channels sorted by last published video

src/invidious/database/channels.cr

@@ -85,6 +85,25 @@ module Invidious::Database::Channels
 
     return PG_DB.query_all(request, ids, as: InvidiousChannel)
   end
+
+  # Select channels sorted by last published video
+  def select_sorted(ids : Array(String)) : Array(InvidiousChannel)?
+    return [] of InvidiousChannel if ids.empty?
+  
+    request = <<-SQL
+      WITH max_published AS (
+        SELECT ucid, MAX(published) AS last_published
+        FROM channel_videos
+        GROUP BY ucid
+      )
+      SELECT channels.id, channels.author, channels.subscribed, channels.updated, channels.deleted FROM channels
+      LEFT JOIN max_published ON channels.id = max_published.ucid
+      WHERE channels.id = ANY($1)
+      ORDER BY max_published.last_published DESC NULLS LAST;
+    SQL
+  
+    return PG_DB.query_all(request, ids, as: InvidiousChannel)
+  end
 end
 
 #

src/invidious/routes/api/v1/authenticated.cr

@@ -153,7 +153,12 @@ module Invidious::Routes::API::V1::Authenticated
     env.response.content_type = "application/json"
     user = env.get("user").as(User)
 
-    subscriptions = Invidious::Database::Channels.select(user.subscriptions)
+    sorted = env.params.query["sorted"]?.try &.== "true"
+    if sorted
+      subscriptions = Invidious::Database::Channels.select_sorted(user.subscriptions)
+    else
+      subscriptions = Invidious::Database::Channels.select(user.subscriptions)
+    end
 
     JSON.build do |json|
       json.array do