import Control.Monad (when)
import System.Cmd -- ideally this should use System.Process in the future, but for the sake of a first version this will do.
import System.Exit
import System.Console.GetOpt
import System.Environment
import Data.Maybe (maybe, isJust, fromMaybe)

import Test.Maybench

optList :: [OptDescr (String, String)]
optList =  [Option [] ["setup"] (ReqArg (\x -> ("setup",x)) "CMD") "Command to be run prior to benchmarking to prepare the environment.",
            Option [] ["setup1"] (ReqArg (\x -> ("setup1",x)) "CMD") "Command to be run prior to first benchmark to prepare the environment.",
            Option [] ["setup2"] (ReqArg (\x -> ("setup2",x)) "CMD") "Command to be run prior to second benchmark to prepare the environment.",
            Option [] ["cleanup"] (ReqArg (\x -> ("cleanup",x)) "CMD") "Command to be run post benchmarking to cleanup the environment.",
            Option [] ["cleanup1"] (ReqArg (\x -> ("cleanup1",x)) "CMD") "Command to be run post first benchmark to cleanup the environment.",
            Option [] ["cleanup2"] (ReqArg (\x -> ("cleanup2",x)) "CMD") "Command to be run post second benchmark to cleanup the environment.",
            Option ['n'] ["repetitions"] (ReqArg (\x -> ("repetitions",x)) "NUMBER") "Number of trials to run and average.",
            Option ['h'] ["help"] (NoArg ("help","help")) "Display usage information."]

optsDef :: [String] -> ([([Char], String)], [String], [String])
optsDef = getOpt Permute optList

help :: IO ()
help = do p <- getProgName
          putStrLn $ usageInfo (p ++ " cmd1 cmd2") optList
          exitWith ExitSuccess
          return ()

main :: IO ()
main = do args <- getArgs
          let opts = optsDef args
              lookupOpt opt = lookup opt . fst3 $ opts
              setup i   = fromMaybe "true" (lookupOpt ("setup" ++ show i))
              cleanup i = fromMaybe "true" (lookupOpt ("cleanup" ++ show i))
              iters = maybe 1 read $ lookupOpt "repetitions"
              test n c = averageTime c (setup n) (cleanup n) iters
          case opts of
           (_,[cmd1,cmd2],_) -> do
             when (isJust $ lookupOpt "help") help -- this exits
             system $ setup ""
             time1 <- test (1::Int) cmd1
             time2 <- test (2::Int) cmd2
             system $ cleanup ""
             maybe (return ()) putStrLn (compareTimes (cmd1, time1) (cmd2, time2))
           _ -> help
       where
        fst3 (x,_,_) = x