{-|
Module      : Gargantext.Text.Parsers.RIS
Description : 
Copyright   : (c) CNRS, 2017-Present
License     : AGPL + CECILL v3
Maintainer  : team@gargantext.org
Stability   : experimental
Portability : POSIX


RIS is a standardized tag format developed by Research Information
Systems, Incorporated (the format name refers to the company) to enable
citation programs to exchange data.[More](https://en.wikipedia.org/wiki/RIS_(file_format))

-}

{-# LANGUAGE NoImplicitPrelude #-}
{-# LANGUAGE OverloadedStrings #-}

module Gargantext.Text.Parsers.RIS (risParser) where

import Control.Applicative
import Data.Attoparsec.ByteString (Parser, try, string, takeTill, take, manyTill, many1, endOfInput)
import Data.Attoparsec.ByteString.Char8 (anyChar, isEndOfLine)
import Data.ByteString (ByteString, concat)
import Data.ByteString.Char8 (pack)
import Data.Monoid ((<>))
import Gargantext.Prelude hiding (takeWhile, take, concat, readFile, lines, concat)
import qualified Data.List as DL

-------------------------------------------------------------

data Lines = OneLine | MultiLine

risParser :: Parser [[(ByteString, ByteString)]]
risParser = do
    n  <- notice "TY  -"
    ns <- many1 (notice "\nTY  -")
    pure $ [n] <> ns

notice :: Parser ByteString -> Parser [(ByteString, ByteString)]
notice s = start *> many field <* end
    where
      start :: Parser ByteString
      start = s *> takeTill isEndOfLine

      end :: Parser ByteString
      end =  "\nER  -" *> takeTill isEndOfLine

field :: Parser (ByteString, ByteString)
field = do
    name  <- "\n" *> take 2 <* "  - "
    txt   <- takeTill isEndOfLine
    txts  <- try lines
    let txts' = case DL.length txts > 0 of
            True  -> txts
            False -> []
    pure (translate name, concat ([txt] <> txts'))


lines :: Parser [ByteString]
lines = many line
    where
        line :: Parser ByteString
        line = "\n\n" *> takeTill isEndOfLine

translate :: ByteString -> ByteString
translate champs
            | champs == "AU" = "authors"
            | champs == "TI" = "title"
            | champs == "JF" = "source"
            | champs == "LA" = "language"
            | champs == "DI" = "doi"
            | champs == "UR" = "url"
            | champs == "DA" = "publication_date"
            | champs == "N2" = "abstract"
            | otherwise  = champs
-------------------------------------------------------------