<?php 
include_once 'function.php';
include_once 'service/CoursesController.php';
include_once 'service/UsersCoursesController.php';
include_once 'model/constantss_ui.php';
include_once 'model/constantss.php';
session_start();
if (validate_session_time_out() == 0) {
    header("Location:login.php");
    exit;
}
if ($_SESSION['change_password'] == 0) {
    header("Location:change_password.php");
    exit;
}
if (un_hash_val($_SESSION['current_user_type']) != constantss::$user_type_admin) {
    header("Location:main_page.php");
    exit;
}
if (isset($_SESSION['course'])) {
    $hashed_course_id = $_SESSION['course'];
} else {
    $hashed_course_id = -1;
}
if (isset($_SESSION['user_type'])) {
    $hashed_user_type = $_SESSION['user_type'];
} else {
    $hashed_user_type = -1;
}
$CoursesController = new CoursesController();
$UsersCoursesController = new UsersCoursesController();
        <br>
        <?php 
include 'header.php';
?>
        <br>
        <br>
        <div class="container">
            <div class="center_class">
                <div class="well">
                    <h3>
                        Hi, <?php 
echo $_SESSION['user_name'] . "...";
?>
 Theses are courses you <?php 
if (un_hash_val($_SESSION['current_user_type']) == constantss::$user_type_instructor) {
    echo "teaches";
} else {
    echo "have enrolled in";
}
?>
                    </h3></div> </div>
            <div class="list-group center_class" >
                <?php 
foreach ($courses as $course) {
    ?>
                    <h3> <a href= <?php 
    echo "\"course_materials.php?course=" . hash_val($course->get_course_id()) . "\"";
    ?>
 class="list-group-item"><div class="bg-primary"><?php 
    echo $course->get_course_name();
 public function remove_user($arr)
 {
     if ($this->hashed_course_id == -1) {
         return;
     }
     $unhashed_course_id = un_hash_val($this->hashed_course_id);
     $this->openDb();
     $arr_count = count($arr);
     for ($i = 0; $i < $arr_count; $i++) {
         //echo "delete from users_courses where user_id=$arr[$i] and course_id=$unhashed_course_id;" . "<br>";
         mysql_query("delete from users_courses where user_id='{$arr[$i]}' and course_id={$unhashed_course_id};") or die('<span class="error_span"><u>MySQL error:</u> ' . htmlspecialchars(mysql_error()) . '</span>');
     }
     $this->closeDb();
 }