extends Node


signal swipe_left
signal swipe_right
signal swipe_up
signal swipe_down

var swipe_start: Vector2
var swipe_done = false

const MAX_SWIPE_DISTANCE = 80


func _unhandled_input(event):
	if event is InputEventScreenTouch:
		if event.pressed:
			swipe_done = false
			swipe_start = event.get_position()
		elif not swipe_done:
			_interpret_swipe(event.get_position())
	elif event is InputEventScreenDrag:
		if not swipe_done:
			_interpret_swipe(event.position)


func _interpret_swipe(swipe_end: Vector2):
	var diff = swipe_end - swipe_start
	
	if diff.length_squared() > MAX_SWIPE_DISTANCE * MAX_SWIPE_DISTANCE:
		var normalized = diff.normalized()
		
		if normalized.x > 0.5:
			emit_signal("swipe_right")
		elif normalized.x < -0.5:
			emit_signal("swipe_left")
		elif normalized.y > 0.5:
			emit_signal("swipe_down")
		else:
			emit_signal("swipe_up")
		
		swipe_done = true