Zoom/center the page map so that all locations are in view

src/locationhelper.h

@@ -0,0 +1,22 @@
+// SPDX-FileCopyrightText: 2023 Volker Krause <vkrause@kde.org>
+// SPDX-License-Identifier: LGPL-2.0-or-later
+
+#include "linkpreviewer.h"
+#include <QMetaType>
+#include <QRectF>
+
+/** Location related helper functions for QML. */
+class LocationHelper
+{
+    Q_GADGET
+public:
+    /** Unite two rectanlges. */
+    Q_INVOKABLE static QRectF unite(const QRectF &r1, const QRectF &r2);
+    /** Returns the center of @p r. */
+    Q_INVOKABLE static QPointF center(const QRectF &r);
+
+    /** Returns the highest zoom level to fit @r into a map of size @p mapWidth x @p mapHeight. */
+    Q_INVOKABLE static float zoomToFit(const QRectF &r, float mapWidth, float mapHeight);
+};
+
+Q_DECLARE_METATYPE(LocationHelper)