feat: seed recently-edited from SQLite history

lib/unfinal/sqlite_documents.ex

@@ -138,6 +138,20 @@ defmodule Unfinal.SqliteDocuments do
     end
   end
 
+  @doc "List most recently edited documents across all namespaces."
+  @spec recent_edits(non_neg_integer()) :: [%{path: String.t(), updated_at: String.t()}]
+  def recent_edits(limit \\ 20) when is_integer(limit) and limit > 0 do
+    sql = "SELECT path, updated_at FROM documents WHERE updated_at IS NOT NULL ORDER BY updated_at DESC LIMIT ?1"
+
+    case query(sql, [limit]) do
+      {:ok, %{rows: rows}} ->
+        Enum.map(rows, fn [path, upd] -> %{path: path, updated_at: upd} end)
+
+      {:error, _} ->
+        []
+    end
+  end
+
   @doc "Count all document rows."
   @spec count_documents() :: non_neg_integer()
   def count_documents do

lib/unfinal_web/live/live_live.ex

@@ -3,6 +3,7 @@ defmodule UnfinalWeb.LiveLive do
 
   alias Unfinal.Documents
   alias Unfinal.NamespaceStore
+  alias Unfinal.SqliteDocuments
   alias UnfinalWeb.Layouts
   alias UnfinalWeb.Presence
 
@@ -21,12 +22,16 @@ defmodule UnfinalWeb.LiveLive do
       active_paths = active_paths()
       Enum.each(active_paths, &Phoenix.PubSub.subscribe(Unfinal.PubSub, Documents.topic(&1)))
 
+      recent_edits = seed_recent_edits()
+      recent_paths = Map.keys(recent_edits) -- MapSet.to_list(active_paths)
+      excerpts = excerpts(MapSet.union(active_paths, MapSet.new(recent_paths)), %{})
+
       {:ok,
        assign(socket,
          active_paths: active_paths,
          sorted_paths: sorted_paths(),
-         excerpts: excerpts(active_paths, %{}),
-         recent_edits: %{},
+         excerpts: excerpts,
+         recent_edits: recent_edits,
          authenticated: authenticated,
          user: user,
          claimed_namespace: claimed_namespace,
@@ -103,6 +108,21 @@ defmodule UnfinalWeb.LiveLive do
 
   defp claimed_namespace(_session), do: nil
 
+  defp seed_recent_edits do
+    SqliteDocuments.recent_edits(20)
+    |> Enum.map(fn %{path: path, updated_at: updated_at} ->
+      {path, parse_timestamp(updated_at)}
+    end)
+    |> Map.new()
+  end
+
+  defp parse_timestamp(iso_string) do
+    case DateTime.from_iso8601(iso_string) do
+      {:ok, dt, _} -> DateTime.to_unix(dt)
+      _ -> 0
+    end
+  end
+
   defp active_paths do
     @topic |> Presence.list() |> Map.keys() |> MapSet.new()
   end