/**************************************************************************
 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
 *                                                                        *
 * Author: The ALICE Off-line Project.                                    *
 * Contributors are mentioned in the code where appropriate.              *
 *                                                                        *
 * Permission to use, copy, modify and distribute this software and its   *
 * documentation strictly for non-commercial purposes is hereby granted   *
 * without fee, provided that the above copyright notice appears in all   *
 * copies and that both the copyright notice and this permission notice   *
 * appear in the supporting documentation. The authors make no claims     *
 * about the suitability of this software for any purpose. It is          *
 * provided "as is" without express or implied warranty.                  *
 **************************************************************************/

/*
$Log$
Revision 1.9.2.15  2000/10/04 16:56:40  nilsen
Needed to include stdlib.h

=======
Revision 1.22  2000/10/04 19:45:52  barbera
Corrected by F. Carminati for v3.04

Revision 1.21  2000/10/02 21:28:08  fca
Removal of useless dependecies via forward declarations

Revision 1.20  2000/10/02 16:31:39  barbera
General code clean-up

Revision 1.9.2.14  2000/10/02 15:43:51  barbera
General code clean-up (e.g., printf -> cout)

Revision 1.19  2000/09/22 12:13:25  nilsen
Patches and updates for fixes to this and other routines.

Revision 1.18  2000/07/12 05:32:20  fca
Correcting several syntax problem with static members

Revision 1.17  2000/07/10 16:07:18  fca
Release version of ITS code

Revision 1.9.2.3  2000/02/02 13:42:09  barbera
fixed AliITS.cxx for new AliRun structure. Added ITS hits list to list of hits which will have their track numbers updated

Revision 1.9.2.2  2000/01/23 03:03:13  nilsen
//fixed FillModule. Removed fi(fabs(xl)<dx....

Revision 1.9.2.1  2000/01/12 19:03:32  nilsen
This is the version of the files after the merging done in December 1999.
See the ReadMe110100.txt file for details

Revision 1.9  1999/11/14 14:33:25  fca
Correct problems with distructors and pointers, thanks to I.Hrivnacova

Revision 1.8  1999/09/29 09:24:19  fca
Introduction of the Copyright and cvs Log

*/

///////////////////////////////////////////////////////////////////////////////
//
//      An overview of the basic philosophy of the ITS code development
// and analysis is show in the figure below.
//Begin_Html
/*
<img src="picts/ITS/ITS_Analysis_schema.gif">
</pre>
<br clear=left>
<font size=+2 color=red>
<p>Roberto Barbera is in charge of the ITS Offline code (1999).
<a href="mailto:roberto.barbera@ct.infn.it">Roberto Barbera</a>.
</font>
<pre>
*/
//End_Html
//
//  AliITS. Inner Traking System base class.
//  This class contains the base procedures for the Inner Tracking System
//
//Begin_Html
/*
<img src="picts/ITS/AliITS_Class_Diagram.gif">
</pre>
<br clear=left>
<font size=+2 color=red>
<p>This show the class diagram of the different elements that are part of
the AliITS class.
</font>
<pre>
*/
//End_Html
//
// Version: 0
// Written by Rene Brun, Federico Carminati, and Roberto Barbera
//
// Version: 1
// Modified and documented by Bjorn S. Nilsen
// July 11 1999
//
// Version: 2
// Modified and documented by A. Bologna
// October 18 1999
//
// AliITS is the general base class for the ITS. Also see AliDetector for
// futher information.
//
///////////////////////////////////////////////////////////////////////////////
#include <stdlib.h>
#include <TMath.h>
#include <TRandom.h>
#include <TBranch.h>
#include <TVector.h>
#include <TObjArray.h>
#include <TROOT.h>
#include <TObjectTable.h>
#include <TFile.h>
#include <TTree.h>
#include <TString.h>



#include "AliRun.h"
#include "AliITS.h"
#include "AliITSMap.h"
#include "AliITSDetType.h"
#include "AliITSClusterFinder.h"
#include "AliITSsimulation.h"
#include "AliITSresponse.h"
#include "AliITSsegmentationSPD.h"
#include "AliITSresponseSPD.h"
#include "AliITSsegmentationSDD.h"
#include "AliITSresponseSDD.h"
#include "AliITSsegmentationSSD.h"
#include "AliITSresponseSSD.h"
#include "AliITShit.h"
#include "AliITSgeom.h"
#include "AliITSdigit.h"
#include "AliITSmodule.h"
#include "AliITSRecPoint.h"
#include "AliITSRawCluster.h"
#include "AliMC.h"
#include "stdlib.h"

const Int_t AliITS::fgkNTYPES=3;

ClassImp(AliITS)
 
//_____________________________________________________________________________
AliITS::AliITS() : AliDetector() {
  //
  // Default initialiser for ITS
  //     The default constructor of the AliITS class. In addition to
  // creating the AliITS class it zeros the variables fIshunt (a member
  // of AliDetector class), fEuclidOut, and fIdN, and zeros the pointers
  // fITSpoints, fIdSens, and fIdName. The AliDetector default constructor
  // is also called.
  //


  fIshunt     = 0;
  fEuclidOut  = 0;

