{-# OPTIONS_GHC -XFlexibleContexts -XTypeSynonymInstances -XMultiParamTypeClasses
    -XScopedTypeVariables #-}
-----------------------------------------------------------------------------
--
-- Module      :  IDE.Core.State
-- Copyright   :  (c) Juergen Nicklisch-Franken, Hamish Mackenzie
-- License     :  GNU-GPL
--
-- Maintainer  :  <maintainer at leksah.org>
-- Stability   :  provisional
-- Portability :  portable
--
-- | The core state of ide. This module is imported from every other module,
-- | and all data structures of the state are declared here, to avoid circular
-- | module dependencies.
--
-------------------------------------------------------------------------------

module IDE.Core.State (
    IDEObject
,   IDEEditor
,   IDE(..)
,   window
,   errorRefs
,   breakpointRefs
,   contextRefs
,   currentError
,   currentBreak
,   currentContext
,   setCurrentError
,   setCurrentBreak
,   setCurrentContext
,   isInterpreting

,   IDEState(..)
,   isStartingOrClosing
,   IDERef
,   IDEM
,   IDEAction
,   IDEEvent(..)

,   triggerEventIDE

-- * Convenience methods for accesing the IDE State
,   readIDE
,   modifyIDE
,   modifyIDE_
,   withIDE
,   getIDE

,   reifyIDE
,   reflectIDE
,   catchIDE
,   postSyncIDE
,   postAsyncIDE

,   newPane

,   ideMessage
,   logMessage
,   sysMessage
,   MessageLevel(..)

,   withoutRecordingDo
,   activatePane
,   deactivatePane
,   deactivatePaneIfActive
,   closePane

,   getCandyState
,   setCandyState
,   getForgetSession

,   getSBSpecialKeys
,   getSBActivePane
,   getSBActivePackage
,   getSBErrors
,   getStatusbarIO
,   getStatusbarLC

,   getBackgroundBuildToggled
,   setBackgroundBuildToggled
,   getBackgroundLinkToggled
,   setBackgroundLinkToggled
,   getDebugToggled
,   setDebugToggled

,   getRecentFiles
,   getRecentPackages
,   controlIsPressed

,   Session

,   module IDE.Core.Types
,   module Graphics.UI.Frame.Panes
,   module Graphics.UI.Frame.ViewFrame
,   module IDE.Exception

) where

import Graphics.UI.Gtk hiding (get)
import Graphics.UI.Gtk.SourceView.SourceView ()
import Graphics.UI.Gtk.Gdk.Enums (Modifier(..))
import qualified Graphics.UI.Gtk.Gdk.Events as G (Event(..))
import Data.Map (Map)
import qualified Data.Map as Map
import Data.IORef
import Control.Monad.Reader hiding (liftIO)
import qualified Control.Monad.Reader (liftIO)
import Control.Monad.Trans
import HscTypes hiding (liftIO)
import Data.Unique
import Control.Exception
import Prelude hiding (catch)

import IDE.Core.Types
import Graphics.UI.Frame.Panes
import Graphics.UI.Frame.ViewFrame hiding (notebookInsertOrdered)
import qualified Graphics.UI.Frame.ViewFrame as VF (notebookInsertOrdered)
import IDE.Exception
import Control.Event
import System.IO
import System.Process (ProcessHandle(..))
import IDE.Tool (ToolState(..))
import Data.Maybe (isJust)

-- this should not be repeated here, why is it necessary?
instance MonadIO Ghc where
  liftIO ioA = Ghc $ \_ -> ioA

ideMessage :: MessageLevel -> String -> IDEAction
ideMessage level str = do
    triggerEventIDE (LogMessage (str ++ "\n") LogTag)
    liftIO $ sysMessage level str

logMessage :: String -> LogTag -> IDEAction
logMessage str tag = do
    triggerEventIDE (LogMessage (str ++ "\n") tag)
    return ()

sysMessage :: MonadIO m =>  MessageLevel -> String -> m ()
sysMessage ml str = liftIO $ do
    putStrLn str
    hFlush stdout

data MessageLevel = Silent | Normal | High
    deriving (Eq,Ord,Show)

class IDEObject alpha
class IDEObject o => IDEEditor o

-- ---------------------------------------------------------------------
-- IDE State
--

