/*
* Copyright (c) 2006-2007 Erin Catto http:
*
* This software is provided 'as-is', without any express or implied
* warranty.  In no event will the authors be held liable for any damages
* arising from the use of this software.
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked, and must not be
* misrepresented the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/






/**
 * @class b2CircleShape
 * @constructor
 */
var b2CircleShape = function (def, body, localCenter) {
    // initialize instance variables for references
	this.m_R = new b2Mat22();
	this.m_position = new b2Vec2();
	//

	// The constructor for b2Shape
	this.m_userData = def.userData;

	this.m_friction = def.friction;
	this.m_restitution = def.restitution;
	this.m_body = body;

	this.m_proxyId = b2Pair.b2_nullProxy;

	this.m_maxRadius = 0.0;

	this.m_categoryBits = def.categoryBits;
	this.m_maskBits = def.maskBits;
	this.m_groupIndex = def.groupIndex;
	//

	// initialize instance variables for references
	this.m_localPosition = new b2Vec2();
	//

	//super(def, body);

	//b2Settings.b2Assert(def.type == b2Shape.e_circleShape);
	var circle = def;

	//this.m_localPosition = def.localPosition - localCenter;
	this.m_localPosition.Set(def.localPosition.x - localCenter.x, def.localPosition.y - localCenter.y);
	this.m_type = b2Shape.e_circleShape;
	this.m_radius = circle.radius;

	this.m_R.SetM(this.m_body.m_R);
	//b2Vec2 r = b2Mul(this.m_body->this.m_R, this.m_localPosition);
	var rX = this.m_R.col1.x * this.m_localPosition.x + this.m_R.col2.x * this.m_localPosition.y;
	var rY = this.m_R.col1.y * this.m_localPosition.x + this.m_R.col2.y * this.m_localPosition.y;
	//this.m_position = this.m_body->this.m_position + r;
	this.m_position.x = this.m_body.m_position.x + rX;
	this.m_position.y = this.m_body.m_position.y + rY;
	//this.m_maxRadius = r.Length() + this.m_radius;
	this.m_maxRadius = Math.sqrt(rX*rX+rY*rY) + this.m_radius;

	var aabb = new b2AABB();
	aabb.minVertex.Set(this.m_position.x - this.m_radius, this.m_position.y - this.m_radius);
	aabb.maxVertex.Set(this.m_position.x + this.m_radius, this.m_position.y + this.m_radius);

	var broadPhase = this.m_body.m_world.m_broadPhase;
	if (broadPhase.InRange(aabb))
	{
		this.m_proxyId = broadPhase.CreateProxy(aabb, this);
	}
	else
	{
		this.m_proxyId = b2Pair.b2_nullProxy;
	}

	if (this.m_proxyId == b2Pair.b2_nullProxy)
	{
		this.m_body.Freeze();
	}
};
Object.extend(b2CircleShape.prototype, b2Shape.prototype);
Object.extend(b2CircleShape.prototype, 
{
	TestPoint: function(p){
		//var d = b2Math.SubtractVV(p, this.m_position);
		var d = new b2Vec2();
		d.SetV(p);
		d.Subtract(this.m_position);
		return b2Math.b2Dot(d, d) <= this.m_radius * this.m_radius;
	},

	//--------------- Internals Below -------------------

	Synchronize: function(position1, R1, position2, R2){
		this.m_R.SetM(R2);
		//this.m_position = position2 + b2Mul(R2, this.m_localPosition);
		this.m_position.x = (R2.col1.x * this.m_localPosition.x + R2.col2.x * this.m_localPosition.y) + position2.x;
		this.m_position.y = (R2.col1.y * this.m_localPosition.x + R2.col2.y * this.m_localPosition.y) + position2.y;

		if (this.m_proxyId == b2Pair.b2_nullProxy)
		{
			return;
		}

		// Compute an AABB that covers the swept shape (may miss some rotation effect).
		//b2Vec2 p1 = position1 + b2Mul(R1, this.m_localPosition);
		var p1X = position1.x + (R1.col1.x * this.m_localPosition.x + R1.col2.x * this.m_localPosition.y);
		var p1Y = position1.y + (R1.col1.y * this.m_localPosition.x + R1.col2.y * this.m_localPosition.y);
		//b2Vec2 lower = b2Min(p1, this.m_position);
		var lowerX = Math.min(p1X, this.m_position.x);
		var lowerY = Math.min(p1Y, this.m_position.y);
		//b2Vec2 upper = b2Max(p1, this.m_position);
		var upperX = Math.max(p1X, this.m_position.x);
		var upperY = Math.max(p1Y, this.m_position.y);

		var aabb = new b2AABB();
		aabb.minVertex.Set(lowerX - this.m_radius, lowerY - this.m_radius);
		aabb.maxVertex.Set(upperX + this.m_radius, upperY + this.m_radius);

		var broadPhase = this.m_body.m_world.m_broadPhase;
		if (broadPhase.InRange(aabb))
		{
			broadPhase.MoveProxy(this.m_proxyId, aabb);
		}
		else
		{
			this.m_body.Freeze();
		}
	},

	QuickSync: function(position, R){
		this.m_R.SetM(R);
		//this.m_position = position + b2Mul(R, this.m_localPosition);
		this.m_position.x = (R.col1.x * this.m_localPosition.x + R.col2.x * this.m_localPosition.y) + position.x;
		this.m_position.y = (R.col1.y * this.m_localPosition.x + R.col2.y * this.m_localPosition.y) + position.y;
	},


	ResetProxy: function(broadPhase)
	{
		if (this.m_proxyId == b2Pair.b2_nullProxy)
		{
			return;
		}

		var proxy = broadPhase.GetProxy(this.m_proxyId);

		broadPhase.DestroyProxy(this.m_proxyId);
		proxy = null;

		var aabb = new b2AABB();
		aabb.minVertex.Set(this.m_position.x - this.m_radius, this.m_position.y - this.m_radius);
		aabb.maxVertex.Set(this.m_position.x + this.m_radius, this.m_position.y + this.m_radius);

		if (broadPhase.InRange(aabb))
		{
			this.m_proxyId = broadPhase.CreateProxy(aabb, this);
		}
		else
		{
			this.m_proxyId = b2Pair.b2_nullProxy;
		}

		if (this.m_proxyId == b2Pair.b2_nullProxy)
		{
			this.m_body.Freeze();
		}
	},


	Support: function(dX, dY, out)
	{
		//b2Vec2 u = d;
		//u.Normalize();
		var len = Math.sqrt(dX*dX + dY*dY);
		dX /= len;
		dY /= len;
		//return this.m_position + this.m_radius * u;
		out.Set(	this.m_position.x + this.m_radius*dX,
					this.m_position.y + this.m_radius*dY);
	},


	// Local position in parent body
	m_localPosition: new b2Vec2(),
	m_radius: null});