"""
Platform detection for backend selection.
"""

import platform
from typing import Literal


def is_apple_silicon() -> bool:
    """
    Check if running on Apple Silicon (arm64 macOS).
    
    Returns:
        True if on Apple Silicon, False otherwise
    """
    return platform.system() == "Darwin" and platform.machine() == "arm64"


def get_backend_type() -> Literal["mlx", "pytorch"]:
    """
    Detect the best backend for the current platform.
    
    Returns:
        "mlx" on Apple Silicon (if MLX is available), "pytorch" otherwise
    """
    if is_apple_silicon():
        try:
            import mlx
            return "mlx"
        except ImportError:
            # MLX not installed, fallback to PyTorch
            return "pytorch"
    return "pytorch"