/**
   * Creates the buttons panel.
   *
   * @return the buttons panel
   */
  private Component createButtonsPanel() {
    JPanel buttonsPanel = new TransparentPanel(new FlowLayout(FlowLayout.RIGHT));

    JButton okButton = new JButton(GuiActivator.getResources().getI18NString("service.gui.OK"));

    okButton.addActionListener(
        new ActionListener() {
          public void actionPerformed(ActionEvent e) {
            selectedDevice = (MediaDevice) deviceComboBox.getSelectedItem();

            dispose();
          }
        });

    buttonsPanel.add(okButton);

    cancelButton.addActionListener(
        new ActionListener() {
          public void actionPerformed(ActionEvent e) {
            selectedDevice = null;
            dispose();
          }
        });

    buttonsPanel.add(cancelButton);

    return buttonsPanel;
  }
/**
 * A dialog dedicated to desktop streaming/sharing. Shows the possible screens to select from to use
 * for the streaming/sharing session.
 *
 * @author Yana Stamcheva
 */
public class SelectScreenDialog extends SIPCommDialog {
  /** Serial version UID. */
  private static final long serialVersionUID = 0L;

  /** The object used for logging. */
  private static final Logger logger = Logger.getLogger(SelectScreenDialog.class);

  /** The combo box containing screen choice. */
  private final JComboBox deviceComboBox;

  /** The cancel button of this dialog. */
  private final JButton cancelButton =
      new JButton(GuiActivator.getResources().getI18NString("service.gui.CANCEL"));

  /**
   * The video <code>CaptureDeviceInfo</code> this instance started to create the preview of.
   *
   * <p>Because the creation of the preview is asynchronous, it's possible to request the preview of
   * one and the same device multiple times. Which may lead to failures because of, for example,
   * busy devices and/or resources (as is the case with LTI-CIVIL and video4linux2).
   */
  private static MediaDevice videoDeviceInPreview;

  /** The selected media device. */
  private MediaDevice selectedDevice;

  /**
   * Creates an instance of <tt>SelectScreenDialog</tt> by specifying the list of possible desktop
   * devices to choose from.
   *
   * @param desktopDevices the list of possible desktop devices to choose from
   */
  public SelectScreenDialog(List<MediaDevice> desktopDevices) {
    setModal(true);

    setPreferredSize(new Dimension(400, 300));

    Container contentPane = getContentPane();
    contentPane.setLayout(new BorderLayout());

    deviceComboBox = new JComboBox(desktopDevices.toArray());
    contentPane.add(deviceComboBox, BorderLayout.NORTH);

    deviceComboBox.setRenderer(new ComboRenderer());

    contentPane.add(createPreview(deviceComboBox));

    contentPane.add(createButtonsPanel(), BorderLayout.SOUTH);
  }

  /**
   * Returns the selected device.
   *
   * @return the selected device
   */
  public MediaDevice getSelectedDevice() {
    return selectedDevice;
  }

  /**
   * Creates the buttons panel.
   *
   * @return the buttons panel
   */
  private Component createButtonsPanel() {
    JPanel buttonsPanel = new TransparentPanel(new FlowLayout(FlowLayout.RIGHT));

    JButton okButton = new JButton(GuiActivator.getResources().getI18NString("service.gui.OK"));

    okButton.addActionListener(
        new ActionListener() {
          public void actionPerformed(ActionEvent e) {
            selectedDevice = (MediaDevice) deviceComboBox.getSelectedItem();

            dispose();
          }
        });

    buttonsPanel.add(okButton);

    cancelButton.addActionListener(
        new ActionListener() {
          public void actionPerformed(ActionEvent e) {
            selectedDevice = null;
            dispose();
          }
        });

    buttonsPanel.add(cancelButton);

    return buttonsPanel;
  }

  /**
   * Create preview component.
   *
   * @param comboBox the options.
   * @return the component.
   */
  private static Component createPreview(final JComboBox comboBox) {
    final JComponent preview;

    JLabel noPreview =
        new JLabel(GuiActivator.getResources().getI18NString("impl.media.configform.NO_PREVIEW"));
    noPreview.setHorizontalAlignment(SwingConstants.CENTER);
    noPreview.setVerticalAlignment(SwingConstants.CENTER);

    preview = createVideoContainer(noPreview);

    preview.setPreferredSize(new Dimension(WIDTH, 280));
    preview.setMaximumSize(new Dimension(WIDTH, 280));

    final ActionListener comboBoxListener =
        new ActionListener() {
          public void actionPerformed(ActionEvent event) {
            MediaDevice device = (MediaDevice) comboBox.getSelectedItem();

            if ((device != null) && device.equals(videoDeviceInPreview)) return;

            Exception exception;
            try {
              createPreview(device, preview);
              exception = null;
            } catch (IOException ex) {
              exception = ex;
            } catch (MediaException ex) {
              exception = ex;
            }
            if (exception != null) {
              logger.error("Failed to create preview for device " + device, exception);

              device = null;
            }

            videoDeviceInPreview = device;
          }
        };
    comboBox.addActionListener(comboBoxListener);

