--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hooks/email.py	Fri Aug 14 11:14:10 2009 +0200
@@ -0,0 +1,62 @@
+"""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
+
+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():
+            self.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, session, eidfrom, rtype, eidto):
+        entity = self.cw_req.entity_from_eid(self.eidfrom)
+        if 'primary_email' in entity.e_schema.subject_relations():
+            SetPrimaryEmailRelationOp(self.cw_req, entity=entity,
+                                      email=self.cw_req.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_req.entity_from_eid(self.eidfrom)
+        if 'use_email' in entity.e_schema.subject_relations():
+            SetUseEmailRelationOp(self.cw_req, entity=entity,
+                                  email=self.cw_req.entity_from_eid(self.eidto))