PHP - Router

<?php

class Router {
    public $url_array;
    public $arguments;

    public function __construct(){
        $this->url_array = parse_url($_SERVER['REQUEST_URI'])['path'];
        $this->arguments = array_filter(explode("/", $this->url_array));
        $this->includeNecessaryFile();
    }

    public function includeNecessaryFile(){
    if(count($this->arguments) > 0){
        if(file_exists("main/".$this->arguments[1].".php") && $this->arguments[1] !== 'index'){
            require("main/".$this->arguments[1].".php");
            // any excess arguments are stored in Router.arguments and can be accessed by the included file using $this
        }
    }   else {
            require("main/index.php");
        }
    }
}


$index_router = new Router();