path: root/src/server/mainwindow/mainwindow.cpp

/*
 # Copyright (c) 2009 - OpenSLX Project, Computer Center University of Freiburg
 #
 # This program is free software distributed under the GPL version 2.
 # See http://openslx.org/COPYING
 #
 # If you have any feedback please consult http://openslx.org/feedback and
 # send your suggestions, praise, or complaints to feedback@openslx.org
 #
 # General information about OpenSLX can be found at http://openslx.org/
 # -----------------------------------------------------------------------------
 # mainWindow.cpp
 This is the Main class for the pvsManager. The GUI is constructed here.
 # -----------------------------------------------------------------------------
 */
// Self
#include "mainwindow.h"
// QT stuff
#include <QtGui>
#include <QFileDialog>
// Other custom UI elements
#include "../clicklabel/clicklabel.h"
#include "../sessionnamewindow/sessionnamewindow.h"
#include "../connectionframe/connectionframe.h"
// Network
#include "../net/listenserver.h"
#include "../net/client.h"
#include "../net/discoverylistener.h"
#include "../../shared/networkmessage.h"
#include "../net/filedownloader.h"
// Others
#include "../../shared/settings.h"
#include "../util/util.h"
#include "../util/global.h"
// Auto-generated ui class
#include "ui_mainwindow.h"

/**
 * Initialize MainWindow and ListenServer.
 * @param ipListUrl
 * @param parent
 */
MainWindow::MainWindow(QString ipListUrl, QWidget* parent) :
	QMainWindow(parent), ui(new Ui::MainWindow), _tbIconSize(24), _tbArea(Qt::LeftToolBarArea)
{
	_sessionNameWindow = new SessionNameWindow(this);
	ui->setupUi(this);

	Global::setSessionName();

	//conWin = new ConnectionWindow(ui->widget);
	//ui->VconWinLayout->addWidget(conWin);
	//conList = new ConnectionList(ui->ClWidget);
	//ui->ClientGLayout->addWidget(conList);

	// Show only session name label, not textbox
	_sessionNameLabel = new ClickLabel(this);
	ui->mainLayout->addWidget(_sessionNameLabel);

	ui->frmRoom->setStyleSheet("background-color:#444");

	// toolbar and actions in pvsmgr
	ui->action_Exit->setStatusTip(tr("Exit"));
	ui->action_Lock->setStatusTip(tr("Lock or Unlock all Clients"));

	// Initialize FileDownloader.
	if (!ipListUrl.isEmpty())
	{
		_fileDownloader.connectSlot(this, SLOT(onTutorListDownloaded(QByteArray&)));
		_fileDownloader.downloadFile(QUrl(ipListUrl));
	}

	// Close button in tool bar
	connect(ui->action_Exit, SIGNAL(triggered()), this, SLOT(onButtonExit()));
	connect(ui->action_BroadcastScreen, SIGNAL(triggered()), this, SLOT(onButtonStudentToAll()));
	connect(ui->action_TutorToAll, SIGNAL(triggered()), this, SLOT(onButtonTutorToAll()));
	connect(ui->action_StudentToTutor, SIGNAL(triggered()), this, SLOT(onButtonStudentToTutor()));
	connect(ui->action_TutorToStudent, SIGNAL(triggered()), this, SLOT(onButtonTutorToStudent()));
	connect(ui->action_StopProjection, SIGNAL(triggered()), this, SLOT(onButtonStopProjection()));
	connect(ui->action_SetAsTutor, SIGNAL(triggered()), this, SLOT(onButtonSetAsTutor()));
	connect(ui->action_SetAsTutor, SIGNAL(triggered()), this, SLOT(onButtonStopProjection()));
	connect(ui->action_Lock, SIGNAL(toggled(bool)), this, SLOT(onButtonLock(bool)));

