如何在PHP Store Hours插件中添加“特殊消息”

I downloaded the PHP Store hours plugin and been messing around with it trying to implement a message to certain dates - in a similar fashion and the exceptions work. But for the life of me I can't figure it out.

The idea would be to assign a message/greeting to a specific date and print it out below the hours.

Here's the functions file:

    <?php 

// ----------------------------------
// PHP STORE HOURS
// ----------------------------------
// Version 3.0
// Written by Cory Etzkorn
// https://github.com/coryetzkorn/php-store-hours

// DO NOT MODIFY THIS CLASS FILE

class StoreHours {

  function __construct($hours = array(), $exceptions = array(), $template = array()) {
    $this->hours = $hours;
    $this->exceptions = $exceptions;
    $this->template = $template;
    if(!isset($this->template['open'])) {
      $this->template['open'] = "<h3>Yes, we're open! Today's hours are {%hours%}.</h3>";
    }
    if(!isset($this->template['closed'])) {
      $this->template['closed'] = "<h3>Sorry, we're closed. Today's hours are {%hours%}.</h3>";
    }
    if(!isset($this->template['closed_all_day'])) {
      $this->template['closed_all_day'] = "<h3>Sorry, we're closed.</h3>";
    }
    if(!isset($this->template['separator'])) {
      $this->template['separator'] = " - ";
    }
    if(!isset($this->template['join'])) {
      $this->template['join'] = " and ";
    }
    if(!isset($this->template['format'])) {
      $this->template['format'] = "g:ia";
    }
    if(!isset($this->template['hours'])) {
      $this->template['hours'] = "{%open%}{%separator%}{%closed%}";
    }
  }

  // Returns today's hours
  public function hours_today() {
    $today = strtotime('today midnight');
    $day = strtolower(date("D"));
    $exceptions = $this->exceptions;
    $hours_today = $this->hours[$day];
    if($exceptions) {
      foreach($exceptions as $ex_day => $ex_hours) {
        //echo 'ex' . date('r', strtotime($ex_day + '/2014'));
        //echo 'today' . date('r', $today);
        if(strtotime($ex_day) == $today) {
          // Today is an exception, use alternate hours instead
          $hours_today = $ex_hours;
        }
      }
    }
    return $hours_today;
  }

  // Returns boolean
  public function is_open() {
    $now = strtotime(date("G:i"));
    $hours_today = $this->hours_today();
    $exceptions = $this->exceptions;
    $is_open = 0;
    if(!empty($hours_today[0])) {
      foreach($hours_today as $range) {
        $range = explode("-", $range);
        $start = strtotime($range[0]);
        $end = strtotime($range[1]);
        // Add one day if the end time is past midnight
        if($end <= $start) {
          $end = strtotime($range[1] . ' + 1 day');
        }
        if (($start <= $now) && ($end >= $now)) {
          $is_open ++;
        }
      }
    }
    if($is_open > 0) {
      return true;
    } else {
      return false;
    }
  }

  // Prep HTML
  private function render_html($template_name) {
    $template = $this->template;
    $hours_today = $this->hours_today();
    $output = '';
    $index = 0;
    if(!empty($hours_today[0])) {
      $hours_template = '';
      foreach($hours_today as $range) {
        $range = explode("-", $range);
        $start = strtotime($range[0]);
        $end = strtotime($range[1]);
        if($index >= 1) {
          $hours_template .= $template['join'];
        }
        $hours_template .= $template['hours'];
        $hours_template = str_replace('{%open%}', date($template['format'], $start), $hours_template);
        $hours_template = str_replace('{%closed%}', date($template['format'], $end), $hours_template);
        $hours_template = str_replace('{%separator%}', $template['separator'], $hours_template);
        $index ++;
      }
      $output .= str_replace('{%hours%}', $hours_template, $template[$template_name]);
    } else {
      $output .= $template['closed_all_day'];
    }
    echo $output;
  }

  // Output HTML
  public function render() {
    if($this->is_open()) {
      $this->render_html('open');
    } else {
      $this->render_html('closed');
    }
  }

}

?>

Here's what I have it printing out:

    <?php 
        // REQUIRED
        // Set your default time zone (listed here: http://php.net/manual/en/timezones.php)
        date_default_timezone_set('America/New_York'); 
        // Include the store hours class
        require_once('hours.php');

        // REQUIRED
        // Define daily open hours
      // Must be in 24-hour format, separated by dash 
      // If closed for the day, leave blank (ex. sunday)
      // If open multiple times in one day, enter time ranges separated by a comma
      $hours = array(
          'mon' => array('9:00am - 5:00pm'),
          'tue' => array('9:00am - 5:00pm'),
          'wed' => array('9:00am - 5:00pm'), 
          'thu' => array('9:00am - 5:00pm'),
          'fri' => array('9:00am - 5:00pm'),
          'sat' => array('9:30am - 3:30pm'),
          'sun' => array('') // Closed all day
        );

      // OPTIONAL
      // Add exceptions (great for holidays etc.)
      // MUST be in format month/day
      // Do not include the year if the exception repeats annually
      $exceptions = array(
        '12/25' => array('9:00am - 1:00pm'),
        '1/1' => array('9:00am - 1:00pm')
      );
    ?>

    <?php
    $template = array(
        'open'  => "<div class=\"hours-open\">
                    <p class=\"hours uppercase white\">Yes, we are open!</p> 
                    <p class=\"hours\">From {%hours%}.</p>
                    </div>",
        'closed'=> "<div class=\"hours-closed\">
                    <p class=\"hours uppercase white\">Sorry, we are closed.</p>
                    <p class=\"hours\">Today's hours: {%hours%}.</p>
                    </div>",
        'closed_all_day'=> "<div class=\"hours-closed\">
                    <p class=\"hours uppercase white\">Sorry, we're closed today.</p>
                    </div>",
        'separator'     => " - ",
        'join'          => " and ",
        'format'        => "g:ia",
        'hours'         => "{%open%}{%separator%}{%closed%}"
    );

    $store_hours = new StoreHours($hours, $exceptions, $template);
    $store_hours->render();
?>