/*
 *  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
 *
 *     http://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.forms;

import org.apache.commons.compress.harmony.pack200.Pack200Exception;
import org.apache.commons.compress.harmony.unpack200.SegmentConstantPool;
import org.apache.commons.compress.harmony.unpack200.bytecode.ByteCode;
import org.apache.commons.compress.harmony.unpack200.bytecode.ClassFileEntry;
import org.apache.commons.compress.harmony.unpack200.bytecode.OperandManager;

/**
 * This class implements the byte code form for those bytecodes which have class references (and only class references).
 */
public class ClassRefForm extends ReferenceForm {

    protected boolean widened;

    public ClassRefForm(final int opcode, final String name, final int[] rewrite) {
        super(opcode, name, rewrite);
    }

    public ClassRefForm(final int opcode, final String name, final int[] rewrite, final boolean widened) {
        this(opcode, name, rewrite);
        this.widened = widened;
    }

    @Override
    protected int getOffset(final OperandManager operandManager) {
        return operandManager.nextClassRef();
    }

    @Override
    protected int getPoolID() {
        return SegmentConstantPool.CP_CLASS;
    }

    @Override
    protected void setNestedEntries(final ByteCode byteCode, final OperandManager operandManager, final int offset) throws Pack200Exception {
        // If the offset is not zero, proceed normally.
        if (offset != 0) {
            super.setNestedEntries(byteCode, operandManager, offset - 1);
            return;
        }
        // If the offset is 0, ClassRefForms refer to
        // the current class. Add that as the nested class.
        // (This is true for all bc_classref forms in
        // the spec except for multianewarray, which has
        // its own form.)
        final SegmentConstantPool globalPool = operandManager.globalConstantPool();
        // How do I get this class?
        final ClassFileEntry[] nested = { globalPool.getClassPoolEntry(operandManager.getCurrentClass()) };
        byteCode.setNested(nested);
        byteCode.setNestedPositions(new int[][] { { 0, 2 } });
    }
}
