/*
 * Copyright (c) 2009 Lukas Mejdrech
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup libc
 *  @{
 */

/** @file
 *  Integer to generic type map.
 */

#ifndef LIBC_INT_MAP_H_
#define LIBC_INT_MAP_H_

#include <errno.h>
#include <malloc.h>
#include <mem.h>
#include <unistd.h>

/** Internal magic value for a map consistency check. */
#define INT_MAP_MAGIC_VALUE		0x11223344

/** Internal magic value for an item consistency check. */
#define INT_MAP_ITEM_MAGIC_VALUE	0x55667788

/** Generic destructor function pointer. */
#define DTOR_T(identifier) \
	void (*identifier)(const void *)

/** Integer to generic type map declaration.
 *
 * @param[in] name	Name of the map.
 * @param[in] type	Inner object type.
 */
#define INT_MAP_DECLARE(name, type) \
	typedef	struct name name##_t; \
	typedef	struct name##_item name##_item_t; \
	\
	struct	name##_item { \
		int key; \
		type *value; \
		int magic; \
	}; \
	\
	struct	name { \
		int size; \
		int next; \
		name##_item_t *items; \
		int magic; \
	}; \
	\
	int name##_add(name##_t *, int, type *); \
	void name##_clear(name##_t *, DTOR_T()); \
	int name##_count(name##_t *); \
	void name##_destroy(name##_t *, DTOR_T()); \
	void name##_exclude(name##_t *, int, DTOR_T()); \
	void name##_exclude_index(name##_t *, int, DTOR_T()); \
	type *name##_find(name##_t *, int); \
	int name##_update(name##_t *, int, int); \
	type *name##_get_index(name##_t *, int); \
	int name##_initialize(name##_t *); \
	int name##_is_valid(name##_t *); \
	void name##_item_destroy(name##_item_t *, DTOR_T()); \
	int name##_item_is_valid(name##_item_t *);

/** Integer to generic type map implementation.
 *
 * Should follow declaration with the same parameters.
 *
 * @param[in] name	Name of the map.
 * @param[in] type	Inner object type.
 */
#define INT_MAP_IMPLEMENT(name, type) \
	int name##_add(name##_t *map, int key, type *value) \
	{ \
		if (name##_is_valid(map)) { \
			if (map->next == (map->size - 1)) { \
				name##_item_t *tmp; \
				tmp = (name##_item_t *) realloc(map->items, \
				    sizeof(name##_item_t) * 2 * map->size); \
				if (!tmp) \
					return ENOMEM; \
				map->size *= 2; \
				map->items = tmp; \
			} \
			map->items[map->next].key = key; \
			map->items[map->next].value = value; \
			map->items[map->next].magic = INT_MAP_ITEM_MAGIC_VALUE; \
			++map->next; \
			map->items[map->next].magic = 0; \
			return map->next - 1; \
		} \
		return EINVAL; \
	} \
	\
	void name##_clear(name##_t *map, DTOR_T(dtor)) \
	{ \
		if (name##_is_valid(map)) { \
			int index; \
			for (index = 0; index < map->next; ++index) { \
				if (name##_item_is_valid(&map->items[index])) { \
					name##_item_destroy( \
					    &map->items[index], dtor); \
				} \
			} \
			map->next = 0; \
			map->items[map->next].magic = 0; \
		} \
	} \
	\
	int name##_count(name##_t *map) \
	{ \
		return name##_is_valid(map) ? map->next : -1; \
	} \
	\
	void name##_destroy(name##_t *map, DTOR_T(dtor)) \
	{ \
		if (name##_is_valid(map)) { \
			int index; \
			map->magic = 0; \
			for (index = 0; index < map->next; ++index) { \
				if (name##_item_is_valid(&map->items[index])) { \
					name##_item_destroy( \
					    &map->items[index], dtor); \
				} \
			} \
			free(map->items); \
		} \
	} \
	\
	void name##_exclude(name##_t *map, int key, DTOR_T(dtor)) \
	{ \
		if (name##_is_valid(map)) { \
			int index; \
			for (index = 0; index < map->next; ++index) { \
				if (name##_item_is_valid(&map->items[index]) && \
				    (map->items[index].key == key)) { \
					name##_item_destroy( \
					    &map->items[index], dtor); \
				} \
			} \
		} \
	} \
	\
	void name##_exclude_index(name##_t *map, int index, DTOR_T(dtor)) \
	{ \
		if (name##_is_valid(map) && (index >= 0) && \
		    (index < map->next) && \
		    name##_item_is_valid(&map->items[index])) { \
			name##_item_destroy(&map->items[index], dtor); \
		} \
	} \
	\
	type *name##_find(name##_t *map, int key) \
	{ \
		if (name##_is_valid(map)) { \
			int index; \
			for (index = 0; index < map->next; ++index) { \
				if (name##_item_is_valid(&map->items[index]) && \
				    (map->items[index].key == key)) { \
					return map->items[index].value; \
				} \
			} \
		} \
		return NULL; \
	} \
	\
	int name##_update(name##_t *map, int key, int new_key) \
	{ \
		if (name##_is_valid(map)) { \
			int index; \
			for (index = 0; index < map->next; ++index) { \
				if (name##_item_is_valid(&map->items[index])) { \
					if (map->items[index].key == new_key) \
						return EEXIST; \
					if (map->items[index].key == key) { \
						map->items[index].key = \
						    new_key; \
						return EOK; \
					} \
				} \
			} \
		} \
		return ENOENT; \
	} \
	\
	type *name##_get_index(name##_t *map, int index) \
	{ \
		if (name##_is_valid(map) && (index >= 0) && \
		    (index < map->next) && \
		    name##_item_is_valid(&map->items[index])) { \
			return map->items[index].value; \
		} \
		return NULL; \
	} \
	\
	int name##_initialize(name##_t *map) \
	{ \
		if (!map) \
			return EINVAL; \
		map->size = 2; \
		map->next = 0; \
		map->items = (name##_item_t *) malloc(sizeof(name##_item_t) * \
		    map->size); \
		if (!map->items) \
			return ENOMEM; \
		map->items[map->next].magic = 0; \
		map->magic = INT_MAP_MAGIC_VALUE; \
		return EOK; \
	} \
	\
	int name##_is_valid(name##_t *map) \
	{ \
		return map && (map->magic == INT_MAP_MAGIC_VALUE); \
	} \
	\
	void name##_item_destroy(name##_item_t *item, DTOR_T(dtor)) \
	{ \
		if (name##_item_is_valid(item)) { \
			item->magic = 0; \
			if (item->value) { \
				if (dtor) \
					dtor(item->value); \
				item->value = NULL; \
			} \
		} \
	} \
	\
	int name##_item_is_valid(name##_item_t *item) \
	{ \
		return item && (item->magic == INT_MAP_ITEM_MAGIC_VALUE); \
	}

#endif

/** @}
 */