/* -*- mode: c++; c-file-style: raknet; tab-always-indent: nil; -*- */
/**
 * @file HuffmanEncodingTreeFactory.h
 *
 * Copyright (c) 2003, Rakkarsoft LLC and Kevin Jenkins
 * 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.
 *     * Neither the name of the <organization> nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 <COPYRIGHT HOLDER> 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.
 */

#ifndef __HUFFMAN_ENCODING_TREE_FACTORY
#define __HUFFMAN_ENCODING_TREE_FACTORY

class HuffmanEncodingTree;

/**
 * This generates a special case of the huffman encoding tree with 8 bit keys
 */

class HuffmanEncodingTreeFactory
{

public:
	/**
	 * Default Constructor
	 */
	HuffmanEncodingTreeFactory();
	/**
	 * Reset the frequency table. You don't need to call this unless you want to reuse the class for a new tree
	 */
	void Reset( void );
	/**
	 * Pass an array of bytes to this to add those elements to the frequency table
	 * @param array the data to insert into the frequency table 
	 * @param size the size of the data to insert 
	 */
	void AddToFrequencyTable( unsigned char *array, int size );
	/**
	 * Copies the frequency table to the array passed
	 * Retrieve the frequency table 
	 * @param _frequency The frequency table used currently
	 */
	void GetFrequencyTable( unsigned int _frequency[ 256 ] );
	/**
	 * Returns the frequency table as a pointer
	 * @return the address of the frenquency table 
	 */
	unsigned int * GetFrequencyTable( void );
	/**
	 * Generate a HuffmanEncodingTree.
	 * You can also use GetFrequencyTable and GenerateFromFrequencyTable in the tree itself
	 */
	HuffmanEncodingTree * GenerateTree( void );
	
private:
	/**
	 * 256 frequencies.  
	 */
	unsigned int frequency[ 256 ];
};

#endif
