import {IGeoTransformStrategy} from './geo-transform-strategy.interface';
import {IRecord, RecordCollection} from '../record-collection';
import {IFeatureCollection} from '../../utility/feature-collection.interface';
import {FeatureIdService} from '../../utility/feature-id.service';
import * as turf from 'turf';

export class GeoJsonTransformStrategy implements IGeoTransformStrategy {
  private idService: FeatureIdService = new FeatureIdService();

  transform(record: IRecord, collection: RecordCollection): IFeatureCollection {

    const polygon = turf.polygon(record['geoJson'].coordinates, record);
    polygon.crs = record['geoJson'].crs;
    const point = turf.centroid(polygon);
    point.properties = record;
    return _([polygon, point])
      .filter(_.isObject)
      .map(this.idService.addFeatureId)
      .thru(features => turf.featurecollection(features))
      .value();
  }
}