package org.opentrafficsim.kpi.sampling;
   
   import java.util.ArrayList;
   import java.util.HashMap;
   import java.util.HashSet;
   import java.util.Iterator;
   import java.util.List;
   import java.util.Map;
   import java.util.Map.Entry;
  import java.util.Set;
  import java.util.UUID;
  
  import org.djunits.unit.LengthUnit;
  import org.djunits.value.vdouble.scalar.Duration;
  import org.djunits.value.vdouble.scalar.Frequency;
  import org.djunits.value.vdouble.scalar.Length;
  import org.djunits.value.vdouble.scalar.Time;
  import org.opentrafficsim.base.immutablecollections.ImmutableIterator;
  import org.opentrafficsim.kpi.interfaces.LaneDataInterface;
  import org.opentrafficsim.kpi.interfaces.LinkDataInterface;
  import org.opentrafficsim.kpi.sampling.meta.MetaDataSet;
  import org.opentrafficsim.kpi.sampling.meta.MetaDataType;
  
  import nl.tudelft.simulation.language.Throw;
  
  /**
   * A query defines which subset of trajectory information should be included. This is in terms of space-time regions, and in
   * terms of meta data of trajectories, e.g. only include trajectories of trucks.
   * <p>
   * Copyright (c) 2013-2016 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/current/license.html">OpenTrafficSim License</a>.
   * </p>
   * $LastChangedDate: 2015-07-24 02:58:59 +0200 (Fri, 24 Jul 2015) $, @version $Revision: 1147 $, by $Author: averbraeck $,
   * initial version Sep 21, 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 Query
  {
      /** unique id. */
      private final String id;
  
      /** Sampling. */
      private final Sampler sampling;
  
      /** Description. */
      private final String description;
  
      /** Meta data set. */
      private final MetaDataSet metaDataSet;
  
      /** Update frequency. */
      private final Frequency updateFrequency;
  
      /** Interval to gather statistics over. */
      private final Duration interval;
  
      /** List of space-time regions of this query. */
      private final List<SpaceTimeRegion> spaceTimeRegions = new ArrayList<>();
  
      /**
       * @param sampling sampling
       * @param id id
       * @param description description
       * @param metaDataSet meta data
       * @throws NullPointerException if sampling, description or metaDataSet is null
       */
      public Query(final Sampler sampling, final String id, final String description, final MetaDataSet metaDataSet)
      {
          this(sampling, description, metaDataSet, null, null);
      }
  
      /**
       * @param sampling sampling
       * @param id id
       * @param description description
       * @param metaDataSet meta data
       * @param interval interval to gather statistics over
       * @throws NullPointerException if sampling, description or metaDataSet is null
       */
      public Query(final Sampler sampling, final String id, final String description, final MetaDataSet metaDataSet, final Duration interval)
      {
          this(sampling, description, metaDataSet, null, interval);
      }
  
      /**
       * @param sampling sampling
       * @param id id
       * @param description description
       * @param metaDataSet meta data
       * @param updateFrequency update frequency
       * @throws NullPointerException if sampling, description or metaDataSet is null
       */
      public Query(final Sampler sampling, final String id, final String description, final MetaDataSet metaDataSet,
              final Frequency updateFrequency)
      {
          this(sampling, description, metaDataSet, updateFrequency, null);
      }
 
     /**
      * @param sampling sampling
      * @param id id
      * @param description description
      * @param metaDataSet meta data
      * @param updateFrequency update frequency
      * @param interval interval to gather statistics over
      * @throws NullPointerException if sampling, description or metaDataSet is null
      */
     public Query(final Sampler sampling, final String id, final String description, final MetaDataSet metaDataSet,
             final Frequency updateFrequency, final Duration interval)
     {
         Throw.whenNull(sampling, "Sampling may not be null.");
         Throw.whenNull(description, "Description may not be null.");
         Throw.whenNull(metaDataSet, "Meta data may not be null.");
         this.sampling = sampling;
         this.metaDataSet = new MetaDataSet(metaDataSet);
         this.id = id == null ? UUID.randomUUID().toString() : id;
         this.description = description;
         this.updateFrequency = updateFrequency;
         this.interval = interval;
         sampling.registerMetaDataTypes(metaDataSet.getMetaDataTypes());
     }
     
