module Main where

import System.Environment(getArgs)
import System.Exit(exitFailure)

import MiniWasm.Syntax
import MiniWasm.Validation
import MiniWasm.Execution
import MiniWasm.TestCases.Programs

printError :: String -> IO a
printError err = do
  putStrLn err
  exitFailure

validateAndExecute :: Module -> IO ()
validateAndExecute m =
  case validateModule m of
    Left e -> printError $ "Validation error: " ++ e
    Right () -> do
      let cfg = executeModule m
      case executeModule m of
        Config{instrs = []} -> print cfg.stack
        Config{instrs = [Trapping reason]} -> printError $ "Program trapped with " ++ show reason
        _ -> printError "Program didn't reach final state" -- This shouldn't happen unless you modify 'stepUntilFinal' or 'executeModule'

main :: IO ()
main = do
  args <- getArgs
  case args of
    [m] ->
      case lookup m testPrograms of
        Nothing -> printError "Unknown module name"
        Just (m, _) -> validateAndExecute m
    _ -> do
      printError $
        "Usage:\n\
        \  miniwasm <module-name>   # Validate and execute the specified MiniWasm module\n\
        \\n\
        \Available modules:\n"
        ++ unlines (fmap ("  " ++) $ fmap fst testPrograms)