/**************************************************************************
 * 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.                  *
 **************************************************************************/

/* $Id$ */

//_________________________________________________________________________
//*-- Author :  Dmitri Peressounko (SUBATECH & Kurchatov Institute) 
//////////////////////////////////////////////////////////////////////////////
// This TTask performs digitization of Summable digits (in the PHOS case it is just
// the sum of contributions from all primary particles into a given cell). 
// In addition it performs mixing of summable digits from different events.
// The name of the TTask is also the title of the branch that will contain 
// the created SDigits
// The title of the TTAsk is the name of the file that contains the hits from
// which the SDigits are created
//
// For each event two branches are created in TreeD:
//   "PHOS" - list of digits
//   "AliPHOSDigitizer" - AliPHOSDigitizer with all parameters used in digitization
//
// Note, that one can set a title for new digits branch, and repeat digitization with
// another set of parameters.
//
// Use case:
// root[0] AliPHOSDigitizer * d = new AliPHOSDigitizer() ;
// root[1] d->ExecuteTask()             
// Warning in <TDatabasePDG::TDatabasePDG>: object already instantiated
//                       //Digitizes SDigitis in all events found in file galice.root 
//
// root[2] AliPHOSDigitizer * d1 = new AliPHOSDigitizer("galice1.root") ;  
//                       // Will read sdigits from galice1.root
// root[3] d1->MixWith("galice2.root")       
// Warning in <TDatabasePDG::TDatabasePDG>: object already instantiated
//                       // Reads another set of sdigits from galice2.root
// root[3] d1->MixWith("galice3.root")       
//                       // Reads another set of sdigits from galice3.root
// root[4] d->ExecuteTask("deb timing")    
//                       // Reads SDigits from files galice1.root, galice2.root ....
//                       // mixes them and stores produced Digits in file galice1.root          
//                       // deb - prints number of produced digits
//                       // deb all - prints list of produced digits
//                       // timing  - prints time used for digitization
//

// --- ROOT system ---
#include "TFile.h"
#include "TTree.h"
#include "TSystem.h"
#include "TROOT.h"
#include "TFolder.h"
#include "TObjString.h"
#include "TGeometry.h"
#include "TBenchmark.h"

// --- Standard library ---

// --- AliRoot header files ---
#include "AliRun.h"
#include "AliHeader.h"
#include "AliStream.h"
#include "AliRunDigitizer.h"
#include "AliPHOSDigit.h"
#include "AliPHOS.h"
#include "AliPHOSGetter.h"
#include "AliPHOSDigitizer.h"
#include "AliPHOSSDigitizer.h"
#include "AliPHOSGeometry.h"
#include "AliPHOSTick.h"

ClassImp(AliPHOSDigitizer)


//____________________________________________________________________________ 
  AliPHOSDigitizer::AliPHOSDigitizer() 
{
  // ctor
  InitParameters() ; 
  fDefaultInit = kTRUE ;
  fManager = 0 ;                     // We work in the standalong mode

 }

//____________________________________________________________________________ 
AliPHOSDigitizer::AliPHOSDigitizer(const char *headerFile, const char * name, const Bool_t toSplit)
{
  // ctor

  SetTitle(headerFile) ;
  SetName(name) ;
  fManager = 0 ;                     // We work in the standalong mode
  fSplitFile= 0 ; 
  InitParameters() ; 
  fToSplit = toSplit ;
  Init() ;
  fDefaultInit = kFALSE ; 
}

//____________________________________________________________________________ 
AliPHOSDigitizer::AliPHOSDigitizer(AliRunDigitizer * ard):AliDigitizer(ard)
{
  // ctor
  SetTitle(ard->GetInputFileName(0,0)) ;
  InitParameters() ; 
  fDefaultInit = kFALSE ; 
  fSplitFile   = 0 ; 

  if (ard->GetOutputFile()) {
    SetName(ard->GetOutputFile().Data());
    fToSplit = kTRUE ;
  } else {
    SetName("Default") ;
    fToSplit = kFALSE ;
  }
}

//____________________________________________________________________________ 
  AliPHOSDigitizer::~AliPHOSDigitizer()
{
  // dtor
     
   fSplitFile = 0 ; 
}

//____________________________________________________________________________
void AliPHOSDigitizer::Digitize(const Int_t event) 
{ 
  
  // Makes the digitization of the collected summable digits.
  //  It first creates the array of all PHOS modules
  //  filled with noise (different for EMC, CPV and PPSD) and
  //  then adds contributions from SDigits. 
  // This design avoids scanning over the list of digits to add 
  // contribution to new SDigits only.

