/** @file CbmBuildEventsSimple.cxx
 ** @author //Dr.Sys <Mikhail.Prokudin@cern.ch>
 ** @date 07.12.2016
 **/

#include "CbmBuildEventsSimple.h"

#include "TClonesArray.h"
#include "TStopwatch.h"

#include "FairLogger.h"
#include "FairRootManager.h"

#include "CbmEvent.h"
#include "CbmLink.h"
#include "CbmMatch.h"
#include "CbmStsDigi.h"
#include "CbmStsAddress.h"

#include <cassert>
#include <iomanip>
#include <iostream>
#include <map>

using namespace std;


// =====   Constructor   =====================================================
CbmBuildEventsSimple::CbmBuildEventsSimple() :
  FairTask("BuildEventsSimple"), fStsDigis(NULL), fEvents(NULL),
    fSliceN(0), fEv(0), fNDigis(0),   
    fSN(-1111), fST(-1111), fNStsDigis(),
    fWindDur(5), fMinusDeltaT(10), fPlusDeltaT(15), fDeadT(10),
    fMinHitStations(8), fMinDigis(2000)

{
  ;
}
// ===========================================================================



// =====   Destructor   ======================================================
CbmBuildEventsSimple::~CbmBuildEventsSimple()
{
  ;
}
// ===========================================================================


// =====   FillEvent method   ================================================
void CbmBuildEventsSimple::FillEvent(Int_t st, Int_t end)
{
  Int_t i;
//  CbmStsDigi* digi;
  Int_t nev=fEvents->GetEntriesFast();
  CbmEvent* event=new ((*fEvents)[nev]) CbmEvent(fEv++);

  for(i=st;i<=end;i++)
  {
//    digi=(CbmStsDigi*)fStsDigis->At(i);
    event->AddData(kStsDigi, i);
  }
  FairRootManager::Instance()->Fill();
  LOG(info) << "CbmBuildEventsSimple:	Event constructed. Digis used from " << st << " to " << end << ".";
}

// ===========================================================================

// =====   Task execution   ==================================================
void CbmBuildEventsSimple::Exec(Option_t*)
{

  // Reset output array
  fEvents->Delete();

  Int_t i=0;
  Int_t j=0;
//  Int_t n=0;
  Int_t k;
  Int_t nsts=fStsDigis->GetEntriesFast();
  Double_t t;
  CbmStsDigi* digi;
  CbmStsDigi* digi2;
  Int_t n0;
  Int_t n1;

  LOG(info) << "CbmBuildEventsSimple:	Sts digis in slice " << nsts;
  fNDigis=0;
  for(i=0;i<16;i++) fNStsDigis[i]=0;
  fSN=0;
  fST=-1111;
  
  for(i=0;i<nsts;i++)
  {
    digi=(CbmStsDigi*)fStsDigis->At(i);
    if (digi==NULL) continue;
    t=digi->GetTime();
    fNDigis++;
    k=CbmStsAddress::GetElementId(digi->GetAddress(), kStsUnit);
    fNStsDigis[k]++;
    if (fST==-1111) { fSN=i; fST=t; }
    if (t-fST>fWindDur)
    {
      for(j=fSN;j<i;j++)
      {
        digi2=(CbmStsDigi*)fStsDigis->At(j); 
        if (digi2==NULL) continue;
	fST=digi2->GetTime();
        if (t-fST<=fWindDur) { fSN=j; break; }
	fNDigis--;
        k=CbmStsAddress::GetElementId(digi2->GetAddress(), kStsUnit);
        fNStsDigis[k]--;
      }
      if (j==i) { fSN=i; fST=t; }
    } 

    if (fNDigis>=fMinDigis)
    {
      k=0;
      for(j=0;j<16;j++)
	if (fNStsDigis[j]>0) k++;
      if (k>=fMinHitStations)
      {
	// Reached required number of digis and hit stations
        for(j=i;j>-1;j--)
	{
          digi2=(CbmStsDigi*)fStsDigis->At(j); 
          if (digi2==NULL) continue;
	  if (fST-digi2->GetTime()>fMinusDeltaT) break;
	}
	n0=j+1;
	for(j=i+1;j<nsts;j++)
	{
          digi2=(CbmStsDigi*)fStsDigis->At(j); 
          if (digi2==NULL) continue;
	  if (digi2->GetTime()-t>fPlusDeltaT) break;
	}
	n1=j-1;
	FillEvent(n0, n1);
	if (j==nsts)
	{
	  //Reached the end of the slice
	  i=j; break;
	}
	for(j=n1+1;j<nsts;j++)
	{
          digi2=(CbmStsDigi*)fStsDigis->At(j); 
          if (digi2==NULL) continue;
	  if (digi2->GetTime()-t>fPlusDeltaT+fDeadT) break;
	}
	if (j==nsts)
	{
	  //Reached the end of the slice
	  i=j; break;
	}
	i=j-1;
	for(j=0;j<16;j++) fNStsDigis[j]=0;
	fNDigis=0; fSN=i+1; 
	digi2=(CbmStsDigi*)fStsDigis->At(i+1);
	fST=digi2->GetTime();
/*	
	cout << "--> ";
        digi2=(CbmStsDigi*)fSlice->GetData(kSTS, n0);
	cout << n0 << "(" << digi2->GetTime() << ")" << ", ";
        digi2=(CbmStsDigi*)fSlice->GetData(kSTS, n1);
	cout << n1 << "(" << digi2->GetTime() << ")" << ": ";
        digi2=(CbmStsDigi*)fSlice->GetData(kSTS, i);
	cout << i << "(" << digi2->GetTime() << ")" << endl;
*/	
      }

    }
//    cout << t << " " << fST << " " << fNDigis << " :";
//    for(k=0;k<8;k++) cout << " " << fNStsDigis[k];
//    cout <<  endl;
  }
  fSliceN++;
}
// ===========================================================================



// =====   Task initialisation   =============================================
InitStatus CbmBuildEventsSimple::Init()
{
  // --- Get FairRootManager instance
  FairRootManager* ioman = FairRootManager::Instance();
  assert ( ioman );

  // --- Get input array (CbmStsDigi)
  fStsDigis = (TClonesArray*) ioman->GetObject("StsDigi");
  assert ( fStsDigis );

  // Register output array (CbmStsDigi)
  fEvents = new TClonesArray("CbmEvent",100);
  ioman->Register("Event", "CbmEvent", fEvents, IsOutputBranchPersistent("Event"));

  return kSUCCESS;
}
// ===========================================================================


ClassImp(CbmBuildEventsSimple)