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#ifndef GMX_SIMD_IMPL_X86_AVX2_256_SIMD_FLOAT_H
#define GMX_SIMD_IMPL_X86_AVX2_256_SIMD_FLOAT_H

#include "config.h"

#include <immintrin.h>

#include "gromacs/math/utilities.h"
#include "gromacs/simd/impl_x86_avx_256/impl_x86_avx_256_simd_float.h"

namespace gmx
{

class SimdFIBool
{
public:
    MSVC_DIAGNOSTIC_IGNORE(26495) // simdInternal_ is not being initialized!
    SimdFIBool() {}
    MSVC_DIAGNOSTIC_RESET
    SimdFIBool(bool b) : simdInternal_(_mm256_set1_epi32(b ? 0xFFFFFFFF : 0)) {}

    // Internal utility constructor to simplify return statements
    SimdFIBool(__m256i simd) : simdInternal_(simd) {}

    __m256i simdInternal_;
};

static inline SimdFloat gmx_simdcall fma(SimdFloat a, SimdFloat b, SimdFloat c)
{
    return { _mm256_fmadd_ps(a.simdInternal_, b.simdInternal_, c.simdInternal_) };
}

static inline SimdFloat gmx_simdcall fms(SimdFloat a, SimdFloat b, SimdFloat c)
{
    return { _mm256_fmsub_ps(a.simdInternal_, b.simdInternal_, c.simdInternal_) };
}

static inline SimdFloat gmx_simdcall fnma(SimdFloat a, SimdFloat b, SimdFloat c)
{
    return { _mm256_fnmadd_ps(a.simdInternal_, b.simdInternal_, c.simdInternal_) };
}

static inline SimdFloat gmx_simdcall fnms(SimdFloat a, SimdFloat b, SimdFloat c)
{
    return { _mm256_fnmsub_ps(a.simdInternal_, b.simdInternal_, c.simdInternal_) };
}

static inline SimdFBool gmx_simdcall testBits(SimdFloat a)
{
    __m256i ia  = _mm256_castps_si256(a.simdInternal_);
    __m256i res = _mm256_andnot_si256(_mm256_cmpeq_epi32(ia, _mm256_setzero_si256()),
                                      _mm256_cmpeq_epi32(ia, ia));

    return { _mm256_castsi256_ps(res) };
}

static inline SimdFloat gmx_simdcall frexp(SimdFloat value, SimdFInt32* exponent)
{
    const __m256  exponentMask = _mm256_castsi256_ps(_mm256_set1_epi32(0x7F800000));
    const __m256  mantissaMask = _mm256_castsi256_ps(_mm256_set1_epi32(0x807FFFFF));
    const __m256i exponentBias = _mm256_set1_epi32(126); // add 1 to make our definition identical to frexp()
    const __m256  half = _mm256_set1_ps(0.5);
    __m256i       iExponent;

    iExponent               = _mm256_castps_si256(_mm256_and_ps(value.simdInternal_, exponentMask));
    exponent->simdInternal_ = _mm256_sub_epi32(_mm256_srli_epi32(iExponent, 23), exponentBias);

    return { _mm256_or_ps(_mm256_and_ps(value.simdInternal_, mantissaMask), half) };
}

template<MathOptimization opt = MathOptimization::Safe>
static inline SimdFloat gmx_simdcall ldexp(SimdFloat value, SimdFInt32 exponent)
{
    const __m256i exponentBias = _mm256_set1_epi32(127);
    __m256i       iExponent    = _mm256_add_epi32(exponent.simdInternal_, exponentBias);

    if (opt == MathOptimization::Safe)
    {
        // Make sure biased argument is not negative
        iExponent = _mm256_max_epi32(iExponent, _mm256_setzero_si256());
    }

    iExponent = _mm256_slli_epi32(iExponent, 23);
    return { _mm256_mul_ps(value.simdInternal_, _mm256_castsi256_ps(iExponent)) };
}