  AliPHOSGetter * gime = AliPHOSGetter::GetInstance() ; 
  TClonesArray * digits = gime->Digits(GetName()) ; 

  digits->Clear() ;

  const AliPHOSGeometry *geom = gime->PHOSGeometry() ; 
  //Making digits with noise, first EMC
  Int_t nEMC = geom->GetNModules()*geom->GetNPhi()*geom->GetNZ();
  
  Int_t nCPV ;
  Int_t absID ;
  TString name      =  geom->GetName() ;
  
  nCPV = nEMC + geom->GetNumberOfCPVPadsZ()*geom->GetNumberOfCPVPadsPhi()*
    geom->GetNModules() ;

  digits->Expand(nCPV) ;

  // get first the sdigitizer from the tasks list (must have same name as the digitizer)
  const AliPHOSSDigitizer * sDigitizer = gime->SDigitizer(GetName()); 
  if ( !sDigitizer) {
    Fatal("Digitize", "SDigitizer with name %s not found", GetName() ) ; 
  }
    
  // loop through the sdigits posted to the White Board and add them to the noise
  TCollection * folderslist = gime->SDigitsFolder()->GetListOfFolders() ; 
  TIter next(folderslist) ; 
  TFolder * folder = 0 ; 
  TClonesArray * sdigits = 0 ;
  Int_t input = 0 ;
  TObjArray * sdigArray = new TObjArray(2) ;
  while ( (folder = (TFolder*)next()) ) { 
    if ( (sdigits = (TClonesArray*)folder->FindObject(GetName()) ) ) {
      TString fileName(folder->GetName()) ;
      fileName.ReplaceAll("_","/") ;
//       Info("Digitize", "Adding SDigits %s from %s", GetName(), fileName() ) ;  
      sdigArray->AddAt(sdigits, input) ;
      input++ ;
    }
  }

  //Find the first crystall with signal
  Int_t nextSig = 200000 ; 
  Int_t i;
  for(i=0; i<input; i++){
    sdigits = (TClonesArray *)sdigArray->At(i) ;
    if ( !sdigits->GetEntriesFast() )
      continue ; 
    Int_t curNext = ((AliPHOSDigit *)sdigits->At(0))->GetId() ;
     if(curNext < nextSig) 
       nextSig = curNext ;
  }

  TArrayI index(input) ;
  index.Reset() ;  //Set all indexes to zero

  AliPHOSDigit * digit ;
  AliPHOSDigit * curSDigit ;

  TClonesArray * ticks = new TClonesArray("AliPHOSTick",1000) ;

  //Put Noise contribution
  for(absID = 1; absID <= nEMC; absID++){
    Float_t noise = gRandom->Gaus(0., fPinNoise) ; 
    new((*digits)[absID-1]) AliPHOSDigit( -1,absID,sDigitizer->Digitize(noise), TimeOfNoise() ) ;
    //look if we have to add signal?
    digit = (AliPHOSDigit *) digits->At(absID-1) ;
 
    if(absID==nextSig){
      //Add SDigits from all inputs 
      ticks->Clear() ;
      Int_t contrib = 0 ;
      Float_t a = digit->GetAmp() ;
      Float_t b = TMath::Abs( a /fTimeSignalLength) ;
      //Mark the beginnign of the signal
      new((*ticks)[contrib++]) AliPHOSTick(digit->GetTime(),0, b);  
      //Mark the end of the ignal     
      new((*ticks)[contrib++]) AliPHOSTick(digit->GetTime()+fTimeSignalLength, -a, -b); 

