#include "TROOT.h"
#include "TSystem.h"
#include <TChain.h>
#include <TFile.h>
#include <memory>  
#include "TTree.h"
#include "TString.h"
#include "TClonesArray.h"
#include <ROOT/RDataFrame.hxx>

int merge()
{
    std::string firstfilename= "pp_2j_LO_H_T_35GeV.root";
    std::string filename2= "pp_4j_LO_H_T_2_35GeV.root";
    std::string output_filename= "pp_2j_LO_w_4j_as_friend.root";
    std::string output_filename2= "friend.root";
    std::string treename="LHEF";

    std::unique_ptr<TFile> first{TFile::Open(firstfilename.c_str())};
    TTree * first_tree= (TTree*)first->Get<TTree>(treename.c_str());

    TFile* output_file= TFile::Open( output_filename.c_str(), "RECREATE" );
    TTree *output_tree = first_tree->CloneTree(0);

    std::unique_ptr<TFile> second{TFile::Open(filename2.c_str())} ;
    TTree *second_tree = (TTree*)second->Get<TTree>(treename.c_str());

    TFile* output_file2= TFile::Open( output_filename2.c_str(), "RECREATE" );
    TTree *output_friend = second_tree->CloneTree(0);


    auto nentries = first_tree->GetEntriesFast();

    for(Long64_t e = 0; e < nentries; e++) {
        first_tree->GetEntry(e); 
        output_tree->Fill();
        second_tree->GetEntry(e);
        output_friend->Fill();
    }

    output_tree->AddFriend(output_friend);
    output_file->Write();
    
//    first->Close();
//    second->Close();
//    output_file->Close();
//    output_file2->Close();


   auto append_func_call=[](ROOT::VecOps::RVec<double> inputArray1,ROOT::VecOps::RVec<double> inputArray2){
        const auto size = inputArray2.size();
        for (size_t i = 0; i < size; i++)
           inputArray1.emplace_back(inputArray2[i]);
        return inputArray1;};
   auto append_func_call_int=[](ROOT::VecOps::RVec<int> inputArray1,ROOT::VecOps::RVec<int> inputArray2){
    const auto size = inputArray2.size();
    for (size_t i = 0; i < size; i++)
       inputArray1.emplace_back(inputArray2[i]);
    return inputArray1;};
    auto append_func_call_uint=[](ROOT::VecOps::RVec<unsigned int> inputArray1,ROOT::VecOps::RVec<unsigned int> inputArray2){
    const auto size = inputArray2.size();
    for (size_t i = 0; i < size; i++)
       inputArray1.emplace_back(inputArray2[i]);
    return inputArray1;};
    auto append_func_call_long=[](ROOT::VecOps::RVec<long long int> inputArray1,ROOT::VecOps::RVec<long long int> inputArray2){
    const auto size = inputArray2.size();
    for (size_t i = 0; i < size; i++)
       inputArray1.emplace_back(inputArray2[i]);
    return inputArray1;};
    auto add_func_call_uint=[](ROOT::VecOps::RVec<unsigned int> inputArray1,ROOT::VecOps::RVec<unsigned int> inputArray2){
    auto Array3 = inputArray1+inputArray2;
    return Array3;};
    auto add_func_call_int=[](ROOT::VecOps::RVec<int> inputArray1,ROOT::VecOps::RVec<int> inputArray2){
    auto Array3 = inputArray1+inputArray2;
    return Array3;};
    auto add_func_call_fBit=[](ROOT::VecOps::RVec<unsigned int> inputArray1,ROOT::VecOps::RVec<unsigned int> inputArray2){
    auto Array3 = (ROOT::VecOps::RVec<int>) inputArray1+(ROOT::VecOps::RVec<int>) inputArray2;
    return Array3;};

