Add nested documents to proposal form.

app/helpers/documents_helper.rb

@@ -1,7 +1,7 @@
 module DocumentsHelper
 
   def document_attachment_file_name(document)
-    document.attachment_file_name if document.attachment.exists?
+    document.attachment_file_name
   end
 
   def errors_on_attachment(document)
@@ -22,4 +22,18 @@ module DocumentsHelper
     bytes / Numeric::MEGABYTE
   end
 
+  def document_nested_field_name(document, index, field)
+    parent = document.documentable_type.constantize.name.downcase
+    "#{parent}[documents_attributes][#{index}][#{field}]"
+  end
+
+  def document_nested_field_id(document, index, field)
+    parent = document.documentable_type.constantize.name.downcase
+    "#{parent}_documents_attributes_#{index}_#{field}"
+  end
+
+  def document_nested_field_wrapper_id(index)
+    "document_#{index}"
+  end
+
 end