     /**
      * @param sampling sampling
      * @param description description
      * @param metaDataSet meta data
      * @throws NullPointerException if sampling, description or metaDataSet is null
      */
     public Query(final Sampler sampling, final String description, final MetaDataSet metaDataSet)
     {
         this(sampling, null, description, metaDataSet, null, null);
     }
 
     /**
      * @param sampling sampling
      * @param description description
      * @param metaDataSet meta data
      * @param interval interval to gather statistics over
      * @throws NullPointerException if sampling, description or metaDataSet is null
      */
     public Query(final Sampler sampling, final String description, final MetaDataSet metaDataSet, final Duration interval)
     {
         this(sampling, null, description, metaDataSet, null, interval);
     }
 
     /**
      * @param sampling sampling
      * @param description description
      * @param metaDataSet meta data
      * @param updateFrequency update frequency
      * @throws NullPointerException if sampling, description or metaDataSet is null
      */
     public Query(final Sampler sampling, final String description, final MetaDataSet metaDataSet,
             final Frequency updateFrequency)
     {
         this(sampling, null, description, metaDataSet, updateFrequency, null);
     }
 
     /**
      * @param sampling sampling
      * @param description description
      * @param metaDataSet meta data
      * @param updateFrequency update frequency
      * @param interval interval to gather statistics over
      * @throws NullPointerException if sampling, description or metaDataSet is null
      */
     public Query(final Sampler sampling, final String description, final MetaDataSet metaDataSet,
             final Frequency updateFrequency, final Duration interval)
     {
         this(sampling, null, description, metaDataSet, updateFrequency, interval);
     }
 
     /**
      * return the unique id for the query.
      * @return String; the unique id for the query
      */
     public String getId()
     {
         return this.id.toString();
     }
 
     /**
      * @return description
      */
     public String getDescription()
     {
         return this.description;
     }
 
     /**
      * @return updateFrequency.
      */
     public Frequency getUpdateFrequency()
     {
         return this.updateFrequency;
     }
 
     /**
      * @return interval.
      */
     public Duration getInterval()
     {
         return this.interval;
     }
 
     /**
      * @return number of meta data entries
      */
     public int metaDataSize()
     {
         return this.metaDataSet.size();
     }
 
     /**
      * @return iterator over meta data entries, removal is not allowed
      */
     public Iterator<Entry<MetaDataType<?>, Set<?>>> getMetaDataSetIterator()
     {
         return this.metaDataSet.getMetaDataSetIterator();
     }
 
     /**
      * Defines a region in space and time for which this query is valid. All lanes in the link are included.
      * @param link link
      * @param direction direction
      * @param startPosition start position
      * @param endPosition end position
      * @param startTime start time
      * @param endTime end time
      */
     public void addSpaceTimeRegionLink(final LinkDataInterface link, final KpiGtuDirectionality direction,
             final Length startPosition, final Length endPosition, final Time startTime, final Time endTime)
     {
         Throw.whenNull(link, "Link may not be null.");
         Throw.whenNull(direction, "Direction may not be null.");
         Throw.whenNull(startPosition, "Start position may not be null.");
         Throw.whenNull(endPosition, "End position may not be null.");
         Throw.whenNull(startTime, "Start time may not be null.");
         Throw.whenNull(endTime, "End time may not be null.");
         Throw.when(endPosition.lt(startPosition), IllegalArgumentException.class,
                 "End position should be greater than start position.");
         Throw.when(endTime.lt(startTime), IllegalArgumentException.class, "End time should be greater than start time.");
         for (LaneDataInterface lane : link.getLaneDatas())
         {
             Length x0 = new Length(lane.getLength().si * startPosition.si / link.getLength().si, LengthUnit.SI);
             Length x1 = new Length(lane.getLength().si * endPosition.si / link.getLength().si, LengthUnit.SI);
             addSpaceTimeRegion(new KpiLaneDirection(lane, direction), x0, x1, startTime, endTime);
         }
     }
 
