1 files changed, 18 insertions, 2 deletions
diff --git a/src/client/elm/Validation.elm b/src/client/elm/Validation.elm
index 1729daa..18b3934 100644
--- a/src/client/elm/Validation.elm
+++ b/src/client/elm/Validation.elm
@@ -1,14 +1,18 @@
 module Validation exposing
   ( date
+  , category
   )
 
-import String exposing (toInt, split)
 import Date exposing (Date)
-import Date.Extra.Create exposing (dateFromFields)
 import Date.Extra.Core exposing (intToMonth)
+import Date.Extra.Create exposing (dateFromFields)
+import Dict
+import String exposing (toInt, split)
 
 import Form.Validate as Validate exposing (..)
 
+import Model.Category exposing (Categories, CategoryId)
+
 date : Validation String Date
 date =
   customValidation string (\str ->
@@ -20,3 +24,15 @@ date =
           _ -> Err (customError "InvalidDate")
       _ -> Err (customError "InvalidDate")
   )
+
+category : Categories -> Validation String CategoryId
+category categories =
+  customValidation string (\str ->
+    case toInt str of
+      Ok category ->
+        if List.member category (Dict.keys categories)
+          then Ok category
+          else Err (customError "InvalidCategory")
+      Err _ ->
+        Err (customError "InvalidCategory")
+  )