%%cpp -d
#include <cstdlib>
#include <vector>
#include <iostream>
#include <map>
#include <string>

#include "TFile.h"
#include "TTree.h"
#include "TString.h"
#include "TSystem.h"
#include "TROOT.h"
#include "TStopwatch.h"

#include "TMVA/Tools.h"
#include "TMVA/Reader.h"

using namespace TMVA;

TString myMethodList = "";

TMVA::Tools::Instance();

std::map<std::string,int> Use;

Use["PDERS"]           = 0;
Use["PDEFoam"]         = 1;
Use["KNN"]             = 1;

Use["LD"]              = 1;

Use["FDA_GA"]          = 0;
Use["FDA_MC"]          = 0;
Use["FDA_MT"]          = 0;
Use["FDA_GAMT"]        = 0;

Use["MLP"] = 0;

#ifdef R__HAS_TMVAGPU
Use["DNN_GPU"] = 1;
Use["DNN_CPU"] = 0;
#else
Use["DNN_GPU"] = 0;
#ifdef R__HAS_TMVACPU
Use["DNN_CPU"] = 1;
#else
Use["DNN_CPU"] = 0;
#endif
#endif

Use["SVM"]             = 0;

Use["BDT"]             = 0;
Use["BDTG"]            = 1;

std::cout << std::endl;
std::cout << "==> Start TMVARegressionApplication" << std::endl;

if (myMethodList != "") {
   for (std::map<std::string,int>::iterator it = Use.begin(); it != Use.end(); it++) it->second = 0;

   std::vector<TString> mlist = gTools().SplitString( myMethodList, ',' );
   for (UInt_t i=0; i<mlist.size(); i++) {
      std::string regMethod(mlist[i]);

      if (Use.find(regMethod) == Use.end()) {
         std::cout << "Method \"" << regMethod << "\" not known in TMVA under this name. Choose among the following:" << std::endl;
         for (std::map<std::string,int>::iterator it = Use.begin(); it != Use.end(); it++) std::cout << it->first << " ";
         std::cout << std::endl;
         return;
      }
      Use[regMethod] = 1;
   }
}

TMVA::Reader *reader = new TMVA::Reader( "!Color:!Silent" );

Float_t var1, var2;
reader->AddVariable( "var1", &var1 );
reader->AddVariable( "var2", &var2 );

Float_t spec1,spec2;
reader->AddSpectator( "spec1:=var1*2",  &spec1 );
reader->AddSpectator( "spec2:=var1*3",  &spec2 );

TString dir    = "datasetreg/weights/";
TString prefix = "TMVARegression";

for (std::map<std::string,int>::iterator it = Use.begin(); it != Use.end(); it++) {
   if (it->second) {
      TString methodName = it->first + " method";
      TString weightfile = dir + prefix + "_" + TString(it->first) + ".weights.xml";
      reader->BookMVA( methodName, weightfile );
   }
}

TH1* hists[100];
Int_t nhists = -1;
for (std::map<std::string,int>::iterator it = Use.begin(); it != Use.end(); it++) {
   TH1* h = new TH1F( it->first.c_str(), TString(it->first) + " method", 100, -100, 600 );
   if (it->second) hists[++nhists] = h;
}
nhists++;

TFile *input(0);
TString fname = "./tmva_reg_example.root";
if (!gSystem->AccessPathName( fname )) {
   input = TFile::Open( fname ); // check if file in local directory exists
}
else {
   TFile::SetCacheFileDir(".");
   input = TFile::Open("http://root.cern/files/tmva_reg_example.root", "CACHEREAD"); // if not: download from ROOT server
}
if (!input) {
   std::cout << "ERROR: could not open data file" << std::endl;
   exit(1);
}
std::cout << "--- TMVARegressionApp        : Using input file: " << input->GetName() << std::endl;

TTree* theTree = (TTree*)input->Get("TreeR");
std::cout << "--- Select signal sample" << std::endl;
theTree->SetBranchAddress( "var1", &var1 );
theTree->SetBranchAddress( "var2", &var2 );

std::cout << "--- Processing: " << theTree->GetEntries() << " events" << std::endl;
TStopwatch sw;
sw.Start();
for (Long64_t ievt=0; ievt<theTree->GetEntries();ievt++) {

   if (ievt%1000 == 0) {
      std::cout << "--- ... Processing event: " << ievt << std::endl;
   }

   theTree->GetEntry(ievt);

   // Retrieve the MVA target values (regression outputs) and fill into histograms
   // NOTE: EvaluateRegression(..) returns a vector for multi-target regression

   for (Int_t ih=0; ih<nhists; ih++) {
      TString title = hists[ih]->GetTitle();
      Float_t val = (reader->EvaluateRegression( title ))[0];
      hists[ih]->Fill( val );
   }
}
sw.Stop();
std::cout << "--- End of event loop: "; sw.Print();

TFile *target  = new TFile( "TMVARegApp.root","RECREATE" );
for (Int_t ih=0; ih<nhists; ih++) hists[ih]->Write();
target->Close();

std::cout << "--- Created root file: \"" << target->GetName()
          << "\" containing the MVA output histograms" << std::endl;

delete reader;

std::cout << "==> TMVARegressionApplication is done!" << std::endl << std::endl;