#include <iostream>
#include "RooWorkspace.h"
#include "RooDataSet.h"
#include "RooStats/ModelConfig.h"
#include "TFile.h"
#include "TCanvas.h"
#include "RooRealVar.h"
#include "RooDataSet.h"
#include "RooStats/ProfileLikelihoodCalculator.h"
#include "RooPlot.h"
#include "RooStats/LikelihoodInterval.h"
#include "RooStats/LikelihoodIntervalPlot.h"
#include "RooStats/SequentialProposal.h"
#include "RooStats/MCMCIntervalPlot.h"
#include "RooStats/MCMCCalculator.h"
#include "RooGenericPdf.h"
#include "RooHistPdf.h"
#include "RooProdPdf.h"
#include "RooDataHist.h"
#include "RooExtendPdf.h"
#include "TIterator.h"
#include <string>
#include "TH1F.h"
#include <sstream>


using namespace std;
using namespace RooStats;
using namespace RooFit;


template <class T>
T AddH(T A, T B, double a=1, double b=1)
{
    A = a*A;
    B = b*B;
    
    int size = A.GetSize()-2;
    double low = A.GetBinLowEdge(1);
    double high= A.GetBinLowEdge(size+1);
    
    std::string name = string( A.GetName() )+string( B.GetName() );
    T C(name.c_str(),"",size,low,high);
    
    for(int bin=1;bin<=size;bin++) C.SetBinContent(bin, A.GetBinContent(bin)+B.GetBinContent(bin) );
    
    return C;
}

std::string character(int i)
{
    std::stringstream s;
    s << i;
    
    return s.str();
}


TH1F Interpolate(double x)
{
    int low = (int)x;
    double z= x-low;
    
    TFile *ifile = new TFile("histograms.root","read");
    
    string file_1 = string("h_")+character(low);
    string file_2 = string("h_")+character(low+1);
    
    TH1F *h1=(TH1F*)ifile->Get(file_1.c_str() );
    TH1F *h2=(TH1F*)ifile->Get(file_2.c_str() );
    
    TH1F h3=AddH<TH1F>( *h1, *h2,1-z,z );
    
    return h3;
}

void code(double z)
{
    RooRealVar x ("x" ,"",-2,2);
    
    TH1F h_obj=Interpolate(z);
    
    TH1F *sign = &h_obj;
    
    RooDataHist *sig_n = new RooDataHist("signal_n","",RooArgSet(x),sign);
    RooHistPdf *sig = new RooHistPdf("sig_pdf","",RooArgSet(x),*sig_n);
    
    RooPlot *plot = x.frame();
    sig->plotOn(plot);
    
    plot->Draw();
}