package be.devine.ogp.view
{
	import Box2D.Collision.Shapes.b2CircleShape;
	import Box2D.Collision.Shapes.b2PolygonShape;
	import Box2D.Collision.b2AABB;
	import Box2D.Common.Math.b2Vec2;
	import Box2D.Dynamics.Joints.b2Joint;
	import Box2D.Dynamics.Joints.b2PrismaticJoint;
	import Box2D.Dynamics.Joints.b2PrismaticJointDef;
	import Box2D.Dynamics.b2Body;
	import Box2D.Dynamics.b2BodyDef;
	import Box2D.Dynamics.b2DebugDraw;
	import Box2D.Dynamics.b2FixtureDef;
	import Box2D.Dynamics.b2World;

	import flash.display.Sprite;
	import flash.events.Event;

	public class GameView extends Sprite
	{
		private var _pixelsToMeter:uint = 30;
		private var _groundHeight:uint = 60;
		private var _world:b2World;
		private var _gravity:b2Vec2;
		private var _doSleep:Boolean = true;
		private var _step:Number = 1/30;
		private var _velocityIterations:uint = 4;
		private var _positionIterations:uint = 4;


		private var groundBody:b2Body
		public function GameView()
		{
			this.addEventListener(Event.ADDED_TO_STAGE,addedToStageHandler);
		}
		private function addedToStageHandler(event:Event):void
		{
			_gravity = new b2Vec2(0.0,10.0);
			_world = new b2World(_gravity,_doSleep);

			createGround();
			createObject();
			createDebugDraw();

			this.addEventListener(Event.ENTER_FRAME,onEnterFrameHandler);
		}
		private var box:b2Body;
		private var the_prism_joint:b2PrismaticJointDef = new b2PrismaticJointDef()
		private var prismaticJointDef:b2PrismaticJointDef;
		private function createObject():void
		{
			makeDynBox();
			var worldAxis:b2Vec2 = new b2Vec2(1.0, 0.0);

			prismaticJointDef = new b2PrismaticJointDef();
			prismaticJointDef.Initialize(body, groundBody, body.GetWorldCenter(), worldAxis);
			prismaticJointDef.lowerTranslation = -2.5;
			prismaticJointDef.upperTranslation = 2.5;
			prismaticJointDef.enableLimit = true;
			prismaticJointDef.maxMotorForce = 10.0;
			prismaticJointDef.motorSpeed = -1.0;
			prismaticJointDef.enableMotor = true;

			_world.CreateJoint(prismaticJointDef);

		}
		private var body:b2Body;
		private function makeDynBox():void
		{
			var bodyDef:b2BodyDef = new b2BodyDef();
			bodyDef.type = b2Body.b2_dynamicBody;
			bodyDef.position.Set(2,1.3);
			body = _world.CreateBody(bodyDef);
			var dynamicBox:b2PolygonShape = new b2PolygonShape();
			dynamicBox.SetAsBox(1,1);
			var fixtureDef:b2FixtureDef = new b2FixtureDef();
			fixtureDef.shape = dynamicBox;
			fixtureDef.density = 1;
			fixtureDef.friction = 0.3;
			body.CreateFixture(fixtureDef);
		}
		private function createGround():void
		{

			var groundBodyDef:b2BodyDef = new b2BodyDef();
			groundBodyDef.position.Set((stage.stageWidth / 2) / _pixelsToMeter, stage.stageHeight / _pixelsToMeter - 20 / _pixelsToMeter);

			groundBody = _world.CreateBody(groundBodyDef);

			var groundBox:b2PolygonShape = new b2PolygonShape();
			groundBox.SetAsBox((stage.stageWidth / 2) / _pixelsToMeter, 20 / _pixelsToMeter);

			var groundFixtureDef:b2FixtureDef = new b2FixtureDef();
			groundFixtureDef.shape = groundBox;
			groundFixtureDef.density = 1;
			groundFixtureDef.friction = 1;
			groundBody.CreateFixture(groundFixtureDef);
		}
		private function createDebugDraw():void{

			var sprite:Sprite = new Sprite();
			this.addChild(sprite);

			var debugDraw:b2DebugDraw = new b2DebugDraw();
			debugDraw.SetSprite(sprite);
			debugDraw.SetAlpha(0.6);
			debugDraw.SetLineThickness(1);
			debugDraw.SetDrawScale(_pixelsToMeter);
			debugDraw.SetFillAlpha(0.6);
			debugDraw.SetFlags(b2DebugDraw.e_shapeBit | b2DebugDraw.e_jointBit);
			_world.SetDebugDraw(debugDraw);
		}
		private function onEnterFrameHandler(event:Event):void
		{
			_world.Step(_step,_velocityIterations,_positionIterations);
			_world.ClearForces();
			_world.DrawDebugData();
			if(!body.IsAwake())
			{
				prismaticJointDef.motorSpeed = 1;
				prismaticJointDef.maxMotorForce = -10;
				body.ApplyTorque(1);
			}
		}
	}
}