/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2012, Red Hat, Inc., and individual contributors
 * as indicated by the @author tags. See the copyright.txt file 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.picketlink.http.authentication;

import org.picketlink.config.http.AuthenticationSchemeConfiguration;
import org.picketlink.credential.DefaultLoginCredentials;

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

/**
 * Basis for the HTTP Authentication Schemes such as BASIC, FORM, DIGEST and CLIENT-CERT. Applications can provide their
 * own authentication schemes by implementing this interface. Implementations must be valid CDI beans, and do support
 * injection.
 *
 * @author Pedro Silva
 * @author Jonathan Fuerth
 * @author Max Barkley
 */
public interface HttpAuthenticationScheme<C extends AuthenticationSchemeConfiguration> {

    /**
     * Called one time during initialization.
     *
     * @param config The configuration.
     */
    void initialize(C config);

    /**
     * Extracts the credentials from the given {@link javax.servlet.http.HttpServletRequest} and populates the
     * {@link org.picketlink.credential.DefaultLoginCredentials} with them. If the request is not an authentication attempt (as defined by the
     * implementation), then {@code creds} is not affected.
     *
     * @param request
     *            The current request, to examine for authentication information.
     * @param creds
     *            The credentials instance that will be populated with the credentials found in the request, if any.
     */
    void extractCredential(HttpServletRequest request, DefaultLoginCredentials creds);

    /**
     * Challenges the client if no credentials were supplied or the credentials were not extracted in order to continue
     * with the authentication.
     *
     * @param request
     *            The current request, which may be used to obtain a {@link javax.servlet.RequestDispatcher} if needed.
     *            If this method is called, the rest of the filter chain will <i>not</i> be processed, so
     *            implementations are free to read the request body if they so choose.
     * @param response
     *            The current response, which can be used to send HTTP error results, redirects, or for sending
     *            additional challenge headers.
     */
    void challengeClient(HttpServletRequest request, HttpServletResponse response);

    /**
     * Performs any post-authentication logic regarding of the authentication result.
     *
     * @param request
     *            The current request, which may be used to obtain a {@link javax.servlet.RequestDispatcher} if needed.
     * @param response
     *            The current response, which can be used to send an HTTP response, or a redirect.
     * @return true if the processing of the filter chain should continue, false if the processing should stop
     *         (typically because this filter has already sent a response).
     */
    void onPostAuthentication(HttpServletRequest request, HttpServletResponse response);
}