1 files changed, 21 insertions, 4 deletions
diff --git a/src/client/Model/PaymentCategory.elm b/src/client/Model/PaymentCategory.elm
index bb6c152..a4fceb1 100644
--- a/src/client/Model/PaymentCategory.elm
+++ b/src/client/Model/PaymentCategory.elm
@@ -2,15 +2,20 @@ module Model.PaymentCategory exposing
   ( PaymentCategories
   , paymentCategoriesDecoder
   , search
+  , groupPaymentsByCategory
   , isCategoryUnused
   , save
   )
 
 import Dict exposing (Dict)
 import Json.Decode as Decode exposing (Decoder)
+import List.Extra as List
+import Maybe.Extra as Maybe
 
 import Model.Category exposing (CategoryId, categoryIdDecoder)
+import Model.Payment exposing (Payments)
 import Utils.Json as Json
+import Utils.List as List
 import Utils.Search as Search
 
 type alias PaymentCategories = List PaymentCategory
@@ -26,18 +31,30 @@ paymentCategoriesDecoder =
     (Decode.field "name" Decode.string)
     (Decode.field "category" categoryIdDecoder)
 
+groupPaymentsByCategory : PaymentCategories -> Payments -> List (CategoryId, Payments)
+groupPaymentsByCategory paymentCategories payments =
+  payments
+    |> List.groupBy (\payment ->
+         search payment.name paymentCategories
+           |> Maybe.withDefault -1
+       )
+    |> List.filterMap (\(category, payments) ->
+         case category of
+           -1 -> Nothing
+           _ -> Just (category, payments)
+       )
+
 search : String -> PaymentCategories -> Maybe CategoryId
 search paymentName paymentCategories =
   paymentCategories
-    |> List.filter (\pc -> Search.format pc.name == Search.format paymentName)
-    |> List.head
+    |> List.find (\pc -> Search.format pc.name == Search.format paymentName)
     |> Maybe.map .category
 
 isCategoryUnused : CategoryId -> PaymentCategories -> Bool
 isCategoryUnused category paymentCategories =
   paymentCategories
-    |> List.filter ((==) category << .category)
-    |> List.isEmpty
+    |> List.find ((==) category << .category)
+    |> Maybe.isNothing
 
 save : String -> CategoryId -> PaymentCategories -> PaymentCategories
 save name category paymentCategories =