/*
 * Licensed Materials - Property of Perforce Software, Inc. 
 * © Copyright Perforce Software, Inc. 2014, 2021 
 * © Copyright IBM Corp. 2009, 2014
 * © Copyright ILOG 1996, 2009
 * All Rights Reserved.
 *
 * Note to U.S. Government Users Restricted Rights:
 * The Software and Documentation were developed at private expense and
 * are "Commercial Items" as that term is defined at 48 CFR 2.101,
 * consisting of "Commercial Computer Software" and
 * "Commercial Computer Software Documentation", as such terms are
 * used in 48 CFR 12.212 or 48 CFR 227.7202-1 through 227.7202-4,
 * as applicable.
 */

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.ComponentOrientation;
import java.awt.FlowLayout;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.SystemColor;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.MessageFormat;
import java.util.Locale;

import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JRootPane;
import javax.swing.JTextField;

import ilog.views.diagrammer.IlvDiagrammer;
import ilog.views.diagrammer.application.IlvDiagrammerViewBar;
import ilog.views.graphlayout.GraphLayoutEvent;
import ilog.views.graphlayout.GraphLayoutEventListener;
import ilog.views.graphlayout.IlvGraphLayout;
import ilog.views.graphlayout.IlvGraphLayoutReport;
import ilog.views.graphlayout.random.IlvRandomLayout;
import ilog.views.sdm.renderer.graphlayout.IlvGraphLayoutRenderer;
import ilog.views.sdm.util.IlvSDMMutableStyleSheet;
import ilog.views.util.IlvLocaleUtil;
import ilog.views.util.IlvProductUtil;
import ilog.views.util.IlvResourceUtil;
import ilog.views.util.swing.IlvSwingUtil;

/**
 * This is a very simple application that uses the
 * <code>IlvDiagrammer</code> to perform a tree layout. It loads a style sheet
 * containing the tree layout specification. It allows to set various tree
 * layout parameters by using the <code>IlvSDMMutableStyleSheet</code>.
 */
public class TreeLayoutApp extends JRootPane {
  
  {
    // This sample uses JViews Diagrammer features. When deploying an
    // application that includes this code, you need to be in possession
    // of a Perforce JViews Diagrammer Deployment license.
    IlvProductUtil.DeploymentLicenseRequired(IlvProductUtil.JViews_Diagrammer_Deployment);
  }

  /** The diagrammer */
  IlvDiagrammer diagrammer = new IlvDiagrammer();

  /** A graph layout event listener */
  LayoutIterationListener layoutListener = new LayoutIterationListener();

  /** A text field to display messages */
  JTextField msgLine = new JTextField();

  /** The style sheet for temporary changes */
  IlvSDMMutableStyleSheet styleSheet = new IlvSDMMutableStyleSheet(diagrammer.getEngine(), true, false);

  /** The flow direction selector */
  JComboBox<String> flowDirectionSelector = new JComboBox<String>();

  /** The link style selector */
  JComboBox<String> linkStyleSelector = new JComboBox<String>();

  /** The layout mode selector */
  JComboBox<String> layoutModeSelector = new JComboBox<String>();

  /** The default offset */
  static final double DEFAULT_OFFSET = 20.;

  /** Text fields for the offset parameters */
  NumberField branchOffsetSelector = new NumberField(0, 200, DEFAULT_OFFSET, true, 6, 5);
  NumberField siblingOffsetSelector = new NumberField(0, 200, DEFAULT_OFFSET, true, 6, 5);
  NumberField parentOffsetSelector = new NumberField(0, 200, DEFAULT_OFFSET, true, 6, 5);
  NumberField startAngleSelector = new NumberField(0, 360, 0, false, 3, 2);
  NumberField rootAngleRangeSelector = new NumberField(1, 360, 360, false, 3, 10);
  NumberField innerAngleRangeSelector = new NumberField(1, 360, 360, false, 3, 10);
  NumberField leafAngleRangeSelector = new NumberField(1, 360, 360, false, 3, 10);

  /** Whether to use automatic layout */
  boolean autoLayout = false;

  /** Whether to do fit to view after layout */
  boolean autoFit = true;

  /** Layout parameter panels. */
  JPanel normalPanel;
  JPanel balloonPanel;

  /**
   * Initializes the application.
   */
  public void init() {
    // we use the standard diagrammer toolbar
    IlvDiagrammerViewBar toolbar = new IlvDiagrammerViewBar();

    // various settings of the diagrammer
    diagrammer.setSelectMode(true);
    diagrammer.setScrollable(true);
    diagrammer.setEditingAllowed(true);
    diagrammer.setMinimumZoom(0.02);
    diagrammer.setMaximumZoom(10);
    diagrammer.getView().setBackground(Color.white);
    diagrammer.getView().setForeground(SystemColor.windowText);

