/*
 * (c) Copyright Ascensio System SIA 2010-2023
 *
 * 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. In accordance with
 * Section 7(a) of the GNU AGPL its Section 15 shall be amended to the effect
 * that Ascensio System SIA expressly excludes the warranty of non-infringement
 * of any third-party rights.
 *
 * 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: http://www.gnu.org/licenses/agpl-3.0.html
 *
 * You can contact Ascensio System SIA at 20A-6 Ernesta Birznieka-Upish
 * street, Riga, Latvia, EU, LV-1050.
 *
 * The  interactive user interfaces in modified source and object code versions
 * of the Program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU AGPL version 3.
 *
 * Pursuant to Section 7(b) of the License you must retain the original Product
 * logo when distributing the program. Pursuant to Section 7(e) we decline to
 * grant you any rights under trademark law for use of our trademarks.
 *
 * All the Product's GUI elements, including illustrations and icon sets, as
 * well as technical writing content are licensed under the terms of the
 * Creative Commons Attribution-ShareAlike 4.0 International. See the License
 * terms at http://creativecommons.org/licenses/by-sa/4.0/legalcode
 *
 */

#include "PieceDescriptor.h"

namespace DocFileFormat
{	
	PieceDescriptor::PieceDescriptor(unsigned char *bytes, unsigned int size, int code_page_) : fc(0), code_page(code_page_), cpStart(0), cpEnd(0)
	{
		if (8 == size)
		{
			//get the fc value
			unsigned int fcValue = FormatUtils::BytesToUInt32(bytes, 2, size);

			//get the flag
			bool flag = FormatUtils::BitmaskToBool((int)fcValue, 0x40000000);

			//delete the flag
			fcValue = fcValue & 0xBFFFFFFF;

			//find encoding and offset
			if (flag)
			{
				code_page = ENCODING_WINDOWS_1250;
				this->fc = (unsigned int)( fcValue / 2 );
			}
			else
			{
				code_page = (code_page == ENCODING_WINDOWS_1250 ? ENCODING_UTF16 : code_page_);
				this->fc = fcValue;
			}
		}
	}
}