Introduce captcha session service

[MAILPOET-2248]

lib/DI/ContainerConfigurator.php

@@ -163,6 +163,7 @@ class ContainerConfigurator implements IContainerConfigurator {
     // Subscription
     $container->autowire(\MailPoet\Subscription\Captcha::class)->setPublic(true);
     $container->autowire(\MailPoet\Subscription\CaptchaRenderer::class)->setPublic(true);
+    $container->autowire(\MailPoet\Subscription\CaptchaSession::class);
     $container->autowire(\MailPoet\Subscription\Comment::class)->setPublic(true);
     $container->autowire(\MailPoet\Subscription\Form::class)->setPublic(true);
     $container->autowire(\MailPoet\Subscription\Manage::class)->setPublic(true);

lib/Subscription/CaptchaSession.php

@@ -0,0 +1,56 @@
+<?php
+
+namespace MailPoet\Subscription;
+
+use MailPoet\Config\Session;
+use MailPoet\WP\Functions as WPFunctions;
+
+class CaptchaSession {
+  const EXPIRATION = 300; // 5 minutes
+
+  const SESSION_HASH_KEY = 'hash';
+  const SESSION_FORM_KEY = 'form';
+
+  /** @var WPFunctions */
+  private $wp;
+
+  /** @var Session */
+  private $session;
+
+  function __construct(WPFunctions $wp, Session $session) {
+    $this->wp = $wp;
+    $this->session = $session;
+  }
+
+  function isAvailable() {
+    return $this->session->getId() !== null;
+  }
+
+  function reset() {
+    $this->wp->deleteTransient($this->getKey(self::SESSION_FORM_KEY));
+    $this->wp->deleteTransient($this->getKey(self::SESSION_HASH_KEY));
+  }
+
+  function setFormData(array $data) {
+    $this->wp->setTransient($this->getKey(self::SESSION_FORM_KEY), $data, self::EXPIRATION);
+  }
+
+  function getFormData() {
+    return $this->wp->getTransient($this->getKey(self::SESSION_FORM_KEY));
+  }
+
+  function setCaptchaHash($hash) {
+    $this->wp->setTransient($this->getKey(self::SESSION_HASH_KEY), $hash, self::EXPIRATION);
+  }
+
+  function getCaptchaHash() {
+    return $this->wp->getTransient($this->getKey(self::SESSION_HASH_KEY));
+  }
+
+  private function getKey($type) {
+    if ($this->session->getId() === null) {
+      throw new \Exception("MailPoet session not initialized.");
+    }
+    return implode('_', ['MAILPOET', $this->session->getId(), $type]);
+  }
+}

lib/WP/Functions.php

@@ -384,6 +384,14 @@ class Functions {
     return set_transient($transient, $value, $expiration);
   }
 
+  function getTransient($transient) {
+    return get_transient($transient);
+  }
+
+  function deleteTransient($transient) {
+    return delete_transient($transient);
+  }
+
   function singlePostTitle($prefix = '', $display = true) {
     return single_post_title($prefix, $display);
   }