001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.gui;
003
004import static org.openstreetmap.josm.tools.I18n.tr;
005
006import java.awt.BasicStroke;
007import java.awt.Color;
008import java.awt.Component;
009import java.awt.Container;
010import java.awt.Dimension;
011import java.awt.Graphics;
012import java.awt.Graphics2D;
013import java.awt.Insets;
014import java.awt.Point;
015import java.awt.RenderingHints;
016import java.awt.Shape;
017import java.awt.event.ActionEvent;
018import java.awt.event.ActionListener;
019import java.awt.event.MouseAdapter;
020import java.awt.event.MouseEvent;
021import java.awt.event.MouseListener;
022import java.awt.geom.RoundRectangle2D;
023import java.util.Deque;
024import java.util.LinkedList;
025import java.util.Objects;
026
027import javax.swing.AbstractAction;
028import javax.swing.BorderFactory;
029import javax.swing.GroupLayout;
030import javax.swing.JButton;
031import javax.swing.JFrame;
032import javax.swing.JLabel;
033import javax.swing.JLayeredPane;
034import javax.swing.JPanel;
035import javax.swing.JToolBar;
036import javax.swing.SwingUtilities;
037import javax.swing.Timer;
038
039import org.openstreetmap.josm.data.preferences.IntegerProperty;
040import org.openstreetmap.josm.gui.help.HelpBrowser;
041import org.openstreetmap.josm.gui.help.HelpUtil;
042import org.openstreetmap.josm.gui.util.GuiHelper;
043import org.openstreetmap.josm.tools.ImageProvider;
044import org.openstreetmap.josm.tools.Logging;
045
046/**
047 * Manages {@link Notification}s, i.e. displays them on screen.
048 *
049 * Don't use this class directly, but use {@link Notification#show()}.
050 *
051 * If multiple messages are sent in a short period of time, they are put in
052 * a queue and displayed one after the other.
053 *
054 * The user can stop the timer (freeze the message) by moving the mouse cursor
055 * above the panel. As a visual cue, the background color changes from
056 * semi-transparent to opaque while the timer is frozen.
057 */
058class NotificationManager {
059
060    private final Timer hideTimer; // started when message is shown, responsible for hiding the message
061    private final Timer pauseTimer; // makes sure, there is a small pause between two consecutive messages
062    private final Timer unfreezeDelayTimer; // tiny delay before resuming the timer when mouse cursor is moved off the panel
063    private boolean running;
064
065    private Notification currentNotification;
066    private NotificationPanel currentNotificationPanel;
067    private final Deque<Notification> queue;
068
069    private static final IntegerProperty pauseTime = new IntegerProperty("notification-default-pause-time-ms", 300); // milliseconds
070
071    private long displayTimeStart;
072    private long elapsedTime;
073
074    private static NotificationManager instance;
075
076    private static final Color PANEL_SEMITRANSPARENT = new Color(224, 236, 249, 230);
077    private static final Color PANEL_OPAQUE = new Color(224, 236, 249);
078
079    NotificationManager() {
080        queue = new LinkedList<>();
081        hideTimer = new Timer(Notification.TIME_DEFAULT, e -> this.stopHideTimer());
082        hideTimer.setRepeats(false);
083        pauseTimer = new Timer(pauseTime.get(), new PauseFinishedEvent());
084        pauseTimer.setRepeats(false);
085        unfreezeDelayTimer = new Timer(10, new UnfreezeEvent());
086        unfreezeDelayTimer.setRepeats(false);
087    }
088
089    /**
090     * Show the given notification (unless a duplicate notification is being shown at the moment or at the end of the queue)
091     * @param note The note to show.
