/* comment_mail_notify v1.0 by willin kan. (reply all comments) */
function comment_mail_notify($comment_id) {
  $comment = get_comment($comment_id);
  $parent_id = $comment->comment_parent ? $comment->comment_parent : '';
  $spam_confirmed = $comment->comment_approved;
  if (($parent_id != '') && ($spam_confirmed != 'spam')) {
    $wp_email = 'wordpress@' . preg_replace('#^www\.#', '', strtolower($_SERVER['SERVER_NAME']));	//from email address
    $to = trim(get_comment($parent_id)->comment_author_email);	//to email address
    $subject = '您在 [' . get_option("blogname") . '] 的留言有了回应';
    $message = '
    <div style="background-color:#eef2fa; border:1px solid #d8e3e8; color:#111; padding:0 15px; -moz-border-radius:5px; -webkit-border-radius:5px; -khtml-border-radius:5px;">
      <p>' . trim(get_comment($parent_id)->comment_author) . ', 您好!</p>
      <p>您曾在《' . get_the_title($comment->comment_post_ID) . '》的留言:<br /><b>'
       . trim(get_comment($parent_id)->comment_content) . '</b></p>
      <p>' . trim($comment->comment_author) . ' 给您的回应:<br /><b>'
       . trim($comment->comment_content) . '</b><br /></p>
      <p>您可以点击 <a href="' . htmlspecialchars(get_comment_link($parent_id)) . '">查看回应完整內容</a></p>
      <p>欢迎再次访问 <a href="' . get_option('home') . '"><b>' . get_option('blogname') . '</b></a></p>
      <p><b>注：此邮件由系统发出，但您的回复将发送至我的收件箱。</b></p>
    </div>';
    $from = "From: \"" . get_option('blogname') . "\" <$wp_email>";
    $headers = "$from\nContent-Type: text/html; charset=" . get_option('blog_charset') . "\n";
    wp_mail( $to, $subject, $message, $headers );
  }
}
add_action('comment_post', 'comment_mail_notify');