    // create the file selector
    JComboBox<String> fileSelector = new JComboBox<String>();
    fileSelector.addItem("small");
    fileSelector.addItem("medium");
    fileSelector.addItem("large");
    fileSelector.addItem("balloonSmall");
    fileSelector.addItem("balloonMedium");
    fileSelector.addItem("balloonLarge");
    fileSelector.setToolTipText(getString("FileSelector.Tooltip"));
    fileSelector.addActionListener(new ActionListener() {
      Override
      public void actionPerformed(ActionEvent event) {
        SuppressWarnings("unchecked")
        JComboBox<String> comboBox = (JComboBox<String>) event.getSource();
        String fileName = (String) comboBox.getSelectedItem();
        loadDataFile(fileName);
      }
    });

    // create the randomize button
    JButton randomizeButton = new JButton(getString("RandomLayout.Button.Label"));
    randomizeButton.setToolTipText(getString("RandomLayout.Button.Tooltip"));
    randomizeButton.addActionListener(new ActionListener() {
      Override
      public void actionPerformed(ActionEvent evt) {
        randomize();
      }
    });

    // create the layout button
    JButton layoutButton = new JButton(getString("TreeLayout.Button.Label"));
    layoutButton.setToolTipText(getString("TreeLayout.Button.Tooltip"));
    layoutButton.addActionListener(new ActionListener() {
      Override
      public void actionPerformed(ActionEvent evt) {
        // before performing layout, make sure that the values in the text
        // fields are transfered to the style sheet
        styleSheet.setAdjusting(true);
        try {
          setOffsetOrAngle("branchOffset", branchOffsetSelector);
          setOffsetOrAngle("siblingOffset", siblingOffsetSelector);
          setOffsetOrAngle("parentChildOffset", parentOffsetSelector);
          setOffsetOrAngle("balloonStartAngle", startAngleSelector);
          setOffsetOrAngle("balloonRootChildrenAngle", rootAngleRangeSelector);
          setOffsetOrAngle("balloonInnerChildrenAngle", innerAngleRangeSelector);
          setOffsetOrAngle("balloonLeafChildrenAngle", leafAngleRangeSelector);
        } finally {
          styleSheet.setAdjusting(false);
        }
        performLayout();
      }
    });

    JCheckBox fitToViewBox = new JCheckBox(getString("AutoFit.CheckBox.Label"), autoFit);
    fitToViewBox.setToolTipText(getString("AutoFit.CheckBox.Tooltip"));
    fitToViewBox.addActionListener(new ActionListener() {
      Override
      public void actionPerformed(ActionEvent evt) {
        autoFit = ((JCheckBox) evt.getSource()).isSelected();
      }
    });

    JCheckBox autoLayoutBox = new JCheckBox(getString("AutoLayout.CheckBox.Label"), autoLayout);
    autoLayoutBox.setToolTipText(getString("AutoLayout.CheckBox.Tooltip"));
    autoLayoutBox.addActionListener(new ActionListener() {
      Override
      public void actionPerformed(ActionEvent evt) {
        autoLayout = ((JCheckBox) evt.getSource()).isSelected();
      }
    });

    // create the panel for the layout buttons
    JPanel layoutButtonPanel = new JPanel();
    layoutButtonPanel.setLayout(new FlowLayout());
    layoutButtonPanel.add(new JLabel("   "));
    layoutButtonPanel.add(autoLayoutBox);
    layoutButtonPanel.add(randomizeButton);
    layoutButtonPanel.add(layoutButton);
    layoutButtonPanel.add(fitToViewBox);

    // create the top panel with the toolbar and the file selector
    JPanel topPanel = new JPanel();
    topPanel.setLayout(new FlowLayout(FlowLayout.LEADING));
    topPanel.add(toolbar);
    JLabel label = new JLabel(getString("FileSelector.Label"));
    label.setToolTipText(getString("FileSelector.Tooltip"));
    topPanel.add(label);
    topPanel.add(fileSelector);

    // create the layout parameter panels
    normalPanel = createNormalParameterPanel();
    balloonPanel = createBalloonParameterPanel();

    // create the bottom panel with the layout buttons and the message line
    JPanel bottomPanel = new JPanel();
    bottomPanel.setLayout(new BorderLayout());
    bottomPanel.add(layoutButtonPanel, BorderLayout.NORTH);
    bottomPanel.add(normalPanel, BorderLayout.CENTER);
    bottomPanel.add(msgLine, BorderLayout.SOUTH);
    msgLine.setEditable(false);

    // put diagrammer, top panel and bottom panel together
    getContentPane().setLayout(new BorderLayout(0, 0));
    getContentPane().add(diagrammer, BorderLayout.CENTER);
    getContentPane().add(topPanel, BorderLayout.NORTH);
    getContentPane().add(bottomPanel, BorderLayout.SOUTH);

