kcg-monitoring/frontend/src/hooks/useGroupPolygons.ts

import { useState, useEffect, useRef, useMemo, useCallback } from 'react';
import { fetchGroupPolygons } from '../services/vesselAnalysis';
import type { GroupPolygonDto } from '../services/vesselAnalysis';

const POLL_INTERVAL_MS = 5 * 60_000; // 5분

export interface UseGroupPolygonsResult {
  fleetGroups: GroupPolygonDto[];
  gearInZoneGroups: GroupPolygonDto[];
  gearOutZoneGroups: GroupPolygonDto[];
  allGroups: GroupPolygonDto[];
  isLoading: boolean;
  lastUpdated: number;
}

const EMPTY: UseGroupPolygonsResult = {
  fleetGroups: [],
  gearInZoneGroups: [],
  gearOutZoneGroups: [],
  allGroups: [],
  isLoading: false,
  lastUpdated: 0,
};

export function useGroupPolygons(enabled: boolean): UseGroupPolygonsResult {
  const [allGroups, setAllGroups] = useState<GroupPolygonDto[]>([]);
  const [isLoading, setIsLoading] = useState(false);
  const [lastUpdated, setLastUpdated] = useState(0);
  const timerRef = useRef<ReturnType<typeof setInterval>>();

  const load = useCallback(async () => {
    setIsLoading(true);
    try {
      const groups = await fetchGroupPolygons();
      setAllGroups(groups);
      setLastUpdated(Date.now());
    } catch {
      // 네트워크 오류 시 기존 데이터 유지
    } finally {
      setIsLoading(false);
    }
  }, []);

  useEffect(() => {
    if (!enabled) return;
    load();
    timerRef.current = setInterval(load, POLL_INTERVAL_MS);
    return () => clearInterval(timerRef.current);
  }, [enabled, load]);

  const fleetGroups = useMemo(
    () => allGroups.filter(g => g.groupType === 'FLEET'),
    [allGroups],
  );

  const gearInZoneGroups = useMemo(
    () => allGroups.filter(g => g.groupType === 'GEAR_IN_ZONE'),
    [allGroups],
  );

  const gearOutZoneGroups = useMemo(
    () => allGroups.filter(g => g.groupType === 'GEAR_OUT_ZONE'),
    [allGroups],
  );

  if (!enabled) return EMPTY;

  return { fleetGroups, gearInZoneGroups, gearOutZoneGroups, allGroups, isLoading, lastUpdated };
}