first iteration with authorative movement

scripts/state_machine.gd

@@ -0,0 +1,33 @@
+extends Node
+
+@export var starting_state: State
+
+var current_state: State
+
+func init(subject: Node) -> void:
+	for state in get_children():
+		state.subject = subject
+
+	_change_state(starting_state)
+
+func _change_state(new_state: State) -> void:
+	if current_state:
+		current_state.exit()
+
+	current_state = new_state
+	current_state.enter()
+
+func _physics_process(delta: float) -> void:
+	var new_state = current_state.process_physics(delta)
+	if new_state:
+		_change_state(new_state)
+
+func _unhandled_input(event: InputEvent) -> void:
+	var new_state = current_state.process_input(event)
+	if new_state:
+		_change_state(new_state)
+
+func _process(delta: float) -> void:
+	var new_state = current_state.process_frame(delta)
+	if new_state:
+		_change_state(new_state)