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.io.importexport.GpxImporter;
017import org.openstreetmap.josm.gui.layer.GpxLayer;
018import org.openstreetmap.josm.gui.layer.Layer;
019import org.openstreetmap.josm.gui.layer.markerlayer.MarkerLayer;
020import org.openstreetmap.josm.gui.progress.ProgressMonitor;
021import org.openstreetmap.josm.io.IllegalDataException;
022import org.openstreetmap.josm.io.session.SessionReader.ImportSupport;
023import org.w3c.dom.Element;
024
025/**
026 * Session importer for {@link MarkerLayer}.
027 * @since 5684
028 */
029public class MarkerSessionImporter implements SessionLayerImporter {
030
031    @Override
032    public Layer load(Element elem, ImportSupport support, ProgressMonitor progressMonitor) throws IOException, IllegalDataException {
033        String version = elem.getAttribute("version");
034        if (!"0.1".equals(version)) {
035            throw new IllegalDataException(tr("Version ''{0}'' of meta data for marker layer is not supported. Expected: 0.1", version));
036        }
037        try {
038            XPathFactory xPathFactory = XPathFactory.newInstance();
039            XPath xpath = xPathFactory.newXPath();
040            XPathExpression fileExp = xpath.compile("file/text()");
041            String fileStr = (String) fileExp.evaluate(elem, XPathConstants.STRING);
042            if (fileStr == null || fileStr.isEmpty()) {
043                throw new IllegalDataException(tr("File name expected for layer no. {0}", support.getLayerIndex()));
044            }
045
046            try (InputStream in = support.getInputStream(fileStr)) {
047                GpxImporter.GpxImporterData importData = GpxImporter.loadLayers(in, support.getFile(fileStr), support.getLayerName(),
048                        null, progressMonitor);
049
050                support.addPostLayersTask(importData.getPostLayerTask());
051
052                GpxLayer gpxLayer = null;
053                List<SessionReader.LayerDependency> deps = support.getLayerDependencies();
054                if (!deps.isEmpty()) {
055                    Layer layer = deps.get(0).getLayer();
056                    if (layer instanceof GpxLayer) {
057                        gpxLayer = (GpxLayer) layer;
058                    }
059                }
060
061                MarkerLayer markerLayer = importData.getMarkerLayer();
062                if (markerLayer != null) {
063                    markerLayer.fromLayer = gpxLayer;
064                }
065
066                return markerLayer;
067            }
068        } catch (XPathExpressionException e) {
069            throw new IllegalDataException(e);
070        }
071    }
072}