#include <Utility.h>
#include <TDatabasePDG.h>
#include <TParticlePDG.h>

ClassImp(qaUtility);

qaUtility *qaUtility::fUtility = nullptr;
;

qaUtility::qaUtility() : Nevents(-1),
                         debug(0),
                         format("mctree")
{
}

qaUtility::~qaUtility()
{
}

qaUtility *qaUtility::GetInstance()
{
  if (fUtility == nullptr)
  {
    fUtility = new qaUtility();
  }
  return fUtility;
}

TChain *qaUtility::initChain(const TString &inputFileName, const char *chainName)
{
  TChain *chain = new TChain(chainName);
  std::ifstream file(inputFileName.Data());
  std::string line;
  while (std::getline(file, line))
  {
    chain->Add(line.c_str());
  }

  return chain;
}

std::vector<Float_t> qaUtility::ParseVector(std::string _input)
{
  std::vector<Float_t> vB;

  std::istringstream iss(_input);

  std::copy(std::istream_iterator<Float_t>(iss),
            std::istream_iterator<Float_t>(),
            std::back_inserter(vB));

  return vB;
}

Double_t qaUtility::GetCharge(Int_t pdg)
{
  auto particle = (TParticlePDG *)TDatabasePDG::Instance()->GetParticle(pdg);
  if (!particle)
    return error_code;
  return particle->Charge() / 3.;
}

Int_t qaUtility::GetPdgId(Int_t pdg)
{
  if (pdg == vpdg.at(1))
    return 1;
  if (pdg == vpdg.at(2))
    return 2;
  if (pdg == vpdg.at(3))
    return 3;
  if (pdg == vpdg.at(4))
    return 4;
  if (pdg == vpdg.at(6))
    return 6;
  if (pdg == vpdg.at(7))
    return 7;
  if (pdg == vpdg.at(8))
    return 8;
  if (pdg == vpdg.at(9))
    return 9;
  return -1;
}

Double_t qaUtility::GetBeamP(Double_t sqrtSnn)
{
  double m_target = 0.938;
  double m_beam = 0.938;
  return sqrt( pow((pow(sqrtSnn,2) - pow(m_target,2) - pow(m_beam,2))/(2*m_target), 2) - pow(m_beam,2) );
}