-- |
-- Module      :  EspeakNG_IPA
-- Copyright   :  (c) OleksandrZhabenko 2021
-- License     :  MIT
-- Stability   :  Experimental
-- Maintainer  :  olexandr543@yahoo.com
--
-- Is intended to use internally \"espeak-ng\" or \"espeak\" executable to produce the IPA phonemes output
-- of the given 'String'.
-- The prerequisite is installed espeak-ng or espeak executable in the path that is in the PATH
-- environment variable. 

module EspeakNG_IPA where

import System.Process (readProcessWithExitCode)
import EndOfExe (showE)
import System.Exit (ExitCode(..))
import Data.Maybe (fromJust)

{-| Given a language 'String' supported by the espeak-ng or espeak (which one is installed properly) and the
needed text returns the IPA representation. Is just some wrapper around the espeak functionality. -}
espeakNG_IPA :: String -> String -> IO String
espeakNG_IPA lang xs =
 case showE "espeak-ng" of
   Just path -> readProcessWithExitCode path ("-xq":"--ipa":"-l":[lang]) xs >>=
     \(hcode,hout,herr) -> case hcode of
        ExitSuccess -> return (unwords . lines $ hout)
        _ -> error ("EspeakNG_IPA.espeakNG_IPA: " ++ show herr)
   _ -> case showE "espeak" of
          Just path2 -> readProcessWithExitCode path2 ("-xq":"--ipa":"-l":[lang]) xs >>=
            \(hcode,hout,herr) -> case hcode of
               ExitSuccess -> return (unwords . lines $ hout)
               _ -> error ("EspeakNG_IPA.espeakNG_IPA: " ++ show herr)
          _ -> error ("EspeakNG_IPA.espeakNG_IPA: No espeak or espeak-ng executable is installed in the PATH directories. ")

{-| Given a language 'String' supported by the espeak-ng or espeak (which one is installed properly) and the
needed text prints the IPA representation. Is just some wrapper around the espeak functionality. -}  
espeakNG_IPA_ :: String -> String -> IO ()
espeakNG_IPA_ lang xs =
   case showE "espeak-ng" of
   Just path -> readProcessWithExitCode path ("-xq":"--ipa":"-l":[lang]) xs >>=
     \(hcode,hout,herr) -> case hcode of
        ExitSuccess -> putStrLn (unwords . lines $ hout)
        _ -> error ("EspeakNG_IPA.espeakNG_IPA_: " ++ show herr)
   _ -> case showE "espeak" of
          Just path2 -> readProcessWithExitCode path2 ("-xq":"--ipa":"-l":[lang]) xs >>=
            \(hcode,hout,herr) -> case hcode of
               ExitSuccess -> putStrLn (unwords . lines $ hout)
               _ -> error ("EspeakNG_IPA.espeakNG_IPA_: " ++ show herr)
          _ -> error ("EspeakNG_IPA.espeakNG_IPA_: No espeak or espeak-ng executable is installed in the PATH directories. ")