--
-- | The IDE state
--
data IDE            =  IDE {
    frameState      ::   FrameState IDEM         -- ^ state of the windows framework
,   recentPanes     ::   [PaneName]
,   specialKeys     ::   SpecialKeyTable IDERef  -- ^ a structure for emacs like keystrokes
,   specialKey      ::   SpecialKeyCons IDERef   -- ^ the first of a double keystroke
,   candy           ::   CandyTable              -- ^ table for source candy
,   prefs           ::   Prefs                   -- ^ configuration preferences
,   activePack      ::   Maybe IDEPackage
,   projFilesCache  ::   Map FilePath Bool       -- ^ caches property that a buffer belongs to a project
,   allLogRefs      ::   [LogRef]
,   currentEBC      ::   (Maybe LogRef, Maybe LogRef, Maybe LogRef)
,   currentHist     ::   Int
,   accessibleInfo  ::   (Maybe (PackageScope))     -- ^  the world scope
,   currentInfo     ::   (Maybe (PackageScope,PackageScope))
                                                -- ^ the first is for the current package,
                                                --the second is the scope in the current package
,   handlers        ::   Map String [(Unique, IDEEvent -> IDEM IDEEvent)]
                                                -- ^ event handling table
,   currentState    ::   IDEState
,   guiHistory      ::   (Bool,[GUIHistory],Int)
,   findbar         ::   (Bool,Maybe (Toolbar,ListStore String))
,   toolbar         ::   (Bool,Maybe Toolbar)
,   recentFiles     ::   [FilePath]
,   recentPackages  ::   [FilePath]
,   runningTool     ::   Maybe ProcessHandle
,   ghciState       ::   Maybe ToolState
,   completion      ::   Maybe CompletionWindow
} --deriving Show

-- Main window is just the first one in the list
window = head . windows


errorRefs :: IDE -> [LogRef]
errorRefs = (filter ((\t -> t == ErrorRef || t == WarningRef) . logRefType)) . allLogRefs

breakpointRefs :: IDE -> [LogRef]
breakpointRefs = (filter ((== BreakpointRef) . logRefType)) . allLogRefs

contextRefs :: IDE -> [LogRef]
contextRefs = (filter ((== ContextRef) . logRefType)) . allLogRefs

currentError     = (\(e,_,_)-> e) . currentEBC
currentBreak     = (\(_,b,_)-> b) . currentEBC
currentContext   = (\(_,_,c)-> c) . currentEBC

setCurrentError e = do
    modifyIDE_ (\ide -> ide{currentEBC = (e, currentBreak ide, currentContext ide)})
    triggerEventIDE (CurrentErrorChanged e) >> return ()
setCurrentBreak b = do
    modifyIDE_ (\ide -> ide{currentEBC = (currentError ide, b, currentContext ide)})
    triggerEventIDE (CurrentBreakChanged b) >> return ()
setCurrentContext c = modifyIDE_ (\ide -> ide{currentEBC = (currentError ide, currentBreak ide, c)})


data IDEState =
        IsStartingUp
    |   IsShuttingDown
    |   IsRunning
    |   IsFlipping TreeView
    |   IsCompleting Connections

isStartingOrClosing ::  IDEState -> Bool
isStartingOrClosing IsStartingUp    = True
isStartingOrClosing IsShuttingDown  = True
isStartingOrClosing _               = False

isInterpreting :: IDEM Bool
isInterpreting = do
    readIDE ghciState >>= \mb -> return (isJust mb)


data IDEEvent  =
        CurrentInfo
    |   ActivePack
    |   SelectInfo String
    |   SelectIdent Descr
    |   LogMessage String LogTag
    |   RecordHistory GUIHistory
    |   Sensitivity [(SensitivityMask,Bool)]
    |   DescrChoice [Descr]
    |   SearchMeta String
    |   LoadSession FilePath
    |   SaveSession FilePath
    |   UpdateRecent
    |   VariablesChanged
    |   ErrorChanged
    |   CurrentErrorChanged (Maybe LogRef)
    |   BreakpointChanged
    |   CurrentBreakChanged (Maybe LogRef)
    |   TraceChanged
    |   GetTextPopup (Maybe (IDERef -> Menu -> IO ()))
--
-- | A mutable reference to the IDE state
--
type IDERef = IORef IDE

