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diff --git a/Lazymail/Screen.hs b/Lazymail/Screen.hs
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+{- Lazymail interaction with curses.
+ -
+ - Copyright 2013 Raúl Benencia <rul@kalgan.cc>
+ -
+ - Licensed under the GNU GPL version 3 or higher
+ -
+ - This code is in an urgent need of a big refactoring.
+ -}
+
+module Lazymail.Screen where
+
+import Codec.MIME.Type(MIMEValue(..))
+import Control.Monad.Trans(liftIO)
+import Control.Monad.Reader
+import Control.Monad.State
+import Data.Char(toUpper)
+import Data.List(isPrefixOf)
+import System.Exit
+import UI.NCurses
+
+-- Local imports
+import Lazymail.Config
+import qualified Lazymail.Handlers as EH
+import Lazymail.Maildir
+import Lazymail.Email(lookupField, getBody, getHeaders, lookupField')
+import Lazymail.Print
+import Codec.Text.Rfc1342
+import Lazymail.State
+import Lazymail.Types
+
+{- This function is the nexus between Curses and IO -}
+entryPoint :: Lazymail ()
+entryPoint = do
+  st <- get
+  cfg <- ask
+  maildirs <- liftIO $ do
+    mds <- getMaildirsRecursively $ basePath st
+    (filterMaildirsHook cfg) mds
+  formattedMDs <- EH.formatMaildirModeRows st maildirs
+  let mdState = (maildirState st) { detectedMDs = formattedMDs }
+  liftIO $ runCurses $ runStateT (runReaderT startCurses cfg) (st { maildirState = mdState })
+  return ()
+
+{- Initial point of screen related functions. Get the number of rows,
+ - colors, and start drawing the modes -}
+startCurses :: LazymailCurses ()
+startCurses = do
+  st <- get
+  cfg <- ask
+  (=<<) put $ liftCurses $ do
+    setEcho False
+    setCursorMode CursorInvisible
+    w <- defaultWindow
+    (rows, cols) <- screenSize
+    basColID <- newColorID (fst . baseColor $ cfg) (snd . baseColor $ cfg) 1
+    selColID <- newColorID (fst . selectionColor $ cfg) (snd . selectionColor $ cfg) 2
+    staColID <- newColorID (fst . statusBarColor $ cfg) (snd . statusBarColor $ cfg) 3
+    heaColID <- newColorID (fst . headerColor $ cfg) (snd . headerColor $ cfg) 4
+    newColID <- newColorID (fst . newEmailColor $ cfg) (snd . newEmailColor $ cfg) 5
+    let style = ColorStyle basColID selColID staColID heaColID newColID
+    return $ st { screenRows = fromIntegral $ rows - 1
+                , screenColumns = fromIntegral $ cols
+                , colorStyle = style }
+  resetScrollBuffer
+  screenLoop
+
+{- This function will loop til the user decides to leave -}
+screenLoop :: LazymailCurses ()
+screenLoop = do
+  w <- liftCurses $ defaultWindow
+  cfg <- ask
+  get >>=  \st ->
+    (liftCurses . (updateWindow w) $ runStateT (runReaderT performUpdate cfg) st) >>= put . snd
+  liftCurses $ render
+  handleEvent
+  get >>= \st -> if (not . exitRequested) st
+                 then screenLoop
+                 else return ()
+
+{- Perform the screen update, by cleaning it first. -}
+performUpdate :: LazymailUpdate LazymailState
+performUpdate = do
+  st <- get
+  liftUpdate $ clearMain (scrRowsAsInteger st) (screenColumns st)
+  drawMode (mode st)
+  drawStatus
+  get
+
+{- Pattern match on the received mode and draw it in the screen. -}
+drawMode :: Mode -> LazymailUpdate ()
+drawMode MaildirMode = get >>= \st -> drawSelectionList $ scrollBufferMD . maildirState $ st
+drawMode IndexMode   = get >>= \st -> drawSelectionList $ scrollBufferIn . indexState $ st
+drawMode EmailMode   = drawEmailHelper
+
+{- Draw a scrollable selection list -}
+drawSelectionList [] = resetCurrentRow
+drawSelectionList ((path, str):mds) = do
+  st <- get
+  (=<<) put $ liftUpdate $ do
+    moveCursor (curRowAsInteger st) (colPadAsInteger st)
+    if (selectedRow st == currentRow st)
+      then do
+        setColor $ selectionColorID . colorStyle $ st
+        drawString $ normalizeLen (screenColumns st) str
+        setColor $ baseColorID . colorStyle $ st
+        case (mode st) of
+          MaildirMode -> do
+            let mst = (maildirState st) { selectedMD = path }
+            return $ st { maildirState = mst }
+          IndexMode   -> do
+            let ist = (indexState st) { selectedEmailPath = path }
+            return $ st { indexState = ist }
+      else do
+        drawSimpleRow st path str
+        return st
+
+  st <- get
+  let limit = if statusBar st then (screenRows st) - 1 else screenRows st
+  if currentRow st < limit
+    then do
+      incrementCurrentRow
+      drawSelectionList mds
+    else
+      resetCurrentRow
+
+drawSimpleRow st path str | (mode st) == MaildirMode = drawString $ normalizeLen (screenColumns st) str
+                          | (mode st) == IndexMode   =
+  if isNew path
+  then do
+    setColor $ newEmailColorID . colorStyle $ st
+    drawCroppedString st str
+    setColor $ baseColorID . colorStyle $ st
+  else
+    drawCroppedString st str
