Adds optional use of notes records

Adds use of description, user_id, user_ip from notes table if data-migration is done, otherwise use body, author_id, author_ip from note's first comment. Decision procedure "data-migration is done" is defined with "is user_ip or user_id not nil?".

app/models/note.rb

@@ -89,24 +89,39 @@ def freshly_closed_until
     closed_at + DEFAULT_FRESHLY_CLOSED_LIMIT
   end
 
-  # Return the note's description, derived from the first comment
+  # Return the note's description, unless record is unavailable and
+  # it will be derived from the first comment
   def description
-    comments.first.body
+    if user_ip.nil? && user_id.nil?
+      comments.first.body
+    else
+      RichText.new("text", description)
+    end
   end
 
   # Return the note's author object, derived from the first comment
   def author
     comments.first.author
   end
 
-  # Return the note's author ID, derived from the first comment
+  # Return the note's author ID, unless record is unavailable and
+  # it will be derived from the first comment
   def author_id
-    comments.first.author_id
+    if user_ip.nil? && user_id.nil?
+      comments.first.author_id
+    else
+      user_id
+    end
   end
 
-  # Return the note's author IP address, derived from the first comment
+  # Return the note's author IP address, unless record is unavailable and
+  # it will be derived from the first comment
   def author_ip
-    comments.first.author_ip
+    if user_ip.nil? && user_id.nil?
+      comments.first.author_ip
+    else
+      user_ip
+    end
   end
 
   private