{-# LANGUAGE BangPatterns #-}

{-# LANGUAGE OverloadedStrings #-}

module Main (main) where

import Prelude ()

import Prelude.Compat

import Control.DeepSeq

import Control.Monad

import Data.Aeson

import Data.Attoparsec.ByteString (IResult(..), parseWith)

import Data.Char (isDigit)

import Data.Time.Clock

import System.Environment (getArgs)

import System.IO

import qualified Data.ByteString as B

main :: IO ()

main = do

  args0 <- getArgs

  let (cnt,args) = case args0 of

        (i:c:a) | all isDigit i && all isDigit c -> (c,a)

        (c:a) -> (c,a)

        [] -> error "Unexpected empty list"

  let count = read cnt :: Int

  forM_ args $ \arg -> withFile arg ReadMode $ \h -> do

    putStrLn $ arg ++ ":"

    let refill = B.hGet h 16384

    result0 <- parseWith refill json =<< refill

    r0 <- case result0 of

            Done _ r -> return r

            _        -> fail $ "failed to read " ++ show arg

    start <- getCurrentTime

    let loop !n r

            | n >= count = return ()

            | otherwise = {-# SCC "loop" #-}

          rnf (encode r) `seq` loop (n+1) r

    loop 0 r0

    delta <- flip diffUTCTime start `fmap` getCurrentTime

    let rate = fromIntegral count / realToFrac delta :: Double

    putStrLn $ "  " ++ cnt ++ " good, " ++ show delta

    putStrLn $ "  " ++ show (round rate :: Int) ++ " per second"