#include <sys/stat.h>
#include <unistd.h>
#include <iostream>     // std::cout
#include <fstream>      // std::ifstream


int DEBUG = 1;

bool File_exists_test(char name[]) {
  struct stat buffer;   
  return (stat (name , &buffer) == 0); 
}


void effplt(){

  char fnam[128];

  float Ratios1[2][20][44];
  float Ratios2[2][20][44];
  float dRatios1[2][20][44];
  float dRatios2[2][20][44];
  int Counts[2][20][44];
  int Norm[2][20][44];
  int TheBin[2][20][44];

  memset(Counts,0,2*20*44*4);
  memset(Norm,0,2*20*44*4);
  memset(TheBin,0,2*20*44*4);

  int dummy;
  float dummy1;
  int a,b,c;
  for (int j=10000; j<10500; j++){ // loop over all files and collect data

    sprintf(fnam,"VER03/tofeff_run%d.dat",j);
    //sprintf(fnam,"tofeff_run%d.dat",j);
    if (File_exists_test(fnam)){

      ifstream INF(fnam);
      for (int n=0; n<2; n++){ // loop over both planes
	for (int k=0;k<20;k++){ // loop over momenta bins
	  for (int xbin=0; xbin<44; xbin++){ // loop over paddles
	    INF>>dummy
	      >>dummy1
	      >>dummy
	      >>dummy1
	      >>a>>b>>c;
	    Counts[n][k][xbin] += a;
	    Norm[n][k][xbin] += b;
	    TheBin[n][k][xbin] +=c;
	  }
	}
      }
    INF.close();
    cout<<".";
    }
  }
  cout<<"done"<<endl;

  float X[44];
  for (int xbin=1; xbin<45; xbin++){
    X[xbin-1] = xbin;
  }

  //TMultiGraph *mgr = new TMultiGraph();
  //TGraph *graphs[2];

  TCanvas *c1 = new TCanvas("c1","A Simple Graph Example",200,10,700,500);

  for (int n=0; n<2; n++){ // loop over both planes
    for (int k=0;k<20;k++){ // loop over momenta bins

      for (int xbin=0; xbin<44; xbin++){ 
	float a = (float)Counts[n][k][xbin];
	float b = (float)Norm[n][k][xbin];
	Ratios1[n][k][xbin] = a/b;
	float e2 = 1./b + a/b/b*(a/b - 1.);
	if (e2>0.){
	  e2 = TMath::Sqrt(e2);
	} else {
	  e2 =0;
	}
	dRatios1[n][k][xbin] = e2;

	a = (float)TheBin[n][k][xbin];
	Ratios2[n][k][xbin] = a/b;
	e2 = 1./b + a/b/b*(a/b - 1.);
	if (e2>0.){
	  e2 = TMath::Sqrt(e2);
	} else {
	  e2 =0;
	}
	dRatios2[n][k][xbin] = e2;
      }



      TGraphErrors *graphs[2];
      graphs[0] = new TGraphErrors(44, X, Ratios1[n][k], NULL, dRatios1[n][k]);
      graphs[0]->SetLineColor(2);
      graphs[0]->SetMarkerColor(2);
      graphs[0]->SetMarkerStyle(21);
      graphs[0]->SetMarkerSize(1.35);
      graphs[1] = new TGraphErrors(44, X, Ratios2[n][k], NULL, dRatios2[n][k]);
      graphs[1]->SetLineColor(4);
      graphs[1]->SetMarkerColor(4);
      graphs[1]->SetMarkerStyle(22);
      graphs[1]->SetMarkerSize(1.35);

      TMultiGraph *mgr = new TMultiGraph();
      TLegend *leg = new TLegend(0.35,0.1,0.65,0.3);
      char legtit[128];
      sprintf(legtit,"Track Momentum %4.1f GeV/c",k*0.5 + 0.5);
      leg->SetHeader(legtit);
      leg->AddEntry(graphs[0],"paddle #pm 1");
      char t1[128];
      sprintf(t1,"paddle only P%d",n);
      leg->AddEntry(graphs[1],t1);
      TLegendEntry *header = (TLegendEntry*)leg->GetListOfPrimitives()->First();
      header->SetTextColor(2);
      header->SetTextSize(.033);
      TList *list = leg->GetListOfPrimitives();
      TObject *First = leg->GetListOfPrimitives()->First();
      header = (TLegendEntry*)list->After(First);
      header->SetTextSize(.025);

      mgr->Add(graphs[0]);
      mgr->Add(graphs[1]);

      mgr->Draw("LAP");
      mgr->GetXaxis()->SetTitle("Paddle Number");
      mgr->GetYaxis()->SetTitle("Efficinecy");
      mgr->GetYaxis()->SetRangeUser(0.,1.);
      sprintf(t1,"Efficinecy Plane %d track p = %4.1f GeV/c",n,k*0.5 + 0.5);
      mgr->GetHistogram()->SetTitle(t1);
      gPad->SetGrid();
      leg->Draw();
      c1->Update();
      char ht[128];
      sprintf(ht,"efficiency_plane%d_momentum%04.1fGeV.pdf",n,k*0.5 + 0.5);
      c1->SaveAs(ht);
      sprintf(ht,"efficiency_plane%d_momentum%04.1fGeV.gif",n,k*0.5 + 0.5);
      c1->SaveAs(ht);
      getchar();
      
    }
  }

}