subtree(users/wpcarro): docking briefcase at '24f5a642'

git-subtree-dir: users/wpcarro
git-subtree-mainline: 464bbcb15c
git-subtree-split: 24f5a642af
Change-Id: I6105b3762b79126b3488359c95978cadb3efa789

users/wpcarro/assessments/tt/src/Trips.hs

@@ -0,0 +1,42 @@
+{-# LANGUAGE OverloadedStrings #-}
+--------------------------------------------------------------------------------
+module Trips where
+--------------------------------------------------------------------------------
+import Database.SQLite.Simple
+import Utils
+
+import qualified Types as T
+--------------------------------------------------------------------------------
+
+-- | Create a new `trip` in `dbFile`.
+create :: FilePath -> T.Trip -> IO ()
+create dbFile trip = withConnection dbFile $ \conn ->
+  execute conn "INSERT INTO Trips (username,destination,startDate,endDate,comment) VALUES (?,?,?,?,?)"
+    (trip |> T.tripFields)
+
+-- | Attempt to get the trip record from `dbFile` under `tripKey`.
+get :: FilePath -> T.TripPK -> IO (Maybe T.Trip)
+get dbFile tripKey = withConnection dbFile $ \conn -> do
+  res <- query conn "SELECT username,destination,startDate,endDate,comment FROM Trips WHERE username = ? AND destination = ? AND startDate = ? LIMIT 1"
+    (T.tripPKFields tripKey)
+  case res of
+    [x] -> pure (Just x)
+    _ -> pure Nothing
+
+-- | Delete a trip from `dbFile` using its `tripKey` Primary Key.
+delete :: FilePath -> T.TripPK -> IO ()
+delete dbFile tripKey =
+  withConnection dbFile $ \conn -> do
+    execute conn "DELETE FROM Trips WHERE username = ? AND destination = ? and startDate = ?"
+      (T.tripPKFields tripKey)
+
+-- | Return a list of all of the trips in `dbFile`.
+listAll :: FilePath -> IO [T.Trip]
+listAll dbFile = withConnection dbFile $ \conn ->
+  query_ conn "SELECT username,destination,startDate,endDate,comment FROM Trips ORDER BY date(startDate) ASC"
+
+-- | Return a list of all of the trips in `dbFile`.
+list :: FilePath -> T.Username -> IO [T.Trip]
+list dbFile username = withConnection dbFile $ \conn ->
+  query conn "SELECT username,destination,startDate,endDate,comment FROM Trips WHERE username = ? ORDER BY date(startDate) ASC"
+    (Only username)