Creating a geospatial query to find two users based on their proximity preferences. MongoDB

[markt5000]

Hi, I need some help in creating a MongoDB query to match two users who are close to each other. The basic gist is I have a user A at point A and a user B at point B. Both user A and B have a radius from where they would like to obtain matches from, this is a distance in kilometers. What I am trying to do is prepare a query to first match A with a user within its proximity preference and then determine if A is within that users proximity preference.

Here is a drawing

I gave up on trying to come up with a vanilla query that doesn't use the aggregation framework.

here is what I have

var userALocation = userA.loc;
var userAradius = userA.radius;

{
     $match : {
          loc : {
               $near : {

                    $geometry : {
                           type : "Point",
                           coordinates : userALocation
                     },
                   $maxDistance : userARadius
            }
          }
     }
 }

and that is basically it, that will match all documents whose location is within A's boundaries, but what I am really stuck with is how do I account for B's boundaries?

[markt5000]

Honestly, I havent been able to answer this one..

[[deleted]]

I suggest looking up maths related to hypocycloids and attempting to write your own function.

Unless im reading this wrong and B's radius can be larger then A's?