#include "MCATNLO/Showers/Splitting_Function_Group.H"
#include "ATOOLS/Org/Exception.H"
#include "ATOOLS/Math/Random.H"

using namespace MCATNLO;
using namespace ATOOLS;
using namespace std;

ostream& MCATNLO::operator<<(std::ostream& str, Splitting_Function_Group &group) {
  str<<"Splitting_Function_Group : "<<group.m_lastint<<endl;
  for (std::vector<Splitting_Function_Base *>::iterator splitter=group.m_splittings.begin();
       splitter!=group.m_splittings.end();splitter++) {
    str<<(**splitter);
  }
  str<<"-------------------------------------------------------------"<<endl;
  return str;
}

Splitting_Function_Group::~Splitting_Function_Group() {
  m_splitter=m_splittings.begin();
  do {
    if (*m_splitter) { delete (*m_splitter); (*m_splitter=NULL); }
    m_splitter = m_splittings.erase(m_splitter);
  } while (m_splitter!=m_splittings.end());
  m_splittings.clear();
}


void Splitting_Function_Group::Add(Splitting_Function_Base * split) {
  m_splittings.push_back(split);
  m_partint.push_back(0.0);
}


void Splitting_Function_Group::SelectOne()
{
  double disc(ran->Get()*m_lastint);
  size_t l(0), r(m_splittings.size()-1), c((l+r)/2);
  double a(m_partint[c]);
  while (r-l>1) {
    if (disc<a) r=c;
    else l=c;
    c=(l+r)/2;
    a=m_partint[c];
  }
  if (disc<m_partint[l]) r=l;
  if (r>=m_splittings.size()) THROW(fatal_error,"Internal error");
  m_splitter = m_splittings.begin();
  for (size_t i(0);i<r;++i) ++m_splitter;
  p_selected=*m_splitter;
}

double Splitting_Function_Group::OverIntegrated(const double zmin,const double zmax,
						const double scale,const double xbj) {
  for (size_t i(0);i<m_splittings.size();++i)
    m_partint[i] = m_lastint += m_splittings[i]->OverIntegrated(zmin,zmax,scale,xbj); 
  return m_lastint;
}


double Splitting_Function_Group::operator() (const double z,const double y,
					     const double eta,const double scale,
					     const double Q2,const Color_Info &ci,Cluster_Amplitude *const sub) { 
  return (*p_selected)(z,y,eta,scale,Q2,ci,sub); 
}

double Splitting_Function_Group::Overestimated(const double z,const double y) { 
  return p_selected->Overestimated(z,y); 
}

double Splitting_Function_Group::RejectionWeight(const double z,const double y,
						 const double eta,const double scale,const double Q2) { 
  return p_selected->RejectionWeight(z,y,eta,scale,Q2); 
}

double Splitting_Function_Group::Z() { 
  return p_selected->Z(); 
}         

void Splitting_Function_Group::ClearSpecs()
{
  m_specs.clear();
  for (m_splitter=m_splittings.begin();m_splitter!=m_splittings.end();m_splitter++) 
    (*m_splitter)->ClearSpecs();
}

void Splitting_Function_Group::ResetLastInt()
{
  m_lastint=0.0;
  for (m_splitter=m_splittings.begin();m_splitter!=m_splittings.end();m_splitter++) 
    (*m_splitter)->ResetLastInt();
}