'use client';

import { useState, useCallback } from 'react';
import { useRouter } from 'next/navigation';
import { format, subDays, subMonths } from 'date-fns';
import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
import { Button } from '@/components/ui/button';
import { Input } from '@/components/ui/input';
import {
  Select,
  SelectContent,
  SelectItem,
  SelectTrigger,
  SelectValue,
} from '@/components/ui/select';
import {
  Table,
  TableBody,
  TableCell,
  TableHead,
  TableHeader,
  TableRow,
} from '@/components/ui/table';
import { DateRangeSelector } from '@/components/molecules/DateRangeSelector';
import {
  PageLayout,
  PageHeader,
  StatCards,
  EmptyState,
  SearchableSelectionModal,
} from '@/components/organisms';
import { Checkbox } from '@/components/ui/checkbox';
import { FileText, DollarSign, Calculator, Hash, Settings, PlusCircle, Search } from 'lucide-react';
import { toast } from 'sonner';

import { SupplierSettingModal } from './SupplierSettingModal';
import { TaxInvoiceForm } from './TaxInvoiceForm';
import { createTaxInvoice, searchVendorsForTaxInvoice } from './actions';
import {
  DATE_TYPE_OPTIONS,
  STATUS_OPTIONS,
  SORT_BY_OPTIONS,
  SORT_ORDER_OPTIONS,
  TAX_INVOICE_STATUS_MAP,
  createEmptyBusinessEntity,
} from './types';
import type {
  TaxInvoiceRecord,
  SupplierSettings,
  VendorSearchItem,
  FilterState,
  TaxInvoiceFormData,
  BusinessEntity,
} from './types';

interface TaxInvoiceIssuancePageProps {
  initialData: TaxInvoiceRecord[];
  initialSupplierSettings: SupplierSettings;
}

export function TaxInvoiceIssuancePage({
  initialData,
  initialSupplierSettings,
}: TaxInvoiceIssuancePageProps) {
  const router = useRouter();

  // 데이터
  const [records, setRecords] = useState<TaxInvoiceRecord[]>(initialData);
  const [supplierSettings, setSupplierSettings] = useState<SupplierSettings>(initialSupplierSettings);

  // UI 상태
  const [showNewForm, setShowNewForm] = useState(false);
  const [showSupplierModal, setShowSupplierModal] = useState(false);
  const [showVendorSearch, setShowVendorSearch] = useState(false);
  const [selectedVendor, setSelectedVendor] = useState<BusinessEntity | null>(null);
  const [selectedIds, setSelectedIds] = useState<Set<string>>(new Set());

  // 필터
  const [filters, setFilters] = useState<FilterState>({
    dateType: 'write',
    startDate: format(subMonths(new Date(), 1), 'yyyy-MM-dd'),
    endDate: format(new Date(), 'yyyy-MM-dd'),
    vendorSearch: '',
    status: 'all',
    sortBy: 'writeDate',
    sortOrder: 'desc',
  });

  const updateFilter = useCallback((field: keyof FilterState, value: string) => {
    setFilters((prev) => ({ ...prev, [field]: value }));
  }, []);

  // 통계
  const totalSupply = records.reduce((sum, r) => sum + r.supplyAmount, 0);
  const totalTax = records.reduce((sum, r) => sum + r.taxAmount, 0);
  const totalAmount = records.reduce((sum, r) => sum + r.totalAmount, 0);

  const issuedCount = records.filter((r) => r.status === 'issued' || r.status === 'nts_sent').length;
  const sentCount = records.filter((r) => r.status === 'nts_sent').length;

  const stats = [
    {
      label: '발행건수',
      sublabel: `발행 ${issuedCount} / 전송 ${sentCount}`,
      value: `${totalAmount.toLocaleString('ko-KR')}원`,
      icon: Hash,
      iconColor: 'text-blue-600',
    },
    {
      label: '총 합계금액',
      value: `${totalAmount.toLocaleString('ko-KR')}원`,
      icon: Calculator,
      iconColor: 'text-green-600',
    },
    {
      label: '총 공급가액',
      value: `${totalSupply.toLocaleString('ko-KR')}원`,
      icon: DollarSign,
      iconColor: 'text-purple-600',
    },
    {
      label: '총 세액',
      value: `${totalTax.toLocaleString('ko-KR')}원`,
      icon: FileText,
      iconColor: 'text-orange-600',
    },
  ];

