001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.io.session;
003
004import java.io.BufferedOutputStream;
005import java.io.File;
006import java.io.FileNotFoundException;
007import java.io.FileOutputStream;
008import java.io.IOException;
009import java.io.OutputStream;
010import java.io.OutputStreamWriter;
011import java.lang.reflect.Constructor;
012import java.nio.charset.StandardCharsets;
013import java.util.ArrayList;
014import java.util.HashMap;
015import java.util.List;
016import java.util.Map;
017import java.util.Set;
018import java.util.zip.ZipEntry;
019import java.util.zip.ZipOutputStream;
020
021import javax.xml.parsers.DocumentBuilder;
022import javax.xml.parsers.DocumentBuilderFactory;
023import javax.xml.parsers.ParserConfigurationException;
024import javax.xml.transform.OutputKeys;
025import javax.xml.transform.Transformer;
026import javax.xml.transform.TransformerException;
027import javax.xml.transform.TransformerFactory;
028import javax.xml.transform.dom.DOMSource;
029import javax.xml.transform.stream.StreamResult;
030
031import org.openstreetmap.josm.Main;
032import org.openstreetmap.josm.data.coor.EastNorth;
033import org.openstreetmap.josm.data.coor.LatLon;
034import org.openstreetmap.josm.data.projection.Projections;
035import org.openstreetmap.josm.gui.layer.GpxLayer;
036import org.openstreetmap.josm.gui.layer.Layer;
037import org.openstreetmap.josm.gui.layer.OsmDataLayer;
038import org.openstreetmap.josm.gui.layer.TMSLayer;
039import org.openstreetmap.josm.gui.layer.WMSLayer;
040import org.openstreetmap.josm.gui.layer.WMTSLayer;
041import org.openstreetmap.josm.gui.layer.geoimage.GeoImageLayer;
042import org.openstreetmap.josm.gui.layer.markerlayer.MarkerLayer;
043import org.openstreetmap.josm.tools.MultiMap;
044import org.openstreetmap.josm.tools.Utils;
045import org.w3c.dom.Document;
046import org.w3c.dom.Element;
047import org.w3c.dom.Text;
048
049public class SessionWriter {
050
051    private static Map<Class<? extends Layer>, Class<? extends SessionLayerExporter>> sessionLayerExporters = new HashMap<>();
052
053    static {
054        registerSessionLayerExporter(OsmDataLayer.class, OsmDataSessionExporter.class);
055        registerSessionLayerExporter(TMSLayer.class, ImagerySessionExporter.class);
056        registerSessionLayerExporter(WMSLayer.class, ImagerySessionExporter.class);
057        registerSessionLayerExporter(WMTSLayer.class, ImagerySessionExporter.class);
058        registerSessionLayerExporter(GpxLayer.class, GpxTracksSessionExporter.class);
059        registerSessionLayerExporter(GeoImageLayer.class, GeoImageSessionExporter.class);
060        registerSessionLayerExporter(MarkerLayer.class, MarkerSessionExporter.class);
061    }
062
063    /**
064     * Register a session layer exporter.
065     *
066     * The exporter class must have a one-argument constructor with layerClass as formal parameter type.
067     */
068    public static void registerSessionLayerExporter(Class<? extends Layer> layerClass, Class<? extends SessionLayerExporter> exporter) {
069        sessionLayerExporters.put(layerClass, exporter);
070    }
071
072    public static SessionLayerExporter getSessionLayerExporter(Layer layer) {
073        Class<? extends Layer> layerClass = layer.getClass();
074        Class<? extends SessionLayerExporter> exporterClass = sessionLayerExporters.get(layerClass);
075        if (exporterClass == null) return null;
076        try {
077            Constructor<? extends SessionLayerExporter> constructor = exporterClass.getConstructor(layerClass);
078            return constructor.newInstance(layer);
079        } catch (Exception e) {
080            throw new RuntimeException(e);
081        }
082    }
083
084    private final List<Layer> layers;
085    private final int active;
086    private final Map<Layer, SessionLayerExporter> exporters;
087    private final MultiMap<Layer, Layer> dependencies;
088    private final boolean zip;
089
090    private ZipOutputStream zipOut;
091
092    /**
093     * Constructs a new {@code SessionWriter}.
094     * @param layers The ordered list of layers to save
095     * @param active The index of active layer in {@code layers} (starts at 0). Ignored if set to -1
096     * @param exporters The exporters to use to save layers
097     * @param zip {@code true} if a joz archive has to be created, {@code false otherwise}
098     * @since 6271
099     */
100    public SessionWriter(List<Layer> layers, int active, Map<Layer, SessionLayerExporter> exporters,
101                MultiMap<Layer, Layer> dependencies, boolean zip) {
102        this.layers = layers;
103        this.active = active;
104        this.exporters = exporters;
105        this.dependencies = dependencies;
106        this.zip = zip;
107    }
108
109    /**
110     * A class that provides some context for the individual {@link SessionLayerExporter}
111     * when doing the export.
112     */
113    public class ExportSupport {
114        private Document doc;
115        private int layerIndex;
116
117        public ExportSupport(Document doc, int layerIndex) {
118            this.doc = doc;
119            this.layerIndex = layerIndex;
120        }
121
122        public Element createElement(String name) {
123            return doc.createElement(name);
124        }
125
126        public Text createTextNode(String text) {
127            return doc.createTextNode(text);
128        }
129
130        /**
131         * Get the index of the layer that is currently exported.
