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