content: /*******************************************************************************
   * Copyright (c) 2000, 2007 IBM Corporation and others.
   * All rights reserved. This program and the accompanying materials
   * are made available under the terms of the Eclipse Public License v1.0
   * which accompanies this distribution, and is available at
   * http://www.eclipse.org/legal/epl-v10.html
   *
   * Contributors:
   *     IBM Corporation - initial API and implementation
   *******************************************************************************/
  package org.eclipse.wst.jsdt.internal.ui.actions;
  
  import org.eclipse.jface.text.IRegion;
  import org.eclipse.jface.text.ITextSelection;
  import org.eclipse.jface.text.ITextViewerExtension5;
  import org.eclipse.jface.text.Region;
  import org.eclipse.jface.text.source.ISourceViewer;
  import org.eclipse.swt.custom.StyledText;
  import org.eclipse.swt.graphics.Point;
  import org.eclipse.wst.jsdt.internal.ui.javaeditor.JavaEditor;
  import org.eclipse.wst.jsdt.internal.ui.text.JavaWordFinder;
  
  
  public abstract class JDTQuickMenuAction extends QuickMenuAction { 
  	
  	private JavaEditor fEditor;
  	
  	public JDTQuickMenuAction(String commandId) {
  		super(commandId);
  	}
  
  	public JDTQuickMenuAction(JavaEditor editor, String commandId) {
  		super(commandId);
  		fEditor= editor;
  	}
  
  	protected Point computeMenuLocation(StyledText text) {
  		if (fEditor == null || text != fEditor.getViewer().getTextWidget())
  			return null;
  		return computeWordStart();
  	}
  	
  	private Point computeWordStart() {
  		ITextSelection selection= (ITextSelection)fEditor.getSelectionProvider().getSelection();
  		IRegion textRegion= JavaWordFinder.findWord(fEditor.getViewer().getDocument(), selection.getOffset());
  		if (textRegion == null)
  			return null;
  				
  		IRegion widgetRegion= modelRange2WidgetRange(textRegion);
  		if (widgetRegion == null)
  			return null;
  		
  		int start= widgetRegion.getOffset();
  				
  		StyledText styledText= fEditor.getViewer().getTextWidget();
  		Point result= styledText.getLocationAtOffset(start);
  		result.y+= styledText.getLineHeight(start);
  		
  		if (!styledText.getClientArea().contains(result))
  			return null;
  		return result;
  	}
  	
  	private IRegion modelRange2WidgetRange(IRegion region) {
  		ISourceViewer viewer= fEditor.getViewer();
  		if (viewer instanceof ITextViewerExtension5) {
  			ITextViewerExtension5 extension= (ITextViewerExtension5)viewer;
  			return extension.modelRange2WidgetRange(region);
  		}
  		
  		IRegion visibleRegion= viewer.getVisibleRegion();
  		int start= region.getOffset() - visibleRegion.getOffset();
  		int end= start + region.getLength();
  		if (end > visibleRegion.getLength())
  			end= visibleRegion.getLength();
  			
  		return new Region(start, end - start);
  	}	
  }
  