ConditionSection.java

package org.jbpm.gd.jpdl.properties;

import org.eclipse.draw2d.ColorConstants;
import org.eclipse.jface.util.IPropertyChangeListener;
import org.eclipse.jface.util.PropertyChangeEvent;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.CCombo;
import org.eclipse.swt.events.FocusEvent;
import org.eclipse.swt.events.FocusListener;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.layout.FormAttachment;
import org.eclipse.swt.layout.FormData;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Text;
import org.eclipse.ui.IWorkbenchPart;
import org.eclipse.ui.views.properties.tabbed.TabbedPropertySheetPage;
import org.jbpm.gd.common.notation.AbstractNotationElement;
import org.jbpm.gd.common.part.NotationElementGraphicalEditPart;
import org.jbpm.gd.common.part.OutlineEditPart;
import org.jbpm.gd.common.properties.AbstractPropertySection;
import org.jbpm.gd.jpdl.Plugin;
import org.jbpm.gd.jpdl.model.Condition;
import org.jbpm.gd.jpdl.model.Decision;
import org.jbpm.gd.jpdl.model.Transition;
import org.jbpm.gd.jpdl.prefs.CompatibilityPage;


public class ConditionSection extends AbstractPropertySection implements SelectionListener, FocusListener {
	
	private Label conditionLabel;
	private CCombo conditionCombo;	
	private Label label;
	private Text expressionText;
	private Text scriptText;
	private Transition transition;

  private static final String CONDITION_ON_TRANSITION_WARNING = "Invalid condition: transitions with conditions only valid if the source node is a decision!";

  private Label warningLabel;
  private Boolean hideTransitionConditionWarnings;
  
	public void createControls(Composite parent,
            TabbedPropertySheetPage aTabbedPropertySheetPage) {
        super.createControls(parent, aTabbedPropertySheetPage);
        Composite clientArea = getWidgetFactory().createFlatFormComposite(parent);

        warningLabel = getWidgetFactory().createLabel(clientArea, "");
        warningLabel.setForeground(ColorConstants.red);
        conditionLabel = getWidgetFactory().createLabel(clientArea, "Condition Type");
        conditionCombo = getWidgetFactory().createCCombo(clientArea);
        // updateConditionCombo(); -- refresh is always called, and the ConditionCombo is set there.

        conditionCombo.setEditable(false);
        label = getWidgetFactory().createLabel(clientArea, "");
        expressionText = getWidgetFactory().createText(clientArea, "");
        scriptText = getWidgetFactory().createText(clientArea, "", SWT.H_SCROLL | SWT.V_SCROLL);

        warningLabel.setLayoutData(createWarningLabelLayoutData());
        conditionLabel.setLayoutData(createConditionLabelLayoutData());
        conditionCombo.setLayoutData(createConditionComboLayoutData());
        label.setLayoutData(createLabelLayoutData());
        expressionText.setLayoutData(createExpressionTextLayoutData());
        scriptText.setLayoutData(createScriptTextLayoutData());
        hookListeners();
        refresh();
    }

  IPropertyChangeListener preferenceListener = new IPropertyChangeListener() {
    /*
     * @see IPropertyChangeListener.propertyChange()
     */
    public void propertyChange(PropertyChangeEvent event) {
      if (event.getProperty().equals(Plugin.TRANS_COND_WARN_PREFERENCE)) {
         hideTransitionConditionWarnings = null;
      }
    }
  };

	private void hookListeners() {
		conditionCombo.addSelectionListener(this);
		expressionText.addSelectionListener(this);
		expressionText.addFocusListener(this);
		scriptText.addSelectionListener(this);
		scriptText.addFocusListener(this);
    Plugin.getDefault().getPreferenceStore().addPropertyChangeListener(preferenceListener);
	}
  
  public void dispose() {
    Plugin.getDefault().getPreferenceStore().removePropertyChangeListener(preferenceListener);
    super.dispose();
  }
 
  private void updateConditionCombo() {
    if (transition == null) {
      conditionCombo.setItems(new String[] { "Unconditional" });
    }
    else if (getHideTransitionConditionWarning() ) {
      conditionCombo.setItems(new String[] { "Unconditional", "Expression", "Script" });
    }
    else {
      // showTransitionConditionWarning && transition != null
      if( transition.getSource() instanceof Decision ) {
        conditionCombo.setItems(new String[] { "Unconditional", "Expression", "Script" });
      }
      else if (transition.getCondition() != null ) {
        // backwards compatibility, warning will be shown
        if (transition.getCondition().getExpression() != null) {
          conditionCombo.setItems(new String[] { "Unconditional", "Expression" });
        }
        else if (transition.getCondition().getScript() != null) {
          conditionCombo.setItems(new String[] { "Unconditional", "Script" });
        }
      }
      else {
        conditionCombo.setItems(new String[] { "Unconditional" });
      }
    }
  }

  private void updateWarningLabel() {
    if( getHideTransitionConditionWarning() ) {
      warningLabel.setText("");
    }
    else if (transition == null 
             || transition.getCondition() == null
             || transition.getSource() == null 
             || transition.getSource() instanceof Decision) {
      warningLabel.setText("");
    }
    else if (transition.getCondition() != null && !(transition.getSource() instanceof Decision)) {
      warningLabel.setText(CONDITION_ON_TRANSITION_WARNING);
    }
    else {
      warningLabel.setText("");
    }
  }
 
  private FormData createWarningLabelLayoutData() {
    FormData result = new FormData();
    result.left = new FormAttachment(0, 5);
    result.right = new FormAttachment(100, -5);
    result.top = new FormAttachment(conditionCombo, 10);
    return result;
  }
  
