/***************************************************************************
 *   Copyright (C) 2008 by Volker Lanz <vl@fidra.de>                       *
 *                                                                         *
 *   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            *
 ***************************************************************************/

#include "fs/ext2.h"

#include "util/externalcommand.h"
#include "util/capacity.h"

#include <QString>
#include <QRegExp>

namespace FS
{
	FileSystem::SupportType ext2::m_GetUsed = FileSystem::SupportNone;
	FileSystem::SupportType ext2::m_GetLabel = FileSystem::SupportNone;
	FileSystem::SupportType ext2::m_Create = FileSystem::SupportNone;
	FileSystem::SupportType ext2::m_Grow = FileSystem::SupportNone;
	FileSystem::SupportType ext2::m_Shrink = FileSystem::SupportNone;
	FileSystem::SupportType ext2::m_Move = FileSystem::SupportNone;
	FileSystem::SupportType ext2::m_Check = FileSystem::SupportNone;
	FileSystem::SupportType ext2::m_Copy = FileSystem::SupportNone;
	FileSystem::SupportType ext2::m_Backup = FileSystem::SupportNone;
	FileSystem::SupportType ext2::m_SetLabel = FileSystem::SupportNone;
	FileSystem::SupportType ext2::m_UpdateUUID = FileSystem::SupportNone;

	ext2::ext2(qint64 firstsector, qint64 lastsector, qint64 sectorsused, const QString& label, FileSystem::Type t) :
		FileSystem(firstsector, lastsector, sectorsused, label, t)
	{
	}

	void ext2::init()
	{
		m_GetUsed = findExternal("dumpe2fs") ? SupportExternal : SupportNone;
		m_SetLabel = m_GetLabel = findExternal("e2label") ? SupportExternal : SupportNone;
		m_Create = findExternal("mkfs.ext2") ? SupportExternal : SupportNone;
		m_Check = findExternal("e2fsck", QStringList() << "-V") ? SupportExternal : SupportNone;
		m_UpdateUUID = findExternal("tune2fs") ? SupportExternal : SupportNone;
		m_Grow = (m_Check != SupportNone && findExternal("resize2fs")) ? SupportExternal : SupportNone;
		m_Shrink = m_GetUsed != SupportNone ? SupportExternal : SupportNone;
		m_Copy = (m_Check != SupportNone) ? SupportInternal : SupportNone;
		m_Move = (m_Check != SupportNone) ? SupportInternal : SupportNone;
		m_Backup = SupportInternal;
	}

	qint64 ext2::maxCapacity() const
	{
		 return Capacity::unitFactor(Capacity::Byte, Capacity::EiB);
	}
	
	qint64 ext2::readUsedCapacity(const QString& deviceNode) const
	{
		ExternalCommand cmd("dumpe2fs", QStringList() << "-h" << deviceNode);

		if (cmd.run())
		{
			qint64 blockCount = -1;
			QRegExp rxBlockCount("Block count:\\s*(\\d+)");

			if (rxBlockCount.indexIn(cmd.output()) != -1)
				blockCount = rxBlockCount.cap(1).toLongLong();
			
			qint64 reservedBlocks = -1;
			QRegExp rxReservedBlocks("Reserved block count:\\s*(\\d+)");

			if (rxReservedBlocks.indexIn(cmd.output()) != -1)
				reservedBlocks = rxReservedBlocks.cap(1).toLongLong();
			
			qint64 numFreeBlocks = -1;
			QRegExp rxFreeBlocks("Free blocks:\\s*(\\d+)");

			if (rxFreeBlocks.indexIn(cmd.output()) != -1)
				numFreeBlocks = rxFreeBlocks.cap(1).toLongLong();

			qint64 blockSize = -1;
			QRegExp rxBlockSize("Block size:\\s*(\\d+)");

			if (rxBlockSize.indexIn(cmd.output()) != -1)
				blockSize = rxBlockSize.cap(1).toLongLong();

			if (blockCount > -1 && reservedBlocks > -1 && numFreeBlocks > -1 && blockSize > -1)
				return (blockCount - reservedBlocks - numFreeBlocks) * blockSize;
		}

		return -1;
	}

	QString ext2::readLabel(const QString& deviceNode) const
	{
		ExternalCommand cmd("e2label", QStringList() << deviceNode);
		return cmd.run() ? cmd.output().simplified() : QString();
	}

	bool ext2::check(Report& report, const QString& deviceNode) const
	{
		ExternalCommand cmd(report, "e2fsck", QStringList() << "-f" << "-y" << "-v" << deviceNode);
		return cmd.run(-1) && (cmd.exitCode() == 0 || cmd.exitCode() == 1 || cmd.exitCode() == 2 || cmd.exitCode() == 256);
	}

	bool ext2::create(Report& report, const QString& deviceNode) const
	{
		return ExternalCommand(report, "mkfs.ext2", QStringList() << deviceNode).run(-1);
	}

	bool ext2::resize(Report& report, const QString& deviceNode, qint64 length) const
	{
		const QString len = QString::number(length / 512) + 's';
		ExternalCommand cmd(report, "resize2fs", QStringList() << deviceNode << len);
 		return cmd.run(-1) && cmd.exitCode() == 0;
	}

	bool ext2::writeLabel(Report& report, const QString& deviceNode, const QString& newLabel)
	{
		return ExternalCommand(report, "e2label", QStringList() << deviceNode << newLabel).run(-1);
	}

	bool ext2::updateUUID(Report& report, const QString& deviceNode) const
	{
		return ExternalCommand(report, "tune2fs", QStringList() << "-U" << "random" << deviceNode).run(-1);
	}
}