public EquationLogItemPanel(EquationLogItem equationLogItem) {
      myEquationLogItem = equationLogItem;

      setLayout(new GridBagLayout());
      setBackground(Color.WHITE);

      GridBagConstraints constraints = new GridBagConstraints();
      constraints.gridy = 0;
      constraints.weighty = 0;
      constraints.weightx = 0;
      constraints.fill = GridBagConstraints.NONE;
      constraints.anchor = GridBagConstraints.NORTHWEST;

      JLabel label = new JLabel("equation");
      add(label, constraints);

      constraints.gridx = 1;
      SNodeTree leftTree = new SNodeTree(myEquationLogItem.getLeftRepresentator());
      add(leftTree, constraints);

      constraints.gridx = 2;
      SNodeTree rightTree = new SNodeTree(myEquationLogItem.getRightRepresentator());
      add(rightTree, constraints);

      constraints.gridx = 3;
      constraints.weightx = 1;
      JLabel reasonLabel = new JLabel(myEquationLogItem.getReason());
      reasonLabel.addMouseListener(
          new MouseAdapter() {
            @Override
            public void mousePressed(MouseEvent e) {
              if (e.getClickCount() == 2) {
                String ruleModel = myEquationLogItem.getRuleModel();
                final String ruleID = myEquationLogItem.getRuleId();
                openRule(ruleModel, ruleID);
              }
            }
          });
      add(reasonLabel, constraints);

      List<Pair<String, String>> causes = myEquationLogItem.getCauses();
      if (!causes.isEmpty()) {
        constraints.gridx = 4;
        constraints.weightx = 0;
        CausesTree causesTree = new CausesTree(causes);
        add(causesTree, constraints);
        causesTree.rebuildNow();
      }

      leftTree.rebuildNow();
      rightTree.rebuildNow();
    }
  private void addEquationLog(
      JPanel panel, GridBagConstraints constraints, final EquationLogItem item) {
    constraints.weightx = 0;
    constraints.fill = GridBagConstraints.NONE;
    constraints.anchor = GridBagConstraints.NORTHWEST;

    constraints.gridx = 0;
    JLabel label = new JLabel("equation");
    panel.add(label, constraints);

    constraints.gridx = 1;
    SNodeTree leftTree = new SNodeTree(item.getLeftRepresentator());
    panel.add(leftTree, constraints);

    constraints.gridx = 2;
    SNodeTree rightTree = new SNodeTree(item.getRightRepresentator());
    panel.add(rightTree, constraints);

    constraints.gridx = 3;
    constraints.weightx = 1;
    JLabel reasonLabel = new JLabel(item.getReason());
    reasonLabel.addMouseListener(
        new MouseAdapter() {
          @Override
          public void mousePressed(MouseEvent e) {
            if (e.getClickCount() == 2) {
              String ruleModel = item.getRuleModel();
              final String ruleID = item.getRuleId();
              openRule(ruleModel, ruleID);
            }
          }
        });
    panel.add(reasonLabel, constraints);

    List<Pair<String, String>> causes = item.getCauses();
    constraints.gridx = 4;
    constraints.weightx = 0;
    if (!causes.isEmpty()) {

      CausesTree causesTree = new CausesTree(causes);
      panel.add(causesTree, constraints);
      causesTree.rebuildNow();
    } else {
      add(new JLabel(""), constraints);
    }

    leftTree.rebuildNow();
    rightTree.rebuildNow();
  }
  private void rebuild() {
    removeAll();
    setLayout(new GridBagLayout());

    GridBagConstraints gridBagConstraints = new GridBagConstraints();
    gridBagConstraints.gridx = 0;
    gridBagConstraints.gridy = 0;
    gridBagConstraints.weightx = 1;
    gridBagConstraints.weighty = 0;
    gridBagConstraints.anchor = GridBagConstraints.NORTH;
    gridBagConstraints.fill = GridBagConstraints.BOTH;

    // upper panel
    JButton debugCurrentRootButton =
        new JButton(
            new AbstractAction("Debug Current Root") {
              public void actionPerformed(ActionEvent e) {
                Project project = ProjectHelper.toIdeaProject(myOperationContext.getProject());
                Editor currentEditor =
                    EditorsHelper.getSelectedEditors(FileEditorManager.getInstance(project)).get(0);
                if (currentEditor != null) {
                  EditorComponent editorComponent = currentEditor.getCurrentEditorComponent();
                  if (editorComponent != null) {
                    final SNode currentRoot = editorComponent.getEditedNode();
                    debugRoot(currentRoot);
                  }
                }
              }
            });
    JPanel upperPanel = new JPanel();
    upperPanel.setLayout(new GridBagLayout());
    GridBagConstraints upperPanelConstraints = new GridBagConstraints();
    upperPanelConstraints.gridx = 0;
    upperPanelConstraints.gridy = 0;
    upperPanelConstraints.weightx = 0;
    upperPanelConstraints.weighty = 0;
    upperPanelConstraints.anchor = GridBagConstraints.NORTHWEST;
    upperPanel.add(debugCurrentRootButton, upperPanelConstraints);

    String text = "no info collected";
    upperPanelConstraints.gridx = 1;
    upperPanel.add(new JLabel(text));

    upperPanelConstraints.weightx = 1;
    upperPanelConstraints.gridx = 2;
    upperPanel.add(new JPanel(), upperPanelConstraints);

    add(upperPanel, gridBagConstraints);

    JPanel innerPanel = new JPanel(new GridBagLayout());

    int y = 0;
    GridBagConstraints innerConstraints = new GridBagConstraints();

    if (myNodeToSliceWith != null) {
      // initial node type

      innerConstraints.gridy = y;
      y++;
      innerConstraints.weighty = 0;
      innerConstraints.weightx = 0;
      innerConstraints.fill = GridBagConstraints.NONE;
      innerConstraints.anchor = GridBagConstraints.NORTHWEST;

      innerConstraints.gridx = 0;
      innerPanel.add(new JLabel("initial type: "), innerConstraints);

      innerConstraints.gridx = 1;
      innerConstraints.gridwidth = GridBagConstraints.REMAINDER;
      SNodeTree initialTypeTree = new SNodeTree(null);
      innerPanel.add(initialTypeTree, innerConstraints);
      initialTypeTree.rebuildNow();

      // innerPanel.add(nodeTypePanel, gridBagConstraints);

      // slice items
      innerConstraints.gridwidth = 1;

      for (EquationLogItem equationLogItem : myCurrentSlice) {
        innerConstraints.gridy = y;
        addEquationLog(innerPanel, innerConstraints, equationLogItem);
        // innerPanel.add(new EquationLogItemPanel(equationLogItem), gridBagConstraints);
        y++;
      }
    }

    innerConstraints.gridy = y;
    innerConstraints.weighty = 1;
    JPanel gauge = new JPanel();
    gauge.setBackground(Color.WHITE);
    innerPanel.add(gauge, innerConstraints);

    innerPanel.setBackground(Color.WHITE);
    JScrollPane scrollPane = ScrollPaneFactory.createScrollPane(innerPanel);
    scrollPane.setBackground(Color.WHITE);

    gridBagConstraints.weighty = 1;
    gridBagConstraints.gridy = 1;
    add(scrollPane, gridBagConstraints);
  }