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#ifndef GMX_SIMD_IMPLEMENTATION_IBM_VMX_SIMD_FLOAT_H
#define GMX_SIMD_IMPLEMENTATION_IBM_VMX_SIMD_FLOAT_H

#include "config.h"

#include <cstdint>

#include "gromacs/math/utilities.h"
#include "gromacs/utility/basedefinitions.h"

#include "impl_ibm_vmx_definitions.h"

namespace gmx
{

class SimdFloat
{
public:
    SimdFloat() {}

    SimdFloat(float f)
    {
        __vector unsigned char perm;

        simdInternal_ = vec_lde(0, const_cast<float*>(&f));
        perm          = vec_lvsl(0, const_cast<float*>(&f));
        simdInternal_ = vec_perm(simdInternal_, simdInternal_, perm);
        simdInternal_ = vec_splat(simdInternal_, 0);
    }

    // Internal utility constructor to simplify return statements
    SimdFloat(__vector float simd) : simdInternal_(simd) {}

    __vector float simdInternal_;
};

class SimdFInt32
{
public:
    SimdFInt32() {}

    SimdFInt32(std::int32_t i)
    {
        __vector unsigned char perm;

        simdInternal_ = vec_lde(0, const_cast<int*>(&i));
        perm          = vec_lvsl(0, const_cast<int*>(&i));
        simdInternal_ = vec_perm(simdInternal_, simdInternal_, perm);
        simdInternal_ = vec_splat(simdInternal_, 0);
    }


    // Internal utility constructor to simplify return statements
    SimdFInt32(__vector signed int simd) : simdInternal_(simd) {}

    __vector signed int simdInternal_;
};

class SimdFBool
{
public:
    SimdFBool() {}

    SimdFBool(bool b) :
        simdInternal_(reinterpret_cast<__vector vmxBool int>(vec_splats(b ? 0xFFFFFFFF : 0)))
    {
    }

    // Internal utility constructor to simplify return statements
    SimdFBool(__vector vmxBool int simd) : simdInternal_(simd) {}

    __vector vmxBool int simdInternal_;
};

class SimdFIBool
{
public:
    SimdFIBool() {}

    SimdFIBool(bool b) :
        simdInternal_(reinterpret_cast<__vector vmxBool int>(vec_splat_u32(b ? 0xFFFFFFFF : 0)))
    {
    }

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

    __vector vmxBool int simdInternal_;
};

static inline SimdFloat gmx_simdcall simdLoad(const float* m, SimdFloatTag = {})
{
    return { vec_ld(0, const_cast<float*>(m)) };
}

static inline void gmx_simdcall store(float* m, SimdFloat a)
{
    vec_st(a.simdInternal_, 0, const_cast<float*>(m));
}

static inline SimdFloat gmx_simdcall setZeroF()
{
    return { reinterpret_cast<__vector float>(vec_splat_u32(0)) };
}

static inline SimdFInt32 gmx_simdcall simdLoad(const std::int32_t* m, SimdFInt32Tag)
{
    return { vec_ld(0, const_cast<int*>(m)) };
}

static inline void gmx_simdcall store(std::int32_t* m, SimdFInt32 a)
{
    vec_st(a.simdInternal_, 0, const_cast<int*>(m));
}

static inline SimdFInt32 gmx_simdcall setZeroFI()
{
    return { vec_splat_s32(0) };
}

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

static inline SimdFloat gmx_simdcall andNot(SimdFloat a, SimdFloat b)
{
    return { vec_andc(b.simdInternal_, a.simdInternal_) };
}

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

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

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

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

static inline SimdFloat gmx_simdcall operator-(SimdFloat x)
{
    return { vec_xor(x.simdInternal_,
                     reinterpret_cast<__vector float>(vec_sl(vec_splat_u32(-1), vec_splat_u32(-1)))) };
}

static inline SimdFloat gmx_simdcall operator*(SimdFloat a, SimdFloat b)
{
    return { vec_madd(a.simdInternal_, b.simdInternal_,
                      reinterpret_cast<__vector float>(vec_splat_u32(0))) };
}

