package {
	import flash.display.Sprite;
	import flash.events.Event;
	import flash.events.MouseEvent;
	import Box2D.Dynamics.*;
	import Box2D.Collision.*;
	import Box2D.Collision.Shapes.*;
	import Box2D.Common.Math.*;
	public class HelloWorld extends Sprite {
		public var m_world:b2World;
		public var m_iterations:int=10;
		public var m_timeStep:Number=1.0/30.0;
		public var the_arrow:arrow=new arrow();
		public var the_arrow_angle:Number;
		public var my_canvas:Sprite = new Sprite();
		public var deg_to_rad:Number=0.0174532925;
		public var rad_to_deg:Number=57.2957795;
		public var charging:Boolean=false;
		public var power:int=0;
		public var impulse:Boolean=false;
		public function HelloWorld() {
			addChild(the_arrow);
			addChild(my_canvas);
			var worldAABB:b2AABB = new b2AABB();
			worldAABB.lowerBound.Set(-100.0, -100.0);
			worldAABB.upperBound.Set(100.0, 100.0);
			var gravity:b2Vec2=new b2Vec2(0.0,10.0);
			var doSleep:Boolean=true;
			m_world=new b2World(worldAABB,gravity,doSleep);
			// debug draw
			var m_sprite:Sprite;
			m_sprite = new Sprite();
			addChild(m_sprite);
			var dbgDraw:b2DebugDraw = new b2DebugDraw();
			var dbgSprite:Sprite = new Sprite();
			m_sprite.addChild(dbgSprite);
			dbgDraw.m_sprite=m_sprite;
			dbgDraw.m_drawScale=30;
			dbgDraw.m_alpha=1;
			dbgDraw.m_fillAlpha=0.5;
			dbgDraw.m_lineThickness=1;
			dbgDraw.m_drawFlags=b2DebugDraw.e_shapeBit;
			m_world.SetDebugDraw(dbgDraw);
			// end debug draw
			// Vars used to create bodies
			var body:b2Body;
			var bodyDef:b2BodyDef;
			var boxDef:b2PolygonDef;
			var circleDef:b2CircleDef;
			// Add ground body
			bodyDef = new b2BodyDef();
			bodyDef.position.Set(10, 14);
			boxDef = new b2PolygonDef();
			boxDef.SetAsBox(30, 1);
			boxDef.friction=0.3;
			boxDef.density=0;
			body=m_world.CreateBody(bodyDef);
			body.CreateShape(boxDef);
			body.SetMassFromShapes();
			//
			bodyDef = new b2BodyDef();
			bodyDef.position.Set(5, 5);
			circleDef = new b2CircleDef();
			circleDef.radius=0.5;
			circleDef.density=1.0;
			circleDef.friction=0.5;
			circleDef.restitution=0.2;
			bodyDef.userData = new Sprite();
			bodyDef.userData.name="Player";
			body=m_world.CreateBody(bodyDef);
			body.CreateShape(circleDef);
			body.SetMassFromShapes();
			//
			addEventListener(Event.ENTER_FRAME, Update, false, 0, true);
			stage.addEventListener(MouseEvent.MOUSE_UP, shoot);
			stage.addEventListener(MouseEvent.MOUSE_DOWN,charge);
 
		}
		public function Update(e:Event):void {
			m_world.Step(m_timeStep, m_iterations);
			for (var bb:b2Body = m_world.m_bodyList; bb; bb = bb.m_next) {
				if (bb.GetUserData()!=null) {
					the_arrow.x=bb.m_userData.x=bb.GetPosition().x*30;
					the_arrow.y=bb.m_userData.y=bb.GetPosition().y*30;
					var dist_x=the_arrow.x-mouseX;
					var dist_y=the_arrow.y-mouseY;
					the_arrow_angle=Math.atan2(- dist_y,- dist_x);
					the_arrow.rotation=the_arrow_angle*rad_to_deg;
					if (charging) {
						power++;
						if (power>=120) {
							power-=120;
						}
						my_canvas.graphics.clear();
						my_canvas.graphics.lineStyle(3,0x000000,0.5);
						draw_arc(my_canvas,the_arrow.x=bb.m_userData.x=bb.GetPosition().x*30,the_arrow.y=bb.m_userData.y=bb.GetPosition().y*30,20,270,270+power*3,1);
					}
					if (impulse) {
						bb.ApplyImpulse(new b2Vec2(Math.cos(the_arrow_angle)*power/4, Math.sin(the_arrow_angle)*power/4),bb.GetWorldCenter());
						impulse=false;
						power=0;
					}
				}
			}
		}
		public function charge(e:MouseEvent):void {
			charging=true;
		}
		public function shoot(e:MouseEvent):void {
			charging=false;
			my_canvas.graphics.clear();
			impulse=true;
		}
		public function draw_arc(movieclip,center_x,center_y,radius,angle_from,angle_to,precision):void {
			var angle_diff=angle_to-angle_from;
			var steps=Math.round(angle_diff*precision);
			var angle=angle_from;
			var px=center_x+radius*Math.cos(angle*deg_to_rad);
			var py=center_y+radius*Math.sin(angle*deg_to_rad);
			movieclip.graphics.moveTo(px,py);
			for (var i:int=1; i<=steps; i++) {
				angle=angle_from+angle_diff/steps*i;
				movieclip.graphics.lineTo(center_x+radius*Math.cos(angle*deg_to_rad),center_y+radius*Math.sin(angle*deg_to_rad));
			}
		}
 
 
	}
}