-- |
-- Module      :  Main
-- Copyright   :  (c) OleksandrZhabenko 2019
-- License     :  MIT
-- Maintainer  :  olexandr543@yahoo.com
-- A program and a library that can be used as a musical instrument synthesizer or for Ukrainian speech synthesis 
-- especially for poets, translators and writers. 

module Main (
) where

import Data.Char (isSpace, isControl)
import Data.Maybe (isJust,fromJust)
import System.IO
import System.IO.Unsafe (unsafePerformIO)
import System.Environment (getArgs)
import System.Process (callProcess)
import System.Directory (removeFile,findExecutable)
import EndOfExe (showE)
import Paths_mmsyn6ukr
import Melodics.Ukrainian (appendS16LEFile, nSymbols, convertToProperUkrainian)

-- Inspired by: https://mail.haskell.org/pipermail/beginners/2011-October/008649.html

-- | The function creates a raw PCM sound file with bitrate 22050 Hz 1 mono channel 16-bit signed-integer encoding 
-- and tries to automatically convert it to the .wav file with the same parameters using the system binary SoX. 
-- If it is not installed properly, the program makes ending informational message for the user. 
-- Command line argument is described in more details in the documentation for the 'Melodics.Ukrainian.nSymbols' function. 
-- * Notification.
-- Please, notice that successful usage of the SoX installed in the system prior to the @mmsyn6ukr@ leads to approximately doubling 
-- the size of used space in the storage for the resulting files because it adds a header to the .raw file and writes down additionally 
-- the raw data to form a .wav file. Also notice that the size of the largest data file representing a symbol or their combination is 6792 bytes (with 44-byte 
-- header included). So, if you expect to create sounding for @n@ symbols of the Ukrainian text, provide at least @2 * (6792 - 44) * n + 44 = 13496 * n + 44@ (bytes) 
-- of the additional space in the storage (in reality it can occupy much less because other data files are less in size). Afterwards, the program deletes 
-- the .raw file (this will approximately halve the occupied space by the resulting file) and you can manually compress the .wav file 
-- (e. g. FLAC compression with the best ratio gives approxumately halving the size). Therefore, the resulting file 
-- for the @mmsyn6ukr@ executable run prior to such operations without command line arguments is expected to be less than about @10^7@ bytes that is about 100 MB 
-- (for 31416 symbols Ukrainian text).

main :: IO ()
main = do
         args <- getArgs
         putStrLn "Please, specify the name of the resulting sound file! Please, do NOT use '}' character and space or control characters!"
         nameOfSoundFile <- getLine
         let nameSF = filter (\x -> not (isSpace x) && not (isControl x) && x /= '}') nameOfSoundFile
         xs <- getContents
         let ys = take (nSymbols (let zs = take 1 args in if null zs then [] else head zs)) xs in
             withBinaryFile (nameSF ++ ".raw") AppendMode (appendS16LEFile (convertToProperUkrainian ys))
         let ts = showE "sox" in if isJust ts
                      then do
                             callProcess (fromJust . unsafePerformIO . findExecutable . fromJust $ ts) ["-r22050","-c1","-L","-esigned-integer","-b16", nameSF ++ ".raw", nameSF ++ ".wav"]
                             removeFile $ nameSF ++ ".raw"
                      else do
                         putStr "You have a resulting file in a raw PCM format with bitrate 22050 Hz and 1 channel (mono) in the .raw format. "
                         putStr "You can further process it by yourself manually, otherwise, please, install FFMpeg or LibAV executables in the directory mentioned in the variable PATH"
                         putStrLn " and then run: "
                         putStrLn "\"name_of_FFMpeg_or_LibAV_executable\" -f s16le -acodec pcm_s16le -ac 1 -ar 22050 -i \"name_Of_the_sound_file\" \"the_same_name_without_.raw_ending_and_with_.wav_ending\""
                         putStrLn ""
                         putStrLn "OR you can install SoX executable in the directory mentioned in the variable PATH and then run: "
                         putStrLn "\"Path_to_the_SoX_executable\" -b16 -r22050 -c1 -e signed-integer -L \"name_of_the_file_in_raw_format_with_new._prefix\" \"name_of_the_file_in_raw_format_with_new._prefix\" in the terminal."