//void b2style_pad()

const int    belle2_font = 133;
const double belle2_tsize = 26;

void set_style()
{
  gROOT->SetStyle("Modern");
  TStyle *belle2Style = new TStyle("BelleII","Belle II style");

  // set the paper & margin sizes
  belle2Style->SetPaperSize(20,26);

  // set canvas, pads, etc.
  //belle2Style->SetCanvasDefW(600);
  //belle2Style->SetCanvasDefH(600);
  //belle2Style->SetCanvasDefW(600);
  //belle2Style->SetCanvasDefH(600);

  //belle2Style->SetFillColor(1);
  //belle2Style->SetFillStyle(1001);
  belle2Style->SetFrameFillColor(0);
  belle2Style->SetFrameBorderMode(0);
  belle2Style->SetPadBorderMode(0);
  belle2Style->SetPadColor(0);
  belle2Style->SetCanvasBorderMode(0);
  belle2Style->SetCanvasColor(0);
  belle2Style->SetStatColor(0);
  belle2Style->SetLegendBorderSize(0);

   // set margin sizes
  belle2Style->SetPadTopMargin(0.05);
  belle2Style->SetPadRightMargin(0.05);
  belle2Style->SetPadBottomMargin(0.16);
  belle2Style->SetPadLeftMargin(0.16);

  // use large fonts
  belle2Style->SetTextFont(belle2_font);
  belle2Style->SetTextSize(belle2_tsize);

  belle2Style->SetLabelFont(belle2_font,"x");
  belle2Style->SetTitleFont(belle2_font,"x");
  belle2Style->SetLabelFont(belle2_font,"y");
  belle2Style->SetTitleFont(belle2_font,"y");
  belle2Style->SetLabelFont(belle2_font,"z");
  belle2Style->SetTitleFont(belle2_font,"z");

  belle2Style->SetLabelSize(belle2_tsize,"x");
  belle2Style->SetLabelSize(belle2_tsize,"y");
  belle2Style->SetLabelSize(belle2_tsize,"z");
  belle2Style->SetTitleSize(belle2_tsize,"x");
  belle2Style->SetTitleSize(belle2_tsize,"y");
  belle2Style->SetTitleSize(belle2_tsize,"z");

  belle2Style->SetTitleOffset(1.5,"x");
  belle2Style->SetTitleOffset(1.5,"y");
  belle2Style->SetTitleOffset(1.5,"z");

  belle2Style->SetLabelOffset(0.01,"x");
  belle2Style->SetLabelOffset(0.01,"y");
  belle2Style->SetLabelOffset(0.01,"z");

  belle2Style->SetLegendFont(belle2_font);

  // use bold lines and markers
  belle2Style->SetMarkerStyle(20);
  belle2Style->SetMarkerSize(1.0);
  belle2Style->SetHistLineWidth(2);
  belle2Style->SetFrameLineWidth(2);
  belle2Style->SetLineWidth(2);
  belle2Style->SetFuncWidth(2);
  belle2Style->SetLineStyleString(2,"[12 12]");// postscript dashes

  // get rid of X error bars
  //belle2Style->SetErrorX(0.001);
   // get rid of error bar caps
  belle2Style->SetEndErrorSize(0.);

  // do not display any of the standard histogram decorations
  belle2Style->SetOptTitle(0);
  belle2Style->SetOptStat(0);
  belle2Style->SetOptFit(0);

  // put tick marks on top and RHS of plots
  belle2Style->SetPadTickX(1);
  belle2Style->SetPadTickY(1);

  // histogram divisions: only 5 in x to avoid label overlaps
  belle2Style->SetNdivisions(505,"x");
  belle2Style->SetNdivisions(510,"y");

  // function
  belle2Style->SetFuncColor(kBlue);
  belle2Style->SetFuncStyle(0);

  // legend
  belle2Style->SetLegendBorderSize(0);
  belle2Style->SetLegendFillColor(0);

  belle2Style->SetHistMinimumZero();

  std::cout << "-------------------------" << std::endl;
  std::cout << "Set Belle II Style" << std::endl;
  std::cout << "-------------------------" << std::endl;

  gROOT->SetStyle("BelleII");
  gROOT->ForceStyle();

  TGaxis::SetMaxDigits(4);
}

TGraph *make_swapped_graph(TH1 *h1) {
   // copy all points from histogram
   TGraph *gr = new TGraph(h1);

   Int_t nbins = gr->GetN();

   Double_t x,y;

   // swap x/y coordinates
   for (int n=0;n<nbins;++n) {
      gr->GetPoint(n,x,y);
      gr->SetPoint(n,y,x);
   }

   return gr;
}

TGraph *make_swapped_graph1(TH1 *h2) {
   // copy all points from histogram
   TGraph *gr3 = new TGraph(h2);

