language_loader.php

<?php
/**
 * file: language_loader.php
 *
 * Handles internationalization (i18n) by loading the appropriate language file.
 *
 * Determines the language based on URL parameter ('lang'), session data, or cookies.
 * Falls back to Dutch if no valid language is found.
 */

if (session_status() === PHP_SESSION_NONE) {
    session_start();
}

// Default language is Dutch
$default_lang = 'dutch';

// Check if a language is set in the session or cookie
if (isset($_GET['lang'])) {
    $lang_choice = $_GET['lang'];
    $_SESSION['lang'] = $lang_choice;
    setcookie('lang', $lang_choice, time() + (86400 * 30), "/"); // 30 day cookie
} elseif (isset($_SESSION['lang'])) {
    $lang_choice = $_SESSION['lang'];
} elseif (isset($_COOKIE['lang'])) {
    $lang_choice = $_COOKIE['lang'];
} else {
    $lang_choice = $default_lang;
}

// Check if the language file exists, otherwise fall back to the default
$lang_file = 'languages/' . $lang_choice . '.lang.inc.php';
if (!file_exists($lang_file)) {
    $lang_file = 'languages/' . $default_lang . '.lang.inc.php';
}

require_once $lang_file;
?>