extends Camera2D

var last_mouse_position = Vector2.ZERO

func _ready():
	set_process_input(true)

func _input(event):
	if event is InputEventMouseButton:
		if event.button_index == MOUSE_BUTTON_RIGHT and event.pressed:
			last_mouse_position = get_global_mouse_position()
		elif event.button_index == MOUSE_BUTTON_RIGHT and not event.pressed:
			last_mouse_position = Vector2.ZERO
		if event.button_index == MOUSE_BUTTON_WHEEL_DOWN and event.pressed:
			zoom_towards_mouse(Vector2(0.9, 0.9))
		elif event.button_index == MOUSE_BUTTON_WHEEL_UP and event.pressed:
			zoom_towards_mouse(Vector2(1.1, 1.1))
			
	elif event is InputEventPanGesture:
		zoom_towards_mouse(event.delta[1])
		
	elif event is InputEventMouseMotion:
		if last_mouse_position != Vector2.ZERO:
			var mouse_motion = event.relative
			var drag_offset = mouse_motion / zoom
			position -= drag_offset
			last_mouse_position = get_global_mouse_position()

func zoom_towards_mouse(zoom_factor):
	var previous_mouse_position := get_local_mouse_position()
	zoom *= zoom_factor
	var diff = previous_mouse_position - get_local_mouse_position()
	position += diff