{- WEI HU: yi-0.4 seems to have changed API a lot. The examples must be adapted accordingly.
   You have to dive into the source code to figure out the changes.

   Helpful resources include:
   Different modes under Yi/Keymap, an incompatible tutorial at http://www.nobugs.org/developer/yi/,
   the incomplete documentation at http://code.haskell.org/yi/doc/, and a paper at
   http://www.cse.unsw.edu.au/~dons/papers/yi.pdf
 -}

import Yi
import Yi.Keymap.Emacs (keymap, makeKeymap)
import qualified Yi.Mode.Shim as Shim
import Yi.UI.Common (UIConfig(..))
import Yi.Modes
import Data.List (isSuffixOf)
import Yi.Prelude
import Yi.Mode.Haskell
import qualified Data.Map as M
import Data.Dynamic
import qualified Yi.UI.Vty

bestHaskellMode = cleverHaskellMode 
 {
  modeKeymap = modeKeymap Shim.mode
 }

myModetable :: ReaderT String Maybe AnyMode
myModetable = ReaderT $ \fname -> case () of 
                        _ | ".hs" `isSuffixOf` fname -> Just $ AnyMode bestHaskellMode
                        _ ->  Nothing

-- Only published actions can be run from M-x
myActions :: M.Map String [Dynamic]
myActions = (M.union defaultPublishedActions) $ M.fromList $
                      [ ("helloW", box helloWorld)
                       ,("commentR", box commentRegionB)
                      ]
            where box x = [toDyn x]

-- The list of keys that you wish to override/add to
-- the default emacs keybindings.
-- myKeys :: KList -- KList is hidden
myKeys =
    -- @write a@ returns a keymap that just outputs the action @a@.
  [ ("C-x C-t", write $ helloWorld)
  ]

-- So your keymap will be the emacs keybindings
-- 'keymap' with your additional/overriding key
-- binding definitions.
myKeyMap :: Keymap 
myKeyMap = keymap <|> makeKeymap myKeys

------------------------ User-defined functions------
-----------------------------------------------------

commentRegionB :: BufferM ()
commentRegionB = do 
  mark <- getSelectionMarkPointB
  p <- pointB
  let region = mkRegion mark p
  text <- readRegionB region
  let newText = unlines $ map ("# " ++ ) $ lines text
  replaceRegionB region newText

helloWorld :: BufferM ()
helloWorld = do
  insertN "Hello, world!"

helloWorld' :: YiM ()
helloWorld' = do 
  withBuffer $ insertN "Hello, world!"

main :: IO ()
main = yi $ defaultConfig {
                           startFrontEnd = Yi.UI.Vty.start,
                           modeTable = myModetable <|> modeTable defaultConfig,
                           configUI = (configUI defaultConfig) { configFontSize = Just 10 },
                           defaultKm = myKeyMap,
                           publishedActions = myActions
                          }