core/plugins/org.eclipse.dltk.ui/core refactoring/org/eclipse/dltk/internal/corext/refactoring/changes/ResourceReorgChange.java

/*******************************************************************************
 * Copyright (c) 2000, 2018 IBM Corporation and others.
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 * 
 * SPDX-License-Identifier: EPL-2.0
 *
 *******************************************************************************/
package org.eclipse.dltk.internal.corext.refactoring.changes;

import org.eclipse.core.resources.IContainer;
import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IFolder;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.SubProgressMonitor;
import org.eclipse.dltk.internal.corext.refactoring.base.DLTKChange;
import org.eclipse.dltk.internal.corext.refactoring.reorg.INewNameQuery;
import org.eclipse.dltk.internal.corext.refactoring.reorg.ReorgUtils;
import org.eclipse.ltk.core.refactoring.Change;
import org.eclipse.ltk.core.refactoring.participants.ReorgExecutionLog;

abstract class ResourceReorgChange extends DLTKChange {

	private final IPath fResourcePath;
	private final boolean fIsFile;
	private final IPath fDestinationPath;
	private final boolean fIsDestinationProject;
	private final INewNameQuery fNewNameQuery;

	ResourceReorgChange(IResource res, IContainer dest,
			INewNameQuery nameQuery) {
		Assert.isTrue(res instanceof IFile || res instanceof IFolder);
		fIsFile = (res instanceof IFile);
		fResourcePath = Utils.getResourcePath(res);

		Assert.isTrue(dest instanceof IProject || dest instanceof IFolder);
		fIsDestinationProject = (dest instanceof IProject);
		fDestinationPath = Utils.getResourcePath(dest);
		fNewNameQuery = nameQuery;
	}

	protected abstract Change doPerformReorg(IPath path, IProgressMonitor pm)
			throws CoreException;

	@Override
	public final Change perform(IProgressMonitor pm) throws CoreException {
		try {
			pm.beginTask(getName(), 2);

			String newName = getNewResourceName();
			IResource resource = getResource();
			boolean performReorg = deleteIfAlreadyExists(
					new SubProgressMonitor(pm, 1), newName);
			if (!performReorg)
				return null;
			final Change result = doPerformReorg(getDestinationPath(newName),
					new SubProgressMonitor(pm, 1));
			markAsExecuted(resource);
			return result;
		} finally {
			pm.done();
		}
	}

	protected IPath getDestinationPath(String newName) {
		return getDestination().getFullPath().append(newName);
	}

	/**
	 * returns false if source and destination are the same (in workspace or on
	 * disk) in such case, no action should be performed
	 */
	private boolean deleteIfAlreadyExists(IProgressMonitor pm, String newName)
			throws CoreException {
		pm.beginTask("", 1); //$NON-NLS-1$
		IResource current = getDestination().findMember(newName);
		if (current == null)
			return true;
		if (!current.exists())
			return true;

		IResource resource = getResource();
		Assert.isNotNull(resource);

		if (ReorgUtils.areEqualInWorkspaceOrOnDisk(resource, current))
			return false;

		if (current instanceof IFile)
			((IFile) current).delete(false, true,
					new SubProgressMonitor(pm, 1));
		else if (current instanceof IFolder)
			((IFolder) current).delete(false, true,
					new SubProgressMonitor(pm, 1));
		else
			Assert.isTrue(false);

		return true;
	}

	private String getNewResourceName() {
		if (fNewNameQuery == null)
			return getResource().getName();
		String name = fNewNameQuery.getNewName();
		if (name == null)
			return getResource().getName();
		return name;
	}

	@Override
	public Object getModifiedElement() {
		return getResource();
	}

	private IFile getFile() {
		return Utils.getFile(fResourcePath);
	}

	private IFolder getFolder() {
		return Utils.getFolder(fResourcePath);
	}

	protected IResource getResource() {
		if (fIsFile) {
			return getFile();
		}
		return getFolder();
	}

	IContainer getDestination() {
		if (fIsDestinationProject) {
			return Utils.getProject(fDestinationPath);
		}
		return Utils.getFolder(fDestinationPath);
	}

	protected int getReorgFlags() {
		return IResource.KEEP_HISTORY | IResource.SHALLOW;
	}

	private void markAsExecuted(IResource resource) {
		ReorgExecutionLog log = getAdapter(ReorgExecutionLog.class);
		if (log != null) {
			log.markAsProcessed(resource);
		}
	}
}