Copyright (c) 2007, 2008 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2007, 2008 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.ltk.core.refactoring.resource;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.NullProgressMonitor;
import org.eclipse.core.runtime.OperationCanceledException;
import org.eclipse.core.runtime.SubProgressMonitor;

import org.eclipse.core.resources.IContainer;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.ResourcesPlugin;

import org.eclipse.ltk.core.refactoring.Change;
import org.eclipse.ltk.core.refactoring.ChangeDescriptor;
import org.eclipse.ltk.core.refactoring.RefactoringStatus;
import org.eclipse.ltk.internal.core.refactoring.BasicElementLabels;
import org.eclipse.ltk.internal.core.refactoring.Messages;
import org.eclipse.ltk.internal.core.refactoring.RefactoringCoreMessages;

Change that moves a resource. 
Since:
3.4/**
 * {@link Change} that moves a resource.
 *
 * @since 3.4
 */
public class MoveResourceChange extends ResourceChange {

	private final IResource fSource;
	private final IContainer fTarget;
	private final long fStampToRestore;
	private final Change fRestoreSourceChange;

	private ChangeDescriptor fDescriptor;

	
Creates the change.
Params:
source – the resource to move
target – the container the resource is moved to. An existing resource at the destination will be
replaced./**
	 * Creates the change.
	 *
	 * @param source the resource to move
	 * @param target the container the resource is moved to. An existing resource at the destination will be
	 * replaced.
	 */
	public MoveResourceChange(IResource source, IContainer target) {
		this(source, target, IResource.NULL_STAMP, null);
	}

	
Creates the change.
Params:
source – the resource to move
target – the container the resource is moved to. An existing resource at the destination will be
replaced.
stampToRestore – the stamp to restore on the moved resource
	@param restoreSourceChange the change to restore a resource at the source or null if no resource
needs to be resourced./**
	 * Creates the change.
	 *
	 * @param source the resource to move
	 * @param target the container the resource is moved to. An existing resource at the destination will be
	 * replaced.
	 * @param stampToRestore the stamp to restore on the moved resource
	 * 	@param restoreSourceChange the change to restore a resource at the source or <code>null</code> if no resource
	 * needs to be resourced.
	 */
	protected MoveResourceChange(IResource source, IContainer target, long stampToRestore, Change restoreSourceChange) {
		fSource= source;
		fTarget= target;
		fStampToRestore= stampToRestore;
		fRestoreSourceChange= restoreSourceChange;

		// We already present a dialog to the user if he
		// moves read-only resources. Since moving a resource
		// doesn't do a validate edit (it actually doesn't
		// change the content we can't check for READ only
		// here.
		setValidationMethod(VALIDATE_NOT_DIRTY);
	}

	@Override
	public ChangeDescriptor getDescriptor() {
		return fDescriptor;
	}

	
Sets the change descriptor to be returned by Change.getDescriptor(). 
Params:
descriptor – the change descriptor/**
	 * Sets the change descriptor to be returned by {@link Change#getDescriptor()}.
	 *
	 * @param descriptor the change descriptor
	 */
	public void setDescriptor(ChangeDescriptor descriptor) {
		fDescriptor= descriptor;
	}

	@Override
	public final Change perform(IProgressMonitor monitor) throws CoreException, OperationCanceledException {
		try {
			if (monitor == null)
				monitor= new NullProgressMonitor();

			monitor.beginTask(getName(), 4);

			Change deleteUndo= null;

			// delete destination if required
			IResource resourceAtDestination= fTarget.findMember(fSource.getName());
			if (resourceAtDestination != null && resourceAtDestination.exists()) {
				deleteUndo= performDestinationDelete(resourceAtDestination, new SubProgressMonitor(monitor, 1));
			} else {
				monitor.worked(1);
			}

			// move resource
			long currentStamp= fSource.getModificationStamp();
			IPath destinationPath= fTarget.getFullPath().append(fSource.getName());
			fSource.move(destinationPath, IResource.KEEP_HISTORY | IResource.SHALLOW, new SubProgressMonitor(monitor, 2));
			resourceAtDestination= ResourcesPlugin.getWorkspace().getRoot().findMember(destinationPath);

			// restore timestamp at destination
			if (fStampToRestore != IResource.NULL_STAMP) {
				resourceAtDestination.revertModificationStamp(fStampToRestore);
			}

			// restore file at source
			if (fRestoreSourceChange != null) {
				performSourceRestore(new SubProgressMonitor(monitor, 1));
			} else {
				monitor.worked(1);
			}
			return new MoveResourceChange(resourceAtDestination, fSource.getParent(), currentStamp, deleteUndo);
		} finally {
			monitor.done();
		}
	}

	private Change performDestinationDelete(IResource newResource, IProgressMonitor monitor) throws CoreException {
		monitor.beginTask(RefactoringCoreMessages.MoveResourceChange_progress_delete_destination, 3);
		try {
			DeleteResourceChange deleteChange= new DeleteResourceChange(newResource.getFullPath(), true);
			deleteChange.initializeValidationData(new SubProgressMonitor(monitor, 1));
			RefactoringStatus deleteStatus= deleteChange.isValid(new SubProgressMonitor(monitor, 1));
			if (!deleteStatus.hasFatalError()) {
				return deleteChange.perform(new SubProgressMonitor(monitor, 1));
			}
			return null;
		} finally {
			monitor.done();
		}
	}

	private void performSourceRestore(IProgressMonitor monitor) throws CoreException {
		monitor.beginTask(RefactoringCoreMessages.MoveResourceChange_progress_restore_source, 3);
		try {
			fRestoreSourceChange.initializeValidationData(new SubProgressMonitor(monitor, 1));
			RefactoringStatus restoreStatus= fRestoreSourceChange.isValid(new SubProgressMonitor(monitor, 1));
			if (!restoreStatus.hasFatalError()) {
				fRestoreSourceChange.perform(new SubProgressMonitor(monitor, 1));
			}
		} finally {
			monitor.done();
		}
	}

	@Override
	protected IResource getModifiedResource() {
		return fSource;
	}

	@Override
	public String getName() {
		return Messages.format(RefactoringCoreMessages.MoveResourceChange_name, new String[] { BasicElementLabels.getPathLabel(fSource.getFullPath(), false), BasicElementLabels.getResourceName(fTarget) });
	}
}