source: osm/applications/editors/josm/plugins/osmarender/src/OsmarenderPlugin.java@ 12588

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

import java.awt.event.ActionEvent;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.BufferedReader;
import java.io.FileReader;
import java.util.Collection;
import java.util.HashSet;

import javax.swing.AbstractAction;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.JTextField;

import org.openstreetmap.josm.Main;
import org.openstreetmap.josm.data.Bounds;
import org.openstreetmap.josm.data.coor.LatLon;
import org.openstreetmap.josm.data.osm.DataSet;
import org.openstreetmap.josm.data.osm.Node;
import org.openstreetmap.josm.data.osm.Way;
import org.openstreetmap.josm.data.osm.OsmPrimitive;
import org.openstreetmap.josm.data.osm.visitor.CollectBackReferencesVisitor;
import org.openstreetmap.josm.gui.MapFrame;
import org.openstreetmap.josm.gui.preferences.PreferenceDialog;
import org.openstreetmap.josm.gui.preferences.PreferenceSetting;
import org.openstreetmap.josm.io.OsmWriter;
import org.openstreetmap.josm.plugins.Plugin;
import org.openstreetmap.josm.tools.GBC;

public class OsmarenderPlugin extends Plugin {

        private class Action extends AbstractAction {

                public Action() {
                        super("Osmarender");
                }

                public void actionPerformed(ActionEvent e) {
                        // get all stuff visible on screen
                        LatLon bottomLeft = Main.map.mapView.getLatLon(0,Main.map.mapView.getHeight());
                        LatLon topRight = Main.map.mapView.getLatLon(Main.map.mapView.getWidth(), 0);
                        Bounds b = new Bounds(bottomLeft, topRight);

                        try {
                                writeGenerated(b);
                        } catch(Exception ex) {
                                //how handle the exception?
                        }

                        CollectBackReferencesVisitor backRefsV = new CollectBackReferencesVisitor(Main.ds, true);
                        DataSet fromDataSet = new DataSet();
                        for (Node n : Main.ds.nodes) {
                                if (n.deleted || n.incomplete) continue;
                                if (n.coor.isWithin(b)) {
                                        fromDataSet.nodes.add(n);
                                        n.visit(backRefsV);
                                }
                        }
                        for (OsmPrimitive p : new HashSet<OsmPrimitive>(backRefsV.data)) {
                                if (p instanceof Way) {
                                        backRefsV.data.addAll(((Way) p).nodes);
                                }
                        }
                        for (OsmPrimitive p : backRefsV.data)
                                fromDataSet.addPrimitive(p);

                        String firefox = Main.pref.get("osmarender.firefox", "firefox");
                        try {
                                // write to plugin dir
                                OsmWriter.output(new FileOutputStream(getPluginDir()+"data.osm"), new OsmWriter.All(fromDataSet, true));

                                // get the exec line
                                String exec = firefox;
                                if (System.getProperty("os.name").startsWith("Windows"))
                                        exec += " file:///"+getPluginDir().replace('\\','/').replace(" ","%20")+"generated.xml\"";
                                else
                                        exec += " "+getPluginDir()+"generated.xml";

                                // launch up the viewer
                                Runtime.getRuntime().exec(exec);
                        } catch (IOException e1) {
                                JOptionPane.showMessageDialog(Main.parent, tr("Firefox not found. Please set firefox executable in the Map Settings page of the preferences."));
                        }
                }
        }

        private JMenu view;
        private JMenuItem osmarenderMenu = new JMenuItem(new Action());

        public OsmarenderPlugin() throws IOException {
                JMenuBar menu = Main.main.menu;
                view = null;
                for (int i = 0; i < menu.getMenuCount(); ++i) {
                        if (menu.getMenu(i) != null && tr("View").equals(menu.getMenu(i).getText())) {
                                view = menu.getMenu(i);
                                break;
                        }
                }
                if (view == null) {
                        view = new JMenu(tr("View"));
                        menu.add(view, 2);
                        view.setVisible(false);
                }
                view.add(osmarenderMenu);
                osmarenderMenu.setVisible(false);

                // install the xsl and xml file
                copy("/osmarender.xsl", "osmarender.xsl");
                copy("/osm-map-features.xml", "osm-map-features.xml");
        }

        @Override
        public void mapFrameInitialized(MapFrame oldFrame, MapFrame newFrame) {
                if (oldFrame != null && newFrame == null) {
                        // disable
                        osmarenderMenu.setVisible(false);
                        if (view.getMenuComponentCount() == 1)
                                view.setVisible(false);
                } else if (oldFrame == null && newFrame != null) {
                        // enable
                        osmarenderMenu.setVisible(true);
                        if (view.getMenuComponentCount() == 1)
                                view.setVisible(true);
                }
        }

        @Override public PreferenceSetting getPreferenceSetting() {
                return new PreferenceSetting(){
                        private JTextField firefox = new JTextField(10);
                        public void addGui(PreferenceDialog gui) {
                                gui.map.add(new JLabel(tr("osmarender options")), GBC.eol().insets(0,5,0,0));
                                gui.map.add(new JLabel(tr("Firefox executable")), GBC.std().insets(10,5,5,0));
                                gui.map.add(firefox, GBC.eol().insets(0,5,0,0).fill(GBC.HORIZONTAL));
                                firefox.setText(Main.pref.get("osmarender.firefox"));
                        }
                        public boolean ok() {
                                Main.pref.put("osmarender.firefox", firefox.getText());
                                return false;
                        }
                };
        }

        private void writeGenerated(Bounds b) throws IOException {
                String bounds_tag = "<bounds " +
                        "minlat=\"" + b.min.lat() + "\" " +
                        "maxlat=\"" + b.max.lat() + "\" " +
                        "minlon=\"" + b.min.lon() + "\" " +
                        "maxlon=\"" + b.max.lon() + "\" " + "/>";

                BufferedReader reader = new BufferedReader(
                                new FileReader( getPluginDir() + "osm-map-features.xml") );
                PrintWriter writer = new PrintWriter( getPluginDir() + "generated.xml");

                // osm-map-fetaures.xml contain two placemark
                // (bounds_mkr1 and bounds_mkr2). We write the bounds tag
                // between the two
                String str = null;
                while( (str = reader.readLine()) != null ) {
                        if(str.contains("<!--bounds_mkr1-->")) {
                                writer.println(str);
                                writer.println("    " + bounds_tag);
                                while(!str.contains("<!--bounds_mkr2-->")) {
                                        str = reader.readLine();
                                }
                                writer.println(str);
                        } else {
                                writer.println(str);
                        }
                }

                writer.close();
        }
}