Login integration: Logging in on an existing site and punBB (Page 2 of 2)

define('FORUM_ROOT', './punbb/');
include 'punbb/include/common.php';    //Include this file so that $pun_user['is_guest'] can be used and that (some?) functions from punbb/include/functions.php can also be used in this script


if (($websitelogin==true) && ($pun_users['is_guest'])) {
    
    $username = $user->Username;  //Get the username of the logged in user and put it in a variable     ($user->Username comes from code from the website which is intended to get login integration with punbb through this script)
    
    $queryFromPunbb = "SELECT * FROM pun_users WHERE username='$username'";    //get the row with the id from the logged in user. This id is the primary key of the punbb_users table in the punbb database
    $result = mysql_query($queryFromPunbb, $conn) or die (mysql_error());    //Run the query
    $row = mysql_fetch_array($result) or die(mysql_error());    //Put the result of the query in an array called $row  
    
    $user_id = $row['id'];    //Put the id from the $row array into the variable $user_id
    $hashedPassword = forum_hash($user->password);    //hash the user's password using the punbb hash function 
    $expirationTime = time()+24*60*60;
    
    forum_setcookie($user_id, $hashedPassword, $expirationTime);  //Set the punBB cookie, which is called punbb_cookie
    

header("Location: ./punbb"); //send the browser to the /punbb directory
}
elseif (($websitelogin==true) && !($pun_users['is_guest'])) {
    header("Location: ./punbb"); //send the browser to the /punbb directory
}
elseif (!($websitelogin) && ($pun_users['is_guest'])) {
    header("Location: ./punbb"); //send the browser to the /punbb directory
}