/*
    * 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.omid.tso.client;
  
  import org.apache.phoenix.thirdparty.com.google.common.util.concurrent.SettableFuture;
  import org.apache.phoenix.thirdparty.com.google.common.util.concurrent.ThreadFactoryBuilder;
  import org.apache.omid.proto.TSOProto;
  import org.apache.omid.proto.TSOProto.Response;
  import org.jboss.netty.bootstrap.ClientBootstrap;
  import org.jboss.netty.channel.Channel;
  import org.jboss.netty.channel.ChannelFactory;
  import org.jboss.netty.channel.ChannelFuture;
  import org.jboss.netty.channel.ChannelHandlerContext;
  import org.jboss.netty.channel.ChannelPipeline;
  import org.jboss.netty.channel.ChannelStateEvent;
  import org.jboss.netty.channel.ExceptionEvent;
  import org.jboss.netty.channel.MessageEvent;
  import org.jboss.netty.channel.SimpleChannelHandler;
  import org.jboss.netty.channel.socket.nio.NioClientSocketChannelFactory;
  import org.jboss.netty.handler.codec.frame.LengthFieldBasedFrameDecoder;
  import org.jboss.netty.handler.codec.frame.LengthFieldPrepender;
  import org.jboss.netty.handler.codec.protobuf.ProtobufDecoder;
  import org.jboss.netty.handler.codec.protobuf.ProtobufEncoder;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.net.InetSocketAddress;
  import java.util.concurrent.ArrayBlockingQueue;
  import java.util.concurrent.BlockingQueue;
  import java.util.concurrent.ExecutionException;
  import java.util.concurrent.Executors;
  import java.util.concurrent.Future;
  
  /**
   * Raw client for communicating with tso server directly with protobuf messages
   */
  public class TSOClientRaw {
  
      private static final Logger LOG = LoggerFactory.getLogger(TSOClientRaw.class);
  
      private final BlockingQueue<SettableFuture<Response>> responseQueue
              = new ArrayBlockingQueue<SettableFuture<Response>>(5);
      private final Channel channel;
  
      public TSOClientRaw(String host, int port) throws InterruptedException, ExecutionException {
          // Start client with Nb of active threads = 3 as maximum.
          ChannelFactory factory = new NioClientSocketChannelFactory(
                  Executors.newCachedThreadPool(
                          new ThreadFactoryBuilder().setNameFormat("tsoclient-boss-%d").build()),
                  Executors.newCachedThreadPool(
                          new ThreadFactoryBuilder().setNameFormat("tsoclient-worker-%d").build()), 3);
          // Create the bootstrap
          ClientBootstrap bootstrap = new ClientBootstrap(factory);
  
          InetSocketAddress addr = new InetSocketAddress(host, port);
  
          ChannelPipeline pipeline = bootstrap.getPipeline();
          pipeline.addLast("lengthbaseddecoder",
                  new LengthFieldBasedFrameDecoder(8 * 1024, 0, 4, 0, 4));
          pipeline.addLast("lengthprepender", new LengthFieldPrepender(4));
          pipeline.addLast("protobufdecoder",
                  new ProtobufDecoder(TSOProto.Response.getDefaultInstance()));
          pipeline.addLast("protobufencoder", new ProtobufEncoder());
  
          Handler handler = new Handler();
          pipeline.addLast("handler", handler);
  
          bootstrap.setOption("tcpNoDelay", true);
          bootstrap.setOption("keepAlive", true);
          bootstrap.setOption("reuseAddress", true);
          bootstrap.setOption("connectTimeoutMillis", 100);
  
          ChannelFuture channelFuture = bootstrap.connect(addr).await();
          channel = channelFuture.getChannel();
      }
  
      public void write(TSOProto.Request request) {
          channel.write(request);
      }
  
      public Future<Response> getResponse() throws InterruptedException {
          SettableFuture<Response> future = SettableFuture.create();
          responseQueue.put(future);
          return future;
     }
 
     public void close() throws InterruptedException {
         responseQueue.put(SettableFuture.<Response>create());
         channel.close();
     }
 
     private class Handler extends SimpleChannelHandler {
         @Override
         public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) {
             LOG.info("Message received", e);
             if (e.getMessage() instanceof Response) {
                 Response resp = (Response) e.getMessage();
                 try {
                     SettableFuture<Response> future = responseQueue.take();
                     future.set(resp);
                 } catch (InterruptedException ie) {
                     Thread.currentThread().interrupt();
                     LOG.warn("Interrupted in handler", ie);
                 }
             } else {
                 LOG.warn("Received unknown message", e.getMessage());
             }
         }
 
         @Override
         public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) {
             LOG.info("Exception received", e.getCause());
             try {
                 SettableFuture<Response> future = responseQueue.take();
                 future.setException(e.getCause());
             } catch (InterruptedException ie) {
                 Thread.currentThread().interrupt();
                 LOG.warn("Interrupted handling exception", ie);
             }
         }
 
         @Override
         public void channelDisconnected(ChannelHandlerContext ctx, ChannelStateEvent e)
                 throws Exception {
             LOG.info("Disconnected");
             try {
                 SettableFuture<Response> future = responseQueue.take();
                 future.setException(new ConnectionException());
             } catch (InterruptedException ie) {
                 Thread.currentThread().interrupt();
                 LOG.warn("Interrupted handling exception", ie);
             }
         }
     }
 }