import { useState, useEffect, useCallback, useMemo } from 'react';
import { useTranslation } from 'react-i18next';
import { Badge } from '@shared/components/ui/badge';
import { Button } from '@shared/components/ui/button';
import { Select } from '@shared/components/ui/select';
import { PageContainer, PageHeader } from '@shared/components/layout';
import { DataTable, type DataColumn } from '@shared/components/common/DataTable';
import { FileUpload } from '@shared/components/common/FileUpload';
import {
  AlertTriangle, Eye, Anchor, Radar, Crosshair,
  Filter, Upload, X, Loader2,
} from 'lucide-react';
import { useEventStore } from '@stores/eventStore';
import { formatDateTime } from '@shared/utils/dateFormat';
import { type AlertLevel as AlertLevelType, getAlertLevelLabel, getAlertLevelIntent } from '@shared/constants/alertLevels';
import { getEventStatusIntent, getEventStatusLabel } from '@shared/constants/eventStatuses';
import { getViolationLabel, getViolationIntent } from '@shared/constants/violationTypes';
import { useSettingsStore } from '@stores/settingsStore';

/*
 * 이벤트 목록 — SFR-02 공통컴포넌트 적용
 * DataTable(검색+정렬+페이징+엑셀내보내기+출력), FileUpload
 * 실제 백엔드 API 연동
 */

type AlertLevel = AlertLevelType;

interface EventRow {
  id: string;
  time: string;
  level: AlertLevel;
  type: string;
  vesselName: string;
  mmsi: string;
  area: string;
  lat: string;
  lng: string;
  speed: string;
  status: string;
  assignee: string;
  [key: string]: unknown;
}

export function EventList() {
  const { t } = useTranslation('enforcement');
  const { t: tc } = useTranslation('common');
  const lang = useSettingsStore((s) => s.language);
  const {
    events: storeEvents,
    stats,
    loading,
    error,
    load,
    loadStats,
  } = useEventStore();

  const columns: DataColumn<EventRow>[] = useMemo(() => [
    {
      key: 'level', label: '등급', minWidth: '64px', maxWidth: '110px', sortable: true,
      render: (val) => {
        const lv = val as AlertLevel;
        return (
          <Badge intent={getAlertLevelIntent(lv)} size="sm">
            {getAlertLevelLabel(lv, tc, lang)}
          </Badge>
        );
      },
    },
    { key: 'time', label: '발생시간', minWidth: '140px', maxWidth: '170px', sortable: true,
      render: (val) => <span className="text-muted-foreground font-mono text-[10px]">{formatDateTime(val as string)}</span>,
    },
    { key: 'type', label: '유형', minWidth: '90px', maxWidth: '160px', sortable: true,
      render: (val) => {
        const code = val as string;
        return (
          <Badge intent={getViolationIntent(code)} size="sm">
            {getViolationLabel(code, tc, lang)}
          </Badge>
        );
      },
    },
    { key: 'vesselName', label: '선박명', minWidth: '100px', maxWidth: '220px', sortable: true,
      render: (val) => <span className="text-cyan-400 font-medium">{val as string}</span>,
    },
    { key: 'mmsi', label: 'MMSI', minWidth: '90px', maxWidth: '120px',
      render: (val) => <span className="text-hint font-mono text-[10px]">{val as string}</span>,
    },
    { key: 'area', label: '해역', minWidth: '80px', maxWidth: '140px', sortable: true },
    { key: 'speed', label: '속력', minWidth: '56px', maxWidth: '80px', align: 'right' },
    {
      key: 'status', label: '처리상태', minWidth: '80px', maxWidth: '120px', sortable: true,
      render: (val) => {
        const s = val as string;
        return (
          <Badge intent={getEventStatusIntent(s)} size="xs">
            {getEventStatusLabel(s, tc, lang)}
          </Badge>
        );
      },
    },
    { key: 'assignee', label: '담당', minWidth: '60px', maxWidth: '100px' },
  ], [tc, lang]);

  const [levelFilter, setLevelFilter] = useState<string>('');
  const [showUpload, setShowUpload] = useState(false);

  const fetchData = useCallback(() => {
    const params = levelFilter ? { level: levelFilter } : undefined;
    load(params);
    loadStats();
  }, [levelFilter, load, loadStats]);

  useEffect(() => {
    fetchData();
  }, [fetchData]);

  // store events -> EventRow 변환
  const EVENTS: EventRow[] = storeEvents.map((e) => ({
    id: e.id,
    time: e.time,
    level: e.level as AlertLevel,
    type: e.type,
    vesselName: e.vesselName ?? '-',
    mmsi: e.mmsi ?? '-',
    area: e.area ?? '-',
    lat: e.lat != null ? String(e.lat) : '-',
    lng: e.lng != null ? String(e.lng) : '-',
    speed: e.speed != null ? `${e.speed}kt` : '미상',
    status: e.status ?? '-',
    assignee: e.assignee ?? '-',
  }));

