Merge branch 'master' of git://github.com/melinath/philo
[philo.git] / models / base.py
index 87914be..2a94daa 100644 (file)
@@ -4,6 +4,7 @@ from django.contrib.contenttypes import generic
 from django.utils import simplejson as json
 from django.core.exceptions import ObjectDoesNotExist
 from philo.utils import ContentTypeRegistryLimiter
+from philo.signals import entity_class_prepared
 from UserDict import DictMixin
 
 
@@ -72,8 +73,8 @@ class Relationship(models.Model):
        entity_object_id = models.PositiveIntegerField(verbose_name='Entity ID')
        entity = generic.GenericForeignKey('entity_content_type', 'entity_object_id')
        key = models.CharField(max_length=255)
-       value_content_type = models.ForeignKey(ContentType, related_name='relationship_value_set', limit_choices_to=value_content_type_limiter, verbose_name='Value type')
-       value_object_id = models.PositiveIntegerField(verbose_name='Value ID')
+       value_content_type = models.ForeignKey(ContentType, related_name='relationship_value_set', limit_choices_to=value_content_type_limiter, verbose_name='Value type', null=True, blank=True)
+       value_object_id = models.PositiveIntegerField(verbose_name='Value ID', null=True, blank=True)
        value = generic.GenericForeignKey('value_content_type', 'value_object_id')
        
        def __unicode__(self):
@@ -104,7 +105,30 @@ class QuerySetMapper(object, DictMixin):
                return list(keys)
 
 
+class EntityOptions(object):
+       def __init__(self, options):
+               if options is not None:
+                       for key, value in options.__dict__.items():
+                               setattr(self, key, value)
+               if not hasattr(self, 'proxy_fields'):
+                       self.proxy_fields = []
+       
+       def add_proxy_field(self, proxy_field):
+               self.proxy_fields.append(proxy_field)
+
+
+class EntityBase(models.base.ModelBase):
+       def __new__(cls, name, bases, attrs):
+               new = super(EntityBase, cls).__new__(cls, name, bases, attrs)
+               entity_options = attrs.pop('EntityMeta', None)
+               setattr(new, '_entity_meta', EntityOptions(entity_options))
+               entity_class_prepared.send(sender=new)
+               return new
+
+
 class Entity(models.Model):
+       __metaclass__ = EntityBase
+       
        attribute_set = generic.GenericRelation(Attribute, content_type_field='entity_content_type', object_id_field='entity_object_id')
        relationship_set = generic.GenericRelation(Relationship, content_type_field='entity_content_type', object_id_field='entity_object_id')
        
@@ -116,6 +140,63 @@ class Entity(models.Model):
        def relationships(self):
                return QuerySetMapper(self.relationship_set)
        
+       @property
+       def _added_attribute_registry(self):
+               if not hasattr(self, '_real_added_attribute_registry'):
+                       self._real_added_attribute_registry = {}
+               return self._real_added_attribute_registry
+       
+       @property
+       def _removed_attribute_registry(self):
+               if not hasattr(self, '_real_removed_attribute_registry'):
+                       self._real_removed_attribute_registry = []
+               return self._real_removed_attribute_registry
+       
+       @property
+       def _added_relationship_registry(self):
+               if not hasattr(self, '_real_added_relationship_registry'):
+                       self._real_added_relationship_registry = {}
+               return self._real_added_relationship_registry
+       
+       @property
+       def _removed_relationship_registry(self):
+               if not hasattr(self, '_real_removed_relationship_registry'):
+                       self._real_removed_relationship_registry = []
+               return self._real_removed_relationship_registry
+       
+       def save(self, *args, **kwargs):
+               super(Entity, self).save(*args, **kwargs)
+               
+               for key in self._removed_attribute_registry:
+                       self.attribute_set.filter(key__exact=key).delete()
+               del self._removed_attribute_registry[:]
+               
+               for key, value in self._added_attribute_registry.items():
+                       try:
+                               attribute = self.attribute_set.get(key__exact=key)
+                       except Attribute.DoesNotExist:
+                               attribute = Attribute()
+                               attribute.entity = self
+                               attribute.key = key
+                       attribute.value = value
+                       attribute.save()
+               self._added_attribute_registry.clear()
+               
+               for key in self._removed_relationship_registry:
+                       self.relationship_set.filter(key__exact=key).delete()
+               del self._removed_relationship_registry[:]
+               
+               for key, value in self._added_relationship_registry.items():
+                       try:
+                               relationship = self.relationship_set.get(key__exact=key)
+                       except Relationship.DoesNotExist:
+                               relationship = Relationship()
+                               relationship.entity = self
+                               relationship.key = key
+                       relationship.value = value
+                       relationship.save()
+               self._added_relationship_registry.clear()
+       
        class Meta:
                abstract = True