Reverse Direction of Scrolling Panel

Hello guys, haven’t been here in a while.
But I have a simple problem I think.

I have a moving panel of images, and I want to be able to change the direction of the panel with the click of a button. Here’s what I have so far:

var panelSpeed:Number = 1;
var leftDirection:int = -1;
var rightDirection:int = +1;
var panelDirection:*;

stage.addEventListener(Event.ENTER_FRAME,scrollPanel,false,0,true);

scrollLeft.addEventListener(MouseEvent.CLICK,moveLeft);
scrollRight.addEventListener(MouseEvent.CLICK,moveRight);

function scrollPanel (event:Event):void
{
panel.x -= panelSpeed;
}

function moveLeft (event:MouseEvent):void
{
//panelDirection = ???;
}

function moveRight (event:MouseEvent):void
{
//panelDirection = ???;
}

As of now this panel is scrolling to the left, and I would like the option to have it scroll to the right on the click of a button. Right now I’m stuck guys. Thanks a bunch for any guidance.

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