module Waffle where

import List


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fresh n m = replicate n (replicate m False)

cols = length

fliprow = reverse . map not

showbd = map (map (\b -> if b then 'x' else 'o'))
prtbd  = putStrLn . unlines . showbd

data Move = L Int | R Int | T Int | B Int deriving Read

turn (T i) b = map fliprow (take i b) ++ drop i b
turn (B i) b = take j b ++ map fliprow (drop j b) 
               where j = cols b - i

turn (L i) b = transpose (turn (T i) (transpose b))
turn (R i) b = transpose (turn (B i) (transpose b))

play b = do prtbd b
            move <- getLine
            if null move then putStrLn "Bye!"
               else play (turn (read move) b)

waffle n m = play (fresh n m)




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-- extras

run moves n m = prtbd (foldl (flip turn) (fresh n m) moves)

-- middle = [H 2, H 3, V 2, H 2, H 3, V 2, H 2, H 3]