package org.opentrafficsim.trafficcontrol;
   
   import java.rmi.RemoteException;
   import java.util.ArrayList;
   import java.util.LinkedHashSet;
   import java.util.List;
   import java.util.Set;
   
   import nl.tudelft.simulation.dsol.SimRuntimeException;
  import nl.tudelft.simulation.event.EventInterface;
  
  import org.djunits.value.vdouble.scalar.Duration;
  import org.djunits.value.vdouble.scalar.Time;
  import org.djutils.exceptions.Throw;
  import org.djutils.immutablecollections.Immutable;
  import org.djutils.immutablecollections.ImmutableArrayList;
  import org.djutils.immutablecollections.ImmutableCollections;
  import org.djutils.immutablecollections.ImmutableHashSet;
  import org.djutils.immutablecollections.ImmutableList;
  import org.djutils.immutablecollections.ImmutableMap;
  import org.djutils.immutablecollections.ImmutableSet;
  import org.opentrafficsim.base.Identifiable;
  import org.opentrafficsim.core.dsol.OTSSimulatorInterface;
  import org.opentrafficsim.core.network.Network;
  import org.opentrafficsim.core.network.NetworkException;
  import org.opentrafficsim.core.object.InvisibleObjectInterface;
  import org.opentrafficsim.road.network.lane.object.trafficlight.TrafficLight;
  import org.opentrafficsim.road.network.lane.object.trafficlight.TrafficLightColor;
  
  /**
   * Fixed time traffic light control.
   * <p>
   * Copyright (c) 2013-2019 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 21 feb. 2019 <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 class FixedTimeController extends AbstractTrafficController
  {
  
      /** */
      private static final long serialVersionUID = 20190221L;
  
      /** Cycle time. */
      private final Duration cycleTime;
  
      /** Offset. */
      private final Duration offset;
  
      /** Signal groups, for cloning. */
      private final Set<SignalGroup> signalGroups;
  
      /**
       * Constructor for fixed time traffic controller.
       * @param id String; id
       * @param simulator OTSSimulatorInterface; simulator
       * @param network Network; network
       * @param offset Duration; off set from simulation start time
       * @param cycleTime Duration; cycle time
       * @param signalGroups Set&lt;SignalGroup&gt;; signal groups
       * @throws SimRuntimeException simulator is past zero time
       */
      @SuppressWarnings({ "synthetic-access" })
      public FixedTimeController(final String id, final OTSSimulatorInterface simulator, final Network network,
              final Duration cycleTime, final Duration offset, final Set<SignalGroup> signalGroups) throws SimRuntimeException
      {
          super(id, simulator);
          Throw.whenNull(simulator, "Simulator may not be null.");
          Throw.whenNull(network, "Network may not be null.");
          Throw.whenNull(cycleTime, "Cycle time may not be null.");
          Throw.whenNull(offset, "Offset may not be null.");
          Throw.whenNull(signalGroups, "Signal groups may not be null.");
          Throw.when(cycleTime.le0(), IllegalArgumentException.class, "Cycle time must be positive.");
          Throw.when(signalGroups.isEmpty(), IllegalArgumentException.class, "Signal groups may not be empty.");
          for (SignalGroup signalGroup1 : signalGroups)
          {
              for (SignalGroup signalGroup2 : signalGroups)
              {
                  if (!signalGroup1.equals(signalGroup2))
                  {
                      Throw.when(!ImmutableCollections.disjoint(signalGroup1.trafficLightIds, signalGroup2.trafficLightIds),
                              IllegalArgumentException.class,
                              "A traffic light is in both signal group %s and signal group %s.", signalGroup1.getId(),
                              signalGroup2.getId());
                  }
              }
          }
          this.cycleTime = cycleTime;
          this.offset = offset;
          this.signalGroups = signalGroups;
          simulator.scheduleEventAbs(Time.ZERO, this, this, "setup", new Object[] { simulator, network });
      }
  
