001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.gui.history;
003
004import static org.openstreetmap.josm.tools.I18n.tr;
005
006import java.awt.Dimension;
007import java.awt.Point;
008import java.util.ArrayList;
009import java.util.Collection;
010import java.util.HashMap;
011import java.util.Iterator;
012import java.util.List;
013import java.util.Map;
014import java.util.Map.Entry;
015import java.util.Objects;
016import java.util.function.Predicate;
017
018import javax.swing.JOptionPane;
019import javax.swing.SwingUtilities;
020
021import org.openstreetmap.josm.Main;
022import org.openstreetmap.josm.data.osm.PrimitiveId;
023import org.openstreetmap.josm.data.osm.history.History;
024import org.openstreetmap.josm.data.osm.history.HistoryDataSet;
025import org.openstreetmap.josm.gui.MainApplication;
026import org.openstreetmap.josm.gui.layer.LayerManager.LayerAddEvent;
027import org.openstreetmap.josm.gui.layer.LayerManager.LayerChangeListener;
028import org.openstreetmap.josm.gui.layer.LayerManager.LayerOrderChangeEvent;
029import org.openstreetmap.josm.gui.layer.LayerManager.LayerRemoveEvent;
030import org.openstreetmap.josm.gui.util.WindowGeometry;
031import org.openstreetmap.josm.tools.JosmRuntimeException;
032import org.openstreetmap.josm.tools.SubclassFilteredCollection;
033import org.openstreetmap.josm.tools.bugreport.BugReportExceptionHandler;
034
035/**
036 * Manager allowing to show/hide history dialogs.
037 * @since 2019
038 */
039public final class HistoryBrowserDialogManager implements LayerChangeListener {
040
041    static final class UnloadedHistoryPredicate implements Predicate<PrimitiveId> {
042        private final HistoryDataSet hds = HistoryDataSet.getInstance();
043
044        @Override
045        public boolean test(PrimitiveId p) {
046            History h = hds.getHistory(p);
047            if (h == null)
048                // reload if the history is not in the cache yet
049                return true;
050            else
051                // reload if the history object of the selected object is not in the cache yet
052                return !p.isNew() && h.getByVersion(p.getUniqueId()) == null;
053        }
054    }
055
056    private static final String WINDOW_GEOMETRY_PREF = HistoryBrowserDialogManager.class.getName() + ".geometry";
057
058    private static HistoryBrowserDialogManager instance;
059
060    private final Map<Long, HistoryBrowserDialog> dialogs;
061
062    private final Predicate<PrimitiveId> unloadedHistoryPredicate = new UnloadedHistoryPredicate();
063
064    private final Predicate<PrimitiveId> notNewPredicate = p -> !p.isNew();
065
066    protected HistoryBrowserDialogManager() {
067        dialogs = new HashMap<>();
068        MainApplication.getLayerManager().addLayerChangeListener(this);
069    }
070
071    /**
072     * Replies the unique instance.
073     * @return the unique instance
074     */
075    public static synchronized HistoryBrowserDialogManager getInstance() {
076        if (instance == null) {
077            instance = new HistoryBrowserDialogManager();
078        }
079        return instance;
080    }
081
082    /**
083     * Determines if an history dialog exists for the given object id.
084     * @param id the object id
085     * @return {@code true} if an history dialog exists for the given object id, {@code false} otherwise
086     */
087    public boolean existsDialog(long id) {
088        return dialogs.containsKey(id);
089    }
090
091    private void show(long id, HistoryBrowserDialog dialog) {
092        if (dialogs.containsValue(dialog)) {
093            show(id);
094        } else {
095            placeOnScreen(dialog);
096            dialog.setVisible(true);
097            dialogs.put(id, dialog);
098        }
099    }
100
101    private void show(long id) {
102        if (dialogs.containsKey(id)) {
103            dialogs.get(id).toFront();
104        }
105    }
106
107    private boolean hasDialogWithCloseUpperLeftCorner(Point p) {
108        for (HistoryBrowserDialog dialog: dialogs.values()) {
109            Point corner = dialog.getLocation();
110            if (p.x >= corner.x -5 && corner.x + 5 >= p.x
111                    && p.y >= corner.y -5 && corner.y + 5 >= p.y)
112                return true;
113        }
114        return false;
115    }
116
117    private void placeOnScreen(HistoryBrowserDialog dialog) {
118        WindowGeometry geometry = new WindowGeometry(WINDOW_GEOMETRY_PREF, WindowGeometry.centerOnScreen(new Dimension(850, 500)));
119        geometry.applySafe(dialog);
120        Point p = dialog.getLocation();
121        while (hasDialogWithCloseUpperLeftCorner(p)) {
122            p.x += 20;
123            p.y += 20;
124        }
125        dialog.setLocation(p);
126    }
127
128    /**
129     * Hides the specified history dialog and cleans associated resources.
