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