/*
    * 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.netty5.handler.codec.http;
  
  import io.netty5.buffer.api.Buffer;
  import io.netty5.buffer.api.BufferAllocator;
  import io.netty5.util.Send;
  import io.netty5.handler.codec.DecoderResult;
  
  import java.util.Objects;
  
  public final class EmptyLastHttpContent implements LastHttpContent<EmptyLastHttpContent> {
      private final Buffer payload;
      private final BufferAllocator allocator;
  
      public EmptyLastHttpContent(BufferAllocator allocator) {
          payload = allocator.allocate(0);
          this.allocator = allocator;
      }
  
      @Override
      public Buffer payload() {
          return payload;
      }
  
      @Override
      public EmptyLastHttpContent copy() {
          return new EmptyLastHttpContent(allocator);
      }
  
      @Override
      public Send<EmptyLastHttpContent> send() {
          return Send.sending(EmptyLastHttpContent.class, () -> new EmptyLastHttpContent(allocator));
      }
  
      @Override
      public void close() {
          payload.close();
      }
  
      @Override
      public boolean isAccessible() {
          return payload.isAccessible();
      }
  
      @Override
      public EmptyLastHttpContent touch(Object hint) {
          payload.touch(hint);
          return this;
      }
  
      @Override
      public HttpHeaders trailingHeaders() {
          return EmptyHttpHeaders.INSTANCE;
      }
  
      @Override
      public DecoderResult decoderResult() {
          return DecoderResult.success();
      }
  
      @Override
      public void setDecoderResult(DecoderResult result) {
          throw new UnsupportedOperationException("read only");
      }
  
      @Override
      public String toString() {
          return "EmptyLastHttpContent";
      }
  
      @Override
      public boolean equals(Object o) {
          if (this == o) {
              return true;
          }
          if (o == null || getClass() != o.getClass()) {
              return false;
          }
  
          EmptyLastHttpContent that = (EmptyLastHttpContent) o;
  
          return Objects.equals(payload, that.payload) && Objects.equals(allocator, that.allocator);
      }
  
      @Override
      public int hashCode() {
         int result = payload != null ? payload.hashCode() : 0;
         result = 31 * result + (allocator != null ? allocator.hashCode() : 0);
         return result;
     }
 }