content: /*
   * Copyright 2023 Aiven Oy
   *
   * Licensed 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 io.aiven.kafka.tieredstorage.transform;
  
  import java.io.ByteArrayInputStream;
  import java.io.InputStream;
  import java.io.SequenceInputStream;
  import java.util.Enumeration;
  
  /**
   * The detransformation finisher.
   *
   * <p>It converts enumeration of {@code byte[]} into enumeration of {@link InputStream},
   * so that it could be used in {@link SequenceInputStream}.
   */
  public class DetransformFinisher implements Enumeration<InputStream> {
      private final DetransformChunkEnumeration inner;
  
      public DetransformFinisher(final DetransformChunkEnumeration inner) {
          this.inner = inner;
      }
  
      @Override
      public boolean hasMoreElements() {
          return inner.hasMoreElements();
      }
  
      @Override
      public InputStream nextElement() {
          final var chunk = inner.nextElement();
          return new ByteArrayInputStream(chunk);
      }
  
      public InputStream toInputStream() {
          if (inner instanceof BaseDetransformChunkEnumeration) {
              return ((BaseDetransformChunkEnumeration) inner).inputStream;
          }
  
          return new SequenceInputStream(this);
      }
  }
  