instance Event IDEEvent String where
    getSelector CurrentInfo             =   "CurrentInfo"
    getSelector ActivePack              =   "ActivePack"
    getSelector (LogMessage _ _)        =   "LogMessage"
    getSelector (SelectInfo _)          =   "SelectInfo"
    getSelector (SelectIdent _)         =   "SelectIdent"
    getSelector (RecordHistory _)       =   "RecordHistory"
    getSelector (Sensitivity _)         =   "Sensitivity"
    getSelector (DescrChoice _)         =   "DescrChoice"
    getSelector (SearchMeta _)          =   "SearchMeta"
    getSelector (LoadSession _)         =   "LoadSession"
    getSelector (SaveSession _)         =   "SaveSession"
    getSelector UpdateRecent            =   "UpdateRecent"
    getSelector VariablesChanged        =   "VariablesChanged"
    getSelector ErrorChanged            =   "ErrorChanged"
    getSelector (CurrentErrorChanged _) =   "CurrentErrorChanged"
    getSelector BreakpointChanged       =   "BreakpointChanged"
    getSelector (CurrentBreakChanged _) =   "CurrentBreakChanged"
    getSelector TraceChanged            =   "TraceChanged"
    getSelector (GetTextPopup _)        =   "GetTextPopup"

instance EventSource IDERef IDEEvent IDEM String where
    canTriggerEvent o "CurrentInfo"     =   True
    canTriggerEvent o "ActivePack"      =   True
    canTriggerEvent o "LogMessage"      =   True
    canTriggerEvent o "SelectInfo"      =   True
    canTriggerEvent o "SelectIdent"     =   True
    canTriggerEvent o "RecordHistory"   =   True
    canTriggerEvent o "Sensitivity"     =   True
    canTriggerEvent o "DescrChoice"     =   True
    canTriggerEvent o "SearchMeta"      =   True
    canTriggerEvent o "LoadSession"     =   True
    canTriggerEvent o "SaveSession"     =   True
    canTriggerEvent o "UpdateRecent"    =   True
    canTriggerEvent o "VariablesChanged" =   True
    canTriggerEvent o "ErrorChanged"    =   True
    canTriggerEvent o "CurrentErrorChanged" = True
    canTriggerEvent o "BreakpointChanged" = True
    canTriggerEvent o "CurrentBreakChanged" = True
    canTriggerEvent o "TraceChanged"    = True
    canTriggerEvent o "GetTextPopup"    = True
    canTriggerEvent _ _                 =   False

    getHandlers ideRef = do
        ide <- liftIO $ readIORef ideRef
        return (handlers ide)

    setHandlers ideRef nh = do
        ide <- liftIO $ readIORef ideRef
        liftIO $ writeIORef ideRef (ide {handlers= nh})

    myUnique _ = do
        liftIO $ newUnique

instance EventSelector String

triggerEventIDE :: IDEEvent -> IDEM IDEEvent
triggerEventIDE e = ask >>= \ideR -> triggerEvent ideR e

--
-- | A reader monad for a mutable reference to the IDE state
--
type IDEM = ReaderT IDERef IO

reifyIDE :: (IDERef -> IO a) -> IDEM a
reifyIDE = ReaderT

reflectIDE :: IDEM a -> IDERef -> IO a
reflectIDE c ideR = runReaderT c ideR

catchIDE :: Exception e	=> IDEM a -> (e -> IO a) -> IDEM a
catchIDE block handler = reifyIDE (\ideR -> catch (reflectIDE block ideR) handler)

postSyncIDE :: IDEM a -> IDEM a
postSyncIDE f = reifyIDE (\ideR -> postGUISync (reflectIDE f ideR))

postAsyncIDE :: IDEM () -> IDEM ()
postAsyncIDE f = reifyIDE (\ideR -> postGUIAsync (reflectIDE f ideR))

newPane :: RecoverablePane alpha beta IDEM  =>
    PanePath ->
    Notebook ->
    (PanePath -> Notebook -> Window -> IDERef -> IO (alpha,Connections)) ->
    IDEM alpha
newPane panePath notebook builder = do
    windows <- getWindows
    (buf,cids)  <-  reifyIDE (\ideR -> builder panePath notebook (head windows) ideR)
    VF.notebookInsertOrdered notebook (getTopWidget buf) (paneName buf) Nothing
    addPaneAdmin buf cids panePath
    liftIO $ do
        widgetShowAll (getTopWidget buf)
        widgetGrabFocus (getTopWidget buf)
        bringPaneToFront buf
    return buf

--
-- | A shorthand for a reader monad for a mutable reference to the IDE state
--   which does not return a value
--
type IDEAction = IDEM ()

instance PaneMonad IDEM where
    getFrameState   =   readIDE frameState
    setFrameState v =   modifyIDE_ (\ide -> ide{frameState = v})
    runInIO f       =   reifyIDE (\ideRef -> return (\v -> reflectIDE (f v) ideRef))
    panePathForGroup id =   do
        prefs  <- readIDE prefs
        case id `lookup` (categoryForPane prefs) of
            Just group -> case group `lookup`  (pathForCategory prefs) of
                            Nothing -> return (defaultPath prefs)
                            Just p  -> return p
            Nothing    -> return (defaultPath prefs)