	/* Stuff for the button lock */
	_buttonLockTimer = new QTimer(this);
	_buttonLockTimer->setSingleShot(true);
	_buttonLockTimer->setInterval(_buttonBlockTime);
	// Disable the buttons if a button is clicked
	connect(ui->action_Lock, SIGNAL(triggered()),            this, SLOT(DisableButtons()));
	connect(ui->action_BroadcastScreen, SIGNAL(triggered()), this, SLOT(DisableButtons()));
	connect(ui->action_TutorToAll, SIGNAL(triggered()),      this, SLOT(DisableButtons()));
	connect(ui->action_StudentToTutor, SIGNAL(triggered()),  this, SLOT(DisableButtons()));
	connect(ui->action_TutorToStudent, SIGNAL(triggered()),  this, SLOT(DisableButtons()));
	connect(ui->action_StopProjection, SIGNAL(triggered()),  this, SLOT(DisableButtons()));
	// Start the timer a button is clicked
	connect(ui->action_Lock, SIGNAL(triggered()),            _buttonLockTimer, SLOT(start()));
	connect(ui->action_BroadcastScreen, SIGNAL(triggered()), _buttonLockTimer, SLOT(start()));
	connect(ui->action_TutorToAll, SIGNAL(triggered()),      _buttonLockTimer, SLOT(start()));
	connect(ui->action_StudentToTutor, SIGNAL(triggered()),  _buttonLockTimer, SLOT(start()));
	connect(ui->action_TutorToStudent, SIGNAL(triggered()),  _buttonLockTimer, SLOT(start()));
	connect(ui->action_StopProjection, SIGNAL(triggered()),  _buttonLockTimer, SLOT(start()));
	// Enable the buttons if the timer fires
	connect(_buttonLockTimer, SIGNAL(timeout()), this, SLOT(EnableButtons()));


	// Clicking the session name label shows the edit field for it
	connect(_sessionNameLabel, SIGNAL(clicked()), this, SLOT(onSessionNameClick()));
	// Listen to updates to the session name through the session name window
	connect(_sessionNameWindow, SIGNAL(updateSessionName()), this,
	   SLOT(onSessionNameUpdate()));

	setAttribute(Qt::WA_QuitOnClose);
	setUnifiedTitleAndToolBarOnMac(true);
	this->showMaximized(); // show the Mainwindow maximized

	_tileWidth = 10;
	_tileHeight = 10;

	_timerId = 0;
	_timerTimeout = 0;

	_listenServer = new ListenServer(CLIENT_PORT);
	connect(_listenServer, SIGNAL(newClient(Client*)), this, SLOT(onClientConnected(Client*)));
	_discoveryListener = new DiscoveryListener();

	// Finally
	this->onSessionNameUpdate();
	_timerId = startTimer(10);
	_timerTimeout = 8;
}

MainWindow::~MainWindow()
{
	_sessionNameLabel->deleteLater();
	delete ui;
}

/**
 * Place the frames at possible Position.
 * If current position out of range, place frame into next free cell.
 * @param frame
 */
void MainWindow::placeFrameInFreeSlot(ConnectionFrame* frame)
{
	// Get occupied cell of each frame and store status in an array
	const int elems = _tilesX * _tilesY;
	int currentIndex = 0;
	bool grid[elems];
	memset(grid, 0, sizeof(bool) * elems); // set everything to false
	for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
	{
		const QPoint &oldpos = (*it)->frameGeometry().topLeft();
		const int tx = oldpos.x() / _tileWidth;
		const int ty = oldpos.y() / _tileHeight;
		const int index = tx + ty * _tilesX;
		if (frame == *it)
		{
			// Current frame is the frame to place, remember its old index
			currentIndex = index;
			continue;
		}
		if (index < 0 || index >= elems)
		{
			// Current frame is out of bounds, place in top left corner
			qDebug("Move A");
			(*it)->move(0, 0);
			grid[0] = true;
			continue;
		}
		// Just mark cell as occupied in array
		grid[index] = true;
	}
	// Safety
	if (currentIndex < 0 || currentIndex >= elems)
		currentIndex = 0;
	// Now place in next free cell, start looking at current position of frame
	for (int i = 0; i < elems; ++i)
	{
		const int index = (i + currentIndex) % elems;
		if (grid[index])
			continue;
		const int x = (index % _tilesX) * _tileWidth;
		const int y = (index / _tilesX) * _tileHeight;
		//qDebug() << "Index=" << index << " i=" << i << " cI=" << currentIndex << " elems=" << elems << " x=" << x << " y=" << y;
		qDebug("Move B");
		frame->move(x, y);
		break;
	}
}