132         * @return the index of the layer that is currently exported
133         */
134        public int getLayerIndex() {
135            return layerIndex;
136        }
137
138        /**
139         * Create a file inside the zip archive.
140         *
141         * @param zipPath the path inside the zip archive, e.g. "layers/03/data.xml"
142         * @return the OutputStream you can write to. Never close the returned
143         * output stream, but make sure to flush buffers.
144         * @throws IOException if any I/O error occurs
145         */
146        public OutputStream getOutputStreamZip(String zipPath) throws IOException {
147            if (!isZip()) throw new RuntimeException();
148            ZipEntry entry = new ZipEntry(zipPath);
149            zipOut.putNextEntry(entry);
150            return zipOut;
151        }
152
153        /**
154         * Check, if the session is exported as a zip archive.
155         *
156         * @return true, if the session is exported as a zip archive (.joz file
157         * extension). It will always return true, if one of the
158         * {@link SessionLayerExporter} returns true for the
159         * {@link SessionLayerExporter#requiresZip()} method. Otherwise, the
160         * user can decide in the file chooser dialog.
161         */
162        public boolean isZip() {
163            return zip;
164        }
165    }
166
167    public Document createJosDocument() throws IOException {
168        DocumentBuilderFactory builderFactory = DocumentBuilderFactory.newInstance();
169        builderFactory.setValidating(false);
170        builderFactory.setNamespaceAware(true);
171        DocumentBuilder builder = null;
172        try {
173            builder = builderFactory.newDocumentBuilder();
174        } catch (ParserConfigurationException e) {
175            throw new RuntimeException(e);
176        }
177        Document doc = builder.newDocument();
178
179        Element root = doc.createElement("josm-session");
180        root.setAttribute("version", "0.1");
181        doc.appendChild(root);
182
183        Element viewportEl = doc.createElement("viewport");
184        root.appendChild(viewportEl);
185        Element centerEl = doc.createElement("center");
186        viewportEl.appendChild(centerEl);
187        EastNorth center = Main.map.mapView.getCenter();
188        LatLon centerLL = Projections.inverseProject(center);
189        centerEl.setAttribute("lat", Double.toString(centerLL.lat()));
190        centerEl.setAttribute("lon", Double.toString(centerLL.lon()));
191        Element scale = doc.createElement("scale");
192        viewportEl.appendChild(scale);
193        double dist100px = Main.map.mapView.getDist100Pixel();
194        scale.setAttribute("meter-per-pixel", Double.toString(dist100px / 100));
195
196        Element layersEl = doc.createElement("layers");
197        if (active >= 0) {
198            layersEl.setAttribute("active", Integer.toString(active+1));
199        }
200        root.appendChild(layersEl);
201
202        for (int index = 0; index < layers.size(); ++index) {
203            Layer layer = layers.get(index);
204            SessionLayerExporter exporter = exporters.get(layer);
205            ExportSupport support = new ExportSupport(doc, index+1);
206            Element el = exporter.export(support);
207            el.setAttribute("index", Integer.toString(index+1));
208            el.setAttribute("name", layer.getName());
209            el.setAttribute("visible", Boolean.toString(layer.isVisible()));
210            if (!Utils.equalsEpsilon(layer.getOpacity(), 1.0)) {
211                el.setAttribute("opacity", Double.toString(layer.getOpacity()));
212            }
213            Set<Layer> deps = dependencies.get(layer);
214            if (deps != null && !deps.isEmpty()) {
215                List<Integer> depsInt = new ArrayList<>();
216                for (Layer depLayer : deps) {
217                    int depIndex = layers.indexOf(depLayer);
218                    if (depIndex == -1) throw new AssertionError();
219                    depsInt.add(depIndex+1);
220                }
221                el.setAttribute("depends", Utils.join(",", depsInt));
222            }
223            layersEl.appendChild(el);
224        }
225        return doc;
226    }
227
228    public void writeJos(Document doc, OutputStream out) throws IOException {
229        try {
230            OutputStreamWriter writer = new OutputStreamWriter(out, StandardCharsets.UTF_8);
231            writer.write("<?xml version=\"1.0\" encoding=\"utf-8\"?>\n");
232            TransformerFactory transfac = TransformerFactory.newInstance();
233            Transformer trans = transfac.newTransformer();
234            trans.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
235            trans.setOutputProperty(OutputKeys.INDENT, "yes");
236            trans.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
237            StreamResult result = new StreamResult(writer);
238            DOMSource source = new DOMSource(doc);
239            trans.transform(source, result);
240        } catch (TransformerException e) {
241            throw new RuntimeException(e);
242        }
243    }
244
245    public void write(File f) throws IOException {
246        try (OutputStream out = new FileOutputStream(f)) {
247            write(out);
248        } catch (FileNotFoundException e) {
249            throw new IOException(e);
250        }
251    }
252
253    public void write(OutputStream out) throws IOException {
254        if (zip) {
255            zipOut = new ZipOutputStream(new BufferedOutputStream(out), StandardCharsets.UTF_8);
256        }
257        Document doc = createJosDocument(); // as side effect, files may be added to zipOut
258        if (zip) {
259            ZipEntry entry = new ZipEntry("session.jos");
260            zipOut.putNextEntry(entry);
261            writeJos(doc, zipOut);
262            Utils.close(zipOut);
263        } else {
264            writeJos(doc, new BufferedOutputStream(out));
265        }
266    }
267}