/*
    * 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.assertFalse;
  import static org.junit.jupiter.api.Assertions.assertNotNull;
  import static org.junit.jupiter.api.Assertions.assertNull;
  import static org.junit.jupiter.api.Assertions.assertTrue;
  
  import java.io.ByteArrayInputStream;
  import java.io.IOException;
  import java.time.Duration;
  import java.time.Instant;
  
  import org.apache.commons.io.IOUtils;
  import org.apache.commons.io.ThreadUtils;
  import org.junit.jupiter.api.Test;
  
  /**
   * Tests {@link TimestampedObserver}.
   */
  public class TimestampedObserverTest {
  
      @Test
      public void test() throws IOException, InterruptedException {
          final Instant before = Instant.now();
          // Some OS' clock granularity may be high.
          ThreadUtils.sleep(Duration.ofMillis(20));
          final TimestampedObserver timestampedObserver = new TimestampedObserver();
          assertFalse(timestampedObserver.isClosed());
          // Java 8 instant resolution is not great.
          ThreadUtils.sleep(Duration.ofMillis(20));
          // toString() should not blow up before close().
          assertNotNull(timestampedObserver.toString());
          assertTrue(timestampedObserver.getOpenInstant().isAfter(before));
          assertTrue(timestampedObserver.getOpenToNowDuration().toNanos() > 0);
          assertNull(timestampedObserver.getCloseInstant());
          assertFalse(timestampedObserver.isClosed());
          final byte[] buffer = MessageDigestInputStreamTest.generateRandomByteStream(IOUtils.DEFAULT_BUFFER_SIZE);
          try (ObservableInputStream ois = new ObservableInputStream(new ByteArrayInputStream(buffer), timestampedObserver)) {
              assertTrue(timestampedObserver.getOpenInstant().isAfter(before));
              assertTrue(timestampedObserver.getOpenToNowDuration().toNanos() > 0);
              assertFalse(timestampedObserver.isClosed());
          }
          assertTrue(timestampedObserver.isClosed());
          assertTrue(timestampedObserver.getOpenInstant().isAfter(before));
          assertTrue(timestampedObserver.getOpenToNowDuration().toNanos() > 0);
          assertTrue(timestampedObserver.getCloseInstant().isAfter(timestampedObserver.getOpenInstant()));
          assertTrue(timestampedObserver.getOpenToCloseDuration().toNanos() > 0);
          assertNotNull(timestampedObserver.toString());
      }
  
      @Test
      public void testExample() throws IOException {
          final TimestampedObserver timestampedObserver = new TimestampedObserver();
          final byte[] buffer = MessageDigestInputStreamTest
              .generateRandomByteStream(IOUtils.DEFAULT_BUFFER_SIZE);
          try (ObservableInputStream ois = new ObservableInputStream(new ByteArrayInputStream(buffer),
              timestampedObserver)) {
              //
          }
          // System.out.printf("IO duration: %s%n", timestampedObserver);
          // System.out.printf("IO duration: %s%n", timestampedObserver.getOpenToCloseDuration());
      }
  
  }