From 787a23f017f2904a54282b0789478745c7f934e0 Mon Sep 17 00:00:00 2001
From: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>
Date: Wed, 30 Jun 2021 07:17:40 +0200
Subject: [PATCH] profile: implement "empty state" in desktop's ProfileWidget

The profile has an "empty state" showing the subsurface logo,
which is active when no dive is selected.

Switching to/from this mode is quite complex, because all the
chart features have to be hidden/shown, etc. Moreover, this mode
is not needed on mobile, where multiple ProfileWidgets can
be active at the same time and every dive has at least a
"faked" profile.

Therefore, implement this mode directly in the desktop
version of the widget. This makes the rescaling distinctly
less cumbersome. It is implemented using a QStackedWidget,
which switches between the profile and the logo.

This commit does not remove the empty state from the profile.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>
---
 desktop-widgets/profilewidget.cpp | 78 +++++++++++++++++++++++++++++--
 desktop-widgets/profilewidget.h   |  4 ++
 2 files changed, 78 insertions(+), 4 deletions(-)

diff --git a/desktop-widgets/profilewidget.cpp b/desktop-widgets/profilewidget.cpp
index 2b1b28c83..fa264cd70 100644
--- a/desktop-widgets/profilewidget.cpp
+++ b/desktop-widgets/profilewidget.cpp
@@ -8,6 +8,45 @@
 
 #include <QToolBar>
 #include <QHBoxLayout>
+#include <QStackedWidget>
+#include <QLabel>
+
+// A resizing display of the Subsurface logo when no dive is shown
+class EmptyView : public QLabel {
+public:
+	EmptyView(QWidget *parent = nullptr);
+	~EmptyView();
+private:
+	QPixmap logo;
+	void update();
+	void resizeEvent(QResizeEvent *) override;
+};
+
+EmptyView::EmptyView(QWidget *parent) : QLabel(parent),
+	logo(":poster-icon")
+{
+	QPalette pal;
+	pal.setColor(QPalette::Window, getColor(::BACKGROUND));
+	setAutoFillBackground(true);
+	setPalette(pal);
+	setMinimumSize(1,1);
+	setAlignment(Qt::AlignHCenter);
+	update();
+}
+
+EmptyView::~EmptyView()
+{
+}
+
+void EmptyView::update()
+{
+	setPixmap(logo.scaled(size(), Qt::KeepAspectRatio, Qt::SmoothTransformation));
+}
+
+void EmptyView::resizeEvent(QResizeEvent *)
+{
+	update();
+}
 
 ProfileWidget::ProfileWidget()
 {
@@ -26,18 +65,25 @@ ProfileWidget::ProfileWidget()
 			   ui.profHR, // very few dive computers support this
 			   ui.profTissues }; // maybe less frequently used
 
+	emptyView.reset(new EmptyView);
+
 	view.reset(new ProfileWidget2(DivePlannerPointsModel::instance(), 1.0, this));
 	QToolBar *toolBar = new QToolBar(this);
 	for (QAction *a: toolbarActions)
 		toolBar->addAction(a);
 	toolBar->setOrientation(Qt::Vertical);
 	toolBar->setIconSize(QSize(24, 24));
+
+	stack = new QStackedWidget(this);
+	stack->addWidget(emptyView.get());
+	stack->addWidget(view.get());
+
 	QHBoxLayout *layout = new QHBoxLayout(this);
 	layout->setSpacing(0);
 	layout->setMargin(0);
 	layout->setContentsMargins(0, 0, 0, 0);
 	layout->addWidget(toolBar);
-	layout->addWidget(view.get());
+	layout->addWidget(stack);
 	setLayout(layout);
 
 	// Toolbar Connections related to the Profile Update
@@ -128,9 +174,33 @@ void ProfileWidget::setDive(const struct dive *d)
 void ProfileWidget::plotCurrentDive()
 {
 	setEnabledToolbar(current_dive != nullptr);
-	if (current_dive)
-		setDive(current_dive);
-	view->plotDive(current_dive, dc_number);
+	if (current_dive) {
+		stack->setCurrentIndex(1);
+		bool freeDiveMode = current_dive->dc.divemode == FREEDIVE;
+		ui.profCalcCeiling->setDisabled(freeDiveMode);
+		ui.profCalcCeiling->setDisabled(freeDiveMode);
+		ui.profCalcAllTissues ->setDisabled(freeDiveMode);
+		ui.profIncrement3m->setDisabled(freeDiveMode);
+		ui.profDcCeiling->setDisabled(freeDiveMode);
+		ui.profPhe->setDisabled(freeDiveMode);
+		ui.profPn2->setDisabled(freeDiveMode); //TODO is the same as scuba?
+		ui.profPO2->setDisabled(freeDiveMode); //TODO is the same as scuba?
+		ui.profTankbar->setDisabled(freeDiveMode);
+		ui.profMod->setDisabled(freeDiveMode);
+		ui.profNdl_tts->setDisabled(freeDiveMode);
+		ui.profDeco->setDisabled(freeDiveMode);
+		ui.profEad->setDisabled(freeDiveMode);
+		ui.profSAC->setDisabled(freeDiveMode);
+		ui.profTissues->setDisabled(freeDiveMode);
+
+		ui.profRuler->setDisabled(false);
+		ui.profScaled->setDisabled(false); // measuring and scaling
+		ui.profTogglePicture->setDisabled(false);
+		ui.profHR->setDisabled(false);
+		view->plotDive(current_dive, dc_number);
+	} else {
+		stack->setCurrentIndex(0);
+	}
 }
 
 void ProfileWidget::setPlanState(const struct dive *d, int dc)
diff --git a/desktop-widgets/profilewidget.h b/desktop-widgets/profilewidget.h
index 8d19aaa32..467ade1a9 100644
--- a/desktop-widgets/profilewidget.h
+++ b/desktop-widgets/profilewidget.h
@@ -10,6 +10,8 @@
 #include <memory>
 
 class ProfileWidget2;
+class EmptyView;
+class QStackedWidget;
 
 class ProfileWidget : public QWidget {
 	Q_OBJECT
@@ -26,8 +28,10 @@ slots:
 	void unsetProfHR();
 	void unsetProfTissues();
 private:
+	std::unique_ptr<EmptyView> emptyView;
 	std::vector<QAction *> toolbarActions;
 	Ui::ProfileWidget ui;
+	QStackedWidget *stack;
 	void setDive(const struct dive *d);
 };