  // 세금계산서 발행 처리
  const handleSubmitInvoice = useCallback(
    async (data: TaxInvoiceFormData) => {
      const result = await createTaxInvoice(data);
      if (result.success && result.data) {
        setRecords((prev) => [result.data!, ...prev]);
        setShowNewForm(false);
        setSelectedVendor(null);
        toast.success('세금계산서가 발행되었습니다.');
      } else {
        toast.error(result.error || '발행에 실패했습니다.');
      }
    },
    []
  );

  // 거래처 선택 처리
  const handleVendorSelect = useCallback((vendor: VendorSearchItem) => {
    setSelectedVendor({
      businessNumber: vendor.businessNumber,
      companyName: vendor.companyName,
      representativeName: vendor.representativeName,
      address: vendor.address,
      businessType: vendor.businessType,
      businessItem: vendor.businessItem,
      contactName: vendor.contactName,
      contactPhone: vendor.contactPhone,
      contactEmail: vendor.contactEmail,
    });
    setShowVendorSearch(false);
  }, []);

  // 기간 단축 버튼
  const handleQuickDate = useCallback(
    (type: '1week' | '1month' | '3months') => {
      const today = new Date();
      const endDate = format(today, 'yyyy-MM-dd');
      let startDate: string;
      switch (type) {
        case '1week':
          startDate = format(subDays(today, 7), 'yyyy-MM-dd');
          break;
        case '1month':
          startDate = format(subMonths(today, 1), 'yyyy-MM-dd');
          break;
        case '3months':
          startDate = format(subMonths(today, 3), 'yyyy-MM-dd');
          break;
      }
      setFilters((prev) => ({ ...prev, startDate, endDate }));
    },
    []
  );

  const handleSearch = useCallback(() => {
    // TODO: 실제 API 연동 시 필터 조건으로 getTaxInvoices 호출
    toast.info('조회 기능은 API 연동 후 사용 가능합니다.');
  }, []);

  return (
    <PageLayout>
      <PageHeader
        title="세금계산서 발행"
        description="바로빌 API를 통하여 전자세금계산서를 발행하고 관리합니다"
        icon={FileText}
      />

      {/* 통계 카드 */}
      <StatCards stats={stats} />

      {/* 전자세금계산서 발행 섹션 */}
      <Card>
        <CardHeader className="flex flex-row items-center justify-between pb-4">
          <CardTitle className="text-base">전자세금계산서 발행</CardTitle>
          <div className="flex gap-2">
            <Button
              variant="outline"
              size="sm"
              onClick={() => setShowSupplierModal(true)}
            >
              <Settings className="h-4 w-4 mr-1" />
              공급자 설정
            </Button>
            <Button
              size="sm"
              onClick={() => setShowNewForm(!showNewForm)}
            >
              <PlusCircle className="h-4 w-4 mr-1" />
              {showNewForm ? '접기' : '새로 발행'}
            </Button>
          </div>
        </CardHeader>

        {showNewForm && (
          <CardContent className="pt-0">
            <TaxInvoiceForm
              supplier={supplierSettings}
              onSubmit={handleSubmitInvoice}
              onCancel={() => {
                setShowNewForm(false);
                setSelectedVendor(null);
              }}
              onVendorSearch={() => setShowVendorSearch(true)}
              selectedVendor={selectedVendor}
            />
          </CardContent>
        )}
      </Card>

      {/* 필터 */}
      <Card>
        <CardContent className="p-4 space-y-3">
          {/* Row1: 일자타입 + 날짜범위 + 기간 버튼 + 조회 */}
          <div className="flex flex-col lg:flex-row lg:items-center gap-2">
            <Select
              value={filters.dateType}
              onValueChange={(v) => updateFilter('dateType', v)}
            >
              <SelectTrigger className="w-full lg:w-[120px] h-9">
                <SelectValue />
              </SelectTrigger>
              <SelectContent>
                {DATE_TYPE_OPTIONS.map((opt) => (
                  <SelectItem key={opt.value} value={opt.value}>
                    {opt.label}
                  </SelectItem>
                ))}
              </SelectContent>
            </Select>

