refactor: remove convoluted TrackLoader and LoadableSongs abstraction

BREAKING CHANGE: removed TrackLoader amd LoadableSongs

src/main/java/me/bobert/netneutrality/music/TrackLoadingHandler.java

@@ -17,16 +17,12 @@ import net.dv8tion.jda.api.entities.Guild;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
-import java.util.function.Consumer;
-
 public class TrackLoadingHandler implements AudioLoadResultHandler {
     private final Logger logger = LogManager.getLogger(TrackLoadingHandler.class);
 
     private final String identifier;
     private final SourceFinder.AudioSourceType type;
     private final boolean silent;
-    private Consumer<Boolean> loadConsumer;
-    private boolean loadingDisabled = false;
     private final Guild guild;
     private final TrackScheduler scheduler;
     private final CommandContext context;
@@ -40,24 +36,8 @@ public class TrackLoadingHandler implements AudioLoadResultHandler {
         this.context = context;
     }
 
-    public synchronized void stopLoading() {
-        logger.debug("Guild {}: stopped loading of new tracks", guild.getId());
-        loadingDisabled = true;
-    }
-
-    public void useCallbackOnLoad(Consumer<Boolean> consumer) {
-        this.loadConsumer = consumer;
-    }
-
     @Override
     public void trackLoaded(AudioTrack audioTrack) {
-        if (loadConsumer != null) {
-            loadConsumer.accept(true);
-        }
-
-        if (loadingDisabled)
-            return;
-
         context.deleteMessage();
 
         logger.debug("Guild {}: track loaded: {}", guild.getId(), audioTrack.getIdentifier());
@@ -70,13 +50,6 @@ public class TrackLoadingHandler implements AudioLoadResultHandler {
 
     @Override
     public void playlistLoaded(AudioPlaylist playlist) {
-        if (loadConsumer != null) {
-            loadConsumer.accept(true);
-        }
-
-        if (loadingDisabled)
-            return;
-
         logger.debug("Guild {}: playlist loaded: {}", guild.getId(), identifier);
 
         if (!playlist.getTracks().isEmpty()) {
@@ -96,10 +69,6 @@ public class TrackLoadingHandler implements AudioLoadResultHandler {
                 }
 
                 for (AudioTrack track : playlist.getTracks()) {
-                    if (loadingDisabled) {
-                        break;
-                    }
-
                     scheduler.getQueueManager().queue(track, context.getGuildUser());
                 }
             }
@@ -108,18 +77,12 @@ public class TrackLoadingHandler implements AudioLoadResultHandler {
 
     @Override
     public void noMatches() {
-        if (loadConsumer != null)
-            loadConsumer.accept(false);
-
         if (!silent)
             context.replyToMessage("No matches found");
     }
 
     @Override
     public void loadFailed(FriendlyException e) {
-        if (loadConsumer != null)
-            loadConsumer.accept(false);
-
         logger.debug("Guild {}: load failed for identifier {}", guild.getId(), identifier, e);
         LogHandler.log(e);