// -------------------------------------------------------------------------
// -----                       CbmStack header file                    -----
// -----           Created 10/08/04  by D. Bertini / V. Friese         -----
// -------------------------------------------------------------------------


/** CbmStack.h
 *@author D.Bertini <d.bertini@gsi.de>
 *@author V.Friese <v.friese@gsi.de>
 **
 ** This class handles the particle stack for the transport simulation.
 ** For the stack FILO functunality, it uses the STL stack. To store
 ** the tracks, a TParticle arry is used. At the end of the event,
 ** it is filtered and copied to a CbmMCTrack array, which is written to
 ** the output. 
 **/


#ifndef CBMSTACK_H
#define CBMSTACK_H


#include <map>
#include <stack>
#include <iostream>
#include "TClonesArray.h"
#include "TVirtualMCStack.h"
#include "CbmGenericStack.h"

using std::map;
using std::stack;


class CbmStack : public CbmGenericStack
{

 public:

  /** Default constructor  **/
  CbmStack();


  /** Destructor with estimated array size  **/
  CbmStack(Int_t size);


  /** Destructor  **/
  virtual ~CbmStack();

  /** Virtual method PushTrack.
   ** Add a TParticle to the stack.
   *@param toBeDone  Flag for tracking
   *@param parentID  Index of mother particle
   *@param pdgCode   Particle type (PDG encoding)
   *@param px,py,pz  Momentum components at start vertex [GeV]
   *@param e         Total energy at start vertex [GeV]
   *@param vx,vy,vz  Coordinates of start vertex [cm]
   *@param time      Start time of track [s]
   *@param polx,poly,polz Polarisation vector
   *@param proc      Production mechanism (VMC encoding)
   *@param ntr       Track number (filled by the stack)
   *@param weight    Particle weight
   *@param is        Generation status code (whatever that means)
   **/
  virtual void PushTrack(Int_t toBeDone, Int_t parentID, Int_t pdgCode,
			 Double_t px, Double_t py, Double_t pz,
			 Double_t e, Double_t vx, Double_t vy, 
			 Double_t vz, Double_t time, Double_t polx, 
			 Double_t poly, Double_t polz, TMCProcess proc, 
			 Int_t& ntr, Double_t weight, Int_t is);


  /** Virtual method PopNextTrack.
   ** Gets next particle for tracking from the stack.
   *@param  iTrack  index of popped track
   *@return Pointer to the TParticle of the track
   **/
  virtual TParticle* PopNextTrack(Int_t& iTrack);


  /** Virtual method PopPrimaryForTracking.
   ** Gets primary particle by index for tracking from stack.
   *@param  iPrim   index of primary particle
   *@return Pointer to the TParticle of the track
   **/
  virtual TParticle* PopPrimaryForTracking(Int_t iPrim); 


  /** Add a TParticle to the fParticles array **/
  virtual void AddParticle(TParticle* part);


  /** Fill the MCTrack output array, applying filter criteria **/
  virtual void FillTrackArray();


  /** Update the track index in the MCTracks and MCPoints **/
  virtual void UpdateTrackIndex(TRefArray* detArray);


  /** Resets arrays and stack and deletes particles and tracks **/
  virtual void Reset();


  /** Register the MCTrack array to the Root Manager  **/
  virtual void Register();


  /** Output to screen 
   **@param iVerbose: 0=events summary, 1=track info
   **/
  virtual void Print(Int_t iVerbose=0) const;


  /** Modifiers  **/
  virtual void SetCurrentTrack(Int_t iTrack);
  void StoreSecondaries(Bool_t choice = kTRUE) { fStoreSecondaries = choice; }
  void SetMinPoints(Int_t min)                 { fMinPoints        = min;    }
  void SetEnergyCut(Double_t eMin)             { fEnergyCut        = eMin;   }
  void StoreMothers(Bool_t choice = kTRUE)     { fStoreMothers     = choice; }


  /** Accessors **/
  virtual Int_t GetNtrack() const;   // Total number of tracks
  virtual Int_t GetNprimary() const; // Number of primaries
  virtual TParticle* GetCurrentTrack() const;
  virtual Int_t GetCurrentTrackNumber() const; 
  virtual Int_t GetCurrentParentTrackNumber() const;
  TParticle* GetParticle(Int_t trackID) const;
  TClonesArray* GetListOfParticles() { return fParticles; }

 private:

    
  /** STL stack (FILO) used to handle the TParticles for tracking **/
  stack<TParticle*>  fStack;           //!


  /** Array of TParticles (contains all TParticles put into or created
   ** by the transport 
   **/
  TClonesArray* fParticles;            //!


  /** Array of CbmMCTracks containg the tracks written to the output **/
  TClonesArray* fTracks;


  /** STL map from particle index to storage flag  **/
  map<Int_t, Bool_t>           fStoreMap;        //!
  map<Int_t, Bool_t>::iterator fStoreIter;       //!


  /** STL map from particle index to track index  **/
  map<Int_t, Int_t>            fIndexMap;        //!
  map<Int_t, Int_t>::iterator  fIndexIter;       //!

  
  /** Some indizes and counters **/
  Int_t fCurrentTrack;  //! Index of current track
  Int_t fNPrimaries;    //! Number of primary particles
  Int_t fNParticles;    //! Number of entries in fParticles
  Int_t fNTracks;       //! Number of entries in fTracks
  Int_t fIndex;         //! Used for merging

  /** Variables defining the criteria for output selection **/
  Bool_t     fStoreSecondaries;
  Int_t      fMinPoints;
  Double32_t fEnergyCut;
  Bool_t     fStoreMothers;


  /** Mark tracks for output using selection criteria  **/
  void SelectTracks();


  ClassDef(CbmStack,1)

      
};






#endif