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

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

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

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

static inline SimdFloat gmx_simdcall rsqrt(SimdFloat x)
{
    return { vec_rsqrte(x.simdInternal_) };
}

static inline SimdFloat gmx_simdcall rcp(SimdFloat x)
{
    return { vec_re(x.simdInternal_) };
}

static inline SimdFloat gmx_simdcall maskAdd(SimdFloat a, SimdFloat b, SimdFBool m)
{
    return { vec_add(a.simdInternal_,
                     vec_and(b.simdInternal_, reinterpret_cast<__vector float>(m.simdInternal_))) };
}

static inline SimdFloat gmx_simdcall maskzMul(SimdFloat a, SimdFloat b, SimdFBool m)
{
    SimdFloat prod = a * b;

    return { vec_and(prod.simdInternal_, reinterpret_cast<__vector float>(m.simdInternal_)) };
}

static inline SimdFloat gmx_simdcall maskzFma(SimdFloat a, SimdFloat b, SimdFloat c, SimdFBool m)
{
    SimdFloat prod = fma(a, b, c);

    return { vec_and(prod.simdInternal_, reinterpret_cast<__vector float>(m.simdInternal_)) };
}

static inline SimdFloat gmx_simdcall maskzRsqrt(SimdFloat x, SimdFBool m)
{
#ifndef NDEBUG
    SimdFloat one(1.0F);
    x.simdInternal_ = vec_sel(one.simdInternal_, x.simdInternal_, m.simdInternal_);
#endif
    return { vec_and(vec_rsqrte(x.simdInternal_), reinterpret_cast<__vector float>(m.simdInternal_)) };
}

static inline SimdFloat gmx_simdcall maskzRcp(SimdFloat x, SimdFBool m)
{
#ifndef NDEBUG
    SimdFloat one(1.0F);
    x.simdInternal_ = vec_sel(one.simdInternal_, x.simdInternal_, m.simdInternal_);
#endif
    return { vec_and(vec_re(x.simdInternal_), reinterpret_cast<__vector float>(m.simdInternal_)) };
}

static inline SimdFloat gmx_simdcall abs(SimdFloat x)
{
    return { vec_abs(x.simdInternal_) };
}

static inline SimdFloat gmx_simdcall max(SimdFloat a, SimdFloat b)
{
    return { vec_max(a.simdInternal_, b.simdInternal_) };
}

static inline SimdFloat gmx_simdcall min(SimdFloat a, SimdFloat b)
{
    return { vec_min(a.simdInternal_, b.simdInternal_) };
}

static inline SimdFloat gmx_simdcall round(SimdFloat x)
{
    return { vec_round(x.simdInternal_) };
}

static inline SimdFloat gmx_simdcall trunc(SimdFloat x)
{
    return { vec_trunc(x.simdInternal_) };
}

template<MathOptimization opt = MathOptimization::Safe>
static inline SimdFloat gmx_simdcall frexp(SimdFloat value, SimdFInt32* exponent)
{
    // Generate constants without memory operations
    const __vector signed int exponentMask =
            vec_sl(vec_add(vec_splat_s32(15), vec_sl(vec_splat_s32(15), vec_splat_u32(4))),
                   vec_add(vec_splat_u32(15), vec_splat_u32(8))); // 0x7F800000
    const __vector signed int exponentBias =
            vec_sub(vec_sl(vec_splat_s32(1), vec_splat_u32(7)), vec_splat_s32(2)); // 126
    const SimdFloat     half(0.5F);
    __vector signed int iExponent;

    __vector vmxBool int valueIsZero =
            vec_cmpeq(value.simdInternal_, reinterpret_cast<__vector float>(vec_splat_u32(0)));

    iExponent = vec_and(reinterpret_cast<__vector signed int>(value.simdInternal_), exponentMask);
    iExponent = vec_sr(iExponent, vec_add(vec_splat_u32(15), vec_splat_u32(8)));
    iExponent = vec_sub(iExponent, exponentBias);
    iExponent = vec_andc(iExponent, reinterpret_cast<__vector int>(valueIsZero));

    __vector float result =
            vec_or(vec_andc(value.simdInternal_, reinterpret_cast<__vector float>(exponentMask)),
                   half.simdInternal_);
    result = vec_sel(result, value.simdInternal_, valueIsZero);

    exponent->simdInternal_ = iExponent;

    return { result };
}

template<MathOptimization opt = MathOptimization::Safe>
static inline SimdFloat gmx_simdcall ldexp(SimdFloat value, SimdFInt32 exponent)
{
    const __vector signed int exponentBias =
            vec_sub(vec_sl(vec_splat_s32(1), vec_splat_u32(7)), vec_splat_s32(1)); // 127
    __vector signed int iExponent;

    iExponent = vec_add(exponent.simdInternal_, exponentBias);

    if (opt == MathOptimization::Safe)
    {
        // Make sure biased argument is not negative
        iExponent = vec_max(iExponent, vec_splat_s32(0));
    }

    iExponent = vec_sl(iExponent, vec_add(vec_splat_u32(15), vec_splat_u32(8)));

    return { vec_madd(value.simdInternal_, reinterpret_cast<__vector float>(iExponent),
                      reinterpret_cast<__vector float>(vec_splat_u32(0))) };
}

static inline float gmx_simdcall reduce(SimdFloat a)
{
    __vector float c = a.simdInternal_;
    float          res;

