UX: remove last reply from My Threads preview + restyle (#25568)

On mobile, when viewing the My Threads area, each thread will show:

- The avatar of the last responder in the thread, overlaid with the chat thread symbol to visually distinguish this area from DMs.
- Either the thread title, where applicable, or the first message of the thread, truncated to fit on one line.
- The channel where the thread originated.
- The last message sent in the thread, truncated to fit on one line.
- When the last message was sent in the thread.

---------

Co-authored-by: David Battersby <info@davidbattersby.com>

plugins/chat/assets/javascripts/discourse/components/channel-icon/index.gjs

@@ -19,6 +19,10 @@ export default class ChatChannelIcon extends Component {
     return htmlSafe(`color: #${this.args.channel.chatable.color}`);
   }
 
+  get isThreadsList() {
+    return this.args.thread ?? false;
+  }
+
   <template>
     {{#if @channel.isDirectMessageChannel}}
       <div class="chat-channel-icon">
@@ -44,6 +48,19 @@ export default class ChatChannelIcon extends Component {
           {{/if}}
         </span>
       </div>
+    {{else if this.isThreadsList}}
+      <div class="chat-channel-icon">
+        <div class="chat-channel-icon --avatar">
+          <ChatUserAvatar
+            @user={{@thread.originalMessage.user}}
+            @interactive={{true}}
+            @showPresence={{false}}
+          />
+          <div class="avatar-flair --threads">
+            {{icon "discourse-threads"}}
+          </div>
+        </div>
+      </div>
     {{/if}}
   </template>
 }

plugins/chat/assets/javascripts/discourse/components/chat/thread/header.gjs

@@ -24,14 +24,14 @@ export default class ChatThreadHeader extends Component {
       route = "chat.channel.threads";
       title = I18n.t("chat.return_to_threads_list");
       models = this.channel?.routeModels;
-    } else if (!this.currentUser.isInDoNotDisturb() && this.unreadCount > 0) {
-      route = "chat.channel.threads";
-      title = I18n.t("chat.return_to_threads_list");
-      models = this.channel?.routeModels;
     } else if (prevPage === "chat.threads") {
       route = "chat.threads";
       title = I18n.t("chat.my_threads.title");
       models = [];
+    } else if (!this.currentUser.isInDoNotDisturb() && this.unreadCount > 0) {
+      route = "chat.channel.threads";
+      title = I18n.t("chat.return_to_threads_list");
+      models = this.channel?.routeModels;
     } else {
       route = "chat.channel.index";
       title = I18n.t("chat.return_to_channel");
@@ -53,6 +53,12 @@ export default class ChatThreadHeader extends Component {
     return this.channel?.threadsManager?.unreadThreadCount;
   }
 
+  get showThreadUnreadIndicator() {
+    return (
+      this.backLink.route === "chat.channel.threads" && this.unreadCount > 0
+    );
+  }
+
   <template>
     <Navbar @showFullTitle={{@showFullTitle}} as |navbar|>
       {{#if (and this.channel.threadingEnabled @thread)}}
@@ -61,7 +67,9 @@ export default class ChatThreadHeader extends Component {
           @routeModels={{this.backLink.models}}
           @title={{this.backLink.title}}
         >
+          {{#if this.showThreadUnreadIndicator}}
             <ChatThreadHeaderUnreadIndicator @channel={{this.channel}} />
+          {{/if}}
           {{icon "chevron-left"}}
         </navbar.BackButton>
       {{/if}}

plugins/chat/assets/javascripts/discourse/components/user-threads/index.gjs

@@ -3,15 +3,18 @@ import { cached } from "@glimmer/tracking";
 import { service } from "@ember/service";
 import i18n from "discourse-common/helpers/i18n";
 import { bind } from "discourse-common/utils/decorators";
+import ChannelIcon from "discourse/plugins/chat/discourse/components/channel-icon";
 import ChannelTitle from "discourse/plugins/chat/discourse/components/channel-title";
 import List from "discourse/plugins/chat/discourse/components/chat/list";
 import ThreadIndicator from "discourse/plugins/chat/discourse/components/chat-message-thread-indicator";
 import ThreadTitle from "discourse/plugins/chat/discourse/components/thread-title";
+import ThreadPreview from "discourse/plugins/chat/discourse/components/user-threads/preview";
 
 export default class UserThreads extends Component {
   @service chat;
   @service chatApi;
   @service chatChannelsManager;
+  @service site;
 
