From 21fb038d0febea5deddf5facd30b2effd05fb702 Mon Sep 17 00:00:00 2001
From: Jan Schrewe <jan@schafproductions.com>
Date: Thu, 21 Nov 2013 14:37:17 +0100
Subject: [PATCH] Make sure not to use LazyDocumentMetaWrapper as doc's meta
 for #61

---
 mongodbforms/documentoptions.py | 41 +++++++++++++++++++++++----------
 mongodbforms/documents.py       | 36 ++++++++++++++---------------
 2 files changed, 47 insertions(+), 30 deletions(-)

diff --git a/mongodbforms/documentoptions.py b/mongodbforms/documentoptions.py
index f1c2146..efbabf9 100644
--- a/mongodbforms/documentoptions.py
+++ b/mongodbforms/documentoptions.py
@@ -44,6 +44,9 @@ def to(self, value):
 
 
 class PkWrapper(object):
+    editable = False
+    fake = False
+    
     def __init__(self, wrapped):
         self.obj = wrapped
 
@@ -118,6 +121,8 @@ class DocumentMetaWrapper(MutableMapping):
     _meta = None
     concrete_model = None
     concrete_managers = []
+    virtual_fields = []
+    auto_created = False
 
     def __init__(self, document, meta=None):
         super(DocumentMetaWrapper, self).__init__()
@@ -127,9 +132,10 @@ def __init__(self, document, meta=None):
         # here for now always the document
         self.concrete_model = document
         if meta is None:
-            self._meta = getattr(document, '_meta', {})
-        else:
-            self._meta = meta
+            meta = getattr(document, '_meta', {})
+            if isinstance(meta, LazyDocumentMetaWrapper):
+                meta = meta._meta
+        self._meta = meta
 
         try:
             self.object_name = self.document.__name__
@@ -143,9 +149,9 @@ def __init__(self, document, meta=None):
         self._setup_document_fields()
         # Setup self.pk if the document has an id_field in it's meta
         # if it doesn't have one it's an embedded document
-        if 'id_field' in self._meta:
-            self.pk_name = self._meta['id_field']
-            self._init_pk()
+        #if 'id_field' in self._meta:
+        #    self.pk_name = self._meta['id_field']
+        self._init_pk()
 
     def _setup_document_fields(self):
         for f in self.document._fields.values():
@@ -183,16 +189,27 @@ def _init_pk(self):
 
         The function also adds a _get_pk_val method to the document.
         """
-        pk_field = getattr(self.document, self.pk_name)
+        if 'id_field' in self._meta:
+            self.pk_name = self._meta['id_field']
+            pk_field = getattr(self.document, self.pk_name)
+        else:
+            pk_field = None
         self.pk = PkWrapper(pk_field)
-        self.pk.name = self.pk_name
-        self.pk.attname = self.pk_name
-
-        self.document._pk_val = pk_field
 
         def _get_pk_val(self):
             return self._pk_val
-        patch_document(_get_pk_val, self.document)
+        
+        if pk_field is not None:
+            self.pk.name = self.pk_name
+            self.pk.attname = self.pk_name
+            self.document._pk_val = pk_field
+            patch_document(_get_pk_val, self.document)
+        else:
+            self.pk.fake = True
+            # this is used in the admin and used to determine if the admin
+            # needs to add a hidden pk field. It does not for embedded fields.
+            # So we pretend to have an editable pk field and just ignore it otherwise
+            self.pk.editable = True
     
     @property
     def app_label(self):
diff --git a/mongodbforms/documents.py b/mongodbforms/documents.py
index aa53846..8c66c07 100644
--- a/mongodbforms/documents.py
+++ b/mongodbforms/documents.py
@@ -832,7 +832,13 @@ def inlineformset_factory(document, form=DocumentForm,
 class EmbeddedDocumentFormSet(BaseDocumentFormSet):
     def __init__(self, data=None, files=None, save_as_new=False,
                  prefix=None, queryset=[], parent_document=None, **kwargs):
-        self.parent_document = parent_document
+        if parent_document is not None:
+            self.parent_document = parent_document
+            
+        if 'instance' in kwargs:
+            instance = kwargs.pop('instance')
+            if parent_document is None:
+                self.parent_document = instance
         
         queryset = getattr(self.parent_document,
                            self.form._meta.embedded_field)
@@ -848,7 +854,8 @@ def _construct_form(self, i, **kwargs):
         # a huge amount of time iterating over the list field on form __init__
         emb_list = getattr(self.parent_document,
                            self.form._meta.embedded_field)
-        if emb_list is not None and len(emb_list) < i:
+                           
+        if emb_list is not None and len(emb_list) > i:
             defaults['position'] = i
         defaults.update(kwargs)
         
@@ -878,22 +885,15 @@ def save(self, commit=True):
         objs = objs or []
         
         if commit and self.parent_document is not None:
-            # The thing about formsets is that the base use case is to edit
-            # *all* of the associated objects on a model. As written, using
-            # these FormSets this way will cause the existing embedded
-            # documents to get saved along with a copy of themselves plus any
-            # new ones you added.
-            #
-            # The only way you could do "updates" of existing embedded document
-            # fields is if those embedded documents had ObjectIDs of their own,
-            # which they don't by default in Mongoengine.
-            #
-            # In this case it makes the most sense to simply replace the
-            # embedded field with the new values gathered form the formset,
-            # rather than adding the new values to the existing values, because
-            # the new values will almost always contain the old values (with
-            # the default use case.)
-            setattr(self.parent_document, self.form._meta.embedded_field, objs)
+            field = self.parent_document._fields.get(self.form._meta.embedded_field, None)
+            if isinstance(field, EmbeddedDocumentField):
+                try:
+                    obj = objs[0]
+                except IndexError:
+                    obj = None
+                setattr(self.parent_document, self.form._meta.embedded_field, obj)
+            else:
+                setattr(self.parent_document, self.form._meta.embedded_field, objs)
             self.parent_document.save()
         
         return objs