/**
  * Return active instance of WP_Stream_Reports, create one if it doesn't exist
  *
  * @return WP_Stream_Reports
  */
 public static function get_instance()
 {
     if (empty(self::$instance)) {
         $class = __CLASS__;
         self::$instance = new $class();
     }
     return self::$instance;
 }
function wp_stream_reports_intervals_html()
{
    $date = WP_Stream_Reports_Date_Interval::get_instance();
    // Default interval
    $default = array('key' => 'all-time', 'start' => '', 'end' => '');
    $user_interval = WP_Stream_Reports_Settings::get_user_options('interval', $default);
    $save_interval_url = add_query_arg(array_merge(array('action' => 'wp_stream_reports_save_interval'), WP_Stream_Reports::$nonce), admin_url('admin-ajax.php'));
    include WP_STREAM_REPORTS_VIEW_DIR . 'intervals.php';
}