      //loop over inputs
      for(i=0; i<input; i++){
	if(((TClonesArray *)sdigArray->At(i))->GetEntriesFast() > index[i] )
	  curSDigit = (AliPHOSDigit*)((TClonesArray *)sdigArray->At(i))->At(index[i]) ; 	
	else
	  curSDigit = 0 ;
	//May be several digits will contribute from the same input
	while(curSDigit && curSDigit->GetId() == absID){	   
	  //Shift primary to separate primaries belonging different inputs
	  Int_t primaryoffset ;
	  if(fManager)
	    primaryoffset = fManager->GetMask(i) ; 
	  else
	    primaryoffset = 10000000*i ;
	  curSDigit->ShiftPrimary(primaryoffset) ;
	  
	  a = curSDigit->GetAmp() ;
	  b = a /fTimeSignalLength ;
	  new((*ticks)[contrib++]) AliPHOSTick(curSDigit->GetTime(),0, b);  
	  new((*ticks)[contrib++]) AliPHOSTick(curSDigit->GetTime()+fTimeSignalLength, -a, -b); 

	  *digit = *digit + *curSDigit ;  //add energies

	  index[i]++ ;
	  if(((TClonesArray *)sdigArray->At(i))->GetEntriesFast() > index[i] )
	    curSDigit = (AliPHOSDigit*)((TClonesArray *)sdigArray->At(i))->At(index[i]) ; 	
	  else
	    curSDigit = 0 ;
	}
      }

      //calculate and set time
      Float_t time = FrontEdgeTime(ticks) ;
      digit->SetTime(time) ;

      //Find next signal module
      nextSig = 200000 ;
      for(i=0; i<input; i++){
	sdigits = ((TClonesArray *)sdigArray->At(i)) ;
	Int_t curNext = nextSig ;
	if(sdigits->GetEntriesFast() > index[i] ){
	  curNext = ((AliPHOSDigit *) sdigits->At(index[i]))->GetId() ;
	  
	}
	if(curNext < nextSig) nextSig = curNext ;
      }
    }
  }
  
  ticks->Delete() ;
  delete ticks ;


  //Now CPV digits (different noise and no timing)
  for(absID = nEMC+1; absID <= nCPV; absID++){
    Float_t noise = gRandom->Gaus(0., fCPVNoise) ; 
    new((*digits)[absID-1]) AliPHOSDigit( -1,absID,sDigitizer->Digitize(noise), TimeOfNoise() ) ;
    //look if we have to add signal?
    if(absID==nextSig){
      digit = (AliPHOSDigit *) digits->At(absID-1) ;
      //Add SDigits from all inputs
      for(i=0; i<input; i++){
	if(((TClonesArray *)sdigArray->At(i))->GetEntriesFast() > index[i] )
	  curSDigit = (AliPHOSDigit*)((TClonesArray *)sdigArray->At(i))->At(index[i]) ; 	
	else
	  curSDigit = 0 ;

	//May be several digits will contribute from the same input
	while(curSDigit && curSDigit->GetId() == absID){	   
	  //Shift primary to separate primaries belonging different inputs
	  Int_t primaryoffset ;
	  if(fManager)
	    primaryoffset = fManager->GetMask(i) ; 
	  else
	    primaryoffset = 10000000*i ;
	  curSDigit->ShiftPrimary(primaryoffset) ;

	  //add energies
	  *digit = *digit + *curSDigit ;  
	  index[i]++ ;
	  if(((TClonesArray *)sdigArray->At(i))->GetEntriesFast() > index[i] )
	    curSDigit = (AliPHOSDigit*)((TClonesArray *)sdigArray->At(i))->At(index[i]) ; 	
	  else
	    curSDigit = 0 ;
	}
      }

      //Find next signal module
      nextSig = 200000 ;
      for(i=0; i<input; i++){
	sdigits = (TClonesArray *)sdigArray->At(i) ;
	Int_t curNext = nextSig ;
	if(sdigits->GetEntriesFast() > index[i] )
	  curNext = ((AliPHOSDigit *) sdigits->At(index[i]))->GetId() ;
	if(curNext < nextSig) nextSig = curNext ;
      }
      
    }
  }
  delete sdigArray ; //We should not delete its contents
  
  
  
  //remove digits below thresholds
  for(i = 0; i < nEMC ; i++){
    digit = dynamic_cast<AliPHOSDigit*>( digits->At(i) ) ;
    if(sDigitizer->Calibrate( digit->GetAmp() ) < fEMCDigitThreshold)
      digits->RemoveAt(i) ;
    else
      digit->SetTime(gRandom->Gaus(digit->GetTime(),fTimeResolution) ) ;
  }


  for(i = nEMC; i < nCPV ; i++)
    if(sDigitizer->Calibrate(((AliPHOSDigit*)digits->At(i))->GetAmp()) < fCPVDigitThreshold)
      digits->RemoveAt(i) ;
    
  digits->Compress() ;  
  
