Planner: wild guess attempt to fix a crash on Mac

Staring at the stack trace it seems that it gets into an infinite
recursion when trying to recalculate after being alerted to a change on
the ruler. I cannot recreate this here (not on Linux, not on Mac), but
here's a random attempt to prevent the issue: simply refuse to recalculate
the ruler while in Add or Plan mode.

Crude, but might show us if this really is the issue. Otherwise it's easy
enough to revert this change. The qDebug() in there should tell us if
people on a Mac do indeed see this even without moving the ruler around in
Add or Plan mode.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

qt-ui/profile/profilewidget2.cpp

@@ -830,6 +830,11 @@ bool ProfileWidget2::isPlanner()
 	return currentState == PLAN;
 }
 
+bool ProfileWidget2::isAddOrPlanner()
+{
+	return currentState == PLAN || currentState == ADD;
+}
+
 void ProfileWidget2::contextMenuEvent(QContextMenuEvent *event)
 {
 	if (currentState == ADD || currentState == PLAN) {

qt-ui/profile/profilewidget2.h

@@ -72,6 +72,7 @@ public:
 	void setPrintMode(bool mode, bool grayscale = false);
 	bool isPointOutOfBoundaries(const QPointF &point) const;
 	bool isPlanner();
+	bool isAddOrPlanner();
 	State currentState;
 
 public

qt-ui/profile/ruleritem.cpp

@@ -1,7 +1,8 @@
 #include "ruleritem.h"
 #include "divetextitem.h"
 #include "profilewidget2.h"
-#include "../preferences.h"
+#include "preferences.h"
+#include "mainwindow.h"
 
 #include <QFont>
 #include <QFontMetrics>
@@ -59,9 +60,19 @@ void RulerNodeItem2::recalculate()
 
 QVariant RulerNodeItem2::itemChange(GraphicsItemChange change, const QVariant &value)
 {
-	if (change == ItemPositionHasChanged) {
+	// only run this if we actually have a ruler and are not adding or planning a dive
+	ProfileWidget2 *profWidget = NULL;
+	if (scene() && scene()->views().count())
+		profWidget = qobject_cast<ProfileWidget2 *>(scene()->views().first());
+	if (ruler &&
+	    profWidget &&
+	    !profWidget->isAddOrPlanner() &&
+	    change == ItemPositionHasChanged) {
 		recalculate();
 		ruler->recalculate();
+	} else {
+		if (profWidget && profWidget->isAddOrPlanner())
+			qDebug() << "don't recalc ruler on Add/Plan";
 	}
 	return QGraphicsEllipseItem::itemChange(change, value);
 }