+
+{- Empty the whole window. Useful when changing modes. -}
+clearMain rows columns = do
+  drawEmptyLine 0
+  moveCursor 0 0
+  where
+    drawEmptyLine currentRow = do
+      moveCursor currentRow 0
+      drawString $ replicate (columns) ' '
+      when (currentRow < rows - 1) $ drawEmptyLine $ currentRow + 1
+
+{- Helper function of drawMode -}
+drawEmailHelper = do
+  drawEmailHeaders
+
+  st <- get
+  let est = emailState st
+  put $ st { emailState = est { bodyStartRow = (currentRow st ) } }
+  let body = getBody $ currentEmail . emailState $ st
+  let maxRows = if statusBar st then (scrRowsAsInteger st) - 1 else scrRowsAsInteger st
+  liftUpdate $
+    drawBody (curRowAsInteger st) (colPadAsInteger st) maxRows $
+      drop (scrollRowEm est) $ emailLines est
+  resetCurrentRow
+
+{- Draw the email headers -}
+drawEmailHeaders = do
+  st <- get
+  cfg <- ask
+  let hs = getHeaders $ currentEmail . emailState $ st
+  let parsedHeaders = parseHeaders hs 0 $ headersToShow cfg
+
+  liftUpdate $ do
+    setColor $ headerColorID . colorStyle $ st
+    drawHeaders st (curRowAsInteger st) parsedHeaders
+    setColor $ baseColorID . colorStyle $ st
+  put $ st { currentRow = 1 + (length parsedHeaders) + (currentRow st) }
+
+  where
+    parseHeaders _ _ [] = []
+    parseHeaders headers row (h:hs)= do
+      let field = lookupField' h headers
+      case field of
+        Nothing -> parseHeaders headers row hs
+        Just f -> let p = capitalize h ++ ": " ++ (ppField f)
+                  in p:parseHeaders headers (row + 1) hs
+
+    capitalize str = (toUpper . head $ str):(tail str)
+    drawHeaders _ _ []      = return ()
+    drawHeaders st row (h:hs) = do
+      moveCursor row (colPadAsInteger st)
+      drawCroppedString st h
+      drawHeaders st (row + 1) hs
+
+{- Draw the email body -}
+drawBody _ _ _ [] = return ()
+drawBody row col maxRows (xs:xss) = do
+  moveCursor row col
+  drawString xs
+  when (row <  maxRows) $ drawBody (row + 1) col maxRows  xss
+
+{- Draw a status line with the current mode and other stuff -}
+drawStatus  = do
+  st <- get
+  liftUpdate $ do
+    moveCursor (scrRowsAsInteger st) 0
+    setColor $ statusBarColorID . colorStyle $ st
+    drawString $ normalizeLen (screenColumns st - 1)$ concat $ drawStatusHelper (mode st) st -- Can't write in the last char - ncurses bug
+    setColor $ baseColorID . colorStyle $ st
+
+{- Status bar string for Maildir mode -}
+drawStatusHelper MaildirMode st =
+  ["Maildir listing - "
+  , "(", show ((selectedRow st) + (scrollRowMD . maildirState $ st) + 1), "/"
+  ,  show (length $ detectedMDs . maildirState $ st), ")"]
+
+{- Status bar string for Index mode -}
+drawStatusHelper IndexMode st =
+  ["mode: Index - "
+  , "(", show ((selectedRow st) + (scrollRowIn . indexState $ st) + 1), "/"
+  ,  show (currentInLen . indexState $ st), ")"]
+
+{- Status bar string for Email mode -}
+drawStatusHelper EmailMode st = ["mode: Email"]
+
+{- Handle an event
+ - TODO: Handle the events in a cleaner way. -}
+handleEvent :: LazymailCurses ()
+handleEvent = loop where
+  loop = do
+    w <- liftCurses $ defaultWindow
+    ev <- liftCurses $ getEvent w Nothing
+    st <- get
+    case ev of
+      Nothing  -> loop
+      Just ev' ->
+        case ev' of
+          EventCharacter 'q'            -> EH.previousMode (mode st)
+
+          EventSpecialKey KeyUpArrow    -> EH.decSelectedRow (mode st)
+          EventCharacter 'k'            -> EH.decSelectedRow (mode st)
+
+          EventSpecialKey KeyDownArrow  -> EH.incSelectedRow (mode st)
+          EventCharacter 'j'            -> EH.incSelectedRow (mode st)
+
+          EventCharacter '\n'           -> EH.changeMode (mode st)
+          EventSpecialKey KeyRightArrow -> EH.changeMode (mode st)
+
+          _ ->  loop
+
+{- Reset the current row to the beginning -}
+resetCurrentRow = (=<<) put $ get >>= \st -> return $ st { currentRow = 0 }
+
+{- Advance the current row. Useful when drawing modes -}
+incrementCurrentRow = (=<<) put $ get >>= \st -> return $ st { currentRow = (currentRow st) + 1 }
+
+{- Put the scroll at the top -}
+resetScrollBuffer = do
+  st <- get
+  case (mode st) of
+    MaildirMode -> do
+      let mst = (maildirState st) {
+            scrollBufferMD = EH.scrollCrop 0 (screenRows st) $ detectedMDs . maildirState $ st }
+      put st { maildirState = mst}
+    IndexMode -> do
+      let ist = (indexState st) {
+            scrollBufferIn = EH.formatIndexModeRows st $  EH.scrollCrop 0 (screenRows st) $ selectedEmails . indexState $ st }
+      put st { indexState = ist }
+
+drawCroppedString st str = drawString $ normalizeLen (screenColumns st) str
+
+-- The type system complains if I want to use the same function for diferents monads
+liftCurses = lift . lift
+liftUpdate  = lift . lift