     /**
      * Defines a region in space and time for which this query is valid.
      * @param laneDirection lane direction
      * @param startPosition start position
      * @param endPosition end position
      * @param startTime start time
      * @param endTime end time
      */
     public void addSpaceTimeRegion(final KpiLaneDirection laneDirection, final Length startPosition, final Length endPosition,
             final Time startTime, final Time endTime)
     {
         Throw.whenNull(laneDirection, "Lane direction may not be null.");
         Throw.whenNull(startPosition, "Start position may not be null.");
         Throw.whenNull(endPosition, "End position may not be null.");
         Throw.whenNull(startTime, "Start time may not be null.");
         Throw.whenNull(endTime, "End time may not be null.");
         Throw.when(endPosition.lt(startPosition), IllegalArgumentException.class,
                 "End position should be greater than start position.");
         Throw.when(endTime.lt(startTime), IllegalArgumentException.class, "End time should be greater than start time.");
         SpaceTimeRegion spaceTimeRegion = new SpaceTimeRegion(laneDirection, startPosition, endPosition, startTime, endTime);
         this.sampling.registerSpaceTimeRegion(spaceTimeRegion);
         this.spaceTimeRegions.add(spaceTimeRegion);
     }
 
     /**
      * @return number of space-time regions
      */
     public int spaceTimeRegionSize()
     {
         return this.spaceTimeRegions.size();
     }
 
     /**
      * @return iterator over space-time regions, removal is not allowed
      */
     public Iterator<SpaceTimeRegion> getSpaceTimeIterator()
     {
          return new ImmutableIterator<>(this.spaceTimeRegions.iterator());
     }
 
     /**
      * Returns a list of TrajectoryGroups in accordance with the query. Each {@code TrajectoryGroup} contains {@code Trajectory}
      * objects pertaining to a {@code SpaceTimeRegion} from the query. A {@code Trajectory} is only included if all the meta
      * data of this query accepts the trajectory.
      * @param startTime start time of interval to get trajectory groups for
      * @param endTime start time of interval to get trajectory groups for
      * @param <T> underlying class of meta data type and its value
      * @return list of trajectory groups in accordance with the query
      */
     @SuppressWarnings("unchecked")
     public <T> List<TrajectoryGroup> getTrajectoryGroups(final Time startTime, final Time endTime)
     {
         Throw.whenNull(startTime, "Start t may not be null.");
         Throw.whenNull(endTime, "End t may not be null.");
         // Step 1) gather trajectories per GTU, truncated over space and time
         Map<String, TrajectoryAcceptList> trajectoryAcceptLists = new HashMap<>();
         List<TrajectoryGroup> trajectoryGroupList = new ArrayList<>();
         for (SpaceTimeRegion spaceTimeRegion : this.spaceTimeRegions)
         {
             Time start = startTime.gt(spaceTimeRegion.getStartTime()) ? startTime : spaceTimeRegion.getStartTime();
             Time end = endTime.lt(spaceTimeRegion.getEndTime()) ? endTime : spaceTimeRegion.getEndTime();
             TrajectoryGroup trajectoryGroup;
             if (this.sampling.getTrajectoryGroup(spaceTimeRegion.getLaneDirection()) == null)
             {
                 trajectoryGroup = new TrajectoryGroup(start, spaceTimeRegion.getLaneDirection());
             }
             else
             {
                 trajectoryGroup = this.sampling.getTrajectoryGroup(spaceTimeRegion.getLaneDirection())
                         .getTrajectoryGroup(spaceTimeRegion.getStartPosition(), spaceTimeRegion.getEndPosition(), start, end);
             }
             for (Trajectory trajectory : trajectoryGroup.getTrajectories())
             {
                 if (!trajectoryAcceptLists.containsKey(trajectory.getGtuId()))
                 {
                     trajectoryAcceptLists.put(trajectory.getGtuId(), new TrajectoryAcceptList());
                 }
                 trajectoryAcceptLists.get(trajectory.getGtuId()).addTrajectory(trajectory, trajectoryGroup);
             }
             trajectoryGroupList.add(trajectoryGroup);
         }
         // Step 2) accept per GTU
         Iterator<String> iterator = trajectoryAcceptLists.keySet().iterator();
         while (iterator.hasNext())
         {
             String gtuId = iterator.next();
             TrajectoryAcceptList trajectoryAcceptListCombined = trajectoryAcceptLists.get(gtuId);
             trajectoryAcceptListCombined.acceptAll(); // refuse only if any meta data type refuses
             for (MetaDataType<?> metaDataType : this.metaDataSet.getMetaDataTypes())
             {
                 // create safe copy per meta data type, with defaults accepts = false
                 TrajectoryAcceptList trajectoryAcceptList = trajectoryAcceptLists.get(gtuId);
                 TrajectoryAcceptList trajectoryAcceptListCopy = new TrajectoryAcceptList();
                 for (int i = 0; i < trajectoryAcceptList.size(); i++)
                 {
                     trajectoryAcceptListCopy.addTrajectory(trajectoryAcceptList.getTrajectory(i),
                             trajectoryAcceptList.getTrajectoryGroup(i));
                 }
                 // request meta data type to accept or reject
                 ((MetaDataType<T>) metaDataType).accept(trajectoryAcceptListCopy,
                         (Set<T>) new HashSet<>(this.metaDataSet.get(metaDataType)));
                 // combine acceptance/rejection of meta data type so far
                 for (int i = 0; i < trajectoryAcceptListCopy.size(); i++)
                 {
                     Trajectory trajectory = trajectoryAcceptListCopy.getTrajectory(i);
                     trajectoryAcceptListCombined.acceptTrajectory(trajectory,
                             trajectoryAcceptListCombined.isAccepted(trajectory)
                                     && trajectoryAcceptListCopy.isAccepted(trajectory));
                 }
             }
         }
         // Step 3) filter trajectories
         List<TrajectoryGroup> out = new ArrayList<>();
         for (TrajectoryGroup full : trajectoryGroupList)
         {
             TrajectoryGroup filtered = new TrajectoryGroup(full.getStartTime(), full.getLaneDirection());
             for (Trajectory trajectory : full.getTrajectories())
             {
                 String gtuId = trajectory.getGtuId();
                 if (trajectoryAcceptLists.get(gtuId).isAccepted(trajectory))
                 {
                     filtered.addTrajectory(trajectory);
                 }
             }
             out.add(filtered);
         }
         return out;
     }
 
