/*
    * Copyright 2021 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.http3;
  
  import io.netty.channel.ChannelHandler;
  import io.netty.channel.ChannelHandlerContext;
  import io.netty.handler.codec.http3.Http3FrameCodec.Http3FrameCodecFactory;
  import org.jetbrains.annotations.Nullable;
  
  import java.util.function.LongFunction;
  import java.util.function.Supplier;
  
  final class Http3UnidirectionalStreamInboundClientHandler extends Http3UnidirectionalStreamInboundHandler {
      private final LongFunction<ChannelHandler> pushStreamHandlerFactory;
  
      Http3UnidirectionalStreamInboundClientHandler(
              Http3FrameCodecFactory codecFactory,
              Http3Settings.NonStandardHttp3SettingsValidator nonStandardSettingsValidator,
              Http3ControlStreamInboundHandler localControlStreamHandler,
              Http3ControlStreamOutboundHandler remoteControlStreamHandler,
              @Nullable LongFunction<ChannelHandler> unknownStreamHandlerFactory,
              @Nullable LongFunction<ChannelHandler> pushStreamHandlerFactory,
              Supplier<ChannelHandler> qpackEncoderHandlerFactory, Supplier<ChannelHandler> qpackDecoderHandlerFactory) {
          super(codecFactory, nonStandardSettingsValidator,
                  localControlStreamHandler, remoteControlStreamHandler, unknownStreamHandlerFactory,
                  qpackEncoderHandlerFactory, qpackDecoderHandlerFactory);
          this.pushStreamHandlerFactory = pushStreamHandlerFactory == null ? __ -> ReleaseHandler.INSTANCE :
                  pushStreamHandlerFactory;
      }
  
      @Override
      void initPushStream(ChannelHandlerContext ctx, long pushId) {
          // See https://tools.ietf.org/html/draft-ietf-quic-http-32#section-4.4
          Long maxPushId = remoteControlStreamHandler.sentMaxPushId();
          if (maxPushId == null) {
              Http3CodecUtils.connectionError(ctx, Http3ErrorCode.H3_ID_ERROR,
                      "Received push stream before sending MAX_PUSH_ID frame.", false);
          } else if (maxPushId < pushId) {
              Http3CodecUtils.connectionError(ctx, Http3ErrorCode.H3_ID_ERROR,
                      "Received push stream with ID " + pushId + " greater than the max push ID " + maxPushId
                              + '.', false);
          } else {
              // Replace this handler with the actual push stream handlers.
              final ChannelHandler pushStreamHandler = pushStreamHandlerFactory.apply(pushId);
              ctx.pipeline().replace(this, null, pushStreamHandler);
          }
      }
  }