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 com.github.luben.zstd.Zstd;
  import org.junit.jupiter.api.Test;
  import org.junit.jupiter.api.extension.ExtendWith;
  import org.mockito.Mock;
  import org.mockito.junit.jupiter.MockitoExtension;
  
  import static org.assertj.core.api.Assertions.assertThat;
  import static org.assertj.core.api.Assertions.assertThatThrownBy;
  import static org.mockito.Mockito.times;
  import static org.mockito.Mockito.verify;
  import static org.mockito.Mockito.when;
  
  @ExtendWith(MockitoExtension.class)
  class CompressionChunkEnumerationTest {
      @Mock
      TransformChunkEnumeration inner;
  
      @Test
      void nullInnerEnumeration() {
          assertThatThrownBy(() -> new CompressionChunkEnumeration(null))
              .isInstanceOf(NullPointerException.class)
              .hasMessage("inner cannot be null");
      }
  
      @Test
      void originalChunkSizePropagated() {
          when(inner.originalChunkSize()).thenReturn(123);
          final var transform = new CompressionChunkEnumeration(inner);
          assertThat(transform.originalChunkSize()).isEqualTo(123);
          verify(inner).originalChunkSize();
      }
  
      @Test
      void transformedChunkSize() {
          final var transform = new CompressionChunkEnumeration(inner);
          assertThat(transform.transformedChunkSize()).isNull();
      }
  
      @Test
      void hasMoreElementsPropagated() {
          final var transform = new CompressionChunkEnumeration(inner);
          when(inner.hasMoreElements())
              .thenReturn(true)
              .thenReturn(false);
          assertThat(transform.hasMoreElements()).isTrue();
          assertThat(transform.hasMoreElements()).isFalse();
          verify(inner, times(2)).hasMoreElements();
      }
  
      @Test
      void compress() {
          final byte[] data = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
          final var transform = new CompressionChunkEnumeration(inner);
          when(inner.nextElement()).thenReturn(data);
  
          final byte[] compressed = transform.nextElement();
          final byte[] decompressed = new byte[data.length];
          Zstd.decompress(decompressed, compressed);
          assertThat(decompressed).isEqualTo(data);
      }
  }
  