001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.io.session;
003
004import static org.openstreetmap.josm.tools.I18n.tr;
005
006import java.io.IOException;
007import java.io.InputStream;
008import java.util.List;
009
010import javax.xml.xpath.XPath;
011import javax.xml.xpath.XPathConstants;
012import javax.xml.xpath.XPathExpression;
013import javax.xml.xpath.XPathExpressionException;
014import javax.xml.xpath.XPathFactory;
015
016import org.openstreetmap.josm.gui.layer.GpxLayer;
017import org.openstreetmap.josm.gui.layer.Layer;
018import org.openstreetmap.josm.gui.layer.markerlayer.MarkerLayer;
019import org.openstreetmap.josm.gui.progress.ProgressMonitor;
020import org.openstreetmap.josm.io.GpxImporter;
021import org.openstreetmap.josm.io.IllegalDataException;
022import org.openstreetmap.josm.io.session.SessionReader.ImportSupport;
023import org.w3c.dom.Element;
024
025public class MarkerSessionImporter implements SessionLayerImporter {
026
027    @Override
028    public Layer load(Element elem, ImportSupport support, ProgressMonitor progressMonitor) throws IOException, IllegalDataException {
029        String version = elem.getAttribute("version");
030        if (!"0.1".equals(version)) {
031            throw new IllegalDataException(tr("Version ''{0}'' of meta data for marker layer is not supported. Expected: 0.1", version));
032        }
033        try {
034            XPathFactory xPathFactory = XPathFactory.newInstance();
035            XPath xpath = xPathFactory.newXPath();
036            XPathExpression fileExp = xpath.compile("file/text()");
037            String fileStr = (String) fileExp.evaluate(elem, XPathConstants.STRING);
038            if (fileStr == null || fileStr.isEmpty()) {
039                throw new IllegalDataException(tr("File name expected for layer no. {0}", support.getLayerIndex()));
040            }
041
042            try (InputStream in = support.getInputStream(fileStr)) {
043                GpxImporter.GpxImporterData importData = GpxImporter.loadLayers(in, support.getFile(fileStr), support.getLayerName(), null, progressMonitor);
044
045                support.addPostLayersTask(importData.getPostLayerTask());
046
047                GpxLayer gpxLayer = null;
048                List<SessionReader.LayerDependency> deps = support.getLayerDependencies();
049                if (!deps.isEmpty()) {
050                    Layer layer = deps.iterator().next().getLayer();
051                    if (layer instanceof GpxLayer) {
052                        gpxLayer = (GpxLayer) layer;
053                    }
054                }
055
056                MarkerLayer markerLayer = importData.getMarkerLayer();
057                if (markerLayer != null) {
058                    markerLayer.fromLayer = gpxLayer;
059                }
060
061                return markerLayer;
062            }
063        } catch (XPathExpressionException e) {
064            throw new IllegalDataException(e);
065        }
066    }
067}