DEV: Improve title suggester suggestions when editing topic

app/controllers/discourse_ai/ai_helper/assistant_controller.rb

@@ -53,19 +53,32 @@ def suggest
       end
 
       def suggest_title
-        input = get_text_param!
+        assistant = DiscourseAi::AiHelper::Assistant.new
+
+        if params[:topic_id]
+          topic = Topic.find_by(id: params[:topic_id])
+
+          topic_content =
+            topic
+              .posts
+              .joins(:user)
+              .pluck(:post_number, :raw, :username, :last_version_at)
+              .map do |pn, raw_text, username, last_version_at|
+                { poster: username, id: pn, text: raw_text, last_version_at: last_version_at }
+              end
+
+          truncated_content = topic_content.map { |item| assistant.truncate(item) }
+
+          input = truncated_content
+        else
+          input = get_text_param!
+        end
 
         prompt = CompletionPrompt.enabled_by_name("generate_titles")
         raise Discourse::InvalidParameters.new(:mode) if !prompt
 
         hijack do
-          render json:
-                   DiscourseAi::AiHelper::Assistant.new.generate_and_send_prompt(
-                     prompt,
-                     input,
-                     current_user,
-                   ),
-                 status: 200
+          render json: assistant.generate_and_send_prompt(prompt, input, current_user), status: 200
         end
       rescue DiscourseAi::Completions::Endpoints::Base::CompletionFailed
         render_json_error I18n.t("discourse_ai.ai_helper.errors.completion_request_failed"),

assets/javascripts/discourse/components/suggestion-menus/ai-title-suggester.gjs

@@ -17,30 +17,15 @@ export default class AiTitleSuggester extends Component {
   @tracked untriggers = [];
   @tracked triggerIcon = "discourse-sparkles";
   @tracked content = null;
-  @tracked topicContent = null;
-
-  constructor() {
-    super(...arguments);
-
-    if (!this.topicContent && this.args.composer?.reply === undefined) {
-      this.fetchTopicContent();
-    }
-  }
-
-  async fetchTopicContent() {
-    await ajax(`/t/${this.args.buffered.content.id}.json`).then(
-      ({ post_stream }) => {
-        this.topicContent = post_stream.posts[0].cooked;
-      }
-    );
-  }
 
   get showSuggestionButton() {
     const composerFields = document.querySelector(".composer-fields");
     const editTopicTitleField = document.querySelector(".edit-topic-title");
 
-    this.content = this.args.composer?.reply || this.topicContent;
-    const showTrigger = this.content?.length > MIN_CHARACTER_COUNT;
+    this.content = this.args.composer?.reply;
+    const showTrigger =
+      this.content?.length > MIN_CHARACTER_COUNT ||
+      this.args.topicState === "edit";
 
     if (composerFields) {
       if (showTrigger) {
@@ -69,13 +54,20 @@ export default class AiTitleSuggester extends Component {
 
     this.loading = true;
     this.triggerIcon = "spinner";
+    const data = {};
+
+    if (this.content) {
+      data.text = this.content;
+    } else {
+      data.topic_id = this.args.buffered.content.id;
+    }
 
     try {
       const { suggestions } = await ajax(
         "/discourse-ai/ai-helper/suggest_title",
         {
           method: "POST",
-          data: { text: this.content },
+          data,
         }
       );
       this.suggestions = suggestions;

assets/javascripts/discourse/connectors/after-composer-title-input/ai-title-suggestion.gjs

@@ -13,6 +13,6 @@ export default class AiTitleSuggestion extends Component {
   }
 
   <template>
-    <AiTitleSuggester @composer={{@outletArgs.composer}} />
+    <AiTitleSuggester @composer={{@outletArgs.composer}} @topicState="new" />
   </template>
 }

assets/javascripts/discourse/connectors/edit-topic-title__after/ai-title-suggestion.gjs

@@ -13,6 +13,6 @@ export default class AiTitleSuggestion extends Component {
   }
 
