FEATURE: Allow selective dismissal of new and unread topics (#12976)

This PR improves the UI of bulk select so that its context is applied to the Dismiss Unread and Dismiss New buttons. Regular users (not just staff) are now able to use topic bulk selection on the /new and /unread routes to perform these dismiss actions more selectively.

For Dismiss Unread, there is a new count in the text of the button and in the modal when one or more topic is selected with the bulk select checkboxes.

For Dismiss New, there is a count in the button text, and we have added functionality to the server side to accept an array of topic ids to dismiss new for, instead of always having to dismiss all new, the same as the bulk dismiss unread functionality. To clean things up, the `DismissTopics` service has been rolled into the `TopicsBulkAction` service.

We now also show the top Dismiss/Dismiss New button based on whether the bottom one is in the viewport, not just based on the topic count.

spec/requests/topics_controller_spec.rb

@@ -2801,6 +2801,17 @@ RSpec.describe TopicsController do
         }
       end
 
+      it "raises an error if topic_ids is provided and it is not an array" do
+        put "/topics/bulk.json", params: {
+          topic_ids: "1", operation: operation
+        }
+        expect(response.parsed_body["errors"].first).to match(/Expecting topic_ids to contain a list/)
+        put "/topics/bulk.json", params: {
+          topic_ids: [1], operation: operation
+        }
+        expect(response.parsed_body["errors"]).to eq(nil)
+      end
+
       it "respects the tracked parameter" do
         # untracked topic
         CategoryUser.set_notification_level_for_category(user,
@@ -2975,7 +2986,7 @@ RSpec.describe TopicsController do
       it 'dismisses topics for main category and subcategories' do
         sign_in(user)
 
-        TopicTrackingState.expects(:publish_dismiss_new).with(user.id, topic_ids: [subcategory_topic.id, category_topic.id])
+        TopicTrackingState.expects(:publish_dismiss_new).with(user.id, topic_ids: [category_topic.id, subcategory_topic.id])
 
         put "/topics/reset-new.json?category_id=#{category.id}&include_subcategories=true"
 
@@ -3011,6 +3022,69 @@ RSpec.describe TopicsController do
         expect(DismissedTopicUser.where(user_id: user.id).pluck(:topic_id)).to eq([tag_and_category_topic.id])
       end
     end
+
+    context "specific topics" do
+      fab!(:topic2) { Fabricate(:topic) }
+      fab!(:topic3) { Fabricate(:topic) }
+
+      it "updates the `new_since` date" do
+        sign_in(user)
+
+        old_date = 2.years.ago
+        user.user_stat.update_column(:new_since, old_date)
+        user.update_column(:created_at, old_date)
+
+        TopicTrackingState.expects(:publish_dismiss_new).with(user.id, topic_ids: [topic2.id, topic3.id]).at_least_once
+
+        put "/topics/reset-new.json", { params: { topic_ids: [topic2.id, topic3.id] } }
+        expect(response.status).to eq(200)
+        user.reload
+        expect(user.user_stat.new_since.to_date).not_to eq(old_date.to_date)
+        expect(DismissedTopicUser.where(user_id: user.id).pluck(:topic_id)).to match_array([topic2.id, topic3.id])
+      end
+
+      it "raises an error if topic_ids is provided and it is not an array" do
+        sign_in(user)
+        put "/topics/reset-new.json", params: { topic_ids: topic2.id }
+        expect(response.parsed_body["errors"].first).to match(/Expecting topic_ids to contain a list/)
+        put "/topics/reset-new.json", params: { topic_ids: [topic2.id] }
+        expect(response.parsed_body["errors"]).to eq(nil)
+      end
+
+      describe "when tracked param is true" do
+        it "does not update user_stat.new_since and does not dismiss untracked topics" do
+          sign_in(user)
+
+          old_date = 2.years.ago
+          user.user_stat.update_column(:new_since, old_date)
+
+          put "/topics/reset-new.json?tracked=true", { params: { topic_ids: [topic2.id, topic3.id] } }
+          expect(response.status).to eq(200)
+          user.reload
+          expect(user.user_stat.new_since.to_date).to eq(old_date.to_date)
+          expect(DismissedTopicUser.where(user_id: user.id).pluck(:topic_id)).to be_empty
+        end
+
+        it "creates topic user records for each unread topic" do
+          sign_in(user)
+          user.user_stat.update_column(:new_since, 2.years.ago)
+
+          tracked_category = Fabricate(:category)
+          CategoryUser.set_notification_level_for_category(user,
+                                                           NotificationLevels.all[:tracking],
+                                                           tracked_category.id)
+          tracked_topic = create_post.topic
+          tracked_topic.update!(category_id: tracked_category.id)
+          topic2.update!(category_id: tracked_category.id)
+
+          create_post # This is a new post, but is not tracked so a record will not be created for it
+          expect do
+            put "/topics/reset-new.json?tracked=true", { params: { topic_ids: [tracked_topic.id, topic2.id, topic3.id] } }
+          end.to change { DismissedTopicUser.where(user_id: user.id).count }.by(2)
+          expect(DismissedTopicUser.where(user_id: user.id).pluck(:topic_id)).to match_array([tracked_topic.id, topic2.id])
+        end
+      end
+    end
   end
 
   describe '#feature_stats' do