/*
    *  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.mina.transport;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertFalse;
  import static org.junit.Assert.assertNotNull;
  import static org.junit.Assert.assertNull;
  import static org.junit.Assert.assertTrue;
  import static org.junit.Assert.fail;
  
  import java.io.IOException;
  import java.net.SocketAddress;
  import java.util.Collection;
  
  import org.apache.mina.core.buffer.IoBuffer;
  import org.apache.mina.core.future.ConnectFuture;
  import org.apache.mina.core.service.IoAcceptor;
  import org.apache.mina.core.service.IoConnector;
  import org.apache.mina.core.service.IoHandlerAdapter;
  import org.apache.mina.core.session.IdleStatus;
  import org.apache.mina.core.session.IoSession;
  import org.apache.mina.transport.socket.DatagramAcceptor;
  import org.apache.mina.transport.socket.DatagramSessionConfig;
  import org.apache.mina.transport.socket.SocketAcceptor;
  import org.apache.mina.transport.socket.SocketSessionConfig;
  import org.apache.mina.util.AvailablePortFinder;
  import org.junit.After;
  import org.junit.Ignore;
  import org.junit.Test;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * Tests {@link IoAcceptor} resource leakage by repeating bind and unbind.
   *
   * @author <a href="http://mina.apache.org">Apache MINA Project</a>
   */
  public abstract class AbstractBindTest {
      protected final IoAcceptor acceptor;
  
      protected int port;
  
      public AbstractBindTest(IoAcceptor acceptor) {
          this.acceptor = acceptor;
      }
  
      protected abstract SocketAddress createSocketAddress(int port);
  
      protected abstract int getPort(SocketAddress address);
  
      protected abstract IoConnector newConnector();
  
      protected void bind(boolean reuseAddress) throws IOException {
          acceptor.setHandler(new EchoProtocolHandler());
  
          setReuseAddress(reuseAddress);
  
          // Find an available test port and bind to it.
          boolean socketBound = false;
  
          // Let's start from port #1 to detect possible resource leak
          // because test will fail in port 1-1023 if user run this test
          // as a normal user.
          port = AvailablePortFinder.getNextAvailable();
          socketBound = false;
          try {
              acceptor.setDefaultLocalAddress(createSocketAddress(port));
              acceptor.bind();
              socketBound = true;
          } catch (IOException e) {
              //System.out.println(e.getMessage());
          }
  
          // If there is no port available, test fails.
          if (!socketBound) {
              throw new IOException("Cannot bind any test port.");
          }
  
          //System.out.println( "Using port " + port + " for testing." );
      }
  
     private void setReuseAddress(boolean reuseAddress) {
         if (acceptor instanceof DatagramAcceptor) {
             ((DatagramSessionConfig) acceptor.getSessionConfig()).setReuseAddress(reuseAddress);
         } else if (acceptor instanceof SocketAcceptor) {
             ((SocketAcceptor) acceptor).setReuseAddress(reuseAddress);
         }
     }
 
     @After
     public void tearDown() {
         try {
             acceptor.dispose();
         } catch (Exception e) {
             // ignore
         }
 
         acceptor.setDefaultLocalAddress(null);
     }
 
     @Test
     public void testAnonymousBind() throws Exception {
         acceptor.setHandler(new IoHandlerAdapter());
         acceptor.setDefaultLocalAddress(null);
         acceptor.bind();
         assertNotNull(acceptor.getLocalAddress());
         acceptor.unbind(acceptor.getLocalAddress());
         assertNull(acceptor.getLocalAddress());
         acceptor.setDefaultLocalAddress(createSocketAddress(0));
         acceptor.bind();
         assertNotNull(acceptor.getLocalAddress());
         assertTrue(getPort(acceptor.getLocalAddress()) != 0);
         acceptor.unbind(acceptor.getLocalAddress());
     }
 
     @Test
     public void testDuplicateBind() throws IOException {
         bind(false);
 
         try {
             acceptor.bind();
             fail("Exception is not thrown");
         } catch (Exception e) {
             // Signifies a successfull test case execution
             assertTrue(true);
         }
     }
 
     @Test
     public void testDuplicateUnbind() throws IOException {
         bind(false);
 
         // this should succeed
         acceptor.unbind();
 
         // this shouldn't fail
         acceptor.unbind();
     }
 
     @Test
     public void testManyTimes() throws IOException {
         bind(true);
 
         for (int i = 0; i < 1024; i++) {
             acceptor.unbind();
             acceptor.bind();
         }
     }
 