   <template>
-    <AiTitleSuggester @buffered={{@outletArgs.buffered}} />
+    <AiTitleSuggester @buffered={{@outletArgs.buffered}} @topicState="edit" />
   </template>
 }

lib/ai_helper/assistant.rb

@@ -206,6 +206,22 @@ def generate_image_caption(upload, user)
         raw_caption.delete("|").squish.truncate_words(IMAGE_CAPTION_MAX_WORDS)
       end
 
+      def truncate(item)
+        item_content = item[:text].to_s
+        split_1, split_2 =
+          [item_content[0, item_content.size / 2], item_content[(item_content.size / 2)..-1]]
+
+        truncation_length = 500
+        tokenizer = helper_llm.llm_model.tokenizer_class
+
+        item[:text] = [
+          tokenizer.truncate(split_1, truncation_length),
+          tokenizer.truncate(split_2.reverse, truncation_length).reverse,
+        ].join(" ")
+
+        item
+      end
+
       private
 
       SANITIZE_REGEX_STR =

spec/requests/ai_helper/assistant_controller_spec.rb

@@ -134,6 +134,70 @@
     end
   end
 
+  describe "#suggest_title" do
+    fab!(:topic)
+    fab!(:post_1) { Fabricate(:post, topic: topic, raw: "I love apples") }
+    fab!(:post_3) { Fabricate(:post, topic: topic, raw: "I love mangos") }
+    fab!(:post_2) { Fabricate(:post, topic: topic, raw: "I love bananas") }
+
+    context "when logged in as an allowed user" do
+      fab!(:user)
+
+      before do
+        sign_in(user)
+        user.group_ids = [Group::AUTO_GROUPS[:trust_level_1]]
+        SiteSetting.composer_ai_helper_allowed_groups = Group::AUTO_GROUPS[:trust_level_1]
+      end
+
+      context "when suggesting titles with a topic_id" do
+        let(:title_suggestions) do
+          "<item>What are your favourite fruits?</item><item>Love for fruits</item><item>Fruits are amazing</item><item>Favourite fruit list</item><item>Fruit share topic</item>"
+        end
+        let(:title_suggestions_array) do
+          [
+            "What are your favourite fruits?",
+            "Love for fruits",
+            "Fruits are amazing",
+            "Favourite fruit list",
+            "Fruit share topic",
+          ]
+        end
+
+        it "returns title suggestions based on all topic post context" do
+          DiscourseAi::Completions::Llm.with_prepared_responses([title_suggestions]) do
+            post "/discourse-ai/ai-helper/suggest_title", params: { topic_id: topic.id }
+
+            expect(response.status).to eq(200)
+            expect(response.parsed_body["suggestions"]).to eq(title_suggestions_array)
+          end
+        end
+      end
+
+      context "when suggesting titles with input text" do
+        let(:title_suggestions) do
+          "<item>Apples - the best fruit</item><item>Why apples are great</item><item>Apples are the best fruit</item><item>My love for apples</item><item>I love apples</item>"
+        end
+        let(:title_suggestions_array) do
+          [
+            "Apples - the best fruit",
+            "Why apples are great",
+            "Apples are the best fruit",
+            "My love for apples",
+            "I love apples",
+          ]
+        end
+        it "returns title suggestions based on the input text" do
+          DiscourseAi::Completions::Llm.with_prepared_responses([title_suggestions]) do
+            post "/discourse-ai/ai-helper/suggest_title", params: { text: post_1.raw }
+
+            expect(response.status).to eq(200)
+            expect(response.parsed_body["suggestions"]).to eq(title_suggestions_array)
+          end
+        end
+      end
+    end
+  end
+
   describe "#caption_image" do
     let(:image) { plugin_file_from_fixtures("100x100.jpg") }
     let(:upload) { UploadCreator.new(image, "image.jpg").create_for(Discourse.system_user.id) }