# Copyright 2019 Canonical 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.
# See the License for the specific language governing permissions and
# limitations under the License.

from ros2cli.plugin_system import PLUGIN_SYSTEM_VERSION
from ros2cli.plugin_system import satisfies_version


class VerbExtension:
    """
    The extension point for 'plugin' verb extensions.

    The following properties must be defined:
    * `NAME` (will be set to the entry point name)

    The following methods must be defined:
    * `main`

    The following methods can be defined:
    * `add_arguments`
    """

    NAME = None
    EXTENSION_POINT_VERSION = '0.1'

    def __init__(self):
        super(VerbExtension, self).__init__()
        satisfies_version(PLUGIN_SYSTEM_VERSION, '^0.1')

    def add_arguments(self, parser, cli_name):
        pass

    def main(self, *, args):
        raise NotImplementedError()
