/*
 * This file is a part of Pcompress, a chunked parallel multi-
 * algorithm lossless compression and decompression program.
 *
 * Copyright (C) 2012-2013 Moinak Ghosh. All rights reserved.
 * Use is subject to license terms.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 3 of the License, or (at your option) any later version.
 *
 * This program 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this program.
 * If not, see <http://www.gnu.org/licenses/>.
 *
 * moinakg@gmail.com, http://moinakg.wordpress.com/
 */

/*
 * Dict filter for text files. Adapted from Public Domain sources
 * of Fu Siyuan's CSC 3.2 archiver.
 */

#ifndef _FILTERS_H
#define _FILTERS_H

#include <utils.h>

#include "Common.h"
#define MAX_WORDTREE_NODE_NUM 300 //Enough now!

class DictFilter
{
public:
	~DictFilter();
	DictFilter();

	u32 Forward_Dict(u8 *src, u32 size, u8 *dst, u32 *dstsize);
	void Inverse_Dict(u8 *src, u32 size, u8 *dst, u32 *dstsize);

private:
	typedef struct
	{
		u32 next[26];
		u8 symbol;
	} CTreeNode;
	CTreeNode wordTree[MAX_WORDTREE_NODE_NUM];
	u32 nodeMum;
	u8 maxSymbol;
	//Used for DICT transformer. Words are stored in trees.

	u32 wordIndex[256];
	//Used for DICT untransformer.choose words by symbols.
	void MakeWordTree();  //Init the DICT transformer

	u32 x0,x1;
	u32 i,k;
};

#ifdef  __cplusplus
extern "C" {
#endif

void *new_dict_context();
void delete_dict_context(void *dict_ctx);

int dict_encode(void *dict_ctx, uchar_t *from, uint64_t fromlen, uchar_t *to, uint64_t *dstlen);
int dict_decode(void *dict_ctx, uchar_t *from, uint64_t fromlen, uchar_t *to, uint64_t *dstlen);

#ifdef  __cplusplus
}
#endif

#endif