/**
 * Create new Frame.
 * Create new frame and add to current available frame list.
 * Also connect signals frameMoved() and clicked() with slots.
 * @return ConnectionFrame*
 */
ConnectionFrame* MainWindow::createFrame()
{
	// Allocate and resize
	ConnectionFrame *cf = new ConnectionFrame(ui->frmRoom, _tileWidth, _tileHeight);
	_clientFrames.append(cf);
	cf->show();
	connect(cf, SIGNAL(frameMoved(ConnectionFrame *)), this, SLOT(onPlaceFrame(ConnectionFrame *)));
	connect(cf, SIGNAL(clicked(ConnectionFrame *)), this, SLOT(onFrameClicked(ConnectionFrame *)));
	return cf;
}

/**
 * Load position.
 * @param settings
 * @param id
 * @param x
 * @param y
 * @return If loadPosition was successfull.
 */
bool MainWindow::loadPosition(QSettings& settings, const QString& id, int& x, int& y)
{
	settings.beginGroup("client_position");
	const QVariant retval(settings.value(id));
	settings.endGroup();
	if (retval.type() != QVariant::Point)
		return false;
	const QPoint point(retval.toPoint());
	x = point.x();
	y = point.y();
	return true;
}

/**
 * Save position of given connectionFrame.
 * @param cf
 */
void MainWindow::savePosition(ConnectionFrame *cf)
{
	Client *client = cf->client();
	if (client == NULL)
		return;
	QPoint pos(cf->pos().x() / _tileWidth, cf->pos().y() / _tileHeight);
	USER_SETTINGS(settings);
	settings.beginGroup("client_position");
	settings.setValue(client->computerId(), pos);
	settings.endGroup();
}

/*
 * Overridden methods
 */

/**
 * Handle closeEvent.
 * If user calls closing MainWindow, close, else ignore.
 * @param e
 */
void MainWindow::closeEvent(QCloseEvent* e)
{
	int ret = QMessageBox::question(this, "Test", "Exit?", 0, 1, 2);
	if (ret == 1)
		QApplication::exit(0);
	else
		e->ignore();
}

/**
 * Change Event.
 * @param e
 */
void MainWindow::changeEvent(QEvent* e)
{
	QMainWindow::changeEvent(e);
}

/**
 * Resize event.
 * @param e
 */
void MainWindow::resizeEvent(QResizeEvent* e)
{
	QMainWindow::resizeEvent(e);
	if (_timerId == 0)
	{
		_timerId = startTimer(5);
	}
	_timerTimeout = 8;
}

/**
 * Handle Mouse Release Event.
 * Check if click was inside the frame and if that is the case, set the selection of each connected
 * client to false.
 * @param e
 */
void MainWindow::mouseReleaseEvent(QMouseEvent* e)
{
	// Try to figure out if the user clicked inside the "room" frame
	// No idea if there is a more elegant way to do this without
	// sub-classing that frame and overriding its mouseReleaseEvent
	const QPoint pos(ui->frmRoom->mapFrom(this, e->pos()));
	if (pos.x() < 0 || pos.y() < 0)
		return;
	const QSize frame(ui->frmRoom->size());
	if (frame.width() > pos.x() && frame.height() > pos.y())
	{
		for (QList<ConnectionFrame*>::iterator it = _clientFrames.begin(); it != _clientFrames.end(); ++it)
		{
			(**it).setSelection(false);
		}
	}
}

