/**
   \file kmm_stat.hpp
   \brief maximum-liklihood statistic
   \author Junhua Gu
 */

#ifndef KMM_STAT_HPP
#define KMM_STAT_HPP
#define OPT_HEADER
#include <core/fitter.hpp>
#include <math/vector_operation.hpp>
#include <distributions/kmm_component.hpp>
#include <iostream>
#include <cassert>


using std::cout;using std::endl;
namespace opt_utilities
{

  /**
     \brief c-statistic, max-likelihood method
     \tparam Ty the return type of model
     \tparam Tx the type of the self-var
     \tparam Tp the type of model parameter
     \tparam Ts the type of the statistic
     \tparam Tstr the type of the string used
   */
  template<typename T,typename Ts,typename Tstr>
  class kmm_stat
    :public statistic<optvec<T>,optvec<T>,optvec<T>,Ts,Tstr>
  {
  private:
    bool verb;
    int n;
  public:
    kmm_stat()
      :verb(true)
    {}

    void verbose(bool v)
    {
      verb=v;
    }

    const char* do_get_type_name()const
    {
      return "kmm likelihood";
    }

  public:

    statistic<optvec<T>,optvec<T>,optvec<T>,Ts,Tstr>* do_clone()const
    {
      // return const_cast<statistic<Ty,Tx,Tp>*>(this);
      return new kmm_stat<T,Ts,Tstr>(*this);
    }

    Ts do_eval(const optvec<T>& p)
    {
      Ts result(0);
      
      kmm_component<T>* kmm=
	dynamic_cast<kmm_component<T>* >(&const_cast<model<optvec<T>,optvec<T>,optvec<T>,std::string>&>(this->get_fitter().get_model()));
      
      if(kmm==0)
	{
	  throw opt_exception("model is not a kmm component");
	}
      
      for(int i=(this->get_data_set()).size()-1;i>=0;--i)
	{
	  optvec<T> unsummed_possibility(kmm->eval_unsumed(this->get_data_set().get_data(i).get_x(),p));
	  T maxp=*max_element(unsummed_possibility.begin(),unsummed_possibility.end());
	  T logp=std::log(maxp);
	  result-=this->get_data_set().get_data(i).get_y()[0]*logp;
	}

      if(verb)
	{
	  n++;
	  if(n%10==0)
	    {
	      cout<<"a:"<<result<<"\t";
	      for(size_t i=0;i<get_size(p);++i)
		{
		  cout<<get_element(p,i)<<",";
		}
	      cout<<endl;
	    }
	  
	}
      return result;
    }
  };
}

#endif
//EOF