted-foreground text-sm">
                삭제된 카드 정보는 복구할 수 없습니다.
              </span>
            </>
          }
          onConfirm={deleteDialog.single.confirm}
          loading={deleteDialog.isPending}
        />
      </PageLayout>
    );
  }

  // ===== 생성/수정 모드 =====
  return (
    <PageLayout>
      <PageHeader
        title={isCreateMode ? '수기 카드 등록' : '카드 수정'}
        description="카드 정보를 관리합니다"
        icon={CreditCard}
      />

      <div className="space-y-6">
        {/* 기본 정보 */}
        <Card>
          <CardHeader>
            <CardTitle className="text-base">기본 정보</CardTitle>
          </CardHeader>
          <CardContent className="space-y-4">
            {/* Row 1: 카드사 | 종류 | 카드번호 | 카드명 */}
            <div className="grid grid-cols-2 md:grid-cols-4 gap-4">
              <FormField
                label="카드사"
                required
                type="select"
                value={formData.cardCompany}
                onChange={(v) => handleChange('cardCompany', v)}
                options={[...CARD_COMPANIES]}
                selectPlaceholder="카드사 선택"
                error={getError('card_company')}
              />
              <FormField
                label="종류"
                type="select"
                value={formData.cardType || '_none'}
                onChange={(v) => handleChange('cardType', v === '_none' ? '' : v)}
                options={[{ value: '_none', label: '선택 안함' }, ...CARD_TYPE_OPTIONS]}
                selectPlaceholder="종류 선택"
                error={getError('card_type')}
              />
              <FormField
                label="카드번호"
                type="custom"
                error={getError('card_number')}
              >
                <CardNumberInput
                  value={formData.cardNumber}
                  onChange={(v) => handleChange('cardNumber', v)}
                />
              </FormField>
              <FormField
                label="카드명"
                value={formData.cardName}
                onChange={(v) => handleChange('cardName', v)}
                placeholder="카드명"
                error={getError('card_name')}
              />
            </div>

            {/* Row 2: 카드 별칭 | 유효기간 | CSV | 결제일 */}
            <div className="grid grid-cols-2 md:grid-cols-4 gap-4">
              <FormField
                label="카드 별칭"
                value={formData.alias}
                onChange={(v) => handleChange('alias', v)}
                placeholder="별칭"
                error={getError('alias')}
              />
              <FormField
                label="유효기간(15/05)"
                value={formData.expiryDate}
                onChange={(v) => handleChange('expiryDate', v)}
                placeholder="MMYY"
                maxLength={4}
                error={getError('expiry_date')}
              />
              <FormField
                label="CSV"
                value={formData.csv}
                onChange={(v) => handleChange('csv', v)}
                placeholder="CSV"
                maxLength={4}
                error={getError('csv')}
              />
              <FormField
                label="결제일"
                type="select"
                value={formData.paymentDay || '_none'}
                onChange={(v) => handleChange('paymentDay', v === '_none' ? '' : v)}
                options={[{ value: '_none', label: '선택 안함' }, ...PAYMENT_DAY_OPTIONS]}
                selectPlaceholder="결제일 선택"
                error={getError('payment_day')}
              />
            </div>

            {/* Row 3: 총 한도 | 사용 금액 | 잔여한도 | 상태 */}
            <div className="grid grid-cols-2 md:grid-cols-4 gap-4">
              <FormField
                label="총 한도"
                type="currency"
                value={formData.totalLimit}
                onChangeNumber={(v) => handleChange('totalLimit', v ?? 0)}
                placeholder="0"
                error={getError('total_limit')}
              />
              <FormField
                label="사용 금액"
                type="currency"
                value={formData.usedAmount}
                onChangeNumber={(v) => handleChange('usedAmount', v ?? 0)}
                placeholder="0"
                error={getError('used_amount')}
              />
              <FormField
                label="잔여한도"
                type="currency"
                value={formData.remainingLimit}
                onChangeNumber={(v) => handleChange('remainingLimit', v ?? 0)}
                placeholder="0"
                error={getError('remaining_limit')}
              />
              <FormField
                label="상태"
                type="select"
                value={formData.status}
                onChange={(v) => handleChange('status', v as CardStatus)}
                options={[
                  { value: 'active', label: CARD_STATUS_LABELS.active },
                  { value: 'suspended', label: CARD_STATUS_LABELS.suspended },
                ]}
                selectPlaceholder="상태 선택"
                error={getError('status')}
              />
            </div>
          </CardContent>
        </Card>

        {/* 사용자 정보 */}
        <Card>
          <CardHeader>
            <CardTitle className="text-base">사용자 정보</CardTitle>
          </CardHeader>
          <CardContent>
            <div className="grid grid-cols-2 md:grid-cols-4 gap-4">
              <FormField
                label="부서 / 사용자 / 직책"
                type="select"
                value={formData.userId || '_none'}
                onChange={(v) => handleChange('userId', v === '_none' ? '' : v)}
                options={[{ value: '_none', label: '미지정' }, ...employees.map(e => ({ value: e.id, label: e.label }))]}
                selectPlaceholder="사용자 선택"
                error={getError('assigned_user_id')}
                className="md:col-span-2"
              />
              <FormField
                label="메모"
                type="textarea"
                value={formData.memo}
                onChange={(v) => handleChange('memo', v)}
                placeholder="메모"
                rows={2}
                error={getError('memo')}
                className="md:col-span-2"
              />
            </div>
          </CardContent>
        </Card>

        {/* 하단 버튼 */}
        <div className="flex items-center justify-between">
          <Button variant="outline" onClick={handleCancel}>
            <X className="w-4 h-4 mr-2" />
            취소
          </Button>
          <Button onClick={handleSubmit} disabled={isSaving}>
            {isSaving ? (
              <Loader2 className="h-4 w-4 mr-2 animate-spin" />
            ) : (
              <Save className="w-4 h-4 mr-2" />
            )}
            {isCreateMode ? '등록' : '저장'}
          </Button>
        </div>
      </div>
    </PageLayout>
  );
}