import multiprocessing
from typing import Any, Callable, Iterator


class TimeoutException(Exception):
    pass

def get_tests_for(cls: type) -> Iterator[Callable[[], None]]:
    """get all functions that are declared as tests"""
    return [e for e in cls.__dict__.values() if hasattr(e, 'is_test')]

def test_wrapper(test: Callable[[], None]):
    try:
        test()
    except Exception as e:
        test.has_failed = True
        test.cause = e
    

def run_test(test: Callable[[], None]) -> None:
    """run a test and catch any unexpected behavior and mark it as failed with the exception as cause"""
    if not hasattr(test, 'is_test'):
        return
    timeout = test.timeout
    p = multiprocessing.Process(target=test_wrapper, args=[test])
    p.start()
    p.join(timeout)
    if p.is_alive():
        test.has_failed = True
        test.cause = TimeoutException(f"test failed after {timeout} seconds")


def run_tests_for_task(task: object) -> None:
    for test in task.tests:
        run_test(test)


def eip_task(name: str, max_points: float) -> Callable[[type], type]:
    def wrapper(cls: type) -> type:
        cls.is_task: bool = True
        cls.name: str = name
        cls.max_points: float = max_points
        cls.tests: Callable[..., None] = get_tests_for(cls)
        return cls
    return wrapper


def eip_test(msg: str, points: float, timeout = 180) -> Callable[[], None]:
    def wrapper(test: Callable[[], None]) -> Callable[[], None]:
        test.is_test: bool = True
        test.msg: str = msg
        test.has_failed: bool = False
        test.points: float = points
        test.timeout: int = timeout
        test.cause: Any | None = None
        return test
    return wrapper