{- |

Module : $Header$

Description : simple command line dialogs

Copyright : (c) C. Maeder, Uni Bremen 2002-2005

License : GPLv2 or higher, see LICENSE.txt

Maintainer : Christian.Maeder@dfki.de

Stability : provisional

Portability : portable

gui utilities that work via the console instead of using HTk

The interface should remain compatible with GUI.HTkUtils

so that GUI.Utils can reexport functions of both modules

based on the presence of UNI_PACKAGE.

-}

module GUI.ConsoleUtils where

import Data.Char

import Data.List

import Control.Monad ( unless )

-- | present a list of choices and return the selection

listBox :: String -> [String] -> IO (Maybe Int)

listBox prompt choices = do

putStrLn prompt

mapM_ putStrLn $ zipWith (\ n -> (shows n ": " ++)) [0 :: Int ..] choices

putStrLn "Please enter a number on the next line"

s <- getLine

if all isDigit s then

let n = foldl ( \ r a -> r * 10 + digitToInt a) 0 s in

if n >= length choices then

putStrLn "number to large, try again"

>> listBox prompt choices

else putStrLn ("you have chosen entry \"" ++ choices !! n)

>> return (Just n)

else putStrLn ("illegal input \"" ++ s ++ "\" try again")

>> listBox prompt choices

-- | show text and ask to save it

createTextSaveDisplay :: String -- ^ title of the window

-> String -- ^ default filename for saving the text

-> String -- ^ text to be displayed

-> IO ()

createTextSaveDisplay t f txt = do

putStrLn t

putStrLn $ replicate (length t) '='

putStrLn ""

putStrLn txt

putStrLn ""

askFileNameAndSave f txt

-- | ask for a file name

askFileNameAndSave :: String -- ^ default filename for saving the text

-> String -- ^ text to be saved

-> IO ()

askFileNameAndSave f txt = do

putStrLn $ "save text in file \"" ++ f ++ "\"? (y/n)"

s <- getLine

if "y" `isPrefixOf` map toLower s then writeFile f txt

else do

putStrLn "enter new file name (or abort with return):"

n <- getLine

unless (null n) $ askFileNameAndSave n txt