#include <iostream>
#include <sstream>
#include <string>
#include <vector>
//Root
#include "TMath.h"
#include "TFile.h"
#include "TH1.h"
#include "TH2.h"
#include <TTree.h>
void MinimalTreeMacro(
) { TTree* _tree_pars = nullptr;
    TFile* _file_pars = nullptr;
    int NParams = 10;
    double param_values[NParams];

    for (unsigned int itoy = 0; itoy < 2; itoy++) {
        int N = 5;
        bool tree_spectra_created = 1;
        TH1 *pdfs[N];
        int pdfsDim[] = {1, 1, 2, 2, 2};
        TH1D *blank1Dhist = new TH1D();
        TH2D *blank2Dhist = new TH2D();
        for (int ih = 0; ih < N; ih++) {
            pdfs[ih] = nullptr;
        }
        if (!_file_pars) {
            _file_pars = new TFile("ParameterFile.root", "RECREATE");
            tree_spectra_created = 0;
        }
        if (!_tree_pars) {
            _tree_pars = new TTree("marg_parameter_values", "Input parameters used for toys");
            for (int ip = 0; ip < NParams; ip++) {
                std::string param_name = "Parameter " + std::to_string(ip);
                std::string branch_info = param_name + "/D";
                _tree_pars->Branch(param_name.c_str(), &(param_values[ip]), branch_info.c_str());
            }
        }
        for (int ip = 0; ip < NParams; ip++) {
            param_values[ip] = ip;
        }

        for (unsigned int idata = 0; idata < N; idata++) {
            // Determine if 1D or 2D
            if (pdfsDim[idata] == 1) { //If 1D hist
                TH1D *curr_pdf = blank1Dhist;
                pdfs[idata] = (TH1 *) curr_pdf;
            } else if (pdfsDim[idata] == 2) { //If 2D hist
                TH2D *curr_pdf = blank2Dhist;
                pdfs[idata] = (TH1 *) curr_pdf;
            }
        }
    //Setting up branch for spectra. N.B: This is done after the object type assignment above to avoid errors in setting up TH1 branches (abstract base).
    if (!tree_spectra_created) {
        for (unsigned int imodel = 0; imodel < N; imodel++) {
            std::string model_name = "Spectra " + std::to_string(imodel);
            _tree_pars->Branch(model_name.c_str(), &(pdfs[imodel]), 32000, 0); //This is the line creating the error.
        }
        tree_spectra_created = 1;
    }



    // If this is the final toy, write the tree to a new file
    _tree_pars->Fill();

}

    _file_pars->cd();
    _tree_pars->Write();

    std::vector<double> best_fit_toy;
    best_fit_toy  = {1.1, 1.2};
    const char* BestFitToy = "chi2_best_fit_toy";
    const char* OutputFile = "parameter_values_with_ChiSquareDataFrame.root";
    const char* BaseTTree = "marg_parameter_values";
    const char* ParameterFile = "ParameterFile.root";

    ROOT::RDataFrame df(BaseTTree, ParameterFile);
    df.Define(BestFitToy, [best_fit_toy](ULong64_t idx){ return best_fit_toy.at(idx); }, {"rdfentry_"})
            .Snapshot(BaseTTree, OutputFile);
}