#ifndef ZLIST_H
#define ZLIST_H

#include <stdlib.h>
#include <stdio.h>
#ifdef __cplusplus
extern "C" {
#endif
#ifndef WARN_UNUSED_RESULT
#define WARN_UNUSED_RESULT __attribute__ ((warn_unused_result))
#endif

#pragma GCC poison new_zlist free_zlist remove_zlist_entry
#ifndef append_zlist_entry
#define append_zlist_entry(X, Y) zlist_append(X, Y)
#endif
#ifndef prepend_zlist_entry
#define prepend_zlist_entry(X, Y) zlist_prepend(X, Y)
#endif
#ifndef find_zlist_head
#define find_zlist_head(X) zlist_head(X)
#endif
#ifndef find_zlist_tail
#define find_zlist_tail(X) zlist_tail(X)
#endif
#ifndef insert_zlist_entry
#define insert_zlist_entry(X, Y, Z) zlist_insert(X, Y, Z)
#endif

/**
 * Iterate over a list, allowing data interaction during each loop.
 *
 * @param list The list to iterate over, starting at znode @p list
 * @param l A zlist pointer to use as an iterator
 * @param data The pointer that zlist znode data will be set to
 *
 * @ingroup zlist
 */
#define ZLIST_FOR(list, l, data) \
	for (l = list, data = zlist_data_get(l); l; l = zlist_next(l), data = zlist_data_get(l))

/**
 * Iterate over a list, allowing data interaction during each loop but storing an extra pointer to allow for node deletion.
 *
 * @param list The list to iterate over, starting at znode @p list
 * @param l A zlist pointer to use as an iterator
 * @param n The next list node after l; do not free this.
 * @param data The pointer that zlist znode data will be set to
 *
 * @ingroup zlist
 */
#define ZLIST_FOR_SAFE(list, l, n, data) \
	for (l = list, n = zlist_next(l), data = zlist_data_get(l); l; l = n, n = zlist_next(l), data = zlist_data_get(l))

/**
 * Iterate over a list backwards, allowing data interaction during each loop.
 *
 * @param list The list to iterate over, starting at znode @p list
 * @param l A zlist pointer to use as an iterator
 * @param data The pointer that zlist znode data will be set to
 *
 * @ingroup zlist
 */
#define ZLIST_FOR_REVERSE(list, l, data) \
	for (l = list, data = zlist_data_get(l); l; l = zlist_prev(l), data = zlist_data_get(l))

/**
 * Iterate over a list, unlinking nodes and allowing data interaction during each loop.
 *
 * @param list The list to iterate over, starting at znode @p list
 * @param data The pointer that zlist znode data will be set to
 *
 * @ingroup zlist
 */
#define ZLIST_FREE(list, data) \
	for (data = zlist_data_get(list); list; list = zlist_list_remove(list), data = zlist_data_get(list))


typedef int zlist_magic;

struct _zlist_data;
typedef struct _zlist_data zlist_data;

struct _zlist
{
	zlist_data *zdata;
	struct _zlist *prev;
	struct _zlist *next;
	void *data;
};
typedef struct _zlist zlist;


int zlist_init();
int zlist_shutdown();
void *zlist_data_get(const zlist *znode) WARN_UNUSED_RESULT;
zlist *zlist_next(const zlist *znode) WARN_UNUSED_RESULT;
zlist *zlist_prev(const zlist *znode) WARN_UNUSED_RESULT;
zlist *zlist_append(zlist *list, void *data) WARN_UNUSED_RESULT;
zlist *zlist_prepend(zlist *list, void *data) WARN_UNUSED_RESULT;
zlist *zlist_head(const zlist *znode) WARN_UNUSED_RESULT;
zlist *zlist_tail(const zlist *znode) WARN_UNUSED_RESULT;
zlist *zlist_data_remove(zlist *list, void *data) WARN_UNUSED_RESULT;
zlist *zlist_list_remove(zlist *entry) WARN_UNUSED_RESULT;
zlist *zlist_insert(zlist *prev, zlist *next, void *data) WARN_UNUSED_RESULT;
void *zlist_data_find(zlist *list, void *data);
zlist *zlist_list_find(zlist *list, zlist *znode);
zlist *zlist_Nth(zlist *list, int list_number);
int zlist_count(zlist *list);
void zlist_free(zlist *znode);

#ifdef __cplusplus
}
#endif

#endif // ZLIST_H