module Tests.FromPTerm

import Quox.Parser.FromParser
import Quox.Parser
import TypingImpls
import Tests.Parser as TParser
import Quox.EffExtra
import TAP
import AstExtra
import PrettyExtra

import System.File
import Derive.Prelude
%language ElabReflection

%hide TParser.Failure
%hide TParser.ExpectedFail

public export
data Failure =
    ParseError Parser.Error
  | FromParser FromParser.Error
  | WrongResult String
  | ExpectedFail String

%runElab derive "FileError" [Show]

export
ToInfo Failure where
  toInfo (ParseError err) = toInfo err
  toInfo (FromParser err) =
    [("type", "FromParserError"),
     ("got", prettyStr $ prettyError True err)]
  toInfo (WrongResult got) =
    [("type", "WrongResult"), ("got", got)]
  toInfo (ExpectedFail got) =
    [("type", "ExpectedFail"), ("got", got)]


parameters {c : Bool} {auto _ : Show b}
           (grm : FileName -> Grammar c a)
           (fromP : a -> Either FromParser.Error b)
           (inp : String)
  parameters {default (ltrim inp) label : String}
    parsesWith : (b -> Bool) -> Test
    parsesWith p = test label $ do
      pres <- mapFst ParseError $ lexParseWith (grm "‹test›") inp
      res  <- mapFst FromParser $ fromP pres
      unless (p res) $ Left $ WrongResult $ show res

    parses : Test
    parses = parsesWith $ const True

    %macro
    parseMatch : TTImp -> Elab Test
    parseMatch pat =
      parsesWith <$> check `(\case ~(pat) => True; _ => False)

    parsesAs : Eq b => b -> Test
    parsesAs exp = parsesWith (== exp)

  parameters {default "\{ltrim inp}  # fails" label : String}
    parseFails : Test
    parseFails = test label $ do
      pres <- mapFst ParseError $ lexParseWith (grm "‹test›") inp
      either (const $ Right ()) (Left . ExpectedFail . show) $ fromP pres


runFromParser : {default empty defs : Definitions} ->
                Eff FromParserPure a -> Either FromParser.Error a
runFromParser = map fst . fst . fromParserPure 0 defs

export
tests : Test
tests = "PTerm → Term" :- [
  "dimensions" :-
  let fromPDim = runFromParser . fromPDimWith [< "𝑖", "𝑗"]
  in [
    note "dim ctx: [𝑖, 𝑗]",
    parseMatch dim fromPDim "𝑖" `(B (VS VZ) _),
    parseMatch dim fromPDim "𝑗" `(B VZ _),
    parseFails dim fromPDim "𝑘",
    parseMatch dim fromPDim "0" `(K Zero _),
    parseMatch dim fromPDim "1" `(K One _)
  ],

  "terms" :-
  let defs = fromList [("f", mkDef gany (Nat noLoc) (Zero noLoc) noLoc)]
        -- doesn't have to be well typed yet, just well scoped
      fromPTerm = runFromParser {defs} .
                  fromPTermWith [< "𝑖", "𝑗"] [< "A", "x", "y", "z"]
  in [
    note "dim ctx: [𝑖, 𝑗]; term ctx: [A, x, y, z]",
    parseMatch term fromPTerm "x" `(E $ B (VS $ VS VZ) _),
    parseFails term fromPTerm "𝑖",
    parseMatch term fromPTerm "f" `(E $ F "f" _),
    parseMatch term fromPTerm "λ w ⇒ w"
      `(Lam (S _ $ Y $ E $ B VZ _) _),
    parseMatch term fromPTerm "λ w ⇒ x"
      `(Lam (S _ $ N $ E $ B (VS $ VS VZ) _) _),
    parseMatch term fromPTerm "λ x ⇒ x"
      `(Lam (S _ $ Y $ E $ B VZ _) _),
    parseMatch term fromPTerm "λ a b ⇒ f a b"
      `(Lam (S _ $ Y $
          Lam (S _ $ Y $
            E $ App (App (F "f" _) (E $ B (VS VZ) _) _) (E $ B VZ _) _) _) _),
    parseMatch term fromPTerm "f @𝑖" $
      `(E $ DApp (F "f" _) (B (VS VZ) _) _)
  ],

  todo "everything else"
]