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.nio.charset.StandardCharsets;
  
  import org.junit.jupiter.api.Test;
  
  import static org.assertj.core.api.Assertions.assertThat;
  
  class DetransformFinisherTest {
  
      @Test
      void sameInputStreamFromBaseDetransform() {
          final byte[] bytes = "test".getBytes(StandardCharsets.UTF_8);
          final var is = new ByteArrayInputStream(bytes);
          final DetransformChunkEnumeration d = new BaseDetransformChunkEnumeration(is);
          final DetransformFinisher f = new DetransformFinisher(d);
          assertThat(f.toInputStream())
              .isEqualTo(is)
              .hasBinaryContent(bytes);
      }
  
      @Test
      void inputStreamMutatesWhenChainedDetransform() {
          final byte[] bytes = "test".getBytes(StandardCharsets.UTF_8);
          final var is = new ByteArrayInputStream(bytes);
          final DetransformChunkEnumeration d = new BaseDetransformChunkEnumeration(is);
          final DetransformChunkEnumeration noop = new NoopDetransformEnumeration(d);
          final DetransformFinisher f = new DetransformFinisher(noop);
          assertThat(f.toInputStream())
              .isNotEqualTo(is)
              .hasBinaryContent(bytes);
      }
  
      private static class NoopDetransformEnumeration implements DetransformChunkEnumeration {
          private final DetransformChunkEnumeration inner;
  
          public NoopDetransformEnumeration(final DetransformChunkEnumeration inner) {
              this.inner = inner;
          }
  
          @Override
          public boolean hasMoreElements() {
              return inner.hasMoreElements();
          }
  
          @Override
          public byte[] nextElement() {
              return inner.nextElement();
          }
      }
  }
  