From 03c4bf266bc66641c2b28e86cb3eb37a0586a275 Mon Sep 17 00:00:00 2001
From: Krishna Penukonda <krishna@penukonda.me>
Date: Thu, 2 Jul 2026 09:51:53 +0000
Subject: [PATCH] feat: add recently edited section to /live page

- Broadcast edits on shared 'edits' PubSub topic
- Track recent edits in LiveLive with real-time updates
- Show up to 10 most recently edited non-live docs
- Fetch excerpts for recent docs on first edit broadcast
- Docs never appear in both live and recent sections
---
 lib/unfinal/document_server.ex    |  6 +++++
 lib/unfinal/documents.ex          |  3 +++
 lib/unfinal_web/live/live_live.ex | 44 +++++++++++++++++++++++++++++++
 3 files changed, 53 insertions(+)

diff --git a/lib/unfinal/document_server.ex b/lib/unfinal/document_server.ex
index b95f004..530d8ca 100644
--- a/lib/unfinal/document_server.ex
+++ b/lib/unfinal/document_server.ex
@@ -215,5 +215,11 @@ defmodule Unfinal.DocumentServer do
       path,
       %{content: doc.content, etag: doc.etag, revision: doc.revision}
     })
+
+    Phoenix.PubSub.broadcast(Unfinal.PubSub, Documents.edit_topic(), {
+      :edit,
+      path,
+      System.system_time(:second)
+    })
   end
 end
diff --git a/lib/unfinal/documents.ex b/lib/unfinal/documents.ex
index 378e5f4..99f1b06 100644
--- a/lib/unfinal/documents.ex
+++ b/lib/unfinal/documents.ex
@@ -19,6 +19,9 @@ defmodule Unfinal.Documents do
   def topic(path),
     do: @topic_prefix <> Base.url_encode64(ContentStore.normalize_path(path), padding: false)
 
+  @spec edit_topic() :: String.t()
+  def edit_topic, do: "edits"
+
   @spec get(path()) :: Document.t()
   def get(path), do: path |> ContentStore.normalize_path() |> server_call(:get)
 
diff --git a/lib/unfinal_web/live/live_live.ex b/lib/unfinal_web/live/live_live.ex
index 34a5459..0b1ca33 100644
--- a/lib/unfinal_web/live/live_live.ex
+++ b/lib/unfinal_web/live/live_live.ex
@@ -17,6 +17,7 @@ defmodule UnfinalWeb.LiveLive do
 
     if connected?(socket) do
       Phoenix.PubSub.subscribe(Unfinal.PubSub, @topic)
+      Phoenix.PubSub.subscribe(Unfinal.PubSub, Documents.edit_topic())
       active_paths = active_paths()
       Enum.each(active_paths, &Phoenix.PubSub.subscribe(Unfinal.PubSub, Documents.topic(&1)))
 
@@ -25,6 +26,7 @@ defmodule UnfinalWeb.LiveLive do
          active_paths: active_paths,
          sorted_paths: sorted_paths(),
          excerpts: excerpts(active_paths, %{}),
+         recent_edits: %{},
          authenticated: authenticated,
          user: user,
          claimed_namespace: claimed_namespace,
@@ -37,6 +39,7 @@ defmodule UnfinalWeb.LiveLive do
          active_paths: MapSet.new(),
          sorted_paths: [],
          excerpts: %{},
+         recent_edits: %{},
          authenticated: authenticated,
          user: user,
          claimed_namespace: claimed_namespace,
@@ -72,6 +75,20 @@ defmodule UnfinalWeb.LiveLive do
     end
   end
 
+  def handle_info({:edit, path, timestamp}, socket) do
+    socket = update(socket, :recent_edits, &Map.put(&1, path, timestamp))
+
+    socket =
+      if not MapSet.member?(socket.assigns.active_paths, path) and
+           not Map.has_key?(socket.assigns.excerpts, path) do
+        update(socket, :excerpts, &Map.put(&1, path, Documents.get(path).content))
+      else
+        socket
+      end
+
+    {:noreply, socket}
+  end
+
   @impl true
   def handle_event("toggle_mobile_menu", _params, socket) do
     {:noreply, assign(socket, mobile_menu_open: !socket.assigns.mobile_menu_open)}
@@ -120,6 +137,14 @@ defmodule UnfinalWeb.LiveLive do
   defp document_href("/" <> path), do: "/n/" <> path
   defp document_href(_path), do: "/n"
 
+  defp visible_recent(recent_edits, active_paths, limit \\ 10) do
+    recent_edits
+    |> Enum.reject(fn {path, _ts} -> MapSet.member?(active_paths, path) end)
+    |> Enum.sort_by(fn {_, ts} -> -ts end)
+    |> Enum.take(limit)
+    |> Enum.map(fn {path, _ts} -> path end)
+  end
+
   @impl true
   def render(assigns) do
     ~H"""
@@ -160,6 +185,25 @@ defmodule UnfinalWeb.LiveLive do
                 </p>
               </a>
             </div>
+
+            <% visible_recent = visible_recent(@recent_edits, @active_paths) %>
+
+            <div :if={visible_recent != []}>
+              <hr class="my-8 border-stone-200" />
+              <h2 class="text-xl font-semibold tracking-tight">Recently edited</h2>
+              <div class="mt-4 space-y-3">
+                <a
+                  :for={path <- visible_recent}
+                  href={document_href(path)}
+                  class="block rounded-2xl border border-stone-200 bg-white px-5 py-4 shadow-sm shadow-stone-200/40 transition hover:border-stone-300 hover:shadow-md"
+                >
+                  <div class="truncate text-sm font-semibold text-stone-900">{path}</div>
+                  <p :if={excerpt(Map.get(@excerpts, path, "")) != ""} class="mt-2 text-sm leading-6 text-stone-600">
+                    {excerpt(Map.get(@excerpts, path, ""))}
+                  </p>
+                </a>
+              </div>
+            </div>
           </section>
         </main>
       </div>