4 files changed, 29 insertions, 15 deletions
diff --git a/src/client/Model/Income.elm b/src/client/Model/Income.elm
index 34578c6..aa5f05f 100644
--- a/src/client/Model/Income.elm
+++ b/src/client/Model/Income.elm
@@ -9,17 +9,16 @@ module Model.Income exposing
   , cumulativeIncomesSince
   )
 
+import Dict exposing (Dict)
 import Json.Decode as Decode exposing (Decoder)
-import Utils.Json as Json
-import Time exposing (Time, hour)
 import List exposing (..)
-import Dict exposing (Dict)
+import Maybe.Extra as Maybe
+import Time exposing (Time, hour)
+import Utils.Json as Json
 
 import Model.Date exposing (timeDecoder)
 import Model.User exposing (UserId, userIdDecoder)
 
-import Utils.Maybe as Maybe
-
 type alias Incomes = Dict IncomeId Income
 
 type alias IncomeId = Int
@@ -46,7 +45,7 @@ incomeDefinedForAll userIds incomes =
   let userIncomes = List.map (\userId -> List.filter ((==) userId << .userId) << Dict.values <| incomes) userIds
       firstIncomes = map (head << sortBy .time) userIncomes
   in  if all Maybe.isJust firstIncomes
-        then head << reverse << List.sort << map .time << Maybe.cat <| firstIncomes
+        then head << reverse << List.sort << map .time << Maybe.values <| firstIncomes
         else Nothing
 
 userCumulativeIncomeSince : Time -> Time -> Incomes -> UserId -> Int
diff --git a/src/client/Model/Payer.elm b/src/client/Model/Payer.elm
index 1663273..4d9190e 100644
--- a/src/client/Model/Payer.elm
+++ b/src/client/Model/Payer.elm
@@ -17,7 +17,6 @@ import Model.User exposing (Users, UserId, userIdDecoder)
 import Model.Income exposing (..)
 
 import Utils.Dict exposing (mapValues)
-import Utils.Maybe exposing (isJust)
 
 type alias Payers = Dict UserId Payer
 
diff --git a/src/client/Model/Payment.elm b/src/client/Model/Payment.elm
index 2412ab9..204f9f5 100644
--- a/src/client/Model/Payment.elm
+++ b/src/client/Model/Payment.elm
@@ -20,10 +20,11 @@ import Date.Extra.Core exposing (monthToInt, intToMonth)
 import Json.Decode as Decode exposing (Decoder)
 import Json.Decode.Extra as Decode
 import List
+import List.Extra as List
 
 import Form.Validate as Validate exposing (Validation)
-import Model.Frequency as Frequency exposing (Frequency(..))
 import Model.Date exposing (dateDecoder)
+import Model.Frequency as Frequency exposing (Frequency(..))
 import Model.User exposing (UserId, userIdDecoder)
 import Utils.List as List
 import Utils.Search as Search
@@ -63,8 +64,7 @@ paymentIdDecoder = Decode.int
 find : PaymentId -> Payments -> Maybe Payment
 find paymentId payments =
   payments
-    |> List.filter (\p -> p.id == paymentId)
-    |> List.head
+    |> List.find (\p -> p.id == paymentId)
 
 edit : Payment -> Payments -> Payments
 edit payment payments = payment :: delete payment.id payments
@@ -94,7 +94,6 @@ groupAndSortByMonth payments =
     |> List.groupBy (\payment -> (Date.year payment.date, monthToInt << Date.month <| payment.date))
     |> List.sortBy Tuple.first
     |> List.map (\((year, month), payments) -> ((intToMonth month, year), payments))
-    |> List.reverse
 
 search : String -> Frequency -> Payments -> Payments
 search name frequency payments =
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 =