/* Copyright 2004, 2005, 2006 Acegi Technology Pty Limited
 *
 * Licensed 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 org.acegisecurity.ui.basicauth;

import java.io.IOException;
import java.util.Map;

import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletResponse;

import org.acegisecurity.AuthenticationException;
import org.acegisecurity.ui.AuthenticationEntryPoint;
import org.acegisecurity.util.OrderedUtils;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.core.Ordered;
import org.springframework.util.Assert;

/**
 * Used by the <code>SecurityEnforcementFilter</code> to commence
 * authentication via the {@link BasicProcessingFilter}.
 * <P>
 * Once a user agent is authenticated using BASIC authentication, logout
 * requires that the browser be closed or an unauthorized (401) header be sent.
 * The simplest way of achieving the latter is to call the
 * {@link #commence(ServletRequest, ServletResponse, AuthenticationException)}
 * method below. This will indicate to the browser its credentials are no longer
 * authorized, causing it to prompt the user to login again.
 * </p>
 * 
 * @author Ben Alex
 * @version $Id: BasicProcessingFilterEntryPoint.java 1822 2007-05-17 12:20:16Z
 * vishalpuri $
 */
public class BasicProcessingFilterEntryPoint implements AuthenticationEntryPoint, InitializingBean, Ordered,
		ApplicationContextAware {
	// ~ Static fields/initializers
	// =====================================================================================
	private static final int DEFAULT_ORDER = Integer.MAX_VALUE;

	// ~ Instance fields
	// ================================================================================================

	private String realmName;

	private int order = DEFAULT_ORDER;

	private ApplicationContext applicationContext;

	// ~ Methods
	// ========================================================================================================

	public int getOrder() {
		return order;
	}

	public void setOrder(int order) {
		this.order = order;
	}

	public void afterPropertiesSet() throws Exception {
		Assert.hasText(realmName, "realmName must be specified");
		if (order == DEFAULT_ORDER) {
			OrderedUtils.copyOrderFromOtherClass(BasicProcessingFilter.class, applicationContext, this, true);
		}
	}

	public void commence(ServletRequest request, ServletResponse response, AuthenticationException authException)
			throws IOException, ServletException {
		HttpServletResponse httpResponse = (HttpServletResponse) response;
		httpResponse.addHeader("WWW-Authenticate", "Basic realm=\"" + realmName + "\"");
		httpResponse.sendError(HttpServletResponse.SC_UNAUTHORIZED, authException.getMessage());
	}

	public String getRealmName() {
		return realmName;
	}

	public void setRealmName(String realmName) {
		this.realmName = realmName;
	}

	public void setApplicationContext(ApplicationContext applicationContext) {
		this.applicationContext = applicationContext;
	}
}