    // set the component orientation according to the locale
    Locale loc = IlvSwingUtil.getDefaultLocale();
    ComponentOrientation co = ComponentOrientation.getOrientation(loc);
    getContentPane().applyComponentOrientation(co);

    try {
      // load the main style file
      diagrammer.setStyleSheet(IlvSwingUtil.getRelativeURL(this, "data/tree.css"));
      // load a mutable style file that we use for temporary style changes
      diagrammer.getEngine().setStyleSheets(1, styleSheet.toString());
    } catch (Exception e) {
      showMessage(e.getMessage());
    }

    // load the initial sample grapher
    loadDataFile("small");

    // add the layout listener to the current graph layout. This must be done
    // here after reading the style file, because before reading the style file,
    // the layout instance is not yet instantiated.
    getGraphLayout().addGraphLayoutEventListener(layoutListener);
  }

  /**
   * Creates the layout parameter panel for balloon mode.
   */
  private JPanel createBalloonParameterPanel() {
    JPanel panel = new JPanel();
    GridBagLayout gridbag = new GridBagLayout();
    GridBagConstraints c = new GridBagConstraints();
    c.fill = GridBagConstraints.HORIZONTAL;
    c.anchor = GridBagConstraints.EAST;
    panel.setLayout(gridbag);

    // layout mode parameter
    c.gridx = 0;
    c.gridy = 0;
    JLabel label = new JLabel(getString("LayoutMode.Label"));
    label.setToolTipText(getString("LayoutMode.Tooltip"));
    panel.add(label, c);

    // angle spacing parameter
    c.gridx = 0;
    c.gridy = 1;
    label = new JLabel(getString("AngleSpacing.Label"));
    label.setToolTipText(getString("AngleSpacing.Tooltip"));
    panel.add(label, c);
    c.gridx = 1;
    JComboBox<String> balloonAngleSpacingSelector = new JComboBox<String>();
    panel.add(balloonAngleSpacingSelector, c);
    balloonAngleSpacingSelector.addItem(getString("AngleSpacing.RegularMode"));
    balloonAngleSpacingSelector.addItem(getString("AngleSpacing.FastPropMode"));
    balloonAngleSpacingSelector.addItem(getString("AngleSpacing.SlowPropMode"));
    balloonAngleSpacingSelector.setSelectedIndex(2);
    balloonAngleSpacingSelector.setToolTipText(getString("AngleSpacing.Tooltip"));
    balloonAngleSpacingSelector.addActionListener(new ActionListener() {
      Override
      public void actionPerformed(ActionEvent event) {
        SuppressWarnings("unchecked")
        JComboBox<String> comboBox = (JComboBox<String>) event.getSource();
        String mode = (String) comboBox.getSelectedItem();
        setBalloonAngleSpacing(mode);
      }
    });

    // radius mode parameter
    c.gridx = 0;
    c.gridy = 2;
    label = new JLabel(getString("RadiusMode.Label"));
    label.setToolTipText(getString("RadiusMode.Tooltip"));
    panel.add(label, c);
    c.gridx = 1;
    JComboBox<String> balloonRadiusModeSelector = new JComboBox<String>();
    panel.add(balloonRadiusModeSelector, c);
    balloonRadiusModeSelector.addItem(getString("RadiusMode.VarMode"));
    balloonRadiusModeSelector.addItem(getString("RadiusMode.OptVarMode"));
    balloonRadiusModeSelector.addItem(getString("RadiusMode.UniLfMode"));
    balloonRadiusModeSelector.addItem(getString("RadiusMode.OptUniLfMode"));
    balloonRadiusModeSelector.addItem(getString("RadiusMode.UniMode"));
    balloonRadiusModeSelector.setSelectedIndex(3);
    balloonRadiusModeSelector.setToolTipText(getString("RadiusMode.Tooltip"));
    balloonRadiusModeSelector.addActionListener(new ActionListener() {
      Override
      public void actionPerformed(ActionEvent event) {
        SuppressWarnings("unchecked")
        JComboBox<String> comboBox = (JComboBox<String>) event.getSource();
        String mode = (String) comboBox.getSelectedItem();
        setBalloonRadiusMode(mode);
      }
    });

    // branch offset = node offset
    c.gridx = 0;
    c.gridy = 3;
    c.insets = new Insets(5, 0, 0, 0);
    label = new JLabel(getString("NodeOffset.Label"));
    label.setToolTipText(getString("SiblingOffset.Tooltip"));
    panel.add(label, c);

