original_string: public static function login_user($chatid, $groupid = 0) {
          global $DB;
  
          $params = self::validate_parameters(self::login_user_parameters(),
                                              array(
                                                  'chatid' => $chatid,
                                                  'groupid' => $groupid
                                              ));
          $warnings = array();
  
          // Request and permission validation.
          $chat = $DB->get_record('chat', array('id' => $params['chatid']), '*', MUST_EXIST);
          list($course, $cm) = get_course_and_cm_from_instance($chat, 'chat');
  
          $context = context_module::instance($cm->id);
          self::validate_context($context);
  
          require_capability('mod/chat:chat', $context);
  
          if (!empty($params['groupid'])) {
              $groupid = $params['groupid'];
              // Determine is the group is visible to user.
              if (!groups_group_visible($groupid, $course, $cm)) {
                  throw new moodle_exception('notingroup');
              }
          } else {
              // Check to see if groups are being used here.
              if ($groupmode = groups_get_activity_groupmode($cm)) {
                  $groupid = groups_get_activity_group($cm);
                  // Determine is the group is visible to user (this is particullary for the group 0).
                  if (!groups_group_visible($groupid, $course, $cm)) {
                      throw new moodle_exception('notingroup');
                  }
              } else {
                  $groupid = 0;
              }
          }
  
          // Get the unique chat session id.
          // Since we are going to use the chat via Web Service requests we set the ajax version (since it's the most similar).
          if (!$chatsid = chat_login_user($chat->id, 'ajax', $groupid, $course)) {
              throw new moodle_exception('cantlogin', 'chat');
          }
  
          $result = array();
          $result['chatsid'] = $chatsid;
          $result['warnings'] = $warnings;
          return $result;
      }
code: public static function login_user($chatid, $groupid = 0) {
          global $DB;
  
          $params = self::validate_parameters(self::login_user_parameters(),
                                              array(
                                                  'chatid' => $chatid,
                                                  'groupid' => $groupid
                                              ));
          $warnings = array();
  
          // Request and permission validation.
          $chat = $DB->get_record('chat', array('id' => $params['chatid']), '*', MUST_EXIST);
          list($course, $cm) = get_course_and_cm_from_instance($chat, 'chat');
  
          $context = context_module::instance($cm->id);
          self::validate_context($context);
  
          require_capability('mod/chat:chat', $context);
  
          if (!empty($params['groupid'])) {
              $groupid = $params['groupid'];
              // Determine is the group is visible to user.
              if (!groups_group_visible($groupid, $course, $cm)) {
                  throw new moodle_exception('notingroup');
              }
          } else {
              // Check to see if groups are being used here.
              if ($groupmode = groups_get_activity_groupmode($cm)) {
                  $groupid = groups_get_activity_group($cm);
                  // Determine is the group is visible to user (this is particullary for the group 0).
                  if (!groups_group_visible($groupid, $course, $cm)) {
                      throw new moodle_exception('notingroup');
                  }
              } else {
                  $groupid = 0;
              }
          }
  
          // Get the unique chat session id.
          // Since we are going to use the chat via Web Service requests we set the ajax version (since it's the most similar).
          if (!$chatsid = chat_login_user($chat->id, 'ajax', $groupid, $course)) {
              throw new moodle_exception('cantlogin', 'chat');
          }
  
          $result = array();
          $result['chatsid'] = $chatsid;
          $result['warnings'] = $warnings;
          return $result;
      }
code_tokens: public static function login_user ( $ chatid , $ groupid = 0 ) { global $ DB ; $ params = self :: validate_parameters ( self :: login_user_parameters ( ) , array ( 'chatid' => $ chatid , 'groupid' => $ groupid ) ) ; $ warnings = array ( ) ; // Request and permission validation. $ chat = $ DB -> get_record ( 'chat' , array ( 'id' => $ params [ 'chatid' ] ) , '*' , MUST_EXIST ) ; list ( $ course , $ cm ) = get_course_and_cm_from_instance ( $ chat , 'chat' ) ; $ context = context_module :: instance ( $ cm -> id ) ; self :: validate_context ( $ context ) ; require_capability ( 'mod/chat:chat' , $ context ) ; if ( ! empty ( $ params [ 'groupid' ] ) ) { $ groupid = $ params [ 'groupid' ] ; // Determine is the group is visible to user. if ( ! groups_group_visible ( $ groupid , $ course , $ cm ) ) { throw new moodle_exception ( 'notingroup' ) ; } } else { // Check to see if groups are being used here. if ( $ groupmode = groups_get_activity_groupmode ( $ cm ) ) { $ groupid = groups_get_activity_group ( $ cm ) ; // Determine is the group is visible to user (this is particullary for the group 0). if ( ! groups_group_visible ( $ groupid , $ course , $ cm ) ) { throw new moodle_exception ( 'notingroup' ) ; } } else { $ groupid = 0 ; } } // Get the unique chat session id. // Since we are going to use the chat via Web Service requests we set the ajax version (since it's the most similar). if ( ! $ chatsid = chat_login_user ( $ chat -> id , 'ajax' , $ groupid , $ course ) ) { throw new moodle_exception ( 'cantlogin' , 'chat' ) ; } $ result = array ( ) ; $ result [ 'chatsid' ] = $ chatsid ; $ result [ 'warnings' ] = $ warnings ; return $ result ; }
docstring: Log the current user into a chat room in the given chat.
  
  @param int $chatid the chat instance id
  @param int $groupid the user group id
  @return array of warnings and the chat unique session id
  @since Moodle 3.0
  @throws moodle_exception
docstring_tokens: Log the current user into a chat room in the given chat .