# Copyright 2020,2021 Sony Corporation.
# Copyright 2021 Sony Group Corporation.
#
# 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.

from abc import ABCMeta, abstractmethod

from nnabla_rl.models.model import Model


class Perturbator(Model, metaclass=ABCMeta):
    ''' DeterministicPolicy
    Abstract class for perturbator

    Perturbator generates noise to append to current state's action
    '''

    def __init__(self, scope_name):
        super(Perturbator, self).__init__(scope_name)

    @abstractmethod
    def generate_noise(self, s, a, phi):
        raise NotImplementedError