  //fNDetTypes = fgkNTYPES;
  fIdN        = 0;
  fIdName     = 0;
  fIdSens     = 0;
  fITSmodules = 0;
  //
  fDetTypes   = 0;
  //
  fDtype  = 0;
  fNdtype = 0;
  fCtype  = 0;
  fNctype = 0;
  fRecPoints = 0;
  fNRecPoints = 0;
  fTreeC = 0;
  //
  fITSgeom=0;
}

//_____________________________________________________________________________
AliITS::AliITS(const char *name, const char *title):AliDetector(name,title){
  //
  // Default initialiser for ITS
  //     The constructor of the AliITS class. In addition to creating the
  // AliITS class, it allocates memory for the TClonesArrays fHits and
  // fDigits, and for the TObjArray fITSpoints. It also zeros the variables
  // fIshunt (a member of AliDetector class), fEuclidOut, and fIdN, and zeros
  // the pointers fIdSens and fIdName. To help in displaying hits via the ROOT
  // macro display.C AliITS also sets the marker color to red. The variables
  // passes with this constructor, const char *name and *title, are used by
  // the constructor of AliDetector class. See AliDetector class for a
  // description of these parameters and its constructor functions.
  //


  fHits       = new TClonesArray("AliITShit", 1560);
  gAlice->AddHitList(fHits);

  //fNDetTypes = fgkNTYPES;

  fNdtype = new Int_t[fgkNTYPES];
  fDtype = new TObjArray(fgkNTYPES);

  fNctype = new Int_t[fgkNTYPES];
  fCtype = new TObjArray(fgkNTYPES);


  fRecPoints = 0;
  fNRecPoints = 0;

  fTreeC = 0;

  fITSmodules = 0; 

  fIshunt     = 0;
  fEuclidOut  = 0;
  fIdN        = 0;
  fIdName     = 0;
  fIdSens     = 0;
 
  fDetTypes = new TObjArray(fgkNTYPES);  

  Int_t i;
  for(i=0;i<fgkNTYPES;i++) {
    (*fDetTypes)[i]=new AliITSDetType(); 
    fNdtype[i]=0;
    fNctype[i]=0;
   }
  //

  SetMarkerColor(kRed);

  fITSgeom=0;
}
//___________________________________________________________________________
AliITS::AliITS(AliITS &source){
  // copy constructor
  if(this==&source) return;
  Error("AliITS::Copy constructor",
  	"You are not allowed to make a copy of the AliITS");
  exit(1);
}
//____________________________________________________________________________
AliITS& AliITS::operator=(AliITS &source){
  // assignment operator
  if(this==&source) return *this;
  Error("AliITS::operator=",
  	"You are not allowed to make a copy of the AliITS");
  exit(1);
  return *this; //fake return
}
//____________________________________________________________________________
void AliITS::ClearModules(){
  //clear the modules TObjArray

  if(fITSmodules) fITSmodules->Delete();

}
//_____________________________________________________________________________
AliITS::~AliITS(){
  //
  // Default distructor for ITS
  //     The default destructor of the AliITS class. In addition to deleting
  // the AliITS class it deletes the memory pointed to by the fHits, fDigits,
  // fIdSens, fIdName, and fITSpoints.
  //


  delete fHits;
  delete fDigits;
  delete fRecPoints;
//  delete fIdName;        // TObjArray of TObjStrings
  if(fIdName!=0) delete[] fIdName;  // Array of TStrings
  if(fIdSens!=0) delete[] fIdSens;
  if(fITSmodules!=0) {
      this->ClearModules();
      delete fITSmodules;
  }// end if fITSmodules!=0

  //
  if(fDtype) {
    fDtype->Delete();
    delete fDtype;
  }
  delete [] fNdtype;
  if (fCtype) {
    fCtype->Delete();
    delete fCtype;
  }
  delete [] fNctype;
  //

  if (fDetTypes) {
    fDetTypes->Delete();
    delete fDetTypes;
  }

  if (fTreeC) delete fTreeC;

  if (fITSgeom) delete fITSgeom;

}

//___________________________________________
AliITSDetType* AliITS::DetType(Int_t id)
{
  //return pointer to id detector type
    return ((AliITSDetType*) (*fDetTypes)[id]);

}
//___________________________________________
void AliITS::SetClasses(Int_t id, const char *digit, const char *cluster)
{
  //set the digit and cluster classes to be used for the id detector type
    ((AliITSDetType*) (*fDetTypes)[id])->ClassNames(digit,cluster);

}
//___________________________________________
void AliITS::SetResponseModel(Int_t id, AliITSresponse *response)
{
  //set the response model for the id detector type

    ((AliITSDetType*) (*fDetTypes)[id])->ResponseModel(response);

}

//___________________________________________
void AliITS::SetSegmentationModel(Int_t id, AliITSsegmentation *seg)
{
  //set the segmentation model for the id detector type

    ((AliITSDetType*) (*fDetTypes)[id])->SegmentationModel(seg);

