#include <iostream>
#include <cmath>
#include "TCanvas.h"
#include "RooConstVar.h"
#include "RooEffProd.h"
#include "RooBreitWigner.h"
#include "RooNumIntConfig.h"
#include "RooGaussian.h"
#include "RooRealVar.h"
#include "RooFFTConvPdf.h"
#include "RooAddPdf.h"
#include "RooDataSet.h"
#include "RooPlot.h"
using namespace std;


int main()
{

    double lowrange = -100;
    double highrange = 100;

    double narrowresolution = 3.7;
    double wideresolution = 40.2;

    RooRealVar dimuon_mass("Bplus_fitted_dimuon_M","m(#mu#mu)",lowrange,highrange);


    dimuon_mass.setBins(4e4,"cache");

    RooRealVar narrow_res("narrow_res","narrow_res",narrowresolution,3,10);
    RooRealVar wide_res("wide_res","wide_res",wideresolution,20,100);

    RooGaussian narrow_resolution("narrow_resolution","narrow_resolution",dimuon_mass,RooFit::RooConst(0),RooFit::RooConst(narrowresolution));
    RooGaussian wide_resolution("wide_resolution","wide_resolution",dimuon_mass,RooFit::RooConst(0),RooFit::RooConst(wideresolution));
    RooRealVar resfrac("resfrac_low","resfrac_low",0.8,0.000,1.0);
    RooAddPdf resolution("resolution","resolution",narrow_resolution,wide_resolution,resfrac);


    RooRealVar jpsi_mean("jpsi_mean","jpsi_mean",0.0,lowrange,highrange);
    RooRealVar jpsi_width("jpsi_width","jpsi_width",0.09,0.01,0.2);


    RooBreitWigner physicspdf("physicspdf","physicspdf",dimuon_mass,jpsi_mean,jpsi_width) ;
    RooFFTConvPdf pdf("pdf","pdf",dimuon_mass,physicspdf,resolution);

    RooDataSet* gendata = pdf.generate(RooArgSet(dimuon_mass),1.1e5);

    //resfrac.setVal(0.25);

    RooPlot* polyplot = dimuon_mass.frame();
    gendata->plotOn(polyplot);
    resolution.plotOn(polyplot,RooFit::LineColor(kRed));
    pdf.plotOn(polyplot,RooFit::LineColor(kBlue));
    // physicspdf.plotOn(polyplot,RooFit::LineColor(kGreen-2))
    polyplot->SetName("polyfit");

    polyplot->Draw();
    gPad->SaveAs("FFT_sanity.pdf");

}