    // branch offset = node offset
    c.gridx = 2;
    c.gridy = 0;
    c.insets = new Insets(0, 25, 0, 0);
    label = new JLabel(getString("StartAngle.Label"));
    label.setToolTipText(getString("StartAngle.Tooltip"));
    panel.add(label, c);

    c.gridy = 1;
    label = new JLabel(getString("RootAngleRange.Label"));
    label.setToolTipText(getString("RootAngleRange.Tooltip"));
    panel.add(label, c);

    c.gridy = 2;
    label = new JLabel(getString("InnerAngleRange.Label"));
    label.setToolTipText(getString("InnerAngleRange.Tooltip"));
    panel.add(label, c);

    c.gridy = 3;
    label = new JLabel(getString("LeafAngleRange.Label"));
    label.setToolTipText(getString("LeafAngleRange.Tooltip"));
    panel.add(label, c);

    c.gridx = 3;
    c.gridy = 0;
    panel.add(startAngleSelector, c);
    c.gridy = 1;
    panel.add(rootAngleRangeSelector, c);
    c.gridy = 2;
    panel.add(innerAngleRangeSelector, c);
    c.gridy = 3;
    panel.add(leafAngleRangeSelector, c);

    startAngleSelector.setToolTipText(getString("StartAngle.Tooltip"));
    startAngleSelector.addActionListener(new ActionListener() {
      Override
      public void actionPerformed(ActionEvent e) {
        setOffsetOrAngle("balloonStartAngle", (NumberField) e.getSource());
      }
    });

    rootAngleRangeSelector.setToolTipText(getString("RootAngleRange.Tooltip"));
    rootAngleRangeSelector.addActionListener(new ActionListener() {
      Override
      public void actionPerformed(ActionEvent e) {
        setOffsetOrAngle("balloonRootChildrenAngle", (NumberField) e.getSource());
      }
    });

    innerAngleRangeSelector.setToolTipText(getString("InnerAngleRange.Tooltip"));
    innerAngleRangeSelector.addActionListener(new ActionListener() {
      Override
      public void actionPerformed(ActionEvent e) {
        setOffsetOrAngle("balloonInnerChildrenAngle", (NumberField) e.getSource());
      }
    });

    leafAngleRangeSelector.setToolTipText(getString("LeafAngleRange.Tooltip"));
    leafAngleRangeSelector.addActionListener(new ActionListener() {
      Override
      public void actionPerformed(ActionEvent e) {
        setOffsetOrAngle("balloonLeafChildrenAngle", (NumberField) e.getSource());
      }
    });

    // set the component orientation according to the locale
    Locale loc = IlvSwingUtil.getDefaultLocale();
    ComponentOrientation co = ComponentOrientation.getOrientation(loc);
    panel.applyComponentOrientation(co);

    return panel;
  }

  /**
   * Creates the layout parameter panel for normal mode.
   */
  private JPanel createNormalParameterPanel() {
    JPanel panel = new JPanel();
    GridBagLayout gridbag = new GridBagLayout();
    GridBagConstraints c = new GridBagConstraints();
    c.fill = GridBagConstraints.HORIZONTAL;
    c.anchor = GridBagConstraints.EAST;
    panel.setLayout(gridbag);

    // layout mode parameter
    c.gridx = 0;
    c.gridy = 0;
    JLabel label = new JLabel(getString("LayoutMode.Label"));
    label.setToolTipText(getString("LayoutMode.Tooltip"));
    panel.add(label, c);
    c.gridx = 1;
    layoutModeSelector = new JComboBox<String>();
    panel.add(layoutModeSelector, c);
    layoutModeSelector.addItem(getString("LayoutMode.FreeMode"));
    layoutModeSelector.addItem(getString("LayoutMode.LevelMode"));
    layoutModeSelector.addItem(getString("LayoutMode.TipOverMode"));
    layoutModeSelector.addItem(getString("LayoutMode.BalloonMode"));
    layoutModeSelector.addItem(getString("LayoutMode.RadialMode"));
    layoutModeSelector.addItem(getString("LayoutMode.AltRadialMode"));
    layoutModeSelector.setSelectedIndex(0);
    layoutModeSelector.setToolTipText(getString("LayoutMode.Tooltip"));
    layoutModeSelector.addActionListener(new ActionListener() {
      Override
      public void actionPerformed(ActionEvent event) {
        SuppressWarnings("unchecked")
        JComboBox<String> comboBox = (JComboBox<String>) event.getSource();
        String mode = (String) comboBox.getSelectedItem();
        setLayoutMode(mode);
      }
    });

