Showing exceeding payers

3 files changed, 39 insertions, 1 deletions

diff --git a/src/server/Model/Database.hs b/src/server/Model/Database.hs
index 8715ca1..a6ce4f4 100644
--- a/src/server/Model/Database.hs
+++ b/src/server/Model/Database.hs
@@ -26,7 +26,7 @@ User
   creation UTCTime
   email Text
   name Text
-  EmailKey email
+  UniqEmail email
   UniqName name
   deriving Show
 Payment
diff --git a/src/server/Model/Json/TotalPayment.hs b/src/server/Model/Json/TotalPayment.hs
new file mode 100644
index 0000000..e386c79
--- /dev/null
+++ b/src/server/Model/Json/TotalPayment.hs
@@ -0,0 +1,18 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Model.Json.TotalPayment
+  ( TotalPayment(..)
+  ) where
+
+import GHC.Generics
+
+import Data.Text (Text)
+import Data.Aeson
+
+data TotalPayment = TotalPayment
+  { userName :: Text
+  , totalPayment :: Int
+  } deriving (Show, Generic)
+
+instance FromJSON TotalPayment
+instance ToJSON TotalPayment
diff --git a/src/server/Model/Payment.hs b/src/server/Model/Payment.hs
index 51f09b9..300f6b8 100644
--- a/src/server/Model/Payment.hs
+++ b/src/server/Model/Payment.hs
@@ -3,11 +3,13 @@ module Model.Payment
   , createPayment
   , paymentKeyToText
   , deleteOwnPayment
+  , getTotalPayments
   ) where
 
 import Data.Text (Text)
 import qualified Data.Text as T
 import Data.Time.Clock (getCurrentTime)
+import Data.Maybe (catMaybes)
 
 import Control.Monad.IO.Class (liftIO)
 
@@ -18,6 +20,7 @@ import qualified Database.Esqueleto as E
 
 import Model.Database
 import qualified Model.Json.Payment as P
+import qualified Model.Json.TotalPayment as TP
 
 getPayments :: Persist [P.Payment]
 getPayments = do
@@ -62,3 +65,20 @@ deleteOwnPayment user paymentId = do
           return False
     Nothing ->
       return False
+
+getTotalPayments :: Persist [TP.TotalPayment]
+getTotalPayments = do
+  values <- select $
+            from $ \(payment `InnerJoin` user) -> do
+              on (payment ^. PaymentUserId E.==. user ^. UserId)
+              where_ (isNothing (payment ^. PaymentDeletedAt))
+              groupBy (payment ^. PaymentUserId)
+              return (user ^. UserName, sum_ (payment ^. PaymentCost))
+  return $ catMaybes . map (getTotalPayment . unValueTuple) $ values
+
+getTotalPayment :: (Text, Maybe Int) -> Maybe TP.TotalPayment
+getTotalPayment (userName, Just cost) = Just (TP.TotalPayment userName cost)
+getTotalPayment (_, Nothing) = Nothing
+
+unValueTuple :: (Value a, Value b) -> (a, b)
+unValueTuple (Value a, Value b) = (a, b)