/*
    * 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.output;
  
  import static java.nio.charset.StandardCharsets.UTF_8;
  import static java.util.concurrent.TimeUnit.SECONDS;
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertNotNull;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  
  import java.io.InterruptedIOException;
  import java.nio.charset.StandardCharsets;
  import java.util.concurrent.Callable;
  import java.util.concurrent.Exchanger;
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.Executors;
  import java.util.concurrent.LinkedBlockingQueue;
  
  import org.apache.commons.io.IOUtils;
  import org.apache.commons.io.input.QueueInputStream;
  import org.apache.commons.io.input.QueueInputStreamTest;
  import org.junit.jupiter.api.AfterAll;
  import org.junit.jupiter.api.Test;
  
  /**
   * Test {@link QueueOutputStream} and {@link QueueInputStream}
   *
   * @see QueueInputStreamTest
   */
  public class QueueOutputStreamTest {
  
      private static final ExecutorService executorService = Executors.newFixedThreadPool(5);
  
      @AfterAll
      public static void afterAll() {
          executorService.shutdown();
      }
  
      private static <T> T callInThrowAwayThread(final Callable<T> callable) throws Exception {
          final Exchanger<T> exchanger = new Exchanger<>();
          executorService.submit(() -> {
              final T value = callable.call();
              exchanger.exchange(value);
              return null;
          });
          return exchanger.exchange(null);
      }
  
      @Test
      public void testNullArgument() {
          assertThrows(NullPointerException.class, () -> new QueueOutputStream(null), "queue is required");
      }
  
      @Test
      public void testWriteInterrupted() throws Exception {
          try (QueueOutputStream outputStream = new QueueOutputStream(new LinkedBlockingQueue<>(1));
                  final QueueInputStream inputStream = outputStream.newQueueInputStream()) {
  
              final int timeout = 1;
              final Exchanger<Thread> writerThreadExchanger = new Exchanger<>();
              final Exchanger<Exception> exceptionExchanger = new Exchanger<>();
              executorService.submit(() -> {
                  final Thread writerThread = writerThreadExchanger.exchange(null, timeout, SECONDS);
                  writerThread.interrupt();
                  return null;
              });
  
              executorService.submit(() -> {
                  try {
                      writerThreadExchanger.exchange(Thread.currentThread(), timeout, SECONDS);
                      outputStream.write("ABC".getBytes(StandardCharsets.UTF_8));
                  } catch (final Exception e) {
                      Thread.interrupted(); //clear interrupt
                      exceptionExchanger.exchange(e, timeout, SECONDS);
                  }
                  return null;
              });
  
              final Exception exception = exceptionExchanger.exchange(null, timeout, SECONDS);
              assertNotNull(exception);
              assertEquals(exception.getClass(), InterruptedIOException.class);
          }
      }
  
      @Test
     public void testWriteString() throws Exception {
         try (QueueOutputStream outputStream = new QueueOutputStream();
                 final QueueInputStream inputStream = outputStream.newQueueInputStream()) {
             outputStream.write("ABC".getBytes(UTF_8));
             final String value = IOUtils.toString(inputStream, UTF_8);
             assertEquals("ABC", value);
         }
     }
 
     @Test
     public void testWriteStringMultiThread() throws Exception {
         try (QueueOutputStream outputStream = callInThrowAwayThread(QueueOutputStream::new);
                 final QueueInputStream inputStream = callInThrowAwayThread(outputStream::newQueueInputStream)) {
             callInThrowAwayThread(() -> {
                 outputStream.write("ABC".getBytes(UTF_8));
                 return null;
             });
 
             final String value = callInThrowAwayThread(() -> IOUtils.toString(inputStream, UTF_8));
             assertEquals("ABC", value);
         }
     }
 }