// License: GPL. For details, see LICENSE file.
package org.openstreetmap.josm.io;

import static org.openstreetmap.josm.tools.I18n.tr;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;

import javax.swing.JOptionPane;

import org.openstreetmap.josm.Main;
import org.openstreetmap.josm.actions.ExtensionFileFilter;
import org.openstreetmap.josm.data.gpx.GpxData;
import org.openstreetmap.josm.gui.layer.GpxLayer;
import org.openstreetmap.josm.gui.layer.markerlayer.MarkerLayer;
import org.openstreetmap.josm.gui.progress.ProgressMonitor;
import org.openstreetmap.josm.gui.util.GuiHelper;
import org.xml.sax.SAXException;

/**
 * File importer allowing to import GPX files (*.gpx/gpx.gz files).
 *
 */
public class GpxImporter extends FileImporter {

    /**
     * The GPX file filter (*.gpx and *.gpx.gz files).
     */
    public static final ExtensionFileFilter FILE_FILTER = new ExtensionFileFilter(
            "gpx,gpx.gz,gpx.bz2", "gpx", tr("GPX Files") + " (*.gpx *.gpx.gz, *.gpx.bz2)");

    /**
     * Utility class containing imported GPX and marker layers, and a task to run after they are added to MapView.
     */
    public static class GpxImporterData {
        /**
         * The imported GPX layer. May be null if no GPX data.
         */
        private GpxLayer gpxLayer;
        /**
         * The imported marker layer. May be null if no marker.
         */
        private MarkerLayer markerLayer;
        /**
         * The task to run after GPX and/or marker layer has been added to MapView.
         */
        private Runnable postLayerTask;

        public GpxImporterData(GpxLayer gpxLayer, MarkerLayer markerLayer, Runnable postLayerTask) {
            this.gpxLayer = gpxLayer;
            this.markerLayer = markerLayer;
            this.postLayerTask = postLayerTask;
        }

        public GpxLayer getGpxLayer() {
            return gpxLayer;
        }

        public MarkerLayer getMarkerLayer() {
            return markerLayer;
        }

        public Runnable getPostLayerTask() {
            return postLayerTask;
        }
    }

    /**
     * Constructs a new {@code GpxImporter}.
     */
    public GpxImporter() {
        super(FILE_FILTER);
    }

    @Override
    public void importData(File file, ProgressMonitor progressMonitor) throws IOException {
        final String fileName = file.getName();

        try (InputStream is = Compression.getUncompressedFileInputStream(file)) {
            GpxReader r = new GpxReader(is);
            boolean parsedProperly = r.parse(true);
            r.getGpxData().storageFile = file;
            addLayers(loadLayers(r.getGpxData(), parsedProperly, fileName, tr("Markers from {0}", fileName)));
        } catch (SAXException e) {
            Main.error(e);
            throw new IOException(tr("Parsing data for layer ''{0}'' failed", fileName), e);
        }
    }

    /**
     * Adds the specified GPX and marker layers to Map.main
     * @param data The layers to add
     * @see #loadLayers
     */
    public static void addLayers(final GpxImporterData data) {
        // FIXME: remove UI stuff from the IO subsystem
        GuiHelper.runInEDT(new Runnable() {
            @Override
            public void run() {
                if (data.markerLayer != null) {
                    Main.main.addLayer(data.markerLayer);
                }
                if (data.gpxLayer != null) {
                    Main.main.addLayer(data.gpxLayer);
                }
                data.postLayerTask.run();
            }
        });
    }

    /**
     * Replies the new GPX and marker layers corresponding to the specified GPX data.
     * @param data The GPX data
     * @param parsedProperly True if GPX data has been properly parsed by {@link GpxReader#parse}
     * @param gpxLayerName The GPX layer name
     * @param markerLayerName The marker layer name
     * @return the new GPX and marker layers corresponding to the specified GPX data, to be used with {@link #addLayers}
     * @see #addLayers
     */
    public static GpxImporterData loadLayers(final GpxData data, final boolean parsedProperly,
            final String gpxLayerName, String markerLayerName) {
        GpxLayer gpxLayer = null;
        MarkerLayer markerLayer = null;
        if (data.hasRoutePoints() || data.hasTrackPoints()) {
            gpxLayer = new GpxLayer(data, gpxLayerName, data.storageFile != null);
        }
        if (Main.pref.getBoolean("marker.makeautomarkers", true) && !data.waypoints.isEmpty()) {
            markerLayer = new MarkerLayer(data, markerLayerName, data.storageFile, gpxLayer);
            if (markerLayer.data.isEmpty()) {
                markerLayer = null;
            }
        }
        Runnable postLayerTask = new Runnable() {
            @Override
            public void run() {
                if (!parsedProperly) {
                    String msg;
                    if (data.storageFile == null) {
                        msg = tr("Error occurred while parsing gpx data for layer ''{0}''. Only a part of the file will be available.",
                                gpxLayerName);
                    } else {
                        msg = tr("Error occurred while parsing gpx file ''{0}''. Only a part of the file will be available.",
                                data.storageFile.getPath());
                    }
                    JOptionPane.showMessageDialog(null, msg);
                }
            }
        };
        return new GpxImporterData(gpxLayer, markerLayer, postLayerTask);
    }

    public static GpxImporterData loadLayers(InputStream is, final File associatedFile,
            final String gpxLayerName, String markerLayerName, ProgressMonitor progressMonitor) throws IOException {
        try {
            final GpxReader r = new GpxReader(is);
            final boolean parsedProperly = r.parse(true);
            r.getGpxData().storageFile = associatedFile;
            return loadLayers(r.getGpxData(), parsedProperly, gpxLayerName, markerLayerName);
        } catch (SAXException e) {
            Main.error(e);
            throw new IOException(tr("Parsing data for layer ''{0}'' failed", gpxLayerName), e);
        }
    }
}