   Int_t nbins1 = gr3->GetN();

   Double_t x1,y1;

   // swap x/y coordinates
   for (int n=0;n<nbins1;++n) {
      gr3->GetPoint(n,x1,y1);
      //gr3->SetPoint(n,y1,x1);
   }

   return gr3;
}

void DividePad(Int_t nx, Int_t ny, Float_t l, Float_t r, Float_t t, Float_t b, TPad *gpad)
{
  if(!gpad) gpad = (TPad*) gPad;
  gpad->SetTopMargin(0.);
  gpad->SetBottomMargin(0.);
  gpad->SetLeftMargin(0.);
  gpad->SetRightMargin(0.);
  
  Int_t ix, iy, n=0;
  Double_t x1, x2, y1, y2;
  Double_t dx = ((1-r)*(1-l))/((1-r)*(1-l)*(nx-2)-r+2-l);
  Double_t dl = dx/(1-l);
  Double_t dy = ((1-t)*(1-b))/((1-t)*(1-b)*(ny-2)-t+2-b);
  Double_t db = dy/(1-b);
  
  y1 = 0;
  y2 = db;
  for (iy=0; iy<ny; iy++) {
    x1 = 0;
    x2 = dl;
    for (ix=0;ix<nx;ix++) {
      if (x1 > x2) continue;
      n++;
      const char *name = Form("%s_%d",gpad->GetName(),n);
      TPad *pad = new TPad(name,name,x1,y1,x2,y2,0);
      pad->SetTopMargin(0.);
      pad->SetBottomMargin(0.);
      pad->SetLeftMargin(0.);
      pad->SetRightMargin(0.);
      if (ix==0)    pad->SetLeftMargin(l);
      if (ix==nx-1) pad->SetRightMargin(r);
      if (iy==ny-1) pad->SetTopMargin(t);
      if (iy==0)    pad->SetBottomMargin(b);
      x1 = x2;
      if (ix==nx-2) x2 = 1;
      else          x2 = x1+dx;
      pad->SetNumber(n );
      pad->Draw();
    }
    y1 = y2;
    if (iy==ny-2) y2 = 1;
    else          y2 = y1+dy;
  }
}

void b2_style_pad()

{
  
  TCanvas *c = new TCanvas("c","c",600,600);
  DividePad(2,2,0.2,0.2,0.2,0.2);
   
  // Create, fill and project a 2D histogram.
  TH2F *h1 = new TH2F("ks_fde","",100, -50,400,100,-50,400);
  TH2F *h2 = new TH2F("ks_fde_sig","",100, -50,400,100,-50,400);
  TLine *l1 = new TLine(20,0,20,1720);
  TLine *l2 = new TLine(20,0,20,1055);

  TFile *f = new TFile("for_fds_plots.root");
  TTree *tree = (TTree*)f->Get("DstD0PiKSKS");

  Double_t  KS1_flightDistance, KS1_flightDistanceErr,KS2_flightDistance, KS2_flightDistanceErr, Dst_isSignalAcceptMissingGamma, KS1_mcFlightDistance, KS2_mcFlightDistance;

  tree->SetBranchAddress("KS1_flightDistance",&KS1_flightDistance);
  tree->SetBranchAddress("KS2_flightDistance",&KS2_flightDistance);
  tree->SetBranchAddress("KS1_flightDistanceErr",&KS1_flightDistanceErr);
  tree->SetBranchAddress("KS2_flightDistanceErr",&KS2_flightDistanceErr);
  tree->SetBranchAddress("Dst_isSignalAcceptMissingGamma",&Dst_isSignalAcceptMissingGamma);
  
  Int_t nentries = (Int_t)tree->GetEntries();
  for (Int_t i=0; i<nentries; i++) {
    tree->GetEntry(i);
    h1->Fill(KS1_flightDistance/(KS1_flightDistanceErr),KS2_flightDistance/(KS2_flightDistanceErr));
    //h1->GetXaxis()->SetTitle("flight distance significance (lower momentum K^{0}_{S})");
    //h1->GetXaxis()->SetTitleSize(0.05);
    //h1->GetYaxis()->SetTitle("flight distance significance (higher momentum K^{0}_{S})");
    //h1->GetYaxis()->SetTitleSize(0.04);
    //h1->GetYaxis()->SetTitleOffset(1);
    
    if(Dst_isSignalAcceptMissingGamma==1){
      h2->Fill(KS1_flightDistance/(KS1_flightDistanceErr),KS2_flightDistance/(KS2_flightDistanceErr));
           
    }
  }
  
  TH1D * projh2X = h1->ProjectionX();
  TH1D * projh2Y = h1->ProjectionY();
  TH1D * projh2X_sig = h2->ProjectionX();
  TH1D * projh2Y_sig = h2->ProjectionY();
  
