Created captcha type (this works, but still no image generation)

Validator/CaptchaValidator.php

@@ -0,0 +1,64 @@
+<?php
+
+namespace Gregwar\CaptchaBundle\Validator;
+
+use Symfony\Component\Form\FormValidatorInterface;
+use Symfony\Component\HttpFoundation\Session;
+use Symfony\Component\Form\FormInterface;
+use Symfony\Component\Form\FormError;
+
+/**
+ * Captcha validator
+ *
+ * @author Gregwar <g.passault@gmail.com>
+ */
+class CaptchaValidator implements FormValidatorInterface
+{
+    /**
+     * Session
+     */
+    private $session;
+
+    /**
+     * Session key to store the code
+     */
+    private $key;
+
+    public function __construct(Session $session, $key)
+    {
+        $this->session = $session;
+        $this->key = $key;
+    }
+
+    public function validate(FormInterface $form)
+    {
+        $code = $form->getData();
+        $excepted_code = $this->getExceptedCode();
+
+        if (!($code && $excepted_code && is_string($code) && is_string($excepted_code)
+            && $this->niceize($code) == $this->niceize($excepted_code))) {
+            $form->addError(new FormError('Bad code value'));
+        }
+
+        $this->session->remove($this->key);
+    }
+
+    /**
+     * Retrieve the excepted CAPTCHA code
+     */
+    private function getExceptedCode()
+    {
+        if ($this->session->has($this->key)) {
+            return $this->session->get($this->key);
+        }
+        return null;
+    }
+
+    /**
+     * Process the codes
+     */
+    private function niceize($code) 
+    {
+        return strtr($code, 'oil', '01l');
+    }
+}