#include "TCanvas.h"
#include "TH1.h"
#include "TF1.h"
#include "TLatex.h"

#include <math.h>

#define KPI_COLOR 2
#define KP_COLOR 3
#define PPI_COLOR 4
#define DEDX_COLOR 2

#define OOH_I_HATE_THAT_UGLY_GRID

double tdiff(double *x,double *m) {
  double r = 140;
  double rbc1 = sqrt(1+m[0]*m[0]/(x[0]*x[0]))/29.98;
  double rbc2 = sqrt(1+m[1]*m[1]/(x[0]*x[0]))/29.98;
  return r*(rbc2-rbc1)*10.0;
}

double cotdedx(double *x, double *par) {
  double a01 = -55.190;
  double a02 = -10.171;
  double b = 36.035;
  double c00 = 32.195;
  double c01 = 5.8856;
  double sgdedx = 82;
  double offset = 32.1;
  double scale = 0.4;
  double nctc = 20;

  double p = x[0];
  double m1 = par[0];
  double m2 = par[1];

  double z1 = p/m1;
  double z2 = p/m2;
  double beta1 = sqrt(1/(1+1/(z1*z1)));
  double beta2 = sqrt(1/(1+1/(z2*z2)));
  double dedx1 = (c01*log(z1/(b+z1))+c00)/(beta1*beta1) +
                 (beta1-1)*(a01+(beta1-1)*a02);
  double dedx2 = (c01*log(z2/(b+z2))+c00)/(beta2*beta2) +
                 (beta2-1)*(a01+(beta2-1)*a02);
  double ededx = (sgdedx+(dedx2*1.25-offset)*scale)/nctc;
  return fabs(dedx1-dedx2)/ededx;
}

void TofSeparation() {
  gROOT->SetStyle("Plain");

  TCanvas *c1 = new TCanvas("c1","TOF Separation",0,0,600,500);
  c1->cd();
  TH1F *h = gPad->DrawFrame(0.5,0,5,5);
#ifndef OOH_I_HATE_THAT_UGLY_GRID
  gPad->SetGridx();
  gPad->SetGridy();
#endif
  h->GetXaxis()->SetTitle("Momentum (GeV/c)");
  h->GetXaxis()->SetTitleFont(52);
  h->GetXaxis()->SetLabelFont(52);
  h->GetYaxis()->SetTitle("Separation power (#sigma)");
  h->GetYaxis()->SetTitleFont(52);
  h->GetYaxis()->SetLabelFont(52);
  h->GetXaxis()->SetNdivisions(510);
  h->GetYaxis()->SetNdivisions(505);

  TF1 *fkpi = new TF1("fkpi",tdiff,0.5,5,2);
  fkpi->SetNpx(500);
  fkpi->SetParameters(0.13956995,0.493677);
  fkpi->SetLineColor(KPI_COLOR);
  fkpi->SetLineWidth(3);
  fkpi->Draw("SAME");

  TF1 *fkp = new TF1("fkp",tdiff,0.5,5,2);
  fkp->SetNpx(500);
  fkp->SetParameters(0.493677,0.93827200);
  fkp->SetLineColor(KP_COLOR);
  fkp->SetLineWidth(3);
  fkp->Draw("SAME");

  TF1 *fppi = new TF1("ppi",tdiff,0.5,5,2);
  fppi->SetNpx(500);
  fppi->SetParameters(0.13956995,0.93827200);
  fppi->SetLineColor(PPI_COLOR);
  fppi->SetLineWidth(3);
  fppi->Draw("SAME");

  TF1 *fcot = new TF1("cot",cotdedx,0.5,5.0,2);
  fcot->SetNpx(500);
  fcot->SetParameters(0.13956995,0.493677);
  fcot->SetLineColor(DEDX_COLOR);
  fcot->SetLineStyle(2);
  fcot->SetLineWidth(3);
  fcot->Draw("SAME");

  TLatex *labels[5];
  labels[0] = new TLatex(0.47,0.62,"p-#pi");
  labels[1] = new TLatex(0.36,0.47,"K-p");
  labels[2] = new TLatex(0.24,0.65,"K-#pi");
  labels[3] = new TLatex(0.19,0.29,"K-#pi from ");
  labels[4] = new TLatex(0.17,0.25,"COT dE/dx");
  for ( int i=0; i<5; i++ ) {
    labels[i]->SetNDC();
    labels[i]->SetTextFont(52);
    labels[i]->Draw();
  }
  c1->Print("dtof.eps");
}