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#pragma once

///////////////////////////////////////////////////////////////////////////////

namespace cutlass::epilogue::collective::detail {

///////////////////////////////////////////////////////////////////////////////

// Selects the largest vectorized smem store atom available
template <class GmemStrideTypeD, class ElementD, class EpilogueTile_MN>
constexpr auto
sm90_get_smem_store_op_for_accumulator() {
  using namespace cute;

  if constexpr (sizeof(ElementD) == 2 && size<0>(GmemStrideTypeD{}) == 1) {
    if constexpr (size<1>(EpilogueTile_MN{}) % 16 == 0) {
      return SM90_U16x8_STSM_T{};
    }
    else if constexpr (size<1>(EpilogueTile_MN{}) % 8 == 0) {
      return SM90_U16x4_STSM_T{};
    }
  }
  else if constexpr (sizeof(ElementD) == 2 && size<1>(GmemStrideTypeD{}) == 1) {
    if constexpr (size<1>(EpilogueTile_MN{}) % 16 == 0) {
      return SM90_U32x4_STSM_N{};
    }
    else if constexpr (size<1>(EpilogueTile_MN{}) % 8 == 0) {
      return SM90_U32x2_STSM_N{};
    }
  }
  else {
    // auto-vectorizing store
    return AutoVectorizingCopyWithAssumedAlignment{};
  }
}

// Selects the largest vectorized smem load atom available
template <class GmemStrideTypeC, class ElementC, class EpilogueTile_MN>
constexpr auto
sm90_get_smem_load_op_for_source() {
  using namespace cute;

  // Reuse the logic from smem store selector
  using SmemStoreOp = decltype(sm90_get_smem_store_op_for_accumulator<GmemStrideTypeC, ElementC, EpilogueTile_MN>());

  if constexpr (cute::is_same_v<SmemStoreOp, SM90_U16x8_STSM_T>) {
    return SM75_U16x8_LDSM_T{};
  }
  else if constexpr (cute::is_same_v<SmemStoreOp, SM90_U16x4_STSM_T>) {
    return SM75_U16x4_LDSM_T{};
  }
  else if constexpr (cute::is_same_v<SmemStoreOp, SM90_U32x4_STSM_N>) {
    return SM75_U32x4_LDSM_N{};
  }
  else if constexpr (cute::is_same_v<SmemStoreOp, SM90_U32x2_STSM_N>) {
    return SM75_U32x2_LDSM_N{};
  }
  else {
    // auto-vectorizing load
    return AutoVectorizingCopyWithAssumedAlignment<128>{};
  }
}

// C/D should meet TMA alignment requirement if not void
template <class ElementC, int AlignmentC, class ElementD, int AlignmentD>
constexpr bool
is_aligned() {
  return (cute::is_void_v<ElementC> || (cute::sizeof_bits_v<ElementC> * AlignmentC) % cutlass::detail::get_output_alignment_bits<ElementC>() == 0) &&
         (cute::is_void_v<ElementD> || (cute::sizeof_bits_v<ElementD> * AlignmentD) % cutlass::detail::get_output_alignment_bits<ElementD>() == 0);
}

///////////////////////////////////////////////////////////////////////////////

} // namespace cutlass::epilogue::collective::detail
