/*
    * 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
    *
    *      https://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.function;
  
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertFalse;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  import static org.junit.jupiter.api.Assertions.assertTrue;
  
  import java.io.IOException;
  import java.nio.file.Path;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Iterator;
  import java.util.List;
  
  import org.apache.commons.lang3.JavaVersion;
  import org.apache.commons.lang3.SystemUtils;
  import org.junit.jupiter.api.BeforeEach;
  import org.junit.jupiter.api.Test;
  
  /**
   * Tests {@link IOIterator}.
   */
  class IOIteratorTest {
  
      private IOIterator<Path> iterator;
  
      @BeforeEach
      public void beforeEach() {
          iterator = IOIterator.adapt(newPathList().iterator());
      }
  
      private List<Path> newPathList() {
          return Arrays.asList(TestConstants.ABS_PATH_A, TestConstants.ABS_PATH_B);
      }
  
      @Test
      void testAdaptIterable() throws IOException {
          assertEquals(TestConstants.ABS_PATH_A, IOIterator.adapt(newPathList()).next());
      }
  
      @Test
      void testAdaptIterator() throws IOException {
          assertEquals(TestConstants.ABS_PATH_A, iterator.next());
      }
  
      @Test
      void testAsIterator() {
          final Iterator<Path> asIterator = iterator.asIterator();
          assertTrue(asIterator.hasNext());
          assertEquals(TestConstants.ABS_PATH_A, asIterator.next());
          assertThrows(UnsupportedOperationException.class, asIterator::remove);
      }
  
      @Test
      void testForEachRemaining() throws IOException {
          final List<Path> list = new ArrayList<>();
          iterator.forEachRemaining(p -> list.add(p.toRealPath()));
          assertFalse(iterator.hasNext());
          assertEquals(newPathList(), list);
      }
  
      @Test
      void testHasNext() throws IOException {
          assertTrue(iterator.hasNext());
          iterator.forEachRemaining(Path::toRealPath);
          assertFalse(iterator.hasNext());
      }
  
      @Test
      void testNext() throws IOException {
          assertEquals(TestConstants.ABS_PATH_A, iterator.next());
      }
  
      @Test
      void testRemove() throws IOException {
          final Class<? extends Exception> exClass = SystemUtils.isJavaVersionAtMost(JavaVersion.JAVA_1_8) ? IllegalStateException.class
              : UnsupportedOperationException.class;
          assertThrows(exClass, iterator::remove);
          assertThrows(exClass, iterator::remove);
          iterator.next();
          assertThrows(UnsupportedOperationException.class, iterator::remove);
          assertThrows(UnsupportedOperationException.class, iterator::remove);
     }
 
 }