            <DateRangeSelector
              startDate={filters.startDate}
              endDate={filters.endDate}
              onStartDateChange={(v) => updateFilter('startDate', v)}
              onEndDateChange={(v) => updateFilter('endDate', v)}
              hidePresets
            />

            <div className="flex gap-1">
              <Button variant="outline" size="sm" onClick={() => handleQuickDate('1week')}>
                1주일
              </Button>
              <Button variant="outline" size="sm" onClick={() => handleQuickDate('1month')}>
                1개월
              </Button>
              <Button variant="outline" size="sm" onClick={() => handleQuickDate('3months')}>
                3개월
              </Button>
            </div>

            <Button size="sm" onClick={handleSearch}>
              조회
            </Button>
          </div>

          {/* Row2: 거래처 검색 */}
          <div className="relative max-w-md">
            <Search className="absolute left-3 top-1/2 -translate-y-1/2 h-4 w-4 text-muted-foreground" />
            <Input
              value={filters.vendorSearch}
              onChange={(e) => updateFilter('vendorSearch', e.target.value)}
              placeholder="사업자 번호 또는 사업자명"
              className="pl-9 h-9"
            />
          </div>

          {/* Row3: 상태 + 정렬 */}
          <div className="flex flex-col sm:flex-row gap-2">
            <Select
              value={filters.status}
              onValueChange={(v) => updateFilter('status', v)}
            >
              <SelectTrigger className="w-full sm:w-[130px] h-9">
                <SelectValue />
              </SelectTrigger>
              <SelectContent>
                {STATUS_OPTIONS.map((opt) => (
                  <SelectItem key={opt.value} value={opt.value}>
                    {opt.label}
                  </SelectItem>
                ))}
              </SelectContent>
            </Select>

            <Select
              value={filters.sortBy}
              onValueChange={(v) => updateFilter('sortBy', v)}
            >
              <SelectTrigger className="w-full sm:w-[130px] h-9">
                <SelectValue />
              </SelectTrigger>
              <SelectContent>
                {SORT_BY_OPTIONS.map((opt) => (
                  <SelectItem key={opt.value} value={opt.value}>
                    {opt.label}
                  </SelectItem>
                ))}
              </SelectContent>
            </Select>

            <Select
              value={filters.sortOrder}
              onValueChange={(v) => updateFilter('sortOrder', v)}
            >
              <SelectTrigger className="w-full sm:w-[130px] h-9">
                <SelectValue />
              </SelectTrigger>
              <SelectContent>
                {SORT_ORDER_OPTIONS.map((opt) => (
                  <SelectItem key={opt.value} value={opt.value}>
                    {opt.label}
                  </SelectItem>
                ))}
              </SelectContent>
            </Select>
          </div>
        </CardContent>
      </Card>

