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.corext.refactoring.changes;
  
  import org.eclipse.core.resources.IFile;
  import org.eclipse.core.resources.IResource;
  import org.eclipse.core.runtime.Assert;
  import org.eclipse.core.runtime.CoreException;
  import org.eclipse.core.runtime.IProgressMonitor;
  import org.eclipse.core.runtime.SubProgressMonitor;
  import org.eclipse.ltk.core.refactoring.Change;
  import org.eclipse.ltk.core.refactoring.NullChange;
  import org.eclipse.ltk.core.refactoring.RefactoringStatus;
  import org.eclipse.ui.ide.undo.ResourceDescription;
  import org.eclipse.wst.jsdt.core.IJavaScriptUnit;
  import org.eclipse.wst.jsdt.core.IJavaScriptElement;
  import org.eclipse.wst.jsdt.core.IPackageFragment;
  import org.eclipse.wst.jsdt.core.ISourceManipulation;
  import org.eclipse.wst.jsdt.core.JavaScriptCore;
  import org.eclipse.wst.jsdt.internal.corext.refactoring.RefactoringCoreMessages;
  import org.eclipse.wst.jsdt.internal.corext.refactoring.util.JavaElementUtil;
  import org.eclipse.wst.jsdt.internal.corext.util.Messages;
  
  /**
   * Caveat: undo of package fragment deletes is provided by a wrapping
   * UndoablePackageDeleteChange. This change returns a NullChange as undo for package fragments.
   */
  public class DeleteSourceManipulationChange extends AbstractDeleteChange {
  
  	private final String fHandle;
  	private final boolean fIsExecuteChange;
  	
  	public DeleteSourceManipulationChange(ISourceManipulation sm, boolean isExecuteChange) { 
  		Assert.isNotNull(sm);
  		fHandle= getJavaElement(sm).getHandleIdentifier();
  		fIsExecuteChange= isExecuteChange;
  	}
  
  	/*
  	 * @see IChange#getName()
  	 */
  	public String getName() {
  		return Messages.format(RefactoringCoreMessages.DeleteSourceManipulationChange_0, getElementName()); 
  	}
  	
  	public RefactoringStatus isValid(IProgressMonitor pm) throws CoreException {
  		ISourceManipulation element= getSourceManipulation();
  		if (fIsExecuteChange) {
  			if (element instanceof IJavaScriptUnit) {
  				// don't check anything in this case. We have a warning dialog
  				// already presented to the user that the file is dirty.
  				return super.isValid(pm, NONE);
  			} else {
  				return super.isValid(pm, DIRTY);
  			}
  		} else {
  			return super.isValid(pm, READ_ONLY | DIRTY);
  		}
  	}
  
  	private String getElementName() {
  		IJavaScriptElement javaElement= getJavaElement(getSourceManipulation());
  		if (JavaElementUtil.isDefaultPackage(javaElement))
  			return RefactoringCoreMessages.DeleteSourceManipulationChange_1; 
  		return javaElement.getElementName();
  	}
  
  	/*
  	 * @see IChange#getModifiedLanguageElement()
  	 */
  	public Object getModifiedElement() {
  		return JavaScriptCore.create(fHandle);
  	}
  	
  	/*
  	 * @see DeleteChange#doDelete(IProgressMonitor)
  	 */
  	protected Change doDelete(IProgressMonitor pm) throws CoreException {
  		ISourceManipulation element= getSourceManipulation();
  		// we have to save dirty compilation units before deleting them. Otherwise
  		// we will end up showing ghost compilation units in the package explorer
  		// since the primary working copy still exists.
  		if (element instanceof IJavaScriptUnit) {
  			pm.beginTask("", 2); //$NON-NLS-1$
  			IJavaScriptUnit unit= (IJavaScriptUnit)element;
  			saveCUnitIfNeeded(unit, new SubProgressMonitor(pm, 1));
  			
  			IResource resource= unit.getResource();
  			ResourceDescription resourceDescription = ResourceDescription.fromResource(resource);
  			element.delete(false, new SubProgressMonitor(pm, 1));
  			resourceDescription.recordStateFromHistory(resource, new SubProgressMonitor(pm, 1));
  			return new UndoDeleteResourceChange(resourceDescription);
  			
  		} else if (element instanceof IPackageFragment) {
  			IJavaScriptUnit[] units= ((IPackageFragment)element).getJavaScriptUnits();
  			pm.beginTask("", units.length + 1); //$NON-NLS-1$
  			for (int i = 0; i < units.length; i++) {
  				// fix https://bugs.eclipse.org/bugs/show_bug.cgi?id=66835
  				saveCUnitIfNeeded(units[i], new SubProgressMonitor(pm, 1));
  			}
  			element.delete(false, new SubProgressMonitor(pm, 1));
  			return new NullChange(); // caveat: real undo implemented by UndoablePackageDeleteChange
  			
  		} else {
  			element.delete(false, pm);
  			return null; //should not happen
  		}
  	}
  		
  	private ISourceManipulation getSourceManipulation() {
  		return (ISourceManipulation) getModifiedElement();
  	}
  
  	private static IJavaScriptElement getJavaElement(ISourceManipulation sm) {
  		//all known ISourceManipulations are IJavaElements
  		return (IJavaScriptElement)sm;
  	}
  	
  	private static void saveCUnitIfNeeded(IJavaScriptUnit unit, IProgressMonitor pm) throws CoreException {
  		saveFileIfNeeded((IFile)unit.getResource(), pm);
  	}
  }
  
  