/**********************************************************
*      See the LICENSE file for copyright infomation.     *
**********************************************************/

#pragma once

#ifdef __cplusplus
extern "C" {
#endif

/*  CONVENTIONS:  All data structures for red-black trees have the prefix */
/*                "rb_" to prevent name conflicts. */
/*                                                                      */
/*                Function names: Each word in a function name begins with */
/*                a capital letter.  An example funcntion name is  */
/*                CreateRedTree(a,b,c). Furthermore, each function name */
/*                should begin with a capital letter to easily distinguish */
/*                them from variables. */
/*                                                                     */
/*                Variable names: Each word in a variable name begins with */
/*                a capital letter EXCEPT the first letter of the variable */
/*                name.  For example, int newLongInt.  Global variables have */
/*                names beginning with "g".  An example of a global */
/*                variable name is gNewtonsConstant. */

typedef struct rb_red_blk_node {
  void* key;
  int red; /* if red=0 then the node is black */
  struct rb_red_blk_node* left;
  struct rb_red_blk_node* right;
  struct rb_red_blk_node* parent;
} rb_red_blk_node;


/* Compare(a,b) should return 1 if *a > *b, -1 if *a < *b, and 0 otherwise */
/* Destroy(a) takes a pointer to whatever key might be and frees it accordingly */
typedef struct rb_red_blk_tree {
  int (*Compare)(const void* a, const void* b); 
  void (*DestroyKey)(void* a);
  /*  A sentinel is used for root and for nil.  These sentinels are */
  /*  created when RBTreeCreate is caled.  root->left should always */
  /*  point to the node which is the root of the tree.  nil points to a */
  /*  node which should always be black but has aribtrary children and */
  /*  parent and no key.  The point of using these sentinels is so */
  /*  that the root and nil nodes do not require special cases in the code */
  rb_red_blk_node* root;             
  rb_red_blk_node* nil;              
} rb_red_blk_tree;

rb_red_blk_tree* RBTreeCreate(int  (*CompFunc)(const void*, const void*),
                              void (*DestFunc)(void *));
rb_red_blk_node *RBTreeInsert(rb_red_blk_tree *, void *key);
void RBDelete(rb_red_blk_tree* , rb_red_blk_node* );
void RBTreeDestroy(rb_red_blk_tree*);
rb_red_blk_node* TreePredecessor(rb_red_blk_tree*,rb_red_blk_node*);
rb_red_blk_node* TreeSuccessor(rb_red_blk_tree*,rb_red_blk_node*);
rb_red_blk_node* RBExactQuery(rb_red_blk_tree*, void*);

#ifdef __cplusplus
}
#endif