close to solution for part 1

day02/lib/Day02.hs

@@ -1,2 +1,29 @@
 module Day02 where
 
+import Data.Maybe (fromMaybe)
+import Text.Read (readMaybe)
+
+data Move = Horizontal Int | Depth Int deriving Show
+
+readDataLines:: (String -> Maybe a) -> String -> Either String [a]
+readDataLines f s = case mapM f (lines s) of
+                      Just xs -> Right xs
+                      Nothing -> Left "Error parsing string"
+
+day02Part1 :: String -> String
+day02Part1 _ = "Day02 Part1"
+
+
+day02Part2 :: String -> String
+day02Part2 _ = "Day02 Part2"
+
+readDirection ::String -> Maybe (Int -> Move)
+readDirection "forward" = Just Horizontal
+readDirection "down" = Just Depth
+readDirection "up" = Just (Depth . negate)
+readDirection _ = Nothing
+
+readMove :: String -> Maybe Move
+readMove s = case words s of
+               [dirStr, distStr] -> readDirection dirStr <*> readMaybe distStr
+               _ -> Nothing