092     * @see Notification#show()
093     */
094    void showNotification(Notification note) {
095        synchronized (queue) {
096            if (Objects.equals(note, currentNotification) || Objects.equals(note, queue.peekLast())) {
097                Logging.debug("Dropping duplicate notification {0}", note);
098                return;
099            }
100            queue.add(note);
101            processQueue();
102        }
103    }
104
105    /**
106     * Show the given notification by replacing the given queued/displaying notification
107     * @param oldNotification the notification to replace
108     * @param newNotification the notification to show
109     */
110    void replaceExistingNotification(Notification oldNotification, Notification newNotification) {
111        synchronized (queue) {
112            if (Objects.equals(oldNotification, currentNotification)) {
113                stopHideTimer();
114            } else {
115                queue.remove(oldNotification);
116            }
117            showNotification(newNotification);
118            processQueue();
119        }
120    }
121
122    private void processQueue() {
123        if (running) return;
124
125        currentNotification = queue.poll();
126        if (currentNotification == null) return;
127
128        GuiHelper.runInEDTAndWait(() -> {
129            currentNotificationPanel = new NotificationPanel(currentNotification, new FreezeMouseListener(), e -> this.stopHideTimer());
130            currentNotificationPanel.validate();
131
132            int margin = 5;
133            JFrame parentWindow = MainApplication.getMainFrame();
134            Dimension size = currentNotificationPanel.getPreferredSize();
135            if (parentWindow != null) {
136                int x;
137                int y;
138                MapFrame map = MainApplication.getMap();
139                if (MainApplication.isDisplayingMapView() && map.mapView.getHeight() > 0) {
140                    MapView mv = map.mapView;
141                    Point mapViewPos = SwingUtilities.convertPoint(mv.getParent(), mv.getX(), mv.getY(), MainApplication.getMainFrame());
142                    x = mapViewPos.x + margin;
143                    y = mapViewPos.y + mv.getHeight() - map.statusLine.getHeight() - size.height - margin;
144                } else {
145                    x = margin;
146                    y = parentWindow.getHeight() - MainApplication.getToolbar().control.getSize().height - size.height - margin;
147                }
148                parentWindow.getLayeredPane().add(currentNotificationPanel, JLayeredPane.POPUP_LAYER, 0);
149
150                currentNotificationPanel.setLocation(x, y);
151            }
152            currentNotificationPanel.setSize(size);
153            currentNotificationPanel.setVisible(true);
154        });
155
156        running = true;
157        elapsedTime = 0;
158
159        startHideTimer();
160    }
161
162    private void startHideTimer() {
163        int remaining = (int) (currentNotification.getDuration() - elapsedTime);
164        if (remaining < 300) {
165            remaining = 300;
166        }
167        displayTimeStart = System.currentTimeMillis();
168        hideTimer.setInitialDelay(remaining);
169        hideTimer.restart();
170    }
171
172    private void stopHideTimer() {
173        hideTimer.stop();
174        if (currentNotificationPanel != null) {
175            currentNotificationPanel.setVisible(false);
176            JFrame parent = MainApplication.getMainFrame();
177            if (parent != null) {
178                parent.getLayeredPane().remove(currentNotificationPanel);
179            }
180            currentNotificationPanel = null;
181        }
182        pauseTimer.restart();
183    }
184
185    private class PauseFinishedEvent implements ActionListener {
186
187        @Override
188        public void actionPerformed(ActionEvent e) {
189            synchronized (queue) {
190                running = false;
191                processQueue();
192            }
193        }
194    }
195
196    private class UnfreezeEvent implements ActionListener {
197
198        @Override
199        public void actionPerformed(ActionEvent e) {
200            if (currentNotificationPanel != null) {
201                currentNotificationPanel.setNotificationBackground(PANEL_SEMITRANSPARENT);
202                currentNotificationPanel.repaint();
203            }
204            startHideTimer();
205        }
206    }
207
208    private static class NotificationPanel extends JPanel {
209
210        static final class ShowNoteHelpAction extends AbstractAction {
211            private final Notification note;
212
213            ShowNoteHelpAction(Notification note) {
214                super(tr("Help"));
215                putValue(SHORT_DESCRIPTION, tr("Show help information"));
216                new ImageProvider("help").getResource().attachImageIcon(this, true);
217                this.note = note;
218            }
219
220            @Override
221            public void actionPerformed(ActionEvent e) {
222                SwingUtilities.invokeLater(() -> HelpBrowser.setUrlForHelpTopic(note.getHelpTopic()));
223            }
224        }
225
226        private JPanel innerPanel;
227
228        NotificationPanel(Notification note, MouseListener freeze, ActionListener hideListener) {
229            setVisible(false);
230            build(note, freeze, hideListener);
231        }
232
233        public void setNotificationBackground(Color c) {
234            innerPanel.setBackground(c);
235        }
236
237        private void build(final Notification note, MouseListener freeze, ActionListener hideListener) {
238            JButton btnClose = new JButton();
239            btnClose.addActionListener(hideListener);
240            btnClose.setIcon(ImageProvider.get("misc", "grey_x"));
241            btnClose.setPreferredSize(new Dimension(50, 50));
242            btnClose.setMargin(new Insets(0, 0, 1, 1));
243            btnClose.setContentAreaFilled(false);
244            // put it in JToolBar to get a better appearance
