Move pop to the Downloader classes

src/plugin/downloader.cr

@@ -5,5 +5,20 @@ class Plugin
     def initialize
       super
     end
+
+    def pop : Queue::Job?
+      job = nil
+      DB.open "sqlite3://#{@queue.path}" do |db|
+        begin
+          db.query_one "select * from queue where id like '%-%' and " \
+                       "(status = 0 or status = 1) order by time limit 1" \
+                       do |res|
+            job = Queue::Job.from_query_result res
+          end
+        rescue
+        end
+      end
+      job
+    end
   end
 end