130     * @param dialog History dialog to hide
131     */
132    public void hide(HistoryBrowserDialog dialog) {
133        for (Iterator<Entry<Long, HistoryBrowserDialog>> it = dialogs.entrySet().iterator(); it.hasNext();) {
134            if (Objects.equals(it.next().getValue(), dialog)) {
135                it.remove();
136                if (dialogs.isEmpty()) {
137                    new WindowGeometry(dialog).remember(WINDOW_GEOMETRY_PREF);
138                }
139                break;
140            }
141        }
142        dialog.setVisible(false);
143        dialog.dispose();
144    }
145
146    /**
147     * Hides and destroys all currently visible history browser dialogs
148     *
149     */
150    public void hideAll() {
151        List<HistoryBrowserDialog> dialogs = new ArrayList<>();
152        dialogs.addAll(this.dialogs.values());
153        for (HistoryBrowserDialog dialog: dialogs) {
154            dialog.unlinkAsListener();
155            hide(dialog);
156        }
157    }
158
159    /**
160     * Show history dialog for the given history.
161     * @param h History to show
162     */
163    public void show(History h) {
164        if (h == null)
165            return;
166        if (existsDialog(h.getId())) {
167            show(h.getId());
168        } else {
169            HistoryBrowserDialog dialog = new HistoryBrowserDialog(h);
170            show(h.getId(), dialog);
171        }
172    }
173
174    /* ----------------------------------------------------------------------------- */
175    /* LayerChangeListener                                                           */
176    /* ----------------------------------------------------------------------------- */
177    @Override
178    public void layerAdded(LayerAddEvent e) {
179        // Do nothing
180    }
181
182    @Override
183    public void layerRemoving(LayerRemoveEvent e) {
184        // remove all history browsers if the number of layers drops to 0
185        if (e.getSource().getLayers().isEmpty()) {
186            hideAll();
187        }
188    }
189
190    @Override
191    public void layerOrderChanged(LayerOrderChangeEvent e) {
192        // Do nothing
193    }
194
195    /**
196     * Show history dialog(s) for the given primitive(s).
197     * @param primitives The primitive(s) for which history will be displayed
198     */
199    public void showHistory(final Collection<? extends PrimitiveId> primitives) {
200        final Collection<? extends PrimitiveId> notNewPrimitives = SubclassFilteredCollection.filter(primitives, notNewPredicate);
201        if (notNewPrimitives.isEmpty()) {
202            JOptionPane.showMessageDialog(
203                    Main.parent,
204                    tr("Please select at least one already uploaded node, way, or relation."),
205                    tr("Warning"),
206                    JOptionPane.WARNING_MESSAGE);
207            return;
208        }
209
210        Collection<? extends PrimitiveId> toLoad = SubclassFilteredCollection.filter(primitives, unloadedHistoryPredicate);
211        if (!toLoad.isEmpty()) {
212            HistoryLoadTask task = new HistoryLoadTask();
213            for (PrimitiveId p : notNewPrimitives) {
214                task.add(p);
215            }
216            MainApplication.worker.submit(task);
217        }
218
219        Runnable r = () -> {
220            try {
221                for (PrimitiveId p : notNewPrimitives) {
222                    final History h = HistoryDataSet.getInstance().getHistory(p);
223                    if (h == null) {
224                        continue;
225                    }
226                    SwingUtilities.invokeLater(() -> show(h));
227                }
228            } catch (final JosmRuntimeException | IllegalArgumentException | IllegalStateException e) {
229                BugReportExceptionHandler.handleException(e);
230            }
231        };
232        MainApplication.worker.submit(r);
233    }
234}