      {/* 테이블 */}
      <Card>
        <CardContent className="p-0">
          <div className="overflow-x-auto">
            <Table>
              <TableHeader>
                <TableRow>
                  <TableHead className="w-[40px] text-center">
                    <Checkbox
                      checked={records.length > 0 && selectedIds.size === records.length}
                      onCheckedChange={(checked) => {
                        if (checked) {
                          setSelectedIds(new Set(records.map((r) => r.id)));
                        } else {
                          setSelectedIds(new Set());
                        }
                      }}
                    />
                  </TableHead>
                  <TableHead className="w-[50px] text-center">번호</TableHead>
                  <TableHead className="min-w-[120px]">발행번호</TableHead>
                  <TableHead className="min-w-[120px]">공급받는자</TableHead>
                  <TableHead className="w-[100px] text-center">작성일자</TableHead>
                  <TableHead className="w-[100px] text-center">전송일자</TableHead>
                  <TableHead className="w-[110px] text-right">공급가액</TableHead>
                  <TableHead className="w-[100px] text-right">세액</TableHead>
                  <TableHead className="w-[110px] text-right">합계금액</TableHead>
                  <TableHead className="w-[90px] text-center">상태</TableHead>
                </TableRow>
              </TableHeader>
              <TableBody>
                {records.length > 0 ? (
                  records.map((record, index) => {
                    const statusInfo = TAX_INVOICE_STATUS_MAP[record.status];
                    return (
                      <TableRow
                        key={record.id}
                        className="cursor-pointer hover:bg-muted/50"
                        onClick={() => router.push(`?mode=edit&id=${record.id}`)}
                      >
                        <TableCell className="text-center" onClick={(e) => e.stopPropagation()}>
                          <Checkbox
                            checked={selectedIds.has(record.id)}
                            onCheckedChange={(checked) => {
                              setSelectedIds((prev) => {
                                const next = new Set(prev);
                                if (checked) next.add(record.id);
                                else next.delete(record.id);
                                return next;
                              });
                            }}
                          />
                        </TableCell>
                        <TableCell className="text-center">{index + 1}</TableCell>
                        <TableCell className="font-medium">{record.invoiceNumber}</TableCell>
                        <TableCell>{record.vendorName}</TableCell>
                        <TableCell className="text-center">{record.writeDate}</TableCell>
                        <TableCell className="text-center">{record.sendDate || '-'}</TableCell>
                        <TableCell className="text-right">
                          {record.supplyAmount.toLocaleString('ko-KR')}
                        </TableCell>
                        <TableCell className="text-right">
                          {record.taxAmount.toLocaleString('ko-KR')}
                        </TableCell>
                        <TableCell className="text-right font-medium">
                          {record.totalAmount.toLocaleString('ko-KR')}
                        </TableCell>
                        <TableCell className="text-center">
                          <span
                            className={`inline-flex items-center px-2 py-0.5 rounded-full text-xs font-medium ${statusInfo.color}`}
                          >
                            {statusInfo.label}
                          </span>
                        </TableCell>
                      </TableRow>
                    );
                  })
                ) : (
                  <TableRow>
                    <TableCell colSpan={10}>
                      <EmptyState
                        message="해당 조건에 맞는 세금계산서가 없습니다."
                        variant="compact"
                      />
                    </TableCell>
                  </TableRow>
                )}
              </TableBody>
            </Table>
          </div>
        </CardContent>
      </Card>

      {/* 공급자 설정 모달 */}
      <SupplierSettingModal
        open={showSupplierModal}
        onOpenChange={setShowSupplierModal}
        settings={supplierSettings}
        onSaved={setSupplierSettings}
      />

      {/* 거래처 검색 모달 */}
      <SearchableSelectionModal<VendorSearchItem>
        open={showVendorSearch}
        onOpenChange={setShowVendorSearch}
        title="거래처 검색"
        searchPlaceholder="거래처명, 사업자번호, 담당자명"
        fetchData={searchVendorsForTaxInvoice}
        keyExtractor={(item) => item.id}
        mode="single"
        onSelect={handleVendorSelect}
        searchMode="enter"
        dialogClassName="sm:max-w-xl"
        listContainerClassName="max-h-[400px] overflow-y-auto border rounded-md"
        noResultMessage="거래처가 없습니다."
        emptyQueryMessage="거래처명 또는 사업자번호를 입력하세요."
        listWrapper={(children) => (
          <div>
            <div className="grid grid-cols-2 border-b border-gray-300 bg-gray-100 font-semibold text-sm text-center">
              <div className="px-4 py-2 border-r border-gray-300">거래처명</div>
              <div className="px-4 py-2">사업자번호</div>
            </div>
            {children}
          </div>
        )}
        renderItem={(item) => (
          <div className="grid grid-cols-2 border-b border-gray-200 hover:bg-muted/50 text-sm">
            <div className="px-4 py-2.5 border-r border-gray-200 text-center">{item.companyName}</div>
            <div className="px-4 py-2.5 text-center">{item.businessNumber}</div>
          </div>
        )}
      />
    </PageLayout>
  );
}