      /**
       * Initiates all traffic control events.
       * @param simulator OTSSimulatorInterface; simulator
      * @param network network
      * @throws SimRuntimeException when traffic light does not exist in the network
      */
     @SuppressWarnings("unused")
     private void setup(final OTSSimulatorInterface simulator, final Network network) throws SimRuntimeException
     {
         for (SignalGroup signalGroup : this.signalGroups)
         {
             signalGroup.startup(this.offset, this.cycleTime, simulator, network);
         }
     }
 
     /** {@inheritDoc} */
     @Override
     public void notify(final EventInterface event) throws RemoteException
     {
         // nothing
     }
 
     /** {@inheritDoc} */
     @Override
     public InvisibleObjectInterface clone(final OTSSimulatorInterface newSimulator, final Network newNetwork)
             throws NetworkException
     {
         Set<SignalGroup> signalGroupsCloned = new LinkedHashSet<>();
         for (SignalGroup signalGroup : this.signalGroups)
         {
             signalGroupsCloned.add(signalGroup.clone());
         }
         try
         {
             return new FixedTimeController(getId(), newSimulator, newNetwork, this.cycleTime, this.offset,
                     signalGroupsCloned);
         }
         catch (SimRuntimeException exception)
         {
             throw new RuntimeException("Cloning using a simulator that is not at time 0.");
         }
     }
 
     /** {@inheritDoc} */
     @Override
     public String getFullId()
     {
         return getId();
     }
 
     /** {@inheritDoc} */
     @Override
     public String toString()
     {
         return "FixedTimeController [cycleTime=" + this.cycleTime + ", offset=" + this.offset + ", signalGroups="
                 + this.signalGroups + ", full id=" + this.getFullId() + "]";
     }
 
     /**
      * <p>
      * Copyright (c) 2013-2019 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 21 feb. 2019 <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 static class SignalGroup implements Identifiable
     {
 
         /** Id. */
         private final String id;
 
         /** Traffic light ids. */
         private final ImmutableSet<String> trafficLightIds;
 
         /** Offset from start of cycle. */
         private final Duration offset;
 
         /** Pre-green duration. */
         private final Duration preGreen;
 
         /** Green duration. */
         private final Duration green;
 
         /** Yellow duration. */
         private final Duration yellow;
 
         // The following properties are remembered for the updates after the startup
 
         /** Traffic light objects. */
         private List<TrafficLight> trafficLights;
 
         /** Simulator. */
         private OTSSimulatorInterface simulator;
 
         /** Red time. */
         private Duration red;
 
         /**
          * Constructor without pre-green duration.
          * @param id String; id
          * @param trafficLightIds List&lt;String&gt;; traffic light ids
          * @param offset Duration; offset from start of cycle
          * @param green Duration; green duration
          * @param yellow Duration; yellow duration
          */
         public SignalGroup(final String id, final Set<String> trafficLightIds, final Duration offset, final Duration green,
                 final Duration yellow)
         {
             this(id, trafficLightIds, offset, Duration.ZERO, green, yellow);
         }
 
         /**
          * Constructor with pre-green duration.
          * @param id String; id
          * @param trafficLightIds List&lt;String&gt;; traffic light ids
          * @param offset Duration; offset from start of cycle
          * @param preGreen Duration; pre-green duration
          * @param green Duration; green duration
          * @param yellow Duration; yellow duration
          */
         public SignalGroup(final String id, final Set<String> trafficLightIds, final Duration offset,
                 final Duration preGreen, final Duration green, final Duration yellow)
         {
             Throw.whenNull(id, "Id may not be null.");
             Throw.whenNull(trafficLightIds, "Traffic light ids may not be null.");
             Throw.whenNull(offset, "Offset may not be null.");
             Throw.whenNull(preGreen, "Pre-green may not be null.");
             Throw.when(preGreen.lt(Duration.ZERO), IllegalArgumentException.class, "Pre green duration may not be negative");
             Throw.whenNull(green, "Green may not be null.");
             Throw.when(green.lt(Duration.ZERO), IllegalArgumentException.class, "Green duration may not be negative");
             Throw.whenNull(yellow, "Yellow may not be null.");
             Throw.when(yellow.lt(Duration.ZERO), IllegalArgumentException.class, "Yellow duration may not be negative");
             Throw.when(trafficLightIds.isEmpty(), IllegalArgumentException.class, "Traffic light ids may not be empty.");
             this.id = id;
             this.trafficLightIds = new ImmutableHashSet<>(trafficLightIds, Immutable.COPY);
             this.offset = offset;
             this.preGreen = preGreen;
             this.green = green;
             this.yellow = yellow;
         }
 
