import collections.abc
from dataclasses import dataclass
from typing import Union, Mapping, Literal, Callable, Tuple, List, Optional

LangTyping = Literal['en', 'cn']
MultiLangCheckerTyping = Callable[[str, str, str], Tuple[bool, Optional[str]]]
SingleLangCheckerTyping = Callable[[str, str], Tuple[bool, Optional[str]]]


@dataclass
class Question:
    texts: Mapping[str, str]
    checker: MultiLangCheckerTyping
    level: int


_KNOWN_PROBLEMS = []


def register_question(text: Union[Mapping[str, str], str],
                      checkers: Union[Mapping[str, SingleLangCheckerTyping], MultiLangCheckerTyping],
                      level: int = 1, default_lang='cn'):
    if isinstance(checkers, collections.abc.Mapping):
        _origin_checkers = checkers

        def _integrated_checker(question_text: str, answer_text: str, lang: str):
            return _origin_checkers[lang](question_text, answer_text)

        checker: MultiLangCheckerTyping = _integrated_checker
    else:
        checker: MultiLangCheckerTyping = checkers

    if isinstance(text, str):
        texts = {default_lang: text}
    else:
        texts = text

    _KNOWN_PROBLEMS.append(Question(texts, checker, level))


def list_ordered_questions() -> List[Question]:
    return [
        problem for _, problem in
        sorted(enumerate(_KNOWN_PROBLEMS), key=lambda x: (x[1].level, x[0]))
    ]