from application.system import host
from sipsimple.account import Account, AccountManager
from sipsimple.configuration import SettingsObject
from sipsimple.configuration.datatypes import SIPAddress
from sipsimple.core import Engine, Route, SIPURI

from sylk.configuration import SIPConfig


__all__ = 'DefaultAccount',


class DefaultContactURIFactory(object):

    def __init__(self):
        self.username = 'sylkserver'

    def __getitem__(self, key):
        if isinstance(key, tuple):
            # The first part of the key might be PublicGRUU and so on, but we don't care about
            # those here, so ignore them
            _, key = key
        if not isinstance(key, (str, Route)):
            raise KeyError("key must be a transport name or Route instance")

        transport = key if isinstance(key, str) else key.transport
        parameters = {} if transport=='udp' else {'transport': transport}
        if SIPConfig.local_ip not in (None, '0.0.0.0'):
            ip = SIPConfig.local_ip.normalized
        elif isinstance(key, str):
            ip = host.default_ip
        else:
            ip = host.outgoing_ip_for(key.address)
        if ip is None:
            raise KeyError("could not get outgoing IP address")
        port = getattr(Engine(), '%s_port' % transport, None)
        if port is None:
            raise KeyError("unsupported transport: %s" % transport)
        uri = SIPURI(user=self.username, host=ip, port=port)
        uri.parameters.update(parameters)
        return uri


class DefaultAccount(Account):
    """
    Subclass of Account which doesn't start any subsystem. SylkServer just
    uses it as the default account for all applications as a settings object.
    """

    __id__ = SIPAddress('default@sylkserver')

    id = property(lambda self: self.__id__)
    enabled = True

    def __new__(cls):
        #with AccountManager.load.lock:
        #    if not AccountManager.load.called:
        #        raise RuntimeError("cannot instantiate %s before calling AccountManager.load" % cls.__name__)
        return SettingsObject.__new__(cls)

    def __init__(self):
        super(DefaultAccount, self).__init__('default@sylkserver')
        self.contact = DefaultContactURIFactory()

    @property
    def uri(self):
        return SIPURI(user='sylkserver', host=SIPConfig.local_ip.normalized)

    def _activate(self):
        pass

    def _deactivate(self):
        pass