From 5479aea9f0f5f38be0aa300aed804b86bbb5f116 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?David=20N=C3=A9grier?= <d.negrier@thecodingmachine.com>
Date: Tue, 26 Apr 2022 14:40:54 +0200
Subject: [PATCH] Preventing a loop from occuring with chat API

When sending a chat message from the Scripting API, the chat message is no longer sent back to the chat listener.
This makes it easier to avoid infinite loops.
---
 front/src/Api/IframeListener.ts | 15 +++++++++++----
 front/src/Api/ScriptUtils.ts    |  4 ++--
 front/src/Stores/ChatStore.ts   |  7 +++++--
 3 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/front/src/Api/IframeListener.ts b/front/src/Api/IframeListener.ts
index 345f3b41..f9f2b634 100644
--- a/front/src/Api/IframeListener.ts
+++ b/front/src/Api/IframeListener.ts
@@ -239,7 +239,7 @@ class IframeListener {
                     } else if (iframeEvent.type === "cameraFollowPlayer") {
                         this._cameraFollowPlayerStream.next(iframeEvent.data);
                     } else if (iframeEvent.type === "chat") {
-                        scriptUtils.sendAnonymousChat(iframeEvent.data);
+                        scriptUtils.sendAnonymousChat(iframeEvent.data, iframe.contentWindow ?? undefined);
                     } else if (iframeEvent.type === "openPopup") {
                         this._openPopupStream.next(iframeEvent.data);
                     } else if (iframeEvent.type === "closePopup") {
@@ -399,13 +399,17 @@ class IframeListener {
         this.scripts.delete(scriptUrl);
     }
 
-    sendUserInputChat(message: string) {
+    /**
+     * @param message The message to dispatch
+     * @param exceptOrigin Don't dispatch the message to exceptOrigin (to avoid infinite loops)
+     */
+    sendUserInputChat(message: string, exceptOrigin?: Window) {
         this.postMessage({
             type: "userInputChat",
             data: {
                 message: message,
             } as UserInputChatEvent,
-        });
+        }, exceptOrigin);
     }
 
     sendEnterEvent(name: string) {
@@ -521,8 +525,11 @@ class IframeListener {
     /**
      * Sends the message... to all allowed iframes.
      */
-    public postMessage(message: IframeResponseEvent<keyof IframeResponseEventMap>) {
+    public postMessage(message: IframeResponseEvent<keyof IframeResponseEventMap>, exceptOrigin?: Window) {
         for (const iframe of this.iframes) {
+            if (exceptOrigin === iframe.contentWindow) {
+                continue;
+            }
             iframe.contentWindow?.postMessage(message, "*");
         }
     }
diff --git a/front/src/Api/ScriptUtils.ts b/front/src/Api/ScriptUtils.ts
index f0a0625a..d6d70e81 100644
--- a/front/src/Api/ScriptUtils.ts
+++ b/front/src/Api/ScriptUtils.ts
@@ -11,9 +11,9 @@ class ScriptUtils {
         window.location.href = url;
     }
 
-    public sendAnonymousChat(chatEvent: ChatEvent) {
+    public sendAnonymousChat(chatEvent: ChatEvent, origin?: Window) {
         const userId = playersStore.addFacticePlayer(chatEvent.author);
-        chatMessagesStore.addExternalMessage(userId, chatEvent.message);
+        chatMessagesStore.addExternalMessage(userId, chatEvent.message, origin);
     }
 }
 
diff --git a/front/src/Stores/ChatStore.ts b/front/src/Stores/ChatStore.ts
index b8d4ea7b..9dfe7e42 100644
--- a/front/src/Stores/ChatStore.ts
+++ b/front/src/Stores/ChatStore.ts
@@ -87,7 +87,10 @@ function createChatMessagesStore() {
                 return list;
             });
         },
-        addExternalMessage(authorId: number, text: string) {
+        /**
+         * @param origin The iframe that originated this message (if triggered from the Scripting API), or undefined otherwise.
+         */
+        addExternalMessage(authorId: number, text: string, origin?: Window) {
             update((list) => {
                 const lastMessage = list[list.length - 1];
                 if (
@@ -106,7 +109,7 @@ function createChatMessagesStore() {
                     });
                 }
 
-                iframeListener.sendUserInputChat(text);
+                iframeListener.sendUserInputChat(text, origin);
                 return list;
             });
             chatVisibilityStore.set(true);