/*
 * Copyright (C) 2005-2008 Jive Software. All rights reserved.
 *
 * 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.jivesoftware.openfire.pubsub.models;

import org.jivesoftware.openfire.pubsub.Node;
import org.xmpp.packet.JID;

/**
 * Policy that defines who is allowed to publish items to the node.
 *
 * @author Matt Tucker
 */
public abstract class PublisherModel {

    public final static PublisherModel open = new OpenPublisher();
    public final static PublisherModel publishers = new OnlyPublishers();
    public final static PublisherModel subscribers = new OnlySubscribers();

    /**
     * Returns the specific subclass of PublisherModel as specified by the publisher
     * model name. If an unknown name is specified then an IllegalArgumentException
     * is going to be thrown.
     *
     * @param name the name of the subsclass.
     * @return the specific subclass of PublisherModel as specified by the access
     *         model name.
     */
    public static PublisherModel valueOf(String name) {
        if ("open".equals(name)) {
            return open;
        }
        else if ("publishers".equals(name)) {
            return publishers;
        }
        else if ("subscribers".equals(name)) {
            return subscribers;
        }
        throw new IllegalArgumentException("Unknown publisher model: " + name);
    }
    /**
     * Returns the name as defined by the JEP-60 spec.
     *
     * @return the name as defined by the JEP-60 spec.
     */
    public abstract String getName();

    /**
     * Returns true if the entity is allowed to publish items to the specified node.
     *
     * @param node       the node that may get a new published item by the specified entity.
     * @param entity     the JID of the entity that wants to publish an item to the node.
     * @return true if the subscriber is allowed to publish items to the specified node.
     */
    public abstract boolean canPublish(Node node, JID entity);

}