    // flow direction parameter
    c.gridx = 0;
    c.gridy = 1;
    label = new JLabel(getString("FlowDirection.Label"));
    label.setToolTipText(getString("FlowDirection.Tooltip"));
    panel.add(label, c);
    c.gridx = 1;
    panel.add(flowDirectionSelector, c);
    flowDirectionSelector.addItem(getString("FlowDirection.Top"));
    flowDirectionSelector.addItem(getString("FlowDirection.Bottom"));
    flowDirectionSelector.addItem(getString("FlowDirection.Left"));
    flowDirectionSelector.addItem(getString("FlowDirection.Right"));
    flowDirectionSelector.setSelectedIndex(1);
    flowDirectionSelector.setToolTipText(getString("FlowDirection.Tooltip"));
    flowDirectionSelector.addActionListener(new ActionListener() {
      Override
      public void actionPerformed(ActionEvent event) {
        SuppressWarnings("unchecked")
        JComboBox<String> comboBox = (JComboBox<String>) event.getSource();
        String flow = (String) comboBox.getSelectedItem();
        setFlowDirection(flow);
      }
    });

    // link style parameter
    c.gridx = 0;
    c.gridy = 2;
    label = new JLabel(getString("LinkStyle.Label"));
    label.setToolTipText(getString("LinkStyle.Tooltip"));
    panel.add(label, c);
    c.gridx = 1;
    panel.add(linkStyleSelector, c);
    linkStyleSelector.addItem(getString("LinkStyle.Orthogonal"));
    linkStyleSelector.addItem(getString("LinkStyle.Straight"));
    linkStyleSelector.addItem(getString("LinkStyle.Mixed"));
    linkStyleSelector.setSelectedIndex(0);
    linkStyleSelector.setToolTipText(getString("LinkStyle.Tooltip"));
    linkStyleSelector.addActionListener(new ActionListener() {
      Override
      public void actionPerformed(ActionEvent event) {
        SuppressWarnings("unchecked")
        JComboBox<String> comboBox = (JComboBox<String>) event.getSource();
        String style = (String) comboBox.getSelectedItem();
        setGlobalLinkStyle(style);
      }
    });

    // alignment parameter
    c.gridx = 0;
    c.gridy = 3;
    label = new JLabel(getString("Alignment.Label"));
    label.setToolTipText(getString("Alignment.Tooltip"));
    panel.add(label, c);
    c.gridx = 1;
    JComboBox<String> alignmentSelector = new JComboBox<String>();
    panel.add(alignmentSelector, c);
    alignmentSelector.addItem(getString("Alignment.Center"));
    alignmentSelector.addItem(getString("Alignment.East"));
    alignmentSelector.addItem(getString("Alignment.West"));
    alignmentSelector.addItem(getString("Alignment.TipOver"));
    alignmentSelector.setSelectedIndex(0);
    alignmentSelector.setToolTipText(getString("Alignment.Tooltip"));
    alignmentSelector.addActionListener(new ActionListener() {
      Override
      public void actionPerformed(ActionEvent event) {
        SuppressWarnings("unchecked")
        JComboBox<String> comboBox = (JComboBox<String>) event.getSource();
        String alignment = (String) comboBox.getSelectedItem();
        setGlobalAlignment(alignment);
      }
    });

    // tree layout offset parameters
    c.gridx = 3;
    c.gridy = 1;
    panel.add(siblingOffsetSelector, c);
    c.gridy = 2;
    panel.add(branchOffsetSelector, c);
    c.gridy = 3;
    panel.add(parentOffsetSelector, c);

    c.gridx = 2;
    c.gridy = 0;
    c.insets = new Insets(0, 25, 0, 0);
    label = new JLabel(getString("OffsetIntro.Label"));
    panel.add(label, c);
    c.gridy = 1;
    label = new JLabel(getString("SiblingOffset.Label"));
    label.setToolTipText(getString("BranchOffset.Tooltip"));
    panel.add(label, c);
    c.gridy = 2;
    label = new JLabel(getString("BranchOffset.Label"));
    label.setToolTipText(getString("SiblingOffset.Tooltip"));
    panel.add(label, c);
    c.gridy = 3;
    label = new JLabel(getString("ParentChildOffset.Label"));
    label.setToolTipText(getString("ParentChildOffset.Tooltip"));
    panel.add(label, c);

    branchOffsetSelector.setToolTipText(getString("SiblingOffset.Tooltip"));
    branchOffsetSelector.addActionListener(new ActionListener() {
      Override
      public void actionPerformed(ActionEvent e) {
        setOffsetOrAngle("branchOffset", (NumberField) e.getSource());
      }
    });

    siblingOffsetSelector.setToolTipText(getString("BranchOffset.Tooltip"));
    siblingOffsetSelector.addActionListener(new ActionListener() {
      Override
      public void actionPerformed(ActionEvent e) {
        setOffsetOrAngle("siblingOffset", (NumberField) e.getSource());
      }
    });

    parentOffsetSelector.setToolTipText(getString("ParentChildOffset.Tooltip"));
    parentOffsetSelector.addActionListener(new ActionListener() {
      Override
      public void actionPerformed(ActionEvent e) {
        setOffsetOrAngle("parentChildOffset", (NumberField) e.getSource());
      }
    });