  // KPI 카운트: stats API가 있으면 사용, 없으면 클라이언트 계산
  const kpiCritical = stats['CRITICAL'] ?? EVENTS.filter((e) => e.level === 'CRITICAL').length;
  const kpiHigh = stats['HIGH'] ?? EVENTS.filter((e) => e.level === 'HIGH').length;
  const kpiMedium = stats['MEDIUM'] ?? EVENTS.filter((e) => e.level === 'MEDIUM').length;
  const kpiLow = stats['LOW'] ?? EVENTS.filter((e) => e.level === 'LOW').length;
  const kpiTotal = (stats['TOTAL'] as number | undefined) ?? EVENTS.length;

  return (
    <PageContainer>
      <PageHeader
        icon={Radar}
        iconColor="text-blue-400"
        title={t('eventList.title')}
        description={t('eventList.desc')}
        actions={
          <>
            <div className="flex items-center gap-1">
              <Filter className="w-3.5 h-3.5 text-hint" />
              <Select
                size="sm"
                value={levelFilter}
                onChange={(e) => setLevelFilter(e.target.value)}
                title="등급 필터"
                className="w-32"
              >
                <option value="">전체 등급</option>
                <option value="CRITICAL">CRITICAL</option>
                <option value="HIGH">HIGH</option>
                <option value="MEDIUM">MEDIUM</option>
                <option value="LOW">LOW</option>
              </Select>
            </div>
            <Button
              variant="secondary"
              size="sm"
              onClick={() => setShowUpload(!showUpload)}
              icon={<Upload className="w-3 h-3" />}
            >
              파일 업로드
            </Button>
          </>
        }
      />

      {/* KPI 요약 */}
      <div className="grid grid-cols-5 gap-3">
        {[
          { label: '전체', count: kpiTotal, icon: Radar, color: 'text-label', bg: 'bg-muted', filterVal: '' },
          { label: 'CRITICAL', count: kpiCritical, icon: AlertTriangle, color: 'text-red-400', bg: 'bg-red-500/10', filterVal: 'CRITICAL' },
          { label: 'HIGH', count: kpiHigh, icon: Eye, color: 'text-orange-400', bg: 'bg-orange-500/10', filterVal: 'HIGH' },
          { label: 'MEDIUM', count: kpiMedium, icon: Anchor, color: 'text-yellow-400', bg: 'bg-yellow-500/10', filterVal: 'MEDIUM' },
          { label: 'LOW', count: kpiLow, icon: Crosshair, color: 'text-blue-400', bg: 'bg-blue-500/10', filterVal: 'LOW' },
        ].map((kpi) => (
          <div
            key={kpi.label}
            onClick={() => setLevelFilter(kpi.filterVal)}
            className={`flex items-center gap-2.5 p-3 rounded-xl border cursor-pointer transition-colors ${
              (kpi.filterVal === '' && !levelFilter) || kpi.filterVal === levelFilter
                ? 'bg-card border-blue-500/30'
                : 'bg-card border-border hover:border-border'
            }`}
          >
            <div className={`p-1.5 rounded-lg ${kpi.bg}`}>
              <kpi.icon className={`w-4 h-4 ${kpi.color}`} />
            </div>
            <div>
              <div className={`text-lg font-bold ${kpi.color}`}>{kpi.count}</div>
              <div className="text-[9px] text-hint">{kpi.label}</div>
            </div>
          </div>
        ))}
      </div>

      {/* 에러 표시 */}
      {error && (
        <div className="rounded-xl border border-red-500/30 bg-red-500/10 p-3 text-[11px] text-red-400">
          데이터 로딩 실패: {error}
        </div>
      )}

      {/* 파일 업로드 영역 */}
      {showUpload && (
        <div className="rounded-xl border border-border bg-card p-4">
          <div className="flex items-center justify-between mb-2">
            <span className="text-[11px] text-label font-bold">이벤트 데이터 업로드</span>
            <button type="button" title="닫기" onClick={() => setShowUpload(false)} className="text-hint hover:text-muted-foreground">
              <X className="w-4 h-4" />
            </button>
          </div>
          <FileUpload
            accept=".xlsx,.csv"
            multiple
            maxSizeMB={20}
            onFilesSelected={(files) => console.log('Uploaded:', files)}
          />
        </div>
      )}

      {/* 로딩 인디케이터 */}
      {loading && (
        <div className="flex items-center justify-center py-8">
          <Loader2 className="w-5 h-5 text-blue-400 animate-spin" />
          <span className="ml-2 text-[11px] text-muted-foreground">로딩 중...</span>
        </div>
      )}

      {/* DataTable — 검색+정렬+페이징+엑셀+출력 */}
      {!loading && (
        <DataTable
          data={EVENTS}
          columns={columns}
          pageSize={10}
          searchPlaceholder="이벤트ID, 선박명, MMSI, 해역 검색..."
          searchKeys={['id', 'vesselName', 'mmsi', 'area', 'type']}
          exportFilename="이벤트목록"
        />
      )}
    </PageContainer>
  );
}