<?php

/**
 * CodeIgniter
 *
 * An open source application development framework for PHP
 *
 * This content is released under the MIT License (MIT)
 *
 * Copyright (c) 2019 - 2022, CodeIgniter Foundation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * @package CodeIgniter
 * @author  EllisLab Dev Team
 * @copyright   Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
 * @copyright   Copyright (c) 2014 - 2019, British Columbia Institute of Technology (https://bcit.ca/)
 * @copyright   Copyright (c) 2019 - 2022, CodeIgniter Foundation (https://codeigniter.com/)
 * @license https://opensource.org/licenses/MIT MIT License
 * @link    https://codeigniter.com
 * @since   Version 3.0.0
 * @filesource
 */

defined('BASEPATH') or exit('No direct script access allowed');

/**
 * CodeIgniter Session Driver Class
 *
 * @package CodeIgniter
 * @subpackage  Libraries
 * @category    Sessions
 * @author  Andrey Andreev
 * @link    https://codeigniter.com/userguide3/libraries/sessions.html
 */
abstract class CI_Session_driver
{
    protected $_config;

    /**
     * Data fingerprint
     *
     * @var bool
     */
    protected $_fingerprint;

    /**
     * Lock placeholder
     *
     * @var mixed
     */
    protected $_lock = false;

    /**
     * Read session ID
     *
     * Used to detect session_regenerate_id() calls because PHP only calls
     * write() after regenerating the ID.
     *
     * @var string
     */
    protected $_session_id;

    /**
     * Success and failure return values
     *
     * Necessary due to a bug in all PHP 5 versions where return values
     * from userspace handlers are not handled properly. PHP 7 fixes the
     * bug, so we need to return different values depending on the version.
     *
     * @see https://wiki.php.net/rfc/session.user.return-value
     * @var mixed
     */
    protected $_success;
    protected $_failure;

    // ------------------------------------------------------------------------

    /**
     * Class constructor
     *
     * @param   array   $params Configuration parameters
     * @return  void
     */
    public function __construct(&$params)
    {
        $this->_config = & $params;

        if (is_php('7')) {
            $this->_success = true;
            $this->_failure = false;
        } else {
            $this->_success = 0;
            $this->_failure = -1;
        }
    }

    // ------------------------------------------------------------------------

    /**
     * PHP 5.x validate ID
     *
     * Enforces session.use_strict_mode
     *
     * @return  void
     */
    public function php5_validate_id()
    {
        if ($this->_success === 0 && isset($_COOKIE[$this->_config['cookie_name']]) && ! $this->validateId($_COOKIE[$this->_config['cookie_name']])) {
            unset($_COOKIE[$this->_config['cookie_name']]);
        }
    }

    // ------------------------------------------------------------------------

    /**
     * Cookie destroy
     *
     * Internal method to force removal of a cookie by the client
     * when session_destroy() is called.
     *
     * @return  bool
     */
    protected function _cookie_destroy()
    {
        if (! is_php('7.3')) {
            $header = 'Set-Cookie: ' . $this->_config['cookie_name'] . '=';
            $header .= '; Expires=' . gmdate('D, d-M-Y H:i:s T', 1) . '; Max-Age=-1';
            $header .= '; Path=' . $this->_config['cookie_path'];
            $header .= ($this->_config['cookie_domain'] !== '' ? '; Domain=' . $this->_config['cookie_domain'] : '');
            $header .= ($this->_config['cookie_secure'] ? '; Secure' : '') . '; HttpOnly; SameSite=' . $this->_config['cookie_samesite'];
            header($header);
            return;
        }

        return setcookie(
            $this->_config['cookie_name'],
            '',
            array(
                'expires' => 1,
                'path' => $this->_config['cookie_path'],
                'domain' => $this->_config['cookie_domain'],
                'secure' => $this->_config['cookie_secure'],
                'httponly' => true,
                'samesite' => $this->_config['cookie_samesite']
            )
        );
    }

    // ------------------------------------------------------------------------

    /**
     * Get lock
     *
     * A dummy method allowing drivers with no locking functionality
     * (databases other than PostgreSQL and MySQL) to act as if they
     * do acquire a lock.
     *
     * @param   string  $session_id
     * @return  bool
     */
    protected function _get_lock($session_id)
    {
        $this->_lock = true;
        return true;
    }

    // ------------------------------------------------------------------------

    /**
     * Release lock
     *
     * @return  bool
     */
    protected function _release_lock()
    {
        if ($this->_lock) {
            $this->_lock = false;
        }

        return true;
    }
}