Doroga — цифровая платформа логистики Центральной Азии

// Doroga (doroga.kg) · фрагмент исходного кода · автор: Музарбек Жолошев
// Какие пункты пропуска встречает грузовик на выбранной дороге — по порядку и с километром от начала маршрута.

const NEAR_KM = 10;   // how close a crossing must be to the road to count as on the route
const DEDUPE_KM = 60; // two crossings of the same border this close together are the same decision

/** The crossings a route passes through, in the order the truck meets them. */
export function crossingsOnRoute(geometry: string, totalKm?: number): LocatedCrossing[] {
  const points = decodePolyline(geometry);
  if (points.length < 2) return [];
  const { cumulative, scale } = measure(points, totalKm);

  const found: Located[] = [];
  for (const crossing of CROSSINGS) {
    const best = nearestOnLine([crossing.lat, crossing.lng], points, cumulative);
    if (best.km <= NEAR_KM) {
      found.push({ crossing, along: best.along, offKm: best.km });
    }
  }

  found.sort((a, b) => a.along - b.along);

  // Same border, same stretch of road: keep whichever sits closer to the line.
  const kept: Located[] = [];
  for (const item of found) {
    const rival = kept.findIndex(
      (k) =>
        Math.abs(k.along - item.along) < DEDUPE_KM && sameBorder(k.crossing, item.crossing),
    );
    if (rival === -1) kept.push(item);
    else if (item.offKm < kept[rival].offKm) kept[rival] = item;
  }
  kept.sort((a, b) => a.along - b.along);

  return kept.map(({ crossing, along }) => ({
    id: crossing.id,
    atKm: Math.round(along * scale),
  }));
}