package{
	
	import flash.display.Sprite;
	import flash.display.MovieClip;
	import flash.events.Event;
	// Classes used in this example
	import Box2D.Dynamics.*;
	import Box2D.Collision.*;
	import Box2D.Collision.Shapes.*;
	import Box2D.Common.Math.*;
	
	public class HelloBox2D extends Sprite{
		
		
		public var m_world:b2World;
		public var m_iterations:int = 10;
		public var m_timeStep:Number = 1/30;
		
		public function HelloBox2D(){
			
			// STAGE PROPERTIES
			//stage.scaleMode = StageScaleMode.NO_SCALE;
			//stage.align = StageAlign.TOP_LEFT;
			//stage.quality = "low";
			
			// Add event for main loop
			addEventListener(Event.ENTER_FRAME, Update, false, 0, true);
			
			
			
			// Creat world AABB
			var worldAABB:b2AABB = new b2AABB();
			//worldAABB.minVertex.Set(-1000.0, -1000.0);
			//worldAABB.maxVertex.Set(1000.0, 1000.0);
			
			// try to make this work with stage variables
			worldAABB.minVertex.Set (0, 0);
			worldAABB.maxVertex.Set (stage.stageWidth, stage.stageHeight);
			
			// Define the gravity vector
			var gravity:b2Vec2 = new b2Vec2(0.0, 300.0);
			
			// Allow bodies to sleep
			var doSleep:Boolean = true;
			
			// Construct a world object
			m_world = new b2World(worldAABB, gravity, doSleep);
			
			
			
			// Vars used to create bodies
			var bodyDef:b2BodyDef;
			var boxDef:b2BoxDef;
			var circleDef:b2CircleDef;
			
			
			
			// Add ground body
			bodyDef = new b2BodyDef();
			boxDef = new b2BoxDef();
			bodyDef.userData = PhysGround;
						
			boxDef.extents.Set(bodyDef.userData.width / 2, bodyDef.userData.height / 2);
			boxDef.friction = 0.3;

			bodyDef.position.Set(bodyDef.userData.x, bodyDef.userData.y);
			bodyDef.AddShape(boxDef);
			
			
			addChild(bodyDef.userData);
			m_world.CreateBody(bodyDef);
			
			
			
			/// LETS ADD A SECOND GROUND BODY FOR TESTING PURPOSES
			
			// Add ground body
			bodyDef = new b2BodyDef();
			boxDef = new b2BoxDef();
			bodyDef.userData = PhysGround2;
			
			boxDef.extents.Set(bodyDef.userData.width / 2, bodyDef.userData.height / 2);
			boxDef.friction = 0.3;

			bodyDef.position.Set(bodyDef.userData.x, bodyDef.userData.y);
			bodyDef.AddShape(boxDef);
			
			addChild(bodyDef.userData);
			m_world.CreateBody(bodyDef);
			
			
			// Add some objects
			for (var i:int = 1; i < 20; i++){
				bodyDef = new b2BodyDef();
				// Box

				// Circle
				circleDef = new b2CircleDef();
				circleDef.radius = Math.random() * 15;
				circleDef.density = 1.0;
				circleDef.friction = 0.5;
				circleDef.restitution = 0.2
				
				
				bodyDef.AddShape(circleDef);
				bodyDef.userData = new PhysCircle();
				bodyDef.userData.width = circleDef.radius * 2; 
				bodyDef.userData.height = circleDef.radius * 2; 
				bodyDef.position.x = Math.random() * stage.stageWidth;
				bodyDef.position.y = Math.random() * stage.stageHeight * 2/3;
				
				
				m_world.CreateBody(bodyDef);
				addChild(bodyDef.userData);
			}
			
		}
		
		public function Update(e:Event):void{
			
			m_world.Step(m_timeStep, m_iterations);
			
			// Go through body list and update sprite positions/rotations
			for (var bb:b2Body = m_world.m_bodyList; bb; bb = bb.m_next){
				if (bb.m_userData is Sprite){
					bb.m_userData.x = bb.m_position.x;
					bb.m_userData.y = bb.m_position.y;
					bb.m_userData.rotation = bb.m_rotation * (180/Math.PI);
				}
			}
			
		}

		
	}

}