/**************************************************************************
 * Copyright(c) 2007, 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: $ */

// This class extracts the signal parameters (energy, time, quality)
// from ALTRO samples. Energy is in ADC counts, time is in time bin units.
// A coarse algorithm takes the energy as the maximum
// sample, time is the first sample index, and the quality is the number
// of bunches in the signal.
// 
//     AliPHOSRawFitterv0 *fitterv0=new AliPHOSRawFitterv0();
//     fitterv0->SetChannelGeo(module,cellX,cellZ,caloFlag);
//     fitterv0->SetCalibData(fgCalibData) ;
//     fitterv0->Eval(sig,sigStart,sigLength);
//     Double_t amplitude = fitterv0.GetEnergy();
//     Double_t time      = fitterv0.GetTime();
//     Bool_t   isLowGain = fitterv0.GetCaloFlag()==0;

// Author: Yuri Kharlov

// --- ROOT system ---
#include "TArrayI.h"
#include "TMath.h"
#include "TObject.h"

// --- AliRoot header files ---
#include "AliPHOSRawFitterv0.h"
#include "AliPHOSCalibData.h"
#include "AliLog.h"

ClassImp(AliPHOSRawFitterv0)

//-----------------------------------------------------------------------------
AliPHOSRawFitterv0::AliPHOSRawFitterv0():
  TObject(),
  fModule(0),
  fCellX(0),
  fCellZ(0),
  fCaloFlag(0),
  fNBunches(0),
  fPedSubtract(kFALSE),
  fEnergy(-111),
  fTime(-111),
  fQuality(0.),
  fPedestalRMS(0.),
  fAmpOffset(0),
  fAmpThreshold(0),
  fOverflow(kFALSE),
  fCalibData(0)
{
  //Default constructor
}

//-----------------------------------------------------------------------------
AliPHOSRawFitterv0::~AliPHOSRawFitterv0()
{
  //Destructor
}

//-----------------------------------------------------------------------------
AliPHOSRawFitterv0::AliPHOSRawFitterv0(const AliPHOSRawFitterv0 &phosFitter ):
  TObject(),
  fModule      (phosFitter.fModule),
  fCellX       (phosFitter.fCellX),
  fCellZ       (phosFitter.fCellZ),
  fCaloFlag    (phosFitter.fCaloFlag),
  fNBunches    (phosFitter.fNBunches),
  fPedSubtract (phosFitter.fPedSubtract),
  fEnergy      (phosFitter.fEnergy),
  fTime        (phosFitter.fTime),
  fQuality     (phosFitter.fQuality),
  fPedestalRMS (phosFitter.fPedestalRMS),
  fAmpOffset   (phosFitter.fAmpOffset),
  fAmpThreshold(phosFitter.fAmpThreshold),
  fOverflow    (phosFitter.fOverflow),
  fCalibData   (phosFitter.fCalibData)
{
  //Copy constructor
}

//-----------------------------------------------------------------------------
AliPHOSRawFitterv0& AliPHOSRawFitterv0::operator = (const AliPHOSRawFitterv0 &phosFitter)
{
  //Assignment operator.

  if(this != &phosFitter) {
    fModule       = phosFitter.fModule;
    fCellX        = phosFitter.fCellX;
    fCellZ        = phosFitter.fCellZ;
    fCaloFlag     = phosFitter.fCaloFlag;
    fNBunches     = phosFitter.fNBunches;
    fPedSubtract  = phosFitter.fPedSubtract;
    fEnergy       = phosFitter.fEnergy;
    fTime         = phosFitter.fTime;
    fQuality      = phosFitter.fQuality;
    fPedestalRMS  = phosFitter.fPedestalRMS;
    fAmpOffset    = phosFitter.fAmpOffset;
    fAmpThreshold = phosFitter.fAmpThreshold;
    fOverflow     = phosFitter.fOverflow;
    fCalibData    = phosFitter.fCalibData;
  }

  return *this;
}

//-----------------------------------------------------------------------------

void AliPHOSRawFitterv0::SetChannelGeo(const Int_t module, const Int_t cellX,
				     const Int_t cellZ,  const Int_t caloFlag)
{
  // Set geometry address of the channel
  // (for a case if fitting parameters are different for different channels)
  
  fModule   = module;
  fCellX    = cellX;
  fCellZ    = cellZ;
  fCaloFlag = caloFlag;
}
//-----------------------------------------------------------------------------

Bool_t AliPHOSRawFitterv0::Eval(const UShort_t *signal, Int_t /*sigStart*/, Int_t sigLength)
{
  // Calculate signal parameters (energy, time, quality) from array of samples
  // Energy is a maximum sample minus pedestal 9
  // Time is the first time bin
  // Signal overflows is there are at least 3 samples of the same amplitude above 900

  fEnergy  = 0;
  if (fNBunches > 1) {
    fQuality = 1000;
    return kTRUE;
  }
  
  const Float_t kBaseLine   = 1.0;
  const Int_t   kPreSamples = 10;

  Float_t  pedMean   = 0;
  Float_t  pedRMS    = 0;
  Int_t    nPed      = 0;
  UShort_t maxSample = 0;
  Int_t    nMax      = 0;

  for (Int_t i=0; i<sigLength; i++) {
    if (i<kPreSamples) {
      nPed++;
      pedMean += signal[i];
      pedRMS  += signal[i]*signal[i] ;
    }
    if(signal[i] >  maxSample) maxSample = signal[i];
    if(signal[i] == maxSample) nMax++;

    if(fPedSubtract) {
      if( (signal[i]-(Float_t)(pedMean/nPed)) >kBaseLine ) fTime = (Double_t)i;
    }
    else //ZS
      if( (signal[i]-(Float_t)fAmpOffset    ) >kBaseLine ) fTime = (Double_t)i;
  }
//   fTime += sigStart;
  
  fEnergy = (Double_t)maxSample;
  if (maxSample > 900 && nMax > 2) fOverflow = kTRUE;

  if (fPedSubtract) {
    if (nPed > 0) {
      fPedestalRMS=(pedRMS - pedMean*pedMean/nPed)/nPed ;
      if(fPedestalRMS > 0.) 
	fPedestalRMS = TMath::Sqrt(fPedestalRMS) ;
      fEnergy -= (Double_t)(pedMean/nPed); // pedestal subtraction
    }
    else
      return kFALSE;
  }
  else {
    //take pedestals from DB
    Double_t pedestal = (Double_t) fAmpOffset ;
    if (fCalibData) {
      Float_t truePed       = fCalibData->GetADCpedestalEmc(fModule, fCellZ, fCellX) ;
      Int_t   altroSettings = fCalibData->GetAltroOffsetEmc(fModule, fCellZ, fCellX) ;
      pedestal += truePed - altroSettings ;
    }
    else{
      AliWarning(Form("Can not read data from OCDB")) ;
    }
    fEnergy-=pedestal ;
  }
  if (fEnergy < kBaseLine) fEnergy = 0;
  
  return kTRUE;

}