navbar.php

 <!-- default authentical routing -->
 <?php
  include "auth.php";
  $visible = json_decode($_COOKIE["user_data"])[3] === 'admin' ? 'block' : 'none';
  ?>

 <div id="mySidenav" class="sidenav">
   <div id="avatar" class="mt-4 mb-2">
     <img src="./backend/uploads/<?php echo json_decode($_COOKIE["user_data"])[2]; ?>" height="100%" width="100%" onclick="redirectHomepage()" />
   </div>
   <center>
     <span>
       <?php
        if ($visible === "block") {
          echo "Admin Panel";
          $issue_type = "Issued";
          $issue_url = "issued.php";
          $display_user_issued = "none";
        } else if (json_decode($_COOKIE["user_data"])[3] === 'member') {
          echo "Member Panel";
          $issue_type = "Reserved";
          $issue_url = "reserved.php";
          $display_user_issued = "block";
        } else {
          echo "User Panel";
          $issue_type = "Reserved";
          $issue_url = "reserved.php";
          $display_user_issued = "block";
        }
        ?>
     </span>
   </center>
   <hr />
   <a href="javascript:void(0)" class="closebtn" onclick="closeNav()">&times;</a>
   <a href="index.php"> <i class="fa fa-home" aria-hidden="true"></i> Dashboard</a>
   <a href="members.php" class="d-<?php echo $visible; ?>"> <i class="fa fa-users" aria-hidden="true"></i> Members</a>
   <a href="users.php" class="d-<?php echo $visible; ?>"> <i class="fa fa-users" aria-hidden="true"></i> Users</a>
   <a href="books.php"> <i class="fa fa-book" aria-hidden="true"></i> Books</a>
   <a href="<?php echo $issue_url; ?>"> <i class="fa fa-rocket" aria-hidden="true"></i> <?php echo $issue_type; ?></a>
   <a href="reserved.php" class="d-<?php echo $visible; ?>"> <i class="fa fa-book" aria-hidden="true"></i> Reserved Books</a>
   <a href="user_issued_books.php" class="d-<?php echo $display_user_issued; ?>"> <i class="fa fa-undo" aria-hidden="true"></i> Issued Book</a>
   <a href="returned.php" class="d-<?php echo $visible; ?>"> <i class="fa fa-undo" aria-hidden="true"></i> Returned</a>
   <a href="delay.php" class="d-<?php echo $visible; ?>"> <i class="fa fa-exclamation-circle" aria-hidden="true"></i> Not Returned</a>
   <a href="setting.php"> <i class="fa fa-cogs" aria-hidden="true"></i> Setting</a>
 </div>

 <!-- Use any element to open the sidenav -->
 <div class="fixed-top" id="navbar">
   <div id="rightNav">
     <i onclick="openNav()" class="fa fa-bars" aria-hidden="true"></i>
     <img src="./img/logo.png" onclick="redirectHomepage()" />
   </div>
   <div id="leftNav">
     <?php
      if (json_decode($_COOKIE["user_data"])[3] === "admin") {
      ?>
       <i class="fa fa-plus" data-bs-toggle="tooltip" data-bs-placement="top" title="Add a new book" onclick="createBook()" draggable="false"></i>
     <?php } ?>
     <!-- <img src="./img/paint.png" height="28px" width="28px" data-bs-toggle="tooltip" data-bs-placement="top" title="Change BG color" aria-hidden="true" onclick="changeBackground()" draggable="false"></i> -->
     <img id="avatar" src="./backend/uploads/<?php echo json_decode($_COOKIE["user_data"])[2]; ?>" height="100%" width="100%" onclick="showProfile_nav()" draggable="false" />
   </div>
 </div>
 <script>
   function redirectHomepage() {
     location.assign("http://localhost/elibrary/")
   }
 </script>



 <!-- if (json_decode($_COOKIE["user_data"])[3] === "admin") {

   <i class="fa fa-plus" data-bs-toggle="tooltip" data-bs-placement="top" title="Add a new book" onclick="createBook()" draggable="false"></i> -->