driver function

    private function run_driver($driver_core, $driver_name, $func_name, $params=array()){
        // log_add("run driver: $driver_core| $driver_name| $func_name");
        // log_add("parameter:".count($params));
/*  Kita butuh config khusus untuk daftar driver */
        $config_file='driver_gw';
        if(!is_file(APPPATH.'config/'.$config_file.".php")){
            // log_add('buatlah confignya di:'.APPPATH.'config/'.$config_file.".php",'error');
            return  'buatlah confignya di:'.APPPATH.'config/'.$config_file.".php" ;
        }

        $this->config->load($config_file);
        $valid_drivers= $this->config->item('drivers_'.$driver_core);
        if(is_null($valid_drivers)||$valid_drivers===false){
            // log_add("buatlah array confignya \$config['drivers_{$driver_core}']=array();",'error');
            return  "buatlah array confignya \$config['drivers_{$driver_core}']=array();" ;
        }

        if(!in_array($driver_name,$valid_drivers)){
            // log_add("buatlah nilai '{$driver_name}' pada array confignya \$config['drivers_{$driver_core}']=array('{$driver_name}');",'error');
            return  "buatlah nilai '{$driver_name}' pada array confignya \$config['drivers_{$driver_core}']=array('{$driver_name}');" ;
        }
/* keberadaan file driver */
        $core_file=ucfirst(strtolower($driver_core));
        $driver_file=ucfirst(strtolower($driver_core))."_".strtolower($driver_name);
        if(!is_file(APPPATH.'libraries/'.$core_file.'/drivers/'.$driver_file.".php")){
            // log_add('buatlah file drivernya di:'.APPPATH.'libraries/'.$core_file.'/drivers/'.$driver_file.".php",'error');
            return  'buatlah file drivernya di:'.APPPATH.'libraries/'.$core_file.'/drivers/'.$driver_file.".php" ;
        }

        $result=false;
        if( !method_exists($this->{$driver_core}->{$driver_name},$func_name) ){
            // log_add('buatlah fungsi '.$func_name.'($params) pada file drivernya di:'.APPPATH.'libraries/'.$core_file.'/drivers/'.$driver_file.".php",'error');
            return  'buatlah fungsi '.$func_name.'($params) pada file drivernya di:'.APPPATH.'libraries/'.$core_file.'/drivers/'.$driver_file.".php" ;
        }
        else{
            $row=$params=false;
            $params=$this->{$driver_core}->{$driver_name}->{$func_name}($row);
            return $params;
        }

        return $result;
    }