# Copyright 2017 Google Inc.
#
# 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.

"""Internal utilities common to all modules."""

import firebase_admin


def _get_initialized_app(app):
    if app is None:
        return firebase_admin.get_app()
    elif isinstance(app, firebase_admin.App):
        initialized_app = firebase_admin.get_app(app.name)
        if app is not initialized_app:
            raise ValueError('Illegal app argument. App instance not '
                             'initialized via the firebase module.')
        return app
    else:
        raise ValueError('Illegal app argument. Argument must be of type '
                         ' firebase_admin.App, but given "{0}".'.format(type(app)))

def get_app_service(app, name, initializer):
    app = _get_initialized_app(app)
    return app._get_service(name, initializer) # pylint: disable=protected-access