package org.opentrafficsim.road.network;

import static org.junit.Assert.assertEquals;

import org.djunits.unit.LengthUnit;
import org.djunits.unit.util.UNITS;
import org.djunits.value.vdouble.scalar.Length;
import org.djutils.draw.line.PolyLine3d;
import org.djutils.draw.point.Point3d;
import org.junit.Test;
import org.opentrafficsim.core.dsol.OTSSimulatorInterface;
import org.opentrafficsim.core.network.LinkPosition;
import org.opentrafficsim.core.network.LinkType;
import org.opentrafficsim.core.network.NetworkException;
import org.opentrafficsim.core.network.Node;
import org.opentrafficsim.road.mock.MockSimulator;
import org.opentrafficsim.road.network.defaults.RoadNetworkDefaults;
import org.opentrafficsim.road.network.lane.CrossSectionLink;
import org.opentrafficsim.road.network.lane.changing.LaneKeepingPolicy;

/**
 * Test the LinkPosition class.
 * <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="http://opentrafficsim.org/docs/license.html">OpenTrafficSim License</a>.
 * </p>
 * $LastChangedDate: 2015-09-16 19:20:07 +0200 (Wed, 16 Sep 2015) $, @version $Revision: 1405 $, by $Author: averbraeck $,
 * initial version 20 jan. 2015 <br>
 * @author <a href="https://www.tudelft.nl/pknoppers">Peter Knoppers</a>
 */
public class LinkPositionTest implements UNITS
{
    /**
     * Test constructor and verify all getters.
     * @throws NetworkException if that happens this test has failed
     */
    @Test
    public final void linkPositionTest() throws NetworkException
    {
        // Preparations
        OTSSimulatorInterface simulator = MockSimulator.createMock();
        RoadNetwork network = new RoadNetwork("link location test network", simulator);
        RoadNetworkDefaults.registerDefaults(network);
        Node nodeFrom = new Node(network, "From", new Point3d(0, 0, 0), 0.0);
        Node nodeTo = new Node(network, "To", new Point3d(1000, 0, 0), 0.0);
        PolyLine3d line = new PolyLine3d(new Point3d[] {new Point3d(0, 0, 0), new Point3d(1000, 0, 0)});
        CrossSectionLink link = new CrossSectionLink(network, "Link", nodeFrom, nodeTo,
                network.getLinkType(LinkType.DEFAULTS.ROAD), line, LaneKeepingPolicy.KEEPRIGHT);
        Length linkLength = new Length(line.getLength(), LengthUnit.SI);
        // Now we can make a LinkPosition.
        Length referenceLocationDistance = new Length(123, METER);
        LinkPosition referencePosition = new LinkPosition(link, referenceLocationDistance);
        assertEquals("link should be the provided Link", link, referencePosition.getLink());
        assertEquals("longitudinalPosition should be " + referenceLocationDistance, referenceLocationDistance.getSI(),
                referencePosition.getLongitudinalPosition().getSI(), 0.0001);
        for (int position = 0; position < 1000; position += 100)
        {
            final double fraction = position / linkLength.getSI();
            LinkPosition linkPosition = new LinkPosition(link, fraction);
            assertEquals("link should be the provided Link", link, linkPosition.getLink());
            assertEquals("fractionalLongitudinalPosition should be " + fraction, fraction,
                    linkPosition.getFractionalLongitudinalPosition(), 0.000001);
            assertEquals("longitudinalPosition should be " + position, position, linkPosition.getLongitudinalPosition().getSI(),
                    0.0001);
            // Repeat with the other constructor
            linkPosition = new LinkPosition(link, new Length(position, METER));
            assertEquals("link should be the provided Link", link, linkPosition.getLink());
            assertEquals("fractionalLongitudinalPosition should be " + fraction, fraction,
                    linkPosition.getFractionalLongitudinalPosition(), 0.000001);
            assertEquals("longitudinalPosition should be " + position, position, linkPosition.getLongitudinalPosition().getSI(),
                    0.0001);
            double delta = referenceLocationDistance.getSI() - position;
            assertEquals("distance from reference should be " + delta, delta, linkPosition.distance(referencePosition).getSI(),
                    0.0001);
            
            // TODO distance to location on another link (not yet possible; currently ALWAYS returns null)
        }
    }
}