cleanup: move timestampToDateTime() to qthelper.cpp

Move this function from maintab.cpp to qthelper.cpp. Since the
functionality was used in numerous places, use the helper function
there as well. This removes a number of inconsistencies. For example,
sometime setTimeSpec(Qt::UTC) was called, even though the
QDateTime object was already created with that time spec.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

7 files changed, 22 insertions, 28 deletions

diff --git a/core/gpslocation.cpp b/core/gpslocation.cpp
index feea645e1..ebd5b1950 100644
--- a/core/gpslocation.cpp
+++ b/core/gpslocation.cpp
@@ -133,7 +133,7 @@ QString GpsLocation::currentPosition()
 	if (!hasLocationsSource())
 		return tr("Unknown GPS location (no GPS source)");
 	if (m_trackers.count()) {
-		QDateTime lastFixTime =	QDateTime().fromMSecsSinceEpoch((m_trackers.lastKey() - gettimezoneoffset(m_trackers.lastKey())) * 1000);
+		QDateTime lastFixTime =	timestampToDateTime(m_trackers.lastKey() - gettimezoneoffset(m_trackers.lastKey()));
 		QDateTime now = QDateTime::currentDateTime();
 		int delta = lastFixTime.secsTo(now);
 		qDebug() << "lastFixTime" << lastFixTime.toString() << "now" << now.toString() << "delta" << delta;
@@ -173,7 +173,7 @@ void GpsLocation::newPosition(QGeoPositionInfo pos)
 	if (!nr || waitingForPosition || delta > prefs.time_threshold ||
 	    lastCoord.distanceTo(pos.coordinate()) > prefs.distance_threshold) {
 		QString msg = QStringLiteral("received new position %1 after delta %2 threshold %3 (now %4 last %5)");
-		status(qPrintable(msg.arg(pos.coordinate().toString()).arg(delta).arg(prefs.time_threshold).arg(pos.timestamp().toString()).arg(QDateTime().fromMSecsSinceEpoch(lastTime * 1000).toString())));
+		status(qPrintable(msg.arg(pos.coordinate().toString()).arg(delta).arg(prefs.time_threshold).arg(pos.timestamp().toString()).arg(timestampToDateTime(lastTime).toString())));
 		waitingForPosition = false;
 		acquiredPosition();
 		gpsTracker gt;
@@ -182,7 +182,7 @@ void GpsLocation::newPosition(QGeoPositionInfo pos)
 		gt.location = create_location(pos.coordinate().latitude(), pos.coordinate().longitude());
 		addFixToStorage(gt);
 		gpsTracker gtNew = m_trackers.last();
-		qDebug() << "newest fix is now at" << QDateTime().fromMSecsSinceEpoch(gtNew.when - gettimezoneoffset(gtNew.when) * 1000).toString();
+		qDebug() << "newest fix is now at" << timestampToDateTime(gtNew.when - gettimezoneoffset(gtNew.when)).toString();
 	}
 }
 
diff --git a/core/qthelper.cpp b/core/qthelper.cpp
index e1329ca26..561dd9213 100644
--- a/core/qthelper.cpp
+++ b/core/qthelper.cpp
@@ -696,12 +696,19 @@ int gettimezoneoffset(timestamp_t when)
 	if (when == 0)
 		dt1 = QDateTime::currentDateTime();
 	else
-		dt1 = QDateTime::fromMSecsSinceEpoch(when * 1000);
+		dt1 = timestampToDateTime(when);
 	dt2 = dt1.toUTC();
 	dt1.setTimeSpec(Qt::UTC);
 	return dt2.secsTo(dt1);
 }
 