}

//___________________________________________
void AliITS::SetSimulationModel(Int_t id, AliITSsimulation *sim)
{
  //set the simulation model for the id detector type

   ((AliITSDetType*) (*fDetTypes)[id])->SimulationModel(sim);

}
//___________________________________________
void AliITS::SetReconstructionModel(Int_t id, AliITSClusterFinder *reconst)
{
  //set the cluster finder model for the id detector type

   ((AliITSDetType*) (*fDetTypes)[id])->ReconstructionModel(reconst);

}

//_____________________________________________________________________________
void AliITS::AddHit(Int_t track, Int_t *vol, Float_t *hits){
  //
  // Add an ITS hit
  //     The function to add information to the AliITShit class. See the
  // AliITShit class for a full description. This function allocates the
  // necessary new space for the hit information and passes the variable
  // track, and the pointers *vol and *hits to the AliITShit constructor
  // function.
  //
  TClonesArray &lhits = *fHits;
  new(lhits[fNhits++]) AliITShit(fIshunt,track,vol,hits);
}
//_____________________________________________________________________________
void AliITS::AddRealDigit(Int_t id, Int_t *digits) 
{
  // add a real digit - as coming from data

  TClonesArray &ldigits = *((TClonesArray*)(*fDtype)[id]);
  new(ldigits[fNdtype[id]++]) AliITSdigit(digits);

}
//_____________________________________________________________________________
void AliITS::AddSimDigit(Int_t id, AliITSdigit *d) 
{

  // add a simulated digit

  TClonesArray &ldigits = *((TClonesArray*)(*fDtype)[id]);

  switch(id)
  {
  case 0:
     new(ldigits[fNdtype[id]++]) AliITSdigitSPD(*((AliITSdigitSPD*)d));
     break;
  case 1:
     new(ldigits[fNdtype[id]++]) AliITSdigitSDD(*((AliITSdigitSDD*)d));
     break;
  case 2:
     new(ldigits[fNdtype[id]++]) AliITSdigitSSD(*((AliITSdigitSSD*)d));
     break;
  }

}

//_____________________________________________________________________________
void AliITS::AddSimDigit(Int_t id,Float_t phys,Int_t *digits,Int_t *tracks,Int_t *hits,Float_t *charges){

  // add a simulated digit to the list

  TClonesArray &ldigits = *((TClonesArray*)(*fDtype)[id]);
  switch(id)
  {
  case 0:
     new(ldigits[fNdtype[id]++]) AliITSdigitSPD(digits,tracks,hits);
     break;
  case 1:
     new(ldigits[fNdtype[id]++]) AliITSdigitSDD(phys,digits,tracks,hits,charges);
     break;
  case 2:
     new(ldigits[fNdtype[id]++]) AliITSdigitSSD(digits,tracks,hits);
     break;
  }
 
}

//_____________________________________________________________________________
void AliITS::AddCluster(Int_t id, AliITSRawCluster *c) 
{

  // add a cluster to the list

  TClonesArray &lcl = *((TClonesArray*)(*fCtype)[id]);

  switch(id)
  {
  case 0:
     new(lcl[fNctype[id]++]) AliITSRawClusterSPD(*((AliITSRawClusterSPD*)c));
     break;
  case 1:
     new(lcl[fNctype[id]++]) AliITSRawClusterSDD(*((AliITSRawClusterSDD*)c));
     break;
  case 2:
     new(lcl[fNctype[id]++]) AliITSRawClusterSSD(*((AliITSRawClusterSSD*)c));
     break;
  }

}


//_____________________________________________________________________________
void AliITS::AddRecPoint(const AliITSRecPoint &r)
{
  //
  // Add a reconstructed space point to the list
  //
  TClonesArray &lrecp = *fRecPoints;
  new(lrecp[fNRecPoints++]) AliITSRecPoint(r);
}
 

//____________________________________________
void AliITS::ResetDigits()
{
    //
    // Reset number of digits and the digits array for the ITS detector
    //

    if (!fDtype) return;

    Int_t i;
    for (i=0;i<fgkNTYPES;i++ ) {
	if ((*fDtype)[i])    ((TClonesArray*)(*fDtype)[i])->Clear();
	if (fNdtype)  fNdtype[i]=0;
    }
}

//____________________________________________
void AliITS::ResetDigits(Int_t i)
{
    //
    // Reset number of digits and the digits array for this branch
    //
  if ((*fDtype)[i])    ((TClonesArray*)(*fDtype)[i])->Clear();
  if (fNdtype)  fNdtype[i]=0;
}


//____________________________________________
void AliITS::ResetClusters()
{
    //
    // Reset number of clusters and the clusters array for ITS
    //

    Int_t i;
    for (i=0;i<fgkNTYPES;i++ ) {
	if ((*fCtype)[i])    ((TClonesArray*)(*fCtype)[i])->Clear();
	if (fNctype)  fNctype[i]=0;
    }

}

//____________________________________________
void AliITS::ResetClusters(Int_t i)
{
    //
    // Reset number of clusters and the clusters array for this branch
    //
	if ((*fCtype)[i])    ((TClonesArray*)(*fCtype)[i])->Clear();
	if (fNctype)  fNctype[i]=0;

