/*
    * 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.rng;
  
  import java.util.Spliterator;
  import org.junit.jupiter.api.Assertions;
  
  /**
   * Tests for default stream method implementations in {@link UniformRandomProvider}.
   */
  class SplittableUniformRandomProviderStreamTest extends BaseRandomProviderStreamTest {
  
      /**
       * Dummy class for checking the behavior of the SplittableUniformRandomProvider.
       */
      private static class DummyGenerator implements SplittableUniformRandomProvider {
          /** An instance. */
          static final DummyGenerator INSTANCE = new DummyGenerator();
  
          @Override
          public long nextLong() {
              throw new UnsupportedOperationException("The nextLong method should not be invoked");
          }
  
          @Override
          public SplittableUniformRandomProvider split(UniformRandomProvider source) {
              throw new UnsupportedOperationException("The split method should not be invoked");
          }
      }
  
      @Override
      UniformRandomProvider create() {
          return DummyGenerator.INSTANCE;
      }
  
      @Override
      UniformRandomProvider createInts(int[] values) {
          return new DummyGenerator() {
              private int i;
              @Override
              public int nextInt() {
                  return values[i++];
              }
          };
      }
  
      @Override
      UniformRandomProvider createInts(int[] values, int origin, int bound) {
          return new DummyGenerator() {
              private int i;
              @Override
              public int nextInt(int o, int b) {
                  Assertions.assertEquals(origin, o, "origin");
                  Assertions.assertEquals(bound, b, "bound");
                  return values[i++];
              }
          };
      }
  
      @Override
      UniformRandomProvider createLongs(long[] values) {
          return new DummyGenerator() {
              private int i;
              @Override
              public long nextLong() {
                  return values[i++];
              }
          };
      }
  
      @Override
      UniformRandomProvider createLongs(long[] values, long origin, long bound) {
          return new DummyGenerator() {
              private int i;
              @Override
              public long nextLong(long o, long b) {
                  Assertions.assertEquals(origin, o, "origin");
                  Assertions.assertEquals(bound, b, "bound");
                  return values[i++];
              }
          };
      }
  
      @Override
      UniformRandomProvider createDoubles(double[] values) {
         return new DummyGenerator() {
             private int i;
             @Override
             public double nextDouble() {
                 return values[i++];
             }
         };
     }
 
     @Override
     UniformRandomProvider createDoubles(double[] values, double origin, double bound) {
         return new DummyGenerator() {
             private int i;
             @Override
             public double nextDouble(double o, double b) {
                 Assertions.assertEquals(origin, o, "origin");
                 Assertions.assertEquals(bound, b, "bound");
                 return values[i++];
             }
         };
     }
 
     @Override
     int getCharacteristics() {
         // Since this is splittable it supports sized and sub-sized.
         // Add non-null although this may not be relevant for primitive streams.
         return Spliterator.SIZED | Spliterator.SUBSIZED | Spliterator.NONNULL | Spliterator.IMMUTABLE;
     }
 }