/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.commons.compress.harmony.unpack200.bytecode;

import java.io.DataOutputStream;
import java.io.IOException;

/**
 * Enclosing method class file attribute.
 */
public class EnclosingMethodAttribute extends Attribute {

    private static CPUTF8 attributeName;

    public static void setAttributeName(final CPUTF8 cpUTF8Value) {
        attributeName = cpUTF8Value;
    }

    private int classIndex;
    private int methodIndex;
    private final CPClass cpClass;

    private final CPNameAndType method;

    /**
     * Constructs a new instance.
     *
     * @param cpClass a constant pool class.
     * @param method a constant pool name and type.
     */
    public EnclosingMethodAttribute(final CPClass cpClass, final CPNameAndType method) {
        super(attributeName);
        this.cpClass = cpClass;
        this.method = method;
    }

    /*
     * (non-Javadoc)
     *
     * @see org.apache.commons.compress.harmony.unpack200.bytecode.Attribute#getLength()
     */
    @Override
    protected int getLength() {
        return 4;
    }

    @Override
    protected ClassFileEntry[] getNestedClassFileEntries() {
        if (method != null) {
            return new ClassFileEntry[] { attributeName, cpClass, method };
        }
        return new ClassFileEntry[] { attributeName, cpClass };
    }

    @Override
    protected void resolve(final ClassConstantPool pool) {
        super.resolve(pool);
        cpClass.resolve(pool);
        classIndex = pool.indexOf(cpClass);
        if (method != null) {
            method.resolve(pool);
            methodIndex = pool.indexOf(method);
        } else {
            methodIndex = 0;
        }
    }

    /*
     * (non-Javadoc)
     *
     * @see org.apache.commons.compress.harmony.unpack200.bytecode.ClassFileEntry#toString()
     */
    @Override
    public String toString() {
        return "EnclosingMethod";
    }

    /*
     * (non-Javadoc)
     *
     * @see org.apache.commons.compress.harmony.unpack200.bytecode.Attribute#writeBody(java.io.DataOutputStream)
     */
    @Override
    protected void writeBody(final DataOutputStream dos) throws IOException {
        dos.writeShort(classIndex);
        dos.writeShort(methodIndex);
    }

}
