content: /*******************************************************************************
   * Copyright (c) 2000, 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.jsdt.ui.actions;
  
  import java.util.Arrays;
  import java.util.HashSet;
  import java.util.Iterator;
  import java.util.Set;
  
  import org.eclipse.jface.dialogs.MessageDialog;
  import org.eclipse.jface.text.ITextSelection;
  import org.eclipse.jface.viewers.ISelection;
  import org.eclipse.jface.viewers.IStructuredSelection;
  import org.eclipse.jface.viewers.SelectionChangedEvent;
  import org.eclipse.jface.viewers.StructuredSelection;
  import org.eclipse.ui.IWorkbenchSite;
  import org.eclipse.ui.PlatformUI;
  import org.eclipse.wst.jsdt.core.IJavaScriptElement;
  import org.eclipse.wst.jsdt.core.IMember;
  import org.eclipse.wst.jsdt.core.IFunction;
  import org.eclipse.wst.jsdt.core.JavaScriptModelException;
  import org.eclipse.wst.jsdt.internal.corext.refactoring.RefactoringAvailabilityTester;
  import org.eclipse.wst.jsdt.internal.ui.IJavaHelpContextIds;
  import org.eclipse.wst.jsdt.internal.ui.actions.ActionUtil;
  import org.eclipse.wst.jsdt.internal.ui.actions.SelectionConverter;
  import org.eclipse.wst.jsdt.internal.ui.javaeditor.JavaEditor;
  import org.eclipse.wst.jsdt.internal.ui.refactoring.RefactoringMessages;
  import org.eclipse.wst.jsdt.internal.ui.refactoring.actions.MoveInstanceMethodAction;
  import org.eclipse.wst.jsdt.internal.ui.refactoring.actions.MoveStaticMembersAction;
  import org.eclipse.wst.jsdt.internal.ui.refactoring.reorg.ReorgMoveAction;
  import org.eclipse.wst.jsdt.internal.ui.util.ExceptionHandler;
  
  /**
   * This action moves JavaScript elements to a new location. The action prompts
   * the user for the new location.
   * <p>
   * The action is applicable to a homogeneous selection containing either
   * projects, package fragment roots, package fragments, compilation units,
   * or static methods.
   * 
   * <p>
   * This class may be instantiated; it is not intended to be subclassed.
   * </p>
   * 
   *
   * Provisional API: This class/interface is part of an interim API that is still under development and expected to
   * change significantly before reaching stability. It is being made available at this early stage to solicit feedback
   * from pioneering adopters on the understanding that any code that uses this API will almost certainly be broken
   * (repeatedly) as the API evolves.
   */
  public class MoveAction extends SelectionDispatchAction{
  //TODO: remove duplicate availability checks. Look at
  //- f...Action.selectionChanged
  //- f...Action.isEnabled
  //- ...Refactoring.isAvailable
  //- try...
  //... and remove duplicated code for text/structured selections.
  //We have to clean this up, once we have a long term solution to
  //bug 35748 (no JavaElements for local types). 
  	
  	private JavaEditor fEditor;
  	private MoveInstanceMethodAction fMoveInstanceMethodAction;
  	private MoveStaticMembersAction fMoveStaticMembersAction;
  	private ReorgMoveAction fReorgMoveAction;
  	
  	/**
  	 * Creates a new <code>MoveAction</code>. The action requires
  	 * that the selection provided by the site's selection provider is of type <code>
  	 * org.eclipse.jface.viewers.IStructuredSelection</code>.
  	 * 
  	 * @param site the site providing context information for this action
  	 */
  	public MoveAction(IWorkbenchSite site) {
  		super(site);
  		setText(RefactoringMessages.MoveAction_text); 
  		fMoveStaticMembersAction= new MoveStaticMembersAction(site);
  		fMoveInstanceMethodAction= new MoveInstanceMethodAction(site);
  		fReorgMoveAction= new ReorgMoveAction(site);
  		PlatformUI.getWorkbench().getHelpSystem().setHelp(this, IJavaHelpContextIds.MOVE_ACTION);
  	}
  	
  	/**
  	 * Note: This constructor is for internal use only. Clients should not call this constructor.
  	 * @param editor the JavaScript editor
  	 */
  	public MoveAction(JavaEditor editor) {
  		super(editor.getEditorSite());
  		fEditor= editor;
  		setText(RefactoringMessages.MoveAction_text); 
  		fMoveStaticMembersAction= new MoveStaticMembersAction(editor);
  		fMoveInstanceMethodAction= new MoveInstanceMethodAction(editor);
  		fReorgMoveAction= new ReorgMoveAction(editor.getEditorSite());
  		PlatformUI.getWorkbench().getHelpSystem().setHelp(this, IJavaHelpContextIds.MOVE_ACTION);
  	}	
  
  	/*
  	 * @see ISelectionChangedListener#selectionChanged(SelectionChangedEvent)
  	 */
  	public void selectionChanged(SelectionChangedEvent event) {
  		fMoveStaticMembersAction.selectionChanged(event);
  		fMoveInstanceMethodAction.selectionChanged(event);
  		fReorgMoveAction.selectionChanged(event);
  		setEnabled(computeEnableState());	
  	}
  
