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 org.eclipse.core.runtime.Assert;

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



public final class TypeVariable extends AbstractTypeVariable {

	private ITypeParameter fJavaTypeParameter;

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

	protected void initialize(ITypeBinding binding, ITypeParameter javaTypeParameter) {
		Assert.isTrue(binding.isTypeVariable());
		Assert.isNotNull(javaTypeParameter);
		fJavaTypeParameter= javaTypeParameter;
		super.initialize(binding);
	}

	@Override
	public int getKind() {
		return TYPE_VARIABLE;
	}

	@Override
	public boolean doEquals(TType type) {
		return fJavaTypeParameter.equals(((TypeVariable)type).fJavaTypeParameter);
	}

	@Override
	public int hashCode() {
		return fJavaTypeParameter.hashCode();
	}

	@Override
	protected boolean doCanAssignTo(TType lhs) {
		switch (lhs.getKind()) {
			case NULL_TYPE:
			case VOID_TYPE: return false;
			case PRIMITIVE_TYPE:

			case ARRAY_TYPE: return false;

			case GENERIC_TYPE: return false;

			case STANDARD_TYPE:
			case PARAMETERIZED_TYPE:
			case RAW_TYPE:
				return canAssignOneBoundTo(lhs);

			case UNBOUND_WILDCARD_TYPE:
			case EXTENDS_WILDCARD_TYPE:
			case SUPER_WILDCARD_TYPE:
				return ((WildcardType)lhs).checkAssignmentBound(this);

			case TYPE_VARIABLE:
				return doExtends((TypeVariable)lhs);
			case CAPTURE_TYPE:
				return ((CaptureType)lhs).checkLowerBound(this);
		}
		return false;
	}

	private boolean doExtends(TypeVariable other) {
		for (int i= 0; i < fBounds.length; i++) {
			TType bound= fBounds[i];
			if (other.equals(bound) || (bound.getKind() == TYPE_VARIABLE && ((TypeVariable)bound).doExtends(other)))
				return true;
		}
		return false;
	}

	@Override
	public String getName() {
		return fJavaTypeParameter.getElementName();
	}

	@Override
	public String getPrettySignature() {
		if (fBounds.length == 1 && fBounds[0].isJavaLangObject())
			return fJavaTypeParameter.getElementName(); // don't print the trivial bound

		StringBuilder result= new StringBuilder(fJavaTypeParameter.getElementName());
		if (fBounds.length > 0) {
			result.append(" extends "); //$NON-NLS-1$
			result.append(fBounds[0].getPlainPrettySignature());
			for (int i= 1; i < fBounds.length; i++) {
				result.append(" & "); //$NON-NLS-1$
				result.append(fBounds[i].getPlainPrettySignature());
			}
		}
		return result.toString();
	}

	@Override
	protected String getPlainPrettySignature() {
		return fJavaTypeParameter.getElementName();
	}
}