extends Control

var current_scene = null
var loader = null
var wait_frames = 1
var time_max = 100 # msec

func _ready():
	print("[global#_ready] get root scene")
	var root = get_tree().get_root()
	current_scene = root.get_child(root.get_child_count() - 1)
	if current_scene.name != "Main":
		get_node("/root/Loading").hide()

func goto_scene(path):
	print("[global#goto_scene]")
	loader = ResourceLoader.load_interactive(path)
	if loader == null:
		print("Error loading ....")
		return
	
	set_process(true)
	current_scene.queue_free()
	wait_frames = 1
	Loading.get_node("ColorRect/CenterContainer/VBoxContainer/ProgressBar").set_max(loader.get_stage_count())


func _process(_delta):
	print("[global#_process]")
	if loader == null:
		set_process(false)
		return
	
	if wait_frames > 0:
		wait_frames -= 1
	
	var tick = OS.get_ticks_msec()
	
	# Use "time_max" to control for how long we block this thread
	while OS.get_ticks_msec() < tick + time_max:
		var err = loader.poll()
		
		if err == ERR_FILE_EOF: # Finished loading.
			var resource = loader.get_resource()
			loader = null
			set_new_scene(resource)
			get_node("/root/Loading").hide()
			break
		elif err == OK:
			update_progress()
		else:
			print("[global#_process] Error loading")
			loader = null
			break

func update_progress():
	print("[global#update_progress]")
	Loading.visible = true
	Loading.get_node("ColorRect/CenterContainer/VBoxContainer/ProgressBar").set_value(loader.get_stage())

func set_new_scene(scene_resource):
	print("[global#set_new_scene]")
	current_scene = scene_resource.instance()
	get_node("/root").add_child(current_scene)