package fr.ippon.groovy.util;

import groovy.lang.GroovyRuntimeException;
import groovy.util.GroovyMBean;

import java.io.IOException;
import java.lang.reflect.Array;

import javax.management.JMException;
import javax.management.MBeanException;
import javax.management.MBeanServerConnection;
import javax.management.ObjectName;

/**
 * Extension de {@link GroovyMBean} qui convertit les ObjectName reçu du serveur JMX
 * en GroovierMBean et les GroovierMBean envoyé au serveur en ObjectName.
 * 
 * @author Fabien Arrault
 */
public class GroovierMBean extends GroovyMBean {

	// TODO : quel doit être la valeur par défaut ?
	public static boolean EXPAND_OBJECTNAME_COLLECTION = true;

	public GroovierMBean(MBeanServerConnection server, ObjectName name) throws JMException, IOException {
		super(server, name);
	}

	public GroovierMBean(MBeanServerConnection server, String name) throws JMException, IOException {
		super(server, name);
	}

	public GroovierMBean mbean(String objectName) throws NullPointerException, JMException, IOException {
		return mbean(new ObjectName(objectName));
	}

	public GroovierMBean mbean(ObjectName objectName) throws JMException, IOException {
		return new GroovierMBean(server(), objectName);
	}

	@Override
	public Object getProperty(String property) {
		Object result = super.getProperty(property);

		result = convertObjectNameToMBean(result);

		return result;
	}

	@Override
	public void setProperty(String property, Object value) {
		value = convertMBeanToObjectName(value);
		super.setProperty(property, value);
	}

	@Override
	public Object invokeMethod(String method, Object arguments) {

		if (arguments instanceof Object[]) {
			Object[] argArray = (Object[]) arguments;
			for (int i = 0; i < argArray.length; i++) {
				argArray[i] = convertMBeanToObjectName(argArray[i]);
			}
		} else {
			arguments = convertMBeanToObjectName(arguments);
		}

		Object result = super.invokeMethod(method, arguments);

		result = convertObjectNameToMBean(result);

		return result;
	}

	private Object convertMBeanToObjectName(Object value) {
		if (value instanceof GroovyMBean) {
			value = ((GroovyMBean) value).name();
		}
		return value;
	}

	private Object convertObjectNameToMBean(Object result) {
		try {
			if (result instanceof ObjectName) {
				result = mbean((ObjectName) result);
			} else if (result != null && EXPAND_OBJECTNAME_COLLECTION) {
				if (result.getClass().isArray()) {
					Class<?> componentType = result.getClass().getComponentType();
					if (ObjectName.class.isAssignableFrom(componentType)) {
						// TODO il faudrait aussi vérifier que la dimension est bien 1 ...

						// conversion :
						int len = Array.getLength(result);
						Object newArray = Array.newInstance(GroovierMBean.class, len);
						for (int i = 0; i < len; i++) {
							ObjectName objectName = (ObjectName) Array.get(result, i);
							Array.set(newArray, i, mbean(objectName));
						}
						result = newArray;
					}
				}
				// TODO : gérer Collection<ObjectName> aussi ?
			}

		} catch (MBeanException e) {
			throwExceptionWithTarget("Converting ObjectName result : " + result + " to WebLoMbean", e);
		} catch (Exception e) {
			throwException("Converting ObjectName result : " + result + " to WebLoMbean", e);
		}

		return result;
	}

	private void throwException(String m, Exception e) {
		throw new GroovyRuntimeException(m + e, e);
	}

	private void throwExceptionWithTarget(String m, MBeanException e) {
		throw new GroovyRuntimeException(m + e, e.getTargetException());
	}

}