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) 2013-2021 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
 * BSD-style license. See <a href="https://opentrafficsim.org/docs/v2/license.html">OpenTrafficSim License</a>.
 * </p>
 * @version $Revision$, $LastChangedDate$, by $Author$, initial version 1 okt. 2016 <br>
 * @author <a href="https://www.tbm.tudelft.nl/averbraeck">Alexander Verbraeck</a>
 * @author <a href="https://www.tudelft.nl/pknoppers">Peter Knoppers</a>
 * @author <a href="https://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
    public String toString()
    {
        return "MeanTravelTime [meanTravelTime=" + this.meanSpeed + " (per km)]";
    }

}