  Int_t ndigits = digits->GetEntriesFast() ;
  digits->Expand(ndigits) ;

  //Set indexes in list of digits and make true digitization of the energy
  for (i = 0 ; i < ndigits ; i++) { 
    digit = dynamic_cast<AliPHOSDigit*>( digits->At(i) ) ; 
    digit->SetIndexInList(i) ;     
    Float_t energy = sDigitizer->Calibrate(digit->GetAmp()) ;
    digit->SetAmp(DigitizeEnergy(energy,digit->GetId()) ) ;
  }

}

//____________________________________________________________________________
Int_t AliPHOSDigitizer::DigitizeEnergy(Float_t energy, Int_t absId)
{
  Int_t chanel ;
  if(absId <= fEmcCrystals){ //digitize as EMC 
    chanel = (Int_t) TMath::Ceil((energy - fADCpedestalEmc)/fADCchanelEmc) ;       
    if(chanel > fNADCemc ) chanel =  fNADCemc ;
  }
  else{ //Digitize as CPV
    chanel = (Int_t) TMath::Ceil((energy - fADCpedestalCpv)/fADCchanelCpv) ;       
    if(chanel > fNADCcpv ) chanel =  fNADCcpv ;
  }
  return chanel ;
}

//____________________________________________________________________________
void AliPHOSDigitizer::Exec(Option_t *option) 
{ 
  // Managing method

  if(strcmp(GetName(), "") == 0 )   
    Init() ;
  if (strstr(option,"print")) {
    Print("");
    return ; 
  }
  
  if(strstr(option,"tim"))
    gBenchmark->Start("PHOSDigitizer");

  AliPHOSGetter * gime = AliPHOSGetter::GetInstance() ;
  
  Int_t nevents ;
  
  TTree * treeD ;
  
  if(fManager){
    treeD = fManager->GetTreeD() ;
    nevents = 1 ;    // Will process only one event
    
    //Check, if this branch already exits
    if (treeD) { 
      TObjArray * lob = (TObjArray*)treeD->GetListOfBranches() ;
      TIter next(lob) ; 
      TBranch * branch = 0 ;  
      Bool_t phosfound = kFALSE, digitizerfound = kFALSE ; 
      
      while ( (branch = (TBranch*)next()) && (!phosfound || !digitizerfound) ) {
	if ( (strcmp(branch->GetName(), "PHOS")==0) && 
	     (strcmp(branch->GetTitle(), GetName())==0) ) 
	  phosfound = kTRUE ;
	
	else if ( (strcmp(branch->GetName(), "AliPHOSDigitizer")==0) && 
		  (strcmp(branch->GetTitle(), GetName())==0) ) 
	  digitizerfound = kTRUE ; 
      }
      
      if ( phosfound ) {
	Error("Exec", "Digits branch with name %s already exists", GetName() ) ;
	return ; 
      }   
      if ( digitizerfound ) {
	Error("Exec", "Digitizer branch with name %s already exists", GetName() );
	return ; 
      }
    }   
  }
  else { //PHOS standalone
    if(gime->BranchExists("Digits") ) 
      return ;
    nevents=gime->MaxEvent() ;
  }
  
  Int_t ievent ;
  
  for(ievent = 0; ievent < nevents; ievent++){
  
    if(fManager){

      Int_t input ;
      for(input = 0 ; input < fManager->GetNinputs(); input ++){
  	TTree * treeS = fManager->GetInputTreeS(input) ;
	if(!treeS){
	  Error("Exec", "No Input") ;  
	  return ;
	}
	gime->ReadTreeS(treeS,input) ;
      }

    }
    else
      gime->Event(ievent,"S") ;
    
    Digitize(ievent) ; //Add prepared SDigits to digits and add the noise
    
    WriteDigits(ievent) ;
    
    if(strstr(option,"deb"))
      PrintDigits(option);
    
    //increment the total number of Digits per run 
    fDigitsInRun += gime->Digits()->GetEntriesFast() ;  
  }
   
  if(strstr(option,"tim")){
    gBenchmark->Stop("PHOSDigitizer");
    TString message ; 
    message = "  took %f seconds for Digitizing %f seconds per event\n" ; 
    Info("Exec", message.Data(), 
	 gBenchmark->GetCpuTime("PHOSDigitizer"), 
	 gBenchmark->GetCpuTime("PHOSDigitizer")/nevents ); 
  } 
}

