/***************************************************************************
 *   Copyright (C) 2008 by Keith Rusler   *
 *   [email protected]   *
 *                                                                         *
 *   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 "MSNSocket.h"

namespace MSNP
{
MSNSocket::MSNSocket ( QObject *parent )
		: QObject ( parent )
{
	m_state = MSNSocket::Unknown;
	m_buffer.clear();
	m_blocksize = 0;
	m_socket = new QTcpSocket;

	QObject::connect ( m_socket, SIGNAL ( readyRead() ), this, SLOT ( readCommand() ) );
	QObject::connect ( m_socket, SIGNAL ( stateChanged ( QAbstractSocket::SocketState ) ),
					   this, SLOT ( socketStateChanged ( QAbstractSocket::SocketState ) ) );
	QObject::connect ( m_socket, SIGNAL ( error ( QAbstractSocket::SocketError ) ),
					   this, SLOT ( socketError ( QAbstractSocket::SocketError ) ) );
}

MSNSocket::~MSNSocket()
{
}

void
MSNSocket::connect ( const QString& address, const quint16 port )
{
	m_socket->connectToHost ( address, port );
}

void
MSNSocket::disconnect()
{
	m_socket->abort();
}

bool
MSNSocket::sendCommand ( QString command )
{
	if ( command.isEmpty() ) {
		return false;
	}

	bool status = false;
	m_unmodifiedCommand = command;

	if ( m_state == MSNSocket::Sending ) {
		// arse the command string.
		m_command.parseCommand ( command, MSNCommand::Send );
		// check to see if the lengths are the same to ensure the command was sent successfully.
		status = ( m_socket->write ( m_command.toString().toUtf8() ) == m_command.toString().toUtf8().size() );
		qDebug() << "[SENT] " << m_command.toString();
		// set the state to a new one so receiving a command is possible.
		m_state = MSNSocket::Receiving;
		// emit the state for derived classes.
		emit socketState ( m_state );
	}
	return status;
}

void
MSNSocket::processData ( )
{
	// check to see if the buffer is finished.
	if ( !finishedBuffer ( ) ) {
		m_command.parseCommand ( m_buffer, MSNCommand::Read );
		if ( m_command.getError() != "No error" ) {
			emit errorState ( m_command.getErrorNumber(), m_command.getError() );
			qDebug() << QString ( "Error num: %1 Error String: %2" ).arg ( m_command.getErrorNumber() ).arg ( m_command.getError() );
		} else {
			qDebug() << "[RECV] " << m_command.toString();
			m_state = MSNSocket::Sending;
			emit socketState ( m_state );
			emit parseCommand ( m_command );
		}
		m_state = MSNSocket::Receiving;
		emit socketState ( m_state );
	}
}

void
MSNSocket::readCommand()
{
	// make sure the command isn't ready  if sending is still performing.
	if ( m_state == MSNSocket::Sending ) {
		return;
	}

	// Now we can send a command.
	if ( m_state == MSNSocket::Receiving ) {
		// Get the available bytes.
		qint32 available = m_socket->bytesAvailable();

		// read only the available size.
		m_buffer = m_socket->read ( available );

		// check to see if the buffer is empty.
		if ( m_buffer.isEmpty() ) {
			qDebug() << "readCommand()::m_buffer is empty";
		} else if ( available ) {
			// check to see if the buffer size contains as much data as was available.
			if ( m_buffer.size() != available ) {
				qDebug() << QString ( "Reported %1 but only read %2" ).arg ( available ).arg ( m_buffer.size() );
			}
			// process the data that was available.
			processData ( );
		}
	}
}

MSNCommand&
MSNSocket::getLastCommand()
{
	return m_command;
}

MSNSocket::ConnectionState
MSNSocket::getState() const
{
	return m_state;
}

void
MSNSocket::readIntoBlock ( qint32 blocksize, qint32 beg )
{
	if ( m_blocksize ) {
		return;
	}

	m_blocksize = blocksize;
	m_blockBeg = beg;

	finishedBuffer ( );
}

void
MSNSocket::socketStateChanged ( QAbstractSocket::SocketState state )
{
	switch ( state ) {
		case QAbstractSocket::ConnectingState:
			qDebug() << "[STATE] " << state;
			m_state = MSNSocket::Connecting;
			emit socketState ( m_state );
			break;
		case QAbstractSocket::ConnectedState:
			qDebug() << "[STATE] " << state;
			m_state = MSNSocket::Connected;
			emit socketState ( m_state );
			m_state = MSNSocket::Sending;
			emit socketState ( m_state );
			sendCommand ( m_unmodifiedCommand );
			break;
		case QAbstractSocket::ClosingState:
			qDebug() << "[STATE] " << state;
			m_state = MSNSocket::Disconnecting;
			emit socketState ( m_state );
			break;
		case QAbstractSocket::UnconnectedState:
			qDebug() << "[STATE] " << state;
			m_state = MSNSocket::Disconnected;
			emit socketState ( m_state );
			break;
		default:
			qDebug() << "[STATE] " << state;
			break;
	}
}

void
MSNSocket::socketError ( QAbstractSocket::SocketError error )
{
	qDebug() << "[ERROR] " << error;
}

bool
MSNSocket::finishedBuffer ( )
{
	if ( !m_blocksize ) {
		return false;
	}

	if ( m_blockBuffer.size() != m_blocksize ) {
		qDebug() << QString ( "Waiting for data: Received: %1 Total: %2 / %3" ).arg ( m_socket->bytesAvailable() ).arg ( m_blocksize - m_blockBuffer.size() ).arg ( m_blocksize );
		m_blockBuffer.append ( m_buffer );

		if ( m_blockBuffer.size() >= m_blocksize ) {
			QByteArray block;

			for ( int i = 0; i < m_blocksize; ++i ) {
				block.append ( m_blockBuffer.data() [m_blockBeg + i] );
			}

			m_blockBuffer.remove ( 0, m_blocksize + m_blockBeg );

			m_command.parseCommand ( m_blockBuffer );

			qDebug() << "[RECV] " << m_command.toString();

			emit parseCommand ( m_command );
			emit readBlock ( block );

			m_blocksize = 0;
			m_blockBuffer.clear();
		}
		return true;
	}
	return false;
}

} // MSNP namespace.