Possibly optimise download speed by rate-limiting update messages?

src/main/java/moe/nekojimi/chords/Chords.java

@@ -437,6 +437,9 @@ public final class Chords extends ListenerAdapter
 
         private static final String PROGRESS_SYMBOLS = " ▏▎▍▌▋▊▉█";
 
+        private double lastProgressUpdate = 0.0;
+        private boolean initialUpdateSent = false;
+
         /*
         ⠀⡀⣀⣠⣤⣦⣶⣾⣿
         🌑🌘🌗🌖🌕
@@ -455,6 +458,7 @@ public final class Chords extends ListenerAdapter
         @Override
         public void accept(TrackRequest request, Exception ex)
         {
+            boolean shouldUpdate = false;
             String response = "";
             if (request.getTracks().size() > 1)
                 response += "Downloading " + request.getTracks().size() + " tracks:\n";
@@ -467,6 +471,7 @@ public final class Chords extends ListenerAdapter
                     {
                         response += ("Finished downloading " + track + "!");
                         log("DOWN", "Downloaded " + track);
+                        shouldUpdate = true;
                     } else
                     {
                         Format format = track.getBestFormat();
@@ -482,7 +487,14 @@ public final class Chords extends ListenerAdapter
 
                         String progressDetails = "";
                         if (track.getProgress() >= 0)
+                        {
+                            if (track.getProgress() >= lastProgressUpdate + 10.0)
+                            {
+                                shouldUpdate = true;
+                                lastProgressUpdate = track.getProgress();
+                            }
                             progressDetails = " [" + String.format("%.1f", track.getProgress()) + "%]";
+                        }
 
                         response += ("Now downloading " + track + formatDetails + progressDetails + " ...");
                         log("DOWN", "Downloading " + track + "...");
@@ -491,11 +503,15 @@ public final class Chords extends ListenerAdapter
                 {
                     response += ("Failed to download " + track + "! Reason: " + ex.getMessage());
                     log("DOWN", "Failed to download " + track + "! Reason: " + ex.getMessage());
+                    shouldUpdate = true;
                 }
                 response += "\n";
             }
-            if (!response.isEmpty())
+            if (!response.isEmpty() && (shouldUpdate || initialUpdateSent))
+            {
                 request.getInvocation().respond(response);
+                initialUpdateSent = true;
+            }
         }
     }