import sys
import socket
import gettext
from urlparse import urlparse
from sfa.util.sfalogging import logger
from sfa.util.config import Config

try:
    from sfa.openstack.client import GlanceClient, NovaClient, KeystoneClient
    has_nova = True
except:
    has_nova = False


class Shell:
    """
    A simple native shell to a nova backend. 
    This class can receive all nova calls to the underlying testbed
    """

    # dont care about limiting calls yet
    direct_calls = []
    alias_calls = {}

    # use the 'capability' auth mechanism for higher performance when the PLC
    # db is local
    def __init__(self, config=None):
        if not config:
            config = Config()
        if has_nova:
            # instantiate managers
            self.auth_manager = KeystoneClient(config=config)
            self.image_manager = GlanceClient(config=config)
            self.nova_manager = NovaClient(config=config)
        else:
            logger.debug('nova access - REST')
            raise SfaNotImplemented('nova access - Rest')