/*
    * 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.comparator;
  
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertNotNull;
  import static org.junit.jupiter.api.Assertions.assertNull;
  import static org.junit.jupiter.api.Assertions.assertSame;
  import static org.junit.jupiter.api.Assertions.assertTrue;
  
  import java.io.File;
  import java.util.ArrayList;
  import java.util.Comparator;
  import java.util.List;
  
  import org.junit.jupiter.api.Test;
  import org.junit.jupiter.api.io.TempDir;
  
  /**
   * Base Test case for Comparator implementations.
   */
  public abstract class ComparatorAbstractTest {
  
      @TempDir
      public File dir;
  
      /** Comparator instance */
      protected AbstractFileComparator comparator;
  
      /** Reverse comparator instance */
      protected Comparator<File> reverse;
  
      /** File which compares equal to  "equalFile2" */
      protected File equalFile1;
  
      /** File which compares equal to  "equalFile1" */
      protected File equalFile2;
  
      /** File which is less than the "moreFile" */
      protected File lessFile;
  
      /** File which is more than the "lessFile" */
      protected File moreFile;
  
      /**
       * Test the comparator.
       */
      @Test
      public void testComparator() {
          assertEquals(0, comparator.compare(equalFile1, equalFile2), "equal");
          assertTrue(comparator.compare(lessFile, moreFile) < 0, "less");
          assertTrue(comparator.compare(moreFile, lessFile) > 0, "more");
      }
  
      /**
       * Test the comparator reversed.
       */
      @Test
      public void testReverseComparator() {
          assertEquals(0, reverse.compare(equalFile1, equalFile2), "equal");
          assertTrue(reverse.compare(moreFile, lessFile) < 0, "less");
          assertTrue(reverse.compare(lessFile, moreFile) > 0, "more");
      }
  
      /**
       * Test the comparator array sort.
       */
      @Test
      public void testSortArray() {
          final File[] files = new File[3];
          files[0] = equalFile1;
          files[1] = moreFile;
          files[2] = lessFile;
          comparator.sort(files);
          assertSame(lessFile, files[0], "equal");
          assertSame(equalFile1, files[1], "less");
          assertSame(moreFile, files[2], "more");
      }
  
      /**
       * Test comparator array sort is null safe.
       */
      @Test
      public void testSortArrayNull() {
          assertNull(comparator.sort((File[]) null));
     }
 
     /**
      * Test the comparator array sort.
      */
     @Test
     public void testSortList() {
         final List<File> files = new ArrayList<>();
         files.add(equalFile1);
         files.add(moreFile);
         files.add(lessFile);
         comparator.sort(files);
         assertSame(lessFile, files.get(0), "equal");
         assertSame(equalFile1, files.get(1), "less");
         assertSame(moreFile, files.get(2), "more");
     }
 
     /**
      * Test comparator list sort is null safe.
      */
     @Test
     public void testSortListNull() {
         assertNull(comparator.sort((List<File>) null));
     }
 
     /**
      * Test comparator toString.
      */
     @Test
     public void testToString() {
         assertNotNull(comparator.toString(), "comparator");
         assertTrue(reverse.toString().startsWith("ReverseFileComparator["), "reverse");
     }
 }