/* See {nmsim_group_neuron_sim.h} */
/* Last edited on 2019-07-04 19:57:48 by jstolfi */

#define _GNU_SOURCE
#include <stdint.h>
#include <stdlib.h>
#include <assert.h>

#include <bool.h>
#include <affirm.h>

#include <nmsim_class_neuron.h>
#include <nmsim_group_neuron_state.h>
#include <nmsim_cohort_neuron_state.h>
#include <nmsim_cohort_neuron_sim.h>

#include <nmsim_group_neuron_sim.h>

void nmsim_group_neuron_sim_do_firings
  ( nmsim_group_neuron_state_t *st, 
    nmsim_class_neuron_t *nclass,
    double *rhoP,
    double *rhoHP
  )
  {
    int32_t nco = st->nc;  // Number of cohorts in current state.
    int32_t ncn = nco+1;    // Number of cohorts in new state.
    
    /* Make room for one more cohort: */
    nmsim_cohort_neuron_state_vec_expand(&(st->cs), ncn);
    
    /* The state of the new cohort of age zero: */
    nmsim_cohort_neuron_state_t cs_new_fire;
    nmsim_cohort_neuron_state_clear(&cs_new_fire);
    
    double rho = 0.0;  /* Group firing rate. */
    double rhoH = 0.0; /* Group firing rate weighted by output modulators {H[k]}. */
    int32_t k;
    for (k = nco; k > 0; k--)
      { /* Update state of cohort {S[k,t]} and evolve it to time {t+1}: */
        nmsim_cohort_neuron_state_t *cs_k = &(st->cs.e[k]); /* Original cohort age {k}. */
        nmsim_cohort_neuron_state_t *cs_k1 = &(st->cs.e[k+1]); /* New cohort of duds, age {k+1}. */
        nmsim_cohort_neuron_state_t cs_k_fire; /* Cohort data of firers from age {k}. */
        double rho_k = nmsim_cohort_neuron_sim_do_firings(cs_k, nclass, &cs_k_fire, cs_k1);
        
        /* Accumulate group firing rate: */
        double H_k = cs_k->H;
        rho += cs_k->eta*rho_k;
        rhoH += cs_k->eta*rho_k*H_k;

        /* Merge the part of the cohort {k} that fired into {cs_new_fire}: */
        bool_t ok = nmsim_cohort_neuron_state_merge(&cs_k_fire, &cs_new_fire);
        assert(ok);
      }
    /* Save new age 0 cohort with everybody who fired: */
    st->cs.e[0] = cs_new_fire;
    
    /* We have one additional cohort: */
    st->nc = ncn;
    
    /* Return the group's overall firing rate: */
    (*rhoP) = rho;
    (*rhoHP) = rhoH;
  }

void nmsim_group_neuron_sim_update_potentials
  ( nmsim_group_neuron_state_t *st, 
    double J_avg,
    double J_dev, 
    nmsim_class_neuron_t *nclass
  )
  {
    int32_t nc = st->nc;  // Number of cohorts in current state.
    
    int32_t k;
    for (k = 0; k <= nc; k++)
      { /* Update state of cohort {S[k,t]} with total inputs: */
        nmsim_cohort_neuron_state_t *cs_k = &(st->cs.e[k]); /* Original cohort age {k}. */
        nmsim_cohort_neuron_sim_update_potentials(cs_k, k, nclass, J_avg, J_dev);
      }
   
    /* Collapse any insignificant cohorts at the end: */
    while (nc > 0)
      { nmsim_cohort_neuron_state_t *cs_k = &(st->cs.e[nc-1]); 
        nmsim_cohort_neuron_state_t *cs_k1 = &(st->cs.e[nc]); 
        bool_t ok = nmsim_cohort_neuron_state_merge(cs_k1, cs_k);
        if (! ok) { break; }
        nc--;
      }
    st->nc = nc;
  }