+QDateTime timestampToDateTime(timestamp_t when)
+{
+	// Subsurface always uses "local time" as in "whatever was the local time at the location"
+	// so all time stamps have no time zone information and are in UTC
+	return QDateTime::fromMSecsSinceEpoch(1000 * when, Qt::UTC);
+}
+
 QString render_seconds_to_string(int seconds)
 {
 	if (seconds % 60 == 0)
@@ -984,8 +991,7 @@ QString get_trip_date_string(timestamp_t when, int nr, bool getday)
 {
 	struct tm tm;
 	utc_mkdate(when, &tm);
-	QDateTime localTime = QDateTime::fromMSecsSinceEpoch(1000*when,Qt::UTC);
-	localTime.setTimeSpec(Qt::UTC);
+	QDateTime localTime = timestampToDateTime(when);
 
 	QString suffix = " " + gettextFromC::tr("(%n dive(s))", "", nr);
 	if (getday)
diff --git a/core/qthelper.h b/core/qthelper.h
index 8cd31b29c..b0cab8b15 100644
--- a/core/qthelper.h
+++ b/core/qthelper.h
@@ -62,6 +62,7 @@ QString getSubsurfaceDataPath(QString folderToFind);
 QString getPrintingTemplatePathUser();
 QString getPrintingTemplatePathBundle();
 int gettimezoneoffset(timestamp_t when = 0);
+QDateTime timestampToDateTime(timestamp_t when);
 int parseDurationToSeconds(const QString &text);
 int parseLengthToMm(const QString &text);
 int parseTemperatureToMkelvin(const QString &text);
diff --git a/core/subsurface-qt/diveobjecthelper.cpp b/core/subsurface-qt/diveobjecthelper.cpp
index 7c8651507..45cb73868 100644
--- a/core/subsurface-qt/diveobjecthelper.cpp
+++ b/core/subsurface-qt/diveobjecthelper.cpp
@@ -328,15 +328,13 @@ DiveObjectHelperGrantlee::DiveObjectHelperGrantlee(const struct dive *d) :
 
 QString DiveObjectHelper::date() const
 {
-	QDateTime localTime = QDateTime::fromMSecsSinceEpoch(1000 * timestamp, Qt::UTC);
-	localTime.setTimeSpec(Qt::UTC);
+	QDateTime localTime = timestampToDateTime(timestamp);
 	return localTime.date().toString(prefs.date_format_short);
 }
 
 QString DiveObjectHelper::time() const
 {
-	QDateTime localTime = QDateTime::fromMSecsSinceEpoch(1000 * timestamp, Qt::UTC);
-	localTime.setTimeSpec(Qt::UTC);
+	QDateTime localTime = timestampToDateTime(timestamp);
 	return localTime.time().toString(prefs.time_format);
 }
 
diff --git a/desktop-widgets/mainwindow.cpp b/desktop-widgets/mainwindow.cpp
index b3f474de8..94c51279f 100644
--- a/desktop-widgets/mainwindow.cpp
+++ b/desktop-widgets/mainwindow.cpp
@@ -865,7 +865,7 @@ void MainWindow::on_actionReplanDive_triggered()
 	graphics->clearHandlers();
 	setApplicationState(ApplicationState::PlanDive);
 	divePlannerWidget->setReplanButton(true);
-	divePlannerWidget->setupStartTime(QDateTime::fromMSecsSinceEpoch(1000 * current_dive->when, Qt::UTC));
+	divePlannerWidget->setupStartTime(timestampToDateTime(current_dive->when));
 	if (current_dive->surface_pressure.mbar)
 		divePlannerWidget->setSurfacePressure(current_dive->surface_pressure.mbar);
 	if (current_dive->salinity)
diff --git a/desktop-widgets/tab-widgets/maintab.cpp b/desktop-widgets/tab-widgets/maintab.cpp
index d11581516..81c56a486 100644
--- a/desktop-widgets/tab-widgets/maintab.cpp
+++ b/desktop-widgets/tab-widgets/maintab.cpp
@@ -307,14 +307,6 @@ void MainTab::updateNotes(const struct dive *d)
 	}
 }
 
