# Copyright 1999-2021 Alibaba Group Holding Ltd.
#
# 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.
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from abc import ABC, abstractmethod
from typing import Dict, Type

from .context import register_backend_context
from .driver import register_backend_driver


__all__ = ["BaseActorBackend", "register_backend", "get_backend"]


class BaseActorBackend(ABC):
    @staticmethod
    @abstractmethod
    def name():
        pass

    @staticmethod
    @abstractmethod
    def get_context_cls():
        pass

    @classmethod
    async def create_actor_pool(cls, address: str, n_process: int = None, **kwargs):
        pass

    @staticmethod
    @abstractmethod
    def get_driver_cls():
        pass


_scheme_to_backend_cls: Dict[str, Type[BaseActorBackend]] = dict()


def register_backend(backend_cls: Type[BaseActorBackend]):
    _scheme_to_backend_cls[backend_cls.name()] = backend_cls
    register_backend_context(backend_cls.name(), backend_cls.get_context_cls())
    register_backend_driver(backend_cls.name(), backend_cls.get_driver_cls())
    return backend_cls


def get_backend(name):
    return _scheme_to_backend_cls[name]
