#include "RooWorkspace.h"
#include "RooAbsPdf.h"
#include "RooRealVar.h"
#include "RooPlot.h"
#include "RooDataSet.h"
#include "RooFitResult.h"

#include "TFile.h"


// roofit tutorial showing how to fit whatever model we get from a file 

// we assume the name of the workspace is w
// the name of the pdf is pdf 
// the name of the data is data
const char * workspaceName = "w"; 
const char * pdfName = "pdf"; 
const char * dataName = "data"; 


using namespace RooFit;



void fitModel() { 

   // read file: 
   // following lines are for reading workspace
   // and to check that is fine 
  TFile *file = TFile::Open("260.root");
   
   RooWorkspace* w = (RooWorkspace*) file->Get("combined");
   w->Print();

   // change the mass in the workspace
   float lowMass = 400.0; 

   RooRealVar* twoTagMass = (RooRealVar*)w->var("mX_2tag");
   twoTagMass->setConstant(false);
   twoTagMass->setRange(0,10000);
   twoTagMass->setVal(lowMass);

   w->import(*twoTagMass, RenameVariable("mX_2tag", "new_mX_2tag"));
   w->factory("EDIT::mX_2tag(mX_2tag, mX_2tag=new_mX_2tag)");

   
   RooRealVar* oneTagMass = (RooRealVar*)w->var("mX_1tag");
   oneTagMass->setConstant(false);
   oneTagMass->setRange(0,10000);
   oneTagMass->setVal(lowMass);

   w->import(*oneTagMass, RenameVariable("mX_1tag", "new_mX_1tag"));
   w->factory("EDIT::mX_1tag(mX_1tag, mX_1tag=new_mX_1tag)");


   std::string varAsString = "400";

   TString partA(varAsString);
   TString partB("_lowMass_debug.root");
   TString totalC = partA + partB;

   w->writeToFile(totalC);


}