     @Test
     public void testUnbindDisconnectsClients() throws Exception {
         bind(true);
         IoConnector connector = newConnector();
         IoSession[] sessions = new IoSession[5];
         connector.setHandler(new IoHandlerAdapter());
         for (int i = 0; i < sessions.length; i++) {
             ConnectFuture future = connector.connect(createSocketAddress(port));
             future.awaitUninterruptibly();
             sessions[i] = future.getSession();
             assertTrue(sessions[i].isConnected());
             assertTrue(sessions[i].write(IoBuffer.allocate(1)).awaitUninterruptibly().isWritten());
         }
 
         // Wait for the server side sessions to be created.
         Thread.sleep(500);
 
         Collection<IoSession> managedSessions = acceptor.getManagedSessions().values();
         assertEquals(5, managedSessions.size());
 
         acceptor.unbind();
 
         // Wait for the client side sessions to close.
         Thread.sleep(500);
 
         assertEquals(0, managedSessions.size());
         for (IoSession element : managedSessions) {
             assertFalse(element.isConnected());
         }
     }
 
     @Test
     public void testUnbindResume() throws Exception {
         bind(true);
         IoConnector connector = newConnector();
         IoSession session = null;
         connector.setHandler(new IoHandlerAdapter());
 
         ConnectFuture future = connector.connect(createSocketAddress(port));
         future.awaitUninterruptibly();
         session = future.getSession();
         assertTrue(session.isConnected());
         assertTrue(session.write(IoBuffer.allocate(1)).awaitUninterruptibly().isWritten());
 
         // Wait for the server side session to be created.
         Thread.sleep(500);
 
         Collection<IoSession> managedSession = acceptor.getManagedSessions().values();
         assertEquals(1, managedSession.size());
 
         acceptor.unbind();
 
         // Wait for the client side sessions to close.
         Thread.sleep(500);
 
         assertEquals(0, managedSession.size());
         for (IoSession element : managedSession) {
             assertFalse(element.isConnected());
         }
 
         // Rebind
         bind(true);
 
         // Check again the connection
         future = connector.connect(createSocketAddress(port));
         future.awaitUninterruptibly();
         session = future.getSession();
         assertTrue(session.isConnected());
         assertTrue(session.write(IoBuffer.allocate(1)).awaitUninterruptibly().isWritten());
 
         // Wait for the server side session to be created.
         Thread.sleep(500);
 
         managedSession = acceptor.getManagedSessions().values();
         assertEquals(1, managedSession.size());
     }
 
     @Test
     @Ignore
     public void testRegressively() throws IOException {
         setReuseAddress(true);
 
         SocketAddress addr = createSocketAddress(port);
         EchoProtocolHandler handler = new EchoProtocolHandler();
         acceptor.setDefaultLocalAddress(addr);
         acceptor.setHandler(handler);
         for (int i = 0; i < 1048576; i++) {
             acceptor.bind();
             acceptor.unbind();
         }
         bind(false);
     }
 
     private static class EchoProtocolHandler extends IoHandlerAdapter {
         private static final Logger LOG = LoggerFactory.getLogger(EchoProtocolHandler.class);
 
         /**
          * Default constructor
          */
         public EchoProtocolHandler() {
             super();
         }
 
         @Override
         public void sessionCreated(IoSession session) {
             if (session.getConfig() instanceof SocketSessionConfig) {
                 ((SocketSessionConfig) session.getConfig()).setReceiveBufferSize(2048);
             }
 
             session.getConfig().setIdleTime(IdleStatus.BOTH_IDLE, 10);
         }
 
         @Override
         public void sessionIdle(IoSession session, IdleStatus status) {
             LOG.info("*** IDLE #" + session.getIdleCount(IdleStatus.BOTH_IDLE) + " ***");
         }
 
         @Override
         public void exceptionCaught(IoSession session, Throwable cause) {
             //cause.printStackTrace();
             session.closeNow();
         }
 
         @Override
         public void messageReceived(IoSession session, Object message) throws Exception {
             if (!(message instanceof IoBuffer)) {
                 return;
             }
 
             IoBuffer rb = (IoBuffer) message;
             // Write the received data back to remote peer
             IoBuffer wb = IoBuffer.allocate(rb.remaining());
             wb.put(rb);
             wb.flip();
             session.write(wb);
         }
     }
 }