package
{

    import flash.display.Sprite;
    import flash.events.Event;
    import flash.events.TimerEvent;
    import flash.utils.Timer;

    import nape.geom.Vec2;
    import nape.phys.Body;
    import nape.phys.BodyType;
    import nape.phys.Material;
    import nape.shape.Polygon;
    import nape.space.Broadphase;
    import nape.space.Space;
    import nape.util.ShapeDebug;

    [SWF(width=800, height=600, backgroundColor=0x000000, frameRate=30)]
    /**
     *
     */
    public class Nape2KinematicBody extends Sprite
    {
        //
        static public const APP_WIDTH:int = 800;
        static public const APP_HEIGHT:int = 600;

        //
        private var _space:Space;
        private var _timeStep:Number = 1/30.0;
        private var _velocityIterations:int = 10;
        private var _positionIterations:int = 10;

        private var _debug:ShapeDebug;
        private var _kinematicBody:Body;
        private var _anotherKinematicBody:Body = new Body(BodyType.KINEMATIC);


        public function Nape2KinematicBody()
        {
            if (stage) init();
            else addEventListener(Event.ADDED_TO_STAGE, init);
        }

        /**
         */
        private function init(event:Event = null):void
        {
            removeEventListener(Event.ADDED_TO_STAGE, init);

            _space = new Space(new Vec2(0, 400), Broadphase.SWEEP_AND_PRUNE);
            createBodies();
            initDebugDraw();

            addEventListener(Event.ENTER_FRAME, enterFrameHandler);
        }

        /**
         */
        private function createBodies():void
        {
            _kinematicBody = new Body(BodyType.KINEMATIC);
            _kinematicBody.velocity.setxy(0, 200);

            var kinematicShape:Polygon = new Polygon(Polygon.box(300, 50), new Material());
            _kinematicBody.shapes.add(kinematicShape);

            var dynamicBoxShape:Polygon = new Polygon(Polygon.box(50, 50), new Material());
            var dynamicBody:Body = new Body(BodyType.DYNAMIC);
            dynamicBody.shapes.add(dynamicBoxShape);

            _anotherKinematicBody.shapes.add(new Polygon(Polygon.box(600, 50), new Material()));

            //
            _kinematicBody.position.setxy(APP_WIDTH/2, 300);
            _anotherKinematicBody.position.setxy(APP_WIDTH/2, 300);
            dynamicBody.position.setxy(APP_WIDTH/2, 250);

            //
            _kinematicBody.space = _space;
            _anotherKinematicBody.space = _space;
            dynamicBody.space = _space;

            //
            var timer:Timer = new Timer(6500, 0);
            timer.addEventListener(TimerEvent.TIMER, moveAnotherPlatform);
            timer.start();
        }

        private var _isMove:Boolean = false;

        /**
         */
        private function moveAnotherPlatform(event:TimerEvent):void
        {
            _isMove = !_isMove;

            if (_isMove) _anotherKinematicBody.velocity.setxy(0, 20);
            else _anotherKinematicBody.velocity.setxy(0, 0);
        }

        /**
         */
        private function initDebugDraw():void
        {
            _debug = new ShapeDebug(APP_WIDTH, APP_HEIGHT, 0x000000);
            addChild(_debug.display);
        }


        /**
         */
        private function enterFrameHandler(event:Event):void
        {
            _space.step(_timeStep, _velocityIterations, _positionIterations);

            _debug.clear();
            _debug.draw(_space);
            _debug.flush();

            updateKinematicPosition();
        }

        /**
         */
        private function updateKinematicPosition():void
        {
            if (_kinematicBody.position.y > 600)
            {
                _kinematicBody.velocity.y = -_kinematicBody.velocity.y;
                _anotherKinematicBody.velocity.y = -_anotherKinematicBody.velocity.y;
            }
            else if (_kinematicBody.position.y < 50)
            {
                _kinematicBody.velocity.y = -_kinematicBody.velocity.y;
                _anotherKinematicBody.velocity.y = -_anotherKinematicBody.velocity.y;
            }
        }
    }
}