  	/*
  	 * @see org.eclipse.wst.jsdt.ui.actions.SelectionDispatchAction#run(org.eclipse.jface.viewers.IStructuredSelection)
  	 */
  	public void run(IStructuredSelection selection) {
  		try {
  			if (fMoveInstanceMethodAction.isEnabled() && tryMoveInstanceMethod(selection)) 
  				return;
  	
  			if (fMoveStaticMembersAction.isEnabled() && tryMoveStaticMembers(selection)) 
  				return;
  	
  			if (fReorgMoveAction.isEnabled())
  				fReorgMoveAction.run();
  		
  		} catch (JavaScriptModelException e) {
  			ExceptionHandler.handle(e, RefactoringMessages.OpenRefactoringWizardAction_refactoring, RefactoringMessages.OpenRefactoringWizardAction_exception); 
  		}
  
  	}
  
  	/*
  	 * @see org.eclipse.wst.jsdt.ui.actions.SelectionDispatchAction#run(org.eclipse.jface.text.ITextSelection)
  	 */
  	public void run(ITextSelection selection) {
  		try {
  			if (!ActionUtil.isEditable(fEditor))
  				return;
  			if (fMoveStaticMembersAction.isEnabled() && tryMoveStaticMembers(selection))
  				return;
  		
  			if (fMoveInstanceMethodAction.isEnabled() && tryMoveInstanceMethod(selection))
  				return;
  	
  			if (tryReorgMove(selection))
  				return;
  			
  			MessageDialog.openInformation(getShell(), RefactoringMessages.MoveAction_Move, RefactoringMessages.MoveAction_select); 
  		} catch (JavaScriptModelException e) {
  			ExceptionHandler.handle(e, RefactoringMessages.OpenRefactoringWizardAction_refactoring, RefactoringMessages.OpenRefactoringWizardAction_exception); 
  		}
  	}
  
  	private boolean tryMoveStaticMembers(ITextSelection selection) throws JavaScriptModelException {
  		IJavaScriptElement element= SelectionConverter.getElementAtOffset(fEditor);
  		if (element == null || !(element instanceof IMember))
  			return false;
  		IMember[] array= new IMember[] { (IMember) element};
  		if (!RefactoringAvailabilityTester.isMoveStaticMembersAvailable(array))
  			return false;
  		fMoveStaticMembersAction.run(selection);
  		return true;
  	}
  
  	private static IMember[] getSelectedMembers(IStructuredSelection selection){
  		if (selection.isEmpty())
  			return null;
  		
  		for  (Iterator iter= selection.iterator(); iter.hasNext(); ) {
  			if (! (iter.next() instanceof IMember))
  				return null;
  		}
  		return convertToMemberArray(selection.toArray());
  	}
  
  	private static IMember[] convertToMemberArray(Object[] obj) {
  		if (obj == null)
  			return null;
  		Set memberSet= new HashSet();
  		memberSet.addAll(Arrays.asList(obj));
  		return (IMember[]) memberSet.toArray(new IMember[memberSet.size()]);
  	}
  
  	private boolean tryMoveStaticMembers(IStructuredSelection selection) throws JavaScriptModelException {
  		IMember[] array= getSelectedMembers(selection);
  		if (!RefactoringAvailabilityTester.isMoveStaticMembersAvailable(array))
  			return false;
  		fMoveStaticMembersAction.run(selection);
  		return true;
  	}
  
  	private boolean tryMoveInstanceMethod(ITextSelection selection) throws JavaScriptModelException {
  		IJavaScriptElement element= SelectionConverter.getElementAtOffset(fEditor);
  		if (element == null || !(element instanceof IFunction))
  			return false;
  
  		IFunction method= (IFunction) element;
  		if (!RefactoringAvailabilityTester.isMoveMethodAvailable(method))
  			return false;
  		fMoveInstanceMethodAction.run(selection);
  		return true;
  	}
  
  	private boolean tryMoveInstanceMethod(IStructuredSelection selection) throws JavaScriptModelException {
  		IFunction method= getSingleSelectedMethod(selection);
  		if (method == null)
  			return false;
  		if (!RefactoringAvailabilityTester.isMoveMethodAvailable(method))
  			return false;
  		fMoveInstanceMethodAction.run(selection);
  		return true;
  	}
  
  	private static IFunction getSingleSelectedMethod(IStructuredSelection selection) {
  		if (selection.isEmpty() || selection.size() != 1) 
  			return null;
  		
  		Object first= selection.getFirstElement();
  		if (! (first instanceof IFunction))
  			return null;
  		return (IFunction) first;
  	}
  	
  
  	private boolean tryReorgMove(ITextSelection selection) throws JavaScriptModelException{
  		IJavaScriptElement element= SelectionConverter.getElementAtOffset(fEditor);
  		if (element == null)
  			return false;
  		StructuredSelection mockStructuredSelection= new StructuredSelection(element);
  		fReorgMoveAction.selectionChanged(mockStructuredSelection);
  		if (!fReorgMoveAction.isEnabled())
  			return false;
  			
  		fReorgMoveAction.run(mockStructuredSelection);
  		return true;			
  	}
  
  
  	/*
  	 * @see SelectionDispatchAction#update(ISelection)
  	 */
  	public void update(ISelection selection) {
  		fMoveStaticMembersAction.update(selection);
  		fMoveInstanceMethodAction.update(selection);
  		fReorgMoveAction.update(selection);
  		setEnabled(computeEnableState());
  	}
  	
  	private boolean computeEnableState(){
  		return fMoveStaticMembersAction.isEnabled()
  				|| fMoveInstanceMethodAction.isEnabled()
  				|| fReorgMoveAction.isEnabled();
  	}
  }
  