it remembers what buffers a window has open

extensions/tabs/tabs.coffee

@@ -17,7 +17,10 @@ class Tabs extends Extension
 
     Event.on 'editor:bufferAdd', (e) =>
       path = e.details
-      return if fs.isDirectory path  # Ignore directories
+      @pane.addTab path
+
+    Event.on 'editor:bufferFocus', (e) =>
+      path = e.details
       @pane.addTab path
 
     Event.on 'editor:bufferRemove', (e) =>

src/editor.coffee

@@ -18,11 +18,6 @@ class Editor
   constructor: (path) ->
     KeyBinder.register "editor", @
 
-    # Resize editor when panes are added/removed
-    el = document.body
-    el.addEventListener 'DOMNodeInsertedIntoDocument', => @resize()
-    el.addEventListener 'DOMNodeRemovedFromDocument', => @resize()
-
     @ace = ace.edit "ace-editor"
 
     # This stuff should all be grabbed from the .atomicity dir
@@ -37,6 +32,11 @@ class Editor
 
     @addBuffer path
 
+    # Resize editor when panes are added/removed
+    el = document.body
+    el.addEventListener 'DOMNodeInsertedIntoDocument', => @resize()
+    el.addEventListener 'DOMNodeRemovedFromDocument', => @resize()
+
   modeMap:
     js: 'javascript'
     c: 'c_cpp'
@@ -119,6 +119,8 @@ class Editor
         @ace.setSession  new EditSession ''
 
   focusBuffer: (path) ->
+    return if @activePath == path
+
     @activePath = path
 
     buffer = @buffers[path] or @addBuffer path

src/event.coffee

@@ -13,7 +13,6 @@ class Event
     window.document.removeEventListener name, callback
 
   @trigger: (name, data, bubbleToApp=true) ->
-    console.log name
     if bubbleToApp and name.match /^app:/
       OSX.NSApp.triggerGlobalEvent_data name, data
       return

src/storage.coffee

@@ -0,0 +1,16 @@
+module.exports =
+class Storage
+  @get: (key, defaultValue) ->
+    try
+      object = JSON.parse(localStorage[key] ? "{}")
+    catch error
+      error.message += "\nGetting #{key}"
+      console.error(error)
+
+    object ? defaultValue
+
+  @set: (key, value) ->
+    if value == undefined
+      delete localStorage[key]
+    else
+      localStorage[key] = JSON.stringify(value.valueOf())

src/window.coffee

@@ -3,6 +3,7 @@ Extension = require 'extension'
 Event = require 'event'
 KeyBinder = require 'key-binder'
 Native = require 'native'
+Storage = require 'storage'
 
 fs = require 'fs'
 
@@ -31,6 +32,37 @@ windowAdditions =
     @loadExtensions()
     @loadKeyBindings()
 
+    @restoreEditorState()
+
+  storageKey: ->
+    "project:" + atomController.path
+
+  restoreEditorState: ->
+    storage = Storage.get @storageKey(), {}
+    @editor.addBuffer path for path in storage.openPaths ? []
+    @editor.focusBuffer storage.lastOpenedPath
+
+    # Remember what buffers were open and closed
+    Event.on "editor:bufferFocus", (e) =>
+      path = e.details
+      storage = Storage.get @storageKey(), {}
+      storage.lastOpenedPath = path.valueOf()
+      Storage.set @storageKey(), storage
+
+    Event.on "editor:bufferAdd", (e) =>
+      path = e.details
+      storage = Storage.get @storageKey(), {}
+      storage.openPaths ?= []
+      unless path.valueOf() in storage.openPaths
+        storage.openPaths.push path.valueOf()
+        Storage.set @storageKey(), storage
+
+    Event.on "editor:bufferRemove", (e) =>
+      path = e.details
+      storage = Storage.get @storageKey(), {}
+      storage.openPaths = (p for p in storage.openPaths when p != path)
+      Storage.set @storageKey(), storage
+
   loadExtensions: ->
     extension.shutdown() for extension in @extensions
     @extensions = []
@@ -69,7 +101,7 @@ windowAdditions =
     atomController.window.title = title
 
   reload: ->
-    @close()
+    atomController.close
     Native.newWindow atomController.path
 
   open: (path) ->
@@ -93,9 +125,6 @@ windowAdditions =
     parent = atomController.path.replace(/([^\/])$/, "$1/")
     child = path.replace(/([^\/])$/, "$1/")
 
-    window.x = parent
-    window.y = child
-
     # If the child is contained by the parent, it can be opened by this window
     return child.match "^" + parent