package org.opentrafficsim.kpi.sampling.indicator;
   
   import java.util.List;
   
   import org.djunits.unit.DurationUnit;
   import org.djunits.value.vdouble.scalar.Duration;
   import org.djunits.value.vdouble.scalar.Time;
   import org.opentrafficsim.kpi.interfaces.GtuDataInterface;
   import org.opentrafficsim.kpi.sampling.Query;
  import org.opentrafficsim.kpi.sampling.TrajectoryGroup;
  
  /**
   * Inverse of mean speed.
   * <p>
   * Copyright (c) 2013-2019 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
   * BSD-style license. See <a href="http://opentrafficsim.org/node/13">OpenTrafficSim License</a>.
   * <p>
   * @version $Revision$, $LastChangedDate$, by $Author$, initial version 1 okt. 2016 <br>
   * @author <a href="http://www.tbm.tudelft.nl/averbraeck">Alexander Verbraeck</a>
   * @author <a href="http://www.tudelft.nl/pknoppers">Peter Knoppers</a>
   * @author <a href="http://www.transport.citg.tudelft.nl">Wouter Schakel</a>
   */
  public class MeanTravelTimePerDistance extends AbstractIndicator<Duration>
  {
  
      /** Mean speed indicator. */
      private final MeanSpeed meanSpeed;
  
      /**
       * @param meanSpeed MeanSpeed; mean speed indicator
       */
      public MeanTravelTimePerDistance(final MeanSpeed meanSpeed)
      {
          this.meanSpeed = meanSpeed;
      }
  
      /** {@inheritDoc} */
      @Override
      protected <G extends GtuDataInterface> Duration calculate(final Query<G> query, final Time startTime, final Time endTime,
              final List<TrajectoryGroup<G>> trajectoryGroups)
      {
          return new Duration(1.0 / this.meanSpeed.getValue(query, startTime, endTime, trajectoryGroups).si, DurationUnit.SI);
      }
  
      /** {@inheritDoc} */
      @Override
      @SuppressWarnings("checkstyle:designforextension")
      public String toString()
      {
          return "MeanTravelTime [meanTravelTime=" + this.meanSpeed + " (per km)]";
      }
  
  }