/*
    * Licensed to the Apache Software Foundation (ASF) under one or more
    * contributor license agreements.  See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * The ASF licenses this file to You 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 org.apache.commons.compress.utils;
  
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertNotEquals;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  
  import java.io.BufferedInputStream;
  import java.io.ByteArrayInputStream;
  import java.io.IOException;
  import java.util.zip.Adler32;
  import java.util.zip.CRC32;
  import java.util.zip.CheckedInputStream;
  
  import org.junit.jupiter.api.Test;
  
  /**
   * Unit tests for class {@link ChecksumCalculatingInputStream org.apache.commons.compress.utils.ChecksumCalculatingInputStream}.
   *
   * @see ChecksumCalculatingInputStream
   */
  public class ChecksumCalculatingInputStreamTest {
  
      @Test
      public void testClassInstantiationWithParameterBeingNullThrowsNullPointerExceptionOne() {
          assertThrows(NullPointerException.class, () -> new ChecksumCalculatingInputStream(null, null));
      }
  
      @Test
      public void testClassInstantiationWithParameterBeingNullThrowsNullPointerExceptionThree() {
          assertThrows(NullPointerException.class, () -> new ChecksumCalculatingInputStream(new CRC32(), null));
      }
  
      @Test
      public void testClassInstantiationWithParameterBeingNullThrowsNullPointerExceptionTwo() {
          assertThrows(NullPointerException.class, () -> new ChecksumCalculatingInputStream(null, new ByteArrayInputStream(new byte[1])));
      }
  
      @Test
      public void testReadTakingByteArray() throws IOException {
          final Adler32 adler32 = new Adler32();
          final byte[] byteArray = new byte[6];
          final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(byteArray);
          try (ChecksumCalculatingInputStream checksumCalculatingInputStream = new ChecksumCalculatingInputStream(adler32, byteArrayInputStream)) {
              final int readResult = checksumCalculatingInputStream.read(byteArray);
              assertEquals(6, readResult);
              assertEquals(0, byteArrayInputStream.available());
              assertEquals(393217L, checksumCalculatingInputStream.getValue());
          }
      }
  
      @Test
      public void testReadTakingByteArraySanityCheck() throws IOException {
          final Adler32 adler32 = new Adler32();
          final byte[] byteArray = new byte[6];
          final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(byteArray);
          try (CheckedInputStream checksumCalculatingInputStream = new CheckedInputStream(byteArrayInputStream, adler32)) {
              final int readResult = checksumCalculatingInputStream.read(byteArray);
              assertEquals(6, readResult);
              assertEquals(0, byteArrayInputStream.available());
              assertEquals(393217L, checksumCalculatingInputStream.getChecksum().getValue());
          }
      }
  
      @Test
      public void testReadTakingNoArguments() throws IOException {
          final Adler32 adler32 = new Adler32();
          final byte[] byteArray = new byte[6];
          final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(byteArray);
          final ChecksumCalculatingInputStream checksumCalculatingInputStream = new ChecksumCalculatingInputStream(adler32, byteArrayInputStream);
          try (BufferedInputStream bufferedInputStream = new BufferedInputStream(checksumCalculatingInputStream)) {
              final int inputStreamReadResult = bufferedInputStream.read(byteArray, 0, 1);
              final int checkSumCalculationReadResult = checksumCalculatingInputStream.read();
              assertNotEquals(checkSumCalculationReadResult, inputStreamReadResult);
              assertEquals(-1, checkSumCalculationReadResult);
              assertEquals(0, byteArrayInputStream.available());
              assertEquals(393217L, checksumCalculatingInputStream.getValue());
          }
      }
  
      @Test
      public void testReadTakingNoArgumentsSanityCheck() throws IOException {
          final Adler32 adler32 = new Adler32();
          final byte[] byteArray = new byte[6];
         final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(byteArray);
         final CheckedInputStream checksumCalculatingInputStream = new CheckedInputStream(byteArrayInputStream, adler32);
         try (BufferedInputStream bufferedInputStream = new BufferedInputStream(checksumCalculatingInputStream)) {
             final int inputStreamReadResult = bufferedInputStream.read(byteArray, 0, 1);
             final int checkSumCalculationReadResult = checksumCalculatingInputStream.read();
             assertNotEquals(checkSumCalculationReadResult, inputStreamReadResult);
             assertEquals(-1, checkSumCalculationReadResult);
             assertEquals(0, byteArrayInputStream.available());
             assertEquals(393217L, checksumCalculatingInputStream.getChecksum().getValue());
         }
     }
 
     @Test
     public void testSkipReturningPositive() throws IOException {
         final Adler32 adler32 = new Adler32();
         final byte[] byteArray = new byte[6];
         final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(byteArray);
         try (ChecksumCalculatingInputStream checksumCalculatingInputStream = new ChecksumCalculatingInputStream(adler32, byteArrayInputStream)) {
             final long skipResult = checksumCalculatingInputStream.skip((byte) 0);
             assertEquals(0, skipResult);
             assertEquals(1, checksumCalculatingInputStream.getValue());
         }
     }
 
     @Test
     public void testSkipReturningPositiveSanityCheck() throws IOException {
         final Adler32 adler32 = new Adler32();
         final byte[] byteArray = new byte[6];
         final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(byteArray);
         try (CheckedInputStream checksumCalculatingInputStream = new CheckedInputStream(byteArrayInputStream, adler32)) {
             final long skipResult = checksumCalculatingInputStream.skip((byte) 0);
             assertEquals(0, skipResult);
             assertEquals(1, checksumCalculatingInputStream.getChecksum().getValue());
         }
     }
 
     @Test
     public void testSkipReturningZero() throws IOException {
         final Adler32 adler32 = new Adler32();
         final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(ByteUtils.EMPTY_BYTE_ARRAY);
         try (ChecksumCalculatingInputStream checksumCalculatingInputStream = new ChecksumCalculatingInputStream(adler32, byteArrayInputStream)) {
             final long skipResult = checksumCalculatingInputStream.skip(60L);
             assertEquals(0L, skipResult);
             assertEquals(1L, checksumCalculatingInputStream.getValue());
         }
     }
 
     @Test
     public void testSkipReturningZeroSanityCheck() throws IOException {
         final Adler32 adler32 = new Adler32();
         final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(ByteUtils.EMPTY_BYTE_ARRAY);
         try (CheckedInputStream checksumCalculatingInputStream = new CheckedInputStream(byteArrayInputStream, adler32)) {
             final long skipResult = checksumCalculatingInputStream.skip(60L);
             assertEquals(0L, skipResult);
             assertEquals(1L, checksumCalculatingInputStream.getChecksum().getValue());
         }
     }
 
 }