/*
    * Copyright 2013 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.handler.codec.http.websocketx;
  
  import io.netty.channel.ChannelFuture;
  import io.netty.channel.ChannelFutureListener;
  import io.netty.channel.ChannelHandlerContext;
  import io.netty.channel.ChannelInboundHandlerAdapter;
  import io.netty.channel.ChannelPromise;
  import io.netty.handler.codec.http.FullHttpResponse;
  import io.netty.handler.codec.http.websocketx.WebSocketClientProtocolHandler.ClientHandshakeStateEvent;
  import io.netty.util.concurrent.Future;
  import io.netty.util.concurrent.FutureListener;
  
  import java.util.concurrent.TimeUnit;
  
  import static io.netty.util.internal.ObjectUtil.*;
  
  class WebSocketClientProtocolHandshakeHandler extends ChannelInboundHandlerAdapter {
      private static final long DEFAULT_HANDSHAKE_TIMEOUT_MS = 10000L;
  
      private final WebSocketClientHandshaker handshaker;
      private final long handshakeTimeoutMillis;
      private ChannelHandlerContext ctx;
      private ChannelPromise handshakePromise;
  
      WebSocketClientProtocolHandshakeHandler(WebSocketClientHandshaker handshaker) {
          this(handshaker, DEFAULT_HANDSHAKE_TIMEOUT_MS);
      }
  
      WebSocketClientProtocolHandshakeHandler(WebSocketClientHandshaker handshaker, long handshakeTimeoutMillis) {
          this.handshaker = handshaker;
          this.handshakeTimeoutMillis = checkPositive(handshakeTimeoutMillis, "handshakeTimeoutMillis");
      }
  
      @Override
      public void handlerAdded(ChannelHandlerContext ctx) throws Exception {
          this.ctx = ctx;
          handshakePromise = ctx.newPromise();
      }
  
      @Override
      public void channelActive(final ChannelHandlerContext ctx) throws Exception {
          super.channelActive(ctx);
          handshaker.handshake(ctx.channel()).addListener(new ChannelFutureListener() {
              @Override
              public void operationComplete(ChannelFuture future) throws Exception {
                  if (!future.isSuccess()) {
                      handshakePromise.tryFailure(future.cause());
                      ctx.fireExceptionCaught(future.cause());
                  } else {
                      ctx.fireUserEventTriggered(
                              WebSocketClientProtocolHandler.ClientHandshakeStateEvent.HANDSHAKE_ISSUED);
                  }
              }
          });
          applyHandshakeTimeout();
      }
  
      @Override
      public void channelInactive(ChannelHandlerContext ctx) throws Exception {
          if (!handshakePromise.isDone()) {
              handshakePromise.tryFailure(new WebSocketClientHandshakeException("channel closed with handshake " +
                                                                                "in progress"));
          }
  
          super.channelInactive(ctx);
      }
  
      @Override
      public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
          if (!(msg instanceof FullHttpResponse)) {
              ctx.fireChannelRead(msg);
              return;
          }
  
          FullHttpResponse response = (FullHttpResponse) msg;
          try {
              if (!handshaker.isHandshakeComplete()) {
                  handshaker.finishHandshake(ctx.channel(), response);
                  handshakePromise.trySuccess();
                  ctx.fireUserEventTriggered(
                          WebSocketClientProtocolHandler.ClientHandshakeStateEvent.HANDSHAKE_COMPLETE);
                  ctx.pipeline().remove(this);
                  return;
              }
             throw new IllegalStateException("WebSocketClientHandshaker should have been non finished yet");
         } finally {
             response.release();
         }
     }
 
     private void applyHandshakeTimeout() {
         final ChannelPromise localHandshakePromise = handshakePromise;
         if (handshakeTimeoutMillis <= 0 || localHandshakePromise.isDone()) {
             return;
         }
 
         final Future<?> timeoutFuture = ctx.executor().schedule(new Runnable() {
             @Override
             public void run() {
                 if (localHandshakePromise.isDone()) {
                     return;
                 }
 
                 if (localHandshakePromise.tryFailure(new WebSocketClientHandshakeException("handshake timed out"))) {
                     ctx.flush()
                        .fireUserEventTriggered(ClientHandshakeStateEvent.HANDSHAKE_TIMEOUT)
                        .close();
                 }
             }
         }, handshakeTimeoutMillis, TimeUnit.MILLISECONDS);
 
         // Cancel the handshake timeout when handshake is finished.
         localHandshakePromise.addListener(new FutureListener<Void>() {
             @Override
             public void operationComplete(Future<Void> f) throws Exception {
                 timeoutFuture.cancel(false);
             }
         });
     }
 
     /**
      * This method is visible for testing.
      *
      * @return current handshake future
      */
     ChannelFuture getHandshakeFuture() {
         return handshakePromise;
     }
 }