Copyright (c) 2004, 2009 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) 2004, 2009 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.core.util;

import org.eclipse.jdt.core.util.ClassFormatException;
import org.eclipse.jdt.core.util.IConstantPool;
import org.eclipse.jdt.core.util.IConstantPoolConstant;
import org.eclipse.jdt.core.util.IConstantPoolEntry;
import org.eclipse.jdt.core.util.IVerificationTypeInfo;

public class VerificationInfo extends ClassFileStruct implements IVerificationTypeInfo {

	private int tag;
	private int offset;
	private int constantPoolIndex;
	private char[] classTypeName;
	private int readOffset;

	public VerificationInfo(
			byte[] classFileBytes,
			IConstantPool constantPool,
			int offset) throws ClassFormatException {
		final int t = u1At(classFileBytes, 0, offset);
		this.tag = t;
		this.readOffset = 1;
		switch(t) {
			case IVerificationTypeInfo.ITEM_OBJECT :
				final int constantIndex = u2At(classFileBytes, 1, offset);
				this.constantPoolIndex = constantIndex;
				if (constantIndex != 0) {
					IConstantPoolEntry constantPoolEntry = constantPool.decodeEntry(constantIndex);
					if (constantPoolEntry.getKind() != IConstantPoolConstant.CONSTANT_Class) {
						throw new ClassFormatException(ClassFormatException.INVALID_CONSTANT_POOL_ENTRY);
					}
					this.classTypeName = constantPoolEntry.getClassInfoName();
				}
				this.readOffset += 2;
				break;
			case IVerificationTypeInfo.ITEM_UNINITIALIZED :
				this.offset = u2At(classFileBytes, 1, offset);
				this.readOffset += 2;
		}
	}

	@Override
	public int getTag() {
		return this.tag;
	}

	@Override
	public int getOffset() {
		return this.offset;
	}

	@Override
	public int getConstantPoolIndex() {
		return this.constantPoolIndex;
	}

	@Override
	public char[] getClassTypeName() {
		return this.classTypeName;
	}

	public int sizeInBytes() {
		return this.readOffset;
	}
}