-static QDateTime timestampToDateTime(timestamp_t when)
-{
-	// Subsurface always uses "local time" as in "whatever was the local time at the location"
-	// so all time stamps have no time zone information and are in UTC
-	QDateTime localTime = QDateTime::fromMSecsSinceEpoch(1000 * when, Qt::UTC);
-	localTime.setTimeSpec(Qt::UTC);
-	return localTime;
-}
 void MainTab::updateDateTime(const struct dive *d)
 {
 	QDateTime localTime = timestampToDateTime(d->when);
@@ -617,8 +609,7 @@ void MainTab::on_dateEdit_editingFinished()
 {
 	if (ignoreInput || !current_dive)
 		return;
-	QDateTime dateTime = QDateTime::fromMSecsSinceEpoch(1000*current_dive->when, Qt::UTC);
-	dateTime.setTimeSpec(Qt::UTC);
+	QDateTime dateTime = timestampToDateTime(current_dive->when);
 	dateTime.setDate(ui.dateEdit->date());
 	shiftTime(dateTime);
 }
@@ -627,8 +618,7 @@ void MainTab::on_timeEdit_editingFinished()
 {
 	if (ignoreInput || !current_dive)
 		return;
-	QDateTime dateTime = QDateTime::fromMSecsSinceEpoch(1000*current_dive->when, Qt::UTC);
-	dateTime.setTimeSpec(Qt::UTC);
+	QDateTime dateTime = timestampToDateTime(current_dive->when);
 	dateTime.setTime(ui.timeEdit->time());
 	shiftTime(dateTime);
 }
diff --git a/qt-models/divetripmodel.cpp b/qt-models/divetripmodel.cpp
index a153b31c7..a48c827dd 100644
--- a/qt-models/divetripmodel.cpp
+++ b/qt-models/divetripmodel.cpp
@@ -63,7 +63,7 @@ QString DiveTripModelBase::tripShortDate(const dive_trip *trip)
 {
 	if (!trip)
 		return QString();
-	QDateTime firstTime = QDateTime::fromMSecsSinceEpoch(1000*trip_date(trip), Qt::UTC);
+	QDateTime firstTime = timestampToDateTime(trip_date(trip));
 	QString firstMonth = firstTime.toString("MMM");
 	return QStringLiteral("%1\n'%2").arg(firstMonth,firstTime.toString("yy"));
 }
@@ -79,10 +79,10 @@ QString DiveTripModelBase::tripTitle(const dive_trip *trip)
 
 	if (title.isEmpty()) {
 		// so use the date range
-		QDateTime firstTime = QDateTime::fromMSecsSinceEpoch(1000*trip_date(trip), Qt::UTC);
+		QDateTime firstTime = timestampToDateTime(trip_date(trip));
 		QString firstMonth = firstTime.toString("MMM");
 		QString firstYear = firstTime.toString("yyyy");
-		QDateTime lastTime = QDateTime::fromMSecsSinceEpoch(1000*trip->dives.dives[0]->when, Qt::UTC);
+		QDateTime lastTime = timestampToDateTime(trip->dives.dives[0]->when);
 		QString lastMonth = lastTime.toString("MMM");
 		QString lastYear = lastTime.toString("yyyy");
 		if (lastMonth == firstMonth && lastYear == firstYear)
@@ -201,8 +201,7 @@ QVariant DiveTripModelBase::diveData(const struct dive *d, int column, int role)
 	// variable in the QtQuick list view. That has to be a string because it will try
 	// to do locale-aware sorting. And amazingly this can't be changed.
 	case MobileListModel::DateTimeRole: {
-		QDateTime localTime = QDateTime::fromMSecsSinceEpoch(1000 * d->when, Qt::UTC);
-		localTime.setTimeSpec(Qt::UTC);
+		QDateTime localTime = timestampToDateTime(d->when);
 		return QStringLiteral("%1 %2").arg(localTime.date().toString(prefs.date_format_short),
 						   localTime.time().toString(prefs.time_format));
 		}