-- ---------------------------------------------------------------------
-- Convenience methods for accesing the IDE State
--

-- | Read an attribute of the contents
readIDE :: (IDE -> beta) -> IDEM beta
readIDE f = do
    e <- ask
    liftIO $ liftM f (readIORef e)

-- | Modify the contents, using an IO action.
modifyIDE_ :: (IDE -> IDE) -> IDEM ()
modifyIDE_ f = let f' a  = (f a,()) in do
    e <- ask
    liftIO (atomicModifyIORef e f')

-- | Variation on modifyIDE_ that lets you return a value
modifyIDE :: (IDE -> (IDE,beta)) -> IDEM beta
modifyIDE f = do
    e <- ask
    liftIO (atomicModifyIORef e f)

withIDE :: (IDE -> IO alpha) -> IDEM alpha
withIDE f = do
    e <- ask
    liftIO $ f =<< readIORef e

getIDE :: IDEM(IDE)
getIDE = do
    e <- ask
    st <- liftIO $ readIORef e
    return st

withoutRecordingDo :: IDEAction -> IDEAction
withoutRecordingDo act = do
    (b,l,n) <- readIDE guiHistory
    if not b then do
        modifyIDE_ (\ide -> ide{guiHistory = (True,l,n)})
        act
        (b,l,n) <- readIDE guiHistory
        modifyIDE_ (\ide -> ide{guiHistory = (False,l,n)})
        else act

-- ---------------------------------------------------------------------
-- Activating and deactivating Panes.
-- This is here and not in Views because it needs some dependencies
-- (e.g. Events for history)
--

activatePane :: Pane alpha IDEM => alpha -> Connections -> IDEAction
activatePane pane conn = do
    mbAP <- getActivePane
    case mbAP of
        Just (pn,_) | pn == paneName pane -> return ()
        _  -> do
            deactivatePaneWithout
            sb <- getSBActivePane
            liftIO $ statusbarPop sb 1
            liftIO $ statusbarPush sb 1 (paneName pane)
            liftIO $ bringPaneToFront pane
            setActivePane (Just (paneName pane,conn))
            trigger (Just (paneName pane)) (case mbAP of
                                                    Nothing -> Nothing
                                                    Just (pn,_) -> Just pn)
            modifyIDE_ (\ide -> ide{recentPanes =
                paneName pane : filter (/= paneName pane) (recentPanes ide)})
            return ()

trigger :: Maybe String -> Maybe String -> IDEAction
trigger s1 s2 = do
    triggerEventIDE (RecordHistory ((PaneSelected s1), PaneSelected s2))
    triggerEventIDE (Sensitivity [(SensitivityEditor, False)])
    return ()

deactivatePane :: IDEAction
deactivatePane = do
    mbAP    <-  getActivePane
    case mbAP of
        Nothing      -> return ()
        Just (pn, _) -> do
            deactivatePaneWithout
            triggerEventIDE (RecordHistory (PaneSelected Nothing,
                PaneSelected (Just pn)))
            triggerEventIDE (Sensitivity [(SensitivityEditor, False)])
            return ()

deactivatePaneWithout :: IDEAction
deactivatePaneWithout = do
    sb <- getSBActivePane
    liftIO $ statusbarPop sb 1
    liftIO $ statusbarPush sb 1 ""
    mbAP    <-  getActivePane
    case mbAP of
        Just (_,signals) -> liftIO $do
            signalDisconnectAll signals
        Nothing -> return ()
    setActivePane Nothing

deactivatePaneIfActive :: Pane alpha IDEM  => alpha -> IDEAction
deactivatePaneIfActive pane = do
    mbActive <- getActivePane
    case mbActive of
        Nothing -> return ()
        Just (n,_) -> if n == paneName pane
                        then deactivatePane
                        else return ()

closePane :: Pane alpha IDEM  => alpha -> IDEM Bool
closePane pane = do
    (panePath,_)    <-  guiPropertiesFromName (paneName pane)
    nb              <-  getNotebook panePath
    mbI             <-  liftIO $notebookPageNum nb (getTopWidget pane)
    case mbI of
        Nothing ->  liftIO $ do
            throwIDE ("notebook page not found: unexpected " ++ paneName pane ++ " " ++ show panePath)
            return False
        Just i  ->  do
            deactivatePaneIfActive pane
            liftIO $ do
                notebookRemovePage nb i
                widgetDestroy (getTopWidget pane)
            removePaneAdmin pane
            modifyIDE_ (\ide -> ide{recentPanes = filter (/= paneName pane) (recentPanes ide)})
            return True

