from typing import Tuple


class RequiredAnnotationsMeta(type):
    """Metaclass to save all annotated public class attributes names in _required_attrs_names attribute."""

    def __init__(cls, name, bases, attr_dict):
        super().__init__(name, bases, attr_dict)
        required = set()
        for base_cls in bases:
            required.update(getattr(base_cls, "_required_attrs_names", set()).copy())
        required.update({name for name in getattr(cls, "__annotations__", {}).keys() if not name.startswith('_')})
        cls._required_attrs_names = required


class RequiredAnnotations(metaclass=RequiredAnnotationsMeta):
    """Base class for classes with required annotated attributes.

    Considers all annotated class attributes as required and checks during initialization process
    that all of them were set.

    Example:
        class Example1(RequiredAnnotations):
            a: int
            b: int

        class Example2(Example1):
            a = 1
            c = 3

        inst = Example2()
        AttributeError: Attributes {'b'} of class Example2 were announced as required but haven't been set.
    """

    def __init__(self):
        super().__init__()
        diff = self._required_attrs_names.copy() - set(dir(self))
        if diff:
            raise AttributeError(f"Attributes {diff} of class {self.__class__.__name__} were announced "
                                 f"as required but haven't been set.")


class LoopRunningConfig(RequiredAnnotations):
    """Configuration class for the loop decorator.

    Attributes:
        APP_NAME: string name of running service.
        EXECUTION_TIME_DELAYS: running settings presented as tuple of tuple containing pairs of int values (seconds):
        execution_time_limit, delay. After processing an iteration the decorator measures its execution time and if
        this time <= "execution_time_limit", it makes delay equal "delay" from the same tuple.
    """
    APP_NAME: str
    EXECUTION_TIME_DELAYS: Tuple[Tuple[int, int]] = (
        (0, 30), (90, 60), (180, 90), (300, 120), (600, 300)
    )


class LockConfig(RequiredAnnotations):
    """Configuration class for Lock decorator.

    Attributes:
        APP_NAME: string name of running service.
        REDIS_LOCK_ENABLED: flag of using distributed redis locks to prevent parallel instances execution.
        REDIS_LOCK_TTL: int ttl for distributed lock.

    """
    APP_NAME: str
    REDIS_LOCK_ENABLED: bool
    REDIS_LOCK_TTL: int