#     Copyright 2023, Kay Hayen, mailto:kay.hayen@gmail.com
#
#     Part of "Nuitka", an optimizing Python compiler that is compatible and
#     integrates with CPython, but also works on its own.
#
#     Licensed under the Apache License, Version 2.0 (the "License");
#     you may not use this file except in compliance with the License.
#     You may obtain a copy of the License at
#
#        http://www.apache.org/licenses/LICENSE-2.0
#
#     Unless required by applicable law or agreed to in writing, software
#     distributed under the License is distributed on an "AS IS" BASIS,
#     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#     See the License for the specific language governing permissions and
#     limitations under the License.
#
""" Helper for portable metaclasses that do checks. """

from abc import ABCMeta

from nuitka.Errors import NuitkaNodeDesignError


def getMetaClassBase(meta_class_prefix, require_slots):
    """For Python2/3 compatible source, we create a base class that has the metaclass
    used and doesn't require making a syntax choice.

    Also this allows to enforce the proper usage of "__slots__" for all classes using
    it optionally.
    """

    class MetaClass(ABCMeta):
        def __new__(
            mcs, name, bases, dictionary
        ):  # pylint: disable=I0021,arguments-differ
            if require_slots:
                for base in bases:
                    if base is not object and "__slots__" not in base.__dict__:
                        raise NuitkaNodeDesignError(
                            name, "All bases must set __slots__.", base
                        )

                if "__slots__" not in dictionary:
                    raise NuitkaNodeDesignError(name, "Class must set __slots__.", name)

            return ABCMeta.__new__(mcs, name, bases, dictionary)

    MetaClassBase = MetaClass(
        "%sMetaClassBase" % meta_class_prefix,
        (object,),
        {"__slots__": ()} if require_slots else {},
    )

    return MetaClassBase
