Level of "buddy-ism"

I agree!

I don't use most of the stuff included on buddylist modules, like groups (although if these could be defined only by administrators, that could solve the level of buddy-ism.

Right now I haven't had time to figure out how to do this on a module, so I just wrote the code to solve the shortest path between two users urign Dijkstra algorithm. Here it is:

/* Dijstra algorithm */
function spaniards_getbuddypath($startid, $finalid)
{
	// Load vertex (users) map
  $users = array();
  // Users with buddies
  $result = db_query("select distinct uid from buddylist");
  while ($usr = db_fetch_object($result)) {
    $users[$usr->uid] = $usr->uid;
  }
  // Users without buddies but which are buddies of somebody
  $result = db_query("select distinct buddy as uid from buddylist");
  while ($usr = db_fetch_object($result)) {
  	if (!isset($users[$usr->uid]))
  	  $users[$usr->uid] = $usr->uid;
  }
  if (!isset($users[$startid])) return array();
  if (!isset($users[$finalid])) return array();

  $infinity = 999999999; // Make this number bigger than the total of users * highest weight
  $distance = array();
  $userpred = array();
  $paths    = array();

  // Initialize vertex arrays
  foreach($users as $uid) {
    $distance[$uid] = $infinity;
    $userpred[$uid] = 0;
    $paths[$uid]    = array();
  }

  // Load all paths
  $result = db_query("select uid, buddy, 1 as weight from buddylist order by uid, buddy");
  while ($relation = db_fetch_object($result)) {
  	$paths[$relation->uid][$relation->buddy] = $relation->weight;
  }

  // Set starting point
  $distance[$startid] = 0;

  // Process all vertex (users)
  while (count($users) > 0)
  {
    // Calculate the closest user and extract it from the array
    $closestid   = 0;
    $closestdist = $infinity;
    foreach($users as $uid) {
      if ($distance[$uid] <= $closestdist) {
        $closestdist = $distance[$uid];
        $closestid = $uid;
      }
    }
  	$baseid = $users[$closestid];
  	unset($users[$closestid]);

  	if ($baseid == $finalid) break;

    // Process paths for the closest user
    $emanatingpaths = $paths[$baseid];
    foreach ($emanatingpaths as $currentid => $weight) {
      if (in_array($currentid, $users)) {
        if ($distance[$baseid] + $weight < $distance[$currentid]) {
          $distance[$currentid] = $distance[$baseid] + $weight;
          $userpred[$currentid] = $baseid;
        }
      }
    }
  }

  // Read the path backwards, from finalid to startid
  $shortpath = array();
  if ($distance[$finalid] < $infinity) {
    $buddyid = $finalid;
    while ($buddyid > 0) {
      array_unshift($shortpath, $buddyid); // insert new buddy at the beginning
      $buddyid = $userpred[$buddyid];
    }
  }
  return $shortpath;
}

If anybody is interested, feel free to use it or to put it on a module. Or if anybody wants to explain me how to do that, that would be nice.

You can see the result of this code on my webpage, here:
http://www.spaniards.es/node/2420

I'm sorry but only registered users can see it working on their profiles.

Thanks.

The link I posted before is a link to a screenshot. You can see it on Flickr too:
http://www.flickr.com/photos/eneko/423337561/

PS: I bet this code doesn't follow any Drupal coding standars but that's up to you if you want to use it :)

Thanks.