lib/Card.hs
2018-02-26 09:03:43 +01:00

115 lines
2.5 KiB
Haskell

module Card where
import Data.Word (Word64)
import Data.Bits (
clearBit
, popCount
, setBit
, shift
, testBit
, xor
, Bits
, (.&.)
, (.|.)
, countTrailingZeros
)
import System.Random (randomRIO)
data Flower =
Pine
| Plum
| Cherry
| Wisteria
| Iris
| Peony
| BushClover
| SusukiGrass
| Chrysanthemum
| Maple
| Willow
| Paulownia
deriving (Eq, Ord, Enum, Show)
data Card =
Pine0 | Pine1 | PinePoetry | Crane
| Plum0 | Plum1 | PlumPoetry | BushWarbler
| Cherry0 | Cherry1 | CherryPoetry | CampCurtain
| Wisteria0 | Wisteria1 | WisteriaRed | Cuckoo
| Iris0 | Iris1 | IrisRed | EightPlankBridge
| Peony0 | Peony1 | PeonyBlue | Butterflies
| BushClover0 | BushClover1 | BushCloverRed | Boar
| SusukiGrass0 | SusukiGrass1 | Geese | FullMoon
| Chrysanthemum0 | Chrysanthemum1 | ChrysanthemumBlue | SakeCup
| Maple0 | Maple1 | MapleBlue | Deer
| Lightning | WillowRed | Swallow | RainMan
| Paulownia0 | Paulownia1 | Sand | Phoenix
deriving (Eq, Ord, Enum, Show)
flower :: Card -> Flower
flower = toEnum . (`div` 4) . fromEnum
type Pack = Word64
empty :: Pack
empty = 0
packOfCards :: [Card] -> Pack
packOfCards = foldl setBit 0 . map fromEnum
smallest :: Pack -> Card
smallest = toEnum . countTrailingZeros
cardsOfPack :: Pack -> [Card]
cardsOfPack 0 = []
cardsOfPack pack =
let n = countTrailingZeros pack in
toEnum n : cardsOfPack (clearBit pack n)
port :: (Bits a, Enum e) => (a -> Int -> b) -> a -> e -> b
port f bits = f bits . fromEnum
contains :: Pack -> Card -> Bool
contains = port testBit
size :: Pack -> Int
size = popCount
add :: Pack -> Card -> Pack
add = port setBit
remove :: Pack -> Card -> Pack
remove = port clearBit
union :: Pack -> Pack -> Pack
union = (.|.)
intersection :: Pack -> Pack -> Pack
intersection = (.&.)
difference :: Pack -> Pack -> Pack
difference a b = a `xor` (a .&. b)
sameMonth :: Card -> Pack
sameMonth card = 0xf `shift` (fromEnum card .&. 0xfc)
cards :: [Card]
cards = [Pine0 .. Phoenix]
shuffle :: [a] -> IO [a]
shuffle l =
aux (length l) l
where
aux n [] = return []
aux n (h:t) = do
cut <- randomRIO (0, n-1)
shuffled <- shuffle t
let (top, bottom) = splitAt cut shuffled
return $ top ++ h : bottom
pair :: Card -> Pack -> Maybe (Pack, Pack)
pair card pack =
let sameMonthCards = sameMonth card `intersection` pack in
case size sameMonthCards of
0 -> Just (add pack card, empty)
1 -> Just (difference pack sameMonthCards, add sameMonthCards card)
_ -> Nothing