[server] Improved disabling of toolbar buttons depending on context

 * Disable tutor to student / student to tutor if no tutor online
 * Disable above buttons if selected frame is tutor
 * Disable lock single client button if selected client is tutor
... And many more

 Closes #3399

2 files changed, 56 insertions, 77 deletions

diff --git a/src/server/mainwindow/mainwindow.cpp b/src/server/mainwindow/mainwindow.cpp
index e23e755..a7648b9 100644
--- a/src/server/mainwindow/mainwindow.cpp
+++ b/src/server/mainwindow/mainwindow.cpp
@@ -110,7 +110,6 @@ MainWindow::MainWindow(QWidget* parent) :
 	ui->toolBar->insertWidget(ui->action_TutorToStudent, _examModeLabel);
 
 	serverApp->setExam(false);
-	clientCountChanged();
 
 	// Close button in tool bar
 	connect(ui->action_Exit, SIGNAL(triggered()), this, SLOT(onButtonExit()));
@@ -127,37 +126,23 @@ MainWindow::MainWindow(QWidget* parent) :
 	connect(ui->actionReload_Room_Configuration, SIGNAL(triggered()), this, SLOT(onButtonReloadRoomConfig()));
 	connect(ui->action_DeleteClient, SIGNAL(triggered()), this, SLOT(onDeleteClient()));
 
-	// /* In exam-mode: disable most features */
-	// QSharedPointer<QSettings> conf = Global::getSettings();
-	// if (conf->contains("examMode")) {
-	//     Global::setExam(conf->value("examMode").toBool());
-	// }
-
-	/* disable context-sensitive buttons by default */
-	_contextButtons
-	        << ui->action_DeleteClient
-	        << ui->action_StudentToTutor
-	        << ui->action_StudentToTutorExclusive
-	        << ui->action_SetAsTutor
-			<< ui->action_TutorToStudent
-			<< ui->action_LockSingle;
-
-	lockContextButtons();
-
 	/* Stuff for the button lock */
 	//Setup a timeout
 	_buttonLockTimer = new QTimer(this);
 	_buttonLockTimer->setSingleShot(true);
-	_buttonLockTimer->setInterval(_buttonBlockTime);
+	_buttonLockTimer->setInterval(BUTTON_BLOCK_TIME);
 	connect(_buttonLockTimer, SIGNAL(timeout()), this, SLOT(enableButtons()));
 	// Define the locking buttons
 	_lockingButtons
+			<< ui->action_DeleteClient
+			<< ui->action_StudentToTutor
+			<< ui->action_StudentToTutorExclusive
+			<< ui->action_SetAsTutor
+			<< ui->action_TutorToStudent
+			<< ui->action_LockSingle
 	        << ui->action_Lock
-	        << ui->action_TutorToAll
-	        << ui->action_StudentToTutor
-	        << ui->action_TutorToStudent
-	        << ui->action_StopProjection
-	        << ui->action_SetAsTutor;
+			<< ui->action_TutorToAll
+			<< ui->action_StopProjection;
 
 	// Clicking the session name label shows the edit field for it
 	connect(_sessionNameLabel, SIGNAL(clicked()), this, SLOT(onSessionNameClick()));
@@ -221,6 +206,9 @@ void MainWindow::clientCountChanged()
 		// Remember client count
 		_lastClientCount = clientCount;
 	}
+	// Also we might have to enable/disable buttons in the toolbar if the
+	// client frame is currently selected
+	updateContextButtonStates();
 }
 
 MainWindow::~MainWindow()
@@ -544,33 +532,27 @@ void MainWindow::resizeEvent(QResizeEvent* /* e */ )
 	}
 }
 
-
-void MainWindow::lockContextButtons()
+void MainWindow::updateContextButtonStates()
 {
-	for (auto it = _contextButtons.begin(); it != _contextButtons.end(); ++it) {
-		(*it)->setEnabled(false);
-	}
+	if (_buttonLockTimer->isActive()) // If buttons are disabled for cooldown, don't do anything
+		return;
+	const ConnectionFrame *selected = getSelectedFrame();
+	const ConnectionFrame *tutor = getTutorFrame();
+	const bool somethingSelected = (selected != nullptr);
+	const bool selectedOnline = (selected != nullptr && selected->client() != nullptr);
+	const bool tutorOnline = (tutor != nullptr && tutor->client() != nullptr);
+	// Deletion only for offline clients, tutor if anything is selected, locking only for online clients
+	ui->action_DeleteClient->setEnabled(somethingSelected && !selectedOnline);
+	ui->action_SetAsTutor->setEnabled(somethingSelected);
+	ui->action_LockSingle->setEnabled(selectedOnline && selected != tutor);
+	// Don't allow projection to self
+	ui->action_StudentToTutorExclusive->setEnabled(somethingSelected && selected != tutor && tutorOnline);
+	ui->action_StudentToTutor->setEnabled(somethingSelected && selected != tutor && tutorOnline);
+	ui->action_TutorToStudent->setEnabled(somethingSelected && selected != tutor && tutorOnline);
+	// Only allow tutor broadcast if they're online
+	ui->action_TutorToAll->setEnabled(tutorOnline);
 }
 