-- get widget elements (menu & toolbar)

getCandyState :: PaneMonad alpha => alpha Bool
getCandyState = do
    ui <- getUIAction "ui/menubar/_Configuration/Source Candy" castToToggleAction
    liftIO $toggleActionGetActive ui

setCandyState :: PaneMonad alpha => Bool -> alpha ()
setCandyState b = do
    ui <- getUIAction "ui/menubar/_Configuration/Source Candy" castToToggleAction
    liftIO $toggleActionSetActive ui b

getForgetSession :: PaneMonad alpha => alpha  (Bool)
getForgetSession = do
    ui <- getUIAction "ui/menubar/_Session/Forget Session" castToToggleAction
    liftIO $toggleActionGetActive ui

getMenuItem :: String -> IDEM MenuItem
getMenuItem path = do
    uiManager' <- getUiManager
    mbWidget   <- liftIO $ uiManagerGetWidget uiManager' path
    case mbWidget of
        Nothing     -> throwIDE ("State.hs>>getMenuItem: Can't find ui path " ++ path)
        Just widget -> return (castToMenuItem widget)

getBackgroundBuildToggled :: PaneMonad alpha => alpha  (Bool)
getBackgroundBuildToggled = do
    ui <- getUIAction "ui/toolbar/BuildToolItems/BackgroundBuild" castToToggleAction
    liftIO $ toggleActionGetActive ui

setBackgroundBuildToggled :: PaneMonad alpha => Bool -> alpha ()
setBackgroundBuildToggled b = do
    ui <- getUIAction "ui/toolbar/BuildToolItems/BackgroundBuild" castToToggleAction
    liftIO $ toggleActionSetActive ui b

getBackgroundLinkToggled :: PaneMonad alpha => alpha  (Bool)
getBackgroundLinkToggled = do
    ui <- getUIAction "ui/toolbar/BuildToolItems/BackgroundLink" castToToggleAction
    liftIO $ toggleActionGetActive ui

setBackgroundLinkToggled :: PaneMonad alpha => Bool -> alpha ()
setBackgroundLinkToggled b = do
    ui <- getUIAction "ui/toolbar/BuildToolItems/BackgroundLink" castToToggleAction
    liftIO $ toggleActionSetActive ui b

getDebugToggled :: PaneMonad alpha => alpha  (Bool)
getDebugToggled = do
    ui <- getUIAction "ui/toolbar/BuildToolItems/Debug" castToToggleAction
    liftIO $ toggleActionGetActive ui

setDebugToggled :: PaneMonad alpha => Bool -> alpha ()
setDebugToggled b = do
    ui <- getUIAction "ui/toolbar/BuildToolItems/Debug" castToToggleAction
    liftIO $ toggleActionSetActive ui b

getRecentFiles , getRecentPackages :: IDEM MenuItem
getRecentFiles    = getMenuItem "ui/menubar/_File/_Recent Files"
getRecentPackages = getMenuItem "ui/menubar/_Package/_Recent Packages"

-- (toolbar)

getSBSpecialKeys :: PaneMonad alpha => alpha Statusbar
getSBSpecialKeys   = widgetGet ["Leksah Main Window", "topBox","statusBox","statusBarSpecialKeys"] castToStatusbar

getSBActivePane :: PaneMonad alpha => alpha Statusbar
getSBActivePane    = widgetGet ["Leksah Main Window", "topBox","statusBox","statusBarActivePane"] castToStatusbar

getSBActivePackage :: PaneMonad alpha => alpha Statusbar
getSBActivePackage = widgetGet ["Leksah Main Window", "topBox","statusBox","statusBarActiveProject"] castToStatusbar

getSBErrors :: PaneMonad alpha => alpha Statusbar
getSBErrors        = widgetGet ["Leksah Main Window", "topBox","statusBox","statusBarErrors"] castToStatusbar

getStatusbarIO :: PaneMonad alpha => alpha Statusbar
getStatusbarIO     =  widgetGet ["Leksah Main Window", "topBox","statusBox","statusBarInsertOverwrite"] castToStatusbar

getStatusbarLC :: PaneMonad alpha => alpha Statusbar
getStatusbarLC     = widgetGet ["Leksah Main Window", "topBox","statusBox","statusBarLineColumn"] castToStatusbar

controlIsPressed :: G.Event -> Bool
controlIsPressed (G.Button _ _ _ _ _ mods _ _ _) | Control `elem` mods = True
controlIsPressed _                                                   = False