/*
    * 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.io.input;
  
  import static org.junit.jupiter.api.Assertions.assertArrayEquals;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  
  import java.io.ByteArrayInputStream;
  import java.util.Random;
  
  import org.apache.commons.codec.digest.DigestUtils;
  import org.apache.commons.codec.digest.MessageDigestAlgorithms;
  import org.junit.jupiter.api.Test;
  
  /**
   * Tests {@link MessageDigestInputStream}.
   */
  public class MessageDigestInputStreamTest {
  
      static byte[] generateRandomByteStream(final int pSize) {
          final byte[] buffer = new byte[pSize];
          final Random rnd = new Random();
          rnd.nextBytes(buffer);
          return buffer;
      }
  
      @Test
      public void testNoDefault() throws Exception {
          assertThrows(IllegalStateException.class, () -> MessageDigestInputStream.builder().get());
          assertThrows(NullPointerException.class, () -> MessageDigestInputStream.builder().setInputStream(new ByteArrayInputStream(new byte[] { 1 })).get());
      }
  
      @Test
      public void testNormalUse() throws Exception {
          for (int i = 256; i < 8192; i *= 2) {
              final byte[] buffer = generateRandomByteStream(i);
              final byte[] expect = DigestUtils.sha512(buffer);
              try (MessageDigestInputStream messageDigestInputStream = MessageDigestInputStream.builder().setMessageDigest(MessageDigestAlgorithms.SHA_512)
                      .setInputStream(new ByteArrayInputStream(buffer)).get()) {
                  messageDigestInputStream.consume();
                  assertArrayEquals(expect, messageDigestInputStream.getMessageDigest().digest());
              }
              try (MessageDigestInputStream messageDigestInputStream = MessageDigestInputStream.builder().setByteArray(buffer)
                      .setMessageDigest(DigestUtils.getSha512Digest()).get()) {
                  messageDigestInputStream.consume();
                  assertArrayEquals(expect, messageDigestInputStream.getMessageDigest().digest());
              }
          }
      }
  
  }