gc-wing/apps/web/src/entities/vesselTrack/lib/buildTrackGeoJson.ts

import { haversineNm } from '../../../shared/lib/geo/haversineNm';
import type { ActiveTrack, NormalizedTrip } from '../model/types';

/** 시간순 정렬 후 TripsLayer용 정규화 데이터 생성 */
export function normalizeTrip(
  track: ActiveTrack,
  color: [number, number, number],
): NormalizedTrip {
  const sorted = [...track.points].sort(
    (a, b) => new Date(a.messageTimestamp).getTime() - new Date(b.messageTimestamp).getTime(),
  );

  if (sorted.length === 0) {
    return { path: [], timestamps: [], mmsi: track.mmsi, name: '', color };
  }

  const baseEpoch = new Date(sorted[0].messageTimestamp).getTime();
  const path: [number, number][] = [];
  const timestamps: number[] = [];

  for (const pt of sorted) {
    path.push([pt.lon, pt.lat]);
    // 32-bit float 정밀도를 보장하기 위해 첫 포인트 기준 초 단위 오프셋
    timestamps.push((new Date(pt.messageTimestamp).getTime() - baseEpoch) / 1000);
  }

  return {
    path,
    timestamps,
    mmsi: track.mmsi,
    name: sorted[0].name || `MMSI ${track.mmsi}`,
    color,
  };
}

/** Globe 전용 — LineString GeoJSON */
export function buildTrackLineGeoJson(
  track: ActiveTrack,
): GeoJSON.FeatureCollection<GeoJSON.LineString> {
  const sorted = [...track.points].sort(
    (a, b) => new Date(a.messageTimestamp).getTime() - new Date(b.messageTimestamp).getTime(),
  );

  if (sorted.length < 2) {
    return { type: 'FeatureCollection', features: [] };
  }

  let totalDistanceNm = 0;
  const coordinates: [number, number][] = [];
  for (let i = 0; i < sorted.length; i++) {
    const pt = sorted[i];
    coordinates.push([pt.lon, pt.lat]);
    if (i > 0) {
      const prev = sorted[i - 1];
      totalDistanceNm += haversineNm(prev.lat, prev.lon, pt.lat, pt.lon);
    }
  }

  return {
    type: 'FeatureCollection',
    features: [
      {
        type: 'Feature',
        properties: {
          mmsi: track.mmsi,
          name: sorted[0].name || `MMSI ${track.mmsi}`,
          pointCount: sorted.length,
          minutes: track.minutes,
          totalDistanceNm: Math.round(totalDistanceNm * 100) / 100,
        },
        geometry: { type: 'LineString', coordinates },
      },
    ],
  };
}

/** Globe+Mercator 공용 — Point GeoJSON */
export function buildTrackPointsGeoJson(
  track: ActiveTrack,
): GeoJSON.FeatureCollection<GeoJSON.Point> {
  const sorted = [...track.points].sort(
    (a, b) => new Date(a.messageTimestamp).getTime() - new Date(b.messageTimestamp).getTime(),
  );

  return {
    type: 'FeatureCollection',
    features: sorted.map((pt, index) => ({
      type: 'Feature' as const,
      properties: {
        mmsi: pt.mmsi,
        name: pt.name,
        sog: pt.sog,
        cog: pt.cog,
        heading: pt.heading,
        status: pt.status,
        messageTimestamp: pt.messageTimestamp,
        index,
      },
      geometry: { type: 'Point' as const, coordinates: [pt.lon, pt.lat] },
    })),
  };
}

export function getTrackTimeRange(trip: NormalizedTrip): {
  minTime: number;
  maxTime: number;
  durationSec: number;
} {
  if (trip.timestamps.length === 0) {
    return { minTime: 0, maxTime: 0, durationSec: 0 };
  }
  const minTime = trip.timestamps[0];
  const maxTime = trip.timestamps[trip.timestamps.length - 1];
  return { minTime, maxTime, durationSec: maxTime - minTime };
}