/**
 * Handle Timer EventtimerEvent.
 * @param event
 */
void MainWindow::timerEvent(QTimerEvent* event)
{
	if (event->timerId() == _timerId)
	{
		_timerTimeout -= 1;
		if (_timerTimeout == 1)
		{
			// Move toolbar if necessary
			const int iconSize = this->size().width() / 30 + 14;
			const int barSpace = ui->toolBar->actions().size() * (iconSize + 8);
			const Qt::ToolBarArea area =
				(barSpace < this->size().height() ? Qt::LeftToolBarArea : Qt::TopToolBarArea);
			if (_tbIconSize != iconSize)
			{
				_tbIconSize = iconSize;
				ui->toolBar->setIconSize(QSize(iconSize, iconSize));
			}
			if (_tbArea != area)
			{
				_tbArea = area;
				this->addToolBar(area, ui->toolBar);
			}
			return;
		}
		// Kill timer when done
		if (_timerTimeout <= 0)
		{
			killTimer(_timerId);
			_timerId = 0;
			// Resize all connection windows
			if (ui->frmRoom->size().width() < 100 || ui->frmRoom->size().height() < 100 || _tilesX <= 0 || _tilesY <= 0)
				return;
			const int nw = ui->frmRoom->size().width() / _tilesX;
			const int nh = ui->frmRoom->size().height() / _tilesY;
			for (QList<ConnectionFrame*>::iterator it = _clientFrames.begin(); it != _clientFrames.end(); ++it)
			{
				const QPoint &oldpos = (*it)->frameGeometry().topLeft();
				qDebug("Move C");
				(*it)->move((oldpos.x() / _tileWidth) * nw, (oldpos.y() / _tileHeight) * nh);
				(*it)->setSize(nw, nh);
			}
			_tileWidth = nw;
			_tileHeight = nh;
		}
	}
	else
	{
		// Unknown timer ID, kill
		killTimer(event->timerId());
	}
}

/*
 * Slots
 */

/**
 * Extract information from downloaded tutorList.
 * Split downloaded file by new line and store ips in _tutorList.
 * @param tutorList
 */
void MainWindow::onTutorListDownloaded(QByteArray& tutorList)
{
	// qDebug() << tutorList;
	QString data = QString::fromUtf8(tutorList.constData(), tutorList.size());
	_tutorList = data.split(QRegExp("[\r\n]"),QString::SkipEmptyParts);
	qDebug() << _tutorList;
}

/**
 * Place Frame to from user specified position.
 * @param frame
 */
void MainWindow::onPlaceFrame(ConnectionFrame* frame)
{
	if (_tilesX <= 0 || _tilesY <= 0)
		return;
	const QPoint &p = frame->frameGeometry().center();
	const QSize &s = ui->frmRoom->geometry().size();
	int x = (p.x() / _tileWidth) * _tileWidth;
	int y = (p.y() / _tileHeight) * _tileHeight;
	if (x < 0)
		x = 0;
	else if (x > s.width() - _tileWidth)
		x = (_tilesX - 1) * _tileWidth;
	if (y < 0)
		y = 0;
	else if (y > s.height() - _tileHeight)
		y = (_tilesY - 1) * _tileHeight;
	qDebug("Move D");
	frame->move(x, y);
	savePosition(frame);
	const QPoint &newpos = frame->frameGeometry().topLeft();
	for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
	{
		if (*it == frame)
			continue;
		if ((*it)->frameGeometry().topLeft() == newpos)
		{
			placeFrameInFreeSlot(*it);
		}
	}
}

/**
 * Mark given frame after it was clicked on.
 * @param frame
 */
void MainWindow::onFrameClicked(ConnectionFrame* frame)
{
	for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
	{
		if (*it == frame)
			frame->setSelection(true);
		else
			(**it).setSelection(false);
	}
}

/**
 * Show session name, after it was clicked on.
 */
void MainWindow::onSessionNameClick()
{
	_sessionNameWindow->show(Global::sessionName());
}

/**
 * Update session name.
 */
void MainWindow::onSessionNameUpdate()
{
	_sessionNameLabel->setText(tr("Session Name: %1  [click to edit]").arg(Global::sessionName()));
}

/**
 * OnButtonSettings.
 */
void MainWindow::onButtonSettings()
{
	// Move to any free tile
	placeFrameInFreeSlot(createFrame());
}

/**
 * OnButtonChat.
 */
void MainWindow::onButtonChat()
{
	/*
	 for (QList<ConnectionFrame*>::iterator it = _clientFrames.begin(); it != _clientFrames.end(); ++it) {
	 (*it)->setSize(100 + qrand() % 200);
	 }
	 */
}

/**
 * Check if given client is valid.
 * And if that is the case return true.
 * @param client
 * @return If client is valid or not.
 */
bool MainWindow::isValidClient(Client* client)
{
	for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
	{
		Client *c = (**it).client();
		if (c == client)
			return true;
	}
	return false;
}