}


//____________________________________________
void AliITS::ResetRecPoints()
{
    //
    // Reset number of rec points and the rec points array 
    //
    if (fRecPoints) fRecPoints->Clear();
    fNRecPoints = 0;

}

//_____________________________________________________________________________
Int_t AliITS::DistancetoPrimitive(Int_t , Int_t ){
  //
  // Distance from mouse to ITS on the screen. Dummy routine
  //     A dummy routine used by the ROOT macro display.C to allow for the
  // use of the mouse (pointing device) in the macro. In general this should
  // never be called. If it is it returns the number 9999 for any value of
  // x and y.
  //
  return 9999;
}

//_____________________________________________________________________________
void AliITS::Init(){
  //
  // Initialise ITS after it has been built
  //     This routine initializes the AliITS class. It is intended to be called
  // from the Init function in AliITSv?. Besides displaying a banner
  // indicating that it has been called it initializes the array fIdSens
  // and sets the default segmentation, response, digit and raw cluster classes
  // Therefore it should be called after a call to CreateGeometry.
  //
  Int_t i;

  cout << endl;
  for(i=0;i<30;i++) cout << "*";cout << " ITS_INIT ";
  for(i=0;i<30;i++) cout << "*";cout << endl;
//
  SetDefaults();
// TObjArray of TObjStrings
//  for(i=0;i<fIdN;i++) fIdSens[i] = gMC->VolId((fIdName->At(i))->GetName());
// Array of TStrings
  for(i=0;i<fIdN;i++) fIdSens[i] = gMC->VolId(fIdName[i]);
//
  for(i=0;i<70;i++) cout << "*";
  cout << endl;
}

//_____________________________________________________________________________
void AliITS::SetDefaults()
{
  // sets the default segmentation, response, digit and raw cluster classes

  cout << "AliITS::SetDefaults" << endl;

  AliITSDetType *iDetType;

  //SPD 

  iDetType = DetType(0);
  AliITSresponseSPD *resp0 = (AliITSresponseSPD*) iDetType->GetResponseModel();
  if (!iDetType->GetSegmentationModel()) {
    AliITSsegmentationSPD *seg0 = new AliITSsegmentationSPD(fITSgeom);
    SetSegmentationModel(0,seg0);
  } // end if 
  if (!resp0){
    resp0 = new AliITSresponseSPD();
    SetResponseModel(0,resp0);
  } // end if
  // set digit and raw cluster classes to be used

  const char *kData0 = resp0->DataType();
  if (strstr(kData0,"real")) {
      iDetType->ClassNames("AliITSdigit","AliITSRawClusterSPD");
  } else iDetType->ClassNames("AliITSdigitSPD","AliITSRawClusterSPD");

  // SDD
  iDetType = DetType(1);
  AliITSresponseSDD *resp1 = (AliITSresponseSDD*)iDetType->GetResponseModel();
  //printf("SetDefaults: iDetType %p\n",iDetType);
  if (!iDetType->GetSegmentationModel()) {
    AliITSsegmentationSDD *seg1 = new AliITSsegmentationSDD(fITSgeom,resp1);
    SetSegmentationModel(1,seg1); 
  } // end if
  //printf("SetDefaults: segm %p\n",iDetType->GetSegmentationModel());
  if (!resp1) {
    resp1 = new AliITSresponseSDD();
    SetResponseModel(1,resp1); 
  }
  //printf("SetDefaults: resp %p\n",iDetType->GetResponseModel());
  const char *kData1 = resp1->DataType();
  const char *kopt = resp1->ZeroSuppOption();
  if ((!strstr(kopt,"2D")) && (!strstr(kopt,"1D")) || strstr(kData1,"real") ) {
      iDetType->ClassNames("AliITSdigit","AliITSRawClusterSDD");
  } else iDetType->ClassNames("AliITSdigitSDD","AliITSRawClusterSDD");

  // SSD
  iDetType = DetType(2); 
  AliITSresponseSSD *resp2 = (AliITSresponseSSD*)iDetType->GetResponseModel();
  if (!iDetType->GetSegmentationModel()) {
    AliITSsegmentationSSD *seg2 = new AliITSsegmentationSSD(fITSgeom);
    SetSegmentationModel(2,seg2); 
  } // end if
  if (!resp2) {
    resp2 = new AliITSresponseSSD();
    SetResponseModel(2,resp2); 
  } // end if
  const char *kData2 = resp2->DataType();
  if (strstr(kData2,"real")) {
      iDetType->ClassNames("AliITSdigit","AliITSRawClusterSSD");
  } else iDetType->ClassNames("AliITSdigitSSD","AliITSRawClusterSSD");

  if (fgkNTYPES>3) {
    Warning("SetDefaults","Only the three basic detector types are initialised!");
  } // end if

}
//_____________________________________________________________________________
void AliITS::SetDefaultSimulation()
{
  // to be written

}
//_____________________________________________________________________________
void AliITS::SetDefaultClusterFinders()
{
  // to be written

