/*
    This file is part of libcapwap.

    libcapwap is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    libcapwap is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with Foobar.  If not, see <http://www.gnu.org/licenses/>.

*/

/**
 * @file
 * @brief MAVL, Mini AVL Tree, 
 * Yet another AVL Tree implementation!
 */


/** 
 * @defgroup MavlFunctions MAVL Functions
 * @{
 */


#ifndef __MAVL_H
#define __MAVL_H

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

#include <stdint.h>

/** Maximum AVL Tree depth. 
    The number of nodes is calculated by 2^depth.
    So a value of 32 should be enough for around 4 
    billion nodes. */
#define MAVL_MAX_DEPTH	32

/**
 * Defines the structure of an AVL Node.
 */
struct mavlnode {
	void *data;
	struct mavlnode *left;
	struct mavlnode *right;
	int bal;
};

/**
 * AVL Tree
 */ 
struct mavl {
	/** Pointer to root node */
	struct mavlnode *root;
	/** Compare function */
	int (*cmp) (const void *, const void *);
	/** Delete element function */
	void (*del) (void *);
	/** Number of elements currently stored in the tree */
	int count;
};

/** 
 * MAVL AVL Tree type
 */ 
typedef struct mavl * mavl_t;


//extern void mavlnode_destroy(struct mavl *t, struct mavlnode *n);

struct mavl *mavl_create(int (*cmp) (const void *, const void *),
			       void (*del) (void *));
//void mavl_destroy(struct mavl *t);
void mavlnode_destroy(struct mavl *t, struct mavlnode *n);

void mavl_del_all(struct mavl *t);
void *mavl_del(struct mavl *t, void *data);
void *mavl_add(struct mavl *t, void *data);
void * mavl_get(struct mavl *t ,void *data);
struct mavlnode *mavl_get_node(struct mavl *t, void *data);
void mavl_merge(mavl_t m, mavl_t t);


extern int mavl_foreach_lr(struct mavlnode *n, int (*callback) (void *, void *),
			      void *cbpriv);
extern int mavl_foreach_rl(struct mavlnode *n, int (*callback) (void *, void *),
			      void *cbpriv);
int mavl_foreach_from_lr(struct mavl *t, struct mavlnode *n, void *data,
			    int (*callback) (void *, void *), void *cbpriv);


//extern void mavl_foreach(struct mavl *t, int (*callback)(void *,void*),void *cbpriv,int dir);

static inline void *mavl_replace_data(struct mavl *t, void *data, int len)
{
	void *df = mavl_get(t, data);
	if (!df)
		return NULL;
	memcpy(df, data, len);
	return df;
}

static inline void *mavl_replace(struct mavl *t,void *data){
	struct mavlnode * node = mavl_get_node(t,data);
	if (node){
		t->del(node->data);
		return node->data=data;	
	}
	return mavl_add(t,data);
}


static inline void mavl_destroy(struct mavl *t)
{
	mavl_del_all(t);
	free (t);
}




#define mavl_find(t,d) mavl_get(t,d)
#define mavl_insert(t,d) mavl_add(t,d)
//#define mavl_walk(t,dir) mavl_foreach(t,dir)

#define mavl_foreach_asc(t,cb,priv) mavl_foreach_lr((t)->root,cb,priv)
#define mavl_foreach_desc(t,cb,priv) mavl_foreach_rl((t)->root,cb,priv)

#define mavl_foreach_from_asc(t,d,cb,priv) mavl_foreach_from_lr(t,(t)->root,d,cb,priv);


struct mavliter{
	struct mavlnode *stack[MAVL_MAX_DEPTH*2];

	struct mavlnode *cur;
	int stack_ptr;
	struct mavlnode * root;
	int (*cmp) (const void *, const void *);

};
typedef struct mavliter mavliter_t;


void * mavliter_next(mavliter_t *i);

static inline void * mavliter_seek_set(struct mavliter *i)
{
	i->stack_ptr=0;
	i->cur=i->root;
	return mavliter_next(i);
}

/**
 * Init an AVL Tree Iterator.
 *
 * After initialization #mavliter_next would return the first element.
 * The behavior of #mavliter_get would still be undefined.
 * @param i AVL Iterator to initialize
 * @param t correspondending AVL Tree
 *
 * @See mavliter_t, 
 */
static inline void mavliter_init(mavliter_t *i, mavl_t t){
	i->root = t->root;
	i->stack_ptr=0;
	i->cmp=t->cmp;
}

	
/**
 * Get the element, where AVL Iterator currently is positioned.
 * @param i AVL Iterator
 * @return element or NULL if not found.
 */
static inline void * mavliter_get(mavliter_t *i){
	if(!i->cur)
		return NULL;
	return i->cur->data;	
}


extern void * mavliter_seek(mavliter_t *i,void *d);

/** 
 * Define a AVL Iterator Varialble and acciciate it with 
 * an AVL Tree.
 * @param i Name of Variable to define
 * @param t #mavl_t Tree to associate.
 */ 
#define MAVLITER_DEFINE(i,t)\
	mavliter_t i; mavliter_init(&i,t)



#define mavliter_foreach(i)\
	for (mavliter_seek_set(i); NULL != mavliter_get(i); mavliter_next(i))

#define mavliter_foreach_from(i,from)\
	for (mavliter_seek(i,from); NULL != mavliter_get(i); mavliter_next(i))

#define mavliter_foreach_asc(iter,val) \
	while(NULL != (val = mavliter_next(iter)))




typedef mavl_t mavl_conststr_t;
extern mavl_conststr_t mavl_create_conststr();




/*
static inline void *mavl_replace_data(struct mavl *t, void *data, int len)
{
	void *df = mavl_get(t, data);
	if (!df)
		return NULL;
	memcpy(df, data, len);
	return df;
}

static inline void *mavl_replace(struct mavl *t,void *data){
	struct mavlnode * node = mavl_get_node(t,data);
	if (node){
		t->del(node->data);
		return node->data=data;	
	}
	return mavl_add(t,data);
}
*/


	
/** @} */

#endif