ArrowKeyMovement

package  libTF.interfaces
{
    import flash.display.Shape;
    import flash.events.EventDispatcher;
    import flash.events.Event;
    import flash.events.IEventDispatcher;
    import flash.geom.Rectangle;
    import flash.ui.Keyboard;

    public class ArrowKeyMovement
    {
        public var friction:Number;
        public var speed:int;
        public var x:int, y:int;
        public var xVel:Number, yVel:Number;
        public var bounds:Rectangle;
        private var keyBind:int;

        public function ArrowKeyMovement(spd:int, bnd:Rectangle = null, frict:Number = 1, arrows:Boolean = true, wasd:Boolean = false)
        {
            speed = spd;
            bounds = bnd;
            friction = frict;
            x = y = 0;
            xVel = yVel = 0;
            keyBind = int(arrows) + (int(wasd) << 1);
            keyBind = (!keyBind)?1:keyBind;
            (new Shape()).addEventListener(Event.ENTER_FRAME, move);
        }

        public function useArrows():void {keyBind = 1;}
        public function useWASD():void {keyBind = 2;}
        public function useBoth():void {keyBind = 3;}

        private function move(e:Event):void
        {
            xVel *= (1 - friction);
            yVel *= (1 - friction);
            if (keyBind == 1) { handleArrows(); }
            else if (keyBind == 2) { handleWASD(); }
            else if (keyBind == 3) { handleBoth(); }
            x += xVel;
            y += yVel;
            if (bounds)
            {
                if (x < bounds.x) { x = bounds.x; xVel = 0; }
                else if (x > bounds.x + bounds.width) { x = bounds.x + bounds.width;  xVel = 0; }
                if (y < bounds.y) { y = bounds.y; yVel = 0; }
                else if (y > bounds.y + bounds.height) { y = bounds.y + bounds.height; yVel = 0; }
            }
        }

        private function handleWASD():void
        {
            if (KeyManager.isPressed(65)) { xVel -= speed; }
            if (KeyManager.isPressed(87)) { yVel -= speed; }
            if (KeyManager.isPressed(68)) { xVel += speed; }
            if (KeyManager.isPressed(83)) { yVel += speed; }
        }

        private function handleArrows():void
        {
            if (KeyManager.isPressed(37)) { xVel -= speed; }
            if (KeyManager.isPressed(38)) { yVel -= speed; }
            if (KeyManager.isPressed(39)) { xVel += speed; }
            if (KeyManager.isPressed(40)) { yVel += speed; }
        }
        private function handleBoth():void
        {
            if (KeyManager.isPressed(37) || KeyManager.isPressed(65)) { xVel -= speed; }
            if (KeyManager.isPressed(38) || KeyManager.isPressed(87)) { yVel -= speed; }
            if (KeyManager.isPressed(39) || KeyManager.isPressed(68)) { xVel += speed; }
            if (KeyManager.isPressed(40) || KeyManager.isPressed(83)) { yVel += speed; }
        }

    }

}