         /**
          * @return id.
          */
         @Override
         public String getId()
         {
             return this.id;
         }
 
         /**
          * @param controllerOffset
          * @param cycleTime
          * @param sim
          * @param network
          * @throws SimRuntimeException when traffic light does not exist in the network
          */
         public void startup(final Duration controllerOffset, final Duration cycleTime, final OTSSimulatorInterface sim,
                 final Network network) throws SimRuntimeException
         {
             this.simulator = sim;
             double totalOffsetSI = this.offset.si + controllerOffset.si;
             while (totalOffsetSI < 0.0)
             {
                 totalOffsetSI += cycleTime.si;
             }
             Duration totalOffset = Duration.createSI(totalOffsetSI % cycleTime.si);
             this.red = cycleTime.minus(this.preGreen).minus(this.green).minus(this.yellow);
             Throw.when(this.red.lt0(), IllegalArgumentException.class, "Cycle time shorter than sum of non-red times.");
 
             this.trafficLights = new ArrayList<>();
             ImmutableMap<String, TrafficLight> trafficLightObjects = network.getObjectMap(TrafficLight.class);
             for (String trafficLightId : this.trafficLightIds)
             {
                 TrafficLight trafficLight = trafficLightObjects.get(trafficLightId);
                 if (null == trafficLight) // Traffic light not found using id; try to find it by full id
                 {
                     trafficLight = trafficLightObjects.get(network.getId() + "." + trafficLightId);
                 }
                 Throw.when(trafficLight == null, SimRuntimeException.class, "Traffic light \"" + trafficLightId
                         + "\" in fixed time controller could not be found in network " + network.getId() + ".");
                 this.trafficLights.add(trafficLight);
             }
 
             Duration inCycleTime = Duration.createSI(totalOffset.si - cycleTime.si);
             while (inCycleTime.si < 0)
             {
                 inCycleTime = inCycleTime.plus(cycleTime);
             }
             Duration duration;
             if (inCycleTime.si < this.preGreen.si)
             {
                 setTrafficLights(TrafficLightColor.PREGREEN);
                 duration = this.preGreen.minus(inCycleTime);
             }
             else if (inCycleTime.si < this.preGreen.si + this.green.si)
             {
                 setTrafficLights(TrafficLightColor.GREEN);
                 duration = this.preGreen.plus(this.green).minus(inCycleTime);
             }
             else if (inCycleTime.si < this.preGreen.si + this.green.si + this.yellow.si)
             {
                 setTrafficLights(TrafficLightColor.YELLOW);
                 duration = this.preGreen.plus(this.green).plus(this.yellow).minus(inCycleTime);
             }
             else
             {
                 setTrafficLights(TrafficLightColor.RED);
                 duration = cycleTime.minus(inCycleTime);
             }
             this.simulator.scheduleEventRel(duration, this, this, "updateColors", null);
         }
 