    // set the component orientation according to the locale
    Locale loc = IlvSwingUtil.getDefaultLocale();
    ComponentOrientation co = ComponentOrientation.getOrientation(loc);
    panel.applyComponentOrientation(co);

    return panel;
  }

  /**
   * Install the parameter panel.
   */
  private void installParameterPanel(JPanel panel) {
    if (panel.getParent() != null)
      return;

    GridBagConstraints c = new GridBagConstraints();
    c.fill = GridBagConstraints.HORIZONTAL;
    c.anchor = GridBagConstraints.EAST;

    if (normalPanel.getParent() != null) {
      JPanel parent = (JPanel) normalPanel.getParent();
      parent.remove(normalPanel);
      normalPanel.remove(layoutModeSelector);
      c.gridy = 0;
      c.gridx = 1;
      panel.add(layoutModeSelector, c);
      normalPanel.remove(branchOffsetSelector);
      c.gridy = 3;
      c.gridx = 1;
      c.insets = new Insets(5, 0, 0, 0);
      panel.add(branchOffsetSelector, c);
      parent.add(panel, BorderLayout.CENTER);
      parent.revalidate();
      parent.repaint();
    } else if (balloonPanel.getParent() != null) {
      JPanel parent = (JPanel) balloonPanel.getParent();
      parent.remove(balloonPanel);
      balloonPanel.remove(layoutModeSelector);
      c.gridy = 0;
      c.gridx = 1;
      panel.add(layoutModeSelector, c);
      balloonPanel.remove(branchOffsetSelector);
      c.gridy = 2;
      c.gridx = 3;
      panel.add(branchOffsetSelector, c);
      parent.add(panel, BorderLayout.CENTER);
      parent.revalidate();
      parent.repaint();
    }
  }

  /**
   * Load a sample data file.
   * 
   * @param fileNameBase
   *          The base of the filename, excluding the path prefix and the
   *          extension suffix.
   */
  private void loadDataFile(String fileNameBase) {
    try {
      showMessage(getString("FileReadingStartMessage"), fileNameBase);
      diagrammer.setDataFile(IlvSwingUtil.getRelativeURL(this, "data/" + fileNameBase + ".xml"));
      showMessage(getString("FileReadingDoneMessage"), fileNameBase);
    } catch (Exception e) {
      showMessage(e.getMessage());
    }
  }

  /**
   * Sets the layout mode.
   */
  private void setLayoutMode(String mode) {
    styleSheet.setDeclaration("GraphLayout", "aspectRatio", "1.5");
    if (mode.equals(getString("LayoutMode.FreeMode"))) {
      flowDirectionSelector.setEnabled(true);
      linkStyleSelector.setEnabled(true);
      styleSheet.setDeclaration("GraphLayout", "layoutMode", "FREE");
      installParameterPanel(normalPanel);
    } else if (mode.equals(getString("LayoutMode.LevelMode"))) {
      flowDirectionSelector.setEnabled(true);
      linkStyleSelector.setEnabled(true);
      styleSheet.setDeclaration("GraphLayout", "layoutMode", "LEVEL");
      installParameterPanel(normalPanel);
    } else if (mode.equals(getString("LayoutMode.TipOverMode"))) {
      flowDirectionSelector.setEnabled(true);
      linkStyleSelector.setEnabled(true);
      styleSheet.setDeclaration("GraphLayout", "layoutMode", "TIP_LEAVES_OVER");
      installParameterPanel(normalPanel);
    } else if (mode.equals(getString("LayoutMode.BalloonMode"))) {
      flowDirectionSelector.setEnabled(false);
      linkStyleSelector.setEnabled(false);
      styleSheet.setDeclaration("GraphLayout", "layoutMode", "BALLOON");
      styleSheet.setDeclaration("GraphLayout", "aspectRatio", "1.0");
      installParameterPanel(balloonPanel);
    } else if (mode.equals(getString("LayoutMode.RadialMode"))) {
      flowDirectionSelector.setEnabled(false);
      linkStyleSelector.setEnabled(false);
      styleSheet.setDeclaration("GraphLayout", "layoutMode", "RADIAL");
      installParameterPanel(normalPanel);
    } else if (mode.equals(getString("LayoutMode.AltRadialMode"))) {
      flowDirectionSelector.setEnabled(false);
      linkStyleSelector.setEnabled(false);
      styleSheet.setDeclaration("GraphLayout", "layoutMode", "ALTERNATING_RADIAL");
      installParameterPanel(normalPanel);
    }

