twin/app/Main.hs

module Main where

import System.Directory
import Options.Applicative
import Data.List

data CgiState = CgiSuccess
instance Show CgiState where
    show CgiSuccess = "20 text/gemini; lang=en; charset=utf-8\r"

data Args = Args
    { title :: String
    , directory :: FilePath
    , fileHead :: FilePath
    , verbose :: Bool
    , names :: Bool
    , cgi :: Bool
    }

args :: Parser Args
args = Args
    <$> strOption ( long "title" <> short 't' <> value "Title Left Blank" <> help "Document title" )
    <*> strOption ( long "directory" <> short 'd' <> value "./" <> help "Directory to parse" )
    <*> strOption ( long "header" <> short 'H' <> value "" <> help "Header text" )
    <*> switch ( long "verbose" <> short 'v' <> help "Verbose mode")
    <*> switch ( long "names" <> short 'n' <> help "Generate link names based on first of each document" )
    <*> switch ( long "cgi" <> help "Output gemini file header")

main :: IO ()
main = parseArgs =<< execParser opts
  where
    opts = info ( args <**> helper)
        ( fullDesc
       <> progDesc "Generate  gemini page index"
       <> header "Generate a gemini page index")

parseArgs :: Args -> IO()
parseArgs (Args t dir h v r c) = do
    if c
    then do print CgiSuccess
            putStrLn $ "# " ++ t
    else putStrLn $ "# " ++ t

    if not (null h)
    then putStr $ "\n" ++ h ++ "\n\n"
    else putStr "\n"

    mapM_ (mkIndex r dir) . filter (isSuffixOf ".gmi") =<< getDirectoryContents dir

mkIndex :: Bool -> FilePath -> FilePath -> IO ()

mkIndex False d l = putStrLn $ "=> " ++ path
    where path = d++"/"++l

mkIndex True d l = do
    line <- trim . words . head . lines <$> readFile path
    putStrLn $ "=> " ++ path ++ " " ++ line
    where path = d++"/"++l
          trim s
            | length s >= 8 = (++ "...") . unwords . take 8 . cleanString $ s
            | otherwise = unwords . cleanString $ s
            -- remove all '#' signs and any potential resulting empty lists
            where cleanString = filter(/="") . map (dropWhile (=='#'))