/**
 * 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.
 */
package org.apache.hadoop.hdfs.server.datanode.web.dtp;

import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.http.HttpResponseStatus;
import io.netty.handler.codec.http2.DefaultHttp2Headers;
import io.netty.handler.codec.http2.Http2ConnectionEncoder;
import io.netty.handler.codec.http2.Http2Exception;
import io.netty.handler.codec.http2.Http2FrameAdapter;
import io.netty.handler.codec.http2.Http2Headers;

import java.nio.charset.StandardCharsets;

class DtpHttp2FrameListener extends Http2FrameAdapter {

  private Http2ConnectionEncoder encoder;

  public void encoder(Http2ConnectionEncoder encoder) {
    this.encoder = encoder;
  }

  @Override
  public void onHeadersRead(ChannelHandlerContext ctx, int streamId,
      Http2Headers headers, int streamDependency, short weight,
      boolean exclusive, int padding, boolean endStream) throws Http2Exception {
    encoder.writeHeaders(ctx, streamId,
      new DefaultHttp2Headers().status(HttpResponseStatus.OK.codeAsText()), 0,
      false, ctx.newPromise());
    encoder.writeData(
      ctx,
      streamId,
      ctx.alloc().buffer()
          .writeBytes("HTTP/2 DTP".getBytes(StandardCharsets.UTF_8)), 0, true,
      ctx.newPromise());
  }
}