/*
    * 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.compress.compressors.lz77support;
  
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  
  import org.junit.jupiter.api.Test;
  
  public class ParametersTest {
  
      private static Parameters newParameters(final int windowSize) {
          return Parameters.builder(windowSize).build();
      }
  
      private static Parameters newParameters(final int windowSize, final int minBackReferenceLength, final int maxBackReferenceLength, final int maxOffset,
              final int maxLiteralLength) {
          return Parameters.builder(windowSize).withMinBackReferenceLength(minBackReferenceLength).withMaxBackReferenceLength(maxBackReferenceLength)
                  .withMaxOffset(maxOffset).withMaxLiteralLength(maxLiteralLength).build();
      }
  
      @Test
      public void testAllParametersUsuallyTakeTheirSpecifiedValues() {
          final Parameters p = newParameters(256, 4, 5, 6, 7);
          assertEquals(256, p.getWindowSize());
          assertEquals(4, p.getMinBackReferenceLength());
          assertEquals(5, p.getMaxBackReferenceLength());
          assertEquals(6, p.getMaxOffset());
          assertEquals(7, p.getMaxLiteralLength());
      }
  
      @Test
      public void testDefaultConstructor() {
          final Parameters p = newParameters(128);
          assertEquals(128, p.getWindowSize());
          assertEquals(3, p.getMinBackReferenceLength());
          assertEquals(127, p.getMaxBackReferenceLength());
          assertEquals(127, p.getMaxOffset());
          assertEquals(128, p.getMaxLiteralLength());
      }
  
      @Test
      public void testMaxBackReferenceLengthIsMinBackReferenceLengthIfBothAreEqual() {
          final Parameters p = newParameters(128, 2, 3, 4, 5);
          assertEquals(3, p.getMaxBackReferenceLength());
      }
  
      @Test
      public void testMaxBackReferenceLengthIsMinBackReferenceLengthWhenSmallerThanMinBackReferenceLength() {
          final Parameters p = newParameters(128, 2, 2, 4, 5);
          assertEquals(3, p.getMaxBackReferenceLength());
      }
  
      @Test
      public void testMaxBackReferenceLengthIsMinBackReferenceLengthWhenSmallerThanMinBackReferenceLengthReversedInvocationOrder() {
          final Parameters p = Parameters.builder(128).withMaxBackReferenceLength(2).withMinBackReferenceLength(2).withMaxOffset(4).withMaxLiteralLength(5)
                  .build();
          assertEquals(3, p.getMaxBackReferenceLength());
      }
  
      @Test
      public void testMaxLiteralLengthIsWindowSizeIfSetTo0() {
          final Parameters p = newParameters(128, 2, 3, 4, 0);
          assertEquals(128, p.getMaxLiteralLength());
      }
  
      @Test
      public void testMaxLiteralLengthIsWindowSizeIfSetToANegativeValue() {
          final Parameters p = newParameters(128, 2, 3, 0, -1);
          assertEquals(128, p.getMaxLiteralLength());
      }
  
      @Test
      public void testMaxLiteralLengthIsWindowSizeIfSetToAValueTooBigToHoldInSlidingWindow() {
          final Parameters p = newParameters(128, 2, 3, 0, 259);
          assertEquals(128, p.getMaxLiteralLength());
      }
  
      @Test
      public void testMaxOffsetIsWindowSizeMinus1IfBiggerThanWindowSize() {
          final Parameters p = newParameters(128, 2, 3, 129, 5);
          assertEquals(127, p.getMaxOffset());
      }
 
     @Test
     public void testMaxOffsetIsWindowSizeMinus1IfSetTo0() {
         final Parameters p = newParameters(128, 2, 3, 0, 5);
         assertEquals(127, p.getMaxOffset());
     }
 
     @Test
     public void testMaxOffsetIsWindowSizeMinus1IfSetToANegativeValue() {
         final Parameters p = newParameters(128, 2, 3, -1, 5);
         assertEquals(127, p.getMaxOffset());
     }
 
     @Test
     public void testMinBackReferenceLengthIsAtLeastThree() {
         final Parameters p = newParameters(128, 2, 3, 4, 5);
         assertEquals(3, p.getMinBackReferenceLength());
     }
 
     @Test
     public void testWindowSizeMustBeAPowerOfTwo() {
         assertThrows(IllegalArgumentException.class, () -> newParameters(100, 200, 300, 400, 500));
     }
 
     @Test
     public void testWindowSizeMustNotBeSmallerThanMinBackReferenceLength() {
         assertThrows(IllegalArgumentException.class, () -> newParameters(128, 200, 300, 400, 500));
     }
 }