/***********************************************************************
**                                                                    **
**          /----------------------------------------------\          **
**         |  Delphes, a framework for the fast simulation  |         **
**         |       of a  generic collider experiment        |         **
**          \-------------  arXiv:0903.2225v1  ------------/          **
**                                                                    **
**                                                                    **
**   This package uses:                                               **
**   ------------------                                               **
**   ROOT: Nucl. Inst. & Meth. in Phys. Res. A389 (1997) 81-86        **
**   FastJet algorithm: Phys. Lett. B641 (2006) [hep-ph/0512210]      **
**   Hector: JINST 2:P09005 (2007) [physics.acc-ph:0707.1198v2]       **
**   FROG: [hep-ex/0901.2718v1]                                       **
**   HepMC: Comput. Phys. Commun.134 (2001) 41                        **
**                                                                    **
** ------------------------------------------------------------------ **
**                                                                    **
**   Main authors:                                                    **
**   -------------                                                    **
**                                                                    **
**                Severine Ovyn                Xavier Rouby           **
**          severine.ovyn@uclouvain.be      xavier.rouby@cern         **
**                                                                    **
**         Center for Particle Physics and Phenomenology (CP3)        **
**                Universite catholique de Louvain (UCL)              **
**                     Louvain-la-Neuve, Belgium                      **
**                                                                    **
**                      Copyright (C) 2008-2009,                      **
**                        All rights reserved.                        **
**                                                                    **
***********************************************************************/

#include <iostream>
#include <fstream>
#include <iomanip>
#include <cmath>
#include "TChain.h"
#include "TFile.h"
#include "DelphesRootConverter.h"
using namespace std;

DelphesRootConverter::DelphesRootConverter(const string& inputFileList, const string& outputFileName, const int& Nevents)
{
  
  // Open a stream connected to an event file:
  ifstream infile(inputFileList.c_str());
  string filename;
  if(!infile.is_open()) {
     cerr << left  << setw(30) <<"**   ERROR: Can't open     "<<""
          << left  << setw(20) << inputFileList                        <<""
          << right << setw(19) <<"for input **"<<""<<endl;
     exit(1);
  }
 
  TChain chainGEN("GEN");
  while(1)
    {
      infile >> filename;
      if(!infile.good()) break;
      ifstream checking_the_file(filename.c_str());
      if(!checking_the_file.good()) 
	{ 
	  cerr << left  << setw(30) <<"**   ERROR: Can't find file  "<<""
	       << left  << setw(36) << filename                      <<""
	       << right << setw(3) <<" **"<<""<<endl;
	  continue;
	}
      else checking_the_file.close();

      chainGEN.Add(filename.c_str());
    }

    TFile * newFile = TFile::Open(outputFileName.c_str(),"RECREATE");
    newFile->cd();
    TTree * copiedChain;
    int nevents = min(Nevents,(int)chainGEN.GetEntries());
    if(nevents<0) copiedChain = chainGEN.CopyTree("");   // copy the whole chain
    else copiedChain = chainGEN.CopyTree("","",nevents); // copy a smaller part of the chain
    copiedChain->Write();
    newFile->Close();

}