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 javax.crypto.BadPaddingException;
  import javax.crypto.Cipher;
  import javax.crypto.IllegalBlockSizeException;
  import javax.crypto.ShortBufferException;
  
  import io.aiven.kafka.tieredstorage.AesKeyAwareTest;
  
  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 DecryptionChunkEnumerationTest extends AesKeyAwareTest {
      @Mock
      DetransformChunkEnumeration inner;
  
      @Mock
      Cipher cipher;
  
      Cipher cipherSupplier(final byte[] encryptedChunk) {
          return cipher;
      }
  
      @Test
      void nullInnerEnumeration() {
          assertThatThrownBy(() -> new DecryptionChunkEnumeration(null, 10, this::cipherSupplier))
              .isInstanceOf(NullPointerException.class)
              .hasMessage("inner cannot be null");
      }
  
      @Test
      void zeroIvSize() {
          assertThatThrownBy(() -> new DecryptionChunkEnumeration(inner, 0, this::cipherSupplier))
              .isInstanceOf(IllegalArgumentException.class)
              .hasMessage("ivSize must be positive");
      }
  
      @Test
      void nullCipherSupplier() {
          assertThatThrownBy(() -> new DecryptionChunkEnumeration(inner, ivSize, null))
              .isInstanceOf(NullPointerException.class)
              .hasMessage("cipherSupplier cannot be null");
      }
  
      @Test
      void hasMoreElementsPropagated() {
          final var transform = new DecryptionChunkEnumeration(inner, ivSize, this::cipherSupplier);
          when(inner.hasMoreElements())
              .thenReturn(true)
              .thenReturn(false);
          assertThat(transform.hasMoreElements()).isTrue();
          assertThat(transform.hasMoreElements()).isFalse();
          verify(inner, times(2)).hasMoreElements();
      }
  
      @Test
      void decrypt() throws IllegalBlockSizeException, BadPaddingException, ShortBufferException {
          final byte[] data = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
          final Cipher encryptionCipher = encryptionCipherSupplier();
          final byte[] iv = encryptionCipher.getIV();
          final byte[] encrypted = new byte[iv.length + encryptionCipher.getOutputSize(data.length)];
          System.arraycopy(iv, 0, encrypted, 0, iv.length);
          encryptionCipher.doFinal(data, 0, data.length, encrypted, iv.length);
  
          final var transform = new DecryptionChunkEnumeration(inner, ivSize, AesKeyAwareTest::decryptionCipherSupplier);
          when(inner.nextElement()).thenReturn(encrypted);
          final byte[] decrypted = transform.nextElement();
  
          assertThat(decrypted).isEqualTo(data);
      }
  }
  