}
//_____________________________________________________________________________

void AliITS::MakeTreeC(Option_t *option)
{
  // create a separate tree to store the clusters

  cout << "AliITS::MakeTreeC" << endl;

     char *optC = strstr(option,"C");
     if (optC && !fTreeC) fTreeC = new TTree("TC","Clusters in ITS");
     else return;

     Int_t buffersize = 4000;
     char branchname[30];

     char *det[3] = {"SPD","SDD","SSD"};

     // one branch for Clusters per type of detector
     Int_t i;
     for (i=0; i<fgkNTYPES ;i++) {
        if (fgkNTYPES==3) sprintf(branchname,"%sClusters%s",GetName(),det[i]);
	else  sprintf(branchname,"%sClusters%d",GetName(),i+1);
	if (fCtype   && fTreeC) {
	   TreeC()->Branch(branchname,&((*fCtype)[i]), buffersize);
	   cout << "Making Branch " << branchname;
	   cout << " for Clusters of detector type " << i+1 << endl;
	}	
     }

}

//_____________________________________________________________________________
void AliITS::GetTreeC(Int_t event)
{

  cout << "AliITS::GetTreeC" << endl;

  // get the clusters tree for this event and set the branch address
    char treeName[20];
    char branchname[30];

    char *det[3] = {"SPD","SDD","SSD"};

    ResetClusters();
    if (fTreeC) {
	  delete fTreeC;
    }

    sprintf(treeName,"TreeC%d",event);
    fTreeC = (TTree*)gDirectory->Get(treeName);


    TBranch *branch;
    if (fTreeC) {
        Int_t i;
	for (i=0; i<fgkNTYPES; i++) {
	   if (fgkNTYPES==3) sprintf(branchname,"%sClusters%s",GetName(),det[i]);
	   else  sprintf(branchname,"%sClusters%d",GetName(),i+1);
	   if (fCtype) {
		branch = fTreeC->GetBranch(branchname);
                if (branch) branch->SetAddress(&((*fCtype)[i]));
	    }
	}
    } else {
	Error("AliITS::GetTreeC",
		"cannot find Clusters Tree for event:%d\n",event);
    }

}
//_____________________________________________________________________________
void AliITS::MakeBranch(Option_t* option){
  //
  // Creates Tree branches for the ITS.
  //


  Int_t buffersize = 4000;
  char branchname[30];
  sprintf(branchname,"%s",GetName());

  AliDetector::MakeBranch(option);


// one branch for digits per type of detector
  
   char *det[3] = {"SPD","SDD","SSD"};

   char digclass[40];
   char clclass[40];

   Int_t i;
   for (i=0; i<fgkNTYPES ;i++) {
       AliITSDetType *iDetType=DetType(i); 
       iDetType->GetClassNames(digclass,clclass);
       //printf("i, digclass, recclass %d %s %s\n",i,digclass,clclass); 
       // digits
       (*fDtype)[i] = new TClonesArray(digclass,10000); 
       // clusters
       (*fCtype)[i] = new TClonesArray(clclass,10000); 
   }


  for (i=0; i<fgkNTYPES ;i++) {
      if (fgkNTYPES==3) sprintf(branchname,"%sDigits%s",GetName(),det[i]);
      else  sprintf(branchname,"%sDigits%d",GetName(),i+1);
      
      if (fDtype   && gAlice->TreeD()) {
	  gAlice->TreeD()->Branch(branchname,&((*fDtype)[i]), buffersize);
	  cout << "Making Branch " << branchname;
	  cout << " for digits of type "<< i+1 << endl;
      }	
  }

  // only one branch for rec points for all detector types
  sprintf(branchname,"%sRecPoints",GetName());

  fRecPoints=new TClonesArray("AliITSRecPoint",10000);

  if (fRecPoints && gAlice->TreeR()) {
    gAlice->TreeR()->Branch(branchname,&fRecPoints, buffersize);
    cout << "Making Branch " << branchname;
    cout << " for reconstructed space points" << endl;
  }	


}

//___________________________________________
void AliITS::SetTreeAddress()
{

  // Set branch address for the Trees.

  char branchname[30];
  AliDetector::SetTreeAddress();

  char *det[3] = {"SPD","SDD","SSD"};

  TBranch *branch;
  TTree *treeD = gAlice->TreeD();
  TTree *treeR = gAlice->TreeR();

  Int_t i;
  if (treeD) {
      for (i=0; i<fgkNTYPES; i++) {
	  if (fgkNTYPES==3) sprintf(branchname,"%sDigits%s",GetName(),det[i]);
	  else  sprintf(branchname,"%sDigits%d",GetName(),i+1);
	  if (fDtype) {
	      branch = treeD->GetBranch(branchname);
	      if (branch) branch->SetAddress(&((*fDtype)[i]));
	  }
      }
  }

 
  if (treeR) {
    sprintf(branchname,"%sRecPoints",GetName());
    if (fRecPoints) {
      branch = treeR->GetBranch(branchname);
      if (branch) branch->SetAddress(&fRecPoints);
    }
  }
  

