/*
 * Copyright 2002-2017 the original author or authors.
 *
 * 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.springframework.security.web.authentication.logout;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.security.core.Authentication;
import org.springframework.security.web.util.UrlUtils;
import org.springframework.util.Assert;

/**
 * {@link LogoutSuccessHandler} implementation that will perform a request dispatcher
 * "forward" to the specified target URL.
 *
 * @author Vedran Pavic
 * @since 5.0
 */
public class ForwardLogoutSuccessHandler implements LogoutSuccessHandler {

	private final String targetUrl;

	/**
	 * Construct a new {@link ForwardLogoutSuccessHandler} with the given target URL.
	 * @param targetUrl the target URL
	 */
	public ForwardLogoutSuccessHandler(String targetUrl) {
		Assert.isTrue(UrlUtils.isValidRedirectUrl(targetUrl), "'" + targetUrl
				+ "' is not a valid target URL");
		this.targetUrl = targetUrl;
	}

	@Override
	public void onLogoutSuccess(HttpServletRequest request, HttpServletResponse response,
			Authentication authentication) throws IOException, ServletException {
		request.getRequestDispatcher(this.targetUrl).forward(request, response);
	}

}