245            JToolBar tbClose = new JToolBar();
246            tbClose.setFloatable(false);
247            tbClose.setBorderPainted(false);
248            tbClose.setOpaque(false);
249            tbClose.add(btnClose);
250
251            JToolBar tbHelp = null;
252            if (note.getHelpTopic() != null) {
253                JButton btnHelp = new JButton(new ShowNoteHelpAction(note));
254                HelpUtil.setHelpContext(btnHelp, note.getHelpTopic());
255                btnHelp.setOpaque(false);
256                tbHelp = new JToolBar();
257                tbHelp.setFloatable(false);
258                tbHelp.setBorderPainted(false);
259                tbHelp.setOpaque(false);
260                tbHelp.add(btnHelp);
261            }
262
263            setOpaque(false);
264            innerPanel = new RoundedPanel();
265            innerPanel.setBackground(PANEL_SEMITRANSPARENT);
266            innerPanel.setForeground(Color.BLACK);
267
268            GroupLayout layout = new GroupLayout(innerPanel);
269            innerPanel.setLayout(layout);
270            layout.setAutoCreateGaps(true);
271            layout.setAutoCreateContainerGaps(true);
272
273            innerPanel.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
274            add(innerPanel);
275
276            JLabel icon = null;
277            if (note.getIcon() != null) {
278                icon = new JLabel(note.getIcon());
279            }
280            Component content = note.getContent();
281            GroupLayout.SequentialGroup hgroup = layout.createSequentialGroup();
282            if (icon != null) {
283                hgroup.addComponent(icon);
284            }
285            if (tbHelp != null) {
286                hgroup.addGroup(layout.createParallelGroup(GroupLayout.Alignment.TRAILING)
287                        .addComponent(content)
288                        .addComponent(tbHelp)
289                );
290            } else {
291                hgroup.addComponent(content);
292            }
293            hgroup.addComponent(tbClose);
294            GroupLayout.ParallelGroup vgroup = layout.createParallelGroup();
295            if (icon != null) {
296                vgroup.addComponent(icon);
297            }
298            vgroup.addComponent(content);
299            vgroup.addComponent(tbClose);
300            layout.setHorizontalGroup(hgroup);
301
302            if (tbHelp != null) {
303                layout.setVerticalGroup(layout.createSequentialGroup()
304                        .addGroup(vgroup)
305                        .addComponent(tbHelp)
306                );
307            } else {
308                layout.setVerticalGroup(vgroup);
309            }
310
311            /*
312             * The timer stops when the mouse cursor is above the panel.
313             *
314             * This is not straightforward, because the JPanel will get a
315             * mouseExited event when the cursor moves on top of the JButton
316             * inside the panel.
317             *
318             * The current hacky solution is to register the freeze MouseListener
319             * not only to the panel, but to all the components inside the panel.
320             *
321             * Moving the mouse cursor from one component to the next would
322             * cause some flickering (timer is started and stopped for a fraction
323             * of a second, background color is switched twice), so there is
324             * a tiny delay before the timer really resumes.
325             */
326            addMouseListenerToAllChildComponents(this, freeze);
327        }
328
329        private static void addMouseListenerToAllChildComponents(Component comp, MouseListener listener) {
330            comp.addMouseListener(listener);
331            if (comp instanceof Container) {
332                for (Component c: ((Container) comp).getComponents()) {
333                    addMouseListenerToAllChildComponents(c, listener);
334                }
335            }
336        }
337    }
338
339    class FreezeMouseListener extends MouseAdapter {
340        @Override
341        public void mouseEntered(MouseEvent e) {
342            if (unfreezeDelayTimer.isRunning()) {
343                unfreezeDelayTimer.stop();
344            } else {
345                hideTimer.stop();
346                elapsedTime += System.currentTimeMillis() - displayTimeStart;
347                currentNotificationPanel.setNotificationBackground(PANEL_OPAQUE);
348                currentNotificationPanel.repaint();
349            }
350        }
351
352        @Override
353        public void mouseExited(MouseEvent e) {
354            unfreezeDelayTimer.restart();
355        }
356    }
357
358    /**
359     * A panel with rounded edges and line border.
360     */
361    public static class RoundedPanel extends JPanel {
362
363        RoundedPanel() {
364            super();
365            setOpaque(false);
366        }
367
368        @Override
369        protected void paintComponent(Graphics graphics) {
370            Graphics2D g = (Graphics2D) graphics;
371            g.setRenderingHint(
372                    RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
373            g.setColor(getBackground());
374            float lineWidth = 1.4f;
375            Shape rect = new RoundRectangle2D.Double(
376                    lineWidth/2d + getInsets().left,
377                    lineWidth/2d + getInsets().top,
378                    getWidth() - lineWidth/2d - getInsets().left - getInsets().right,
379                    getHeight() - lineWidth/2d - getInsets().top - getInsets().bottom,
380                    20, 20);
381
382            g.fill(rect);
383            g.setColor(getForeground());
384            g.setStroke(new BasicStroke(lineWidth));
385            g.draw(rect);
386            super.paintComponent(graphics);
387        }
388    }
389
390    public static synchronized NotificationManager getInstance() {
391        if (instance == null) {
392            instance = new NotificationManager();
393        }
394        return instance;
395    }
396}