Nav.hs

{-
 Copyright (C) 2017-2018 Johann Lee <me@qinka.pro>

 This file is part of Yu.

 Yu is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.

 Yu is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with Yu.  If not, see <http://www.gnu.org/licenses/>.
-}

{-|
Module:       Yu.Tool.Nav
Description:  codes about the nav bar
Copyright:    (C) 2017-2018 Johann Lee <me@qinka.pro>
License:      GPL3
Maintainer:   me@qinka.pro
Stability:    experimental
Portability:  unknown

codes about the nav bar
-}

{-# LANGUAGE RecordWildCards #-}

module Yu.Tool.Nav
  ( navHandler
  ) where

import           Data.List                 (nub)
import           System.IO
import           Yu.Import.Aeson
import qualified Yu.Import.ByteString.Lazy as BL
import           Yu.Tool.Opt               (Yu (navLabel, navOpt, navOrder, navUrl))
import qualified Yu.Tool.Opt               as O
import           Yu.Tool.Repo

-- | handler for nav
navHandler :: O.Yu -> IO ()
navHandler O.Nav{..} = do
  repo' <- findRepo yuRepoName
  case repo' of
    Nothing -> hPutStrLn stderr "Can not find the repo"
    Just repo -> let navListPath = repo ++ "/" ++ yuRepoName ++ "/navlist.json"
                 in  case navOpt of
      Nothing -> hPutStrLn stderr "Need options"
      Just "add" ->
        case (navLabel,navUrl,navOrder) of
          (Just label,Just url, Just order) -> do
            let nav = Nav order url label
            navs' <- decode <$> BL.readFile navListPath
            case navs' of
              Nothing   -> hPutStrLn stderr "Can not parse the nav list file"
              Just navs -> BL.writeFile navListPath $ encode $ nub (nav:navs)
          _ -> hPutStrLn stderr "need order, label, and url"
      Just "del" ->
        case navLabel of
          Nothing -> hPutStrLn stderr "Need nav's label"
          Just label -> do
            navs' <- decode <$> BL.readFile navListPath
            case navs' of
              Nothing   -> hPutStrLn stderr "Can not parse the nav list file"
              Just navs -> BL.writeFile navListPath $ encode $ filter (\x -> nLabel x /= label) navs
      _ -> hPutStrLn stderr "unknow option"