}

//____________________________________________________________________________
void AliITS::InitModules(Int_t size,Int_t &nmodules){

  //initialize the modules array

  if(fITSmodules){ 
      fITSmodules->Delete();
      delete fITSmodules;
  }

    Int_t nl,indexMAX,index;

    if(size<=0){ // default to using data stored in AliITSgeom
	if(fITSgeom==0) {
	    Error("AliITS::InitModules",
	    	"in AliITS::InitModule fITSgeom not defined\n");
	    return;
	} // end if fITSgeom==0
	nl = fITSgeom->GetNlayers();
	indexMAX = fITSgeom->GetModuleIndex(nl,fITSgeom->GetNladders(nl),
					    fITSgeom->GetNdetectors(nl))+1;
	nmodules = indexMAX;
	fITSmodules = new TObjArray(indexMAX);
	for(index=0;index<indexMAX;index++){
		fITSmodules->AddAt( new AliITSmodule(index),index);
	} // end for index
    }else{
	fITSmodules = new TObjArray(size);
	for(index=0;index<size;index++) {
	    fITSmodules->AddAt( new AliITSmodule(index),index);
	}

        nmodules = size;
    } // end i size<=0
}

//____________________________________________________________________________
void AliITS::FillModules(Int_t evnt,Int_t bgrev,Int_t nmodules,Option_t *option,Text_t *filename){

  // fill the modules with the sorted by module hits; add hits from background
  // if option=Add


    static TTree *trH1;                 //Tree with background hits
    static TClonesArray *fHits2;        //List of hits for one track only

    static Bool_t first=kTRUE;
    static TFile *file;
    char *addBgr = strstr(option,"Add");


    if (addBgr ) {
	if(first) {
	    cout<<"filename "<<filename<<endl;
	    file=new TFile(filename);
	    cout<<"I have opened "<<filename<<" file "<<endl;
	    fHits2     = new TClonesArray("AliITShit",1000  );
	}	    
	first=kFALSE;
	file->cd();
	file->ls();
	// Get Hits Tree header from file
	if(fHits2) fHits2->Clear();
	if(trH1) delete trH1;
	trH1=0;
	
	char treeName[20];
	sprintf(treeName,"TreeH%d",bgrev);
	trH1 = (TTree*)gDirectory->Get(treeName);
        //printf("TrH1 %p of treename %s for event %d \n",trH1,treeName,bgrev);
	
	if (!trH1) {
	    Error("AliITS::FillModules",
	    "cannot find Hits Tree for event:%d\n",bgrev);
	}
	// Set branch addresses
	TBranch *branch;
	char branchname[20];
	sprintf(branchname,"%s",GetName());
	if (trH1 && fHits2) {
	    branch = trH1->GetBranch(branchname);
	    if (branch) branch->SetAddress(&fHits2);
	}

        // test
	//Int_t ntracks1 =(Int_t)TrH1->GetEntries();
	//printf("background - ntracks1 - %d\n",ntracks1);
   }

    Int_t npart = gAlice->GetEvent(evnt);
    if(npart<=0) return;
    TClonesArray *itsHits = this->Hits();
    Int_t lay,lad,det,index;
    AliITShit *itsHit=0;
    AliITSmodule *mod=0;

    TTree *iTH = gAlice->TreeH();
    Int_t ntracks =(Int_t) iTH->GetEntries();

    Int_t t,h;
    for(t=0; t<ntracks; t++){
	gAlice->ResetHits();
	iTH->GetEvent(t);
	Int_t nhits = itsHits->GetEntriesFast();
	//printf("nhits %d\n",nhits);
        if (!nhits) continue;
	for(h=0; h<nhits; h++){
	    itsHit = (AliITShit *)itsHits->UncheckedAt(h);
	    itsHit->GetDetectorID(lay,lad,det);
	    // temporarily index=det-1 !!!
	    if(fITSgeom) index = fITSgeom->GetModuleIndex(lay,lad,det);
	    else index=det-1;
	    //
	    mod = this->GetModule(index);
	    mod->AddHit(itsHit,t,h);
	} // end loop over hits 
    } // end loop over tracks

    // open the file with background
    
    if (addBgr ) {
          Int_t track,i;
          ntracks =(Int_t)trH1->GetEntries();
	    //printf("background - ntracks1 %d\n",ntracks);
	    //printf("background - Start loop over tracks \n");     
            //   Loop over tracks

	    for (track=0; track<ntracks; track++) {

		if (fHits2)       fHits2->Clear();
		trH1->GetEvent(track);
                //   Loop over hits
		for(i=0;i<fHits2->GetEntriesFast();++i) {

		    itsHit=(AliITShit*) (*fHits2)[i];
		    itsHit->GetDetectorID(lay,lad,det);
		    // temporarily index=det-1 !!!
		    if(fITSgeom) index = fITSgeom->GetModuleIndex(lay,lad,det);
		    else index=det-1;
		    //
		    mod = this->GetModule(index);
		    mod->AddHit(itsHit,track,i);
	       }  // end loop over hits
	    } // end loop over tracks

	    TTree *fAli=gAlice->TreeK();
            TFile *fileAli=0;
	    
	    if (fAli) fileAli =fAli->GetCurrentFile();
	    fileAli->cd();

    } // end if add

    //gObjectTable->Print();

}


//____________________________________________________________________________
void AliITS::HitsToDigits(Int_t evNumber,Int_t bgrev,Int_t size, Option_t *option, Option_t *opt,Text_t *filename)
{
    // keep galice.root for signal and name differently the file for 
    // background when add! otherwise the track info for signal will be lost !
  
