/*

 * Copyright (c) 2013, 2018, Oracle and/or its affiliates. All rights reserved.

 * 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

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package jdk.jfr.internal.instrument;

import java.lang.reflect.Method;

import java.lang.reflect.Modifier;

import java.util.List;

import jdk.internal.org.objectweb.asm.ClassReader;

import jdk.internal.org.objectweb.asm.ClassVisitor;

import jdk.internal.org.objectweb.asm.MethodVisitor;

import jdk.internal.org.objectweb.asm.Opcodes;

import jdk.internal.org.objectweb.asm.Type;

import jdk.internal.org.objectweb.asm.tree.ClassNode;

import jdk.internal.org.objectweb.asm.tree.MethodNode;

import jdk.jfr.internal.LogLevel;

import jdk.jfr.internal.LogTag;

import jdk.jfr.internal.Logger;

@Deprecated

final class JIInliner extends ClassVisitor {

    private final String targetClassName;

    private final String instrumentationClassName;

    private final ClassNode targetClassNode;

    private final List<Method> instrumentationMethods;

    /**

     * A ClassVisitor which will check all methods of the class it visits against the instrumentationMethods

     * list. If a method is on that list, the method will be further processed for inlining into that

     * method.

     */

    JIInliner(int api, ClassVisitor cv, String targetClassName, String instrumentationClassName,

            ClassReader targetClassReader,

            List<Method> instrumentationMethods) {

        super(api, cv);

        this.targetClassName = targetClassName;

        this.instrumentationClassName = instrumentationClassName;

        this.instrumentationMethods = instrumentationMethods;

        ClassNode cn = new ClassNode(Opcodes.ASM5);

        targetClassReader.accept(cn, ClassReader.EXPAND_FRAMES);

        this.targetClassNode = cn;

    }

    @Override

    public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {

        MethodVisitor mv = super.visitMethod(access, name, desc, signature, exceptions);

        if (isInstrumentationMethod(name, desc)) {

            MethodNode methodToInline = findTargetMethodNode(name, desc);

            if (methodToInline == null) {

                throw new IllegalArgumentException("Could not find the method to instrument in the target class");

            }

            if (Modifier.isNative(methodToInline.access)) {

                throw new IllegalArgumentException("Cannot instrument native methods: " + targetClassNode.name + "." + methodToInline.name + methodToInline.desc);

            }

            Logger.log(LogTag.JFR_SYSTEM_BYTECODE, LogLevel.DEBUG, "Inliner processing method " + name + desc);

            JIMethodCallInliner mci = new JIMethodCallInliner(access,

                    desc,

                    mv,

                    methodToInline,

                    targetClassName,

                    instrumentationClassName);

            return mci;

        }

        return mv;

    }

    private boolean isInstrumentationMethod(String name, String desc) {

        for(Method m : instrumentationMethods) {

            if (m.getName().equals(name) && Type.getMethodDescriptor(m).equals(desc)) {

                return true;

            }

        }

        return false;

    }

    private MethodNode findTargetMethodNode(String name, String desc) {

        for (MethodNode mn : targetClassNode.methods) {

            if (mn.desc.equals(desc) && mn.name.equals(name)) {

                return mn;

            }

        }

        throw new IllegalArgumentException("could not find MethodNode for "

                + name + desc);

    }

}