package org.lcsim.recon.tracking.trflayer;
   import java.util.Map;
   import java.util.HashMap;
   import java.util.TreeMap;
   import java.util.Collection;
   import java.util.Iterator;
   import java.util.List;
   import java.util.ArrayList;
   
  import org.lcsim.recon.tracking.trfutil.RandomSimulator;
  
  import org.lcsim.recon.tracking.trfbase.VTrack;
  
  /**
   * A detector simulator contains a detector and a list of layer
   * simulators which match the layers in the detector.
   *<p>
   * The base simulator is constructed from the detector reference.
   * Subclasses add layer simulators either directly or by extraction from
   * other detector simulators.
   *<p>
   * Methods to add or drop clusters invoke the corresponding method on
   * each of the layer simulators.
   *<p>
   * Although this class is not abstract, the constructor is hidden and
   * users must provide subclasses to instantiate.  The expectation is that
   * users will add layers or detectors in the subclass constructor.
   *
   *@author Norman A. Graf
   *@version 1.0
   *
   **/
  
  public class DetectorSimulator extends RandomSimulator
  {
      
      // attributes
      
      // Detector.
      private Detector _det;
      
      // Layer simulators.
      private Map _lsims;
      
      // methods
      
      // Constructors from a detector.
      protected DetectorSimulator( Detector det)
      {
          //_lsims = new HashMap();
          _lsims = new TreeMap(); // for ordering of layers
          _det = det;
      }
      
      // Add a layer simulator by name.
      // Name must be known to the detector.
      // Detector and layer simulator must reference the same layer
      // object.
      // Return nonzero for error.
      protected DetSimReturnStatus
              addLayerSimulator(String name, LayerSimulator lsim)
      {
          // Check the name.
          if ( ! _det.isAssigned(name) ) return DetSimReturnStatus.UNKNOWN_NAME;
          
          // Fetch the layers and check for match.
          Layer detlyr = _det.layer(name);
          if(detlyr instanceof InteractingLayer) detlyr = ((InteractingLayer)detlyr).layer();
          Layer simlyr = lsim.layer();
          
          if ( !detlyr.equals(simlyr) ) return DetSimReturnStatus.LAYER_MISMATCH;
          
          _lsims.put(name, lsim);
          
          return DetSimReturnStatus.OK;
          
      }
      
      // Add all the layer simulators from a detector simulator.
      // Each name must be known to the local detector.
      // Detector and each layer simulator must reference the same
      // layer object.
      // Return nonzero for error.
      protected DetSimReturnStatus
              addDetectorSimulator(  DetectorSimulator dsim)
      {
          // Loop over layer simulators.
          for(Iterator i=dsim._lsims.entrySet().iterator(); i.hasNext(); )
          {
              Map.Entry e = (Map.Entry) i.next();
              String name = (String) e.getKey();
              LayerSimulator lsim = (LayerSimulator) e.getValue();
              DetSimReturnStatus stat = addLayerSimulator(name,lsim);
              if ( stat != DetSimReturnStatus.OK ) return stat;
          }
          
          return DetSimReturnStatus.OK;
          
      }
     
     // methods
     
     //
     
     /**
      *Return the detector.
      *
      * @return Detector
      */
     public Detector detector()
     {
         return _det;
     }
     
     //
     
     /**
      *Return the list of generators.
      *
      * @return list of HitGenerators
      */
     public List generators()
     {
         List gens = new ArrayList();
         // Loop over layer simulators.
         for(Iterator i=_lsims.entrySet().iterator(); i.hasNext(); )
         {
             Map.Entry e = (Map.Entry) i.next();
             
             LayerSimulator lsim = (LayerSimulator) e.getValue();
             List newgens = lsim.generators();
             for ( Iterator igen=newgens.iterator(); igen.hasNext(); )
             {
                 gens.add(igen.next());
             }
         }
         return gens;
     }
     
     //
     
     /**
      *Use the specified track to add clusters with each layer simulator.
      *
      * @param   trv VTrack for which to generate clusters
      */
     public void addClusters( VTrack trv )
     {
         addClusters(trv, 0);
     }
     
     
     /**
      *Use the specified track to add clusters with each layer simulator.
      *
      * @param   trv VTrack for which to generate clusters
      * @param   mcid MC track ID to associate with this track
      */
     public void addClusters( VTrack trv, int mcid )
     {
         
         // Loop over layer simulators.
         for (Iterator i=_lsims.entrySet().iterator(); i.hasNext(); )
         {
             Map.Entry e = (Map.Entry) i.next();
             LayerSimulator lsim = (LayerSimulator) e.getValue();
             lsim.addClusters(trv, mcid);
         }
         
     }
     
     //
     
     /**
      *Drop clusters from each layer simulator.
      *
      */
     public void dropClusters()
     {
         // Loop over layer simulators.
         for (Iterator i=_lsims.entrySet().iterator(); i.hasNext(); )
         {
             Map.Entry e = (Map.Entry) i.next();
             LayerSimulator lsim = (LayerSimulator) e.getValue();
             lsim.dropClusters();
         }
         
     }
     
     //
     
     /**
      *write out the generators
      *
      */
     public void printGenerators()
     {
         
     }
     
     
     /**
      *output stream
      *
      * @return String representation of this class
      */
     public String toString()
     {
         int size = _lsims.size();
         StringBuffer sb = new StringBuffer(getClass().getName()+" with " + size + " layer generator");
         if ( size != 1 ) sb.append("s");
         if ( size == 0 )
         {
             sb.append(".");
         }
         else
         {
             sb.append(":\n");
             if ( _lsims.size() == 0 )
             {
                 sb.append("There are no generators.");
                 return sb.toString();
             }
             for (Iterator i=_lsims.entrySet().iterator(); i.hasNext(); )
             {
                 Map.Entry e = (Map.Entry) i.next();
                 
                 sb.append( "\n" + e.getKey()+": "+e.getValue() + "\n");
             }
         }
         return sb.toString();
     }
 }