         /**
          * Updates the color of the traffic lights.
          */
         @SuppressWarnings("unused")
         private void updateColors()
         {
             Duration duration = Duration.ZERO;
             TrafficLightColor color = this.trafficLights.get(0).getTrafficLightColor();
             while (duration.le0())
             {
                 switch (color)
                 {
                     case PREGREEN:
                         color = TrafficLightColor.GREEN;
                         duration = this.green;
                         break;
                     case GREEN:
                         color = TrafficLightColor.YELLOW;
                         duration = this.yellow;
                         break;
                     case YELLOW:
                         color = TrafficLightColor.RED;
                         duration = this.red;
                         break;
                     case RED:
                         color = TrafficLightColor.PREGREEN;
                         duration = this.preGreen;
                         break;
                     default:
                         throw new RuntimeException("Cannot happen.");
                 }
             }
             setTrafficLights(color);
             try
             {
                 this.simulator.scheduleEventRel(duration, this, this, "updateColors", null);
             }
             catch (SimRuntimeException exception)
             {
                 // cannot happen; we check all durations for consistency
                 throw new RuntimeException(exception);
             }
         }
 
         /**
          * Change the color of our traffic lights.
          * @param trafficLightColor the new traffic light color
          */
         private void setTrafficLights(final TrafficLightColor trafficLightColor)
         {
             for (TrafficLight trafficLight : this.trafficLights)
             {
                 trafficLight.setTrafficLightColor(trafficLightColor);
             }
         }
 
         /**
          * Clones the object for a cloned simulation.
          */
         @Override
         public SignalGroup clone()
         {
             return new SignalGroup(getId(), this.trafficLightIds.toSet(), this.offset, this.preGreen, this.green,
                     this.yellow);
         }
 
         /** {@inheritDoc} */
         @Override
         public int hashCode()
         {
             final int prime = 31;
             int result = 1;
             result = prime * result + ((this.id == null) ? 0 : this.id.hashCode());
             return result;
         }
 
         /** {@inheritDoc} */
         @Override
         public boolean equals(Object obj)
         {
             if (this == obj)
             {
                 return true;
             }
             if (obj == null)
             {
                 return false;
             }
             if (getClass() != obj.getClass())
             {
                 return false;
             }
             SignalGroup other = (SignalGroup) obj;
             if (this.id == null)
             {
                 if (other.id != null)
                 {
                     return false;
                 }
             }
             else if (!this.id.equals(other.id))
             {
                 return false;
             }
             return true;
         }
 
         /**
          * @return trafficLights.
          */
         public final ImmutableList<TrafficLight> getTrafficLights()
         {
             return new ImmutableArrayList<>(this.trafficLights);
         }
 
         /**
          * @return red.
          */
         public final Duration getRed()
         {
             return this.red;
         }
 
         /**
          * @return trafficLightIds.
          */
         public final ImmutableSet<String> getTrafficLightIds()
         {
             return this.trafficLightIds;
         }
 
         /**
          * @return offset.
          */
         public final Duration getOffset()
         {
             return this.offset;
         }
 
         /**
          * @return preGreen.
          */
         public final Duration getPreGreen()
         {
             return this.preGreen;
         }
 
         /**
          * @return green.
          */
         public final Duration getGreen()
         {
             return this.green;
         }
 
         /**
          * @return yellow.
          */
         public final Duration getYellow()
         {
             return this.yellow;
         }
 
         /** {@inheritDoc} */
         @Override
         public String toString()
         {
             return "SignalGroup [id=" + this.id + ", trafficLightIds=" + this.trafficLightIds + ", offset=" + this.offset
                     + ", preGreen=" + this.preGreen + ", green=" + this.green + ", yellow=" + this.yellow + "]";
         }
 
     }
 
     /**
      * @return cycleTime.
      */
     public final Duration getCycleTime()
     {
         return this.cycleTime;
     }
 
     /**
      * @return offset.
      */
     public final Duration getOffset()
     {
         return this.offset;
     }
 
     /**
      * @return signalGroups.
      */
     public final Set<SignalGroup> getSignalGroups()
     {
         return this.signalGroups;
     }
 
 }