/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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/*
 * This file is available under and governed by the GNU General Public
 * License version 2 only, as published by the Free Software Foundation.
 * However, the following notice accompanied the original version of this
 * file:
 *
 * ASM: a very small and fast Java bytecode manipulation framework
 * Copyright (c) 2000-2011 INRIA, France Telecom
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

package jdk.internal.org.objectweb.asm.tree;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import jdk.internal.org.objectweb.asm.MethodVisitor;
import jdk.internal.org.objectweb.asm.Opcodes;

/**
 * A node that represents a stack map frame. These nodes are pseudo instruction nodes in order to be
 * inserted in an instruction list. In fact these nodes must(*) be inserted <i>just before</i> any
 * instruction node <b>i</b> that follows an unconditionnal branch instruction such as GOTO or
 * THROW, that is the target of a jump instruction, or that starts an exception handler block. The
 * stack map frame types must describe the values of the local variables and of the operand stack
 * elements <i>just before</i> <b>i</b> is executed. <br>
 * <br>
 * (*) this is mandatory only for classes whose version is greater than or equal to {@link
 * Opcodes#V1_6}.
 *
 * @author Eric Bruneton
 */
public class FrameNode extends AbstractInsnNode {

    /**
      * The type of this frame. Must be {@link Opcodes#F_NEW} for expanded frames, or {@link
      * Opcodes#F_FULL}, {@link Opcodes#F_APPEND}, {@link Opcodes#F_CHOP}, {@link Opcodes#F_SAME} or
      * {@link Opcodes#F_APPEND}, {@link Opcodes#F_SAME1} for compressed frames.
      */
    public int type;

    /**
      * The types of the local variables of this stack map frame. Elements of this list can be Integer,
      * String or LabelNode objects (for primitive, reference and uninitialized types respectively -
      * see {@link MethodVisitor}).
      */
    public List<Object> local;

    /**
      * The types of the operand stack elements of this stack map frame. Elements of this list can be
      * Integer, String or LabelNode objects (for primitive, reference and uninitialized types
      * respectively - see {@link MethodVisitor}).
      */
    public List<Object> stack;

    private FrameNode() {
        super(-1);
    }

    /**
      * Constructs a new {@link FrameNode}.
      *
      * @param type the type of this frame. Must be {@link Opcodes#F_NEW} for expanded frames, or
      *     {@link Opcodes#F_FULL}, {@link Opcodes#F_APPEND}, {@link Opcodes#F_CHOP}, {@link
      *     Opcodes#F_SAME} or {@link Opcodes#F_APPEND}, {@link Opcodes#F_SAME1} for compressed frames.
      * @param numLocal number of local variables of this stack map frame.
      * @param local the types of the local variables of this stack map frame. Elements of this list
      *     can be Integer, String or LabelNode objects (for primitive, reference and uninitialized
      *     types respectively - see {@link MethodVisitor}).
      * @param numStack number of operand stack elements of this stack map frame.
      * @param stack the types of the operand stack elements of this stack map frame. Elements of this
      *     list can be Integer, String or LabelNode objects (for primitive, reference and
      *     uninitialized types respectively - see {@link MethodVisitor}).
      */
    public FrameNode(
            final int type,
            final int numLocal,
            final Object[] local,
            final int numStack,
            final Object[] stack) {
        super(-1);
        this.type = type;
        switch (type) {
            case Opcodes.F_NEW:
            case Opcodes.F_FULL:
                this.local = Util.asArrayList(numLocal, local);
                this.stack = Util.asArrayList(numStack, stack);
                break;
            case Opcodes.F_APPEND:
                this.local = Util.asArrayList(numLocal, local);
                break;
            case Opcodes.F_CHOP:
                this.local = Util.asArrayList(numLocal);
                break;
            case Opcodes.F_SAME:
                break;
            case Opcodes.F_SAME1:
                this.stack = Util.asArrayList(1, stack);
                break;
            default:
                throw new IllegalArgumentException();
        }
    }

    @Override
    public int getType() {
        return FRAME;
    }

    @Override
    public void accept(final MethodVisitor methodVisitor) {
        switch (type) {
            case Opcodes.F_NEW:
            case Opcodes.F_FULL:
                methodVisitor.visitFrame(type, local.size(), asArray(local), stack.size(), asArray(stack));
                break;
            case Opcodes.F_APPEND:
                methodVisitor.visitFrame(type, local.size(), asArray(local), 0, null);
                break;
            case Opcodes.F_CHOP:
                methodVisitor.visitFrame(type, local.size(), null, 0, null);
                break;
            case Opcodes.F_SAME:
                methodVisitor.visitFrame(type, 0, null, 0, null);
                break;
            case Opcodes.F_SAME1:
                methodVisitor.visitFrame(type, 0, null, 1, asArray(stack));
                break;
            default:
                throw new IllegalArgumentException();
        }
    }

    @Override
    public AbstractInsnNode clone(final Map<LabelNode, LabelNode> clonedLabels) {
        FrameNode clone = new FrameNode();
        clone.type = type;
        if (local != null) {
            clone.local = new ArrayList<>();
            for (int i = 0, n = local.size(); i < n; ++i) {
                Object localElement = local.get(i);
                if (localElement instanceof LabelNode) {
                    localElement = clonedLabels.get(localElement);
                }
                clone.local.add(localElement);
            }
        }
        if (stack != null) {
            clone.stack = new ArrayList<>();
            for (int i = 0, n = stack.size(); i < n; ++i) {
                Object stackElement = stack.get(i);
                if (stackElement instanceof LabelNode) {
                    stackElement = clonedLabels.get(stackElement);
                }
                clone.stack.add(stackElement);
            }
        }
        return clone;
    }

    private static Object[] asArray(final List<Object> list) {
        Object[] array = new Object[list.size()];
        for (int i = 0, n = array.length; i < n; ++i) {
            Object o = list.get(i);
            if (o instanceof LabelNode) {
                o = ((LabelNode) o).getLabel();
            }
            array[i] = o;
        }
        return array;
    }
}

