from __future__ import annotations

import pytest
import torch

from kernels.triton.tiled_matmul import triton_tiled_matmul
from reference.torch_matmul import torch_matmul


def _run_impl_or_skip(fn, *args):
    try:
        return fn(*args)
    except NotImplementedError:
        pytest.skip("implementation is still TODO")
    except RuntimeError as exc:
        pytest.skip(str(exc))


@pytest.mark.reference
def test_tiled_matmul_reference_matches_torch():
    a = torch.randn(8, 16)
    b = torch.randn(16, 12)
    out = torch_matmul(a, b)
    torch.testing.assert_close(out, a @ b)


@pytest.mark.triton_required
@pytest.mark.skeleton
def test_triton_tiled_matmul_if_available():
    if not torch.cuda.is_available():
        pytest.skip("CUDA is not available")
    a = torch.randn(32, 48, device="cuda")
    b = torch.randn(48, 40, device="cuda")
    out = _run_impl_or_skip(triton_tiled_matmul, a, b)
    torch.testing.assert_close(out, a @ b, atol=1e-3, rtol=1e-3)