#include "ptdrHistogramStyle.h"
#include "TStyle.h"
#include "TString.h"
#include "THStack.h"
#include "TLegend.h"
#include "TSystem.h"
#include "TTree.h"
#include "TFile.h"
#include "TH1F.h"
#include "TCanvas.h"
#include <iostream>
#include <vector>

ClassImp(TPTDRHistogramStyle);

TPTDRHistogramStyle::TPTDRHistogramStyle(bool colored):colored(colored)
{
  gSystem->Load("libExRootAnalysisReader");

  int hatchesSpacing=0;//hatches density 1=max,9=min
  hatchStyles.push_back(3008+hatchesSpacing);
  hatchStyles.push_back(3007+hatchesSpacing);
  hatchStyles.push_back(3004+hatchesSpacing);
  hatchStyles.push_back(3006+hatchesSpacing);
  hatchStyles.push_back(3005+hatchesSpacing);
  hatchStyles.push_back(1001+hatchesSpacing);
  hatchStyles.push_back(3003+hatchesSpacing);
  hatchStyles.push_back(3001+hatchesSpacing);
  for(Int_t i=9;i<21;i++)
    hatchStyles.push_back(3000+i);

  nHists=0;
}

TH1F* 
TPTDRHistogramStyle::AddHistogram(TString variableName, TString fileName, 
				  TString lName, Int_t nBins, Double_t min,
				  Double_t max, Double_t weight,
				  TString treeName)
{
  TFile f(fileName);
  TTree *t=(TTree*)f.Get(treeName);
  Double_t variable;
  t->SetBranchAddress(variableName,&variable);
  TH1F* hist = new TH1F(variableName, variableName, nBins, min, max);//bins,min,max
  if(min==0 && max==0) hist->SetBit(TH1::kCanRebin);

  Int_t nEntries = (Int_t)t->GetEntries();
  for(Int_t i=0; i<nEntries; i++){
    t->GetEntry(i);
    hist->Fill(variable);
    if(variable>max) max=variable;
    if(variable<min) min=variable;
  }

  hist->SetFillStyle(hatchStyles[nHists]);
  if(colored)
    hist->SetFillColor(nHists+101);
  else
    hist->SetFillColor(1);
  hist->Scale(weight);
  hist->SetDirectory(0);//avoid removing the histograms from the memory
  THStack::Add(hist);
  legendNames.push_back(lName);
  nHists++;
  return hist;
}

void
TPTDRHistogramStyle::DrawHistograms(TString option)
{
  THStack::Draw(option);
}

void
TPTDRHistogramStyle::DrawLegend()
{
  legend=new TLegend(0.6,0.35,0.9,0.9,"Samples","brNDC");
  for(Int_t i=0;i<GetHists()->GetSize();i++){
    legend->AddEntry(GetHists()->At(i),legendNames[i]);
    //    cout << legendNames[i] << " " << GetHists()->At(i) << endl;
  }
  legend->Draw();
}