from __future__ import annotations

import os
from collections.abc import Callable
from typing import Any


def gpu_task(duration: int = 120, *, always: bool = False):
    """Use ZeroGPU on Spaces and remain a no-op during local development."""

    def decorate(function: Callable[..., Any]):
        if not always and os.getenv("GUARD_BACKEND", "mock").lower() != "gemma":
            return function
        try:
            import spaces
        except ImportError:
            return function
        return spaces.GPU(duration=duration)(function)

    return decorate