/*******************************************************************************
 * Copyright (c) 2000, 2005 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.jdt.internal.corext.refactoring.changes;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.SubProgressMonitor;

import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IResource;

import org.eclipse.core.filebuffers.FileBuffers;
import org.eclipse.core.filebuffers.ITextFileBuffer;

import org.eclipse.jdt.internal.corext.refactoring.RefactoringCoreMessages;
import org.eclipse.jdt.internal.corext.refactoring.base.JDTChange;
import org.eclipse.ltk.core.refactoring.Change;

abstract class AbstractDeleteChange extends JDTChange {
	
	protected abstract void doDelete(IProgressMonitor pm) throws CoreException;
	
	/* non java-doc
	 * @see IChange#perform(ChangeContext, IProgressMonitor)
	 */
	public final Change perform(IProgressMonitor pm) throws CoreException {
		try {
			pm.beginTask(RefactoringCoreMessages.AbstractDeleteChange_deleting, 1); 
			doDelete(pm);
		} finally {
			pm.done();
		}
		return null;
	}
	
	protected static void saveFileIfNeeded(IFile file, IProgressMonitor pm) throws CoreException {
		ITextFileBuffer buffer= FileBuffers.getTextFileBufferManager().getTextFileBuffer(file.getFullPath());
		if (buffer != null && buffer.isDirty() &&  buffer.isStateValidated() && buffer.isSynchronized()) {
			pm.beginTask("", 2); //$NON-NLS-1$
			buffer.commit(new SubProgressMonitor(pm, 1), false);
			file.refreshLocal(IResource.DEPTH_ONE, new SubProgressMonitor(pm, 1));
			pm.done();
		} else {
			pm.beginTask("", 1); //$NON-NLS-1$
			pm.worked(1);
			pm.done();
		}
	}
}