"""hooks to ensure use_email / primary_email relations consistency

:organization: Logilab

:copyright: 2001-2009 LOGILAB S.A. (Paris, FRANCE), license is LGPL v2.

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

:license: GNU Lesser General Public License, v2.1 - http://www.gnu.org/licenses

"""

__docformat__ = "restructuredtext en"

from cubicweb.server import hook

from cubicweb.server.repository import ensure_card_respected

class SetUseEmailRelationOp(hook.Operation):

    """delay this operation to commit to avoid conflict with a late rql query

    already setting the relation

    """

    rtype = 'use_email'

    entity = email = None # make pylint happy

    def condition(self):

        """check entity has use_email set for the email address"""

        return not any(e for e in self.entity.use_email

                       if self.email.eid == e.eid)

    def precommit_event(self):

        if self.condition():

            # we've to handle cardinaly by ourselves since we're using unsafe_execute

            # but use session.execute and not session.unsafe_execute to check we

            # can change the relation

            ensure_card_respected(session.execute, session,

                                  self.fromeid, self.rtype, self.toeid)

            session.unsafe_execute(

                'SET X %s Y WHERE X eid %%(x)s, Y eid %%(y)s' % self.rtype,

                {'x': self.entity.eid, 'y': self.email.eid}, 'x')

class SetPrimaryEmailRelationOp(SetUseEmailRelationOp):

    rtype = 'primary_email'

    def condition(self):

        """check entity has no primary_email set"""

        return not self.entity.primary_email

class SetPrimaryEmailHook(hook.Hook):

    """notify when a bug or story or version has its state modified"""

    __id__ = 'setprimaryemail'

    __select__ = hook.Hook.__select__ & hook.match_rtype('use_email')

    category = 'email'

    events = ('after_add_relation',)

    def __call__(self):

        entity = self._cw.entity_from_eid(self.eidfrom)

        if 'primary_email' in entity.e_schema.subject_relations():

            SetPrimaryEmailRelationOp(self._cw, entity=entity,

                                      email=self._cw.entity_from_eid(self.eidto))

class SetUseEmailHook(hook.Hook):

    """notify when a bug or story or version has its state modified"""

    __id__ = 'setprimaryemail'

    __select__ = hook.Hook.__select__ & hook.match_rtype('primary_email')

    category = 'email'

    events = ('after_add_relation',)

    def __call__(self):

        entity = self._cw.entity_from_eid(self.eidfrom)

        if 'use_email' in entity.e_schema.subject_relations():

            SetUseEmailRelationOp(self._cw, entity=entity,

                                  email=self._cw.entity_from_eid(self.eidto))