package org.simantics.scl.compiler.tests.experimentation;

import java.io.PrintWriter;
import java.lang.reflect.Method;
import java.util.concurrent.atomic.AtomicReference;

import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.ClassWriter;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.util.TraceClassVisitor;

public class RecursiveInitialization {

    public static void main(String[] args) throws Exception {
        ClassWriter classWriter = new ClassWriter(ClassWriter.COMPUTE_MAXS);
        ClassVisitor classVisitor = new TraceClassVisitor(classWriter, new PrintWriter(System.out));
        classVisitor.visit(Opcodes.V1_5, Opcodes.ACC_PUBLIC, "test/Test", null, "java/lang/Object", new String[0]);
        MethodVisitor methodWriter = classVisitor.visitMethod(
                Opcodes.ACC_PUBLIC | Opcodes.ACC_STATIC,
                "main", "()Ljava/lang/Object;", null, null);
        
        methodWriter.visitCode();        
        methodWriter.visitTypeInsn(Opcodes.NEW, "java/util/concurrent/atomic/AtomicReference");
        methodWriter.visitVarInsn(Opcodes.ASTORE, 2);

        methodWriter.visitTypeInsn(Opcodes.NEW, "java/util/concurrent/atomic/AtomicReference");
        methodWriter.visitVarInsn(Opcodes.ASTORE, 1);
        
        methodWriter.visitVarInsn(Opcodes.ALOAD, 2);
        methodWriter.visitVarInsn(Opcodes.ALOAD, 1);
        //methodWriter.visitInsn(Opcodes.ACONST_NULL);
        methodWriter.visitMethodInsn(Opcodes.INVOKESPECIAL, "java/util/concurrent/atomic/AtomicReference", "<init>", "(Ljava/lang/Object;)V", false);
        
        methodWriter.visitVarInsn(Opcodes.ALOAD, 1);
        methodWriter.visitVarInsn(Opcodes.ALOAD, 2);
        methodWriter.visitMethodInsn(Opcodes.INVOKESPECIAL, "java/util/concurrent/atomic/AtomicReference", "<init>", "(Ljava/lang/Object;)V", false);

        methodWriter.visitVarInsn(Opcodes.ALOAD, 2);
        methodWriter.visitInsn(Opcodes.ARETURN);
        methodWriter.visitMaxs(0, 0);
        methodWriter.visitEnd();
        
        byte[] bytes = classWriter.toByteArray();
        ClassLoader classLoader = new ClassLoader() {
            @Override
            protected Class<?> findClass(String name) throws ClassNotFoundException {
                if(!name.equals("test.Test"))
                    throw new ClassNotFoundException();
                return defineClass("test.Test", bytes, 0, bytes.length);
            }
        };
        Class<?> clazz = classLoader.loadClass("test.Test");
        Method method = clazz.getMethod("main");
        AtomicReference<Object> result = (AtomicReference<Object>)method.invoke(null);
        System.out.println(result.hashCode());
        //System.out.println(result.get().hashCode());
    }
    
}