#ifndef OBS_PHI2_HIST_HPP
#define OBS_PHI2_HIST_HPP

#include "latlib/o815/o815.h"

#include "latlib/writeout.h"

#include "latlib/obstat.hpp"

#include <iostream>

using namespace std;

class obs_phi2_hist : public o815::obs {

public:
  struct obsmem {
    double phi2;
  };
  obs_phi2_hist(o815 *_O815);
  
private:
  void _start() {}
  void _meas(bool loadedobs, const int& nthmeas);
  void _finish() {}
  obsmem* OM;
  void phi2Compute();
  sim *Sim;
};

obs_phi2_hist::obs_phi2_hist(o815 *_O815) : o815::obs("phi2", 
						      _O815->paraQ->getParaNames() + "nthstep:phi2", 
						      _O815, sizeof(obsmem), "_hist") {
  OM = (obsmem*)obsMem;
  Sim = (sim*)O815->Sim;
}

void obs_phi2_hist::_meas(bool loadedobs, const int& nthmeas) {
  if (!loadedobs)
    phi2Compute();
  
  *out << O815->paraQ->getParaVals();
  *out << "\t" << ( Sim->nequi + (nthmeas+1)*Sim->nskip );
  *out << "\t" << OM->phi2 << endl;
};

void obs_phi2_hist::phi2Compute()
{
  OM->phi2 = 0;
  
  for (int ix = 0; ix < Sim->LSIZE2; ix++)
    OM->phi2 += norm( Sim->conf[ix].phi );

  OM->phi2 /= Sim->LSIZE2;
}

#endif