X-Git-Url: http://git.ithinksw.org/philo.git/blobdiff_plain/806ef92a88cc844c47e59220ada96477a4ce601a..46fdca9049d4b7806bc4d6ec33973a3fc19153c4:/utils.py

diff --git a/utils.py b/utils.py
index e3d1124..5fc3274 100644
--- a/utils.py
+++ b/utils.py
@@ -1,3 +1,58 @@
+from django.db import models
+from django.contrib.contenttypes.models import ContentType
+
+
+class ContentTypeLimiter(object):
+	def q_object(self):
+		return models.Q(pk__in=[])
+	
+	def add_to_query(self, query, *args, **kwargs):
+		query.add_q(self.q_object(), *args, **kwargs)
+
+
+class ContentTypeRegistryLimiter(ContentTypeLimiter):
+	def __init__(self):
+		self.classes = []
+	
+	def register_class(self, cls):
+		self.classes.append(cls)
+	
+	def unregister_class(self, cls):
+		self.classes.remove(cls)
+	
+	def q_object(self):
+		contenttype_pks = []
+		for cls in self.classes:
+			try:
+				if issubclass(cls, models.Model):
+					if not cls._meta.abstract:
+						contenttype = ContentType.objects.get_for_model(cls)
+						contenttype_pks.append(contenttype.pk)
+			except:
+				pass
+		return models.Q(pk__in=contenttype_pks)
+
+
+class ContentTypeSubclassLimiter(ContentTypeLimiter):
+	def __init__(self, cls, inclusive=False):
+		self.cls = cls
+		self.inclusive = inclusive
+	
+	def q_object(self):
+		contenttype_pks = []
+		for subclass in self.cls.__subclasses__():
+			try:
+				if issubclass(subclass, models.Model):
+					if not subclass._meta.abstract:
+						if not self.inclusive and subclass is self.cls:
+							continue
+						contenttype = ContentType.objects.get_for_model(subclass)
+						contenttype_pks.append(contenttype.pk)
+			except:
+				pass
+		return models.Q(pk__in=contenttype_pks)
+
+
 def fattr(*args, **kwargs):
 	def wrapper(function):
 		for key in kwargs: