FIX: loading extension after chat popout and url change

WIP: Transforming to TypeScript

src/TwitchNote.ts

@@ -0,0 +1,49 @@
+export default class TwitchNote {
+
+    observer: MutationObserver | null = null;
+    chatContainerNode?: Element;
+
+    constructor() {
+    }
+
+    init(chatContainerNode: Element) {
+        this.chatContainerNode = chatContainerNode;
+        console.log('CHAT CONTAINER INITIATED');
+        this.startObserver(chatContainerNode);
+        // add Notes management button
+        this.addNotesButton();
+    }
+
+    startObserver(targetNode: Element) {
+        // discard old observer
+        if (this.observer) {
+            this.observer.disconnect();
+        }
+
+        const observerCallback = (mutationList: MutationRecord[]) => {
+            // preventing multiple chat updates at once in case update process
+            // is taking longer or chat is super active
+            if (!changeInProgress) {
+                for (const mutation of mutationList) {
+                    if (mutation.type === "childList") {
+                        changeInProgress = true;
+                        // add badges next to users
+                        this.addUserNoteBadges();
+                        changeInProgress = false;
+                    }
+                }
+            }
+        };
+
+        let changeInProgress = false;
+        const observerConfig = {attributes: true, childList: true, subtree: true};
+        this.observer = new MutationObserver(observerCallback);
+        this.observer.observe(targetNode, observerConfig);
+    }
+
+    addNotesButton() {
+    }
+
+    addUserNoteBadges() {
+    }
+}