module UnitTests.Distribution.Client.IndexUtils.Timestamp (tests) where

import Data.Time
import Data.Time.Clock.POSIX
import Distribution.Parsec (simpleParsec)
import Distribution.Pretty (prettyShow)

import Distribution.Client.IndexUtils.Timestamp

import Test.Tasty
import Test.Tasty.QuickCheck

tests :: [TestTree]
tests =
  [ testProperty "Timestamp1" prop_timestamp1
  , testProperty "Timestamp2" prop_timestamp2
  , testProperty "Timestamp3" prop_timestamp3
  , testProperty "Timestamp4" prop_timestamp4
  , testProperty "Timestamp5" prop_timestamp5
  ]

-- test unixtime format parsing
prop_timestamp1 :: NonNegative Int -> Bool
prop_timestamp1 (NonNegative t0) = Just t == simpleParsec ('@' : show t0)
  where
    t = epochTimeToTimestamp $ toEnum t0 :: Timestamp

-- test prettyShow/simpleParse roundtrip
prop_timestamp2 :: Int -> Bool
prop_timestamp2 t0 = simpleParsec (prettyShow t) == Just t
  where
    t = epochTimeToTimestamp $ toEnum t0 :: Timestamp

-- test prettyShow against reference impl
prop_timestamp3 :: Int -> Bool
prop_timestamp3 t0 = refDisp t == prettyShow t
  where
    t = epochTimeToTimestamp $ toEnum t0 :: Timestamp

    refDisp =
      maybe undefined (formatTime undefined "%FT%TZ")
        . timestampToUTCTime

-- test utcTimeToTimestamp/timestampToUTCTime roundtrip
prop_timestamp4 :: Int -> Bool
prop_timestamp4 t0 =
  (utcTimeToTimestamp <$> timestampToUTCTime t) == Just t
  where
    t = epochTimeToTimestamp $ toEnum t0 :: Timestamp

prop_timestamp5 :: Int -> Bool
prop_timestamp5 t0 = timestampToUTCTime t == Just ut
  where
    t = epochTimeToTimestamp $ toEnum t0 :: Timestamp
    ut = posixSecondsToUTCTime (fromIntegral t0)