feat: initial foundation for collaborative canteen ordering system in vanilla PHP

app/Core/Autoloader.php

@@ -0,0 +1,55 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Core;
+
+class Autoloader
+{
+    /**
+     * Map of namespace prefix to base directory
+     * @var array<string, string>
+     */
+    private static array $prefixes = [];
+
+    /**
+     * Register autoloader with SPL
+     */
+    public static function register(): void
+    {
+        spl_autoload_register([self::class, 'loadClass']);
+    }
+
+    /**
+     * Add a base directory for a namespace prefix
+     */
+    public static function addNamespace(string $prefix, string $baseDir): void
+    {
+        $prefix = trim($prefix, '\\') . '\\';
+        $baseDir = rtrim($baseDir, DIRECTORY_SEPARATOR) . DIRECTORY_SEPARATOR;
+        self::$prefixes[$prefix] = $baseDir;
+    }
+
+    /**
+     * Loads the class file for a given class name.
+     */
+    public static function loadClass(string $class): bool
+    {
+        foreach (self::$prefixes as $prefix => $baseDir) {
+            $len = strlen($prefix);
+            if (strncmp($prefix, $class, $len) !== 0) {
+                continue;
+            }
+
+            $relativeClass = substr($class, $len);
+            $file = $baseDir . str_replace('\\', DIRECTORY_SEPARATOR, $relativeClass) . '.php';
+
+            if (file_exists($file)) {
+                require_once $file;
+                return true;
+            }
+        }
+
+        return false;
+    }
+}