Allow to export favorite locations to a GPX file

This is compatible with Nextcloud Maps and can be imported there.

src/app/FavoriteLocationPage.qml

@@ -7,6 +7,7 @@
 import QtQuick 2.5
 import QtQuick.Layouts 1.1
 import QtQuick.Controls 2.1 as QQC2
+import Qt.labs.platform 1.1 as Platform
 import QtLocation 5.11 as QtLocation
 import QtPositioning 5.11
 import org.kde.kirigami 2.12 as Kirigami
@@ -34,6 +35,15 @@ Kirigami.Page {
 
     }
 
+    Platform.FileDialog {
+        id: favoriteGpxExportDialog
+        fileMode: Platform.FileDialog.SaveFile
+        title: i18n("Export Favorite Locations")
+        folder: Platform.StandardPaths.writableLocation(StandardPaths.DocumentsLocation)
+        nameFilters: [i18n("GPX Files (*.gpx)")]
+        onAccepted: FavoriteLocationModel.exportToGpx(file)
+    }
+
    actions.main: Kirigami.Action {
         icon.name: "crosshairs"
         text: i18n("Pick Location")
@@ -66,6 +76,11 @@ Kirigami.Page {
                 FavoriteLocationModel.removeLocation(combo.currentIndex);
                 combo.currentIndex = Math.min(prevIndex, combo.count - 1);
             }
+        },
+        Kirigami.Action {
+            text: i18n("Export to GPX")
+            icon.name: "export-symbolic"
+            onTriggered: favoriteGpxExportDialog.open()
         }
     ]
 

src/app/favoritelocationmodel.cpp

@@ -5,7 +5,9 @@
 */
 
 #include "favoritelocationmodel.h"
+#include "gpxexport.h"
 #include "json.h"
+#include "logging.h"
 
 #include <KLocalizedString>
 
@@ -253,3 +255,20 @@ void FavoriteLocationModel::saveLocations() const
 
     f.write(QJsonDocument(FavoriteLocation::toJson(m_locations)).toJson());
 }
+
+void FavoriteLocationModel::exportToGpx(const QString &filePath) const
+{
+    if (filePath.isEmpty()) {
+        return;
+    }
+
+    QFile f(QUrl(filePath).isLocalFile() ? QUrl(filePath).toLocalFile() : filePath);
+    if (!f.open(QFile::WriteOnly)) {
+        qCWarning(Log) << f.errorString() << f.fileName();
+        return;
+    }
+    GpxExport exporter(&f);
+    for (const auto &fav : m_locations) {
+        exporter.writeFavoriteLocation(fav);
+    }
+}

src/app/favoritelocationmodel.h

@@ -77,6 +77,9 @@ public:
      */
     void setFavoriteLocations(std::vector<FavoriteLocation> &&locs);
 
+    /** Export to GPX. */
+    Q_INVOKABLE void exportToGpx(const QString &filePath) const;
+
     int rowCount(const QModelIndex &parent = {}) const override;
     QVariant data(const QModelIndex &index, int role) const override;
     bool setData(const QModelIndex & index, const QVariant & value, int role) override;

src/app/gpxexport.cpp

@@ -5,6 +5,7 @@
 */
 
 #include "gpxexport.h"
+#include "favoritelocationmodel.h"
 #include "transfer.h"
 
 #include <KItinerary/Event>
@@ -106,3 +107,10 @@ void GpxExport::writeJourneySection(const KPublicTransport::JourneySection &sect
         }
     }
 }
+
+void GpxExport::writeFavoriteLocation(const FavoriteLocation &fav)
+{
+    m_writer.writeStartWaypoint(fav.latitude(), fav.longitude());
+    m_writer.writeName(fav.name());
+    m_writer.writeEndWaypoint();
+}

src/app/gpxexport.h

@@ -11,6 +11,7 @@
 
 #include <gpx/gpxwriter.h>
 
+class FavoriteLocation;
 class Transfer;
 
 /** Trip group to GPX export. */
@@ -22,6 +23,7 @@ public:
 
     void writeReservation(const QVariant &res, const KPublicTransport::JourneySection &journey = {});
     void writeTransfer(const Transfer &transfer);
+    void writeFavoriteLocation(const FavoriteLocation &fav);
 
     inline void writeStartRoute() { m_writer.writeStartRoute(); }
     inline void writeEndRoute() { m_writer.writeEndRoute(); }

src/gpx/gpxwriter.cpp

@@ -45,6 +45,18 @@ void Gpx::Writer::writeEndRoute()
     m_writer.writeEndElement();
 }
 
+void Gpx::Writer::writeStartWaypoint(float latitude, float longitude)
+{
+    m_writer.writeStartElement(QStringLiteral("wpt"));
+    m_writer.writeAttribute(QStringLiteral("lat"), QString::number(latitude));
+    m_writer.writeAttribute(QStringLiteral("lon"), QString::number(longitude));
+}
+
+void Gpx::Writer::writeEndWaypoint()
+{
+    m_writer.writeEndElement();
+}
+
 void Gpx::Writer::writeStartRoutePoint(float latitude, float longitude)
 {
     m_writer.writeStartElement(QStringLiteral("rtept"));

src/gpx/gpxwriter.h

@@ -29,6 +29,9 @@ public:
     void writeStartRoute();
     void writeEndRoute();
 
+    void writeStartWaypoint(float latitude, float longitude);
+    void writeEndWaypoint();
+
     void writeStartRoutePoint(float latitude, float longitude);
     void writeEndRoutePoint();