From 117d8b194cbd6fe37794c4d94d7a99d6b3aac237 Mon Sep 17 00:00:00 2001
From: Helmut Merz <helmutm@cy55.de>
Date: Tue, 27 Dec 2011 20:10:20 +0100
Subject: [PATCH] backport changes from BlueBream version, e.g. for dynamic
 retrieving renderer; provide context and request for field instance in order
 to work with vocabularies depending on context

---
 composer/schema/field.py      | 24 +++++++++++++++++-------
 composer/schema/grid/field.py |  2 ++
 composer/schema/instance.py   |  3 ++-
 composer/schema/interfaces.py | 12 +++++++++---
 4 files changed, 30 insertions(+), 11 deletions(-)

diff --git a/composer/schema/field.py b/composer/schema/field.py
index 3509b7b..dc89e92 100644
--- a/composer/schema/field.py
+++ b/composer/schema/field.py
@@ -18,8 +18,6 @@
 
 """
 Schema fields and related classes.
-
-$Id$
 """
 
 from datetime import datetime
@@ -32,7 +30,7 @@ from zope.component import adapts
 from zope import component
 from zope.i18n.format import DateTimeParseError
 from zope.i18n.locales import locales
-from zope.schema.interfaces import IVocabularyFactory
+from zope.schema.interfaces import IVocabularyFactory, IContextSourceBinder
 from zope.tales.engine import Engine
 from zope.tales.tales import Context
 
@@ -139,8 +137,15 @@ class Field(Component):
                 return terms
             voc = voc.splitlines()
             return [dict(token=t, title=t) for t in voc if t.strip()]
-        else:
-            return [dict(token=t.token, title=t.title or t.value) for t in voc]
+        elif IContextSourceBinder.providedBy(voc):
+            source = voc(context)
+            terms = component.queryMultiAdapter((source, request), ITerms)
+            if terms is not None:
+                termsList = [terms.getTerm(value) for value in source]
+                return [dict(token=t.token, title=t.title) for t in termsList]
+            else:
+                return None
+        return [dict(token=t.token, title=t.title or t.value) for t in voc]
 
     def getVocabularyTerms(self, name, context, request):
         if context is None or request is None:
@@ -157,12 +162,14 @@ class Field(Component):
     def getFieldTypeInfo(self):
         return self.fieldTypeInfo or fieldTypes.getTerm(self.fieldType)
 
-    def getFieldInstance(self, clientInstance=None):
+    def getFieldInstance(self, clientInstance=None, context=None, request=None):
         instanceName = self.instance_name or self.getFieldTypeInfo().instanceName
         fi = component.queryAdapter(self, IFieldInstance, name=instanceName)
         if fi is None:
             fi = component.getAdapter(self, IFieldInstance, name='')
         fi.clientInstance = clientInstance
+        fi.clientContext = context
+        fi.request = request
         return fi
 
     def getContextProperties(self):
@@ -216,6 +223,9 @@ class FieldInstance(object):
         self.errors.append(error)
         self.severity = max(error.severity, self.severity)
 
+    def getRenderer(self, name):
+        return None
+
 
 class NumberFieldInstance(FieldInstance):
 
@@ -385,7 +395,7 @@ class CheckBoxesFieldInstance(ListFieldInstance):
 class DropdownFieldInstance(FieldInstance):
 
     def display(self, value):
-        items = self.context.getVocabularyItems()
+        items = self.context.getVocabularyItems(self.clientContext, self.request)
         for item in items:
             if item['token'] == value:
                 return item['title']
diff --git a/composer/schema/grid/field.py b/composer/schema/grid/field.py
index e5c8152..b2eefc9 100644
--- a/composer/schema/grid/field.py
+++ b/composer/schema/grid/field.py
@@ -162,6 +162,8 @@ class KeyTableFieldInstance(RecordsFieldInstance):
     def display(self, value):
         headers = [fi.context.title for fi in self.columnFieldInstances]
         rows = []
+        if value is None:
+            value = {}
         for k, v in value.items():
             row = [k]
             for idx, fi in enumerate(self.columnFieldInstances[1:]):
diff --git a/composer/schema/instance.py b/composer/schema/instance.py
index 682898f..1c5ffbf 100644
--- a/composer/schema/instance.py
+++ b/composer/schema/instance.py
@@ -52,7 +52,8 @@ class Instance(BaseInstance):
                 if not f.storeData:
                     # a dummy field, e.g. a spacer
                     continue
-                fi = f.getFieldInstance(self)
+                fi = f.getFieldInstance(self, context=kw.get('context'),
+                                              request=kw.get('request'))
                 name = f.name
                 value = getattr(self.context, name) or fi.default
                 if mode in ('view', 'preview'):
diff --git a/composer/schema/interfaces.py b/composer/schema/interfaces.py
index 6ed3551..9e3f809 100644
--- a/composer/schema/interfaces.py
+++ b/composer/schema/interfaces.py
@@ -1,5 +1,5 @@
 #
-#  Copyright (c) 2010 Helmut Merz helmutm@cy55.de
+#  Copyright (c) 2011 Helmut Merz helmutm@cy55.de
 #
 #  This program is free software; you can redistribute it and/or modify
 #  it under the terms of the GNU General Public License as published by
@@ -18,8 +18,6 @@
 
 """
 Schemas and Fields.
-
-$Id$
 """
 
 from zope import schema
@@ -278,6 +276,14 @@ class IFieldInstance(Interface):
             allow for checking more than one data element.
         """
 
+    def getRenderer(name):
+        """ Return the renderer object (e.g. a ZPT macro) for this field
+            with the name given.
+
+            May return None in which case the calling application should
+            use a default renderer.
+        """
+
 
 class IFormState(Interface):
     """ Represents the state of all fields when editing.