Implement toggle in main controller.

public/index.php

@@ -1,7 +1,22 @@
 <?php
 require_once '../vendor/autoload.php';
 
-if (\FooBar\Configuration::loadConfig()->isOpen()) {
+$config = \FooBar\Configuration::loadConfig();
+
+if (isset($_POST['auth_check'])) {
+    if (!$config->isAuthorized()) {
+        http_response_code(403);
+    }
+} elseif (isset($_POST['toggle']) && $config->isAuthorized()) {
+    $file = $config->stateFile();
+    if ($config->isOpen()) {
+        unlink($file);
+    } else {
+        touch($file);
+    }
+}
+
+if ($config->isOpen()) {
     require '../templates/open.html';
 } else {
     require '../templates/closed.html';