/*
    * ====================================================================
    * 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.
   * ====================================================================
   *
   * This software consists of voluntary contributions made by many
   * individuals on behalf of the Apache Software Foundation.  For more
   * information on the Apache Software Foundation, please see
   * <http://www.apache.org/>.
   *
   */
  package org.apache.hc.core5.http2.impl.nio;
  
  import java.io.IOException;
  import java.nio.ByteBuffer;
  import java.util.List;
  
  import org.apache.hc.core5.annotation.Internal;
  import org.apache.hc.core5.http.Header;
  import org.apache.hc.core5.http.HttpException;
  import org.apache.hc.core5.http.RequestHeaderFieldsTooLargeException;
  import org.apache.hc.core5.http.config.CharCodingConfig;
  import org.apache.hc.core5.http.impl.BasicHttpConnectionMetrics;
  import org.apache.hc.core5.http.nio.AsyncPushConsumer;
  import org.apache.hc.core5.http.nio.AsyncServerExchangeHandler;
  import org.apache.hc.core5.http.nio.HandlerFactory;
  import org.apache.hc.core5.http.nio.command.ExecutableCommand;
  import org.apache.hc.core5.http.protocol.HttpCoreContext;
  import org.apache.hc.core5.http.protocol.HttpProcessor;
  import org.apache.hc.core5.http2.H2ConnectionException;
  import org.apache.hc.core5.http2.H2Error;
  import org.apache.hc.core5.http2.config.H2Config;
  import org.apache.hc.core5.http2.frame.DefaultFrameFactory;
  import org.apache.hc.core5.http2.frame.FrameFactory;
  import org.apache.hc.core5.http2.frame.StreamIdGenerator;
  import org.apache.hc.core5.http2.hpack.HeaderListConstraintException;
  import org.apache.hc.core5.reactor.ProtocolIOSession;
  import org.apache.hc.core5.util.Args;
  
  /**
   * I/O event handler for events fired by {@link ProtocolIOSession} that implements
   * server side HTTP/2 messaging protocol with full support for
   * multiplexed message transmission.
   *
   * @since 5.0
   */
  @Internal
  public class ServerH2StreamMultiplexer extends AbstractH2StreamMultiplexer {
  
      private final HandlerFactory<AsyncServerExchangeHandler> exchangeHandlerFactory;
  
      public ServerH2StreamMultiplexer(
              final ProtocolIOSession ioSession,
              final FrameFactory frameFactory,
              final HttpProcessor httpProcessor,
              final HandlerFactory<AsyncServerExchangeHandler> exchangeHandlerFactory,
              final CharCodingConfig charCodingConfig,
              final H2Config h2Config,
              final H2StreamListener streamListener) {
          super(ioSession, frameFactory, StreamIdGenerator.EVEN, httpProcessor, charCodingConfig, h2Config, streamListener);
          this.exchangeHandlerFactory = Args.notNull(exchangeHandlerFactory, "Handler factory");
      }
  
      public ServerH2StreamMultiplexer(
              final ProtocolIOSession ioSession,
              final HttpProcessor httpProcessor,
              final HandlerFactory<AsyncServerExchangeHandler> exchangeHandlerFactory,
              final CharCodingConfig charCodingConfig,
              final H2Config h2Config) {
          this(ioSession, DefaultFrameFactory.INSTANCE, httpProcessor, exchangeHandlerFactory, charCodingConfig, h2Config, null);
      }
  
      @Override
      void acceptHeaderFrame() throws H2ConnectionException {
      }
  
      @Override
      void acceptPushRequest() throws H2ConnectionException {
      }
  
      @Override
      void acceptPushFrame() throws H2ConnectionException {
          throw new H2ConnectionException(H2Error.PROTOCOL_ERROR, "Push not supported");
      }
 
     @Override
     H2StreamHandler createRemotelyInitiatedStream(
             final H2StreamChannel channel,
             final HttpProcessor httpProcessor,
             final BasicHttpConnectionMetrics connMetrics,
             final HandlerFactory<AsyncPushConsumer> pushHandlerFactory) throws IOException {
         final HttpCoreContext context = HttpCoreContext.create();
         context.setAttribute(HttpCoreContext.SSL_SESSION, getSSLSession());
         context.setAttribute(HttpCoreContext.CONNECTION_ENDPOINT, getEndpointDetails());
         return new ServerH2StreamHandler(channel, httpProcessor, connMetrics, exchangeHandlerFactory, context);
     }
 
     @Override
     H2StreamHandler createLocallyInitiatedStream(
             final ExecutableCommand command,
             final H2StreamChannel channel,
             final HttpProcessor httpProcessor,
             final BasicHttpConnectionMetrics connMetrics) throws IOException {
         throw new H2ConnectionException(H2Error.INTERNAL_ERROR, "Illegal attempt to execute a request");
     }
 
     @Override
     List<Header> decodeHeaders(final ByteBuffer payload) throws HttpException {
         try {
             return super.decodeHeaders(payload);
         } catch (final HeaderListConstraintException ex) {
             throw new RequestHeaderFieldsTooLargeException(ex.getMessage(), ex);
         }
     }
 
     @Override
     public String toString() {
         final StringBuilder buf = new StringBuilder();
         buf.append("[");
         appendState(buf);
         buf.append("]");
         return buf.toString();
     }
 
 }