Fix attempt to restore closed chat in popup

src/mibew/configs/routing.yml

@@ -49,6 +49,14 @@ chat_user:
         thread_id: \d{1,10}
         token: \d{1,10}
 
+chat_user_check:
+    path: /chat/{thread_id}/{token}/check
+    defaults:
+        _controller: Mibew\Controller\Chat\UserChatController::checkAction
+    requirements:
+        thread_id: \d{1,10}
+        token: \d{1,10}
+
 chat_user_invitation:
     path: /chat/invitation
     defaults:

src/mibew/js/source/chat_popup.js

@@ -333,7 +333,7 @@ var Mibew = Mibew || {};
         if (openedChatUrl) {
             // The chat was not closed so the popup should be reopened when a
             // new page is visited.
-            this.open(openedChatUrl);
+            this.safeOpen(openedChatUrl);
             // Check minification status of the popup and toggle it if needed.
             var minifiedPopup = Mibew.Utils.readCookie('mibew-chat-frame-minified-' + this.id);
             if (minifiedPopup === 'true') {
@@ -430,6 +430,24 @@ var Mibew = Mibew || {};
         this.isOpened = true;
     };
 
+    /**
+     * Check chat URL via special request, open the chat if check passes,
+     * close the popup if the check fails.
+     *
+     * @param {String} [url] The URL to open in the popup
+     */
+    Mibew.ChatPopup.IFrame.prototype.safeOpen = function(url) {
+        var check = Mibew.Utils.loadScript(url + '/check', 'mibew-check-iframe-' + this.id);
+        check.popup = this;
+        check.url = url;
+        check.onload = function(){
+            this.popup.open(this.url);
+        }
+        check.onerror = function(){
+            this.popup.close();
+        };
+    };
+
     /**
      * Closes the popup.
      */

src/mibew/libs/classes/Mibew/Controller/Chat/UserChatController.php

@@ -74,6 +74,31 @@ class UserChatController extends AbstractController
         return $this->render('chat', $page);
     }
 
+    /**
+     * Check chat to exists.
+     *
+     * @param Request $request Incoming request.
+     * @return string Empty string.
+     * @throws NotFoundException If the thread with specified ID and token is
+     * not found.
+     */
+    public function checkAction(Request $request)
+    {
+        $thread_id = $request->attributes->getInt('thread_id');
+        $token = $request->attributes->get('token');
+
+        // We have to check that the thread is owned by the user.
+        $is_own_thread = isset($_SESSION[SESSION_PREFIX . 'own_threads'])
+            && in_array($thread_id, $_SESSION[SESSION_PREFIX . 'own_threads']);
+
+        $thread = Thread::load($thread_id, $token);
+        if (!$thread || !$is_own_thread) {
+            throw new NotFoundException('The thread is not found.');
+        }
+
+        return "";
+    }
+
     /**
      * Starts the chat.
      *