Fix `SonicAudioProcessor` end of stream behavior

The `AudioProcessor` interface requires that no more input is queued after
queueing end of stream, but `DefaultAudioSink` did queue more input and the
implementation of `SonicAudioProcessor` actually relied on this to drain output
at the end of the stream.

Fix this behavior by getting `Sonic` output in `getOutput` and having
`DefaultAudioSink` only queue input to processors that are not draining.

Also add TODOs to clean up audio processor implementations where the code
handles interaction that doesn't conform to the interface.

PiperOrigin-RevId: 345406478

extensions/gvr/src/main/java/com/google/android/exoplayer2/ext/gvr/GvrAudioProcessor.java

@@ -135,6 +135,7 @@ public class GvrAudioProcessor implements AudioProcessor {
 
 
   @Override
   @Override
   public void queueEndOfStream() {
   public void queueEndOfStream() {
+    // TODO(internal b/174554082): assert gvrAudioSurround is non-null here and in getOutput.
     if (gvrAudioSurround != null) {
     if (gvrAudioSurround != null) {
       gvrAudioSurround.triggerProcessing();
       gvrAudioSurround.triggerProcessing();
     }
     }

library/core/src/main/java/com/google/android/exoplayer2/audio/DefaultAudioSink.java

@@ -869,7 +869,9 @@ public final class DefaultAudioSink implements AudioSink {
         writeBuffer(input, avSyncPresentationTimeUs);
         writeBuffer(input, avSyncPresentationTimeUs);
       } else {
       } else {
         AudioProcessor audioProcessor = activeAudioProcessors[index];
         AudioProcessor audioProcessor = activeAudioProcessors[index];
-        audioProcessor.queueInput(input);
+        if (index > drainingAudioProcessorIndex) {
+          audioProcessor.queueInput(input);
+        }
         ByteBuffer output = audioProcessor.getOutput();
         ByteBuffer output = audioProcessor.getOutput();
         outputBuffers[index] = output;
         outputBuffers[index] = output;
         if (output.hasRemaining()) {
         if (output.hasRemaining()) {

library/core/src/main/java/com/google/android/exoplayer2/audio/SonicAudioProcessor.java

@@ -165,32 +165,20 @@ public final class SonicAudioProcessor implements AudioProcessor {
 
 
   @Override
   @Override
   public void queueInput(ByteBuffer inputBuffer) {
   public void queueInput(ByteBuffer inputBuffer) {
-    Sonic sonic = checkNotNull(this.sonic);
-    if (inputBuffer.hasRemaining()) {
-      ShortBuffer shortBuffer = inputBuffer.asShortBuffer();
-      int inputSize = inputBuffer.remaining();
-      inputBytes += inputSize;
-      sonic.queueInput(shortBuffer);
-      inputBuffer.position(inputBuffer.position() + inputSize);
-    }
-    int outputSize = sonic.getOutputSize();
-    if (outputSize > 0) {
-      if (buffer.capacity() < outputSize) {
-        buffer = ByteBuffer.allocateDirect(outputSize).order(ByteOrder.nativeOrder());
-        shortBuffer = buffer.asShortBuffer();
-      } else {
-        buffer.clear();
-        shortBuffer.clear();
-      }
-      sonic.getOutput(shortBuffer);
-      outputBytes += outputSize;
-      buffer.limit(outputSize);
-      outputBuffer = buffer;
+    if (!inputBuffer.hasRemaining()) {
+      return;
     }
     }
+    Sonic sonic = checkNotNull(this.sonic);
+    ShortBuffer shortBuffer = inputBuffer.asShortBuffer();
+    int inputSize = inputBuffer.remaining();
+    inputBytes += inputSize;
+    sonic.queueInput(shortBuffer);
+    inputBuffer.position(inputBuffer.position() + inputSize);
   }
   }
 
 
   @Override
   @Override
   public void queueEndOfStream() {
   public void queueEndOfStream() {
+    // TODO(internal b/174554082): assert sonic is non-null here and in getOutput.
     if (sonic != null) {
     if (sonic != null) {
       sonic.queueEndOfStream();
       sonic.queueEndOfStream();
     }
     }
@@ -199,6 +187,23 @@ public final class SonicAudioProcessor implements AudioProcessor {
 
 
   @Override
   @Override
   public ByteBuffer getOutput() {
   public ByteBuffer getOutput() {
+    @Nullable Sonic sonic = this.sonic;
+    if (sonic != null) {
+      int outputSize = sonic.getOutputSize();
+      if (outputSize > 0) {
+        if (buffer.capacity() < outputSize) {
+          buffer = ByteBuffer.allocateDirect(outputSize).order(ByteOrder.nativeOrder());
+          shortBuffer = buffer.asShortBuffer();
+        } else {
+          buffer.clear();
+          shortBuffer.clear();
+        }
+        sonic.getOutput(shortBuffer);
+        outputBytes += outputSize;
+        buffer.limit(outputSize);
+        outputBuffer = buffer;
+      }
+    }
     ByteBuffer outputBuffer = this.outputBuffer;
     ByteBuffer outputBuffer = this.outputBuffer;
     this.outputBuffer = EMPTY_BUFFER;
     this.outputBuffer = EMPTY_BUFFER;
     return outputBuffer;
     return outputBuffer;