/*
 * See the NOTICE file distributed with this work for additional
 * information regarding copyright ownership.
 *
 * 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 com.xpn.xwiki.user.impl.xwiki;

import java.text.MessageFormat;

import org.apache.commons.lang.StringUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import com.xpn.xwiki.XWikiContext;
import com.xpn.xwiki.XWikiException;
import com.xpn.xwiki.user.api.XWikiUser;

/**
 * Implements a authentication mechanism which is trusting the App Server authentication. If it fails it falls back to
 * the standard XWiki authentication
 */
public class AppServerTrustedKerberosAuthServiceImpl extends XWikiAuthServiceImpl
{

    private static final Log LOG = LogFactory.getLog(AppServerTrustedKerberosAuthServiceImpl.class);

    /**
     * @see com.xpn.xwiki.user.impl.xwiki.XWikiAuthServiceImpl#checkAuth(com.xpn.xwiki.XWikiContext)
     */
    @Override
    public XWikiUser checkAuth(XWikiContext context) throws XWikiException
    {
        String user = context.getRequest().getRemoteUser();
        
        LOG.debug(MessageFormat.format("Checking auth for remote user {0}", user));
        
        if ((user == null) || user.equals(""))
            return super.checkAuth(context);
        else {
            if (user.contains("\\"))
                if (user.lastIndexOf("\\") + 1 < user.length())
                    user = user.substring(user.lastIndexOf("\\") + 1);
                else {
                    user = "";
                    return super.checkAuth(context);
                }

            if (user.contains("@")) {
                user = StringUtils.substringBeforeLast(user, "@");
            }

            LOG.debug("Launching create user for " + user);

            user = createUser(user, context);

            LOG.debug("Create user done for " + user);

            user = "XWiki." + user;
        }
        context.setUser(user);

        return new XWikiUser(user);
    }

    /**
     * @see com.xpn.xwiki.user.impl.xwiki.XWikiAuthServiceImpl#checkAuth(java.lang.String, java.lang.String,
     *      java.lang.String, com.xpn.xwiki.XWikiContext)
     */
    @Override
    public XWikiUser checkAuth(String username, String password, String rememberme, XWikiContext context)
        throws XWikiException
    {
        
        String user = context.getRequest().getRemoteUser();
        
        LOG.debug(MessageFormat.format("Checking auth for remote user {0}", user));
        
        if ((user == null) || user.equals("")) {
            return super.checkAuth(username, password, rememberme, context);
        } else {
            if (user.contains("\\"))

                user = StringUtils.substringBeforeLast(user, "\\");

            else {
                user = "";
                return super.checkAuth(username, password, rememberme, context);
            }

            if (user.contains("@")) {
                user = StringUtils.substringBeforeLast(user, "@");
            }

            user = createUser(user, context);

            user = "XWiki." + user;
        }
        context.setUser(user);

        return new XWikiUser(user);
    }
    
}