RandomWrapper.h

//-------------------------------------------------------------------------------------------------------
// Copyright (C) Taylor Woll and panga contributors. All rights reserved.
// Licensed under the MIT license. See LICENSE.txt file in the project root for
// full license information.
//-------------------------------------------------------------------------------------------------------
 
#ifndef RANDOMWRAPPER_H__
#define RANDOMWRAPPER_H__
 
#include <algorithm>
#include <cstddef>
#include <cstdint>
#include <optional>
#include <random>
#include <vector>
 
namespace panann {
 
class RandomWrapper {
 public:
  RandomWrapper() = default;
  RandomWrapper(const RandomWrapper& rhs) = delete;
  RandomWrapper& operator=(const RandomWrapper& rhs) = delete;
  ~RandomWrapper() = default;
 
  template <typename IntegerType = uint32_t>
  IntegerType RandomInteger(IntegerType min, IntegerType max) {
    std::uniform_int_distribution<IntegerType> dist(min, max);
    return dist(Engine());
  }
 
  template <typename FloatType = double>
  FloatType RandomFloat(FloatType min, FloatType max) {
    std::uniform_real_distribution<FloatType> dist(min, max);
    return dist(Engine());
  }
 
  bool CoinFlip(double probability);
 
  std::byte RandomByte();
 
  template <typename T>
  void ShuffleVector(std::vector<T>* vec) {
    std::shuffle(vec->begin(), vec->end(), Engine());
  }
 
 protected:
  std::mt19937& Engine();
 
 private:
  std::optional<std::mt19937> engine_;
};
 
}  // namespace panann
 
#endif  // RANDOMWRAPPER_H__