/**
 * 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.activemq.transport.tcp;

import javax.net.SocketFactory;
import java.io.IOException;
import java.net.InetAddress;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.Random;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Automatically generated socket.close() calls to simulate network faults
 */
public class SocketTstFactory extends SocketFactory {

   private static final Logger LOG = LoggerFactory.getLogger(SocketTstFactory.class);

   private static final ConcurrentMap<InetAddress, Integer> closeIter = new ConcurrentHashMap<>();

   private class SocketTst {

      private class Bagot implements Runnable {

         private final Thread processus;
         private final Socket socket;
         private final InetAddress address;

         public Bagot(Random rnd, Socket socket, InetAddress address) {
            this.processus = new Thread(this, "Network Faults maker : undefined");
            this.socket = socket;
            this.address = address;
         }

         public void start() {
            this.processus.setName("Network Faults maker : " + this.socket.toString());
            this.processus.start();
         }

         @Override
         public void run() {
            int lastDelayVal;
            Integer lastDelay;
            while (!this.processus.isInterrupted()) {
               if (!this.socket.isClosed()) {
                  try {
                     lastDelay = closeIter.get(this.address);
                     if (lastDelay == null) {
                        lastDelayVal = 0;
                     } else {
                        lastDelayVal = lastDelay.intValue();
                        if (lastDelayVal > 10)
                           lastDelayVal += 20;
                        else
                           lastDelayVal += 1;
                     }

                     lastDelay = Integer.valueOf(lastDelayVal);

                     LOG.info("Trying to close client socket " + socket.toString() + " in " + lastDelayVal + " milliseconds");

                     try {
                        Thread.sleep(lastDelayVal);
                     } catch (InterruptedException e) {
                        this.processus.interrupt();
                        Thread.currentThread().interrupt();
                     } catch (IllegalArgumentException e) {
                     }

                     this.socket.close();
                     closeIter.put(this.address, lastDelay);
                     LOG.info("Client socket " + this.socket.toString() + " is closed.");
                  } catch (IOException e) {
                  }
               }

               this.processus.interrupt();
            }
         }
      }

      private final Bagot bagot;
      private final Socket socket;

      public SocketTst(InetAddress address, int port, Random rnd) throws IOException {
         this.socket = new Socket(address, port);
         bagot = new Bagot(rnd, this.socket, address);
      }

      public SocketTst(InetAddress address,
                       int port,
                       InetAddress localAddr,
                       int localPort,
                       Random rnd) throws IOException {
         this.socket = new Socket(address, port, localAddr, localPort);
         bagot = new Bagot(rnd, this.socket, address);
      }

      public SocketTst(String address, int port, Random rnd) throws UnknownHostException, IOException {
         this.socket = new Socket(address, port);
         bagot = new Bagot(rnd, this.socket, InetAddress.getByName(address));
      }

      public SocketTst(String address, int port, InetAddress localAddr, int localPort, Random rnd) throws IOException {
         this.socket = new Socket(address, port, localAddr, localPort);
         bagot = new Bagot(rnd, this.socket, InetAddress.getByName(address));
      }

      public Socket getSocket() {
         return this.socket;
      }

      public void startBagot() {
         bagot.start();
      }
   }

   private final Random rnd;

   public SocketTstFactory() {
      super();
      LOG.info("Creating a new SocketTstFactory");
      this.rnd = new Random();
   }

   @Override
   public Socket createSocket(InetAddress host, int port) throws IOException {
      SocketTst sockTst;
      sockTst = new SocketTst(host, port, this.rnd);
      sockTst.startBagot();
      return sockTst.getSocket();
   }

   @Override
   public Socket createSocket(InetAddress host, int port, InetAddress localAddress, int localPort) throws IOException {
      SocketTst sockTst;
      sockTst = new SocketTst(host, port, localAddress, localPort, this.rnd);
      sockTst.startBagot();
      return sockTst.getSocket();
   }

   @Override
   public Socket createSocket(String host, int port) throws IOException {
      SocketTst sockTst;
      sockTst = new SocketTst(host, port, this.rnd);
      sockTst.startBagot();
      return sockTst.getSocket();
   }

   @Override
   public Socket createSocket(String host, int port, InetAddress localAddress, int localPort) throws IOException {
      SocketTst sockTst;
      sockTst = new SocketTst(host, port, localAddress, localPort, this.rnd);
      sockTst.startBagot();
      return sockTst.getSocket();
   }

   private final static SocketTstFactory client = new SocketTstFactory();

   public static SocketFactory getDefault() {
      return client;
   }
}