/**
 * Handle VNC settings for a projection from "from" to "to".
 * Check if projection source is active vnc client.
 * Check if projection is One --> Many or One --> One.
 * @param from
 * @param to
 */
void MainWindow::prepareForProjection(Client * const from, Client * const to)
{
	// Projection source is never allowed to be an active VNC viewer
	if (from->isActiveVncClient())
	{
		qDebug("From is active client, stopping...");
		from->stopVncClient();
	}
	from->setDesiredProjectionSource(0);

	if (to == NULL)
	{
		// One to many
		qDebug("One to many requested...");
		from->setProjectionSource(true);

		// Set desired projection source on all clients
		for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
		{
			Client *c = (**it).client();
			if (c == NULL || c->id() == from->id())
				continue; // Self or offline
			c->setDesiredProjectionSource(from->id());
		}

		if (from->isActiveVncServer())
		{
			// From is already active, if there is at least one active client, assume it is not
			// shutting down, so we can directly tell the new client to connect to it
			qDebug("Source is already running a VNC server....");
			for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
			{
				Client *c = (**it).client();
				if (c == NULL || c->id() == from->id())
					continue; // Self or offline
				if (c->currentProjectionSource() != from->id())
					continue; // Other client
				// Yep :-)
				qDebug("Reusing because of active client");
				this->onVncServerStateChange(from);
				return;
			}
			qDebug("But no active client found....");
		}
		// Could not take shortcut, (re)start VNC server on source
		qDebug("Starting VNC server on source machine");
		from->startVncServer();
		return;
	}

	// One to one is desired, figure out what to do with current client

	to->setProjectionSource(false);
	if (to->isActiveVncServer())
	{
		if (to->currentProjectionSource() == from->id())
			return; // Nothing to do
		to->stopVncServer();
	}
	to->setDesiredProjectionSource(from->id());

	if (from->isActiveVncServer())
	{
		// From is already active, if there is at least one active client, assume it is not
		// shutting down, so we can directly tell the new client to connect to it
		for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
		{
			Client *c = (**it).client();
			if (c == NULL || c->id() == from->id())
				continue;
			if (c->currentProjectionSource() != from->id())
				continue;
			// Yep :-)
			this->onVncServerStateChange(from);
			return;
		}
	}
	// Could not take shortcut, (re)start VNC server on source
	from->startVncServer();
}

/**
 * Button projection from one student to all the others.
 * First get which client is projectionSource and set this one as from.
 * Set projection source for all clients,except the selected one, to false.
 * Then call prepareForProjection(from, Null).
 */
void MainWindow::onButtonStudentToAll()
{
	Client *from = NULL;
	for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
	{
		Client *c = (**it).client();
		if (c == NULL)
			continue;
		if ((**it).selected())
			from = c;
		else
			c->setProjectionSource(false);
	}
	if (from == NULL)
		QMessageBox::critical(this,
			tr("Projection"),
			tr("No projection source selected.")
		);
	else
		prepareForProjection(from, NULL);
}

/**
 * Handle projection from one student to tutor.
 * Get the client to project from and get client, who is tutor, as to.
 * Call prepareForProjection(from, to).
 */
void MainWindow::onButtonStudentToTutor()
{
	Client *from = NULL;
	Client *to = NULL;
	for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
	{
		Client *c = (**it).client();
		if (c == NULL)
			continue;
		if ((**it).selected())
			from = c;
		else if ((**it).isTutor())
			to = c;
	}
	if (from == NULL)
		QMessageBox::critical(this,
			tr("Projection"),
			tr("No projection source selected.")
		);
	else if (to == NULL)
		QMessageBox::critical(this,
			tr("Projection"),
			tr("No tutor defined, or tutor is offline.")
		);
	else if (to == from)
		QMessageBox::critical(this,
			tr("Projection"),
			tr("Selected projection source is tutor.")
		);
	else
		prepareForProjection(from, to);
}

