/**
  * @return mixed
  */
 public function postPlayers(PlayerRegistrationRequest $request, GroupRegistration $registration)
 {
     // map the POSTed data to the season data required
     foreach ($request->get('player') as $playerId => $playerData) {
         if (isset($playerData['register']) && $playerData['register'] == 1) {
             $registration->addPlayer($playerId, $playerData['grade'], $playerData['shirtSize']);
         }
     }
     // if they followed a link to get to the registration
     // auto-associate them with this group
     $familiarGroup = Session::getGroupToRegisterWith();
     if ($familiarGroup !== null) {
         $registration->addGroup($familiarGroup);
     }
     // save in session so we can show this info on
     // the summary page
     Session::setSeasonalGroupRegistration($registration);
     // sometimes parents can override the program selection
     if ($registration->requiresProgramSelection()) {
         return redirect('/register/program');
     }
     return redirect('/register/summary');
 }