{-# LANGUAGE OverloadedStrings #-}

module Test.Nand2Tetris.VM
  (
    spec
  ) where

import Test.Hspec (Spec, describe, it, shouldBe)

import Nand2Tetris.VM (VMInstruction(VMMemAccess, VMArithmetic),
                       SegmentOffset(SegmentOffset),
                       AccessType(ACPush, ACPop),
                       SegmentId(SArgument, SLocal, SThis, SThat, SConstant, STemp, SPointer, SStatic),
                       SegmentOffset(SegmentOffset),
                       parseInstruction, ArithmeticCmd (ACAdd, ACNeg, ACSub, ACEq, ACGt, ACLt, ACAnd, ACOr, ACNot))
import Text.Megaparsec (runParser)

spec :: Spec
spec = do
  describe "parseInstruction" $ do
    it "Parses instruction: push argument 42" $
      doParse "push argument 42" `shouldBe` Right (VMMemAccess ACPush SArgument (SegmentOffset 42))

    it "Parses instruction: pop argument 42" $
      doParse "pop argument 42" `shouldBe` Right (VMMemAccess ACPop SArgument (SegmentOffset 42))

    it "Parses instruction: push local 42" $
      doParse "push local 42" `shouldBe` Right (VMMemAccess ACPush SLocal (SegmentOffset 42))

    it "Parses instruction: push this 42" $
      doParse "push this 42" `shouldBe` Right (VMMemAccess ACPush SThis (SegmentOffset 42))

    it "Parses instruction: push that 42" $
      doParse "push that 42" `shouldBe` Right (VMMemAccess ACPush SThat (SegmentOffset 42))

    it "Parses instruction: push constant 42" $
      doParse "push constant 42" `shouldBe` Right (VMMemAccess ACPush SConstant (SegmentOffset 42))

    it "Parses instruction: push static 42" $
      doParse "push static 42" `shouldBe` Right (VMMemAccess ACPush SStatic (SegmentOffset 42))

    it "Parses instruction: push pointer 42" $
      doParse "push pointer 42" `shouldBe` Right (VMMemAccess ACPush SPointer (SegmentOffset 42))

    it "Parses instruction: push temp 42" $
      doParse "push temp 42" `shouldBe` Right (VMMemAccess ACPush STemp (SegmentOffset 42))

    it "Parses instruction: push temp 11" $
      doParse "push temp 11" `shouldBe` Right (VMMemAccess ACPush STemp (SegmentOffset 11))

    it "Parses instruction: add" $
      doParse "add" `shouldBe` Right (VMArithmetic ACAdd)

    it "Parses instruction: sub" $
      doParse "sub" `shouldBe` Right (VMArithmetic ACSub)

    it "Parses instruction: neg" $
      doParse "neg" `shouldBe` Right (VMArithmetic ACNeg)

    it "Parses instruction: eq" $
      doParse "eq" `shouldBe` Right (VMArithmetic ACEq)

    it "Parses instruction: gt" $
      doParse "gt" `shouldBe` Right (VMArithmetic ACGt)

    it "Parses instruction: lt" $
      doParse "lt" `shouldBe` Right (VMArithmetic ACLt)

    it "Parses instruction: and" $
      doParse "and" `shouldBe` Right (VMArithmetic ACAnd)

    it "Parses instruction: or" $
      doParse "or" `shouldBe` Right (VMArithmetic ACOr)

    it "Parses instruction: not" $
      doParse "not" `shouldBe` Right (VMArithmetic ACNot)

  where
    doParse = runParser parseInstruction ""