package org.opentrafficsim.road.network.lane;
   
   import java.io.Serializable;
   
   import org.djunits.value.vdouble.scalar.Length;
   import org.djutils.exceptions.Throw;
   import org.opentrafficsim.core.geometry.DirectedPoint;
   import org.opentrafficsim.core.geometry.OtsLine3d;
   
  /**
   * Store one position and lane of a GTU.
   * <p>
   * Copyright (c) 2013-2023 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/license.html">OpenTrafficSim License</a>.
   * </p>
   * @author <a href="https://github.com/averbraeck">Alexander Verbraeck</a>
   * @author <a href="https://tudelft.nl/staff/p.knoppers-1">Peter Knoppers</a>
   * @author <a href="https://dittlab.tudelft.nl">Wouter Schakel</a>
   */
  public class LanePosition implements Serializable
  {
      /** */
      private static final long serialVersionUID = 20151111L;
  
      /** The lane for the position. */
      private final Lane lane;
  
      /** The position on the lane, relative to the cross section link (design line). */
      private final Length position;
  
      /**
       * Construct a new LanePosition.
       * @param lane Lane; the lane for the position
       * @param position Length; the position on the lane, relative to the cross section link (design line) line, or against it
       */
      public LanePosition(final Lane lane, final Length position)
      {
          Throw.whenNull(lane, "lane is null");
          Throw.whenNull(position, "position is null");
          this.lane = lane;
          this.position = position;
      }
  
      /**
       * Retrieve the lane.
       * @return Lane; the lane for the position
       */
      public final Lane getLane()
      {
          return this.lane;
      }
  
      /**
       * Retrieve the position on the lane.
       * @return Length; the position on the lane, relative to the cross section link (design line)
       */
      public final Length getPosition()
      {
          return this.position;
      }
  
      /**
       * Retrieve the location and direction of the GTU on the lane.
       * @return DirectedPoint; the location and direction of the GTU on the lane
       */
      public final DirectedPoint getLocation()
      {
          // double fraction = this.position.si / this.lane.getParentLink().getLength().si;
          OtsLine3d centerLine = this.lane.getCenterLine();
          double centerLineLength = centerLine.getLengthSI();
          double fraction = this.position.si / centerLineLength;
          return centerLine.getLocationFractionExtended(fraction);
      }
  
      /** {@inheritDoc} */
      @Override
      public int hashCode()
      {
          final int prime = 31;
          int result = 1;
          result = prime * result + ((this.lane == null) ? 0 : this.lane.hashCode());
          result = prime * result + ((this.position == null) ? 0 : this.position.hashCode());
          return result;
      }
  
      /** {@inheritDoc} */
      @SuppressWarnings("checkstyle:needbraces")
      @Override
      public boolean equals(final Object obj)
      {
          if (this == obj)
              return true;
          if (obj == null)
              return false;
          if (getClass() != obj.getClass())
              return false;
          LanePosition other = (LanePosition) obj;
          if (this.lane == null)
          {
             if (other.lane != null)
                 return false;
         }
         else if (!this.lane.equals(other.lane))
             return false;
         if (this.position == null)
         {
             if (other.position != null)
                 return false;
         }
         else if (!this.position.equals(other.position))
             return false;
         return true;
     }
 
     /** {@inheritDoc} */
     @Override
     public final String toString()
     {
         return "LanePosition [lane=" + this.lane + ", position=" + this.position + "]";
     }
 
 }