"""
Cheap dataclasses module backport

Check out the official documentation to see what this is trying to
achieve:
https://docs.python.org/3/library/dataclasses.html
"""
from __future__ import annotations

import copy
from collections import OrderedDict
from typing import TYPE_CHECKING, Any, Dict, Generator, Tuple

if TYPE_CHECKING:
    from typing_extensions import Self


class DataclsBase:
    _defaults: "OrderedDict[str, Any]"

    def __init__(self, **kwargs: Any) -> None:
        for name, value in self._defaults.items():
            if name in kwargs:
                value = kwargs[name]
            setattr(self, name, copy.copy(value))

    def __iter__(self) -> Generator[Tuple[str, Any], None, None]:
        for name in self.__annotations__:
            yield (name, getattr(self, name))

    def __repr__(self) -> str:
        return "{}({})".format(
            self.__class__.__name__,
            ", ".join(name + "=" + repr(value) for name, value in self),
        )


class DataclsMeta(type):
    def __new__(
        cls, name: str, bases: Tuple[type, ...], prop: Dict[str, Any]
    ) -> Self:
        values: OrderedDict[str, Any] = OrderedDict()
        for member_name in prop["__annotations__"].keys():
            # Check if member has a default value set as class variable
            if member_name in prop:
                # Store default value and remove the class variable
                values[member_name] = prop[member_name]
                del prop[member_name]
            else:
                # Set None as the default value
                values[member_name] = None

        prop["__slots__"] = list(values.keys())
        prop["_defaults"] = values
        bases = (DataclsBase, *bases)
        return super().__new__(cls, name, bases, prop)

    def __prepare__(self, *args: Any, **kwargs: Any) -> OrderedDict[str, Any]:  # type: ignore # this is custom overriden
        return OrderedDict()