/**
 * Handle projection from tutor to all.
 * Get the client who is tutor and set the projectionSource of all
 * clients, except the tutor ones, to false.
 * Call prepareForProjection(from, to).
 */
void MainWindow::onButtonTutorToAll()
{
	//
	Client *from = NULL;
	for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
	{
		Client *c = (**it).client();
		if (c == NULL)
			continue;
		if ((**it).isTutor())
			from = c;
		else
			c->setProjectionSource(false);
	}
	if (from == NULL)
		QMessageBox::critical(this,
			tr("Projection"),
			tr("No tutor defined, or tutor is offline.")
		);
	else
		prepareForProjection(from, NULL);
}

/**
 * Handle the projection from Tutor to specific student.
 * Set the client who is tutor as from and the selected client as to.
 * Call prepareForProjection(from, to).
 */
void MainWindow::onButtonTutorToStudent()
{
	Client *from = NULL;
	Client *to = NULL;
	for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
	{
		Client *c = (**it).client();
		if (c == NULL)
			continue;
		if ((**it).selected())
			to = c;
		else if ((**it).isTutor())
			from = c;
	}
	if (to == NULL)
		QMessageBox::critical(this,
			tr("Projection"),
			tr("No projection source selected.")
		);
	else if (from == NULL)
		QMessageBox::critical(this,
			tr("Projection"),
			tr("No tutor defined, or tutor is offline.")
		);
	else if (to == from)
		QMessageBox::critical(this,
			tr("Projection"),
			tr("Selected projection target is tutor.")
		);
	else
		prepareForProjection(from, to);
}

/**
 * Handle Button StopProjection.
 * Set ProjectionSource of each client to false and create a NetworkMessage to
 * stop the active VNC Server and the active VNC Client(s).
 */
void MainWindow::onButtonStopProjection()
{
	for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
	{
		Client *c = (**it).client();
		if (c == NULL)
			continue;
		c->setDesiredProjectionSource(0);
		c->setProjectionSource(false);
	}
    NetworkMessage stopVncClientmsg;
    NetworkMessage stopVncServermsg;
    stopVncClientmsg.setField(_ID, _VNCCLIENT);
    stopVncServermsg.setField(_ID, _VNCSERVER);
	for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
	{
		Client *c = (**it).client();
		if (c == NULL)
			continue;
        c->sendMessage(stopVncClientmsg);
        c->sendMessage(stopVncServermsg);
	}
}

/**
 * Handle button to lock or unlock screens of client(s).
 * If already locked, do nothing, else create a NetworkMessage to lock (checked) or
 * unlock (!checked) the client(s), except the tutor.
 * @param checked
 */
void MainWindow::onButtonLock(bool checked)
{
	NetworkMessage msg;
	msg.setField(_ID, _LOCK);
	if (checked)
		msg.setField("ENABLE", QByteArray("1"));
	else
		msg.setField("ENABLE", QByteArray("0"));
	for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
	{
		Client *c = (**it).client();
		if (c == NULL || (**it).isTutor())
			continue; // Don't lock the tutor
		c->sendMessage(msg);
	}
}

/**
 * On button exit, close application.
 */
void MainWindow::onButtonExit()
{
	this->close();
}

/**
 * Handle button to set specific client as tutor.
 * Unset active tutor and set selected client, if not inactive, as new tutor.
 */
void MainWindow::onButtonSetAsTutor()
{
	bool selected = false;
	ConnectionFrame *oldTutor = NULL;
	bool changedTutor = false;
	for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
		{
		    selected = (*it)->selected();
		    if (!selected && (*it)->isTutor())
		    {
		    	oldTutor = (*it);
		    	(*it)->setTutor(false);
		    }
			if (selected && ((*it)->client() != NULL))
			{
				// This frame is marked to be Tutor.
				(*it)->setTutor(true);
				changedTutor = true;
			}
		}
	if (!changedTutor && oldTutor != NULL) {
		oldTutor->setTutor(true);
	}
}

/**
 * Handle from ListenServer signaled new client connection.
 * @param client
 */
void MainWindow::onClientConnected(Client* client)
{
	qDebug("ListenServer told MainWindow about new connection");
	connect(client, SIGNAL(authenticating(Client*, ClientLogin*)), this, SLOT(onClientAuthenticating(Client*, ClientLogin*)));
	connect(client, SIGNAL(authenticated(Client*)), this, SLOT(onClientAuthenticated(Client*)));
}