//____________________________________________________________________________ 
Float_t AliPHOSDigitizer::FrontEdgeTime(TClonesArray * ticks) 
{ // 
  ticks->Sort() ; //Sort in accordance with times of ticks
  TIter it(ticks) ;
  AliPHOSTick * ctick = (AliPHOSTick *) it.Next() ;
  Float_t time = ctick->CrossingTime(fTimeThreshold) ;    

  AliPHOSTick * t ;  
  while((t=(AliPHOSTick*) it.Next())){
    if(t->GetTime() < time)  //This tick starts before crossing
      *ctick+=*t ;
    else
      return time ;

    time = ctick->CrossingTime(fTimeThreshold) ;    
  }
  return time ;
}

//____________________________________________________________________________ 
Bool_t AliPHOSDigitizer::Init()
{
  // Makes all memory allocations

  if( strcmp(GetTitle(), "") == 0 )
    SetTitle("galice.root") ;
  
  AliPHOSGetter * gime = AliPHOSGetter::GetInstance(GetTitle(), GetName(), fToSplit) ; 
  if ( gime == 0 ) {
    Error("Init", "Could not obtain the Getter object !") ; 
    return kFALSE;
  } 
  
  const AliPHOSGeometry * geom = gime->PHOSGeometry() ;

  fEmcCrystals = geom->GetNModules() *  geom->GetNCristalsInModule() ;
  
  // Post Digits to the white board
  gime->PostDigits(GetName() ) ;   
  
  // Post Digitizer to the white board
  gime->PostDigitizer(this) ;

  fSplitFile = 0 ;
  if(fToSplit){
    // construct the name of the file as /path/PHOS.SDigits.root
    //First - extract full path if necessary
    TString digitsFileName(GetTitle()) ;
    Ssiz_t islash = digitsFileName.Last('/') ;
    if(islash<digitsFileName.Length())
      digitsFileName.Remove(islash+1,digitsFileName.Length()) ;
    else
      digitsFileName="" ;
    // Next - append the file name 
    digitsFileName+="PHOS.Digits." ;
    if((strcmp(GetName(),"Default")!=0)&&(strcmp(GetName(),"")!=0)){
      digitsFileName+=GetName() ;
      digitsFileName+="." ;
    }
    digitsFileName+="root" ;
    // Finally - check if the file already opened or open the file
    fSplitFile = static_cast<TFile*>(gROOT->GetFile(digitsFileName.Data()));   
    if(!fSplitFile)
      fSplitFile =  TFile::Open(digitsFileName.Data(),"update") ;
  }
  
  //Mark that we will use current header file
  if(!fManager){
    gime->PostSDigits(GetName(),GetTitle()) ;
    gime->PostSDigitizer(GetName(),GetTitle()) ;
  }
  return kTRUE ;
}

//____________________________________________________________________________ 
void AliPHOSDigitizer::InitParameters()
{
  fPinNoise           = 0.004 ;
  fEMCDigitThreshold  = 0.012 ;
  fCPVNoise           = 0.01;
  fCPVDigitThreshold  = 0.09 ;
  fTimeResolution     = 0.5e-9 ;
  fTimeSignalLength   = 1.0e-9 ;
  fDigitsInRun  = 0 ; 
  fADCchanelEmc = 0.0015;        // width of one ADC channel in GeV
  fADCpedestalEmc = 0.005 ;      //
  fNADCemc = (Int_t) TMath::Power(2,16) ;  // number of channels in EMC ADC

  fADCchanelCpv = 0.0012 ;          // width of one ADC channel in CPV 'popugais'
  fADCpedestalCpv = 0.012 ;         // 
  fNADCcpv = (Int_t) TMath::Power(2,12);      // number of channels in CPV ADC

  fTimeThreshold = 0.001*10000000 ; //Means 1 MeV in terms of SDigits amplitude
    
}

//__________________________________________________________________
void AliPHOSDigitizer::MixWith(const char* headerFile)
{
  // Allows to produce digits by superimposing background and signal event.
  // It is assumed, that headers file with SIGNAL events is opened in 
  // the constructor. 
  // Sets the BACKGROUND event, with which the SIGNAL event is to be mixed 
  // Thus we avoid writing (changing) huge and expensive 
  // backgound files: all output will be writen into SIGNAL, i.e. 
  // opened in constructor file. 
  //
  // One can open as many files to mix with as one needs.
  // However only Sdigits with the same name (i.e. constructed with the same SDigitizer)
  // can be mixed.

