messages#show with threads

app/controllers/messages_controller.rb

@@ -6,14 +6,7 @@ def index(list_name: nil, yyyymm: nil, q: nil, page: nil)
     if list_name
       @list = List.find_by_name list_name
 
-      @yyyymms = Message.where(list_id: @list).order('yyyymm').pluck(Arel.sql "distinct to_char(published_at, 'YYYYMM') as yyyymm")
-      @yyyymm = yyyymm || @yyyymms.last
-
-      root_query = Message.where(list_id: @list, parent_id: nil).where("to_char(published_at, 'YYYYMM') = ?", @yyyymm).order(:id)
-      messages = Message.with_recursive(parent_and_children: [root_query, Message.joins('inner join parent_and_children on messages.parent_id = parent_and_children.id')])
-        .joins('inner join parent_and_children on parent_and_children.id = messages.id')
-
-      @messages = compose_tree(messages)
+      render_threads yyyymm: yyyymm
     elsif q
       search q, page
 
@@ -29,10 +22,28 @@ def index(list_name: nil, yyyymm: nil, q: nil, page: nil)
   def show(list_name:, list_seq:)
     @list = List.find_by_name(list_name)
     @message = Message.find_by!(list_id: @list, list_seq: list_seq)
+
+    # If this is a turbo frame request, just render the message
+    return if turbo_frame_request?
+
+    render_threads yyyymm: @message.published_at.strftime('%Y%m')
   end
 
   private
 
+  def render_threads(yyyymm: nil)
+    @yyyymms = Message.where(list_id: @list).order('yyyymm').pluck(Arel.sql "distinct to_char(published_at, 'YYYYMM') as yyyymm")
+    @yyyymm = yyyymm || @yyyymms.last
+
+    root_query = Message.where(list_id: @list, parent_id: nil).where("to_char(published_at, 'YYYYMM') = ?", @yyyymm).order(:id)
+    messages = Message.with_recursive(parent_and_children: [root_query, Message.joins('inner join parent_and_children on messages.parent_id = parent_and_children.id')])
+      .joins('inner join parent_and_children on parent_and_children.id = messages.id')
+
+    @messages = compose_tree(messages)
+
+    render :index
+  end
+
   def get_list_ids(params)
     list_ids = []
     ['ruby-talk', 'ruby-core', 'ruby-list', 'ruby-dev'].each do |name|

app/javascript/controllers/message_list_controller.js

@@ -1,6 +1,16 @@
 import { Controller } from "@hotwired/stimulus"
 
 export default class extends Controller {
+  connect() {
+    // Scroll to selected message on page load, with a delay to ensure threads are expanded
+    setTimeout(() => {
+      const selected = this.element.querySelector('.message-selected')
+      if (selected) {
+        selected.scrollIntoView({behavior: 'smooth', block: 'center'})
+      }
+    }, 100)
+  }
+
   select(event) {
     // Remove highlight from previously selected message
     const previousSelected = this.element.querySelector('.message-selected')

app/javascript/controllers/thread_controller.js

@@ -5,9 +5,17 @@ export default class extends Controller {
   static targets = ["children", "icon"]
 
   connect() {
-    // Initially hide children
+    // Initially hide children unless one is selected
     if (this.hasChildrenTarget) {
-      this.childrenTarget.classList.add("hidden")
+      const hasSelectedChild = this.childrenTarget.querySelector('.message-selected')
+      if (hasSelectedChild) {
+        // Keep expanded and rotate icon
+        if (this.hasIconTarget) {
+          this.iconTarget.classList.add("rotate-90")
+        }
+      } else {
+        this.childrenTarget.classList.add("hidden")
+      }
     }
   }
 

app/views/messages/_thread.html.erb

@@ -1,6 +1,7 @@
 <div class="thread-message" style="margin-left: <%= depth * 6 %>px;" <% if (depth == 0) && message.children&.any? %>data-controller="thread"<% end %>>
+  <% selected = defined?(@message) && @message&.id == message.id %>
   <% if depth == 0 %>
-    <%= link_to [list, message], class: 'message-item block bg-white dark:bg-gray-800 rounded-lg shadow-md border border-gray-200 dark:border-gray-700 overflow-hidden hover:shadow-lg transition-shadow', data: {turbo_frame: 'message_content', turbo_action: 'advance', action: 'click->message-list#select'} do %>
+    <%= link_to [list, message], class: "message-item block bg-white dark:bg-gray-800 rounded-lg shadow-md border border-gray-200 dark:border-gray-700 overflow-hidden hover:shadow-lg transition-shadow#{' message-selected' if selected}", data: {turbo_frame: 'message_content', turbo_action: 'advance', action: 'click->message-list#select'} do %>
       <div class="p-5">
         <div class="flex items-start justify-between gap-4">
           <div class="flex-1 min-w-0">
@@ -35,7 +36,7 @@
       </div>
     <% end %>
   <% else %>
-    <%= link_to [list, message], class: 'message-item block py-2 border-l-2 border-gray-200 dark:border-gray-700 pl-4 hover:border-red-400 dark:hover:border-red-500 transition-colors', data: {turbo_frame: 'message_content', turbo_action: 'advance', action: 'click->message-list#select'} do %>
+    <%= link_to [list, message], class: "message-item block py-2 border-l-2 border-gray-200 dark:border-gray-700 pl-4 hover:border-red-400 dark:hover:border-red-500 transition-colors#{' message-selected' if selected}", data: {turbo_frame: 'message_content', turbo_action: 'advance', action: 'click->message-list#select'} do %>
       <div class="flex items-start gap-2 text-sm">
         <svg class="w-4 h-4 text-gray-400 dark:text-gray-500 mt-0.5 flex-shrink-0" fill="none" stroke="currentColor" viewBox="0 0 24 24">
           <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M3 10h10a8 8 0 018 8v2M3 10l6 6m-6-6l6-6"></path>

app/views/messages/index.html.erb

@@ -42,14 +42,18 @@
 
   <div class="col-span-3 overflow-y-auto">
     <%= turbo_frame_tag "message_content", class: "block" do %>
-      <div class="flex items-center justify-center h-full text-gray-400 dark:text-gray-500">
-        <div class="text-center">
-          <svg class="w-16 h-16 mx-auto mb-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-            <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M3 8l7.89 5.26a2 2 0 002.22 0L21 8M5 19h14a2 2 0 002-2V7a2 2 0 00-2-2H5a2 2 0 00-2 2v10a2 2 0 002 2z"></path>
-          </svg>
-          <p>Select a message to view</p>
+      <% if @message %>
+        <%= render @message %>
+      <% else %>
+        <div class="flex items-center justify-center h-full text-gray-400 dark:text-gray-500">
+          <div class="text-center">
+            <svg class="w-16 h-16 mx-auto mb-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+              <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M3 8l7.89 5.26a2 2 0 002.22 0L21 8M5 19h14a2 2 0 002-2V7a2 2 0 00-2-2H5a2 2 0 00-2 2v10a2 2 0 002 2z"></path>
+            </svg>
+            <p>Select a message to view</p>
+          </div>
         </div>
-      </div>
+      <% end %>
     <% end %>
   </div>
 </div>