/* ======================================================================== *\
!
! *
! * This file is part of MARS, the MAGIC Analysis and Reconstruction
! * Software. It is distributed to you in the hope that it can be a useful
! * and timesaving tool in analysing Data of imaging Cerenkov telescopes.
! * It is distributed WITHOUT ANY WARRANTY.
! *
! * Permission to use, copy, modify and distribute this software and its
! * documentation for any purpose is hereby granted without fee,
! * provided that the above copyright notice appear in all copies and
! * that both that copyright notice and this permission notice appear
! * in supporting documentation. It is provided "as is" without express
! * or implied warranty.
! *
!
!
!   Author(s): Josep Flix 04/2001 <mailto:jflix@ifae.es>
!   Author(s): Thomas Bretz 05/2001 <mailto:tbretz@uni-sw.gwdg.de>
!   Author(s): Sebastian Commichau 12/2003 
!   Author(s): Javier Rico 01/2004 
!
!   Copyright: MAGIC Software Development, 2000-2004
!
!
\* ======================================================================== */

/////////////////////////////////////////////////////////////////////////////
//                                                                         //
//   MPedCalcPedRun                                                        //
//                                                                         //
//  This task takes a pedestal run file and fills MPedestalCam during      //
//  the Process() with the pedestal and rms computed in an event basis.    //
//  In the PostProcess() MPedestalCam is finally filled with the pedestal  //
//  mean and rms computed in a run basis.                                  //
//  More than one run (file) can be merged                                 //
//                                                                         //
//  Input Containers:                                                      //
//   MRawEvtData                                                           //
//                                                                         //
//  Output Containers:                                                     //
//   MPedestalCam                                                          //
//                                                                         //
//                                                                         //
/////////////////////////////////////////////////////////////////////////////

#include "MPedCalcPedRun.h"

#include "MParList.h"

#include "MLog.h"
#include "MLogManip.h"

#include "MRawRunHeader.h"  
#include "MRawEvtPixelIter.h"
#include "MRawEvtData.h"

#include "MPedestalPix.h"
#include "MPedestalCam.h"

#include "MGeomCamMagic.h"

ClassImp(MPedCalcPedRun);

using namespace std;

MPedCalcPedRun::MPedCalcPedRun(const char *name, const char *title)
{
    fName  = name  ? name  : "MPedCalcPedRun";
    fTitle = title ? title : "Task to calculate pedestals from pedestal runs raw data";

    AddToBranchList("fHiGainPixId");
    AddToBranchList("fHiGainFadcSamples");
}

Int_t MPedCalcPedRun::PreProcess( MParList *pList )
{
    fRawEvt = (MRawEvtData*)pList->FindObject("MRawEvtData");
    if (!fRawEvt)
    {
        *fLog << err << "MRawEvtData not found... aborting." << endl;
        return kFALSE;
    }

    fPedestals = (MPedestalCam*)pList->FindCreateObj("MPedestalCam");
    if (!fPedestals)
        return kFALSE;

    fNumSamplesTot=0;

    return kTRUE;
}

Bool_t MPedCalcPedRun::ReInit(MParList *pList)
{
    const MRawRunHeader *runheader = (MRawRunHeader*)pList->FindObject("MRawRunHeader");
    if (!runheader)
    {
        *fLog << warn << dbginf;
        *fLog << "Warning - cannot check file type, MRawRunHeader not found." << endl;
    }
    else
        if (runheader->GetRunType() == kRTMonteCarlo)
            return kTRUE;

    fNumPixels = fPedestals->GetSize();

    if(fSumx.GetSize()==0)
      {
	fSumx.Set(fNumPixels);
	fSumx2.Set(fNumPixels);

	memset(fSumx.GetArray(),  0, sizeof(Float_t)*fNumPixels);
	memset(fSumx2.GetArray(), 0, sizeof(Float_t)*fNumPixels);
      }

    // Calculate an even number for the hi gain samples to avoid
    // biases due to the fluctuation in pedestal from one slice to
    // the other one
    fNumHiGainSamples = runheader->GetNumSamplesHiGain() & ~1;

    return kTRUE;
}

Int_t MPedCalcPedRun::Process()
{
    MRawEvtPixelIter pixel(fRawEvt);

    while (pixel.Next())
    {
              Byte_t *ptr = pixel.GetHiGainSamples();
        const Byte_t *end = ptr + fNumHiGainSamples;

	UInt_t sum = 0;
	UInt_t sqr = 0;
	
	do
	  {
	    sum += *ptr;
	    sqr += *ptr * *ptr;
	  }
	while (++ptr != end);
	
	const Float_t msum = (Float_t)sum;
	const Float_t msqr = (Float_t)sqr;
	
	const Float_t higainped = msum/fNumHiGainSamples;
	const Float_t higainrms = TMath::Sqrt((msqr-msum*msum/fNumHiGainSamples)/(fNumHiGainSamples-1.));
	
	const UInt_t idx = pixel.GetPixelId();
	(*fPedestals)[idx].Set(higainped, higainrms);
	
	fSumx[idx]  += msum;
	fSumx2[idx] += sqr;
    }
    
    fPedestals->SetReadyToSave();
    fNumSamplesTot+=fNumHiGainSamples;
    
    return kTRUE;
}

Int_t MPedCalcPedRun::PostProcess()
{
  // Compute pedestals and rms from the whole run
  const Int_t n  = fNumSamplesTot;
  
  MRawEvtPixelIter pixel(fRawEvt);
  
  while (pixel.Next())
    {
      const UInt_t pixid = pixel.GetPixelId();
      
      const Float_t sum  = fSumx.At(pixid);
      const Float_t sum2 = fSumx2.At(pixid);
      
      const Float_t higainped = sum/n;
      const Float_t higainrms = TMath::Sqrt((sum2-sum*sum/n)/(n-1.));
      
      (*fPedestals)[pixid].Set(higainped, higainrms);
    }
  
  return kTRUE;
}