    if (autoLayout)
      performLayout();
  }

  /**
   * Sets the flow direction.
   */
  private void setFlowDirection(String flow) {
    if (flow.equals(getString("FlowDirection.Top")))
      styleSheet.setDeclaration("GraphLayout", "flowDirection", "Top");
    else if (flow.equals(getString("FlowDirection.Bottom")))
      styleSheet.setDeclaration("GraphLayout", "flowDirection", "Bottom");
    else if (flow.equals(getString("FlowDirection.Left")))
      styleSheet.setDeclaration("GraphLayout", "flowDirection", "Left");
    else if (flow.equals(getString("FlowDirection.Right")))
      styleSheet.setDeclaration("GraphLayout", "flowDirection", "Right");

    if (autoLayout)
      performLayout();
  }

  /**
   * Sets the global link style.
   */
  private void setGlobalLinkStyle(String style) {
    if (style.equals(getString("LinkStyle.Orthogonal")))
      styleSheet.setDeclaration("GraphLayout", "globalLinkStyle", "ORTHOGONAL_STYLE");
    else if (style.equals(getString("LinkStyle.Straight")))
      styleSheet.setDeclaration("GraphLayout", "globalLinkStyle", "STRAIGHT_LINE_STYLE");
    else if (style.equals(getString("LinkStyle.Mixed")))
      styleSheet.setDeclaration("GraphLayout", "globalLinkStyle", "MIXED_STYLE");

    if (autoLayout)
      performLayout();
  }

  /**
   * Sets the global alignment.
   */
  private void setGlobalAlignment(String alignment) {
    if (alignment.equals(getString("Alignment.Center")))
      styleSheet.setDeclaration("GraphLayout", "globalAlignment", "CENTER");
    else if (alignment.equals(getString("Alignment.East")))
      styleSheet.setDeclaration("GraphLayout", "globalAlignment", "EAST");
    else if (alignment.equals(getString("Alignment.West")))
      styleSheet.setDeclaration("GraphLayout", "globalAlignment", "WEST");
    else if (alignment.equals(getString("Alignment.TipOver")))
      styleSheet.setDeclaration("GraphLayout", "globalAlignment", "TIP_OVER");

    if (autoLayout)
      performLayout();
  }

  /**
   * Sets the angle spacing mode in balloon mode.
   */
  private void setBalloonAngleSpacing(String mode) {
    if (mode.equals(getString("AngleSpacing.RegularMode")))
      styleSheet.setDeclaration("GraphLayout", "balloonAngleSpacing", "REGULAR");
    else if (mode.equals(getString("AngleSpacing.FastPropMode")))
      styleSheet.setDeclaration("GraphLayout", "balloonAngleSpacing", "FAST_PROPORTIONAL");
    else if (mode.equals(getString("AngleSpacing.SlowPropMode")))
      styleSheet.setDeclaration("GraphLayout", "balloonAngleSpacing", "PROPORTIONAL");

    if (autoLayout)
      performLayout();
  }

  /**
   * Sets the radius mode in balloon mode.
   */
  private void setBalloonRadiusMode(String mode) {
    if (mode.equals(getString("RadiusMode.VarMode")))
      styleSheet.setDeclaration("GraphLayout", "balloonRadiusMode", "VARIABLE_RADIUS");
    else if (mode.equals(getString("RadiusMode.OptVarMode")))
      styleSheet.setDeclaration("GraphLayout", "balloonRadiusMode", "OPTIMIZED_VARIABLE_RADIUS");
    else if (mode.equals(getString("RadiusMode.UniLfMode")))
      styleSheet.setDeclaration("GraphLayout", "balloonRadiusMode", "UNIFORM_LEAVES_RADIUS");
    else if (mode.equals(getString("RadiusMode.OptUniLfMode")))
      styleSheet.setDeclaration("GraphLayout", "balloonRadiusMode", "OPTIMIZED_UNIFORM_LEAVES_RADIUS");
    else if (mode.equals(getString("RadiusMode.UniMode")))
      styleSheet.setDeclaration("GraphLayout", "balloonRadiusMode", "UNIFORM_RADIUS");

    if (autoLayout)
      performLayout();
  }

  /**
   * Sets the sibling, branch or parent/child offset from a textfield.
   */
  private void setOffsetOrAngle(String property, NumberField valueSelector) {
    try {
      // get the value of the parameter from the valueSelector
      double value = valueSelector.getValue();

      // set the new value of the layout property
      if (property.contains("Angle"))
        styleSheet.setDeclaration("GraphLayout", property, "" + (int) value);
      else
        styleSheet.setDeclaration("GraphLayout", property, "" + value);
    } catch (Exception ex) {
      showMessage(getString("IllegalPropertyMessage"), property, ex.getMessage());
    }

    if (autoLayout)
      performLayout();
  }

  /**
   * Performs the tree layout. The layout type is stored in the CSS file,
   * therefore we don't need to set the tree layout explicitely. After loading
   * the graph and the CSS style sheet, the tree layout is already instantiated.
   */
  private void performLayout() {
    showMessage(getString("LayoutStartMessage"));

