content: /*
   * 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 accord.burn.random;
  
  import accord.utils.Gen;
  import accord.utils.Gen.LongGen;
  import accord.utils.Gens;
  import accord.utils.RandomSource;
  
  import java.time.Duration;
  import java.util.concurrent.TimeUnit;
  
  import static accord.utils.Invariants.illegalState;
  
  public class FrequentLargeRange implements LongGen
  {
      private final LongGen small, large;
      private final Gen<Boolean> runs;
  
      public FrequentLargeRange(LongGen small, LongGen large, double ratio, int maxRuns)
      {
          this.small = small;
          this.large = large;
          this.runs = Gens.bools().biasedRepeatingRuns(ratio, maxRuns);
      }
  
      @Override
      public long nextLong(RandomSource randomSource)
      {
          if (runs.next(randomSource)) return large.nextLong(randomSource);
          else                         return small.nextLong(randomSource);
      }
  
      public static Builder builder(RandomSource randomSource)
      {
          return new Builder(randomSource);
      }
  
      public static class Builder
      {
          private final RandomSource random;
          private Double ratio;
          private Integer maxRuns;
          private LongGen small, large;
  
          public Builder(RandomSource random)
          {
              this.random = random;
          }
  
          public Builder ratio(double ratio)
          {
              this.ratio = ratio;
              return this;
          }
  
          public Builder ratio(int min, int max)
          {
              this.ratio = random.nextInt(min, max) / 100.0D;
              return this;
          }
  
          public Builder maxRuns(int maxRuns)
          {
              this.maxRuns = maxRuns;
              return this;
          }
  
          public Builder maxRuns(int min, int max)
          {
              this.maxRuns = random.nextInt(min, max);
              return this;
          }
  
          public Builder small(Duration min, Duration max)
          {
              small = create(min, max);
              return this;
          }
  
          public Builder small(long min, long max, TimeUnit unit)
          {
              small = create(min, max, unit);
              return this;
          }
  
          public Builder small(long min, TimeUnit minUnit, long max, TimeUnit maxUnit)
          {
              small = create(min, minUnit, max, maxUnit);
              return this;
          }
  
          public Builder large(Duration min, Duration max)
          {
              large = create(min, max);
              return this;
          }
  
          public Builder large(long min, long max, TimeUnit unit)
          {
              large = create(min, max, unit);
              return this;
          }
  
          public Builder large(long min, TimeUnit minUnit, long max, TimeUnit maxUnit)
          {
              large = create(min, minUnit, max, maxUnit);
              return this;
          }
  
          private RandomWalkRange create(Duration min, Duration max)
          {
              return new RandomWalkRange(random, min.toNanos(), max.toNanos());
          }
  
          private RandomWalkRange create(long min, long max, TimeUnit unit)
          {
              return create(min, unit, max, unit);
          }
  
          private RandomWalkRange create(long min, TimeUnit minUnit, long max, TimeUnit maxUnit)
          {
              return new RandomWalkRange(random, minUnit.toNanos(min), maxUnit.toNanos(max));
          }
  
          public FrequentLargeRange build()
          {
              if (small == null)
                  throw illegalState("Small range undefined");
              if (large == null)
                  throw illegalState("Large range undefined");
              if (ratio == null)
                  ratio(1, 11);
              if (maxRuns == null)
                  maxRuns(3, 15);
              return new FrequentLargeRange(small, large, ratio, maxRuns);
          }
      }
  }
  