extends ScrollContainer
class_name TouchVerticalContainer

const POINTER_VELOCITY_DECAYING_FACTOR: float = 2.5

var is_pointer_dragging		:= false
var pointer_drag_velocity	:= 0.0
var exclude_controls		:= []


func _ready():
	
	for it in get_node("controls").get_children():
		it = it as Control
		if exclude_controls.has(it.name):
			continue
		
		var sensor = PointerInputSensor.new()
		it.add_child(sensor)
		
		sensor.name = "sensor"
		sensor.anchor_right = 1.0
		sensor.anchor_bottom = 1.0
		
		sensor.connect("on_press", self, "pointer_input_on_press_handler")
		sensor.connect("on_drag", self, "pointer_input_on_drag_handler")
		sensor.connect("on_end_drag", self, "pointer_input_on_end_drag_handler")
		sensor.connect("on_click", self, "pointer_input_on_click_handler")
		
		it.connect("focus_entered", sensor, "set_visible", [false])
		it.connect("focus_exited", sensor, "set_visible", [true])


func _process(delta: float):
	# Apply drag movement inertia.
	if is_pointer_dragging == false && abs(pointer_drag_velocity) > 0.5:
		pointer_drag_velocity *= clamp((1.0 - POINTER_VELOCITY_DECAYING_FACTOR * delta), 0.0, 1.0)
		self.scroll_vertical -= pointer_drag_velocity * delta


func pointer_input_on_press_handler(pointer: PointerInputSensor.PointerInputData):
	is_pointer_dragging = true
	grab_focus()


func pointer_input_on_drag_handler(pointer: PointerInputSensor.PointerInputData):
	is_pointer_dragging = true
	pointer_drag_velocity = pointer.velocity.y
	self.scroll_vertical -= pointer.relative_position.y


func pointer_input_on_end_drag_handler(pointer: PointerInputSensor.PointerInputData):
	is_pointer_dragging = false


func pointer_input_on_click_handler(pointer: PointerInputSensor.PointerInputData):
	pointer.target.get_parent().grab_focus()