#include <TMath.h>
using namespace RooFit;

double CheckInt(double integral, double fwhm){
  double max = integral/(TMath::Sqrt(2*TMath::Pi())*fwhm);
  return max;
}

void Fit(){
  //File Import
  TFile *f = new TFile("Forum.root");
  TTree *t = (TTree*)f->Get("Data");

  double fwhm = 5/(2*TMath::Sqrt(2*TMath::Log(2)));

  //RooFit Definitions
  //Signal
  RooRealVar En("Energy","Energy",536.1-50,536.1+50);
  RooRealVar mean("mean","mean",536.1);
  RooRealVar sigma("sigma","sigma",fwhm);
  RooGaussian gss("gss","gss",En,mean,sigma);
  RooRealVar yield("yield","yield",0,0,100000);
  //Background

  //Range of this is different
  RooRealVar poly_c1("c1","c1",0,0,10);
  RooRealVar poly_c2("c2","c2",0,0,10);
  
  RooBernstein background("background","background",En,RooArgList(poly_c1,poly_c2));
  RooRealVar bkgy("bkgy","yield background",50,0,100000);
  //Setup Model
  RooAddPdf model("model","Total PDF",RooArgList(gss,background),RooArgList(yield,bkgy));
  //Import data
  RooDataSet data("data","data",RooArgSet(En),Import(*t),Cut(Form("%e < Energy && Energy < %e",536.1-50,536.1+50)));
  //Fit
  model.fitTo(data,Extended(),Verbose(false));

  //RooPlot
  RooPlot *P = En.frame(Bins(100),Range(536.1-50,536.1+50));
  data.plotOn(P);
  model.plotOn(P,LineColor(kBlue));
  model.plotOn(P,Components(background),LineColor(kRed));

  Double_t chi = P->chiSquare();
  En.setVal(536.1);
  Double_t max = model.getVal(RooArgSet(En))*data.sumEntries();

  //Cosmetic
  TLatex lax;
  lax.SetNDC();
  lax.SetTextAlign(22);
  TText *intL = new TText();
  intL->SetNDC();
  intL->SetText(.5,.03,Form("Integral: %f",yield.getVal()));
  intL->SetTextAlign(22);
  intL->SetTextSize(0.03);
  intL->SetTextColor(kBlue);
  TText *cLab = new TText();
  cLab->SetNDC();
  cLab->SetText(.9,.95,Form("Chi2: %f",chi));
  cLab->SetTextAlign(32);
  cLab->SetTextSize(0.03);
  cLab->SetTextColor(kRed);
  TText *mLab = new TText();
  mLab->SetNDC();
  mLab->SetText(.1,.02,Form("Max: %f:",max));
  mLab->SetTextAlign(12);
  mLab->SetTextSize(0.03);
  mLab->SetTextColor(kRed);
  TText *mLab1 = new TText();
  mLab1->SetNDC();
  mLab1->SetText(.1,.05,Form("Th. Max: %f",CheckInt(yield.getVal(),fwhm)));
  mLab1->SetTextAlign(12);
  mLab1->SetTextSize(0.03);
  mLab1->SetTextColor(kRed);
    
  P->addObject(intL);
  P->addObject(cLab);
  P->addObject(mLab);
  P->addObject(mLab1);
  
  P->SetTitle(" ");
  P->Draw();
  lax.DrawLatex(0.5,0.95,"Cut #beta#beta + #gamma_{1} Fit #gamma_{2} M2");
  cout << "Signal Yield: " << yield.getVal() << " +/- " << yield.getError() << endl;
  cout << "C1: " << poly_c1.getVal() <<  " +/- " << poly_c1.getError() << endl;
  cout << "C2: " << poly_c2.getVal() << " +/- " << poly_c2.getError() << endl;
  cout << "Bkg. Yield: " << bkgy.getVal() << " +/- " << bkgy.getError() <<  endl;

  En.Delete();
  mean.Delete();
  sigma.Delete();
  gss.Delete();
  yield.Delete();
  poly_c1.Delete();
  poly_c2.Delete();
  background.Delete();
  bkgy.Delete();
  model.Delete();
  data.Delete();
 

}