static inline SimdFInt32 gmx_simdcall operator&(SimdFInt32 a, SimdFInt32 b)
{
    return { _mm256_and_si256(a.simdInternal_, b.simdInternal_) };
}

static inline SimdFInt32 gmx_simdcall andNot(SimdFInt32 a, SimdFInt32 b)
{
    return { _mm256_andnot_si256(a.simdInternal_, b.simdInternal_) };
}

static inline SimdFInt32 gmx_simdcall operator|(SimdFInt32 a, SimdFInt32 b)
{
    return { _mm256_or_si256(a.simdInternal_, b.simdInternal_) };
}

static inline SimdFInt32 gmx_simdcall operator^(SimdFInt32 a, SimdFInt32 b)
{
    return { _mm256_xor_si256(a.simdInternal_, b.simdInternal_) };
}

static inline SimdFInt32 gmx_simdcall operator+(SimdFInt32 a, SimdFInt32 b)
{
    return { _mm256_add_epi32(a.simdInternal_, b.simdInternal_) };
}

static inline SimdFInt32 gmx_simdcall operator-(SimdFInt32 a, SimdFInt32 b)
{
    return { _mm256_sub_epi32(a.simdInternal_, b.simdInternal_) };
}

static inline SimdFInt32 gmx_simdcall operator*(SimdFInt32 a, SimdFInt32 b)
{
    return { _mm256_mullo_epi32(a.simdInternal_, b.simdInternal_) };
}

static inline SimdFIBool gmx_simdcall operator==(SimdFInt32 a, SimdFInt32 b)
{
    return { _mm256_cmpeq_epi32(a.simdInternal_, b.simdInternal_) };
}

static inline SimdFIBool gmx_simdcall testBits(SimdFInt32 a)
{
    return { _mm256_andnot_si256(_mm256_cmpeq_epi32(a.simdInternal_, _mm256_setzero_si256()),
                                 _mm256_cmpeq_epi32(a.simdInternal_, a.simdInternal_)) };
}

static inline SimdFIBool gmx_simdcall operator<(SimdFInt32 a, SimdFInt32 b)
{
    return { _mm256_cmpgt_epi32(b.simdInternal_, a.simdInternal_) };
}

static inline SimdFIBool gmx_simdcall operator&&(SimdFIBool a, SimdFIBool b)
{
    return { _mm256_and_si256(a.simdInternal_, b.simdInternal_) };
}

static inline SimdFIBool gmx_simdcall operator||(SimdFIBool a, SimdFIBool b)
{
    return { _mm256_or_si256(a.simdInternal_, b.simdInternal_) };
}

static inline bool gmx_simdcall anyTrue(SimdFIBool a)
{
    return _mm256_movemask_epi8(a.simdInternal_) != 0;
}

static inline SimdFInt32 gmx_simdcall selectByMask(SimdFInt32 a, SimdFIBool mask)
{
    return { _mm256_and_si256(a.simdInternal_, mask.simdInternal_) };
}

static inline SimdFInt32 gmx_simdcall selectByNotMask(SimdFInt32 a, SimdFIBool mask)
{
    return { _mm256_andnot_si256(mask.simdInternal_, a.simdInternal_) };
}

static inline SimdFInt32 gmx_simdcall blend(SimdFInt32 a, SimdFInt32 b, SimdFIBool sel)
{
    return { _mm256_blendv_epi8(a.simdInternal_, b.simdInternal_, sel.simdInternal_) };
}

static inline SimdFIBool gmx_simdcall cvtB2IB(SimdFBool a)
{
    return { _mm256_castps_si256(a.simdInternal_) };
}

static inline SimdFBool gmx_simdcall cvtIB2B(SimdFIBool a)
{
    return { _mm256_castsi256_ps(a.simdInternal_) };
}

} // namespace gmx

#endif // GMX_SIMD_IMPL_X86_AVX2_256_SIMD_FLOAT_H
