class_name StateMachine extends Node

export (NodePath) var starting_state
export var debug_state_machine: bool = false

var current_state: State
var state_modifiers: Array

# Initialize the state machine by giving each child state a reference to the
# parent object it belongs to and enter the default starting_state.
func init() -> void:
	for child in get_children():
		if child is State:
			if debug_state_machine:
				print("Initializing State Node: ", child.name)
			child.modifier_stack_ref = state_modifiers
			if debug_state_machine:
				child.debug_state = true

	# Initialize to the default state
	change_state(get_node(starting_state))

# Change to the new state by first calling any exit logic on the current state.
func change_state(new_state: State) -> void:
	if current_state:
		current_state.exit()

	current_state = new_state
	current_state.enter()
	if(state_modifiers.size() > 0 and debug_state_machine):
		print("Active Modifiers:")
		for mods in state_modifiers:
			print(mods.name)
	
# Pass through functions for the Player to call,
# handling state changes as needed.
func process_physics(delta: float) -> void:
	var new_state = current_state.process_physics(delta)
	if new_state:
		change_state(new_state)

func process_input(event: InputEvent) -> void:
	var new_state = current_state.process_input(event)
	if new_state:
		change_state(new_state)

func process_frame(delta: float) -> void:
	var new_state = current_state.process_frame(delta)
	if new_state:
		change_state(new_state)