    // initialize the iteration listener
    layoutListener.initialize(getGraphLayout());

    // Perform Tree Layout as node layout. Tree layout always handles nodes
    // and links at the same time, therefore a separate link layout is not
    // necessary.
    if (diagrammer.isNodeLayoutAvailable()) {
      // perform the layout
      diagrammer.layoutAllNodes();
      // show the layout report information about the return code
      IlvGraphLayoutReport report = getGraphLayout().getLayoutReport();
      if (report != null) {
        // showMessage(getString("LayoutDoneMessage"),
        // report.codeToString(report.getCode()));
        showMessage("");
        // if layout was successfully done, fit in the diagrammer's view
        if (report.getCode() == IlvGraphLayoutReport.LAYOUT_DONE) {
          if (autoFit)
            diagrammer.fitToContents();
        }
      }
    }
  }

  /**
   * Randomize the node positions.
   */
  private void randomize() {
    // clear previous message
    showMessage("");

    // create a new random layout
    IlvRandomLayout randomLayout = new IlvRandomLayout();

    // save the old layout instance
    IlvGraphLayout oldLayout = getGraphLayout();

    // tell the diagrammer to temporarily use the random layout, which
    // disabled the tree layout.
    setGraphLayout(randomLayout);

    if (diagrammer.isNodeLayoutAvailable()) {
      // perform the layout
      diagrammer.layoutAllNodes();
    }

    // restore the old layout instance
    setGraphLayout(oldLayout);
  }

  /**
   * Returns the graph layout currently used by the diagrammer.
   */
  private IlvGraphLayout getGraphLayout() {
    IlvGraphLayoutRenderer renderer = (IlvGraphLayoutRenderer) diagrammer.getEngine().getNodeLayoutRenderer();
    return renderer == null ? null : renderer.getGraphLayout();
  }

  /**
   * Sets the graph layout currently used by the diagrammer.
   */
  private void setGraphLayout(IlvGraphLayout layout) {
    IlvGraphLayoutRenderer renderer = (IlvGraphLayoutRenderer) diagrammer.getEngine().getNodeLayoutRenderer();
    if (renderer == null)
      return;
    renderer.setGraphLayout(layout);
  }

  /**
   * Displays a message.
   */
  void showMessage(String message) {
    // the message is displayed in the message line
    msgLine.setText(message);
    msgLine.paintImmediately(0, 0, msgLine.getWidth(), msgLine.getHeight());
  }

  void showMessage(String msgformat, Object... val) {
    showMessage(MessageFormat.format(msgformat, val));
  }

  /**
   * Returns a string.
   */
  static String getString(String key) {
    return IlvResourceUtil.getString(key, TreeLayoutApp.class, IlvLocaleUtil.getCurrentLocale());
  }

  /**
   * Allows you to run the demo as a standalone application.
   */
  public static void main(String[] args) {
    javax.swing.SwingUtilities.invokeLater(new Runnable() {
      Override
      public void run() {
        TreeLayoutApp app = new TreeLayoutApp();
        app.init();

        JFrame frame = new JFrame(getString("Frame.Label"));
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(600, 600);
        frame.getContentPane().add(app);
        frame.setVisible(true);

      }
    });
  }

  // --------------------------------------------------------------------------

  /**
   * A graph layout iteration listener. Implementing the interface
   * GraphLayoutEventListener gives you the possibility to receive during the
   * layout information about the behavior of the layout algorithm. This
   * information is contained in the graph layout event.
   * 
   * In our case, we will simply print the percentage completed by the layout
   * each time the method layoutStepPerformed is called, that is after each
   * iteration of the Tree Layout algorithm.
   */
  class LayoutIterationListener implements GraphLayoutEventListener {
    IlvGraphLayout layout;
    private float oldPercentage;

    /**
     * This method is automatically called by the layout algorithm.
     */
    Override
    public void layoutStepPerformed(GraphLayoutEvent event) {
      float percentage = event.getLayoutReport().getPercentageComplete();
      if (percentage != oldPercentage) {
        showMessage(getString("PercentageCompleteMessage"), percentage);
        oldPercentage = percentage;
      }
    }

    /**
     * Initialize the listener. This method must be called before the layout is
     * started.
     */
    void initialize(IlvGraphLayout l) {
      if (layout != l) {
        if (layout != null)
          layout.removeGraphLayoutEventListener(this);
        layout = l;
        if (layout != null)
          layout.addGraphLayoutEventListener(this);
      }
      oldPercentage = -1.0f;
    }
  }
}