  if( strcmp(GetName(), "") == 0 )
    Init() ;

  if(fManager){
    Warning("MixWith", "Can not use this method under AliRunDigitizer\n" ) ;
    return ;
  }
  
  // check if the specified SDigits do not already exist on the White Board:
  // //Folders/RunMC/Event/Data/PHOS/SDigits/headerFile/sdigitsname

  AliPHOSGetter * gime = AliPHOSGetter::GetInstance() ; 
  TString path = gime->SDigitsFolder()->GetName() ; 

  // before it was ???? "Folders/RunMC/Event/Data/PHOS/SDigits" ; 
  path += headerFile ; 
  path += "/" ; 
  path += GetName() ;
  if ( gROOT->FindObjectAny(path.Data()) ) {
    Warning("MixWith", "Entry already exists, do not add\n" ) ;
    return;
  }
  
  gime->PostSDigits(GetName(),headerFile) ;
  
  // check if the requested file is already open or exist and if SDigits Branch exist
  TFile * file = (TFile*)gROOT->FindObject(headerFile); 
  if ( !file ) { 
    file = new TFile(headerFile, "READ") ; 
    if (!file) { 
      Error("MixWith", "File %s does not exist\n", headerFile ); 
      return ; 
    }
  }
}

//__________________________________________________________________
void AliPHOSDigitizer::Print(Option_t* option)const 
{
  // Print Digitizer's parameters
  if( strcmp(GetName(), "") != 0 ){

    TString message("\n-------------------") ; 
    message += GetName() ; 
    message += "-------------\n" ;

    const Int_t nStreams = GetNInputStreams() ; 
    if (nStreams) {
      Int_t index = 0 ;  
      for (index = 0 ; index < nStreams ; index++) {  
	message += "Adding SDigits " ; 
	message += GetName() ;
	message += "from " ; 
	message += fManager->GetInputFileName(index, 0) ; 
      }
      message += "\nWriting digits to " ; 
      message += fManager->GetInputFileName(0, 0) ;   
    } else { 
      //       AliPHOSGetter * gime = AliPHOSGetter::GetInstance() ;  
      //       gime->Folder("sdigits")  ;
      //       TCollection * folderslist = gime->Folder("sdigits")->GetListOfFolders() ; 
      //       TIter next(folderslist) ; 
      //       TFolder * folder = 0 ; 
      
      //       while ( (folder = (TFolder*)next()) ) {
      // 	if ( folder->FindObject(GetName())  ) 
      //      }
      message += "\nWriting digits to " ;
      message += GetTitle() ;
    }    
    message += "\nWith following parameters:\n" ;
    message += "     Electronics noise in EMC (fPinNoise) = %f\n" ; 
    message += "  Threshold  in EMC  (fEMCDigitThreshold) = %f\n" ; 
    message += "                 Noise in CPV (fCPVNoise) = %f\n" ;
    message += "    Threshold in CPV (fCPVDigitThreshold) = %f\n" ;
    message += "---------------------------------------------------\n" ; 
    Info("Print", message.Data(),  
	 fPinNoise, 
	 fEMCDigitThreshold, 
	 fCPVNoise, 
	 fCPVDigitThreshold ) ; 
  }
  else
    Info("Print", "AliPHOSDigitizer not initialized\n" ) ;
  
}
 
//__________________________________________________________________
 void AliPHOSDigitizer::PrintDigits(Option_t * option)
{
  // Print a table of digits
  
  AliPHOSGetter * gime = AliPHOSGetter::GetInstance() ; 
  TClonesArray * digits = gime->Digits() ; 
  
