/*******************************************************************************
 * Copyright (c) 2001, 2008 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.wsdl.ui.internal.asd.design;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import org.eclipse.gef.EditPart;
import org.eclipse.gef.SelectionManager;
import org.eclipse.gef.ui.parts.ScrollingGraphicalViewer;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.ISelectionChangedListener;
import org.eclipse.jface.viewers.ISelectionProvider;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.SelectionChangedEvent;
import org.eclipse.jface.viewers.StructuredSelection;
import org.eclipse.ui.IEditorPart;
import org.eclipse.wst.xsd.ui.internal.adt.design.BaseGraphicalViewerKeyHandler;
import org.eclipse.wst.xsd.ui.internal.adt.editor.CommonSelectionManager;

public class DesignViewGraphicalViewer extends ScrollingGraphicalViewer implements ISelectionChangedListener
{
  protected ASDSelectionChangedListener internalSelectionProvider = new ASDSelectionChangedListener();
//TODO Make this generic
	  public DesignViewGraphicalViewer(IEditorPart editor, CommonSelectionManager manager)
	  {
	    super();

	    setContextMenu(new DesignViewContextMenuProvider(this, this));
	    
//	    MenuManager manager = new MenuManager("#popup");
//	    manager.addMenuListener(menuProvider);
//	    manager.setRemoveAllWhenShown(true);
//	    Menu menu = manager.createContextMenu(getControl());
//	    getControl().setMenu(menu);  

	    editor.getEditorSite().registerContextMenu("org.eclipse.wst.wsdl.ui.popup.graph", getContextMenu(), internalSelectionProvider, false); //$NON-NLS-1$

	    // make the internalSelectionProvider listen to graph view selection changes
	    addSelectionChangedListener(internalSelectionProvider);    
	    internalSelectionProvider.addSelectionChangedListener(manager);
	    manager.addSelectionChangedListener(this);  

	    // Workaround bug 227687 An edit part's focus state is not updated properly
	    // Once this is bug is fixed, we can remove custom selection manager
	    setSelectionManager(new CustomSelectionManager());

	    setKeyHandler(new BaseGraphicalViewerKeyHandler(this));
	  }
	  
	  // Workaround bug 227687 An edit part's focus state is not updated properly
	  // Once this is bug is fixed, we can remove this class
	  private class CustomSelectionManager extends SelectionManager
	  {
	    public void appendSelection(EditPart editpart)
	    {
	      if (editpart != getFocus())
	        getViewer().setFocus(editpart);
	      super.appendSelection(editpart);
	    }
	  }
	  
	  // this method is called when something changes in the selection manager
	  // (e.g. a selection occured from another view)
	  public void selectionChanged(SelectionChangedEvent event)
	  {
	    Object selectedObject = ((StructuredSelection) event.getSelection()).getFirstElement();
	    if (event.getSource() != internalSelectionProvider)
	    {
	    	EditPart editPart = getEditPart(getRootEditPart(), selectedObject);
	    	if (editPart != null)
	    	{
	    		setSelection(new StructuredSelection(editPart));
	    	}   
	    }
	  }
	  
	  protected EditPart getEditPart(EditPart editPart, Object model)  
	  {                     
	    EditPart result = null;
	    if (editPart.getModel() == model)
	    {
	      result = editPart;      
	    }                   
	    else
	    {
	      for (Iterator i = editPart.getChildren().iterator(); i.hasNext(); )
	      {
	        result = getEditPart((EditPart)i.next(), model);
	        if (result != null)
	        {
	          break;
	        }
	      }
	    }
	    return result;
	  }
	  

      /*
	   * We need to convert from edit part selections to model object selections
	   */
	  class ASDSelectionChangedListener implements ISelectionProvider, ISelectionChangedListener
	  {
	    protected List listenerList = new ArrayList();
	    protected ISelection selection = new StructuredSelection();

	    public void addSelectionChangedListener(ISelectionChangedListener listener)
	    {
	      listenerList.add(listener);
	    }

	    public void removeSelectionChangedListener(ISelectionChangedListener listener)
	    {
	      listenerList.remove(listener);
	    }

	    public ISelection getSelection()
	    {
	      return selection;
	    }

	    protected void notifyListeners(SelectionChangedEvent event)
	    {
	      for (Iterator i = listenerList.iterator(); i.hasNext();)
	      {
	        ISelectionChangedListener listener = (ISelectionChangedListener) i.next();
	        listener.selectionChanged(event);
	      }
	    }

	    public StructuredSelection convertSelectionFromEditPartToModel(ISelection editPartSelection)
	    {
	      List selectedModelObjectList = new ArrayList();
	      if (editPartSelection instanceof IStructuredSelection)
	      {
	        for (Iterator i = ((IStructuredSelection) editPartSelection).iterator(); i.hasNext();)
	        {
	          Object obj = i.next();
	          Object model = null;
	          if (obj instanceof EditPart)
	          {
	            EditPart editPart = (EditPart) obj;
	            model = editPart.getModel();          
	          }
	          if (model != null)
	          {
	            selectedModelObjectList.add(model);
	          }
	        }
	      }
	      return new StructuredSelection(selectedModelObjectList);
	    }

	    public void setSelection(ISelection selection)
	    {
	      this.selection = selection;
	    }

	    public void selectionChanged(SelectionChangedEvent event)
	    {
	      ISelection newSelection = convertSelectionFromEditPartToModel(event.getSelection());
	      this.selection = newSelection;
	      SelectionChangedEvent newEvent = new SelectionChangedEvent(this, newSelection);
	      notifyListeners(newEvent);
	    }
	  } 
}