Source code for simvx.graphics.platform

"""Windowing abstraction — auto-detects available backend."""


from __future__ import annotations

from typing import TYPE_CHECKING

if TYPE_CHECKING:
    from ._base import WindowBackend

__all__ = ["AVAILABLE_BACKENDS", "get_backend", "resolve_backend"]

_BACKENDS: list[tuple[str, str, str]] = [
    ("glfw", "._glfw", "GlfwBackend"),
    ("sdl3", "._sdl3", "Sdl3Backend"),
    ("qt", "._qt", "QtBackend"),
]

AVAILABLE_BACKENDS: tuple[str, ...] = tuple(name for name, _, _ in _BACKENDS)




def resolve_backend(name: str | None = None) -> tuple[WindowBackend, str]:
    """Return a ``(backend, resolved_name)`` pair.

    If *name* is ``None``, tries each backend in order and returns the first
    one whose import succeeds along with its name.
    """
    if name is not None:
        for bname, module, cls in _BACKENDS:
            if bname == name:
                import importlib

                mod = importlib.import_module(module, __package__)
                return getattr(mod, cls)(), bname
        raise ValueError(f"Unknown backend: {name!r}. Allowed: {list(AVAILABLE_BACKENDS)}")

    for bname, module, cls in _BACKENDS:
        try:
            import importlib

            mod = importlib.import_module(module, __package__)
            backend_cls = getattr(mod, cls)
            return backend_cls(), bname
        except (ImportError, ModuleNotFoundError):
            continue

    raise RuntimeError("No windowing backend available. Install glfw, PySDL3, or PySide6.")





def get_backend(name: str | None = None) -> WindowBackend:
    """Return a windowing backend instance. See :func:`resolve_backend`."""
    return resolve_backend(name)[0]