    /*
     * We have to initialize the controls to reflect the configuration
     * at the time of creating this instance. Additionally, because the
     * video preview will stop when it and its associated controls
     * become unnecessary, we have to restart it when the mentioned
     * controls become necessary again. We'll address the two goals
     * described by pretending there's a selection in the video combo
     * box when the combo box in question becomes displayable.
     */
    comboBox.addHierarchyListener(
        new HierarchyListener() {
          public void hierarchyChanged(HierarchyEvent event) {
            if (((event.getChangeFlags() & HierarchyEvent.DISPLAYABILITY_CHANGED) != 0)
                && comboBox.isDisplayable()) {
              // let current changes end their execution
              // and after that trigger action on combobox
              SwingUtilities.invokeLater(
                  new Runnable() {
                    public void run() {
                      comboBoxListener.actionPerformed(null);
                    }
                  });
            } else {
              if (!comboBox.isDisplayable()) videoDeviceInPreview = null;
            }
          }
        });

    return preview;
  }

  /**
   * Creates preview for the device(video) in the video container.
   *
   * @param device the device
   * @param videoContainer the container
   * @throws IOException a problem accessing the device.
   * @throws MediaException a problem getting preview.
   */
  private static void createPreview(MediaDevice device, final JComponent videoContainer)
      throws IOException, MediaException {
    videoContainer.removeAll();

    videoContainer.revalidate();
    videoContainer.repaint();

    if (device == null) return;

    Component c =
        (Component)
            GuiActivator.getMediaService()
                .getVideoPreviewComponent(
                    device, videoContainer.getSize().width, videoContainer.getSize().height);

    videoContainer.add(c);
  }

  /**
   * Creates the video container.
   *
   * @param noVideoComponent the container component.
   * @return the video container.
   */
  private static JComponent createVideoContainer(Component noVideoComponent) {
    return new VideoContainer(noVideoComponent, false);
  }

  /** Custom combo box renderer. */
  private static class ComboRenderer extends DefaultListCellRenderer {
    @Override
    public Component getListCellRendererComponent(
        JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
      super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus);

      MediaDevice mediaDevice = (MediaDevice) value;

      Dimension screenSize = null;
      if (mediaDevice != null) screenSize = ((VideoMediaFormat) mediaDevice.getFormat()).getSize();

      this.setText(screenSize.width + "x" + screenSize.height);

      return this;
    }
  }

  /**
   * Automatically press the cancel button when this dialog has been escaped.
   *
   * @param escaped indicates if this dialog has been closed by pressing the ESC key
   */
  @Override
  protected void close(boolean escaped) {
    if (escaped) cancelButton.doClick();
  }
}
  /**
   * Create preview component.
   *
   * @param comboBox the options.
   * @return the component.
   */
  private static Component createPreview(final JComboBox comboBox) {
    final JComponent preview;

    JLabel noPreview =
        new JLabel(GuiActivator.getResources().getI18NString("impl.media.configform.NO_PREVIEW"));
    noPreview.setHorizontalAlignment(SwingConstants.CENTER);
    noPreview.setVerticalAlignment(SwingConstants.CENTER);

    preview = createVideoContainer(noPreview);

    preview.setPreferredSize(new Dimension(WIDTH, 280));
    preview.setMaximumSize(new Dimension(WIDTH, 280));

    final ActionListener comboBoxListener =
        new ActionListener() {
          public void actionPerformed(ActionEvent event) {
            MediaDevice device = (MediaDevice) comboBox.getSelectedItem();

            if ((device != null) && device.equals(videoDeviceInPreview)) return;

            Exception exception;
            try {
              createPreview(device, preview);
              exception = null;
            } catch (IOException ex) {
              exception = ex;
            } catch (MediaException ex) {
              exception = ex;
            }
            if (exception != null) {
              logger.error("Failed to create preview for device " + device, exception);

              device = null;
            }

            videoDeviceInPreview = device;
          }
        };
    comboBox.addActionListener(comboBoxListener);

    /*
     * We have to initialize the controls to reflect the configuration
     * at the time of creating this instance. Additionally, because the
     * video preview will stop when it and its associated controls
     * become unnecessary, we have to restart it when the mentioned
     * controls become necessary again. We'll address the two goals
     * described by pretending there's a selection in the video combo
     * box when the combo box in question becomes displayable.
     */
    comboBox.addHierarchyListener(
        new HierarchyListener() {
          public void hierarchyChanged(HierarchyEvent event) {
            if (((event.getChangeFlags() & HierarchyEvent.DISPLAYABILITY_CHANGED) != 0)
                && comboBox.isDisplayable()) {
              // let current changes end their execution
              // and after that trigger action on combobox
              SwingUtilities.invokeLater(
                  new Runnable() {
                    public void run() {
                      comboBoxListener.actionPerformed(null);
                    }
                  });
            } else {
              if (!comboBox.isDisplayable()) videoDeviceInPreview = null;
            }
          }
        });

    return preview;
  }