-void MainWindow::unlockContextButtons()
-{
-	for (auto it = _contextButtons.begin(); it != _contextButtons.end(); ++it) {
-		(*it)->setEnabled(true);
-	}
-	/* and disable some again based on special rules */
-	if (getSelectedFrame()->client() != nullptr) {
-		ui->action_DeleteClient->setEnabled(false);
-	}
-	if (getSelectedFrame()->client() == nullptr) {
-		ui->action_SetAsTutor->setEnabled(false);
-		ui->action_StudentToTutorExclusive->setEnabled(false);
-		ui->action_StudentToTutor->setEnabled(false);
-		ui->action_TutorToStudent->setEnabled(false);
-		ui->action_LockSingle->setEnabled(false);
-	}
-
-
-}
 /***************************************************************************//**
  * Handle Mouse Release Event.
  * Check if click was inside the frame and if that is the case, set the selection of each connected
@@ -587,9 +569,9 @@ void MainWindow::mouseReleaseEvent(QMouseEvent* e)
 		return;
 	const QSize frame(ui->frmRoom->size());
 	if (frame.width() > pos.x() && frame.height() > pos.y()) {
-		lockContextButtons();
 		if (getSelectedFrame() != nullptr) {
 			getSelectedFrame()->setSelection(false);
+			updateContextButtonStates();
 		}
 	}
 }
@@ -640,18 +622,18 @@ void MainWindow::onPlaceFrame(ConnectionFrame* connectionFrame)
  */
 void MainWindow::onFrameClicked(ConnectionFrame* frame)
 {
+	ConnectionFrame *current = getSelectedFrame();
 	// If same frame is clicked again,, do nothing
-	if (getSelectedFrame() == frame)
+	if (current == frame)
 		return;
 
 	// If another frame has been selected, unselect it
 	// Set the ui selected and set a new reference
-	if (getSelectedFrame() != nullptr) {
-		getSelectedFrame()->setSelection(false);
+	if (current != nullptr) {
+		current->setSelection(false);
 	}
 	frame->setSelection(true);
-
-	unlockContextButtons();
+	updateContextButtonStates();
 }
 
 /***************************************************************************//**
@@ -794,6 +776,7 @@ void MainWindow::reloadCurrentRoom()
 
 	/* and force a resize event (this scales the image)  */
 	resizeEvent(nullptr);
+	clientCountChanged();
 }
 
 void MainWindow::onReloadRoomOk()
@@ -1057,26 +1040,27 @@ void MainWindow::onButtonExit()
  */
 void MainWindow::onButtonSetAsTutor()
 {
-	// If no frame is selected, warning.
-	if (getSelectedFrame() == nullptr) {
+	ConnectionFrame *selected = getSelectedFrame();
+	ConnectionFrame *tutor = getTutorFrame();
+
+	if (selected == nullptr) {
 		QMessageBox::critical(this, tr("Selection"), tr("No client is selected."));
 		return;
 	}
 
-	// If frame of inactive client has been selected unselect it
-	if (getSelectedFrame()->client() != nullptr) {
-		getSelectedFrame()->client()->lockScreen(false);
+	// Unlock client about to become a tutor, just in case
+	if (selected->client() != nullptr) {
+		selected->client()->lockScreen(false);
 	}
-
 	// If same frame is already tutor, do nothing
-	if (getSelectedFrame() == getTutorFrame())
+	if (selected == tutor)
 		return;
-
 	// Else unset the old and set the new tutor
-	if (getTutorFrame() != nullptr) {
-		getTutorFrame()->setTutor(false);
+	if (tutor != nullptr) {
+		tutor->setTutor(false);
 	}
-	getSelectedFrame()->setTutor(true);
+	selected->setTutor(true);
+	updateContextButtonStates();
 }
 
 /***************************************************************************//**
@@ -1179,8 +1163,9 @@ void MainWindow::onClientAuthenticated(Client* client)
  */
 void MainWindow::onVncServerStateChange(Client* client)
 {
-	if (client == getClientFromId(_streamingSource))
+	if (client == getClientFromId(_streamingSource)) {
 		enableButtons();
+	}
 
 	if (client->isActiveVncServer()) {
 		// apply the desired projection sources
@@ -1265,9 +1250,8 @@ void MainWindow::onVncClientStateChange(Client* client)
  */
 void MainWindow::disableButtons()
 {
-	qDebug() << "DisableButtons()";
 	_buttonLockTimer->start();
-	foreach (QAction * a, _lockingButtons) {
+	for (QAction *a : _lockingButtons) {
 		a->setDisabled(true);
 	}
 }
@@ -1277,11 +1261,11 @@ void MainWindow::disableButtons()
  */
 void MainWindow::enableButtons()
 {
-	qDebug() << "EnableButtons()";
 	_buttonLockTimer->stop();
-	foreach (QAction * a, _lockingButtons) {
+	for (QAction *a : _lockingButtons) {
 		a->setEnabled(true);
 	}
+	updateContextButtonStates(); // In case user changed selection while buttons were disabled
 }
 
 
@@ -1303,7 +1287,6 @@ void MainWindow::onDeleteClient()
 		frame->hide();
 		frame->deleteLater();
 		_clientFrames.removeAll(frame);
-		lockContextButtons();
 		clientCountChanged();
 		return;
 	}
diff --git a/src/server/mainwindow/mainwindow.h b/src/server/mainwindow/mainwindow.h
index 59d50fc..f42fc73 100644
--- a/src/server/mainwindow/mainwindow.h
+++ b/src/server/mainwindow/mainwindow.h
@@ -55,10 +55,7 @@ private:
 	// Button block stuff
 	QTimer              *_buttonLockTimer;
 	QList<QAction*>     _lockingButtons;
-	static const qint64 _buttonBlockTime = 2000;
-
-	/* Context-sensitive Buttons */
-	QList<QAction*> _contextButtons;
+        static const qint64 BUTTON_BLOCK_TIME = 2000;
 
 	// Management stuff
 	enum class Mode
@@ -96,8 +93,7 @@ private:
 	int getTileWidthPx() const;
 	int getTileHeightPx() const;
 
-	void lockContextButtons();
-	void unlockContextButtons();
+        void updateContextButtonStates();
 
 	void reloadCurrentRoom();