package {

import com.actionsnippet.qbox.*;
import Box2D.Collision.*;
import Box2D.Collision.Shapes.*;
import Box2D.Dynamics.Contacts.*;
import Box2D.Dynamics.*;
import Box2D.Common.Math.*;
import Box2D.Common.*;

public class QuickContactFilter extends b2ContactFilter
{

    private var indices:Array = [];
    private var callbacks:Array = [];
	
    public function addGroupIndexCallback(func:Function, index:int):void{
		callbacks.push(func);
		indices.push(index);
	}
	
	override public function ShouldCollide(shape1:b2Shape, shape2:b2Shape):Boolean{
		var filter1:b2FilterData = shape1.GetFilterData();
		var filter2:b2FilterData = shape2.GetFilterData();
		
		// only difference between default Box2D behavior
		for (var i:int = 0; i<indices.length; i++){
			var index:int = indices[i];
			if (filter1.groupIndex == index && filter2.groupIndex == index){
				callbacks[i](shape1, shape2);
			}
		}
		// -- 
		
		if (filter1.groupIndex == filter2.groupIndex && filter1.groupIndex != 0)
		{
			return filter1.groupIndex > 0;
		}
		
		var collide:Boolean = (filter1.maskBits & filter2.categoryBits) != 0 && (filter1.categoryBits & filter2.maskBits) != 0;
		return collide;
	}
	
}
}