ParentChecker.java

/*******************************************************************************
 * Copyright (c) 2000, 2017 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
 *
 *******************************************************************************/
package org.eclipse.dltk.internal.corext.refactoring.reorg;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.core.resources.IResource;
import org.eclipse.core.runtime.Assert;
import org.eclipse.dltk.core.DLTKCore;
import org.eclipse.dltk.core.IModelElement;

public class ParentChecker {
	private IResource[] fResources;
	private IModelElement[] fScriptElements;

	public ParentChecker(IResource[] resources, IModelElement[] modelElements) {
		Assert.isNotNull(resources);
		Assert.isNotNull(modelElements);
		fResources = resources;
		fScriptElements = modelElements;
	}

	public boolean haveCommonParent() {
		return getCommonParent() != null;
	}

	public Object getCommonParent() {
		if (fScriptElements.length == 0 && fResources.length == 0)
			return null;
		if (!resourcesHaveCommonParent() || !modelElementsHaveCommonParent())
			return null;
		if (fScriptElements.length == 0) {
			IResource commonResourceParent = getCommonResourceParent();
			Assert.isNotNull(commonResourceParent);
			IModelElement convertedToScript = DLTKCore
					.create(commonResourceParent);
			if (convertedToScript != null && convertedToScript.exists())
				return convertedToScript;
			else
				return commonResourceParent;
		}
		if (fResources.length == 0)
			return getCommonScriptElementParent();

		IResource commonResourceParent = getCommonResourceParent();
		IModelElement commonScriptElementParent = getCommonScriptElementParent();
		Assert.isNotNull(commonScriptElementParent);
		Assert.isNotNull(commonResourceParent);
		IModelElement convertedToScript = DLTKCore.create(commonResourceParent);
		if (convertedToScript == null || !convertedToScript.exists()
				|| !commonScriptElementParent.equals(convertedToScript))
			return null;
		return commonScriptElementParent;
	}

	private IModelElement getCommonScriptElementParent() {
		Assert.isNotNull(fScriptElements);
		Assert.isTrue(fScriptElements.length > 0);// safe - checked before
		return fScriptElements[0].getParent();
	}

	private IResource getCommonResourceParent() {
		Assert.isNotNull(fResources);
		Assert.isTrue(fResources.length > 0);// safe - checked before
		return fResources[0].getParent();
	}

	private boolean modelElementsHaveCommonParent() {
		if (fScriptElements.length == 0)
			return true;
		IModelElement firstParent = fScriptElements[0].getParent();
		Assert.isNotNull(firstParent); // this should never happen
		for (int i = 1; i < fScriptElements.length; i++) {
			if (!firstParent.equals(fScriptElements[i].getParent()))
				return false;
		}
		return true;
	}

	private boolean resourcesHaveCommonParent() {
		if (fResources.length == 0)
			return true;
		IResource firstParent = fResources[0].getParent();
		Assert.isNotNull(firstParent);
		for (int i = 1; i < fResources.length; i++) {
			if (!firstParent.equals(fResources[i].getParent()))
				return false;
		}
		return true;
	}

	public IResource[] getResources() {
		return fResources;
	}

	public IModelElement[] getScriptElements() {
		return fScriptElements;
	}

	public void removeElementsWithAncestorsOnList(
			boolean removeOnlyScriptElements) {
		if (!removeOnlyScriptElements) {
			removeResourcesDescendantsOfResources();
			removeResourcesDescendantsOfScriptElements();
		}
		removeScriptElementsDescendantsOfScriptElements();
		// removeScriptElementsChildrenOfResources(); //this case is covered by
		// removeUnconfirmedArchives
	}

	private void removeResourcesDescendantsOfScriptElements() {
		List<IResource> subResources = new ArrayList<>(3);
		for (int i = 0; i < fResources.length; i++) {
			IResource subResource = fResources[i];
			for (int j = 0; j < fScriptElements.length; j++) {
				IModelElement superElements = fScriptElements[j];
				if (isDescendantOf(subResource, superElements))
					subResources.add(subResource);
			}
		}
		removeFromSetToDelete(
				subResources.toArray(new IResource[subResources.size()]));
	}

	private void removeScriptElementsDescendantsOfScriptElements() {
		List<IModelElement> subElements = new ArrayList<>(3);
		for (int i = 0; i < fScriptElements.length; i++) {
			IModelElement subElement = fScriptElements[i];
			for (int j = 0; j < fScriptElements.length; j++) {
				IModelElement superElement = fScriptElements[j];
				if (isDescendantOf(subElement, superElement))
					subElements.add(subElement);
			}
		}
		removeFromSetToDelete(
				subElements.toArray(new IModelElement[subElements.size()]));
	}

	private void removeResourcesDescendantsOfResources() {
		List<IResource> subResources = new ArrayList<>(3);
		for (int i = 0; i < fResources.length; i++) {
			IResource subResource = fResources[i];
			for (int j = 0; j < fResources.length; j++) {
				IResource superResource = fResources[j];
				if (isDescendantOf(subResource, superResource))
					subResources.add(subResource);
			}
		}
		removeFromSetToDelete(
				subResources.toArray(new IResource[subResources.size()]));
	}

	public static boolean isDescendantOf(IResource subResource,
			IModelElement superElement) {
		IResource parent = subResource.getParent();
		while (parent != null) {
			IModelElement el = DLTKCore.create(parent);
			if (el != null && el.exists() && el.equals(superElement))
				return true;
			parent = parent.getParent();
		}
		return false;
	}

	public static boolean isDescendantOf(IModelElement subElement,
			IModelElement superElement) {
		if (subElement.equals(superElement))
			return false;
		IModelElement parent = subElement.getParent();
		while (parent != null) {
			if (parent.equals(superElement))
				return true;
			parent = parent.getParent();
		}
		return false;
	}

	public static boolean isDescendantOf(IResource subResource,
			IResource superResource) {
		return !subResource.equals(superResource) && superResource.getFullPath()
				.isPrefixOf(subResource.getFullPath());
	}

	private void removeFromSetToDelete(IResource[] resourcesToNotDelete) {
		fResources = ReorgUtils.setMinus(fResources, resourcesToNotDelete);
	}

	private void removeFromSetToDelete(IModelElement[] elementsToNotDelete) {
		fScriptElements = ReorgUtils.setMinus(fScriptElements,
				elementsToNotDelete);
	}
}