From c0c3ddbd131fb670252da8c20f605987cd5c3bd7 Mon Sep 17 00:00:00 2001
From: Jun Matsushita <jun@iilab.org>
Date: Thu, 22 Nov 2018 17:32:41 +0200
Subject: [PATCH 1/2] Add onFileLoaded event #64

---
 rasa-ext-files/rasa-ext-files.cabal            |  1 +
 rasa-ext-files/src/Rasa/Ext/Files.hs           | 17 ++++++++++++++---
 .../src/Rasa/Ext/Files/Internal/Events.hs      | 18 ++++++++++++++++++
 3 files changed, 33 insertions(+), 3 deletions(-)
 create mode 100644 rasa-ext-files/src/Rasa/Ext/Files/Internal/Events.hs

diff --git a/rasa-ext-files/rasa-ext-files.cabal b/rasa-ext-files/rasa-ext-files.cabal
index 5c5285e..b6c98cd 100644
--- a/rasa-ext-files/rasa-ext-files.cabal
+++ b/rasa-ext-files/rasa-ext-files.cabal
@@ -17,6 +17,7 @@ library
   hs-source-dirs:      src
   exposed-modules:
                        Rasa.Ext.Files
+                       Rasa.Ext.Files.Internal.Events
 
   build-depends:       base >= 4.8 && < 5
                      , rasa
diff --git a/rasa-ext-files/src/Rasa/Ext/Files.hs b/rasa-ext-files/src/Rasa/Ext/Files.hs
index 72624b2..7652806 100644
--- a/rasa-ext-files/src/Rasa/Ext/Files.hs
+++ b/rasa-ext-files/src/Rasa/Ext/Files.hs
@@ -5,6 +5,10 @@
 module Rasa.Ext.Files
   ( files
   , save
+  -- Events
+  , onFileLoaded
+  , dispatchFileLoaded
+  , FileLoaded(..), Extension(..)
   ) where
 
 import qualified Data.Text.IO as TIO
@@ -101,9 +105,16 @@ setFilename fname = setBufExt $ FileInfo (Just fname)
 
 -- | Add a buffer for a file
 addFile :: String -> Y.YiString -> App ()
-addFile fname txt = do
-  newBuf <- addBuffer txt
-  bufDo_ newBuf (setFilename fname)
+addFile fname txt =
+  do
+    newBuf <- addBuffer txt
+    dispatchFileLoaded $ extOf fname newBuf
+    bufDo_ newBuf (setFilename fname)
+  where
+    extOf f buf = FileLoaded (safeExt f) buf
+    safeExt f = case FilePath.takeExtensions f of
+      ext -> Extension $ ext
+      "" -> UnknownExtension
 
 -- | Load files from command line
 loadFiles :: App ()
diff --git a/rasa-ext-files/src/Rasa/Ext/Files/Internal/Events.hs b/rasa-ext-files/src/Rasa/Ext/Files/Internal/Events.hs
new file mode 100644
index 0000000..ee1c8b6
--- /dev/null
+++ b/rasa-ext-files/src/Rasa/Ext/Files/Internal/Events.hs
@@ -0,0 +1,18 @@
+module Rasa.Ext.Files.Internal.Events where
+
+import Rasa.Ext
+
+import Control.Monad
+
+data Extension = Extension String | UnknownExtension deriving (Eq)
+
+data FileLoaded
+  = FileLoaded Extension BufRef
+
+-- | Trigger an 'App' on a 'Keypress'
+onFileLoaded :: (FileLoaded -> App result) -> App ListenerId
+onFileLoaded actionF = addListener (void <$> actionF)
+
+-- | Dispatch a 'Keypress' event.
+dispatchFileLoaded :: FileLoaded -> App ()
+dispatchFileLoaded = dispatchEvent

From 9a231bc6ec0848d4576640b22833677e188684ad Mon Sep 17 00:00:00 2001
From: Jun Matsushita <jun@iilab.org>
Date: Thu, 22 Nov 2018 17:33:25 +0200
Subject: [PATCH 2/2] Added basic validity and existence checks

---
 rasa-ext-files/rasa-ext-files.cabal  |  3 +++
 rasa-ext-files/src/Rasa/Ext/Files.hs | 20 ++++++++++++++------
 2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/rasa-ext-files/rasa-ext-files.cabal b/rasa-ext-files/rasa-ext-files.cabal
index b6c98cd..a71fef6 100644
--- a/rasa-ext-files/rasa-ext-files.cabal
+++ b/rasa-ext-files/rasa-ext-files.cabal
@@ -28,6 +28,9 @@ library
                      , text
                      , mtl
                      , yi-rope
+                     , filepath
+                     , directory
+
   default-language:    Haskell2010
 
   default-extensions:
diff --git a/rasa-ext-files/src/Rasa/Ext/Files.hs b/rasa-ext-files/src/Rasa/Ext/Files.hs
index 7652806..ba1e947 100644
--- a/rasa-ext-files/src/Rasa/Ext/Files.hs
+++ b/rasa-ext-files/src/Rasa/Ext/Files.hs
@@ -26,15 +26,20 @@ import Rasa.Ext
 import Rasa.Ext.Views
 import Rasa.Ext.Cmd
 
+import Rasa.Ext.Files.Internal.Events
+
+import qualified System.FilePath as FilePath
+import System.Directory
+
 -- | Stores filename
 data FileInfo =
-  FileInfo (Maybe String)
+  FileInfo (Maybe FilePath)
   deriving (Typeable, Show, Eq)
 
 instance Default FileInfo where
   def = FileInfo Nothing
 
-type Filename = String
+type Filename = FilePath
 
 -- | Stores File status; Clean means all changes are saved
 data FileStatus =
@@ -100,11 +105,11 @@ save = do
   setFileStatus Clean
 
 -- | Set the filename
-setFilename :: String -> BufAction ()
+setFilename :: FilePath -> BufAction ()
 setFilename fname = setBufExt $ FileInfo (Just fname)
 
 -- | Add a buffer for a file
-addFile :: String -> Y.YiString -> App ()
+addFile :: FilePath -> Y.YiString -> App ()
 addFile fname txt =
   do
     newBuf <- addBuffer txt
@@ -120,5 +125,8 @@ addFile fname txt =
 loadFiles :: App ()
 loadFiles = do
   fileNames <- liftIO getArgs
-  fileTexts <- liftIO $ traverse TIO.readFile fileNames
-  mapM_ (uncurry addFile) $ zip fileNames (Y.fromText <$> fileTexts)
+  -- Silently filter out invalid filenames or unexisting files for now
+  validFileNames <- return $ filter FilePath.isValid fileNames
+  existingFileNames <- liftIO $ filterM doesFileExist validFileNames
+  fileTexts <- liftIO $ traverse TIO.readFile existingFileNames
+  mapM_ (uncurry addFile) $ zip existingFileNames (Y.fromText <$> fileTexts)