    // calculate sum
    c = vec_add(c, vec_sld(c, c, 8));
    c = vec_add(c, vec_sld(c, c, 4));
    vec_ste(c, 0, &res);
    return res;
}

static inline SimdFBool gmx_simdcall operator==(SimdFloat a, SimdFloat b)
{
    return { vec_cmpeq(a.simdInternal_, b.simdInternal_) };
}

static inline SimdFBool gmx_simdcall operator!=(SimdFloat a, SimdFloat b)
{
    return { vec_or(vec_cmpgt(a.simdInternal_, b.simdInternal_),
                    vec_cmplt(a.simdInternal_, b.simdInternal_)) };
}

static inline SimdFBool gmx_simdcall operator<(SimdFloat a, SimdFloat b)
{
    return { vec_cmplt(a.simdInternal_, b.simdInternal_) };
}

static inline SimdFBool gmx_simdcall operator<=(SimdFloat a, SimdFloat b)
{
    return { vec_cmple(a.simdInternal_, b.simdInternal_) };
}

static inline SimdFBool gmx_simdcall testBits(SimdFloat a)
{
    return { vec_cmpgt(reinterpret_cast<__vector unsigned int>(a.simdInternal_), vec_splat_u32(0)) };
}

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

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

static inline bool gmx_simdcall anyTrue(SimdFBool a)
{
    return vec_any_ne(a.simdInternal_, reinterpret_cast<__vector vmxBool int>(vec_splat_u32(0)));
}

static inline SimdFloat gmx_simdcall selectByMask(SimdFloat a, SimdFBool m)
{
    return { vec_and(a.simdInternal_, reinterpret_cast<__vector float>(m.simdInternal_)) };
}

static inline SimdFloat gmx_simdcall selectByNotMask(SimdFloat a, SimdFBool m)
{
    return { vec_andc(a.simdInternal_, reinterpret_cast<__vector float>(m.simdInternal_)) };
}

static inline SimdFloat gmx_simdcall blend(SimdFloat a, SimdFloat b, SimdFBool sel)
{
    return { vec_sel(a.simdInternal_, b.simdInternal_, sel.simdInternal_) };
}

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

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

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

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

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

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

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

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

static inline SimdFIBool gmx_simdcall testBits(SimdFInt32 a)
{
    return { vec_cmpgt(reinterpret_cast<__vector unsigned int>(a.simdInternal_), vec_splat_u32(0)) };
}

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

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

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

static inline bool gmx_simdcall anyTrue(SimdFIBool a)
{
    return vec_any_ne(a.simdInternal_, reinterpret_cast<__vector vmxBool int>(vec_splat_u32(0)));
}

static inline SimdFInt32 gmx_simdcall selectByMask(SimdFInt32 a, SimdFIBool m)
{
    return { vec_and(a.simdInternal_, reinterpret_cast<__vector signed int>(m.simdInternal_)) };
}

static inline SimdFInt32 gmx_simdcall selectByNotMask(SimdFInt32 a, SimdFIBool m)
{
    return { vec_andc(a.simdInternal_, reinterpret_cast<__vector signed int>(m.simdInternal_)) };
}

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

static inline SimdFInt32 gmx_simdcall cvtR2I(SimdFloat a)
{
    return { vec_cts(vec_round(a.simdInternal_), 0) };
}

static inline SimdFInt32 gmx_simdcall cvttR2I(SimdFloat a)
{
    return { vec_cts(a.simdInternal_, 0) };
}

static inline SimdFloat gmx_simdcall cvtI2R(SimdFInt32 a)
{
    return { vec_ctf(a.simdInternal_, 0) };
}

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

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

} // namespace gmx

#endif // GMX_SIMD_IMPLEMENTATION_IBM_VMX_SIMD_FLOAT_H
