/**
 * 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 com.alibaba.jstorm.message.netty;

import java.net.InetSocketAddress;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.Executors;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.TimeUnit;

import org.jboss.netty.bootstrap.ServerBootstrap;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelFactory;
import org.jboss.netty.channel.group.ChannelGroup;
import org.jboss.netty.channel.group.DefaultChannelGroup;
import org.jboss.netty.channel.socket.nio.NioServerSocketChannelFactory;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import backtype.storm.Config;
import backtype.storm.messaging.IConnection;
import backtype.storm.messaging.TaskMessage;
import backtype.storm.utils.DisruptorQueue;
import backtype.storm.utils.Utils;

import com.alibaba.jstorm.utils.JStormUtils;
import com.alibaba.jstorm.client.ConfigExtension;

class NettyServer implements IConnection {
    private static final Logger LOG = LoggerFactory.getLogger(NettyServer.class);
    @SuppressWarnings("rawtypes")
    Map storm_conf;
    int port;

    // private LinkedBlockingQueue message_queue;
    volatile ChannelGroup allChannels = new DefaultChannelGroup("jstorm-server");
    final ChannelFactory factory;
    final ServerBootstrap bootstrap;

    // ayncBatch is only one solution, so directly set it as true
    private final boolean isSyncMode;

    private ConcurrentHashMap<Integer, DisruptorQueue> deserializeQueues;

    @SuppressWarnings("rawtypes")
    NettyServer(Map storm_conf, int port, boolean isSyncMode, ConcurrentHashMap<Integer, DisruptorQueue> deserializeQueues) {
        this.storm_conf = storm_conf;
        this.port = port;
        this.isSyncMode = isSyncMode;
        this.deserializeQueues = deserializeQueues;

        // Configure the server.
        int buffer_size = Utils.getInt(storm_conf.get(Config.STORM_MESSAGING_NETTY_BUFFER_SIZE));
        int maxWorkers = Utils.getInt(storm_conf.get(Config.STORM_MESSAGING_NETTY_SERVER_WORKER_THREADS));

        // asyncBatch = ConfigExtension.isNettyTransferAsyncBatch(storm_conf);

        ThreadFactory bossFactory = new NettyRenameThreadFactory("server" + "-boss");
        ThreadFactory workerFactory = new NettyRenameThreadFactory("server" + "-worker");
        if (maxWorkers > 0) {
            factory = new NioServerSocketChannelFactory(Executors.newCachedThreadPool(bossFactory), Executors.newCachedThreadPool(workerFactory), maxWorkers);
        } else {
            factory = new NioServerSocketChannelFactory(Executors.newCachedThreadPool(bossFactory), Executors.newCachedThreadPool(workerFactory));
        }

        bootstrap = new ServerBootstrap(factory);
        bootstrap.setOption("reuserAddress", true);
        bootstrap.setOption("child.tcpNoDelay", true);
        bootstrap.setOption("child.receiveBufferSize", buffer_size);
        bootstrap.setOption("child.keepAlive", true);

        // Set up the pipeline factory.
        bootstrap.setPipelineFactory(new StormServerPipelineFactory(this, storm_conf));

        // Bind and start to accept incoming connections.
        Channel channel = bootstrap.bind(new InetSocketAddress(port));
        allChannels.add(channel);

        LOG.info("Successfull bind {}, buffer_size:{}, maxWorkers:{}", port, buffer_size, maxWorkers);
    }

    @Override
    public void registerQueue(Integer taskId, DisruptorQueue recvQueu) {
        deserializeQueues.put(taskId, recvQueu);
    }

    /**
     * enqueue a received message
     * 
     * @param message
     * @throws InterruptedException
     */
    public void enqueue(TaskMessage message) {

        int task = message.task();

        DisruptorQueue queue = deserializeQueues.get(task);
        if (queue == null) {
            LOG.debug("Received invalid message directed at port " + task + ". Dropping...");
            return;
        }

        queue.publish(message.message());
    }

    /**
     * fetch a message from message queue synchronously (flags != 1) or asynchronously (flags==1)
     */
    public Object recv(Integer taskId, int flags) {
        try {
            DisruptorQueue recvQueue = deserializeQueues.get(taskId);
            if ((flags & 0x01) == 0x01) {
                return recvQueue.poll();
                // non-blocking

            } else {
                return recvQueue.take();

            }

        } catch (Exception e) {
            LOG.warn("Occur unexception ", e);
            return null;
        }

    }

    /**
     * register a newly created channel
     * 
     * @param channel
     */
    protected void addChannel(Channel channel) {
        allChannels.add(channel);
    }

    /**
     * close a channel
     * 
     * @param channel
     */
    protected void closeChannel(Channel channel) {
        MessageDecoder.removeTransmitHistogram(channel);
        channel.close().awaitUninterruptibly();
        allChannels.remove(channel);
    }

    /**
     * close all channels, and release resources
     */
    public synchronized void close() {
        LOG.info("Begin to shutdown NettyServer");
        if (allChannels != null) {
            new Thread(new Runnable() {

                @Override
                public void run() {
                    try {
                        // await(5, TimeUnit.SECONDS)
                        // sometimes allChannels.close() will block the exit
                        // thread
                        allChannels.close().await(1, TimeUnit.SECONDS);
                        LOG.info("Successfully close all channel");
                        factory.releaseExternalResources();
                    } catch (Exception e) {

                    }
                    allChannels = null;
                }
            }).start();

            JStormUtils.sleepMs(1 * 1000);
        }
        LOG.info("Successfully shutdown NettyServer");
    }

    @Override
    public void send(List<TaskMessage> messages) {
        throw new UnsupportedOperationException("Server connection should not send any messages");
    }

    @Override
    public void send(TaskMessage message) {
        throw new UnsupportedOperationException("Server connection should not send any messages");
    }

    @Override
    public boolean isClosed() {
        // TODO Auto-generated method stub
        return false;
    }

    public boolean isSyncMode() {
        return isSyncMode;
    }

    @Override
    public boolean available() {
        return true;
    }
}