# telepathy-python - Base classes defining the interfaces of the Telepathy framework
#
# Copyright (C) 2005 Collabora Limited
# Copyright (C) 2005 Nokia Corporation
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

import dbus
import logging

from dbus import PROPERTIES_IFACE

logger = logging.getLogger('telepathy.client.interfacefactory')

def default_error_handler(exception):
    logging.basicConfig()
    logger.warning('Exception from asynchronous method call:\n%s' % exception)

class InterfaceFactory(object):
    """Base class for an object wrapping the D-Bus interfaces of a Telepathy
    object.

    This object acts like a dict where the keys are D-Bus interface names,
    and the values are `dbus.Interface` objects. In addition, D-Bus methods
    called directly on this object (``interface_factory_subclass.GetFoo()``)
    can be treated like calls to a default interface.
    """

    def __init__(self, dbus_object, default_interface=None):
        """Constructor.

        :Parameters:
            `dbus_object` : dbus.proxies.ProxyObject
                The underlying D-Bus object
            `default_interface` : str
                The D-Bus interface to be used for method calls made
                directly on this object
        """
        #: The underlying `dbus.proxies.ProxyObject`. Read-only attribute.
        #: :Since: 0.13.13.
        self.dbus_proxy = dbus_object

        # backwards compat for people using pre-public API
        # FIXME: remove this in 0.14?
        self._dbus_object = dbus_object

        self._interfaces = {}
        self._valid_interfaces = set()
        # add the D-Bus properties interface
        self._valid_interfaces.add(PROPERTIES_IFACE)
        self._default_interface = default_interface

        if default_interface:
            self._valid_interfaces.add(default_interface)

    def get_valid_interfaces(self):
        return self._valid_interfaces

    def __getitem__(self, name):
        if name not in self._interfaces:
            if name not in self._valid_interfaces:
                raise KeyError(name)

            self._interfaces[name] = dbus.Interface(self._dbus_object, name)

        return self._interfaces[name]

    def __contains__(self, name):
        return name in self._interfaces or name in self._valid_interfaces

    def __getattr__(self, name):
        return getattr(self[self._default_interface], name)