MusicHandler: rewrite to use circular byte buffer.

Also now attempts to initially fill buffer in a single read.

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

@@ -10,7 +10,6 @@ import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.util.LinkedList;
 import java.util.Queue;
-import java.util.concurrent.ConcurrentLinkedQueue;
 import java.util.function.Consumer;
 import java.util.logging.Level;
 import java.util.logging.Logger;
@@ -19,6 +18,7 @@ import javax.sound.sampled.AudioInputStream;
 import javax.sound.sampled.AudioSystem;
 import javax.sound.sampled.UnsupportedAudioFileException;
 import net.dv8tion.jda.api.audio.AudioSendHandler;
+import org.apache.commons.io.input.buffer.CircularByteBuffer;
 
 /**
  *
@@ -27,10 +27,13 @@ import net.dv8tion.jda.api.audio.AudioSendHandler;
 public class MusicHandler implements AudioSendHandler, Closeable, Consumer<Song>
 {
 
+    private static final int DESIRED_BUFFER_SIZE = 3840 * 500;
+
     private final LinkedList<Song> songQueue = new LinkedList<>();
     private Song currentSong;
     private AudioInputStream din = null;
-    private final Queue<byte[]> queue = new ConcurrentLinkedQueue<>();
+//    private final Queue<byte[]> queue = new ConcurrentLinkedQueue<>();
+    private final CircularByteBuffer audioBuffer = new CircularByteBuffer(3840 * 1024);
     private boolean playing = true;
     private int byteCount;
 
@@ -80,7 +83,7 @@ public class MusicHandler implements AudioSendHandler, Closeable, Consumer<Song>
     public boolean nextSong(boolean immediate)
     {
         if (immediate)
-            queue.clear();
+            audioBuffer.clear();
 
         AudioInputStream in = null;
         try
@@ -104,10 +107,8 @@ public class MusicHandler implements AudioSendHandler, Closeable, Consumer<Song>
             AudioFormat decodedFormat = AudioSendHandler.INPUT_FORMAT;
             din = AudioSystem.getAudioInputStream(decodedFormat, in);
             byteCount = 3840;
-            while (queue.size() < 500)
-                if (!readData())
-                    break;
-            System.out.println("Queue filled to " + queue.size());
+            fillBuffer(false);
+            System.out.println("Queue filled to " + audioBuffer.getCurrentNumberOfBytes());
             return true;
         } catch (UnsupportedAudioFileException | IOException ex)
         {
@@ -134,19 +135,26 @@ public class MusicHandler implements AudioSendHandler, Closeable, Consumer<Song>
     public boolean canProvide()
     {
         // If we have something in our buffer we can provide it to the send system
-        return !queue.isEmpty() && playing;
+        return audioBuffer.getCurrentNumberOfBytes() > byteCount && playing;
     }
 
     @Override
     public ByteBuffer provide20MsAudio()
+    {
+        fillBuffer(true);
+        byte[] data = new byte[byteCount];
+        audioBuffer.read(data, 0, data.length);
+//        byte[] data = queue.poll();
+        return ByteBuffer.wrap(data); // Wrap this in a java.nio.ByteBuffer
+    }
+
+    private void fillBuffer(boolean canSkip)
     {
         // use what we have in our buffer to send audio as PCM
-        while (queue.size() < 500)
+        while (audioBuffer.getCurrentNumberOfBytes() < DESIRED_BUFFER_SIZE)
             if (!readData())
-                if (!nextSong())
+                if (!canSkip || !nextSong())
                     break;
-        byte[] data = queue.poll();
-        return data == null ? null : ByteBuffer.wrap(data); // Wrap this in a java.nio.ByteBuffer
     }
 
     private boolean readData()
@@ -157,15 +165,23 @@ public class MusicHandler implements AudioSendHandler, Closeable, Consumer<Song>
         {
             //				if (din.available() == 0)
             //					return false;
-            int bytesToRead = byteCount;
+            int bytesToRead = DESIRED_BUFFER_SIZE - audioBuffer.getCurrentNumberOfBytes();
+            int space = audioBuffer.getSpace();
             if (din.available() > 0 && din.available() < bytesToRead)
                 bytesToRead = din.available();
+            if (bytesToRead > space)
+                bytesToRead = space;
+            if (bytesToRead == 0)
+                return false;
             byte[] bytes = new byte[bytesToRead];
             //				byte[] bytes = din.readNBytes(bytesToRead);
             int read = din.read(bytes);
+            System.out.println("Wanted: " + byteCount + " Space:" + space + " Available: " + din.available() + " To read: " + bytesToRead + " Read: " + read);
             if (read < 0)
                 return false;
-            queue.add(bytes);
+//            queue.add(bytes);
+
+            audioBuffer.add(bytes, 0, read);
         } catch (IOException ex)
         {
             Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);