/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.apache.catalina.authenticator;

import java.io.Serializable;

import org.apache.catalina.Authenticator;
import org.apache.catalina.Context;
import org.apache.catalina.Manager;
import org.apache.catalina.Session;
import org.apache.catalina.SessionEvent;
import org.apache.catalina.SessionListener;

/**
 * Listener that notifies the {@link SingleSignOn} valve when a session is destroyed or its ID changes.
 */
public class SingleSignOnListener implements SessionListener, Serializable {

    private static final long serialVersionUID = 1L;

    /**
     * The SSO identifier associated with this listener.
     */
    private final String ssoId;

    /**
     * Creates a new SSO listener for the given SSO identifier.
     *
     * @param ssoId the SSO identifier associated with this listener
     */
    public SingleSignOnListener(String ssoId) {
        this.ssoId = ssoId;
    }


    @Override
    public void sessionEvent(SessionEvent event) {
        final String type = event.getType();
        if (!(Session.SESSION_DESTROYED_EVENT.equals(type) || Session.SESSION_CHANGED_ID_EVENT.equals(type))) {
            return;
        }

        Session session = event.getSession();
        Manager manager = session.getManager();
        if (manager == null) {
            return;
        }
        Context context = manager.getContext();
        Authenticator authenticator = context.getAuthenticator();
        if (!(authenticator instanceof AuthenticatorBase)) {
            return;
        }
        SingleSignOn sso = ((AuthenticatorBase) authenticator).sso;
        if (sso == null) {
            return;
        }

        switch (type) {
            case Session.SESSION_CHANGED_ID_EVENT:
                sso.sessionChangedId(ssoId, session, (String) event.getData());
                break;

            case Session.SESSION_DESTROYED_EVENT:
                sso.sessionDestroyed(ssoId, session);
                break;
        }
    }
}
