PHP router

router.php

<?php
  $uri = $_SERVER['REQUEST_URI'];

  # Serve static ressources.
  if (preg_match('/\.(?:png|jpg|jpeg|gif|css|js|svg)$/', $uri)) {
    return false;
  }

  function register($method, $route, $callback) {
    global $uri;

    preg_match_all('/:([^\/]+)/', $route, $matches, PREG_SET_ORDER);
    $pattern = preg_replace('/:[^\/]+/', '([^/]+)', $route);
    $pattern = preg_replace('/\//', '\\/', $pattern);
    $pattern = "/^$pattern\/?$/";

    if ($method == $_SERVER['REQUEST_METHOD'] &&
        preg_match_all($pattern, $uri, $matches, PREG_SET_ORDER)) {
      $callback(...array_slice($matches[0], 1));
      die();
    }
  }

  function redirect($url) {
    return function () use ($url) {
      header('Location: ' . $url);
    };
  }

  function view($path) {
    return function () use ($path) {
      require __DIR__ . $path . '.php';
    };
  }

  register('GET', '/', view('/pages/index'));
  register('GET', '/contact', view('/pages/contact'));
  register('GET', '/photos', redirect('/photos/2020'));
  register('GET', '/photos/:year', function ($year) {
    require __DIR__ . '/photos/index.php';
  });

  die('404');
?>