package org.opentrafficsim.road.gtu.lane.tactical.util.lmrs;
   
   import java.util.HashMap;
   import java.util.HashSet;
   import java.util.Map;
   import java.util.Set;
   
   import org.opentrafficsim.road.gtu.animation.DesireBased;
   import org.opentrafficsim.road.gtu.animation.Synchronizable;
  import org.opentrafficsim.road.gtu.lane.LaneBasedGTU;
  import org.opentrafficsim.road.gtu.lane.perception.PerceptionCollectable;
  import org.opentrafficsim.road.gtu.lane.perception.headway.HeadwayGTU;
  
  /**
   * Keeps data for LMRS for a specific GTU.
   * <p>
   * Copyright (c) 2013-2018 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 8 nov. 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 final class LmrsData implements DesireBased, Synchronizable
  {
  
      /** Form of synchronization. */
      private final Synchronization synchronization;
  
      /** Form of cooperation. */
      private final Cooperation cooperation;
  
      /** Form of gap-acceptance. */
      private final GapAcceptance gapAcceptance;
  
      /** Form of tail gating. */
      private final Tailgating tailGating;
  
      /** Most recent leaders. */
      private final Set<String> leaders = new HashSet<>();
  
      /** Current leaders. */
      private final Set<String> tempLeaders = new HashSet<>();
  
      /** Latest desire value for visualization. */
      final Map<Class<? extends Incentive>, Desire> desireMap = new HashMap<>();
  
      /** Synchronization state. */
      State synchronizationState;
  
      /** Vehicle that is being synchronized to. */
      private String syncVehicle;
  
      /**
       * @param synchronization synchronization
       * @param cooperation cooperation
       * @param gapAcceptance gap-acceptance
       * @param tailGating tail gating
       */
      public LmrsData(final Synchronization synchronization, final Cooperation cooperation, final GapAcceptance gapAcceptance,
              final Tailgating tailGating)
      {
          this.synchronization = synchronization;
          this.cooperation = cooperation;
          this.gapAcceptance = gapAcceptance;
          this.tailGating = tailGating;
      }
  
      /**
       * Checks if the given leader is a new leader.
       * @param gtu gtu to check
       * @return whether the gtu is a new leader
       */
      boolean isNewLeader(final HeadwayGTU gtu)
      {
          this.tempLeaders.add(gtu.getId());
          return !this.leaders.contains(gtu.getId());
      }
  
      /**
       * Remembers the leaders of the current time step (those forwarded to isNewLeader()) for the next time step.
       */
      void finalizeStep()
      {
          this.leaders.clear();
          this.leaders.addAll(this.tempLeaders);
          this.tempLeaders.clear();
      }
  
      /**
       * Remembers the gtu that is synchronized to.
       * @param gtu gtu that is synchronized to
       */
      void setSyncVehicle(final HeadwayGTU gtu)
      {
          this.syncVehicle = gtu == null ? null : gtu.getId();
      }
  
     /**
      * Returns whether the provided gtu is the gtu that is synchronized to.
      * @param gtu gtu to inquiry
      * @return whether the provided gtu is the gtu that is synchronized to
      */
     boolean isSyncVehicle(final HeadwayGTU gtu)
     {
         return this.syncVehicle == null ? false : gtu.getId().equals(this.syncVehicle);
     }
 
     /**
      * Returns the gtu from the set that is the current sync vehicle, or {@code null} of there is no sync vehicle or it is not
      * in the set.
      * @param adjLeaders leaders in adjacent lane
      * @return gtu from the set that is the current sync vehicle
      */
     HeadwayGTU getSyncVehicle(final PerceptionCollectable<HeadwayGTU, LaneBasedGTU> adjLeaders)
     {
         if (this.syncVehicle == null)
         {
             return null;
         }
         for (HeadwayGTU leader : adjLeaders)
         {
             if (leader.getId().equals(this.syncVehicle))
             {
                 return leader;
             }
         }
         return null;
     }
 
     /**
      * Returns the synchronization.
      * @return synchronization
      */
     Synchronization getSynchronization()
     {
         return this.synchronization;
     }
 
     /**
      * Returns the cooperation.
      * @return cooperation
      */
     Cooperation getCooperation()
     {
         return this.cooperation;
     }
 
     /**
      * Return the gap-acceptance.
      * @return gap-acceptance
      */
     GapAcceptance getGapAcceptance()
     {
         return this.gapAcceptance;
     }
     
     /**
      * Return the tail gating.
      * @return gap-acceptance
      */
     Tailgating getTailGating()
     {
         return this.tailGating;
     }
 
     /** {@inheritDoc} */
     @Override
     public Desire getLatestDesire(final Class<? extends Incentive> incentiveClass)
     {
         return this.desireMap.get(incentiveClass);
     }
 
     /** {@inheritDoc} */
     @Override
     public State getSynchronizationState()
     {
         return this.synchronizationState;
     }
 
     /** {@inheritDoc} */
     @Override
     public String toString()
     {
         return "LmrsData [synchronization=" + this.synchronization + ", leaders=" + this.leaders + ", tempLeaders="
                 + this.tempLeaders + ", syncVehicle=" + this.syncVehicle + "]";
     }
 
 }