import Test.QuickCheck
import Lib (isCongruent)

propCongruentDifference :: Int -> Int -> Int -> Property
propCongruentDifference a b m =
  m /= 0 ==> isCongruent a b m == ((a - b) `mod` m == 0)

propCongruentSymmetric :: Int -> Int -> Int -> Property
propCongruentSymmetric a b m =
  m /= 0 ==> isCongruent a b m == isCongruent b a m

propCongruentEqualNumbers :: Int -> Int -> Property
propCongruentEqualNumbers a m =
  m /= 0 ==> isCongruent a a m == True

main :: IO ()
main = do
  quickCheck propCongruentDifference
  quickCheck propCongruentSymmetric
  quickCheck propCongruentEqualNumbers