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#pragma once
#ifndef TESTING_RANDOM_HPP
#define TESTING_RANDOM_HPP

#include <algorithm>
#include <complex>
#include <random>
#include <string>

/* ==================================================================================== */
// Random number generator

using rocalution_rng_t = std::mt19937;

void rocalution_rng_set(rocalution_rng_t a);

void rocalution_seed_set(rocalution_rng_t a);

rocalution_rng_t& rocalution_rng_get();

rocalution_rng_t& rocalution_seed_get();

// Reset the seed (mainly to ensure repeatability of failures in a given suite)
inline void rocalution_seedrand()
{
    rocalution_rng_set(rocalution_seed_get());
}

/* ==================================================================================== */
/* generate random number :*/

/*! \brief  generate a random number in range [a,b] */

template <typename T>
inline T random_generator_exact(int a = 1, int b = 10)
{
    return std::uniform_int_distribution<int>(a, b)(rocalution_rng_get());
}

template <>
inline std::complex<float> random_generator_exact<std::complex<float>>(int a, int b)
{
    return std::complex<float>(random_generator_exact<float>(a, b),
                               random_generator_exact<float>(a, b));
}

template <>
inline std::complex<double> random_generator_exact<std::complex<double>>(int a, int b)
{
    return std::complex<double>(random_generator_exact<double>(a, b),
                                random_generator_exact<double>(a, b));
}

template <typename T, typename std::enable_if_t<std::is_integral<T>::value, bool> = true>
inline T random_generator(T a = static_cast<T>(1), T b = static_cast<T>(10))
{
    return random_generator_exact<T>(a, b);
}

template <typename T, typename std::enable_if_t<!std::is_integral<T>::value, bool> = true>
inline T random_generator(T a = static_cast<T>(0), T b = static_cast<T>(1))
{
    return std::uniform_real_distribution<T>(a, b)(rocalution_rng_get());
}

template <>
inline std::complex<float> random_generator<std::complex<float>>(std::complex<float> a,
                                                                 std::complex<float> b)
{
    float theta = random_generator<float>(0.0f, 2.0f * acos(-1.0f));
    float r     = random_generator<float>(std::abs(a), std::abs(b));

    return std::complex<float>(r * cos(theta), r * sin(theta));
}

template <>
inline std::complex<double> random_generator<std::complex<double>>(std::complex<double> a,
                                                                   std::complex<double> b)
{
    double theta = random_generator<double>(0.0, 2.0 * acos(-1.0));
    double r     = random_generator<double>(std::abs(a), std::abs(b));

    return std::complex<double>(r * cos(theta), r * sin(theta));
}

#endif // TESTING_RANDOM_HPP