Course leaderboard

Leaderboard

class WPLMS_Course_Leaderboard{

    public static $instance;
    
    public static function init(){

        if ( is_null( self::$instance ) )
            self::$instance = new WPLMS_Course_Leaderboard();
        return self::$instance;
    }

    private function __construct(){
        add_filter('wplms_get_course_tabs',array($this,'add_course_tab'));
        add_filter('wplms_course_tab_data',array($this,'capture_course_id'),10,3);
        add_shortcode('course_leaderboard',array($this,'course_leaderboard'));
    }
    
    function add_course_tab($tabs){
        $tabs['internal__leaderboard'] = 'Leaderboard';
        return $tabs;
    }
    function capture_course_id($data,$body,$course_id){

        if($body['tab'] == 'internal__leaderboard'){
            $this->course_id = $course_id; // [1] CACHE the COURSE ID into this Class
            ob_start();            
            echo do_shortcode('[course_leaderboard course="'.$this->course_id.'"]');
            $data = ob_get_clean();
        }

        return $data;
    }

    function course_leaderboard($atts,$content=null){
        ob_start();
        global $wpdb;
        if(!isset($atts['count'])){
            $atts['count'] =10;
        }

        $students  =  $wpdb->get_results($wpdb->prepare("
                        SELECT pm.meta_key,pm.meta_value FROM {$wpdb->postmeta} AS pm
                        LEFT JOIN {$wpdb->posts} as p ON pm.post_id = p.ID
                        WHERE p.post_status = %s AND p.post_type = %s
                        AND p.ID = %d
                        AND pm.meta_key REGEXP '^[0-9]+$' ORDER BY pm.meta_value DESC LIMIT 0,{$atts['count']}",'publish','course',$atts['course'])
                    );

        if(!empty($students)){
            echo '<ul class="student_list_title">
                <li>
                    <span style="display: inline-block;background: #313b3d40;width: 50% !important;"> Student Name </span>
                    <span style="display: inline-block;background: #313b3d40;width: 49% !important;"> Marks </span>
                </li>
            </ul>';
            
            echo '<ol class="students">';
            foreach ($students as $key => $stu) {
                $student = get_user_by('id',$stu->meta_key);
                if(!empty($student) && !is_wp_error($student)){
                    echo '<li><span style="width: 50% !important;display: inline-block; font-size: 18px;">'.bp_core_get_user_displayname($student->ID).'</span><span style="width: 50% !important;display: inline-block; font-size: 18px;">'.$stu->meta_value.'</span></li>';
                }
            }
            echo '</ul>';
        }else{
            echo '<div class="vbp_message">No students found.</div>';
        }
        $html = ob_get_clean();
        return $html;
    }
        
  }
  
  WPLMS_Course_Leaderboard::init();