Start work on cards

Cards.hs

@@ -0,0 +1,59 @@
+module Cards
+  ( Element
+  , Card
+  , Comment
+  , isCard
+  , sides
+  , resetLevel
+  , nextLevel
+  , showElement
+  , showElements
+  , parseElement
+  , parseElements
+  ) where
+
+data Element = ECard Card | EComment Comment
+  deriving (Show)
+
+data Comment = Comment String
+  deriving (Show)
+
+type LastChecked = Integer
+type Delay = Integer
+data Card = Card Tier LastChecked Delay [String]
+  deriving (Show)
+
+data Tier = Zero | One | Two | Three | Four | Five | Six | Seven | Eight | Nine | Ten
+  deriving (Show, Eq, Ord, Enum, Bounded)
+
+{-
+ - Basic utility functions
+ -}
+
+isCard :: Element -> Bool
+isCard (ECard _) = True
+isCard _         = False
+
+sides :: Card -> [String]
+sides (Card _ _ _ s) = s
+
+resetTier :: Card -> Card
+resetTier (Card t l d s) = Card minBound l d s
+
+nextTier :: Card -> Card
+nextTier c@(Card t l d s)
+  | t == maxBound = c
+  | otherwise     = Card (succ t) l d s
+
+showElements :: [Element] -> String
+showElements = intercalate "\n\n" . map showElement
+
+showElement :: Element -> String
+showElement = undefined
+
+{-
+ - Parsing
+ -}
+
+parseElements = undefined
+parseElement = undefined