/*
    * 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 org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  
  import java.io.IOException;
  import java.io.OutputStreamWriter;
  import java.util.concurrent.atomic.AtomicInteger;
  
  import org.apache.commons.io.IOUtils;
  import org.junit.jupiter.api.Test;
  
  /**
   * Tests {@link ChunkedWriter}.
   */
  public class ChunkedWriterTest {
  
      @SuppressWarnings("resource") // closed by caller.
      private OutputStreamWriter getOutputStreamWriter(final AtomicInteger numWrites) {
          final ByteArrayOutputStream baos = new ByteArrayOutputStream();
          return new OutputStreamWriter(baos) {
              @Override
              public void write(final char[] cbuf, final int off, final int len) throws IOException {
                  numWrites.incrementAndGet();
                  super.write(cbuf, off, len);
              }
          };
      }
  
      @Test
      public void testNegative_chunkSize_not_permitted() {
          assertThrows(IllegalArgumentException.class,
                 () -> new ChunkedWriter(new OutputStreamWriter(new ByteArrayOutputStream()), 0));
      }
  
      @Test
      public void testWrite_four_chunks() throws Exception {
          final AtomicInteger numWrites = new AtomicInteger();
          try (OutputStreamWriter osw = getOutputStreamWriter(numWrites)) {
              try (ChunkedWriter chunked = new ChunkedWriter(osw, 10)) {
                  chunked.write("0123456789012345678901234567891".toCharArray());
                  chunked.flush();
                  assertEquals(4, numWrites.get());
              }
          }
      }
  
      @Test
      public void testWrite_two_chunks_default_constructor() throws Exception {
          final AtomicInteger numWrites = new AtomicInteger();
          try (OutputStreamWriter osw = getOutputStreamWriter(numWrites)) {
              try (ChunkedWriter chunked = new ChunkedWriter(osw)) {
                  chunked.write(new char[IOUtils.DEFAULT_BUFFER_SIZE + 1]);
                  chunked.flush();
                  assertEquals(2, numWrites.get());
              }
          }
      }
  }