Copyright (c) 2000, 2016 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) 2000, 2016 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.jdt.internal.corext.refactoring.typeconstraints.types;

import java.util.Map;

import org.eclipse.core.runtime.Assert;

import org.eclipse.jdt.core.IType;
import org.eclipse.jdt.core.dom.ITypeBinding;


public abstract class HierarchyType extends TType {
	private HierarchyType fSuperclass;
	private HierarchyType[] fInterfaces;
	private IType fJavaElementType;

	protected HierarchyType(TypeEnvironment environment) {
		super(environment);
	}

	protected void initialize(ITypeBinding binding, IType javaElementType) {
		super.initialize(binding);
		Assert.isNotNull(javaElementType);
		fJavaElementType= javaElementType;
		TypeEnvironment environment= getEnvironment();
		ITypeBinding superclass= binding.getSuperclass();
		if (superclass != null) {
			fSuperclass= (HierarchyType)environment.create(superclass);
		}
		ITypeBinding[] interfaces= binding.getInterfaces();
		fInterfaces= new HierarchyType[interfaces.length];
		for (int i= 0; i < interfaces.length; i++) {
			fInterfaces[i]= (HierarchyType)environment.create(interfaces[i]);
		}
	}

	@Override
	public TType getSuperclass() {
		return fSuperclass;
	}

	@Override
	public TType[] getInterfaces() {
		return fInterfaces;
	}

	public IType getJavaElementType() {
		return fJavaElementType;
	}

	public boolean isSubType(HierarchyType other) {
		if (getEnvironment() == other.getEnvironment()) {
			Map<TypeTuple, Boolean> cache= getEnvironment().getSubTypeCache();
			TypeTuple key= new TypeTuple(this, other);
			Boolean value= cache.get(key);
			if (value != null)
				return value.booleanValue();
			boolean isSub= doIsSubType(other);
			value= Boolean.valueOf(isSub);
			cache.put(key, value);
			return isSub;
		}
		return doIsSubType(other);
	}

	private boolean doIsSubType(HierarchyType other) {
		if (fSuperclass != null && (other.isTypeEquivalentTo(fSuperclass) || fSuperclass.doIsSubType(other)))
			return true;
		for (int i= 0; i < fInterfaces.length; i++) {
			if (other.isTypeEquivalentTo(fInterfaces[i]) || fInterfaces[i].doIsSubType(other))
				return true;
		}
		return false;
	}

	protected boolean canAssignToStandardType(StandardType target) {
		if (target.isJavaLangObject())
			return true;
		return isSubType(target);
	}
}