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/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program 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 2
* 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 General Public License for more details.

* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/

#ifndef ZVISION_LZSS_STREAM_H
#define ZVISION_LZSS_STREAM_H

#include "common/types.h"
#include "common/stream.h"
#include "common/array.h"

namespace Common {
class SeekableReadStream;
}

namespace ZVision {

class LzssReadStream : public Common::ReadStream {
public:
	/**
	 * A class that decompresses LZSS data and implements ReadStream for easy access 
	 * to the decompiled data.
	 *
	 * @param source              The source data
	 */
	LzssReadStream(Common::SeekableReadStream *source);

public:
	static const uint32 _npos = 0xFFFFFFFFu;
	static const uint16 _blockSize = 0x1000u;

private:
	Common::SeekableReadStream *_source;
	char _window[_blockSize];
	uint16 _windowCursor;
	bool _eosFlag;

public:
	bool eos() const;
	uint32 read(void *dataPtr, uint32 dataSize);

private:
	/**
	 * Decompress the next <numberOfBytes> from the source stream. Or until EOS
	 *
	 * @param numberOfBytes    How many bytes to decompress. This is a count of source bytes, not destination bytes
	 */
	uint32 decompressBytes(byte* destination, uint32 numberOfBytes);
};

}

#endif