     /** {@inheritDoc} */
     @Override
     public int hashCode()
     {
         final int prime = 31;
         int result = 1;
         result = prime * result + ((this.description == null) ? 0 : this.description.hashCode());
         result = prime * result + ((this.interval == null) ? 0 : this.interval.hashCode());
         result = prime * result + ((this.metaDataSet == null) ? 0 : this.metaDataSet.hashCode());
         result = prime * result + ((this.sampling == null) ? 0 : this.sampling.hashCode());
         result = prime * result + ((this.spaceTimeRegions == null) ? 0 : this.spaceTimeRegions.hashCode());
         result = prime * result + ((this.id == null) ? 0 : this.id.hashCode());
         result = prime * result + ((this.updateFrequency == null) ? 0 : this.updateFrequency.hashCode());
         return result;
     }
 
     /** {@inheritDoc} */
     @Override
     public boolean equals(final Object obj)
     {
         if (this == obj)
         {
             return true;
         }
         if (obj == null)
         {
             return false;
         }
         if (getClass() != obj.getClass())
         {
             return false;
         }
         Query other = (Query) obj;
         if (this.description == null)
         {
             if (other.description != null)
             {
                 return false;
             }
         }
         else if (!this.description.equals(other.description))
         {
             return false;
         }
         if (this.interval == null)
         {
             if (other.interval != null)
             {
                 return false;
             }
         }
         else if (!this.interval.equals(other.interval))
         {
             return false;
         }
         if (this.metaDataSet == null)
         {
             if (other.metaDataSet != null)
             {
                 return false;
             }
         }
         else if (!this.metaDataSet.equals(other.metaDataSet))
         {
             return false;
         }
         if (this.sampling == null)
         {
             if (other.sampling != null)
             {
                 return false;
             }
         }
         else if (!this.sampling.equals(other.sampling))
         {
             return false;
         }
         if (this.spaceTimeRegions == null)
         {
             if (other.spaceTimeRegions != null)
             {
                 return false;
             }
         }
         else if (!this.spaceTimeRegions.equals(other.spaceTimeRegions))
         {
             return false;
         }
         if (this.id == null)
         {
             if (other.id != null)
             {
                 return false;
             }
         }
         else if (!this.id.equals(other.id))
         {
             return false;
         }
         if (this.updateFrequency == null)
         {
             if (other.updateFrequency != null)
             {
                 return false;
             }
         }
         else if (!this.updateFrequency.equals(other.updateFrequency))
         {
             return false;
         }
         return true;
     }
 
     /** {@inheritDoc} */
     @Override
     public String toString()
     {
         return "Query (" + this.description + ")";
     }
 
 }