/*******************************************************************************
 *  Copyright (c) 2012 Google, Inc.
 *  All rights reserved. This program and the accompanying materials
 *  are made available under the terms of the Eclipse Public License v1.0
 *  which accompanies this distribution, and is available at
 *  http://www.eclipse.org/legal/epl-v10.html
 *  
 *  Contributors:
 *  Google, Inc. - initial API and implementation
 *******************************************************************************/
package com.windowtester.internal.runtime.util;

import java.lang.reflect.Array;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;


/**
 * Simple reflection utilities.
 */
public class ReflectionUtils {

	@SuppressWarnings("unchecked")
	public static <T> T newInstance(T obj) throws IllegalArgumentException, SecurityException, InstantiationException, IllegalAccessException, InvocationTargetException, NoSuchMethodException{
		Object newObj = obj.getClass().getConstructor().newInstance();
		return (T)newObj;
	}
	
	@SuppressWarnings("unchecked")
	public static <T> T newInstance(T obj, Class<?> argType, Object arg) throws IllegalArgumentException, SecurityException, InstantiationException, IllegalAccessException, InvocationTargetException, NoSuchMethodException{
		Object newObj = obj.getClass().getConstructor(argType).newInstance(arg);
		return (T)newObj;
	}
	
	@SuppressWarnings("unchecked")
	public static <T> T newInstance(Class<?> instanceClass, Class<?> argType, Object arg) throws IllegalArgumentException, SecurityException, InstantiationException, IllegalAccessException, InvocationTargetException, NoSuchMethodException{
		Object newObj = instanceClass.getConstructor(argType).newInstance(arg);
		return (T)newObj;
	}
	
	
	public static <T> T[] newArray(T[] a, int size){
		return newArray(getComponentType(a), size);
	}
	
	@SuppressWarnings("unchecked")
	public static <T> Class<? extends T> getComponentType(T[] a) {
		Class<?> k = a.getClass().getComponentType();
		return (Class<? extends T>)k;
	}
	
	@SuppressWarnings("unchecked")
	public static <T> T[] newArray(Class<? extends T> k, int size) {
		if (k.isPrimitive())
			throw new IllegalArgumentException("Argument cannot be primitive: " + k);
		Object a = Array.newInstance(k, size);
		return (T[])a;
	}
	
	
	@SuppressWarnings("unchecked")
	public static <T> T castTo(Object o, Class<T> cls) {
		Class<? extends Object> oc = o.getClass();
		if (cls.isAssignableFrom(oc))
			return (T)o;
		System.out.println("ReflectionUtils.castTo() -- returning null");
		return null;
	}
	
	public static boolean instanceOf(Object o, Class<?> cls){
		Invariants.notNull(o, cls);
		return cls.isInstance(o);
	}
	
	public static Object invoke(Object object, String methodName)
			throws NoSuchMethodException, IllegalAccessException,
			InvocationTargetException {
		Class<?> objectClass = object.getClass();
		Method method;
		try {
			method = objectClass.getMethod(methodName, new Class<?>[] {});
		} catch (NoSuchMethodException e) {
			method = objectClass.getDeclaredMethod(methodName,
					new Class<?>[] {});
			method.setAccessible(true);
		}
		return method.invoke(object, new Object[] {});
	}
	
	
	
}