DEV: Remove jQuery animate calls (#15321)

Affects j/k navigation and PM interaction with @discobot.

app/assets/javascripts/discourse/app/controllers/topic.js

@@ -19,10 +19,8 @@ import bootbox from "bootbox";
 import { bufferedProperty } from "discourse/mixins/buffered-content";
 import { buildQuote } from "discourse/lib/quote";
 import { deepMerge } from "discourse-common/lib/object";
-import discourseDebounce from "discourse-common/lib/debounce";
 import { escapeExpression } from "discourse/lib/utilities";
 import { extractLinkMeta } from "discourse/lib/render-topic-featured-link";
-import isElementInViewport from "discourse/lib/is-element-in-viewport";
 import { popupAjaxError } from "discourse/lib/ajax-error";
 import { inject as service } from "@ember/service";
 import showModal from "discourse/lib/show-modal";
@@ -1679,52 +1677,11 @@ export default Controller.extend(bufferedProperty("model"), {
             }
           }
         }
-
-        // scroll to bottom is very specific to new posts from discobot
-        // hence the -2 check (discobot id). We can shift all this code
-        // to discobot plugin longer term
-        if (
-          topic.get("isPrivateMessage") &&
-          this.currentUser &&
-          this.currentUser.get("id") !== data.user_id &&
-          data.user_id === -2 &&
-          data.type === "created"
-        ) {
-          const postNumber = data.post_number;
-          const notInPostStream =
-            topic.get("highest_post_number") <= postNumber;
-          const postNumberDifference = postNumber - topic.get("currentPost");
-
-          if (
-            notInPostStream &&
-            postNumberDifference > 0 &&
-            postNumberDifference < 7
-          ) {
-            this._scrollToPost(data.post_number);
-          }
-        }
       },
       this.get("model.message_bus_last_id")
     );
   },
 
-  _scrollToPost(postNumber) {
-    discourseDebounce(
-      this,
-      function () {
-        const $post = $(`.topic-post article#post_${postNumber}`);
-
-        if ($post.length === 0 || isElementInViewport($post[0])) {
-          return;
-        }
-
-        $("html, body").animate({ scrollTop: $post.offset().top }, 1000);
-      },
-      postNumber,
-      500
-    );
-  },
-
   unsubscribe() {
     // never unsubscribe when navigating from topic to topic
     if (!this.get("model.id")) {

app/assets/javascripts/discourse/app/lib/keyboard-shortcuts.js

@@ -708,10 +708,11 @@ export default {
     }
   },
 
-  _scrollTo(scrollTop, complete) {
-    $("html, body")
-      .stop(true, true)
-      .animate({ scrollTop }, { duration: animationDuration, complete });
+  _scrollTo(scrollTop) {
+    window.scrollTo({
+      top: scrollTop,
+      behavior: "smooth",
+    });
   },
 
   _scrollList($article) {
@@ -738,13 +739,7 @@ export default {
       scrollPos = 0;
     }
 
-    if (this._scrollAnimation) {
-      this._scrollAnimation.stop();
-    }
-    this._scrollAnimation = $("html, body").animate(
-      { scrollTop: scrollPos + "px" },
-      animationDuration
-    );
+    this._scrollTo(scrollPos);
   },
 
   categoriesTopicsList() {

plugins/discourse-narrative-bot/assets/javascripts/initializers/new-user-narrative.js

@@ -1,4 +1,6 @@
 import { ajax } from "discourse/lib/ajax";
+import discourseDebounce from "discourse-common/lib/debounce";
+import isElementInViewport from "discourse/lib/is-element-in-viewport";
 import { withPluginApi } from "discourse/lib/plugin-api";
 
 const PLUGIN_ID = "new-user-narrative";
@@ -39,6 +41,68 @@ function initialize(api) {
       }
       return this._super(bookmark, post);
     },
+
+    subscribe() {
+      this._super(...arguments);
+
+      this.messageBus.subscribe(`/topic/${this.get("model.id")}`, (data) => {
+        const topic = this.model;
+
+        // scroll only for discobot (-2 is discobot id)
+        if (
+          topic.get("isPrivateMessage") &&
+          this.currentUser &&
+          this.currentUser.get("id") !== data.user_id &&
+          data.user_id === -2 &&
+          data.type === "created"
+        ) {
+          const postNumber = data.post_number;
+          const notInPostStream =
+            topic.get("highest_post_number") <= postNumber;
+          const postNumberDifference = postNumber - topic.get("currentPost");
+
+          if (
+            notInPostStream &&
+            postNumberDifference > 0 &&
+            postNumberDifference < 7
+          ) {
+            this._scrollToDiscobotPost(data.post_number);
+          }
+        }
+      });
+      // No need to unsubscribe, core unsubscribes /topic/* routes
+    },
+
+    _scrollToDiscobotPost(postNumber) {
+      discourseDebounce(
+        this,
+        function () {
+          const post = document.querySelector(
+            `.topic-post article#post_${postNumber}`
+          );
+
+          if (!post || isElementInViewport(post)) {
+            return;
+          }
+
+          const headerOffset =
+            parseInt(
+              getComputedStyle(document.body).getPropertyValue(
+                "--header-offset"
+              ),
+              10
+            ) || 0;
+          const viewportOffset = post.getBoundingClientRect();
+
+          window.scrollTo({
+            top: window.scrollY + viewportOffset.top - headerOffset,
+            behavior: "smooth",
+          });
+        },
+        postNumber,
+        500
+      );
+    },
   });
 
   api.attachWidgetAction("header", "headerSearchContextTrigger", function () {