package io.netty.handler.codec.http;

import io.netty.bootstrap.ServerBootstrap;
import io.netty.buffer.Unpooled;
import io.netty.channel.*;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioServerSocketChannel;

import java.io.IOException;
import java.net.URL;
import java.net.URLConnection;
import java.util.concurrent.TimeUnit;

import static io.netty.handler.codec.http.HttpHeaderNames.*;
import static io.netty.handler.codec.http.HttpResponseStatus.OK;
import static io.netty.handler.codec.http.HttpVersion.HTTP_1_1;

public class SlowShutdownTest {

  private static final byte[] CONTENT = {'H', 'e', 'l', 'l', 'o', ' ', 'W', 'o', 'r', 'l', 'd'};

  public static void main(String... args) throws InterruptedException, IOException {
    NioEventLoopGroup loop = new NioEventLoopGroup(1);
    ServerBootstrap b = new ServerBootstrap();
    b.group(loop)
      .channel(NioServerSocketChannel.class)
      .childHandler(new ChannelInitializer<SocketChannel>() {
        @Override
        protected void initChannel(SocketChannel ch) throws Exception {
          ch.pipeline()
            .addLast(new HttpServerCodec())
            .addLast(new SimpleChannelInboundHandler<HttpRequest>() {
              @Override
              public void channelReadComplete(ChannelHandlerContext ctx) {
                ctx.flush();
              }

              @Override
              public void channelRead0(ChannelHandlerContext ctx, HttpRequest req) {
                boolean keepAlive = HttpUtil.isKeepAlive(req);
                FullHttpResponse response = new DefaultFullHttpResponse(HTTP_1_1, OK, Unpooled.wrappedBuffer(CONTENT));
                response.headers().set(CONTENT_TYPE, "text/plain");
                response.headers().setInt(CONTENT_LENGTH, response.content().readableBytes());

                if (!keepAlive) {
                  ctx.write(response).addListener(ChannelFutureListener.CLOSE);
                } else {
                  response.headers().set(CONNECTION, HttpHeaderValues.KEEP_ALIVE);
                  ctx.write(response);
                }
              }
            });

        }
      });

    Channel channel = b.bind(8080).sync().channel();
    URLConnection urlConnection = new URL("http://localhost:8080").openConnection();
    urlConnection.connect();
    urlConnection.getInputStream().close();

    channel.close().sync();
    loop.shutdownGracefully(0, 1, TimeUnit.MINUTES);

    long start = System.currentTimeMillis();
    loop.awaitTermination(1, TimeUnit.MINUTES);
    long stop = System.currentTimeMillis();

    System.out.println("Termination took millis: " + (stop - start));
  }
}

if (isShuttingDown()) {
  break;
}