   // the condition below will disappear when the geom class will be
   // initialised for all versions - for the moment it is only for v5 !
   // 7 is the SDD beam test version  
   Int_t ver = this->IsVersion(); 
   if(ver!=5 && ver!=7) return; 

   char *all = strstr(opt,"All");
   char *det[3] = {strstr(opt,"SPD"),strstr(opt,"SDD"),strstr(opt,"SSD")};

   Int_t nmodules;
   InitModules(size,nmodules); 
   FillModules(evNumber,bgrev,nmodules,option,filename);

   //TBranch *branch;
   AliITSsimulation* sim;
   //TObjArray *branches=gAlice->TreeD()->GetListOfBranches();
   AliITSgeom *geom = GetITSgeom();

   Int_t id,module;
   Int_t first,last;
   for (id=0;id<fgkNTYPES;id++) {
        if (!all && !det[id]) continue;
	//branch = (TBranch*)branches->UncheckedAt(id);
	AliITSDetType *iDetType=DetType(id); 
	sim = (AliITSsimulation*)iDetType->GetSimulationModel();
	if (!sim) {
           Error("HitsToDigits","The simulation class was not instantiated!");
           exit(1);
	   // or SetDefaultSimulation();
	}
	if(geom) {
	  first = geom->GetStartDet(id);
	  last = geom->GetLastDet(id);
	} else first=last=0;
	cout << "det type " << id << " first, last "<< first << last << endl;
	for(module=first;module<=last;module++) {
	    AliITSmodule *mod = (AliITSmodule *)fITSmodules->At(module);
	    sim->DigitiseModule(mod,module,evNumber);
	    // fills all branches - wasted disk space
	    gAlice->TreeD()->Fill(); 
	    ResetDigits();
	    // try and fill only the branch 
	    //branch->Fill();
	    //ResetDigits(id);
	} // loop over modules
   } // loop over detector types

   ClearModules();

   Int_t nentries=(Int_t)gAlice->TreeD()->GetEntries();
   cout << "nentries in TreeD" << nentries << endl;

   char hname[30];
   sprintf(hname,"TreeD%d",evNumber);
   gAlice->TreeD()->Write(hname);
   // reset tree
   gAlice->TreeD()->Reset();

}


//____________________________________________________________________________
void AliITS::DigitsToRecPoints(Int_t evNumber,Int_t lastentry,Option_t *opt)
{
  // cluster finding and reconstruction of space points
  
   // the condition below will disappear when the geom class will be
   // initialised for all versions - for the moment it is only for v5 !
   // 7 is the SDD beam test version  
   Int_t ver = this->IsVersion(); 
   if(ver!=5 && ver!=7) return; 

   char *all = strstr(opt,"All");
   char *det[3] = {strstr(opt,"SPD"),strstr(opt,"SDD"),strstr(opt,"SSD")};

   static Bool_t first=kTRUE;
   if (first) {
       MakeTreeC("C");
       first=kFALSE;
   }
 
   TTree *iTC=TreeC();

   //TBranch *branch;
   AliITSClusterFinder* rec;

   //TObjArray *branches=gAlice->TreeR()->GetListOfBranches();
   AliITSgeom *geom = GetITSgeom();

   Int_t id,module;
   for (id=0;id<fgkNTYPES;id++) {
        if (!all && !det[id]) continue;
	//branch = (TBranch*)branches->UncheckedAt(id);
	AliITSDetType *iDetType=DetType(id); 
	rec = (AliITSClusterFinder*)iDetType->GetReconstructionModel();
	if (!rec) {
           Error("DigitsToRecPoints","The cluster finder class was not instantiated!");
           exit(1);
	   // or SetDefaultClusterFinders();
	}
        TClonesArray *itsDigits  = this->DigitsAddress(id);

        Int_t first,last;
	if(geom) {
	  first = geom->GetStartDet(id);
	  last = geom->GetLastDet(id);
	} else first=last=0;
	//printf("first last %d %d\n",first,last);
	for(module=first;module<=last;module++) {
              this->ResetDigits();
              if (all) gAlice->TreeD()->GetEvent(lastentry+module);
	      else gAlice->TreeD()->GetEvent(lastentry+(module-first));
	      Int_t ndigits = itsDigits->GetEntriesFast();
	      if (ndigits) rec->FindRawClusters();
	      gAlice->TreeR()->Fill(); 
	      ResetRecPoints();
	      iTC->Fill();
              ResetClusters();
	      // try and fill only the branch 
	      //branch->Fill();
	      //ResetRecPoints(id);
	} // loop over modules
   } // loop over detector types


