// Copyright (C) 2010, Guy Barrand. All rights reserved.
// See the file tools.license for terms.

#ifndef tools_histo_h1
#define tools_histo_h1

#include "b1"

namespace tools {
namespace histo { //have that for h1 ?

//TC is for a coordinate.
//TN is for a number of entries.
//TW is for a weight.
//TH is for a height. Should be the same as TW.

template <class TC,class TN,class TW,class TH>
class h1 : public b1<TC,TN,TW,TH> {
  typedef b1<TC,TN,TW,TH> parent;
public:
  typedef typename b1<TC,TN,TW,TH>::bn_t bn_t;
protected:
  virtual TH get_bin_height(int a_offset) const { //TH should be the same as TW
    return parent::m_bin_Sw[a_offset];
  }
public:
  virtual TH bin_error(int aI) const { //TH should be the same as TW
    if(parent::m_bin_number==0) return 0;
    bn_t offset;
    if(!parent::m_axes[0].in_range_to_absolute_index(aI,offset)) return 0;
    return ::sqrt(parent::m_bin_Sw2[offset]);
  }

public:
  bool multiply(TW aFactor){
    if(!parent::base_multiply(aFactor)) return false;
    parent::update_fast_getters();
    return true;
  }
  bool scale(TW aFactor) {return multiply(aFactor);}

  void copy_from_data(const histo_data<TC,TN,TW>& a_from) {
    parent::base_from_data(a_from);
  }
  histo_data<TC,TN,TW> get_histo_data() const {
    return parent::base_get_data();
  }

  bool reset() {
    parent::base_reset();
    parent::update_fast_getters();
    return true;
  }

  bool fill(TC aX,TW aWeight = 1) {
    //m_coords[0] = aX;
    //return fill_bin(m_coords,aWeight);
    if(parent::m_dimension<=0) return false;

    bn_t offset;
    if(!parent::m_axes[0].coord_to_absolute_index(aX,offset)) return false;

    parent::m_bin_entries[offset]++;
    parent::m_bin_Sw[offset] += aWeight;
    parent::m_bin_Sw2[offset] += aWeight * aWeight;
  
    TC xw = aX * aWeight;
    TC x2w = aX * xw;
    parent::m_bin_Sxw[offset][0] += xw;
    parent::m_bin_Sx2w[offset][0] += x2w;
    return true;
  }

  bool add(const h1& a_histo){
    parent::base_add(a_histo);
    parent::update_fast_getters();
    return true;
  }
  bool subtract(const h1& a_histo){
    parent::base_subtract(a_histo);
    parent::update_fast_getters();
    return true;
  }

  bool multiply(const h1& a_histo) {  
    if(!parent::base_multiply(a_histo)) return false;
    parent::update_fast_getters();
    return true;
  }
  
  bool divide(const h1& a_histo) {
    if(!parent::base_divide(a_histo)) return false;
    parent::update_fast_getters();
    return true;
  }

  bool gather_bins(unsigned int a_factor) { //for exa 2,3.
    if(!a_factor) return false;

    // actual bin number must be a multiple of a_factor.
    
    const histo::axis<TC>& _axis = parent::axis();

    bn_t n = _axis.bins();
    if(!n) return false;

    bn_t new_n = n/a_factor;
    if(a_factor*new_n!=n) return false;

    h1* new_h = 0;
    if(_axis.is_fixed_binning()) {
      new_h = new h1(parent::m_title,
                     new_n,_axis.lower_edge(),_axis.upper_edge());
    } else {
      const std::vector<TC>& _edges = _axis.edges();
      std::vector<TC> new_edges(new_n+1);
      for(bn_t ibin=0;ibin<new_n;ibin++) {
        new_edges[ibin] = _edges[ibin*a_factor];
      }
      new_edges[new_n] = _edges[n]; //upper edge.
      new_h = new h1(parent::m_title,new_edges);
    }
    if(!new_h) return false;

    bn_t offset,new_offset,offac;
    for(bn_t ibin=0;ibin<new_n;ibin++) {
      new_offset = ibin+1;
      offset = a_factor*ibin+1;
      for(unsigned int ifac=0;ifac<a_factor;ifac++) {
        offac = offset+ifac;
        new_h->m_bin_entries[new_offset] += parent::m_bin_entries[offac];
        new_h->m_bin_Sw[new_offset] += parent::m_bin_Sw[offac];
        new_h->m_bin_Sw2[new_offset] += parent::m_bin_Sw2[offac];
        new_h->m_bin_Sxw[new_offset][0] += parent::m_bin_Sxw[offac][0];
        new_h->m_bin_Sx2w[new_offset][0] += parent::m_bin_Sx2w[offac][0];
      }
    }

    //underflow :
    new_offset = 0;
    offac = 0;
    new_h->m_bin_entries[new_offset] = parent::m_bin_entries[offac];
    new_h->m_bin_Sw[new_offset] = parent::m_bin_Sw[offac];
    new_h->m_bin_Sw2[new_offset] = parent::m_bin_Sw2[offac];
    new_h->m_bin_Sxw[new_offset][0] = parent::m_bin_Sxw[offac][0];
    new_h->m_bin_Sx2w[new_offset][0] = parent::m_bin_Sx2w[offac][0];

    //overflow :
    new_offset = new_n+1;
    offac = n+1;
    new_h->m_bin_entries[new_offset] = parent::m_bin_entries[offac];
    new_h->m_bin_Sw[new_offset] = parent::m_bin_Sw[offac];
    new_h->m_bin_Sw2[new_offset] = parent::m_bin_Sw2[offac];
    new_h->m_bin_Sxw[new_offset][0] = parent::m_bin_Sxw[offac][0];
    new_h->m_bin_Sx2w[new_offset][0] = parent::m_bin_Sx2w[offac][0];

    *this = *new_h;
    return true;
  }

public:
  h1(const std::string& a_title,bn_t aXnumber,TC aXmin,TC aXmax)
  :parent(a_title,aXnumber,aXmin,aXmax){}

  h1(const std::string& a_title,const std::vector<TC>& aEdges)
  :parent(a_title,aEdges){}

  virtual ~h1(){}
public:
  h1(const h1& a_from): parent(a_from){}
  h1& operator=(const h1& a_from){
    parent::operator=(a_from);
    return *this;
  }
};

}}

#endif