-- Copyright (c) 2019 The DAML Authors. All rights reserved.
-- SPDX-License-Identifier: Apache-2.0

{-# LANGUAGE DuplicateRecordFields #-}
{-# LANGUAGE RankNTypes            #-}

module Development.IDE.LSP.Notifications
    ( setHandlersNotifications
    ) where

import           Development.IDE.LSP.Server
import qualified Language.Haskell.LSP.Core        as LSP
import           Language.Haskell.LSP.Types
import qualified Language.Haskell.LSP.Types       as LSP

import           Development.IDE.Core.IdeConfiguration
import           Development.IDE.Core.Service
import           Development.IDE.Types.Location
import           Development.IDE.Types.Logger

import           Control.Monad.Extra
import           Data.Foldable                    as F
import           Data.Maybe
import qualified Data.HashSet                     as S
import qualified Data.Text                        as Text

import           Development.IDE.Core.FileStore   (setSomethingModified, setFileModified)
import           Development.IDE.Core.FileExists  (modifyFileExists)
import           Development.IDE.Core.OfInterest


whenUriFile :: Uri -> (NormalizedFilePath -> IO ()) -> IO ()
whenUriFile uri act = whenJust (LSP.uriToFilePath uri) $ act . toNormalizedFilePath'

setHandlersNotifications :: PartialHandlers c
setHandlersNotifications = PartialHandlers $ \WithMessage{..} x -> return x
    {LSP.didOpenTextDocumentNotificationHandler = withNotification (LSP.didOpenTextDocumentNotificationHandler x) $
        \_ ide (DidOpenTextDocumentParams TextDocumentItem{_uri,_version}) -> do
            updatePositionMapping ide (VersionedTextDocumentIdentifier _uri (Just _version)) (List [])
            whenUriFile _uri $ \file -> do
                modifyFilesOfInterest ide (S.insert file)
                setFileModified ide file
                logInfo (ideLogger ide) $ "Opened text document: " <> getUri _uri

    ,LSP.didChangeTextDocumentNotificationHandler = withNotification (LSP.didChangeTextDocumentNotificationHandler x) $
        \_ ide (DidChangeTextDocumentParams identifier@VersionedTextDocumentIdentifier{_uri} changes) -> do
            updatePositionMapping ide identifier changes
            whenUriFile _uri $ \file -> setFileModified ide file
            logInfo (ideLogger ide) $ "Modified text document: " <> getUri _uri

    ,LSP.didSaveTextDocumentNotificationHandler = withNotification (LSP.didSaveTextDocumentNotificationHandler x) $
        \_ ide (DidSaveTextDocumentParams TextDocumentIdentifier{_uri}) -> do
            whenUriFile _uri $ \file -> setFileModified ide file
            logInfo (ideLogger ide) $ "Saved text document: " <> getUri _uri

    ,LSP.didCloseTextDocumentNotificationHandler = withNotification (LSP.didCloseTextDocumentNotificationHandler x) $
        \_ ide (DidCloseTextDocumentParams TextDocumentIdentifier{_uri}) -> do
            whenUriFile _uri $ \file -> do
                modifyFilesOfInterest ide (S.delete file)
                logInfo (ideLogger ide) $ "Closed text document: " <> getUri _uri
    ,LSP.didChangeWatchedFilesNotificationHandler = withNotification (LSP.didChangeWatchedFilesNotificationHandler x) $
        \_ ide (DidChangeWatchedFilesParams fileEvents) -> do
            let events =
                    mapMaybe
                        (\(FileEvent uri ev) ->
                            (, ev /= FcDeleted) . toNormalizedFilePath'
                            <$> LSP.uriToFilePath uri
                        )
                        ( F.toList fileEvents )
            let msg = Text.pack $ show events
            logInfo (ideLogger ide) $ "Files created or deleted: " <> msg
            modifyFileExists ide events
            setSomethingModified ide

    ,LSP.didChangeWorkspaceFoldersNotificationHandler = withNotification (LSP.didChangeWorkspaceFoldersNotificationHandler x) $
        \_ ide (DidChangeWorkspaceFoldersParams events) -> do
            let add       = S.union
                substract = flip S.difference
            modifyWorkspaceFolders ide
              $ add       (foldMap (S.singleton . parseWorkspaceFolder) (_added   events))
              . substract (foldMap (S.singleton . parseWorkspaceFolder) (_removed events))
    }