import Control.Applicative ((<|>))
import Control.Monad (forM_)
import Data.Char (isDigit, isLetter)
import System.Environment (getArgs)
import qualified Data.Attoparsec.Char8 as AB
import qualified Data.ByteString.Char8 as B
import qualified Data.Attoparsec.Text as A
import qualified Data.Text as T
import qualified Data.Text.IO as T
import qualified Text.Parsec as P
import qualified Text.Parsec.ByteString as P


attoparsec_bytestring args = do
  forM_ args $ \arg -> do
    input <- B.readFile arg
    case AB.parse p input `AB.feed` B.empty of
      AB.Done _ xs -> print (length xs)
      what        -> print what
 where
  slow = AB.many (AB.many1 AB.letter_ascii <|> AB.many1 AB.digit)
  fast = AB.many (AB.takeWhile1 isLetter <|> AB.takeWhile1 isDigit)
  isDigit c  = c >= '0' && c <= '9'
  isLetter c = (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')
  p = fast

attoparsec_text args = do
  forM_ args $ \arg -> do
    input <- T.readFile arg
    case A.parse p input `A.feed` T.empty of
      A.Done _ xs -> print (length xs)
      what        -> print what
 where
  p = A.many (A.takeWhile1 isLetter <|> A.takeWhile1 isDigit)

parsec args =
  forM_ args $ \arg -> do
    input <- readFile arg
    case P.parse (P.many (P.many1 P.letter P.<|> P.many1 P.digit)) "" input of
      Left err -> print err
      Right xs -> print (length xs)

main = do
  args <- getArgs
  case args of
    ("attoparsec_bytestring":xs) -> attoparsec_bytestring xs
    ("attoparsec_text":xs) -> attoparsec_text xs
    ("parsec":xs) -> parsec xs
    [] -> putStrLn "Usage: ... [parsec|attoparsec_text|attoparsec_bytestring] inputs"