gernotbelger@8850: /** Copyright (C) 2017 by Bundesanstalt für Gewässerkunde
gernotbelger@8850:  * Software engineering by 
gernotbelger@8850:  *  Björnsen Beratende Ingenieure GmbH 
gernotbelger@8850:  *  Dr. Schumacher Ingenieurbüro für Wasser und Umwelt
gernotbelger@8850:  *
gernotbelger@8850:  * This file is Free Software under the GNU AGPL (>=v3)
gernotbelger@8850:  * and comes with ABSOLUTELY NO WARRANTY! Check out the
gernotbelger@8850:  * documentation coming with Dive4Elements River for details.
gernotbelger@8850:  */
gernotbelger@8850: package org.dive4elements.river.utils;
gernotbelger@8850: 
gernotbelger@8850: import java.util.List;
gernotbelger@8850: 
gernotbelger@8850: import org.dive4elements.river.model.Gauge;
gernotbelger@8850: 
gernotbelger@8850: /**
gernotbelger@8850:  * Allows performant access to gauges by station.
gernotbelger@8850:  * @author Gernot Belger
gernotbelger@8850:  */
gernotbelger@8850: public class GaugeIndex {
gernotbelger@8850: 	private List<Gauge> gauges;
gernotbelger@8850: 	
gernotbelger@8850: 	private Gauge lastGauge = null;
gernotbelger@8850: 
gernotbelger@8850: 	public GaugeIndex( List<Gauge> gauges) {
gernotbelger@8850: 		this.gauges = gauges;
gernotbelger@8850: 	}
gernotbelger@8850: 	
gernotbelger@8850: 	public Gauge findGauge(double km) {
gernotbelger@8850: 
gernotbelger@8850: 		// REMARK: this is code copied from WaterlevelExporter, which is honestly not very fast/good.
gernotbelger@8850: 		// Instead we need to index by range with an RTree and directly acccess the right gauge.
gernotbelger@8850: 		
gernotbelger@8850: 		if( lastGauge != null && lastGauge.getRange().contains(km) )
gernotbelger@8850: 			return lastGauge;
gernotbelger@8850: 		
gernotbelger@8850: 		final Gauge gauge = findGauge(km, gauges);
gernotbelger@8850: 
gernotbelger@8850:         lastGauge = gauge;
gernotbelger@8850:             
gernotbelger@8850:         return gauge;
gernotbelger@8850: 	}
gernotbelger@8850: 	
gernotbelger@8850:     private static Gauge findGauge(double km, List<Gauge> gauges) {
gernotbelger@8850:         for (Gauge gauge: gauges) {
gernotbelger@8850:             if (gauge.getRange().contains(km)) {
gernotbelger@8850:                 return gauge;
gernotbelger@8850:             }
gernotbelger@8850:         }
gernotbelger@8850:         return null;
gernotbelger@8850:     }
gernotbelger@8850: }