{- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
USAGE: hooty (-1|-4)? (-n <number to make>)?
The `hooty` program generates any number of UUIDs (one by default), using
either the version 1 (time and MAC) or version 4 (random) algorithm (version
1 is the default). On all platforms, `hooty` uses the native implementation.
-n, --number <number> Create <number> many UUIDs in one go.
-1, --sequential Create version 1 (time and MAC) UUIDs.
-4, --random Create version 4 (random) UUIDs.
-h, -?, --help Print this help and exit.
--version Print version and exit.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -}
{-# LANGUAGE TemplateHaskell
, PatternGuards
#-}
import qualified System.UUID.V1 as V1
import qualified System.UUID.V4 as V4
import Options
import Messages
import qualified Macros as Macros
import System.Environment
import System.Exit
import Control.Monad
import Control.Applicative
import Data.Maybe
import Data.Word
import qualified Data.Map as Map
main = do
m <- opts
let
lk = (`Map.lookup` m)
when (isJust $ lk "h") $ do
stdout << usage
exitWith ExitSuccess
when (isJust $ lk "version") $ do
stdout << version
exitWith ExitSuccess
when (all (isJust . lk) ["1","4"]) $ do
bail "Please specify either version 1 or version 4, not both."
let
n :: Word
n = fromMaybe 1 $ maybeRead =<< lk "n"
gen =
if isJust $ lk "4"
then V4.uuid
else V1.uuid
mapM_ (const $ print =<< gen) [1..n]
bail :: String -> IO a
bail s = do
stderr << s
stderr << usage
exitFailure
usage = $(Macros.usage)
version = "hooty-" ++ $(Macros.version)
opts = do
args <- getArgs
case runParser options () "command line arguments" args of
Right list -> return $ foldr ($) Map.empty list
Left e -> bail $ show e
options = do
res <- choice
[ eof >> return []
, many1 options'
]
eof
return res
options' = do
o <- choice opts
opt o
where
opt o@[c]
| c `elem` "h14" = return $ Map.insert o ""
| c == 'n' = choice
[ eof >> fail "Option requires an argument."
, try $ do
s <- initialChar '-'
fail $ "Option requiring argument followed by:\n " ++ s
, fmap (Map.insert o) anyString
]
| otherwise = prb $ "unimplemented option '" ++ o ++ "'"
opt "version" = return $ Map.insert "version" ""
opt o = prb $ "unimplemented option '" ++ o ++ "'"
prb s = fail $ "Please report a bug -- " ++ s ++ "."
opts = map try
[ option "h?" ["help"]
, option "1" ["sequential"]
, option "4" ["random"]
, option "n" ["number"]
, option "" ["version"]
] ++ [ fail "Invalid option." ]
maybeRead s
| [(a, _)] <- reads s = Just a
| otherwise = Nothing