/**
 * Authenticate new Client client.
 * @param client
 * @param request
 */
void MainWindow::onClientAuthenticating(Client* client, ClientLogin* request)
{
	disconnect(client, SIGNAL(authenticating(Client*, ClientLogin*)), this, SLOT(onClientAuthenticating(Client*, ClientLogin*)));
	if (!request->accept) // Another receiver of that signal already rejected the client, so nothing to do
		return;
	bool inuse;
	QString check = request->name;
	int addnum = 1;
	do
	{
		inuse = false;
		for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
		{
			Client *c = (**it).client();
			if (c == NULL)
				continue;
			if (!c->isAuthed())
				continue;
			if (c->ip() == request->ip)
			{
				request->accept = false;
				return;
			}
			if (c->name() == check)
			{
				inuse = true;
				check = request->name + " (" + QString::number(++addnum) + ")";
				break;
			}
		}
	} while (inuse && addnum < 100);
	if (inuse)
		request->accept = false;
	else
		request->name = check;
}

/**
 * After authenticating new client, check if that's the first one and set tutor if necessary.
 * Also check the current VNC status and take these setting also for the new client.
 * @param client
 */
void MainWindow::onClientAuthenticated(Client* client)
{
	disconnect(client, SIGNAL(authenticated(Client*)), this, SLOT(onClientAuthenticated(Client*)));
	connect(client, SIGNAL(vncServerStateChange(Client*)), this, SLOT(onVncServerStateChange(Client*)), Qt::QueuedConnection);
	connect(client, SIGNAL(vncClientStateChange(Client*, int)), this, SLOT(onVncClientStateChange(Client*, int)), Qt::QueuedConnection);
	bool hasActiveTutor = false;
	ConnectionFrame *existing = NULL;
	for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
	{
		if ((*it)->computerId() == client->computerId())
			existing = *it;
		if ((*it)->isTutor())
		{
			if ((*it)->client() != NULL)
				hasActiveTutor = true;
		}
	}

	bool isTutor = false;
	if (!hasActiveTutor)
	{
		for (int i = 0; i < _tutorList.size(); i++)
		{
			// Check if client is possible tutor
			if (client->computerId() == _tutorList[i])
			{
				isTutor = true;
				break;
			}
		}
	}

	if (existing != NULL)
	{
		existing->setTutor(isTutor);
		existing->assignClient(client);
		return;
	}
	// New one, create
	ConnectionFrame *cf = createFrame();
	// Try to load last known position
	int x, y;
	bool ok;
	USER_SETTINGS(usr);
	ok = loadPosition(usr, client->computerId(), x, y);
	if (!ok)
	{
		SYSTEM_SETTINGS(sys);
		ok = loadPosition(sys, client->computerId(), x, y);
	}
	if (x >= _tilesX || y >= _tilesY)
		ok = false;
	if (ok)
	{
		if (x < 0)
			x = 0;
		if (y < 0)
			y = 0;
		qDebug("Move E");
		cf->move(x * _tileWidth, y * _tileHeight);
		onPlaceFrame(cf);
	}
	else
	{
		// Move to any free tile
		placeFrameInFreeSlot(cf);
	}
	// Set Tutor option
	cf->setTutor(isTutor);
	// Assign client instance
	cf->assignClient(client);
	// ################
	NetworkMessage msg;
	// If clients are currently locked, tell this new client
	if (ui->action_Lock->isChecked())
	{
		msg.reset();
		msg.setField(_ID, _LOCK);
		msg.setField("ENABLE", QByteArray("1"));
		client->sendMessage(msg);
	}
	// Same for VNC projections
	for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
	{
		Client *c = (**it).client();
		if (c != NULL && c != client && c->isActiveVncServer() && c->isProjectionSource())
		{
			msg.reset();
			msg.setField(_ID, _VNCCLIENT);
			msg.setField("HOST", c->ip());
			msg.setField("PORT", QString::number(c->vncPort()));
			msg.setField("ROPASS", c->vncRoPass());
			msg.setField("CLIENTID", QString::number(c->id()));
			msg.setField("CAPTION", c->name() + " @ " + c->host());
			client->sendMessage(msg);
			client->setDesiredProjectionSource(c->id());
			break;
		}
	}
}

