yi-0.6.1: Yi/File.hs

module Yi.File 
 (
  -- * File-based actions
  viWrite, viWriteTo, viSafeWriteTo,
  fwriteE,        -- :: YiM ()
  fwriteBufferE,  -- :: BufferM ()
  fwriteAllE,     -- :: YiM ()
  fwriteToE,      -- :: String -> YiM ()
  backupE,        -- :: FilePath -> YiM ()
  revertE,        -- :: YiM ()

  -- * Helper functions
  setFileName,
 ) where

import Data.Time
import Control.Monad.Trans
import Prelude (filter)
import Yi.Core
import Yi.Buffer (file)
import Control.Monad.State (gets)
import System.Directory
import System.IO.UTF8 as UTF8
import System.FilePath
import System.FriendlyPath
import qualified Data.Rope as R

-- | Revert to the contents of the file on disk
revertE :: YiM ()
revertE = do
            mfp <- withBuffer $ gets file
            case mfp of
                     Just fp -> do
                             now <- io getCurrentTime
                             s <- liftIO $ UTF8.readFile fp
                             withBuffer $ revertB s now
                             msgEditor ("Reverted from " ++ show fp)
                     Nothing -> do
                                msgEditor "Can't revert, no file associated with buffer."
                                return ()

-- | Try to write a file in the manner of vi\/vim
-- Need to catch any exception to avoid losing bindings
viWrite :: YiM ()
viWrite = do
    mf <- withBuffer $ gets file
    case mf of
        Nothing -> errorEditor "no file name associate with buffer"
        Just f  -> do
            bufInfo <- withBuffer bufInfoB
            let s   = bufInfoFileName bufInfo
            fwriteE
            msgEditor $ show f ++ " " ++ show s ++ " written"

-- | Try to write to a named file in the manner of vi\/vim
viWriteTo :: String -> YiM ()
viWriteTo f = do
    bufInfo <- withBuffer bufInfoB
    let s   = bufInfoFileName bufInfo
    fwriteToE f
    msgEditor $ show f++" "++show s ++ " written"

-- | Try to write to a named file if it doesn't exist. Error out if it does.
viSafeWriteTo :: String -> YiM ()
viSafeWriteTo f = do
    existsF <- liftIO $ doesFileExist f
    if existsF
       then errorEditor $ f ++ ": File exists (add '!' to override)"
       else viWriteTo f

-- | Write current buffer to disk, if this buffer is associated with a file
fwriteE :: YiM ()
fwriteE = fwriteBufferE =<< gets currentBuffer

-- | Write a given buffer to disk if it is associated with a file.
fwriteBufferE :: BufferRef -> YiM ()
fwriteBufferE bufferKey = 
  do nameContents <- withGivenBuffer bufferKey ((,) <$> gets file <*> streamB Forward 0)
     case nameContents of
       (Just f, contents) -> do now <- io getCurrentTime
                                withGivenBuffer bufferKey (markSavedB now)
                                liftIO $ R.writeFile f contents
       (Nothing, _c)      -> msgEditor "Buffer not associated with a file"

-- | Write current buffer to disk as @f@. The file is also set to @f@
fwriteToE :: String -> YiM ()
fwriteToE f = do 
    b <- gets currentBuffer
    setFileName b f
    fwriteBufferE b
    

-- | Write all open buffers
fwriteAllE :: YiM ()
fwriteAllE = 
  do allBuffs <- gets bufferSet
     let modifiedBuffers = filter (not . isUnchangedBuffer) allBuffs
     mapM_ fwriteBufferE (fmap bkey modifiedBuffers)

-- | Make a backup copy of file
backupE :: FilePath -> YiM ()
backupE = error "backupE not implemented"


-- | Associate buffer with file; canonicalize the given path name.
setFileName :: BufferRef -> FilePath -> YiM ()
setFileName b filename = do
  cfn <- liftIO $ userToCanonPath filename
  withGivenBuffer b $ putA identA $ Right cfn