import type { PropertyFeature, POIDistanceInfo } from '@/types';

/**
 * Build the flat property name used by the hexgrid heatmap to read
 * travel-time values directly from feature.properties.
 */
export function poiMetricPropertyName(poiId: number, travelMode: string): string {
  return `poi_travel_${poiId}_${travelMode}`;
}

/**
 * Shallow-copy every feature and inject a flat numeric property
 * (e.g. `poi_travel_7_TRANSIT = 1800`) so the heatmap can color by it.
 *
 * Features without matching POI distance data get `undefined` for that property,
 * which the heatmap will skip (same as a listing with no sqm value).
 */
export function injectPoiMetricProperty(
  features: PropertyFeature[],
  poiId: number,
  travelMode: string,
): PropertyFeature[] {
  const propName = poiMetricPropertyName(poiId, travelMode);

  return features.map((feature) => {
    const distances: POIDistanceInfo[] | undefined = feature.properties.poi_distances;
    const match = distances?.find(
      (d) => d.poi_id === poiId && d.travel_mode === travelMode,
    );

    if (match === undefined) return feature;

    return {
      ...feature,
      properties: {
        ...feature.properties,
        [propName]: match.duration_seconds,
      },
    };
  });
}