package com.infomancers.collections.yield.asmtree.enhancers;

import com.infomancers.collections.yield.asmbase.YielderInformationContainer;
import com.infomancers.collections.yield.asmtree.CodeStack;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.tree.*;

import java.util.List;

/**
 * Copyright (c) 2009, Aviad Ben Dov
 * <p/>
 * All rights reserved.
 * <p/>
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 * <p/>
 * 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 Infomancers, Ltd. nor the names of its contributors may be
 * used to endorse or promote products derived from this software without specific
 * prior written permission.
 * <p/>
 * 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.
 */

public class MethodInvocationEnhancer implements PredicatedInsnEnhancer {
    public AbstractInsnNode enhance(ClassNode clz, InsnList instructions, List<AbstractInsnNode> limits, YielderInformationContainer info, AbstractInsnNode instruction) {
        MethodInsnNode method = (MethodInsnNode) instruction;

        int targetStack = method.desc.endsWith("V") ? -1 : 0;

        AbstractInsnNode load = CodeStack.backUntilStackSizedAt(instruction, targetStack, false, limits);
        instructions.insert(load, new TypeInsnNode(Opcodes.CHECKCAST, method.owner));

        return instruction;
    }

    public boolean shouldEnhance(AbstractInsnNode node) {
        if (node.getType() == AbstractInsnNode.METHOD_INSN && node.getOpcode() != Opcodes.INVOKESTATIC) {
            MethodInsnNode method = (MethodInsnNode) node;

            return !"java/lang/Object".equals(method.owner);
        } else {
            return false;
        }
    }
}