Calendar.hs

{-# LANGUAGE MultiParamTypeClasses  #-}
{-# LANGUAGE FunctionalDependencies #-}
module Grocery.Database.Calendar where

import Grocery.DatabaseSchema
import Grocery.Types.Meal
import Database.Persist
import Database.Persist.Sqlite
import qualified Database.Esqueleto      as E
import           Database.Esqueleto      ((^.))
import Data.Time
import Control.Monad.Trans -- for MonadIO

getMeals :: (MonadIO m) => DbUserId -> SqlPersistT m [Meal]
getMeals user = do
  r <- E.select $
        E.from $ \(m `E.InnerJoin` u) -> do
          E.on     (m ^. DbMealUserId E.==. u ^. DbUserId)
          E.where_ (m ^. DbMealUserId E.==. E.val user )
          return m
  return $ map (deserializeDb . entityVal) r

class DeserializeDb a r | a -> r where
  deserializeDb :: a -> r

instance DeserializeDb DbMeal Meal where
  deserializeDb db = let d = dbMealDay db
                         n = dbMealName db
                     in  Meal Nothing (utctDay d) n []