   @cached
   get threadsCollection() {
@@ -41,14 +44,23 @@ export default class UserThreads extends Component {
     >
       <list.Item as |thread|>
         <div class="c-user-thread" data-id={{thread.id}}>
-          <ThreadTitle @thread={{thread}} />
+          {{#if this.site.mobileView}}
+            <ChannelIcon @thread={{thread}} />
+          {{/if}}
+
           <ChannelTitle @channel={{thread.channel}} />
+          <ThreadTitle @thread={{thread}} />
+
+          {{#if this.site.mobileView}}
+            <ThreadPreview @preview={{thread.preview}} />
+          {{else}}
             <ThreadIndicator
               @message={{thread.originalMessage}}
               @interactiveUser={{false}}
               @interactiveThread={{false}}
               tabindex="-1"
             />
+          {{/if}}
         </div>
       </list.Item>
       <list.EmptyState>

plugins/chat/assets/javascripts/discourse/components/user-threads/preview.gjs

@@ -0,0 +1,23 @@
+import Component from "@glimmer/component";
+import formatDate from "discourse/helpers/format-date";
+
+export default class ThreadPreview extends Component {
+  get lastReplyDate() {
+    return formatDate(this.args.preview.lastReplyCreatedAt, { leaveAgo: true });
+  }
+
+  <template>
+    <span class="chat-message-thread-indicator__last-reply-timestamp">
+      {{this.lastReplyDate}}
+    </span>
+    <div class="c-user-thread__excerpt">
+      <div class="c-user-thread__excerpt-poster">
+        {{@preview.lastReplyUser.username}}
+      </div>
+      <span>:</span>
+      <span class="c-user-thread__excerpt-text">
+        {{@preview.lastReplyExcerpt}}
+      </span>
+    </div>
+  </template>
+}

plugins/chat/assets/stylesheets/mobile/chat-user-threads.scss

@@ -1,9 +1,67 @@
-.chat-user-threads {
-  .chat__thread-title {
-    justify-content: space-between;
+.c-user-thread {
+  display: grid;
+  grid-template-areas:
+    "avatar category timestamp"
+    "avatar title indicator"
+    "avatar excerpt excerpt";
+  grid-template-columns: auto 1fr auto;
+  grid-column-gap: 0.75em;
+  margin-inline: 0;
+  padding: 0.5rem 1.5rem;
+
+  .chat-channel-icon {
+    grid-area: avatar;
+    position: relative;
+
+    .avatar {
+      margin-top: 4px;
+      width: var(--channel-list-avatar-size);
+      height: var(--channel-list-avatar-size);
     }
   }
 
-.c-user-thread {
-  margin-inline: 1.5rem;
+  .avatar-flair.--threads {
+    position: absolute;
+    top: -4px;
+    right: -3px;
+    background: var(--primary-low);
+    border-radius: 50%;
+    padding: 0.2em;
+    line-height: var(--line-height-small);
+    border: 2px solid var(--secondary-very-high);
+    color: var(--primary-high);
+  }
+
+  .chat__thread-title-container {
+    @include ellipsis;
+    grid-area: title;
+    .chat__thread-title {
+      &__name {
+        @include ellipsis;
+      }
+    }
+  }
+
+  .chat-channel-title {
+    grid-area: category;
+  }
+
+  .chat-message-thread-indicator__last-reply-timestamp {
+    grid-area: timestamp;
+    font-size: var(--font-down-2-rem);
+    align-self: center;
+  }
+
+  .c-user-thread__excerpt {
+    @include ellipsis;
+    grid-area: excerpt;
+    display: flex;
+    color: var(--primary-high);
+  }
+
+  .c-user-thread__excerpt-text {
+    margin-left: 0.25em;
+    overflow: hidden;
+    text-overflow: ellipsis;
+  }
 }

plugins/chat/spec/system/user_threads_spec.rb

@@ -244,4 +244,22 @@ RSpec.describe "User threads", type: :system do
       expect(user_threads_page).to have_threads
     end
   end
+
+  context "when in mobile", mobile: true do
+    before do
+      chat_thread_chain_bootstrap(channel: channel_1, users: [current_user, Fabricate(:user)])
+    end
+
+    it "has the expected UI elements" do
+      chat_page.visit_user_threads
+
+      expect(user_threads_page).to have_threads(count: 1)
+      expect(user_threads_page).to have_css(".chat-user-avatar")
+      expect(user_threads_page).to have_css(".chat__thread-title__name")
+      expect(user_threads_page).to have_css(".chat-channel-name")
+      expect(user_threads_page).to have_css(".c-user-thread__excerpt")
+      expect(user_threads_page).to have_css(".c-user-thread__excerpt-poster")
+      expect(user_threads_page).to have_css(".c-user-thread .relative-date")
+    end
+  end
 end