module Main where

import Data.Bits
import Test.QuickCheck hiding ((.&.))
import Data.GraphViz
import Data.Graph.Inductive.Example (clr479, dag4)
import Data.Text.Lazy
import Data.GraphViz.Printing
import Data.Graph.Inductive.Graph
import Data.Graph.Inductive.PatriciaTree

type Input = Bool

data Gate = And
          | Or
          | Xor
          | Nand
          | Nor
          deriving (Show)

data Circuit a = In a
               | Node Gate (Circuit a) (Circuit a)
               deriving (Show)

instance Arbitrary Gate where
  arbitrary = elements [And, Or, Xor, Nand, Nor]

instance (Arbitrary a) => Arbitrary (Circuit a) where
  arbitrary = do
    x <- arbitrary
    frequency [(1, return (In x)), (1, arbNode)]
      where
        arbNode = Node <$> arbitrary <*> arbitrary <*> arbitrary

eval :: (Bits a) => Circuit a -> a
eval (In val) = val
eval (Node And c1 c2) = eval c1 .&. eval c2
eval (Node Or c1 c2) = eval c1 .|. eval c2
eval (Node Xor c1 c2) = eval c1 `xor` eval c2
eval (Node Nand c1 c2) = complement $ eval c1 .&. eval c2
eval (Node Nor c1 c2) = complement $ eval c1 .|. eval c2

visualize :: (Show a) => Circuit a -> Gr String String
visualize circ =
  uncurry mkGraph $ graph Nothing 0 ([], []) circ
  where
    graph parent nl (l, e) circ =
      case (parent, circ) of
        (Nothing, (In val)) ->
          ((nl, "In: " ++ show val) : l, e)
        (Just par, (In val)) ->
          ((nl, "In: " ++ show val) : l, (par, nl, "") : e) 
        _ ->
          ([], [])

main :: IO ()
--main = sample (arbitrary :: Gen (Circuit Input))
main = preview $ visualize (In True)