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 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 EncryptionChunkEnumerationTest extends AesKeyAwareTest {
      @Mock
      TransformChunkEnumeration inner;
  
      @Mock
      Cipher cipher;
  
      Cipher cipherSupplier() {
          return cipher;
      }
  
      @Test
      void nullInnerEnumeration() {
          assertThatThrownBy(() -> new EncryptionChunkEnumeration(null, this::cipherSupplier))
              .isInstanceOf(NullPointerException.class)
              .hasMessage("inner cannot be null");
      }
  
      @Test
      void nullCipherSupplier() {
          assertThatThrownBy(() -> new EncryptionChunkEnumeration(inner, null))
              .isInstanceOf(NullPointerException.class)
              .hasMessage("cipherSupplier cannot be null");
      }
  
      @Test
      void originalChunkSizePropagated() {
          when(inner.originalChunkSize()).thenReturn(100);
          when(cipher.getIV()).thenReturn(new byte[ivSize]);
          final var transform = new EncryptionChunkEnumeration(inner, this::cipherSupplier);
          assertThat(transform.originalChunkSize()).isEqualTo(100);
          verify(inner).originalChunkSize();
      }
  
      @Test
      void transformedChunkSizeIsPropagatedWhenNull() {
          when(inner.transformedChunkSize()).thenReturn(null);
          final var transform = new EncryptionChunkEnumeration(inner, this::cipherSupplier);
          assertThat(transform.transformedChunkSize()).isNull();
          verify(inner).transformedChunkSize();
      }
  
      @Test
      void transformedChunkSizeIsCalculatedWhenNotNull() {
          when(inner.transformedChunkSize()).thenReturn(100);
          when(cipher.getIV()).thenReturn(new byte[ivSize]);
          when(cipher.getOutputSize(100)).thenReturn(100);
          final var transform = new EncryptionChunkEnumeration(inner, this::cipherSupplier);
          assertThat(transform.transformedChunkSize()).isEqualTo(100 + ivSize);
      }
  
      @Test
      void hasMoreElementsPropagated() {
          when(inner.transformedChunkSize()).thenReturn(null);
          final var transform = new EncryptionChunkEnumeration(inner, this::cipherSupplier);
          when(inner.hasMoreElements())
              .thenReturn(true)
              .thenReturn(false);
          assertThat(transform.hasMoreElements()).isTrue();
          assertThat(transform.hasMoreElements()).isFalse();
          verify(inner, times(2)).hasMoreElements();
      }
  
      @Test
      void encrypt() throws IllegalBlockSizeException, BadPaddingException {
          final byte[] data = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
  
          final var transform = new EncryptionChunkEnumeration(inner, AesKeyAwareTest::encryptionCipherSupplier);
          when(inner.nextElement()).thenReturn(data);
          final byte[] encrypted = transform.nextElement();
  
          final Cipher decryptCipher = decryptionCipherSupplier(encrypted);
          assertThat(decryptCipher.doFinal(encrypted, ivSize, encrypted.length - ivSize)).isEqualTo(data);
      }
  }
  