package org.opentrafficsim.road;
   
   import org.djunits.value.vdouble.scalar.Acceleration;
   import org.djunits.value.vdouble.scalar.Length;
   import org.djunits.value.vdouble.scalar.Speed;
   import org.opentrafficsim.base.parameters.ParameterException;
   import org.opentrafficsim.base.parameters.ParameterSet;
   import org.opentrafficsim.base.parameters.Parameters;
   import org.opentrafficsim.core.gtu.GtuType;
  import org.opentrafficsim.road.FixedCarFollowing.FixedCarFollowingModel;
  import org.opentrafficsim.road.gtu.lane.perception.PerceptionIterable;
  import org.opentrafficsim.road.gtu.lane.perception.object.PerceivedObject;
  import org.opentrafficsim.road.gtu.lane.tactical.following.CarFollowingModel;
  import org.opentrafficsim.road.gtu.lane.tactical.following.CarFollowingModelFactory;
  import org.opentrafficsim.road.network.speed.SpeedLimitInfo;
  
  /**
   * Very simple car-following model factory only for testing.
   * <p>
   * Copyright (c) 2024-2024 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/wjschakel">Wouter Schakel</a>
   */
  public class FixedCarFollowing implements CarFollowingModelFactory<FixedCarFollowingModel>
  {
      /** Fixed acceleration. */
      private final Acceleration acceleration;
  
      /** Fixed desired speed. */
      private final Speed desiredSpeed;
  
      /** Fixed desired headway. */
      private final Length desiredHeadway;
  
      /**
       * Constructor.
       */
      public FixedCarFollowing()
      {
          this(Acceleration.ZERO, Speed.ONE, Length.ONE);
      }
  
      /**
       * Constructor.
       * @param acceleration fixed acceleration
       */
      public FixedCarFollowing(final Acceleration acceleration)
      {
          this(acceleration, Speed.ONE, Length.ONE);
      }
  
      /**
       * Constructor.
       * @param acceleration fixed acceleration
       * @param desiredSpeed fixed desired speed
       * @param desiredHeadway fixed desired headway
       */
      public FixedCarFollowing(final Acceleration acceleration, final Speed desiredSpeed, final Length desiredHeadway)
      {
          this.acceleration = acceleration;
          this.desiredHeadway = desiredHeadway;
          this.desiredSpeed = desiredSpeed;
      }
  
      @Override
      public Parameters getParameters(final GtuType gtuType) throws ParameterException
      {
          return new ParameterSet();
      }
  
      @Override
      public FixedCarFollowingModel get()
      {
          return new FixedCarFollowingModel();
      }
  
      /**
       * Fixed car-following model.
       */
      public class FixedCarFollowingModel implements CarFollowingModel
      {
  
          /**
           * Constructor.
           */
          public FixedCarFollowingModel()
          {
              //
          }
  
          @Override
          public Length desiredHeadway(final Parameters parameters, final Speed speed) throws ParameterException
          {
              return FixedCarFollowing.this.desiredHeadway;
          }
  
          @Override
          public Speed desiredSpeed(final Parameters parameters, final SpeedLimitInfo speedInfo) throws ParameterException
         {
             return FixedCarFollowing.this.desiredSpeed;
         }
 
         @Override
         public Acceleration followingAcceleration(final Parameters parameters, final Speed speed,
                 final SpeedLimitInfo speedLimitInfo, final PerceptionIterable<? extends PerceivedObject> leaders)
                 throws ParameterException
         {
             return FixedCarFollowing.this.acceleration;
         }
 
         @Override
         public String getName()
         {
             return "FixedAcceleration";
         }
 
         @Override
         public String getLongName()
         {
             return "FixedAcceleration";
         }
 
     }
 }