Different mana types implemented with a Mana type class

Magic.hs

@@ -17,7 +17,8 @@ data Rarity = Land
 data Card = Card Rarity String Cost
     deriving (Show, Eq)
 
-instance ManaCost Card where
+instance Mana Card where
+    colors    (Card _ _ cost) = colors cost
     converted (Card _ _ cost) = converted cost
 
 data Deck = Deck [Card]
@@ -27,5 +28,8 @@ curve (Deck cards) = do
     let largest = maximum (map converted cards)
     map (\x -> (x, length (filter (\(Card rarity _ cost) -> rarity /= Land && converted cost == x) cards))) [0..largest]
 
-deck = Deck ((replicate 13 (Card Land "Swamp" (Cost []))) ++ (replicate 13 (Card Land "Plains" (Cost [])))
-    ++ replicate 4 (Card Mythic "Jace Beleren" (Cost [Mana 1 Colorless, Mana 2 Blue])))
+cards = concat $ [ replicate 13 (Card Land "Swamp" (Cost [] [] []))
+                 , replicate 13 (Card Land "Plains" (Cost [] [] []))
+                 , replicate  4 (Card Mythic "Jace Beleren" (Cost [Standard 1 Colorless, Standard 2 Blue] [] []))
+                 ]
+deck = Deck cards

Mana.hs

@@ -1,5 +1,8 @@
 module Mana where
 
+import Data.Char
+import Data.List
+
 data Color = Colorless
     | Black
     | White
@@ -8,35 +11,58 @@ data Color = Colorless
     | Green
     deriving (Show, Eq)
 
-data Mana = Mana { amount :: Int
-                 , color  :: Color
-                 } deriving (Show, Eq)
-
-data Cost = Cost [Mana]
-    deriving (Eq)
-
-instance Show Cost where
-    show c = pretty c
-
-class ManaCost a where
+class Mana a where
+    colors    :: a -> [Color]
     converted :: a -> Int
 
-instance ManaCost Cost where
-    converted (Cost []) = 0
-    converted (Cost cost) = (foldl (\t (Mana x _) -> t + x) 0) cost
+data Standard = Standard Int Color
+    deriving (Eq)
 
-pretty :: Cost -> String
-pretty c = do
-    let filtered c (Cost cost) = converted $ Cost $ filter (\x -> color x == c) cost
-    let colored = concat [ replicate (filtered Black c) 'B'
-                         , replicate (filtered White c) 'W'
-                         , replicate (filtered Red   c) 'R'
-                         , replicate (filtered Blue  c) 'U'
-                         , replicate (filtered Green c) 'G'
-                         ]
-    let colorless = filtered Colorless c
-    if length colored > 0 && colorless == 0 then
-        colored
-    else
-        (show colorless) ++ colored
+instance Mana Standard where
+    colors    (Standard _ x) = [x]
+    converted (Standard x _) = x
 
+instance Show Standard where
+    show      (Standard n c)
+        | c == Black = replicate n 'B'
+        | c == White = replicate n 'W'
+        | c == Red   = replicate n 'R'
+        | c == Blue  = replicate n 'U'
+        | c == Green = replicate n 'G'
+        | otherwise  = show n
+
+data Hybrid = Hybrid Standard Standard
+    deriving (Eq)
+
+instance Mana Hybrid where
+    colors    (Hybrid x y) = concat [colors x, colors y]
+    converted (Hybrid x y) = min (converted x) (converted y)
+
+instance Show Hybrid where
+    show (Hybrid x y) = map toLower $ "(" ++ (show x) ++ "/" ++ (show y) ++ ")"
+
+data Phyrexian = Phyrexian Standard
+    deriving (Eq)
+
+instance Mana Phyrexian where
+    colors    (Phyrexian x) = colors x
+    converted (Phyrexian x) = converted x
+
+instance Show Phyrexian where
+    show (Phyrexian x) = "(" ++ (map toLower $ show x) ++ "/p)"
+
+data Cost = Cost [Standard] [Hybrid] [Phyrexian]
+    deriving (Eq)
+
+instance Mana Cost where
+    colors    (Cost s h p) = nub $ concat $ [(concat $ map colors s), (concat $ map colors h), (concat $ map colors p)]
+    converted (Cost s h p) = (sum $ map converted s) + (sum $ map converted h) + (sum $ map converted p)
+
+instance Show Cost where
+    show (Cost s h p) = do
+        let colorless = filter (\x -> colors x == [Colorless]) s
+        let colored   = filter (\x -> colors x /= [Colorless]) s
+        concat [show $ sum $ map converted colorless
+               , concat $ map show p
+               , concat $ map show h
+               , concat $ map show colored]