/*
 * Copyright (C) Ascensio System SIA, 2009-2026
 *
 * This program is a free software product. You can redistribute it and/or
 * modify it under the terms of the GNU Affero General Public License (AGPL)
 * version 3 as published by the Free Software Foundation, together with the
 * additional terms provided in the LICENSE file.
 *
 * This program is distributed WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. For
 * details, see the GNU AGPL at: https://www.gnu.org/licenses/agpl-3.0.html
 *
 * You can contact Ascensio System SIA by email at info@onlyoffice.com
 * or by postal mail at 20A-6 Ernesta Birznieka-Upisha Street, Riga,
 * LV-1050, Latvia, European Union.
 *
 * The interactive user interfaces in modified versions of the Program
 * are required to display Appropriate Legal Notices in accordance with
 * Section 5 of the GNU AGPL version 3.
 *
 * No trademark rights are granted under this License.
 *
 * All non-code elements of the Product, including illustrations,
 * icon sets, and technical writing content, are licensed under the
 * Creative Commons Attribution-ShareAlike 4.0 International License:
 * https://creativecommons.org/licenses/by-sa/4.0/legalcode
 *
 * This license applies only to such non-code elements and does not
 * modify or replace the licensing terms applicable to the Program's
 * source code, which remains licensed under the GNU Affero General
 * Public License v3.
 *
 * SPDX-License-Identifier: AGPL-3.0-only
 */
#pragma once

#include "IBinaryReader.h"
#include "../Common/Base/FormatUtils.h"
#include "../../Common/3dParty/pole/pole.h"
#include "../../OOXML/Base/Base.h"

class VirtualStreamReader : public IBinaryReader
{
public:
	VirtualStreamReader (POLE::Stream* _stream, ULONG _position , int _nWordVersion);
	virtual ~VirtualStreamReader();

	virtual unsigned short ReadUInt16();
	virtual short ReadInt16();

	virtual int ReadInt32();
	virtual unsigned int ReadUInt32();

	virtual unsigned char ReadByte();
	virtual unsigned char* ReadBytes( unsigned int count, bool isResultNeeded );

	virtual unsigned long GetPosition() const;
	virtual unsigned long GetSize() const;
	virtual int Seek( int offset, int origin );

	std::wstring ReadXst();

	/// Read a length prefixed Unicode string from the given stream.
	/// The string must have the following structure:
	/// unsigned char 1 - 4: Character count (cch)
	/// unsigned char 5 - (cch*2)+4: Unicode characters terminated by \0
	std::wstring ReadLengthPrefixedUnicodeString();

	/// Read a length prefixed ANSI string from the given stream.
	/// The string must have the following structure:
	/// unsigned char 1-4: Character count (cch)
	/// unsigned char 5-cch+4:   ANSI characters terminated by \0
	std::wstring ReadLengthPrefixedAnsiString(unsigned int max_size);

	int			nWordVersion;

private:

	POLE::uint64			position;
	POLE::Stream*			stream;
};