# vim: tabstop=4 shiftwidth=4 softtabstop=4

# Copyright 2011 Nicira Networks, Inc
# All Rights Reserved.
#
#    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.
# @author: Somik Behera, Nicira Networks, Inc.


"""
Quantum's Manager class is responsible for parsing a config file
and instantiating the correct plugin that concretely implement
quantum_plugin_base class

The caller should make sure that QuantumManager is a singleton.
"""
import gettext
gettext.install('quantum', unicode=1)

from common import utils
from quantum_plugin_base import QuantumPluginBase

CONFIG_FILE = "quantum/plugins.ini"


class QuantumManager(object):

    def __init__(self, config=CONFIG_FILE):
        self.configuration_file = CONFIG_FILE
        plugin_location = utils.getPluginFromConfig(CONFIG_FILE)
        print "PLUGIN LOCATION:%s" % plugin_location
        plugin_klass = utils.import_class(plugin_location)
        if not issubclass(plugin_klass, QuantumPluginBase):
            raise Exception("Configured Quantum plug-in " \
                            "didn't pass compatibility test")
        else:
            print("Successfully imported Quantum plug-in." \
                  "All compatibility tests passed\n")
        self.plugin = plugin_klass()

    def get_manager(self):
        return self.plugin


# TODO(somik): rmove the main class
# Added for temporary testing purposes
def main():
    manager = QuantumManager()
    myManager = manager.get_manager()
    myManager.get_all_networks("tesst")
    #print("is a plugin")

# Standard boilerplate to call the main() function.
if __name__ == '__main__':
    main()