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#
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
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import threading
from typing import Union

from gui_plugin.core.CompletionEvent import CompletionEvent


def get_context() -> Union[threading.local, None]:
    """Getting context of the current thread.

    Returns:
        threading.local | None: context of the current thread or None if no context
    """

    current_thread = threading.current_thread()
    if hasattr(current_thread, "get_context"):
        return current_thread.get_context()

    return None


def set_completion_event() -> Union[CompletionEvent, None]:
    """Creates and adds CompletionEvent to the current thread context.

    Returns:
        CompletionEvent | None: The created CompletionEvent or None if no context
    """
    context = get_context()
    if context:
        context.completion_event = CompletionEvent()
        return context.completion_event

    return None
