{-|
Copyright  :  (C) 2020, QBayLogic B.V.
License    :  BSD2 (see the file LICENSE)
Maintainer :  QBayLogic B.V. <devops@qbaylogic.com>
-}
{-# OPTIONS_GHC -fno-warn-unused-imports #-}
{-# LANGUAGE QuasiQuotes #-}

module Clash.Tests.Normalize.Transformations where

import Clash.Normalize.Transformations (inlineBndrsCleanup)
import Clash.Core.VarEnv
  (mkInScopeSet, mkVarSet, mkVarEnv, emptyVarEnv, extendInScopeSetList)
import Clash.Core.FreeVars (countFreeOccurances)
import Clash.Core.Term
import Clash.Unique (UniqSet, extendUniqSet, unitUniqSet)

import Test.Tasty
import Test.Tasty.HUnit

import Test.Clash.Rewrite (parseToTermQQ, parseToTerm)

import Debug.Trace
import Clash.Core.Pretty (showPpr)

t1337a :: Term
t1337a = Letrec keep1 result
 where
  (keep0:inlines)= map (\(v,e) -> (v,((v,e),countFreeOccurances e))) binds
  is = mkInScopeSet (mkVarSet (map fst binds))

  keep1 = inlineBndrsCleanup is (mkVarEnv inlines) emptyVarEnv [snd keep0]

  Letrec binds result =
    [parseToTermQQ|
      let
        -- Types don't mean anything for this example
        result_1, a_2, b_3, c_4 :: Int

        result_1 = a_2

        a_2 = b_3
        b_3 = c_4
        c_4 = a_2 b_3
      in
        result_1
    |]

t1337a_result :: Term
t1337a_result = [parseToTermQQ|
  let
    result_1, b_3 :: Int
    result_1 = b_3
    b_3 = b_3 b_3
  in
    result_1
|]

t1337b :: Term
t1337b = Letrec keep1 result
 where
  (keep0:inlines)= map (\(v,e) -> (v,((v,e),countFreeOccurances e))) binds
  is = mkInScopeSet (mkVarSet (map fst binds))

  keep1 = inlineBndrsCleanup is (mkVarEnv inlines) emptyVarEnv [snd keep0]

  Letrec binds result =
    [parseToTermQQ|
      let
        -- Types don't mean anything for this example
        result_1, a_2, b_3, c_4, d_5 :: Int

        result_1 = a_2

        a_2 = b_3
        b_3 = c_4
        c_4 = d_5
        d_5 = a_2 b_3 c_4
      in
        result_1
    |]

t1337b_result :: Term
t1337b_result = [parseToTermQQ|
  let
    result_1, c_4 :: Int
    result_1 = c_4
    c_4 = c_4 c_4 c_4
  in
    result_1
|]

t1337c :: Term
t1337c = Letrec keep1 result
 where
  (keep0:inlines)= map (\(v,e) -> (v,((v,e),countFreeOccurances e))) binds
  Var fv = parseToTerm "freevar_5 :: Int"
  is = mkInScopeSet (mkVarSet (fv : map fst binds))

  keep1 = inlineBndrsCleanup is (mkVarEnv inlines) emptyVarEnv [snd keep0]

  Letrec binds result =
    [parseToTermQQ|
      let
        result_1, a_2, b_3, c_4 :: Int

        result_1 = a_2

        a_2 = b_3
        b_3 = c_4
        c_4 = a_2 b_3 (freevar_5 :: Int)
      in
        result_1
    |]

t1337c_result :: Term
t1337c_result = [parseToTermQQ|
  let
    result_1, b_3 :: Int
    result_1 = b_3
    b_3 = b_3 b_3 (freevar_5 :: Int)
  in
    result_1
|]

tests :: TestTree
tests =
  testGroup
    "Clash.Tests.Core.Util.Interpolation"
    [ testCase "T1337a" $ t1337a_result @=? t1337a
    , testCase "T1337b" $ t1337b_result @=? t1337b
    , testCase "T1337c" $ t1337c_result @=? t1337c
    ]