X-Git-Url: http://git.ithinksw.org/philo.git/blobdiff_plain/2f2aed7e371d11b021432124de8f9bdd436b0832..e3037e2cf8a7ad3d0c3dba94083d1753301f581b:/models/fields.py

diff --git a/models/fields.py b/models/fields.py
index 7f76b9c..9fc2dfb 100644
--- a/models/fields.py
+++ b/models/fields.py
@@ -1,54 +1,80 @@
 from django.db import models
-from django.db.models import signals
-from django.core.exceptions import ObjectDoesNotExist, FieldError
-from django.contrib.contenttypes.models import ContentType
-from functools import partial
-from philo.models.base import Attribute, Relationship, Entity
+from django import forms
+from django.core.exceptions import FieldError
+from philo.models.base import Entity
+from philo.signals import entity_class_prepared
 
 
 __all__ = ('AttributeField', 'RelationshipField')
 
 
+class EntityProxyField(object):
+	descriptor_class = None
+	
+	def __init__(self, *args, **kwargs):
+		if self.descriptor_class is None:
+			raise NotImplementedError('EntityProxyField subclasses must specify a descriptor_class.')
+	
+	def actually_contribute_to_class(self, sender, **kwargs):
+		sender._entity_meta.add_proxy_field(self)
+		setattr(sender, self.attname, self.descriptor_class(self))
+	
+	def contribute_to_class(self, cls, name):
+		if issubclass(cls, Entity):
+			self.name = name
+			self.attname = name
+			entity_class_prepared.connect(self.actually_contribute_to_class, sender=cls)
+		else:
+			raise FieldError('%s instances can only be declared on Entity subclasses.' % self.__class__.__name__)
+	
+	def formfield(self, *args, **kwargs):
+		raise NotImplementedError('EntityProxyField subclasses must implement a formfield method.')
+	
+	def value_from_object(self, obj):
+		return getattr(obj, self.attname)
+
+
 class AttributeFieldDescriptor(object):
 	def __init__(self, field):
 		self.field = field
 	
 	def __get__(self, instance, owner):
 		if instance:
+			if self.field.key in instance._added_attribute_registry:
+				return instance._added_attribute_registry[self.field.key]
+			if self.field.key in instance._removed_attribute_registry:
+				return None
 			try:
-				return instance.attribute_set.get(key__exact=self.field.key).value
-			except ObjectDoesNotExist:
+				return instance.attributes[self.field.key]
+			except KeyError:
 				return None
 		else:
 			raise AttributeError('The \'%s\' attribute can only be accessed from %s instances.' % (self.field.name, owner.__name__))
 	
 	def __set__(self, instance, value):
-		try:
-			attribute = instance.attribute_set.get(key__exact=self.field.key)
-		except ObjectDoesNotExist:
-			attribute = Attribute()
-			attribute.entity = instance
-			attribute.key = self.field.key
-		attribute.value = value
-		attribute.save()
+		if self.field.key in instance._removed_attribute_registry:
+			instance._removed_attribute_registry.remove(self.field.key)
+		instance._added_attribute_registry[self.field.key] = value
 	
 	def __delete__(self, instance):
-		instance.attribute_set.filter(key__exact=self.field.key).delete()
+		if self.field.key in instance._added_attribute_registry:
+			del instance._added_attribute_registry[self.field.key]
+		instance._removed_attribute_registry.append(self.field.key)
 
 
-class AttributeField(object):
-	def __init__(self, key):
-		self.key = key
+class AttributeField(EntityProxyField):
+	descriptor_class = AttributeFieldDescriptor
 	
-	def actually_contribute_to_class(self, sender, **kwargs):
-		setattr(sender, self.name, AttributeFieldDescriptor(self))
+	def __init__(self, key, field_template=None):
+		self.key = key
+		if field_template is None:
+			field_template = models.CharField(max_length=255)
+		self.field_template = field_template
 	
-	def contribute_to_class(self, cls, name):
-		if issubclass(cls, Entity):
-			self.name = name
-			signals.class_prepared.connect(self.actually_contribute_to_class, sender=cls)
-		else:
-			raise FieldError('AttributeFields can only be declared on Entity subclasses.')
+	def formfield(self, *args, **kwargs):
+		field = self.field_template.formfield(*args, **kwargs)
+		field.required = False
+		return field
 
 
 class RelationshipFieldDescriptor(object):
@@ -57,40 +83,46 @@ class RelationshipFieldDescriptor(object):
 	
 	def __get__(self, instance, owner):
 		if instance:
+			if self.field.key in instance._added_relationship_registry:
+				return instance._added_relationship_registry[self.field.key]
+			if self.field.key in instance._removed_relationship_registry:
+				return None
 			try:
-				return instance.relationship_set.get(key__exact=self.field.key).value
-			except ObjectDoesNotExist:
+				return instance.relationships[self.field.key]
+			except KeyError:
 				return None
 		else:
 			raise AttributeError('The \'%s\' attribute can only be accessed from %s instances.' % (self.field.name, owner.__name__))
 	
 	def __set__(self, instance, value):
 		if isinstance(value, (models.Model, type(None))):
-			try:
-				relationship = instance.relationship_set.get(key__exact=self.field.key)
-			except ObjectDoesNotExist:
-				relationship = Relationship()
-				relationship.entity = instance
-				relationship.key = self.field.key
-			relationship.value = value
-			relationship.save()
+			if self.field.key in instance._removed_relationship_registry:
+				instance._removed_relationship_registry.remove(self.field.key)
+			instance._added_relationship_registry[self.field.key] = value
 		else:
-			raise AttributeError('The \'%\' attribute can only be set using existing Model objects.' % self.field.name)
+			raise AttributeError('The \'%s\' attribute can only be set using existing Model objects.' % self.field.name)
 	
 	def __delete__(self, instance):
-		instance.relationship_set.filter(key__exact=self.field.key).delete()
+		if self.field.key in instance._added_relationship_registry:
+			del instance._added_relationship_registry[self.field.key]
+		instance._removed_relationship_registry.append(self.field.key)
 
 
-class RelationshipField(object):
-	def __init__(self, key):
+class RelationshipField(EntityProxyField):
+	descriptor_class = RelationshipFieldDescriptor
+	
+	def __init__(self, key, model, limit_choices_to=None):
 		self.key = key
+		self.model = model
+		if limit_choices_to is None:
+			limit_choices_to = {}
+		self.limit_choices_to = limit_choices_to
 	
-	def actually_contribute_to_class(self, sender, **kwargs):
-		setattr(sender, self.name, RelationshipFieldDescriptor(self))
+	def formfield(self, form_class=forms.ModelChoiceField, **kwargs):
+		field = form_class(self.model._default_manager.complex_filter(self.limit_choices_to), **kwargs)
+		field.required = False
+		return field
 	
-	def contribute_to_class(self, cls, name):
-		if issubclass(cls, Entity):
-			self.name = name
-			signals.class_prepared.connect(self.actually_contribute_to_class, sender=cls)
-		else:
-			raise FieldError('RelationshipFields can only be declared on Entity subclasses.')
\ No newline at end of file
+	def value_from_object(self, obj):
+		relobj = super(RelationshipField, self).value_from_object(obj)
+		return getattr(relobj, 'pk', None)
\ No newline at end of file