Request.class.php

<?php
# Lifter007: TODO
/*
 * Request.php - class representing a HTTP request in Stud.IP
 *
 * Copyright (c) 2009  Elmar Ludwig
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 */

/**
 * Singleton class representing a HTTP request in Stud.IP.
 */
class Request implements ArrayAccess, IteratorAggregate
{
    /**
     * cached request parameter array
     */
    private $params;

    /**
     * Initialize a new Request instance.
     */
    private function __construct()
    {
        $this->params = array_merge($_GET, $_POST);
    }

    /**
     * Return the Request singleton instance.
     */
    public static function getInstance()
    {
        static $instance;

        if (isset($instance)) {
            return $instance;
        }

        return $instance = new Request();
    }

    /**
     * ArrayAccess: Check whether the given offset exists.
     *
     * @todo Add bool return type when Stud.IP requires PHP8 minimal
     */
    #[ReturnTypeWillChange]
    public function offsetExists($offset)
    {
        return isset($this->params[$offset]);
    }

    /**
     * ArrayAccess: Get the value at the given offset.
     *
     * @todo Add mixed return type when Stud.IP requires PHP8 minimal
     */
    #[ReturnTypeWillChange]
    public function offsetGet($offset)
    {
        return $this->params[$offset] ?? null;
    }

    /**
     * ArrayAccess: Set the value at the given offset.
     *