#include <stdlib.h>
#include <stdio.h>

#include "gp.h"

static int cmp_fitness(const void *d1, const void *d2)
{
	const gp_indiv_t *i1 = d1, *i2 = d2;
	return i1->fitness > i2->fitness;
}

static void gp_sort(gp_pop_t *pop)
{
	qsort(pop->indiv, pop->len, sizeof(gp_indiv_t), cmp_fitness);
}

void gp_setup(gp_pop_t *pop)
{
	int n;
	pop->indiv = malloc(sizeof(gp_indiv_t) * pop->len);
	for(n = 0; n < pop->len; n++) {
		pop->indiv[n].data = pop->create();
		pop->indiv[n].fitness = pop->score(pop->indiv[n].data);
	}
	pop->pop_cnt = 0;
	gp_sort(pop);
}

void gp_iterate(gp_pop_t *pop)
{
	int n, s, delay;

	pop->pop_cnt++;

	/* kill the weakest few and replace them with the strongests */
	for(delay = s = 0, n = pop->len - pop->weak_kill - 1; n < pop->len; n++) {
		pop->clone(pop->indiv[n].data, pop->indiv[s].data);
		pop->mutate(pop->indiv[n].data);
		if (delay > pop->clone_times) {
			delay = 0;
			s++;
		}
	}

	/* score and sort */
	for(n = s; n < pop->len; n++)
		pop->indiv[n].fitness = pop->score(pop->indiv[n].data);
	gp_sort(pop);

}


void gp_dump(FILE *f, gp_pop_t *pop, int max_dump)
{
	int n;
	for(n = 0; n < pop->len; n++) {
		const char *dmp = NULL;
		if ((pop->dump != NULL) && (n < max_dump))
			dmp = pop->dump(pop->indiv[n].data, pop->pop_cnt, n);
		if (dmp == NULL)
			dmp = "n/a";
		fprintf(f, " #%03d %f %s\n", n, pop->indiv[n].fitness, dmp);
	}
}