# copyright 2003-2016 LOGILAB S.A. (Paris, FRANCE), all rights reserved.

# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr

#

# This file is part of CubicWeb.

#

# CubicWeb 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.

#

# CubicWeb 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 CubicWeb.  If not, see <http://www.gnu.org/licenses/>.

"""entity classes user and group entities"""

from logilab.common.decorators import cached

from cubicweb import Unauthorized

from cubicweb.entities import AnyEntity, fetch_config

def user_session_cache_key(user_eid, data_name):

    return '{0}-{1}'.format(user_eid, data_name)

class CWGroup(AnyEntity):

    __regid__ = 'CWGroup'

    fetch_attrs, cw_fetch_order = fetch_config(['name'])

    cw_fetch_unrelated_order = cw_fetch_order

    def dc_long_title(self):

        name = self.name

        trname = self._cw._(name)

        if trname != name:

            return '%s (%s)' % (name, trname)

        return name

    @cached

    def num_users(self):

        """return the number of users in this group"""

        return self._cw.execute('Any COUNT(U) WHERE U in_group G, G eid %(g)s',

                                {'g': self.eid})[0][0]

class CWUser(AnyEntity):

    __regid__ = 'CWUser'

    fetch_attrs, cw_fetch_order = fetch_config(['login', 'firstname', 'surname'])

    cw_fetch_unrelated_order = cw_fetch_order

    # used by repository to check if  the user can log in or not

    AUTHENTICABLE_STATES = ('activated',)

    # low level utilities #####################################################

    @property

    def groups(self):

        key = user_session_cache_key(self.eid, 'groups')

        try:

            return self._cw.transaction_data[key]

        except KeyError:

            with self._cw.security_enabled(read=False):

                groups = set(group for group, in self._cw.execute(

                    'Any GN WHERE U in_group G, G name GN, U eid %(userid)s',

                    {'userid': self.eid}))

            self._cw.transaction_data[key] = groups

            return groups

    @property

    def properties(self):

        key = user_session_cache_key(self.eid, 'properties')

        try:

            return self._cw.transaction_data[key]

        except KeyError:

            with self._cw.security_enabled(read=False):

                properties = dict(self._cw.execute(

                    'Any K, V WHERE P for_user U, U eid %(userid)s, '

                    'P pkey K, P value V', {'userid': self.eid}))

            self._cw.transaction_data[key] = properties

            return properties

    def prefered_language(self, language=None):

        """return language used by this user, if explicitly defined (eg not

        using http negociation)

        """

        language = language or self.property_value('ui.language')

        vreg = self._cw.vreg

        try:

            vreg.config.translations[language]

        except KeyError:

            language = vreg.property_value('ui.language')

            assert language in vreg.config.translations[language], language

        return language

    def property_value(self, key):

        try:

            # properties stored on the user aren't correctly typed

            # (e.g. all values are unicode string)

            return self._cw.vreg.typed_value(key, self.properties[key])

        except KeyError:

            pass

        except ValueError:

            self.warning('incorrect value for eproperty %s of user %s',

                         key, self.login)

        return self._cw.vreg.property_value(key)

    def set_property(self, pkey, value):

        try:

            prop = self._cw.execute(

                'CWProperty X WHERE X pkey %(k)s, X for_user U, U eid %(u)s',

                {'k': pkey, 'u': self.eid}).get_entity(0, 0)

        except Exception:

            kwargs = dict(pkey=pkey, value=value)

            if self.is_in_group('managers'):

                kwargs['for_user'] = self

            self._cw.create_entity('CWProperty', **kwargs)

        else:

            prop.cw_set(value=value)

    def matching_groups(self, groups):

        """return the number of the given group(s) in which the user is

        :type groups: str or iterable(str)

        :param groups: a group name or an iterable on group names

        """

        if isinstance(groups, str):

            groups = frozenset((groups,))

        elif isinstance(groups, (tuple, list)):

            groups = frozenset(groups)

        return len(groups & self.groups)  # XXX return the resulting set instead of its size

    def is_in_group(self, group):

        """convience / shortcut method to test if the user belongs to `group`

        """

        return group in self.groups

    def is_anonymous(self):

        """ checks if user is an anonymous user"""

        # FIXME on the web-side anonymous user is detected according to config['anonymous-user'],

        # we don't have this info on the server side.

        return self.groups == frozenset(('guests', ))

    def owns(self, eid):

        try:

            return self._cw.execute(

                'Any X WHERE X eid %(x)s, X owned_by U, U eid %(u)s',

                {'x': eid, 'u': self.eid})

        except Unauthorized:

            return False

    owns = cached(owns, keyarg=1)

    # presentation utilities ##################################################

    def name(self):

        """construct a name using firstname / surname or login if not defined"""

        if self.firstname and self.surname:

            return self._cw._('%(firstname)s %(surname)s') % {

                'firstname': self.firstname, 'surname': self.surname}

        if self.firstname:

            return self.firstname

        return self.login

    def dc_title(self):

        return self.login

    dc_long_title = name