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.internal.ui.refactoring.actions;
  
  import org.eclipse.core.runtime.Assert;
  import org.eclipse.core.runtime.CoreException;
  import org.eclipse.jface.dialogs.MessageDialog;
  import org.eclipse.jface.text.ITextSelection;
  import org.eclipse.jface.viewers.IStructuredSelection;
  import org.eclipse.ui.IWorkbenchSite;
  import org.eclipse.ui.PlatformUI;
  import org.eclipse.wst.jsdt.core.IJavaScriptUnit;
  import org.eclipse.wst.jsdt.core.IJavaScriptElement;
  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.corext.refactoring.RefactoringExecutionStarter;
  import org.eclipse.wst.jsdt.internal.corext.util.JavaModelUtil;
  import org.eclipse.wst.jsdt.internal.ui.IJavaHelpContextIds;
  import org.eclipse.wst.jsdt.internal.ui.JavaScriptPlugin;
  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.javaeditor.JavaTextSelection;
  import org.eclipse.wst.jsdt.internal.ui.refactoring.RefactoringMessages;
  import org.eclipse.wst.jsdt.internal.ui.util.ExceptionHandler;
  import org.eclipse.wst.jsdt.ui.actions.SelectionDispatchAction;
  
  public final class MoveInstanceMethodAction extends SelectionDispatchAction {
  
  	private JavaEditor fEditor;
  	
  	/**
  	 * Note: This constructor is for internal use only. Clients should not call this constructor.
  	 * @param editor the java editor
  	 */
  	public MoveInstanceMethodAction(JavaEditor editor) {
  		this(editor.getEditorSite());
  		fEditor= editor;
  		setEnabled(SelectionConverter.canOperateOn(fEditor));
  	}
  
  	public MoveInstanceMethodAction(IWorkbenchSite site) {
  		super(site);
  		setText(RefactoringMessages.MoveInstanceMethodAction_Move_Method); 
  		PlatformUI.getWorkbench().getHelpSystem().setHelp(this, IJavaHelpContextIds.MOVE_ACTION);		
  	}
  
  	/*
  	 * @see SelectionDispatchAction#selectionChanged(IStructuredSelection)
  	 */
  	public void selectionChanged(IStructuredSelection selection) {
  		try {
  			setEnabled(RefactoringAvailabilityTester.isMoveMethodAvailable(selection));
  		} catch (JavaScriptModelException e) {
  			// http://bugs.eclipse.org/bugs/show_bug.cgi?id=19253
  			if (JavaModelUtil.isExceptionToBeLogged(e))
  				JavaScriptPlugin.log(e);
  			setEnabled(false);//no ui
  		}
  	}
  
  	public void selectionChanged(ITextSelection selection) {
  		setEnabled(true);
      }
  
  	/**
  	 * Note: This method is for internal use only. Clients should not call this method.
  	 */
  	public void selectionChanged(JavaTextSelection selection) {
  		try {
  			setEnabled(RefactoringAvailabilityTester.isMoveMethodAvailable(selection));
  		} catch (CoreException e) {
  			setEnabled(false);
  		}
  	}
  	
  	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;
  	}
  	/*
  	 * @see SelectionDispatchAction#run(IStructuredSelection)
  	 */
  	public void run(IStructuredSelection selection) {		
  		try {
  			Assert.isTrue(RefactoringAvailabilityTester.isMoveMethodAvailable(selection));
  			IFunction method= getSingleSelectedMethod(selection);
  			Assert.isNotNull(method);
  			if (!ActionUtil.isEditable(fEditor, getShell(), method))
  				return;
  			RefactoringExecutionStarter.startMoveMethodRefactoring(method, getShell());
  		} catch (JavaScriptModelException e) {
  			ExceptionHandler.handle(e, getShell(), RefactoringMessages.MoveInstanceMethodAction_dialog_title, RefactoringMessages.MoveInstanceMethodAction_unexpected_exception);	 
  		}
   	}	
  	
  	/* (non-Javadoc)
  	 * Method declared on SelectionDispatchAction
  	 */		
  	public void run(ITextSelection selection) {
  		try {
  			run(selection, SelectionConverter.getInputAsCompilationUnit(fEditor));
  		} catch (JavaScriptModelException e) {
  			ExceptionHandler.handle(e, getShell(), RefactoringMessages.MoveInstanceMethodAction_dialog_title, RefactoringMessages.MoveInstanceMethodAction_unexpected_exception);	 
  		}
  	}
  
  	private void run(ITextSelection selection, IJavaScriptUnit cu) throws JavaScriptModelException {
  		Assert.isNotNull(cu);
  		Assert.isTrue(selection.getOffset() >= 0);
  		Assert.isTrue(selection.getLength() >= 0);
  
  		if (!ActionUtil.isEditable(fEditor, getShell(), cu))
  			return;
  
  		IFunction method= getMethod(cu, selection);
  		if (method != null) {
  			RefactoringExecutionStarter.startMoveMethodRefactoring(method, getShell());
  		} else {
  			MessageDialog.openInformation(getShell(), RefactoringMessages.MoveInstanceMethodAction_dialog_title, RefactoringMessages.MoveInstanceMethodAction_No_reference_or_declaration); 
  		}
  	}
  
  	private static IFunction getMethod(IJavaScriptUnit cu, ITextSelection selection) throws JavaScriptModelException {
  		IJavaScriptElement element= SelectionConverter.getElementAtOffset(cu, selection);
  		if (element instanceof IFunction)
  			return (IFunction) element;
  		return null;
  	}
  }
  