#include <migraph/gpu/gemm.hpp>
#include <migraph/operators.hpp>
#include <migraph/manage_ptr.hpp>
#include <migraph/gpu/miopen.hpp>
#include <utility>

namespace migraph {
namespace gpu {

template<class... Ts>
void generic_rocblas_gemm(shape::as<float>, Ts&&... xs)
{
      rocblas_sgemm(std::forward<Ts>(xs)...);
}

template<class... Ts>
void generic_rocblas_gemm(shape::as<double>, Ts&&... xs)
{
      rocblas_dgemm(std::forward<Ts>(xs)...);
}

template<class... Ts>
void generic_rocblas_gemm(shape::as<half>, Ts&&... xs)
{
      rocblas_hgemm(std::forward<Ts>(xs)...);
}

template<class T, class... Ts>
void generic_rocblas_gemm(shape::as<T>, Ts&&...)
{
      MIGRAPH_THROW("Type unsupported by rocblas"); 
}

template<class T>
T to_rocblas_type(T x)
{
  return x;
}

rocblas_half to_rocblas_type(half x)
{
  return reinterpret_cast<const rocblas_half&>(x);
}

shape miopen_gemm::compute_shape(const std::vector<shape>& inputs) const
{
    check_shapes{inputs, *this}.has(3);
    return op.compute_shape({inputs.at(0), inputs.at(1)});
}
argument miopen_gemm::compute(context& ctx,
                              const shape& output_shape,
                              const std::vector<argument>& args) const
{
    float alpha     = 1.0f;
    float beta      = 0.0f;
    bool transa     = args[0].get_shape().transposed();
    bool transb     = args[1].get_shape().transposed();
    rocblas_int lda = args[0].get_shape().strides()[transa ? 1 : 0];
    rocblas_int ldb = args[1].get_shape().strides()[transb ? 1 : 0];
    rocblas_int ldc = args[2].get_shape().strides()[0];
    rocblas_int m   = output_shape.lens()[0];
    rocblas_int n   = output_shape.lens()[1];
    rocblas_int k   = args[0].get_shape().lens()[1];
    output_shape.visit_type([&](auto as) {
      auto alpha_r     = to_rocblas_type(as(alpha));
      auto beta_r      = to_rocblas_type(as(beta));
      generic_rocblas_gemm(as, ctx.get_stream().get_rocblas(),
                    transb ? rocblas_operation_transpose : rocblas_operation_none,
                    transa ? rocblas_operation_transpose : rocblas_operation_none,
                    n,
                    m,
                    k,
                    &alpha_r,
                    args[1].implicit(),
                    ldb,
                    args[0].implicit(),
                    lda,
                    &beta_r,
                    args[2].implicit(),
                    ldc);
        
    });
    return args[2];
}

} // namespace gpu

} // namespace migraph