import sys

import clr_loader

_RUNTIME = None

_LOADER_ASSEMBLY = None

_FFI = None

_LOADED = False

def set_runtime(runtime):

global _RUNTIME

if _LOADED:

raise RuntimeError("The runtime {} has already been loaded".format(_RUNTIME))

_RUNTIME = runtime

def set_default_runtime() -> None:

if sys.platform == "win32":

set_runtime(clr_loader.get_netfx())

else:

set_runtime(clr_loader.get_mono())

def load():

global _FFI, _LOADED, _LOADER_ASSEMBLY

if _LOADED:

return

from os.path import join, dirname

if _RUNTIME is None:

# TODO: Warn, in the future the runtime must be set explicitly, either

# as a config/env variable or via set_runtime

set_default_runtime()

dll_path = join(dirname(__file__), "runtime", "Python.Runtime.dll")

_LOADER_ASSEMBLY = _RUNTIME.get_assembly(dll_path)

func = _LOADER_ASSEMBLY["Python.Runtime.Loader.Initialize"]

if func(b"") != 0:

raise RuntimeError("Failed to initialize Python.Runtime.dll")

import atexit

atexit.register(unload)

def unload():

global _RUNTIME

if _LOADER_ASSEMBLY is not None:

func = _LOADER_ASSEMBLY["Python.Runtime.Loader.Shutdown"]

if func(b"full_shutdown") != 0:

raise RuntimeError("Failed to call Python.NET shutdown")

if _RUNTIME is not None:

# TODO: Add explicit `close` to clr_loader

_RUNTIME = None