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

#include "list.h"

typedef struct {
	int hp;
	list_t node;
	char name[1]; /* must be the last member, lager than 0. */
} champion_t;

static void print_champs(const char *msg, const list_t *champs)
{
	const list_t *node;

	printf("%s\n", msg);

	list_for_each(node, champs) {
		const champion_t *champ = list_entry(node, champion_t, node);
		printf("name:%s  hp:%d\n", champ->name, champ->hp);
	}
}

static champion_t *new_champ(const char *name, const int hp)
{
	champion_t *champ = (champion_t *)malloc(sizeof(*champ) + strlen(name));
	champ->hp = hp;
	list_init(&champ->node);
	strcpy(champ->name, name);
	return champ;
}

static void add_champ(champion_t *champ, list_t *list)
{
	list_add(&champ->node, list);
}

static void del_champ(champion_t *champ)
{
	list_del(&champ->node);
}

static void destroy_champs(list_t *champs)
{
	while (!list_is_empty(champs)) {
		champion_t *champ = list_entry(champs->next, champion_t, node);
		del_champ(champ);
		free(champ);
	}
}

static void sort_champs(list_t *champs, int (*cmp)(const void *, const void *))
{
	list_t *node;
	int nr_champs = 0;

	list_for_each(node, champs)
		nr_champs++;

	long *array = (long *)malloc(sizeof(array[0]) * nr_champs);

	nr_champs = 0;
	list_for_each(node, champs) {
		champion_t *champ = list_entry(node, champion_t, node);
		array[nr_champs++] = (long)champ;
	}

	qsort(array, nr_champs, sizeof(array[0]), cmp);
	
	while(nr_champs-- > 0) {
		champion_t *champ = (champion_t *)array[nr_champs];
		list_del(&champ->node);
		list_add(&champ->node, champs);
	}

	free(array);
}

static int compare_hp(const void *_a, const void *_b)
{
	const champion_t * const a = *(const champion_t * const * const)_a;
	const champion_t * const b = *(const champion_t * const * const)_b;
	return a->hp - b->hp;
}

static int compare_name(const void *_a, const void *_b)
{
	const champion_t * const a = *(const champion_t * const * const)_a;
	const champion_t * const b = *(const champion_t * const * const)_b;
	return strcmp(a->name, b->name);
}

int main(void)
{
	list_t champions;

	list_init(&champions);
	add_champ(new_champ("abc", 10), &champions);
	add_champ(new_champ("ghi", 5), &champions);
	add_champ(new_champ("def", 20), &champions);
	print_champs("--list--", &champions);

	sort_champs(&champions, compare_hp);
	print_champs("--by hp--", &champions);

	sort_champs(&champions, compare_name);
	print_champs("--by name--", &champions);

	destroy_champs(&champions);

	return 0;
}