/*
    * Copyright 2012 The Netty Project
    *
    * The Netty Project 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:
    *
    * https://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 io.netty.testsuite.transport.sctp;
  
  import io.netty.bootstrap.Bootstrap;
  import io.netty.bootstrap.ServerBootstrap;
  import io.netty.buffer.ByteBuf;
  import io.netty.channel.Channel;
  import io.netty.channel.ChannelHandlerContext;
  import io.netty.channel.ChannelInitializer;
  import io.netty.channel.SimpleChannelInboundHandler;
  import io.netty.channel.sctp.SctpChannel;
  import io.netty.handler.codec.sctp.SctpInboundByteStreamHandler;
  import io.netty.handler.codec.sctp.SctpMessageCompletionHandler;
  import io.netty.handler.codec.sctp.SctpOutboundByteStreamHandler;
  import io.netty.testsuite.util.TestUtils;
  import org.junit.jupiter.api.Test;
  
  import java.io.IOException;
  import java.util.Random;
  import java.util.concurrent.atomic.AtomicReference;
  import org.junit.jupiter.api.TestInfo;
  
  import static io.netty.testsuite.transport.TestsuitePermutation.randomBufferType;
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assumptions.assumeTrue;
  
  public class SctpEchoTest extends AbstractSctpTest {
  
      private static final Random random = new Random();
      static final byte[] data = new byte[4096]; //could not test ultra jumbo frames
  
      static {
          random.nextBytes(data);
      }
  
      @Test
      public void testSimpleEcho(TestInfo testInfo) throws Throwable {
          assumeTrue(TestUtils.isSctpSupported());
          run(testInfo, new Runner<ServerBootstrap, Bootstrap>() {
              @Override
              public void run(ServerBootstrap serverBootstrap, Bootstrap bootstrap) throws Throwable {
                  testSimpleEcho(serverBootstrap, bootstrap);
              }
          });
      }
  
      public void testSimpleEcho(ServerBootstrap sb, Bootstrap cb) throws Throwable {
          testSimpleEcho0(sb, cb, false);
      }
  
      @Test
      public void testSimpleEchoUnordered(TestInfo testInfo) throws Throwable {
          assumeTrue(TestUtils.isSctpSupported());
          run(testInfo, new Runner<ServerBootstrap, Bootstrap>() {
              @Override
              public void run(ServerBootstrap serverBootstrap, Bootstrap bootstrap) throws Throwable {
                  testSimpleEchoUnordered(serverBootstrap, bootstrap);
              }
          });
      }
  
      public void testSimpleEchoUnordered(ServerBootstrap sb, Bootstrap cb) throws Throwable {
          testSimpleEcho0(sb, cb, true);
      }
  
      private static void testSimpleEcho0(ServerBootstrap sb, Bootstrap cb, final boolean unordered) throws Throwable {
          final EchoHandler sh = new EchoHandler();
          final EchoHandler ch = new EchoHandler();
  
          sb.childHandler(new ChannelInitializer<SctpChannel>() {
              @Override
              public void initChannel(SctpChannel c) throws Exception {
                  c.pipeline().addLast(
                          new SctpMessageCompletionHandler(),
                          new SctpInboundByteStreamHandler(0, 0),
                          new SctpOutboundByteStreamHandler(0, 0, unordered),
                          sh);
              }
          });
          cb.handler(new ChannelInitializer<SctpChannel>() {
              @Override
              public void initChannel(SctpChannel c) throws Exception {
                  c.pipeline().addLast(
                          new SctpMessageCompletionHandler(),
                          new SctpInboundByteStreamHandler(0, 0),
                         new SctpOutboundByteStreamHandler(0, 0, unordered),
                         ch);
             }
         });
 
         Channel sc = sb.bind().sync().channel();
         Channel cc = cb.connect(sc.localAddress()).sync().channel();
 
         for (int i = 0; i < data.length;) {
             int length = Math.min(random.nextInt(1024 * 64), data.length - i);
             ByteBuf msg = randomBufferType(sc.alloc(), data, i, length);
             cc.writeAndFlush(msg);
             i += length;
         }
 
         while (ch.counter < data.length) {
             if (sh.exception.get() != null) {
                 break;
             }
             if (ch.exception.get() != null) {
                 break;
             }
 
             Thread.sleep(50);
         }
 
         while (sh.counter < data.length) {
             if (sh.exception.get() != null) {
                 break;
             }
             if (ch.exception.get() != null) {
                 break;
             }
 
             Thread.sleep(50);
         }
 
         sh.channel.close().sync();
         ch.channel.close().sync();
         sc.close().sync();
 
         if (sh.exception.get() != null && !(sh.exception.get() instanceof IOException)) {
             throw sh.exception.get();
         }
         if (ch.exception.get() != null && !(ch.exception.get() instanceof IOException)) {
             throw ch.exception.get();
         }
         if (sh.exception.get() != null) {
             throw sh.exception.get();
         }
         if (ch.exception.get() != null) {
             throw ch.exception.get();
         }
     }
 
     private static class EchoHandler extends SimpleChannelInboundHandler<ByteBuf> {
         volatile Channel channel;
         final AtomicReference<Throwable> exception = new AtomicReference<Throwable>();
         volatile int counter;
 
         @Override
         public void channelActive(ChannelHandlerContext ctx) throws Exception {
             channel = ctx.channel();
         }
 
         @Override
         public void channelRead0(ChannelHandlerContext ctx, ByteBuf in) throws Exception {
             byte[] actual = new byte[in.readableBytes()];
             in.readBytes(actual);
 
             int lastIdx = counter;
             for (int i = 0; i < actual.length; i++) {
                 assertEquals(data[i + lastIdx], actual[i]);
             }
 
             // Update the counter before calling write(...) as write could in theory trigger another channelRead(...)
             // which then would use the wrong lastIdx.
             counter += actual.length;
 
             if (channel.parent() != null) {
                 channel.writeAndFlush(randomBufferType(channel.alloc(), actual, 0, actual.length));
             }
         }
 
         @Override
         public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
             if (exception.compareAndSet(null, cause)) {
                 ctx.close();
             }
         }
     }
 }