{-# LANGUAGE TemplateHaskell #-}

module TGenerate where

import           Test.Framework                 (testGroup)
import           Test.Framework.Providers.HUnit (testCase)
import           System.IO.Unsafe               (unsafePerformIO)
import           Test.HUnit

import           Generate hiding (melodyInC)
import           Generate.QuickCheck
import           Music
import           Data.Ratio
import qualified Data.Music.Lilypond as Ly

import           Control.Monad

ioFromGen = runGenerator (quickCheckState ())

genTests = testGroup "Generate"
  [ testCase "genNote yields a single note" $
      let res = ioFromGen (genNote)
      in (countNotes $ unsafePerformIO res) == 1 @? "unexpected note count",
    testCase "replicate generators yields correct number of results" $
      let res = ioFromGen (replicateM 10 genNote)
      in (countNotes (line $ unsafePerformIO res) == 10) @? "unexpected note count",
    testCase "pitchClass constraint" $
      let res = ioFromGen melodyInC
      in (all (inC . fst) $ unsafePerformIO res) @? "found notes not in the key of C"
  ]

instance Monoid Int where
  mappend = (+)
  mempty  = 0

countNotes :: Melody -> Int
countNotes = foldMap (const 1)

melodyInC :: MusicGenerator (GenState ()) Melody
melodyInC = do
  addConstraint pitchClass inC
  notes <- replicateM 20 genNote
  return $ line notes

inC :: PitchClass -> Bool
inC pc = elem pc [C, D, E, F, G, A, B]

inG :: PitchClass -> Bool
inG pc = elem pc [G, A, B, C, D, E, Fs, G]