UI improvements

ui/component/ClosableMenu.gd

@@ -1,18 +1,19 @@
 class_name ClosableMenu extends Control
 
-@export var isOpen: bool:
-  set(newValue):
-    isOpen = newValue
-    visible = newValue
-    if newValue:
-      opened.emit()
-    else:
-      closed.emit()
+signal opened
+signal closed
+signal focusGained
+signal focusLost
+
+@export var canClose:bool = true
+@export var isOpen:bool = false:
+  set(v):
+    isOpen = v
+    visible = v
   get():
     return isOpen
 
-signal closed
-signal opened
+var _savedFocusNode:Control = null
 
 func _enter_tree() -> void:
   visible = isOpen
@@ -22,13 +23,54 @@ func _exit_tree() -> void:
 
 func _ready() -> void:
   visible = isOpen
-  print("ClosableMenu is ready, isOpen: ", isOpen)
-
-func close() -> void:
-  isOpen = false
+  if canClose:
+    set_process_unhandled_input(false)
 
 func open() -> void:
+  visible = true
+  if canClose:
+    UI.FOCUS_STACK.push(self)
   isOpen = true
+  opened.emit()
+
+func close() -> void:
+  if canClose:
+    UI.FOCUS_STACK.pop()
+  isOpen = false
+  closed.emit()
 
 func toggle() -> void:
-  isOpen = !isOpen
+  if isOpen:
+    close()
+  else:
+    open()
+
+func _onFocusGained() -> void:
+  set_process_unhandled_input(true)
+  get_viewport().gui_focus_changed.connect(_onViewportFocusChanged)
+  if _savedFocusNode != null and is_instance_valid(_savedFocusNode):
+    _savedFocusNode.grab_focus()
+  else:
+    _grabInitialFocus()
+  var currentFocus:Control = get_viewport().gui_get_focus_owner()
+  if currentFocus != null and is_ancestor_of(currentFocus):
+    _savedFocusNode = currentFocus
+  focusGained.emit()
+
+func _onFocusLost() -> void:
+  _savedFocusNode = get_viewport().gui_get_focus_owner()
+  if get_viewport().gui_focus_changed.is_connected(_onViewportFocusChanged):
+    get_viewport().gui_focus_changed.disconnect(_onViewportFocusChanged)
+  set_process_unhandled_input(false)
+  focusLost.emit()
+
+func _onViewportFocusChanged(control:Control) -> void:
+  if control == null or is_ancestor_of(control):
+    return
+  if _savedFocusNode != null and is_instance_valid(_savedFocusNode):
+    _savedFocusNode.grab_focus()
+  else:
+    _grabInitialFocus()
+
+func _grabInitialFocus() -> void:
+  pass