FIX: Keep track of suggestion updates during scrolling and navigation. (#23190)

This PR changes how we track which lists are available for a topic and how we decide which is the active one. The new approach centralizes everything in the service, and exposes functions for adding/removing a list, which each calls via `did-insert/will-destroy` modifiers.

It makes it much easier to track and update state when navigated to another topic or PM, ensuring things get updated correctly.

app/assets/javascripts/discourse/app/components/more-topics.hbs

@@ -1,14 +1,15 @@
-<div class="more-topics__container" {{did-insert this.buildListPills}}>
+<div class="more-topics__container">
   {{#unless this.singleList}}
     <div class="row">
       <ul class="nav nav-pills">
-        {{#each this.availablePills as |pill|}}
+        {{#each this.availableTabs as |tab|}}
           <li>
             <DButton
-              @translatedTitle={{pill.name}}
-              @translatedLabel={{pill.name}}
-              @class={{if pill.selected "active"}}
-              @action={{action "rememberTopicListPreference" pill.id}}
+              @translatedTitle={{tab.name}}
+              @translatedLabel={{tab.name}}
+              @class={{if (eq tab.id this.selectedTab) "active"}}
+              @action={{action "rememberTopicListPreference" tab.id}}
+              @icon={{tab.icon}}
             />
           </li>
         {{/each}}

app/assets/javascripts/discourse/app/components/more-topics.js

@@ -1,8 +1,6 @@
 import Component from "@glimmer/component";
 import { inject as service } from "@ember/service";
-import { next } from "@ember/runloop";
 import { action, computed } from "@ember/object";
-import { tracked } from "@glimmer/tracking";
 import I18n from "I18n";
 import { categoryBadgeHTML } from "discourse/helpers/category-link";
 import getURL from "discourse-common/lib/get-url";
@@ -15,59 +13,24 @@ export default class MoreTopics extends Component {
   @service topicTrackingState;
   @service currentUser;
 
-  @tracked availablePills = [];
-  @tracked singleList = false;
-
   @action
   rememberTopicListPreference(value) {
-    // Don't change the preference when selecting related PMs.
-    // It messes with the topics pref.
-    const rememberPref = value !== "related-messages";
-
-    this.moreTopicsPreferenceTracking.updatePreference(value, rememberPref);
-
-    this.buildListPills();
+    this.moreTopicsPreferenceTracking.updatePreference(value);
   }
 
-  @action
-  buildListPills() {
-    next(() => {
-      const pills = Array.from(
-        document.querySelectorAll(".more-topics__list")
-      ).map((topicList) => {
-        return {
-          name: topicList.dataset.mobileTitle,
-          id: topicList.dataset.listId,
-        };
-      });
+  @computed("moreTopicsPreferenceTracking.topicLists")
+  get singleList() {
+    return this.availableTabs.length === 1;
+  }
 
-      if (pills.length === 0) {
-        return;
-      } else if (pills.length === 1) {
-        this.singleList = true;
-      }
+  @computed("moreTopicsPreferenceTracking.selectedTab")
+  get selectedTab() {
+    return this.moreTopicsPreferenceTracking.selectedTab;
+  }
 
-      let preference = this.moreTopicsPreferenceTracking.preference;
-      // Scenario where we have a preference, but there
-      // are no more elements in it.
-      const listPresent = pills.find((pill) => pill.id === preference);
-
-      if (!listPresent) {
-        const rememberPref = false;
-
-        this.moreTopicsPreferenceTracking.updatePreference(
-          pills[0].id,
-          rememberPref
-        );
-        preference = pills[0].id;
-      }
-
-      pills.forEach((pill) => {
-        pill.selected = pill.id === preference;
-      });
-
-      this.availablePills = pills;
-    });
+  @computed("moreTopicsPreferenceTracking.topicLists")
+  get availableTabs() {
+    return this.moreTopicsPreferenceTracking.topicLists;
   }
 
   @computed(

app/assets/javascripts/discourse/app/components/related-messages.hbs

@@ -3,8 +3,8 @@
   class="more-topics__list {{if this.hidden 'hidden'}}"
   role="complementary"
   aria-labelledby="related-messages-title"
-  data-mobile-title={{i18n "related_messages.pill"}}
-  data-list-id={{this.listId}}
+  {{did-insert this.registerList}}
+  {{will-destroy this.removeList}}
 >
   <h3 id="related-messages-title" class="more-topics__list-title">
     {{i18n "related_messages.title"}}

app/assets/javascripts/discourse/app/components/related-messages.js

@@ -1,7 +1,8 @@
 import Component from "@glimmer/component";
-import { computed } from "@ember/object";
+import { action, computed } from "@ember/object";
 import getURL from "discourse-common/lib/get-url";
 import { inject as service } from "@ember/service";
+import I18n from "I18n";
 
 export default class RelatedMessages extends Component {
   @service moreTopicsPreferenceTracking;
@@ -9,9 +10,22 @@ export default class RelatedMessages extends Component {
 
   listId = "related-Messages";
 