	private FormData createConditionLabelLayoutData() {
		FormData result = new FormData();
		result.left = new FormAttachment(0, 5);
		result.top = new FormAttachment(0, 5);
		return result;
	}
	
	private FormData createConditionComboLayoutData() {
		FormData result = new FormData();
		result.left = new FormAttachment(conditionLabel, 5);
		result.top = new FormAttachment(0, 5);
		return result;
	}
	
	private FormData createLabelLayoutData() {
		FormData result = new FormData();
		result.left = new FormAttachment(0, 5);
		result.right = new FormAttachment(100, -5);
    result.top = new FormAttachment(warningLabel, 10);
		return result;
	}
	
	private FormData createExpressionTextLayoutData() {
		FormData result = new FormData();
		result.left = new FormAttachment(0, 5);
		result.right = new FormAttachment(100, -5);
		result.top = new FormAttachment(label, 0);
		return result;
	}
	
	private FormData createScriptTextLayoutData() {
		FormData result = new FormData();
		result.left = new FormAttachment(0, 5);
		result.right = new FormAttachment(100, -5);
		result.top = new FormAttachment(label, 0);
		result.height = 100;
		return result;
	}
	
 	public void setInput(IWorkbenchPart part, ISelection selection) {
        super.setInput(part, selection);
        if (!(selection instanceof IStructuredSelection)) return;
        Object input = ((IStructuredSelection)selection).getFirstElement();
        if (input instanceof NotationElementGraphicalEditPart) {
        	AbstractNotationElement notationElement = ((NotationElementGraphicalEditPart)input).getNotationElement();
        	input = notationElement.getSemanticElement();
        } else if (input instanceof OutlineEditPart) {
        	input = ((OutlineEditPart)input).getModel();
        }
        if (input instanceof Transition) {
        	transition = (Transition)input;
        	refresh();
        }
    }
 	
 	public void refresh() {
    updateConditionCombo();
    updateWarningLabel();
 		if (transition == null || transition.getCondition() == null){
 			conditionCombo.setText("Unconditional");
			label.setText("");
			expressionText.setText("");
			expressionText.setVisible(false);
			scriptText.setText("");
			scriptText.setVisible(false);
 		} else {
 			Condition condition = transition.getCondition();
 			if (condition != null && condition.getExpression() != null) {
 				conditionCombo.setText("Expression");
 				label.setText("Condition");
 				expressionText.setText(condition.getExpression());
 				expressionText.setVisible(true);
 				scriptText.setText("");
 				scriptText.setVisible(false);
 			} else if (condition != null && condition.getScript() != null) {
 				conditionCombo.setText("Script");
 				label.setText("Script");
 				scriptText.setText(condition.getScript());
 				scriptText.setVisible(true);
 				expressionText.setText("");
 				expressionText.setVisible(false);
 			} else {
 				conditionCombo.setText("Unknown");
 				label.setText("");
 				expressionText.setVisible(false);
 				scriptText.setVisible(false);
 			}
 		}
 	}
 	
	public boolean shouldUseExtraSpace() {
		return true;
	}
		
	public void widgetDefaultSelected(SelectionEvent e) {
		if (e.widget == expressionText) {
			handleExpressionTextChanged();
		} else if (e.widget == scriptText) {
			handleScriptTextChanged();
		}		
	}
	
	private void handleExpressionTextChanged() {
		if (transition != null && transition.getCondition() != null) {
			transition.getCondition().setExpression(expressionText.getText());
		}
	}

	private void handleScriptTextChanged() {
		if (transition != null && transition.getCondition() != null) {
			transition.getCondition().setScript(scriptText.getText());
		}
	}

	public void widgetSelected(SelectionEvent e) {
		if (e.widget == conditionCombo) {
			handleConditionComboSelected();
		}
	}
	
	private void handleConditionComboSelected() {
		if ("Expression".equals(conditionCombo.getText())) {
      updateWarningLabel();
			label.setText("Expression");
			scriptText.setVisible(false);
			expressionText.setVisible(true);
			if (transition != null) {
				updateCondition();
			}
		} else if ("Script".equals(conditionCombo.getText())) {
      updateWarningLabel();
			label.setText("Script");
			expressionText.setVisible(false);
			scriptText.setVisible(true);
			if (transition != null) {
				updateCondition();
			}
		} else {
		  warningLabel.setText("");
			label.setText("");
			expressionText.setVisible(false);
			scriptText.setVisible(false);
			if (transition != null) {
				transition.setCondition(null);
			}
		}
	}
	
	private void updateCondition() {
		Condition condition = transition.getCondition();
		if (condition == null) {
			condition = (Condition)transition.getFactory().createById("org.jbpm.gd.jpdl.condition");
			transition.setCondition(condition);
		}
		if ("Expression".equals(conditionCombo.getText())) {
			condition.setScript(null);
			condition.setExpression(expressionText.getText());
		} else if ("Script".equals(conditionCombo.getText())) {
			condition.setExpression(null);
			condition.setScript(scriptText.getText());
		}
	}

	public void focusGained(FocusEvent e) {
	}

	public void focusLost(FocusEvent e) {
		if (e.widget == expressionText) {
			handleExpressionTextChanged();
		} else if (e.widget == scriptText) {
			handleScriptTextChanged();
		}		
	}
	
  private Boolean getHideTransitionConditionWarning() {
    if (hideTransitionConditionWarnings == null) {
      hideTransitionConditionWarnings = Plugin.getDefault().getPreferenceStore()
        .getBoolean(Plugin.TRANS_COND_WARN_PREFERENCE);
    }
    return hideTransitionConditionWarnings;
  }

}