/***************************************************************************
 *   Copyright (C) 2007 by Torben Nielsen   *
 *   torben@t-hoerup.dk   *
 *                                                                         *
 *   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.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/
#include "acpiparser.h"

#include <iostream>
#include <fstream>
#include <sstream>
#include <stdexcept>
#include <stdlib.h>

AcpiParser::AcpiParser()
{
	mNumstates = 0;
	mCurrentState = 0;
}


AcpiParser::~AcpiParser()
{
}

void AcpiParser::ReadAcpiFile()
{
	char buffer[1024];
	std::ifstream in;
	
	in.open("/proc/acpi/processor/CPU0/throttling");
	if  (!in)
		throw std::runtime_error("Could not open file");
	
	int linecounter = 0;
	mStateDescriptions.clear();
	
	while (! in.eof() )
	{
		in.getline(buffer,1024);
		std::string line(buffer);
		linecounter++;
		
		unsigned int pos = line.rfind(' ');
		if (pos == std::string::npos)
			continue;
		pos++;
		
		std::string value = line.substr(pos, line.size() - pos);
		//std::cout << "Value: (" << linecounter << ") = " << value << std::endl;
		
		switch (linecounter)
		{
			case 1:
				mNumstates = atoi(value.c_str());
				break;
			case 2:
			{
				std::string tmp = value.substr(1, value.size() -1);
				mCurrentState = atoi(tmp.c_str() );
				//std::cout << "tmp: >" << tmp << "< = " << std::endl;
				break;
			}
			case 3:
				break;
			default:
				mStateDescriptions.push_back( value );				
		}
	}
	
	in.close();
	//std::cout << "Current state:" << mCurrentState <<std::endl;
	//std::cout << "Numstates:" << mNumstates << std::endl;
}


int AcpiParser::GetCurrentState()
{
    return mCurrentState;
}



int AcpiParser::GetStateCount()
{
    return mNumstates;
}


std::string AcpiParser::GetStateDescription(unsigned int stateNumber)
{
	if (stateNumber >= mStateDescriptions.size() )
		return "";
	
	return mStateDescriptions[stateNumber];
}



void AcpiParser::SetState(int newState)
{
	if (newState > mNumstates)
		throw std::invalid_argument("newState too small");
	
	std::ofstream out;
	out.open("/proc/acpi/processor/CPU0/throttling");
	
	if (!out)
		throw std::runtime_error("Could not open file");
	

	std::stringstream buf;
	buf << newState << "\n";
	out << buf.str();
	out.close();
}