/*
* 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 com.dragome.callbackevictor.serverside.bytecode.transformation.asm;

import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;

import com.dragome.callbackevictor.enhancers.Continuable;

public final class ContinuationClassAdapter extends ClassVisitor
{

	private String className;

	public ContinuationClassAdapter(final ClassVisitor cv)
	{
		super(Opcodes.ASM5, cv);
	}

	public void visit(int version, int access, String name, String signature, String superName, String[] interfaces)
	{
		className= name;

		// Check that it doesn't implement Continuable (already been instrumented)
		String[] newInterfaces= new String[interfaces.length + 1];
		for (int i= 0; i < interfaces.length; i++)
		{
			if (interfaces[i].equals(Type.getInternalName(Continuable.class)))
			{
				throw new RuntimeException(className + " has already been instrumented");
			}

			newInterfaces[i]= interfaces[i];
		}

		// Add the Continuable interface so that the class is marked and wont be instrumented again by mistake
		newInterfaces[newInterfaces.length - 1]= Type.getInternalName(Continuable.class);

		cv.visit(version, access, name, signature, superName, newInterfaces);
	}

	public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions)
	{
		MethodVisitor mv= super.visitMethod(access, name, desc, signature, exceptions);
		// TODO skip native and abstract methods?
		if (!"<init>".equals(name) && mv != null)
		{
			return new ContinuationMethodAnalyzer(className, this.cv, mv, access, name, desc, signature, exceptions);
		}
		return mv;
	}

}