#include "Riostream.h"

///////////////////////////////////////////////////////////////////
//////// Go4 GUI example script addhistos.C
//          J.Adamczewski, gsi, May 2006
//          JAM May 2015: added support for 2d histograms
// NOTE: to be run in Go4 GUI local command line only!
//       NEVER call this script in remote analysis process!!!
/////// Functionality:
// adds histogram of name2 to histogram of name1
/////// Usage:
// histogram name2 will be scaled by factor.
// (e.g. if factor==-1, his2 is substracted from his1)
// The draw flag switches if the results are displayed each time this makro is called
// if display is switched off, the result histogram is just updated in browser and existing displays
///////
Bool_t addhistos(const char *name1, const char *name2, Double_t factor, Bool_t draw)
{
   if(!TGo4AbstractInterface::Instance() || go4 != TGo4AbstractInterface::Instance()) {
      std::cout <<"FATAL: Go4 gui macro executed outside Go4 GUI!! returning." << std::endl;
      return kFALSE;
   }
   TString fullname1 = go4->FindItem(name1);
   TObject *ob1 = go4->GetObject(fullname1,1000); // 1000=timeout to get object from analysis in ms
   TH1 *his1 = nullptr, *his2 = nullptr;
   if(ob1 && ob1->InheritsFrom("TH1"))
      his1 = (TH1 *) ob1;
   if(!his1) {
      std::cout <<"addhistos could not get histogram "<<fullname1 << std::endl;
      return kFALSE;
   }

   TString fullname2 = go4->FindItem(name2);
   TObject *ob2=go4->GetObject(fullname2,1000); // 1000=timeout to get object from analysis in ms
   if(ob2 && ob2->InheritsFrom("TH1"))
      his2 = (TH1 *) ob2;
   if(!his2) {
      std::cout <<"addhistos could not get histogram "<<fullname2 << std::endl;
      return kFALSE;
   }
   if((his1->GetDimension()) != (his2->GetDimension()))
   {
       std::cout <<"addhistos could not add histograms of different dimensions "<< std::endl;
       return kFALSE;
   }
   TH1 *result = (TH1 *) his1->Clone();
   TString n1 = his1->GetName();
   TString n2 = his2->GetName();
   TString t1 = his1->GetTitle();
   TString t2 = his2->GetTitle();
   TString soper;
   if(factor>0)
      soper.Form(") + %4.1E * (",factor);
   else
      soper.Form(") - %4.1E * (",-1*factor);
   TString finalname = TString("(")+n1+soper+n2+")";
   TString finaltitle = TString("(")+t1+soper+t2+")";
   result->SetName(finalname);
   result->SetTitle(finaltitle);
   result->Sumw2();
   result->Add(his2,factor);
   result->SetDirectory(nullptr);
   TString rname = go4->SaveToMemory("Sums", result, kTRUE);
   std::cout<< "Saved result histogram to " << rname.Data() <<std::endl;
   if(draw) {
      ViewPanelHandle vpanel = go4->StartViewPanel();
      if(result->GetDimension()>1)
      {
          // superimpose mode is not supported for 2d histograms
          go4->DrawItem(rname, vpanel);
      }
      else
      {
        go4->SetSuperimpose(vpanel,kTRUE);
        go4->DrawItem(fullname1, vpanel);
        go4->DrawItem(fullname2, vpanel);
        go4->DrawItem(rname, vpanel);
      }
   }
   return kTRUE;
}