import logging

from gettext import gettext as _

from landscape.ui.constants import NOT_MANAGED, CANONICAL_MANAGED

from landscape.ui.model.registration.proxy import RegistrationProxy
from landscape.ui.model.configuration.state import StateError


class ConfigControllerLockError(Exception):
pass


class ConfigController(object):
"""
L{ConfigContoller} defines actions to take against a configuration object,
providing starting values from the file, allowing them to be changed
transiently, reverted or committed.
"""

DEFAULT_DEDICATED_ACCOUNT_NAME = "standalone"

def __init__(self, configuration):
self._observers = []
self._configuration = configuration
self._initialised = True

def __getattr__(self, name):
if name in self.__dict__:
return self.__dict__[name]
else:
return getattr(self._configuration, name)

def __setattr__(self, name, value):
# this test allows attributes to be set in the __init__ method
if not '_initialised' in self.__dict__:
return object.__setattr__(self, name, value)
if name in ConfigController.__dict__:
return object.__setattr__(self, name, value)
else:
try:
setattr(self._configuration, name, value)
self._configuration.modify()
except AttributeError:
return object.__setattr__(self, name, value)
else:
self._configuration.modify()

def load(self):
"""
Load the initial data from the configuration.
"""
return self._configuration.load_data()

def revert(self):
"""
Revert settings to those the configuration object originally found.
"""
try:
self._configuration.revert()
except StateError:
# We probably don't care.
logging.info("landscape-client-settings-ui reverted with no "
"changes to revert.")

def persist(self, on_notify, on_error, on_succeed, on_fail):
"""Persist settings via the configuration object."""
try:
self._configuration.persist()
except StateError:
# We probably don't care.
logging.info("landscape-client-settings-ui committed with no "
"changes to commit.")
if self._configuration.management_type == NOT_MANAGED:
self.disable(on_notify, on_succeed, on_fail)
else:
self.register(on_notify, on_error, on_succeed, on_fail)

def register(self, notify_method, error_method, succeed_method,
fail_method):
"""
Perform registration using the L{RegistrationProxy}.
"""

def registration_fail_wrapper():
fail_method(action=_("Registering client failed"))

def registration_succeed_wrapper():
succeed_method(action=_("Registering client was successful"))

registration = RegistrationProxy(
on_register_notify=notify_method,
on_register_error=error_method,
on_register_succeed=registration_succeed_wrapper,
on_register_fail=registration_fail_wrapper)
if self._configuration.management_type == CANONICAL_MANAGED:
notify_method(_("Attempting to register at %s") %
self._configuration.hosted_landscape_host)
else:
notify_method(_("Attempting to register at %s") %
self._configuration.local_landscape_host)
registration.register(self._configuration.get_config_filename())
registration.exit()

def disable(self, notify_method, succeed_method, fail_method):
"""
Disable landscape client via the L{RegistrationProxy}.
"""

def disabling_fail_wrapper():
fail_method(action=_("Disabling client failed"))

def disabling_succeed_wrapper():
succeed_method(action=_("Disabling client was successful"))

registration = RegistrationProxy(
on_disable_succeed=disabling_succeed_wrapper,
on_disable_fail=disabling_fail_wrapper)
notify_method(_("Attempting to disable landscape client."))
registration.disable()
registration.exit()