   Int_t nentries=(Int_t)gAlice->TreeR()->GetEntries();
   Int_t ncentries=(Int_t)iTC->GetEntries();
   cout << " nentries ncentries " << nentries << ncentries <<  endl;

   char hname[30];
   sprintf(hname,"TreeR%d",evNumber);
   gAlice->TreeR()->Write(hname);
   // reset tree
   gAlice->TreeR()->Reset();

   sprintf(hname,"TreeC%d",evNumber);
   iTC->Write(hname);
   iTC->Reset();
}


//____________________________________________________________________________
void AliITS::HitsToFastRecPoints(Int_t evNumber,Int_t bgrev,Int_t size,
Option_t *option,Option_t *opt,Text_t *filename)
{
    // keep galice.root for signal and name differently the file for 
    // background when add! otherwise the track info for signal will be lost !
  

   // the condition below will disappear when the geom class will be
   // initialised for all versions - for the moment it is only for v5 !  
   Int_t ver = this->IsVersion(); 
   if(ver!=5) return; 

   char *all = strstr(opt,"All");
   char *det[3] = {strstr(opt,"SPD"),strstr(opt,"SDD"),strstr(opt,"SSD")};

   Int_t nmodules;
   InitModules(size,nmodules);
   FillModules(evNumber,bgrev,nmodules,option,filename);


   AliITSsimulation* sim;
   AliITSgeom *geom = GetITSgeom();

   TRandom *random=new TRandom[9];
   random[0].SetSeed(111);
   random[1].SetSeed(222);
   random[2].SetSeed(333);		
   random[3].SetSeed(444);
   random[4].SetSeed(555);
   random[5].SetSeed(666);		
   random[6].SetSeed(777);
   random[7].SetSeed(888);
   random[8].SetSeed(999);		


   Int_t id,module;
   for (id=0;id<fgkNTYPES;id++) {
        if (!all && !det[id]) continue;
	AliITSDetType *iDetType=DetType(id); 
	sim = (AliITSsimulation*)iDetType->GetSimulationModel();
	if (!sim) {
           Error("HitsToFastPoints","The simulation class was not instantiated!");
           exit(1);
	   // or SetDefaultSimulation();
	}
	Int_t first = geom->GetStartDet(id);
	Int_t last = geom->GetLastDet(id);
	for(module=first;module<=last;module++) {
	    AliITSmodule *mod = (AliITSmodule *)fITSmodules->At(module);
	    sim->CreateFastRecPoints(mod,module,random);
	    gAlice->TreeR()->Fill(); 
	    ResetRecPoints();
	} // loop over modules
   } // loop over detector types


   ClearModules();

   //Int_t nentries=(Int_t)gAlice->TreeR()->GetEntries();

   char hname[30];
   sprintf(hname,"TreeR%d",evNumber);
   gAlice->TreeR()->Write(hname);
   // reset tree
   gAlice->TreeR()->Reset();

   delete [] random;

}


//____________________________________________________________________________
void AliITS::Streamer(TBuffer &R__b){
   // Stream an object of class AliITS.

   Int_t i;

   if (R__b.IsReading()) {
      Version_t R__v = R__b.ReadVersion();
      if (R__v) {
	  AliDetector::Streamer(R__b);
	  R__b >> fIdN;
	  R__b.ReadArray(fIdSens); 
  	  if(fIdName!=0) delete[] fIdName;  // Array of TStrings
    	  fIdName    = new TString[fIdN];
	  for(i=0;i<fIdN;i++) fIdName[i].Streamer(R__b);
	  R__b >> fITSgeom;
	  R__b >> fITSmodules;
	  R__b >> fEuclidOut;
	  R__b >> fMajorVersion;
	  R__b >> fMinorVersion;
	  R__b >> fDetTypes;
	  R__b >> fDtype;
	  delete []fNdtype; 
	  fNdtype = new Int_t[fgkNTYPES];
	  R__b.ReadFastArray(fNdtype,fgkNTYPES);
	  R__b >> fCtype;
	  delete []fNctype; 
	  fNctype = new Int_t[fgkNTYPES];
	  R__b.ReadFastArray(fNctype,fgkNTYPES);
	  R__b >> fRecPoints;
	  R__b >> fNRecPoints;
	  R__b >> fTreeC;
      } // end if R__v
   } else { // writing
      R__b.WriteVersion(AliITS::IsA());
      AliDetector::Streamer(R__b);
      R__b << fIdN;
      R__b.WriteArray(fIdSens,fIdN); 
      for(i=0;i<fIdN;i++) fIdName[i].Streamer(R__b);
      R__b << fITSgeom;
      R__b << fITSmodules;
      R__b << fEuclidOut;
      R__b << fMajorVersion;
      R__b << fMinorVersion;
      R__b << fDetTypes;
      R__b << fDtype;
      R__b.WriteFastArray(fNdtype,fgkNTYPES);
      R__b << fCtype;
      R__b.WriteFastArray(fNctype,fgkNTYPES);
      R__b << fRecPoints;
      R__b << fNRecPoints;
      R__b << fTreeC;
   } // end if

}