Help creating sentery turret AI

// mask of visible objects reported in visList
$AIPlayer::VisObjMask = 
  $TypeMasks::PlayerObjectType |
  $TypeMasks::ProjectileObjectType |
  $TypeMasks::ItemObjectType;

// mask of opaque objects (things that block vision)
$AIPlayer::VisOpaqueMask = 
  $TypeMasks::PlayerObjectType |      // players
  $TypeMasks::TerrainObjectType |     // dirt, but not water
  $TypeMasks::StaticTSObjectType |    // trees and whatnot
  $TypeMasks::InteriorObjectType;     // walls

// mask of visible objects reported in the fastList (subset of $AIPlayer::VisObjMask)
$AIPlayer::VisFastMask = $TypeMasks::ProjectileObjectType;

// all visible objects
$AIPlayer::VisAllMask = $AIPlayer::VisOpaqueMask | $AIPlayer::VisObjMask;

datablock PlayerData(turretBase : defaultPlayer){
   maxInv[CrossbowAmmo] = 50;
   maxInv[Crossbow] = 1;
   
   maxVisDis = 50;
   
   Team = "Players";
};

function turretBase::onAdd(%this, %obj){
   %obj.setRechargeRate(%this.rechargeRate);
   %obj.setRepairRate(0);
   
   %obj.setInventory(Crossbow,1);
   %obj.setInventory(CrossbowAmmo,50);
   %obj.mountImage(CrossbowImage,0);   
   
   
   
   %obj.turretStartup();
}

function AIPlayer::turretStartup(%this) {
   
   echo("Turret-" @ %this @ " is online");
   
   //%this.schedule(2000, "lookForTarget");
}

function AIPlayer::lookForTarget(%this){
   
   if(!(%target = %this.closestTarget())){
      //echo("No Target!");
      %this.fire(false);
      %this.schedule(100, "lookForTarget");
      return;
   }
   //echo(%target);
   %this.aimAt(%target);
   %this.fire(true);
   
   %this.schedule(100, "lookForTarget");
}

function AIPlayer::closestTarget(%this){
   
   initContainerRadiusSearch(%this.getEyePoint(), %this.getDataBlock().maxVisDis, $AIPlayer::VisOpaqueMask);
   
   %closestDistance = %this.getDataBlock().maxVisDis + 1;
   
   %bestTarget = false;   
   
   while( isObject(%obj = containerSearchNext()) )
   {
      if (%obj & $TypeMasks::PlayerObjectType){
         echo(%obj);         
         if(%obj.getDatablock().Team !$= %this.getDataBlock().Team)
         {
            %rad = containerSearchCurrRadiusDist();
            if ( %rad < %closestDistance)
            {
               %closestDistance = %rad;
               
               %bestTarget = %obj;
            }
         }
      }
   }
   
   return %bestTarget;
}