    auto df = ROOT::RDataFrame("LHEF", "pp_2j_LO_w_4j_as_friend.root");
    auto df2=df.Redefine("Particle.fUniqueID",append_func_call_uint,{"Particle.fUniqueID","LHEF.Particle.fUniqueID"})
               .Redefine("Particle.fBits",append_func_call_uint,{"Particle.fBits","LHEF.Particle.fBits"})
               .Redefine("Particle.PID",append_func_call_int,{"Particle.PID","LHEF.Particle.PID"})
               .Redefine("Particle.Status",append_func_call_int,{"Particle.Status","LHEF.Particle.Status"})
               .Redefine("Particle.Mother1",append_func_call_int,{"Particle.Mother1","LHEF.Particle.Mother1"})
               .Redefine("Particle.Mother2",append_func_call_int,{"Particle.Mother2","LHEF.Particle.Mother2"})
               .Redefine("Particle.ColorLine1",append_func_call_int,{"Particle.ColorLine1","LHEF.Particle.ColorLine1"})
               .Redefine("Particle.ColorLine2",append_func_call_int,{"Particle.ColorLine2","LHEF.Particle.ColorLine2"})
               .Redefine("Particle.Px",append_func_call,{"Particle.Px","LHEF.Particle.Px"})
               .Redefine("Particle.Py",append_func_call,{"Particle.Py","LHEF.Particle.Py"})
               .Redefine("Particle.Pz",append_func_call,{"Particle.Pz","LHEF.Particle.Pz"})
               .Redefine("Particle.E",append_func_call,{"Particle.E","LHEF.Particle.E"})
               .Redefine("Particle.M",append_func_call,{"Particle.M","LHEF.Particle.M"})
               .Redefine("Particle.PT",append_func_call,{"Particle.PT","LHEF.Particle.PT"})
               .Redefine("Particle.Eta",append_func_call,{"Particle.Eta","LHEF.Particle.Eta"})
               .Redefine("Particle.Phi",append_func_call,{"Particle.Phi","LHEF.Particle.Phi"})
               .Redefine("Particle.Rapidity",append_func_call,{"Particle.Rapidity","LHEF.Particle.Rapidity"})
               .Redefine("Particle.LifeTime",append_func_call,{"Particle.LifeTime","LHEF.Particle.LifeTime"})
               .Redefine("Particle.Spin",append_func_call,{"Particle.Spin","LHEF.Particle.Spin"})
               .Redefine("Particle_size",append_func_call_int,{"Particle_size","LHEF.Particle_size"})
               .Redefine("Event.fUniqueID",append_func_call_uint,{"Event.fUniqueID","LHEF.Event.fUniqueID"})
               .Redefine("Event.Nparticles",add_func_call_int,{"Event.Nparticles","LHEF.Event.Nparticles"})
               .Redefine("Event.ProcessID",append_func_call_int,{"Event.fBits","LHEF.Event.fBits"})
               .Redefine("Event.Weight",append_func_call,{"Event.Weight","LHEF.Event.Weight"})
               .Redefine("Event.ScalePDF",append_func_call,{"Event.ScalePDF","LHEF.Event.ScalePDF"})
               .Redefine("Event.CouplingQED",append_func_call,{"Event.CouplingQED","LHEF.Event.CouplingQED"})
               .Redefine("Event.CouplingQCD",append_func_call,{"Event.CouplingQCD","LHEF.Event.CouplingQCD"})
               .Redefine("Event_size","Event_size+LHEF.Event_size")
               .Redefine("Rwgt.fUniqueID",append_func_call_uint,{"Rwgt.fUniqueID","LHEF.Rwgt.fUniqueID"})
               .Redefine("Rwgt.fBits",append_func_call_uint,{"Rwgt.fBits","LHEF.Rwgt.fBits"})
               .Redefine("Rwgt.Weight",append_func_call,{"Rwgt.Weight","LHEF.Rwgt.Weight"})
               .Redefine("Rwgt_size",add_func_call_int,{"Rwgt_size","LHEF.Rwgt_size"});
//               .Redefine("Event.fBits",add_func_call_fBit,{"Event.fBits","LHEF.Event.fBits"})  ;
//             .Redefine("Event.Number",append_func_call_long,{"Event.Number","LHEF.Event.Number"})
    auto defColNames = df2.GetColumnNames(); // Print columns' names 
    for (auto &&defColName : defColNames) std::cout << defColName << std::endl; 
//    auto d=df2.Describe();//formado de columnas amigo -> "LHEF.Event.Nparticles" 
//    d.Print(); auto d2=df2.Display("Particle.Px"); d2->Print();

     df2.Snapshot("LHEF", "merged_snapshot.root");//    ; 
return 0; }