// Adjusted by http://www.box2d.org/manual.html#_Toc258082976
// http://www.box2dflash.org/docs/2.1a/reference/
// http://blog.sethladd.com/2011/09/box2d-javascript-example-walkthrough.html
// http://code.google.com/p/box2dweb/source/browse/trunk/example.html

// Box2d vars
    var b2AABB = Box2D.Collision.b2AABB;
    var b2Vec2 = Box2D.Common.Math.b2Vec2;
    var b2World = Box2D.Dynamics.b2World;
    //var b2BoxDef = Box2D.Collision.Shapes.b2EdgeChainDef;
    var b2BodyDef = Box2D.Dynamics.b2BodyDef;
    var b2PolygonShape = Box2D.Collision.Shapes.b2PolygonShape;
    var b2FixtureDef = Box2D.Dynamics.b2FixtureDef;
    var b2BodyDef = Box2D.Dynamics.b2BodyDef;
    var b2Body = Box2D.Dynamics.b2Body;
    var b2CircleShape = Box2D.Collision.Shapes.b2CircleShape;
    var b2Shape = Box2D.Collision.Shapes.b2Shape;
    var b2Math = Box2D.Common.Math.b2Math22;
    var b2DebugDraw = Box2D.Dynamics.b2DebugDraw;

function drawWorld(world, context) {
    for (var j = world.m_jointList; j; j = j.m_next) {
        drawJoint(j, context);
    }
    for (var b = world.m_bodyList; b; b = b.m_next) {

        //console.log(b);

        //for (var s = b.GetShapeList(); s != null; s = s.GetNext()) {
        for (var s = b.GetFixtureList(); s != null; s = s.GetNext()) {
            drawShape(s, context);
        }
    }
}
function drawJoint(joint, context) {
    var b1 = joint.m_body1;
    var b2 = joint.m_body2;
    var x1 = b1.m_position;
    var x2 = b2.m_position;
    var p1 = joint.GetAnchor1();
    var p2 = joint.GetAnchor2();
    context.strokeStyle = '#00eeee';
    context.beginPath();
    switch (joint.m_type) {
    case b2Joint.e_distanceJoint:
        context.moveTo(p1.x, p1.y);
        context.lineTo(p2.x, p2.y);
        break;
    case b2Joint.e_pulleyJoint:
        // TODO
        break;
    default:
        if (b1 == world.m_groundBody) {
            context.moveTo(p1.x, p1.y);
            context.lineTo(x2.x, x2.y);
        }
        else if (b2 == world.m_groundBody) {
            context.moveTo(p1.x, p1.y);
            context.lineTo(x1.x, x1.y);
        }
        else {
            context.moveTo(x1.x, x1.y);
            context.lineTo(p1.x, p1.y);
            context.lineTo(x2.x, x2.y);
            context.lineTo(p2.x, p2.y);
        }
        break;
    }
    context.stroke();
}
function drawShape(shape, context) {

    context.strokeStyle = '#000000';
    context.beginPath();

    console.log('type:');
    console.log(shape.GetType()); //0 or 1

    switch (shape.m_type) {
    //switch (shape.GetType()) {
    case b2Shape.e_circleShape:
        {
            return;
            var circle = shape;
            var pos = circle.m_position;
            var r = circle.m_radius;
            var segments = 16.0;
            var theta = 0.0;
            var dtheta = 2.0 * Math.PI / segments;
            // draw circle
            context.moveTo(pos.x + r, pos.y);
            for (var i = 0; i < segments; i++) {
                var d = new b2Vec2(r * Math.cos(theta), r * Math.sin(theta));
                var v = b2Math.AddVV(pos, d);
                context.lineTo(v.x, v.y);
                theta += dtheta;
            }
            context.lineTo(pos.x + r, pos.y);
            // draw radius
            context.moveTo(pos.x, pos.y);
            var ax = circle.m_R.col1;
            var pos2 = new b2Vec2(pos.x + r * ax.x, pos.y + r * ax.y);
            context.lineTo(pos2.x, pos2.y);
        }
        break;
    case b2Shape.e_polyShape:
        {

            var poly = shape;

            //console.log(poly);

            //var tV = b2Math.AddVV(poly.m_position, b2Math.b2MulMV(poly.m_R, poly.m_vertices[0]));
            var tV = b2Math.AddVV(poly.m_position, b2Math.b2MulMV(poly.m_R, poly.GetVertices()[0]));
            /*
            context.moveTo(tV.x, tV.y);
            for (var i = 0; i < poly.m_vertexCount; i++) {
                var v = b2Math.AddVV(poly.m_position, b2Math.b2MulMV(poly.m_R, poly.m_vertices[i]));
                context.lineTo(v.x, v.y);
            }
            context.lineTo(tV.x, tV.y);
            */
        }
        break;
    }
    context.stroke();
}
function createWorld() {
    var worldAABB = new b2AABB();

    //worldAABB.minVertex.Set(-1000, -1000);
    worldAABB.lowerBound.Set(-1000, -1000);
    //worldAABB.maxVertex.Set(1000, 1000);
    worldAABB.upperBound.Set(1000, 1000);
    var gravity = new b2Vec2(0, 300);
    var doSleep = true;
    var world = new b2World(worldAABB, gravity, doSleep);
    return world;
}
function createGround(world) {
    var groundSd = new b2BoxDef();
    groundSd.extents.Set(1000, 50);
    groundSd.restitution = 0.2;
    var groundBd = new b2BodyDef();
    groundBd.AddShape(groundSd);
    groundBd.position.Set(-500, 340);
    return world.CreateBody(groundBd)
}
function createBall(world, x, y) {  //not used
    var ballSd = new b2CircleDef();
    ballSd.density = 1.0;
    ballSd.radius = 20;
    ballSd.restitution = 1.0;
    ballSd.friction = 0;
    var ballBd = new b2BodyDef();
    ballBd.AddShape(ballSd);
    ballBd.position.Set(x,y);
    return world.CreateBody(ballBd);
}
function createBox(world, x, y, width, height, fixed, userData) {
    if (typeof(fixed) == 'undefined') fixed = true;
    //var boxSd = new b2BoxDef();

    //console.log(boxSd);
/*
    if (!fixed) boxSd.density = 1.0;
    boxSd.userData = userData;
    boxSd.extents.Set(width, height);
    */

    /* is kit psl **/

    var bodyDef = new b2BodyDef;

    bodyDef.type = b2Body.b2_dynamicBody;

    var fixDef = new b2FixtureDef;
    fixDef.shape = new b2PolygonShape;
    fixDef.shape.SetAsBox(
          width //half width
       ,  height //half height
    );

    bodyDef.position.x = x;
    bodyDef.position.y = y;
    return world.CreateBody(bodyDef).CreateFixture(fixDef);
    /* end mano */
/*
    var boxBd = new b2BodyDef();
    boxBd.AddShape(boxSd);
    boxBd.position.Set(x,y);
    return world.CreateBody(boxBd)
    */
}