  // Drawing
  //center_pad->cd();
  c->cd(1);
  gStyle->SetPalette(1);

  h1->SetMarkerColor(kBlue);
  h1->SetMarkerStyle(20);
  h1->SetMarkerSize(0.3);
  h1->Draw();
  h2->SetMarkerColor(kRed);
  h2->SetMarkerStyle(20);
  h2->SetMarkerSize(1);
  h2->Draw("same");

  
  /*top_pad->cd();
  projh2X->SetLineColor(kBlue);
  projh2X->SetLineWidth(2);
  projh2X->Draw("");
  projh2X_sig->Scale(50);
  projh2X_sig->SetLineColor(kRed);
  projh2X_sig->SetLineWidth(2);
  projh2X_sig->Draw("same");
  l1->Draw("same");
  l1->SetLineWidth(2);
  l1->SetLineStyle(2);*/

  c->cd(3);
  projh2X->SetLineColor(kBlue);
  projh2X->SetFillStyle(0);
  projh2X->SetLineStyle(1);
  projh2X->SetLineWidth(2);

  // projh2Y->Draw("hbar");
  projh2X_sig->Scale(50);
  //sprojh2Y_sig->Draw("");
  // projh2Y_sig->Draw("hbar same");
  projh2X_sig->SetLineColor(kRed);
  projh2X_sig->SetLineStyle(1);
  projh2X_sig->SetLineWidth(2);
  l1->Draw("same");
  l1->SetLineWidth(2);
  l1->SetLineStyle(2);

  TGraph *gr4 = make_swapped_graph1(projh2X);
  TGraph *gr5 = make_swapped_graph1(projh2X_sig);


  // draw only for axis
  gr4->Draw("AL");
  gr5->Draw("L");
  //top_pad->Update();
  padprojx->Draw();
  gr5->GetHistogram()->SetMinimum(-50);
  gr5->GetHistogram()->SetMaximum(400);
  
  c->cd(2);
  projh2Y->SetLineColor(kBlue);
  projh2Y->SetFillStyle(0);
  projh2Y->SetLineStyle(1);
  projh2Y->SetLineWidth(2);

  // projh2Y->Draw("hbar");
  projh2Y_sig->Scale(50);
  //sprojh2Y_sig->Draw("");
  // projh2Y_sig->Draw("hbar same");
  projh2Y_sig->SetLineColor(kRed);
  projh2Y_sig->SetLineStyle(1);
  projh2Y_sig->SetLineWidth(2);
  //l2->Draw("same");
  //l2->SetLineWidth(2);
  //l2->SetLineStyle(2);

  TGraph *gr1 = make_swapped_graph(projh2Y);
  TGraph *gr2 = make_swapped_graph(projh2Y_sig);


  // draw only for axis
  gr1->Draw("AL");
  gr2->Draw("L");
  //right_pad->Update();
  padprojy->Update();
  gr1->GetHistogram()->SetMinimum(-50);
  gr1->GetHistogram()->SetMaximum(400);


  set_style();
  //padprojxy->cd();
  cHist->cd();
  //c1->cd();
  TLatex *logo = new TLatex();
  //logo->SetNDC();
  //logo->SetTextSize(belle2_tsize);
  logo->DrawLatex(0.55,0.90, "#bf{#it{Belle II}} simulation");
  logo->DrawLatex(0.55,0.84, " #it{#scale[0.6]{#int} L dt} = 70 fb^{#minus1}");
  logo->DrawLatex(0.55,0.78,"#it{D}^{0}#rightarrow#it{K}^{0}_{S}#it{K}^{0}_{S}");

  TLegend *legend = new TLegend(.75,.80,.95,.95);
  legend->AddEntry( projh2X_sig,"Signal  X50");
  //legend->AddEntry(h2,"Signal");
  legend->AddEntry( projh2X,"Total");
  legend->AddEntry(l1," > 20","l");
  legend->Draw();

  //center_pad->cd();
  c->cd();
  /* TLatex *logo = new TLatex();
  //logo->SetNDC();
  //logo->SetTextSize(belle2_tsize);
  logo->DrawLatex(0.66,0.90, "#bf{#it{Belle II}} simulation");
  logo->DrawLatex(0.64,0.84, " #it{#scale[0.6]{#int} L dt} = 70 fb^{#minus1}");
  logo->DrawLatex(0.65,0.78,"#it{D}^{0}#rightarrow#it{K}^{0}_{S}#it{K}^{0}_{S}");*/

  TLegend *legend1 = new TLegend(.75,.80,.95,.95);
  legend1->AddEntry(h2,"Signal");
  legend1->AddEntry( h1,"Total");
  legend1->Draw();


  

}