/*
 * JBoss, Home of Professional Open Source
 * Copyright 2005-2008, Red Hat Middleware LLC, and individual contributors
 * by the @authors tag. See the copyright.txt in the distribution for a
 * full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */ 

package org.jboss.messaging.core.security.impl;

import java.security.AccessController;
import java.security.Principal;
import java.security.PrivilegedAction;

import javax.security.auth.Subject;

import org.jboss.security.SecurityAssociation;


/** A collection of privileged actions for this package
 * @author Scott.Stark@jboss.org
 * @author <a href="mailto:alex@jboss.org">Alexey Loubyansky</a>
 * @author <a her="mailto:tim.fox@jboss.com">Tim Fox</a>
 * @version $Revison: 1.0$
 */
class SecurityActions
{
	interface PrincipalInfoAction
	{
		PrincipalInfoAction PRIVILEGED = new PrincipalInfoAction()
		{
			public void push(final Principal principal, final Object credential,
					           final Subject subject)
			{
				AccessController.doPrivileged(
						new PrivilegedAction()
						{
							public Object run()
							{
								SecurityAssociation.pushSubjectContext(subject, principal, credential);
								return null;
							}
						}
				);
			}
			public void pop()
			{
				AccessController.doPrivileged(
						new PrivilegedAction()
						{
							public Object run()
							{
								SecurityAssociation.popSubjectContext();
								return null;
							}
						}
				);
			}
		};

		PrincipalInfoAction NON_PRIVILEGED = new PrincipalInfoAction()
		{
			public void push(final Principal principal, final Object credential, final Subject subject)
			{
				SecurityAssociation.pushSubjectContext(subject, principal, credential);
			}
			public void pop()
			{
				SecurityAssociation.popSubjectContext();
			}
		};

		void push(Principal principal, Object credential, Subject subject);
		void pop();
	}

	static void pushSubjectContext(final Principal principal, final Object credential,
			                         final Subject subject)
	{
		if(System.getSecurityManager() == null)
		{
			PrincipalInfoAction.NON_PRIVILEGED.push(principal, credential, subject);
		}
		else
		{
			PrincipalInfoAction.PRIVILEGED.push(principal, credential, subject);
		}
	}
	
	static void popSubjectContext()
	{
		if (System.getSecurityManager() == null)
		{
			PrincipalInfoAction.NON_PRIVILEGED.pop();
		}
		else
		{
			PrincipalInfoAction.PRIVILEGED.pop();
		}
	}
}