package ca.grimoire.caprox;

import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;

import org.jboss.xnio.ChannelListener;
import org.jboss.xnio.IoUtils;
import org.jboss.xnio.OptionMap;
import org.jboss.xnio.TcpConnector;
import org.jboss.xnio.TcpServer;
import org.jboss.xnio.Xnio;
import org.jboss.xnio.channels.Channels;
import org.jboss.xnio.channels.TcpChannel;

public final class SimpleForwardServer {

	private static final class ForwardListener implements
			ChannelListener<TcpChannel> {
		public ForwardListener(TcpChannel destination) {
			this.destination = destination;
		}

		private final TcpChannel destination;

		public void handleEvent(final TcpChannel channel) {
			final ByteBuffer buffer = ByteBuffer.allocate(512);
			int res;
			try {
				while ((res = channel.read(buffer)) > 0) {
					buffer.flip();
					Channels.writeBlocking(destination, buffer);
				}
				// make sure everything is flushed out
				Channels.flushBlocking(channel);
				if (res == -1) {
					channel.close();
				} else {
					channel.resumeReads();
				}
			} catch (IOException e) {
				e.printStackTrace();
				IoUtils.safeClose(channel);
			}
		}
	}

	public static void main(String[] args) throws Exception {
		final Xnio xnio = Xnio.create();

		// Create an open listener.
		final TcpConnector connector = xnio.createTcpConnector(OptionMap.EMPTY);

		final ChannelListener<TcpChannel> openListener = new ChannelListener<TcpChannel>() {
			public void handleEvent(final TcpChannel clientChannel) {
				final ChannelListener<TcpChannel> connectionCompletedListener = new ChannelListener<TcpChannel>() {
					@Override
					public void handleEvent(TcpChannel serverChannel) {
						serverChannel.getReadSetter().set(
								new ForwardListener(clientChannel));
						serverChannel.resumeReads();

						clientChannel.getReadSetter().set(
								new ForwardListener(serverChannel));
						clientChannel.resumeReads();
					}
				};

				InetSocketAddress dest = new InetSocketAddress("localhost",
						5672);
				connector.connectTo(dest, connectionCompletedListener, null);
			}
		};

		// Create the server.
		final TcpServer server = xnio.createTcpServer(openListener,
				OptionMap.EMPTY);

		// Bind it.
		server.bind(new InetSocketAddress(12345));
	}
}