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// *************
// Check cookie!
// *************
function check_cookie(&$pun_user) {
    global $db, $pun_config, $cookie_name, $cookie_seed;

    $now = time();
    $expire = $now + 31536000;    // The cookie expires after a year

    // We assume it's a guest
    $cookie = array('user_id' => 1, 'password_hash' => 'Guest');

    // If a cookie is set, we get the user_id and password hash from it
    if (isset($_COOKIE[$cookie_name]))
    {
        list($cookie['user_id'], $cookie['password_hash']) = @unserialize($_COOKIE[$cookie_name]);

        if ($cookie['user_id'] > 1)
        {
        // Check if there's a user with the user ID and password hash from the cookie
        $result = $db->query('SELECT u.*, g.*, o.logged, o.idle FROM '.$db->prefix.'users AS u INNER JOIN '.$db->prefix.'groups AS g ON u.group_id=g.g_id LEFT JOIN '.$db->prefix.'online AS o ON o.user_id=u.id WHERE u.id='.intval($cookie['user_id'])) or error('Unable to fetch user information', __FILE__, __LINE__, $db->error());
        $pun_user = $db->fetch_assoc($result);

            // If user authorisation failed
            if (!isset($pun_user['id']) || md5($cookie_seed.$pun_user['password']) !== $cookie['password_hash'])
            {
            pun_setcookie(0, random_pass(8), $expire);
            set_default_user();
            return;
            }

        // Set a default language if the user selected language no longer exists
        if (!@file_exists(PUN_ROOT.'lang/'.$pun_user['language']))
            { $pun_user['language'] = $pun_config['o_default_lang']; }

        // Set a default style if the user selected style no longer exists
        if (!@file_exists(PUN_ROOT.'style/'.$pun_user['style'].'.css'))
            { $pun_user['style'] = $pun_config['o_default_style']; }

        if (!$pun_user['disp_topics'])
            { $pun_user['disp_topics'] = $pun_config['o_disp_topics_default'];}
        if (!$pun_user['disp_posts'])
            { $pun_user['disp_posts'] = $pun_config['o_disp_posts_default'];}

        if ($pun_user['save_pass'] == '0')
            { $expire = 0; }

        // Define this if you want this visit to affect the online list and the users last visit data
        if (!defined('PUN_QUIET_VISIT'))
        {
            // Update the online list
            if (!$pun_user['logged'])
            {
                $db->query('INSERT INTO '.$db->prefix.'online (user_id, ident, logged) VALUES('.$pun_user['id'].', \''.$db->escape($pun_user['username']).'\', '.$now.')') or error('Unable to insert into online list', __FILE__, __LINE__, $db->error());
            }
            else
            {
                // Special case: We've timed out, but no other user has browsed the forums since we timed out
                if ($pun_user['logged'] < ($now-$pun_config['o_timeout_visit']))
                {
                    $db->query('UPDATE '.$db->prefix.'users SET last_visit='.$pun_user['logged'].' WHERE id='.$pun_user['id']) or error('Unable to update user visit data', __FILE__, __LINE__, $db->error());
                    $pun_user['last_visit'] = $pun_user['logged'];
                }
            }

                $idle_sql = ($pun_user['idle'] == '1') ? ', idle=0' : '';
                $db->query('UPDATE '.$db->prefix.'online SET logged='.$now.$idle_sql.' WHERE user_id='.$pun_user['id']) or error('Unable to update online list', __FILE__, __LINE__, $db->error());
            }
        }

        $pun_user['is_guest'] = false;
    }
    else
    { 
    set_default_user();
    }
}