/**
 * Handle if VNC Server State has changed.
 * Check if VNC server has been started/stopped on some client and start VNC server/reset pending
 * VNC projection information.
 * @param client
 */
void MainWindow::onVncServerStateChange(Client* client)
{
	if (!isValidClient(client)) // Check here because this slot is connected queued
		return;
	if (client->vncPort() > 0)
	{
		// VNC Server started on some client - start projection on all clients interested in that client's screen
		NetworkMessage msg;
		msg.setField(_ID, _VNCCLIENT);
		msg.setField("HOST", client->ip());
		msg.setField("PORT", QString::number(client->vncPort()));
		msg.setField("ROPASS", client->vncRoPass());
		msg.setField("CLIENTID", QString::number(client->id()));
		msg.setField("CAPTION", client->name() + " @ " + client->host());
		for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
		{
			Client *c = (**it).client();
			if (c == NULL || c->id() == client->id())
				continue; // Offline or self
			if (c->currentProjectionSource() == client->id())
				continue; // Already watching this client
			if (c->desiredProjectionSource() != client->id() && !client->isProjectionSource())
				continue; // Not interested
			c->sendMessage(msg);
		}
	}
	else
	{
		// VNC server stopped on some client or failed to start - reset local pending projection information
		// If at least one other client seemed to be waiting for this client's screen, pop up a message
		// on the console
		bool wasInterested = client->isProjectionSource();
		//qDebug() << "On VNC stop:" << client->ip() << "was projection source:" << wasInterested;
		client->setProjectionSource(false);
		for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
		{
			Client *c = (**it).client();
			if (c == NULL)
				continue;
			if (c->desiredProjectionSource() == client->id())
			{
				wasInterested = true;
				c->setDesiredProjectionSource(0);
			}
		}
		if (wasInterested && QDateTime::currentMSecsSinceEpoch() < _buttonBlockTime)
		{
			QMessageBox::information(this,
				tr("Projection Error"),
				tr("Could not send screen contents of %1 to other clients: VNC Startup failed.").arg(client->name())
			);
		}
	}
}

/**
 * Handle VNC client state change.
 * Check if any vnc client is in use, and if that is not the case, stop VNC Server.
 * @param client
 * @param lastProjectionSource
 */
void MainWindow::onVncClientStateChange(Client* client, int lastProjectionSource)
{
	if (!isValidClient(client)) // Check here because this slot is connected queued
		return;
	// If last source is not known or not existent, we cannot do anything meaningful here
	if (lastProjectionSource == 0)
		return;
	// Client is not a vnc client anymore. Check if the VNC server it was (supposedly) connected
	// to is still running, and kill it if there are no more clients connected to it.
	// (client->currentProjectionSource() will still contain the id of the server it was connected to during this event)
	// 1. check if vnc server is still running
	// 2. check if there are any other clients "using" that server
	bool inUse = false;
	Client *server = NULL;
	for (QList<ConnectionFrame*>::iterator it(_clientFrames.begin()); it != _clientFrames.end(); ++it)
	{
		Client *c = (**it).client();
		if (c == NULL)
			continue;
		if (c->id() == lastProjectionSource)
			server = c;
		if (c != client && c->currentProjectionSource() == lastProjectionSource)
		{
			inUse = true;
			break;
		}
	}
	// 3. kill server if applicable
	if (!inUse && server != NULL)
		server->stopVncServer();
}

void MainWindow::DisableButtons()
{
	ui->action_Lock->setDisabled(true);
	ui->action_BroadcastScreen->setDisabled(true);
	ui->action_TutorToAll->setDisabled(true);
	ui->action_StudentToTutor->setDisabled(true);
	ui->action_TutorToStudent->setDisabled(true);
	ui->action_StopProjection->setDisabled(true);
	ui->action_SetAsTutor->setEnabled(true);
}

void MainWindow::EnableButtons()
{
	ui->action_Lock->setEnabled(true);
	ui->action_BroadcastScreen->setEnabled(true);
	ui->action_TutorToAll->setEnabled(true);
	ui->action_StudentToTutor->setEnabled(true);
	ui->action_TutorToStudent->setEnabled(true);
	ui->action_StopProjection->setEnabled(true);
	ui->action_SetAsTutor->setEnabled(true);
}