-  @computed("moreTopicsPreferenceTracking.preference")
+  @computed("moreTopicsPreferenceTracking.selectedTab")
   get hidden() {
-    return this.moreTopicsPreferenceTracking.preference !== this.listId;
+    return this.moreTopicsPreferenceTracking.selectedTab !== this.listId;
+  }
+
+  @action
+  registerList() {
+    this.moreTopicsPreferenceTracking.registerTopicList({
+      name: I18n.t("related_messages.pill"),
+      id: this.listId,
+    });
+  }
+
+  @action
+  removeList() {
+    this.moreTopicsPreferenceTracking.removeTopicList(this.listId);
   }
 
   get targetUser() {

app/assets/javascripts/discourse/app/components/suggested-topics.hbs

@@ -3,8 +3,8 @@
   class="more-topics__list {{if this.hidden 'hidden'}}"
   role="complementary"
   aria-labelledby="suggested-topics-title"
-  data-mobile-title={{i18n "suggested_topics.pill"}}
-  data-list-id={{this.listId}}
+  {{did-insert this.registerList}}
+  {{will-destroy this.removeList}}
 >
   <UserTip @id="suggested_topics" @selector=".user-tip-reference" />
 

app/assets/javascripts/discourse/app/components/suggested-topics.js

@@ -1,6 +1,7 @@
 import Component from "@glimmer/component";
-import { computed } from "@ember/object";
+import { action, computed } from "@ember/object";
 import { inject as service } from "@ember/service";
+import I18n from "I18n";
 
 export default class SuggestedTopics extends Component {
   @service moreTopicsPreferenceTracking;
@@ -17,8 +18,21 @@ export default class SuggestedTopics extends Component {
     }
   }
 
-  @computed("moreTopicsPreferenceTracking.preference")
+  @computed("moreTopicsPreferenceTracking.selectedTab")
   get hidden() {
-    return this.moreTopicsPreferenceTracking.preference !== this.listId;
+    return this.moreTopicsPreferenceTracking.selectedTab !== this.listId;
+  }
+
+  @action
+  registerList() {
+    this.moreTopicsPreferenceTracking.registerTopicList({
+      name: I18n.t("suggested_topics.pill"),
+      id: this.listId,
+    });
+  }
+
+  @action
+  removeList() {
+    this.moreTopicsPreferenceTracking.removeTopicList(this.listId);
   }
 }

app/assets/javascripts/discourse/app/services/more-topics-preference-tracking.js

@@ -6,18 +6,49 @@ const TOPIC_LIST_PREFERENCE_KEY = "more-topics-list-preference";
 export default class MoreTopicsPreferenceTracking extends Service {
   @service keyValueStore;
 
-  @tracked preference;
+  @tracked selectedTab = null;
+  @tracked topicLists = [];
+
+  memoryTab = null;
 
   init() {
     super.init(...arguments);
-    this.preference = this.keyValueStore.get(TOPIC_LIST_PREFERENCE_KEY);
+    this.memoryTab = this.keyValueStore.get(TOPIC_LIST_PREFERENCE_KEY);
   }
 
-  updatePreference(value, rememberPref = true) {
+  updatePreference(value) {
+    // Don't change the preference when selecting related PMs.
+    // It messes with the topics pref.
+    const rememberPref = value !== "related-messages";
+
     if (rememberPref) {
       this.keyValueStore.set({ key: TOPIC_LIST_PREFERENCE_KEY, value });
+      this.memoryTab = value;
     }
 
-    this.preference = value;
+    this.selectedTab = value;
+  }
+
+  registerTopicList(item) {
+    // We have a preference stored and the list exists.
+    if (this.memoryTab && this.memoryTab === item.id) {
+      this.selectedTab = item.id;
+    }
+
+    // Use the first list as a default. Future lists may override this
+    // if they match the stored preference.
+    if (!this.selectedTab) {
+      this.selectedTab = item.id;
+    }
+
+    this.topicLists = [...this.topicLists, item];
+  }
+
+  removeTopicList(itemId) {
+    this.topicLists = this.topicLists.filter((item) => item.id !== itemId);
+
+    if (this.selectedTab === itemId) {
+      this.selectedTab = this.topicLists[0]?.id;
+    }
   }
 }

app/assets/stylesheets/common/components/more-topics.scss

@@ -9,6 +9,10 @@
       .btn {
         padding: 0.5em 0.65em;
       }
+
+      .btn.active .d-icon {
+        color: var(--primary-low);
+      }
     }
   }