#ifndef __CINT__
#include "RooGlobalFunc.h"
#endif

#include <iostream> 
#include <fstream> 
#include <string> 
#include <algorithm> 
#include <vector> 
#include <iomanip> 
#include <cmath> 

//#include <cstdlib>
#include "RooFit.h"// 
#include "RooRealVar.h"
#include "RooAbsPdf.h"
#include "RooAddPdf.h" 
#include "RooDataSet.h" 
#include "RooDataHist.h" 
#include "RooGaussian.h"
#include "RooGlobalFunc.h"
#include "RooBifurGauss.h"
#include "RooLandau.h"
#include "RooChebychev.h"
#include "RooFitResult.h"
#include "RooNLLVar.h"
#include "RooMinuit.h"
#include "RooPlot.h"
#include "RooArgList.h"
#include "RooHist.h"
//#include "RooDstarBG.h"     // for the threshold function
#include "TLine.h"
#include "TFile.h"
#include "TCanvas.h"
#include "TTree.h"
#include "TH1.h"
#include "TH1F.h"
#include "TRandom.h"
#include "TString.h"
#include "TApplication.h"
#include "TROOT.h"
#include "TPad.h" 
//#include "RooFitModels.h"
#include "RooDstD0BG.h"  // will be used for fitting deltam of combinatoric background 

using namespace RooFit ; 
using namespace std ;

int combinatoric_mdz()
{
	
	//--------------------BLock1-------------------------------//
	// declare the required variables for fitting //

	RooRealVar M_dz("M_dz","M_{D^{0}}(GeV/c^{2})",1.81,1.92); // for Mdz variable
	RooRealVar deltam("deltam","#Delta M(GeV/c^{2})",0.14,0.15); // fro deltam variable
	

        RooDataSet* ds1 = (RooDataSet*)RooDataSet::read("signal_new.txt",RooArgSet(M_dz, deltam),"Q");
        ds1->Print("V");

		RooPlot* frame = M_dz.frame(Title("M_{D^{0}}"));// making a frame linking to variable mdz
		ds1->plotOn(frame);// plotting all the data on the frame
	
	
	
	
		//----------------------BLOCK 4------------------------// ********( !!!! very important part)
		//--------here start constructing the models to be used for fitting -----------//


		//-------------------Chebychev polynomial----------------------//
		RooRealVar a1("a1","a1",1,0,10);
		RooRealVar a2("a2","a2",0.5,-1,1);
		RooChebychev dg_mdz1("dg_mdz1","dg_mdz1",M_dz,RooArgList(a1,a2));
	
		
		unsigned long nentries = (long)ds1->numEntries();
		RooRealVar nsig("nsig","nsig",nentries*1,0,nentries*1.2);
		RooAddPdf dg_mdz("dz_mdz","dg_mdz",RooArgList(dg_mdz1),RooArgList(nsig));  // this is done to float the yield 






	dg_mdz.fitTo(*ds1,Extended(kTRUE),Minos(1));//,Extended(kTRUE));//,Extended(),Minos(1));
	dg_mdz.plotOn(frame,Name("Total pdf"),LineColor(kBlue));
	dg_mdz.paramOn(frame);
	
		
	

	double chi2_ndf =  frame->chiSquare();//
	cout<<"chi square = "<<chi2_ndf<<endl<<endl<<endl<<endl<<endl;
	TPaveText *box= new TPaveText(0.3, 0.85, 0.6, 0.9,"BRNDC");
	box->SetFillColor(10);
	box->SetBorderSize(1);
	box->SetTextAlign(12);
	box->SetTextSize(0.04F);
	box->SetFillStyle(1001);
	box->SetFillColor(10);
	TText *text = 0;
	Char_t buf[30];
	sprintf( buf,  "#chi^{2}/ndf = %f", chi2_ndf );
	text = box->AddText( buf );
	frame->addObject(box) ; 
	
	/////////////pull distribution////////////////
		
//*********** pull ******************************* 
	RooPlot* z1frame = M_dz.frame(Title("Pull Distribution"));
	RooHist* hpull1 = frame->pullHist();
	z1frame->addPlotable(hpull1,"P");// p is drawing option.

	TCanvas* c1 = new TCanvas("c1","c1",550,400) ;
	c1->Divide(1,2) ; // column, row
	double xmin = 1.81; 
	double xmax = 1.92;
	TLine *line = new TLine(xmin,0.0,xmax,0.0);
	
	TLine *line1 = new TLine(xmin,3.0,xmax,3.0);
	TLine *line2 = new TLine(xmin,-3.0,xmax,-3.0);
 
	c1->cd(2)->SetPad(0.005,0.005,0.995,0.2525); line->SetLineColor(kRed); line->SetLineWidth(2); 
	//gPad->SetLeftMargin(0.15); 
	//z1frame->GetYaxis()->SetTitleOffset(1.45); 
	z1frame->GetYaxis()->SetTitle("Pull(#sigma)"); 
	z1frame->GetXaxis()->CenterTitle();
	z1frame->Draw();
	line1->SetLineColor(kRed); line1->SetLineWidth(3); line1->SetLineStyle(2);
	line2->SetLineColor(kRed); line2->SetLineWidth(3); line2->SetLineStyle(2);
	line->Draw("SAME"); //z1frame->GetYaxis()->SetRangeUser(-3.5, 3.5);
	line1->Draw("SAME"); 
	line2->Draw("SAME");
	c1->cd(1)->SetPad(0.005,0.2525,0.995,0.995); //gPad->SetLeftMargin(0.15); 
	//frame->GetYaxis()->SetTitleOffset(1.45);
	
	
	frame->GetXaxis()->CenterTitle();
	// Add the components pdf's after calculating the chi square and pull.
	dg_mdz.plotOn(frame);//,Name("Asymmetric Gauss1"),Components(gauss1),LineStyle(kDashed),LineColor(kRed));

	frame->Draw();
	
	TLegend *leg = new TLegend(0.5,0.5,0.6,0.6);
	leg->AddEntry("dg_mdz1","Chebychev polynomial","L");
	leg->Draw();
	
		
	c1->Draw();
	
   cout<<"the total no. of events are "<<nentries<<endl;
   

   return 1;
}