/*
 * RED5 Open Source Media Server - https://github.com/Red5/ Copyright 2006-2016 by respective authors (see below). 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.red5.server.messaging;

import java.io.IOException;
import java.util.List;
import java.util.Map;

/**
 * Input Endpoint for a consumer to connect.
 *
 * @author The Red5 Project
 * @author Steven Gong (steven.gong@gmail.com)
 */
public interface IMessageInput {
    /**
     * Pull message from this input endpoint. Return w/o waiting.
     *
     * @return The pulled message or null if message is not available.
     * @throws IOException
     *             on error
     */
    IMessage pullMessage() throws IOException;

    /**
     * Pull message from this input endpoint. Wait wait milliseconds if message is not available.
     *
     * @param wait
     *            milliseconds to wait when message is not available.
     * @return The pulled message or null if message is not available.
     */
    IMessage pullMessage(long wait);

    /**
     * Connect to a consumer.
     *
     * @param consumer
     *            Consumer
     * @param paramMap
     *            Parameters map
     * @return true when successfully subscribed, false otherwise.
     */
    boolean subscribe(IConsumer consumer, Map<String, Object> paramMap);

    /**
     * Disconnect from a consumer.
     *
     * @param consumer
     *            Consumer to disconnect
     * @return true when successfully unsubscribed, false otherwise.
     */
    boolean unsubscribe(IConsumer consumer);

    /**
     * Getter for consumers list.
     *
     * @return Consumers.
     */
    List<IConsumer> getConsumers();

    /**
     * Send OOB Control Message to all providers on the other side of pipe.
     *
     * @param consumer
     *            The consumer that sends the message
     * @param oobCtrlMsg
     *            Out-of-band control message
     */
    void sendOOBControlMessage(IConsumer consumer, OOBControlMessage oobCtrlMsg);
}