  TString message ; 
  message  = "\nevent " ;
  message += gAlice->GetEvNumber() ;
  message += "\n       Number of entries in Digits list " ;  
  message += digits->GetEntriesFast()  ;  
  char * tempo = new char[8192]; 
 
  if(strstr(option,"all")||strstr(option,"EMC")){  
    //loop over digits
    AliPHOSDigit * digit;
    message += "\nEMC digits (with primaries):\n"  ;
    message += "\n   Id  Amplitude    Time          Index Nprim: Primaries list \n" ;    
    Int_t maxEmc = gime->PHOSGeometry()->GetNModules()*gime->PHOSGeometry()->GetNCristalsInModule() ;
    Int_t index ;
    for (index = 0 ; (index < digits->GetEntriesFast()) && 
	   (((AliPHOSDigit * )  digits->At(index))->GetId() <= maxEmc) ; index++) {
      digit = (AliPHOSDigit * )  digits->At(index) ;
      if(digit->GetNprimary() == 0) 
	continue;
      sprintf(tempo, "\n%6d  %8d    %6.5e %4d      %2d :",
	      digit->GetId(), digit->GetAmp(), digit->GetTime(), digit->GetIndexInList(), digit->GetNprimary()) ;  
      message += tempo ; 
      Int_t iprimary;
      for (iprimary=0; iprimary<digit->GetNprimary(); iprimary++) {
	sprintf(tempo, "%d ",digit->GetPrimary(iprimary+1) ) ; 
	message += tempo ; 
      }    
    }
  }
  
  if(strstr(option,"all")||strstr(option,"CPV")){
    
    //loop over CPV digits
    AliPHOSDigit * digit;
    message += "\nCPV digits:\n" ;
    message += "\n   Id  Amplitude    Index Nprim: Primaries list \n" ;    

    Int_t maxEmc = gime->PHOSGeometry()->GetNModules()*gime->PHOSGeometry()->GetNCristalsInModule() ;
    Int_t index ;
    for (index = 0 ; index < digits->GetEntriesFast(); index++) {
      digit = (AliPHOSDigit * )  digits->At(index) ;
      if(digit->GetId() > maxEmc){
	sprintf(tempo, "\n%6d  %8d    %4d      %2d :",
		digit->GetId(), digit->GetAmp(), digit->GetIndexInList(), digit->GetNprimary()) ;  
	message += tempo ; 
	Int_t iprimary;
	for (iprimary=0; iprimary<digit->GetNprimary(); iprimary++) {
	  sprintf(tempo, "%d ",digit->GetPrimary(iprimary+1) ) ; 
	  message += tempo ; 
	}    
      }
    }
  }
  delete tempo ; 
  Info("Print", message.Data() ) ; 
}

//__________________________________________________________________
Float_t AliPHOSDigitizer::TimeOfNoise(void)
{  // Calculates the time signal generated by noise
  //to be rewritten, now returns just big number
  return 1. ;

}

//____________________________________________________________________________
void AliPHOSDigitizer::WriteDigits(Int_t event)
{

  // Makes TreeD in the output file. 
  // Check if branch already exists: 
  //   if yes, exit without writing: ROOT TTree does not support overwriting/updating of 
  //      already existing branches. 
  //   else creates branch with Digits, named "PHOS", title "...",
  //      and branch "AliPHOSDigitizer", with the same title to keep all the parameters
  //      and names of files, from which digits are made.

  AliPHOSGetter * gime = AliPHOSGetter::GetInstance() ; 
  const TClonesArray * digits = gime->Digits(GetName()) ; 
  TTree * treeD ;
  
  if(fManager) 
    treeD = fManager->GetTreeD() ;
  else {
    if((gAlice->TreeD() == 0) || (fSplitFile))  // we should not create TreeD if it is already here
      gAlice->MakeTree("D", fSplitFile);       // We overwrite TreeD in split file in the case of second reconstruction
    if(fSplitFile)
      fSplitFile->cd() ;
    treeD = gAlice->TreeD();
  }
  
  // -- create Digits branch
  Int_t bufferSize = 32000 ;    
  TBranch * digitsBranch = treeD->Branch("PHOS",&digits,bufferSize);
  digitsBranch->SetTitle(GetName());
  
  // -- Create Digitizer branch
  Int_t splitlevel = 0 ;
  const AliPHOSDigitizer * d = dynamic_cast<const AliPHOSDigitizer *>(gime->Digitizer()) ;
  TBranch * digitizerBranch = treeD->Branch("AliPHOSDigitizer", "AliPHOSDigitizer", &d,bufferSize,splitlevel); 
  digitizerBranch->SetTitle(GetName());

  digitsBranch->Fill() ;
  digitizerBranch->Fill() ; 
  treeD->AutoSave() ; 
}