/*
    * 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.statistics.distribution;
  
  import java.util.stream.Stream;
  import org.junit.jupiter.params.ParameterizedTest;
  import org.junit.jupiter.params.provider.Arguments;
  import org.junit.jupiter.params.provider.MethodSource;
  
  /**
   * Test cases for {@link PascalDistribution}.
   * Extends {@link BaseDiscreteDistributionTest}. See javadoc of that class for details.
   */
  class PascalDistributionTest extends BaseDiscreteDistributionTest {
      @Override
      DiscreteDistribution makeDistribution(Object... parameters) {
          final int r = (Integer) parameters[0];
          final double p = (Double) parameters[1];
          return PascalDistribution.of(r, p);
      }
  
  
      @Override
      Object[][] makeInvalidParameters() {
          return new Object[][] {
              {0, 0.5},
              {-1, 0.5},
              {3, -0.1},
              {3, 0.0},
              {3, 1.1},
          };
      }
  
      @Override
      String[] getParameterNames() {
          return new String[] {"NumberOfSuccesses", "ProbabilityOfSuccess"};
      }
  
      @Override
      protected double getRelativeTolerance() {
          return 5e-15;
      }
  
      //-------------------- Additional test cases -------------------------------
  
      @ParameterizedTest
      @MethodSource
      void testAdditionalMoments(int r, double p, double mean, double variance) {
          final PascalDistribution dist = PascalDistribution.of(r, p);
          testMoments(dist, mean, variance, DoubleTolerances.ulps(1));
      }
  
      static Stream<Arguments> testAdditionalMoments() {
          return Stream.of(
              Arguments.of(10, 0.5, (10d * 0.5d) / 0.5, (10d * 0.5d) / (0.5d * 0.5d)),
              Arguments.of(25, 0.7, (25d * 0.3d) / 0.7, (25d * 0.3d) / (0.7d * 0.7d))
          );
      }
  }