gecko/content/media/webaudio/AudioContext.cpp

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "AudioContext.h"
#include "nsContentUtils.h"
#include "nsIDOMWindow.h"
#include "nsPIDOMWindow.h"
#include "mozilla/ErrorResult.h"
#include "MediaStreamGraph.h"
#include "AudioDestinationNode.h"
#include "AudioBufferSourceNode.h"
#include "AudioBuffer.h"
#include "GainNode.h"
#include "DelayNode.h"
#include "PannerNode.h"
#include "AudioListener.h"
#include "DynamicsCompressorNode.h"
#include "BiquadFilterNode.h"
#include "nsNetUtil.h"

namespace mozilla {
namespace dom {

NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE_3(AudioContext,
                                        mWindow, mDestination, mListener)

NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(AudioContext, AddRef)
NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(AudioContext, Release)

static uint8_t gWebAudioOutputKey;

AudioContext::AudioContext(nsIDOMWindow* aWindow)
  : mWindow(aWindow)
  , mDestination(new AudioDestinationNode(this, MediaStreamGraph::GetInstance()))
{
  // Actually play audio
  mDestination->Stream()->AddAudioOutput(&gWebAudioOutputKey);
  SetIsDOMBinding();
}

AudioContext::~AudioContext()
{
}

JSObject*
AudioContext::WrapObject(JSContext* aCx, JSObject* aScope)
{
  return AudioContextBinding::Wrap(aCx, aScope, this);
}

/* static */ already_AddRefed<AudioContext>
AudioContext::Constructor(const GlobalObject& aGlobal, ErrorResult& aRv)
{
  nsCOMPtr<nsPIDOMWindow> window = do_QueryInterface(aGlobal.Get());
  if (!window) {
    aRv.Throw(NS_ERROR_FAILURE);
    return nullptr;
  }

  nsRefPtr<AudioContext> object = new AudioContext(window);
  window->AddAudioContext(object);
  return object.forget();
}

already_AddRefed<AudioBufferSourceNode>
AudioContext::CreateBufferSource()
{
  nsRefPtr<AudioBufferSourceNode> bufferNode =
    new AudioBufferSourceNode(this);
  return bufferNode.forget();
}

already_AddRefed<AudioBuffer>
AudioContext::CreateBuffer(JSContext* aJSContext, uint32_t aNumberOfChannels,
                           uint32_t aLength, float aSampleRate,
                           ErrorResult& aRv)
{
  if (aSampleRate < 8000 || aSampleRate > 96000) {
    aRv.Throw(NS_ERROR_DOM_SYNTAX_ERR);
    return nullptr;
  }

  if (aLength > INT32_MAX) {
    aRv.Throw(NS_ERROR_OUT_OF_MEMORY);
    return nullptr;
  }

  nsRefPtr<AudioBuffer> buffer =
    new AudioBuffer(this, int32_t(aLength), aSampleRate);
  if (!buffer->InitializeBuffers(aNumberOfChannels, aJSContext)) {
    aRv.Throw(NS_ERROR_OUT_OF_MEMORY);
    return nullptr;
  }

  return buffer.forget();
}

already_AddRefed<GainNode>
AudioContext::CreateGain()
{
  nsRefPtr<GainNode> gainNode = new GainNode(this);
  return gainNode.forget();
}

already_AddRefed<DelayNode>
AudioContext::CreateDelay(double aMaxDelayTime, ErrorResult& aRv)
{
  if (aMaxDelayTime > 0. && aMaxDelayTime < 3.) {
    nsRefPtr<DelayNode> delayNode = new DelayNode(this, aMaxDelayTime);
    return delayNode.forget();
  }
  aRv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);
  return nullptr;
}

already_AddRefed<PannerNode>
AudioContext::CreatePanner()
{
  nsRefPtr<PannerNode> pannerNode = new PannerNode(this);
  return pannerNode.forget();
}

already_AddRefed<DynamicsCompressorNode>
AudioContext::CreateDynamicsCompressor()
{
  nsRefPtr<DynamicsCompressorNode> compressorNode =
    new DynamicsCompressorNode(this);
  return compressorNode.forget();
}

already_AddRefed<BiquadFilterNode>
AudioContext::CreateBiquadFilter()
{
  nsRefPtr<BiquadFilterNode> filterNode =
    new BiquadFilterNode(this);
  return filterNode.forget();
}

AudioListener*
AudioContext::Listener()
{
  if (!mListener) {
    mListener = new AudioListener(this);
  }
  return mListener;
}

void
AudioContext::DecodeAudioData(const ArrayBuffer& aBuffer,
                              DecodeSuccessCallback& aSuccessCallback,
                              const Optional<OwningNonNull<DecodeErrorCallback> >& aFailureCallback)
{
  // Sniff the content of the media.
  // Failed type sniffing will be handled by AsyncDecodeMedia.
  nsAutoCString contentType;
  NS_SniffContent(NS_DATA_SNIFFER_CATEGORY, nullptr,
                  aBuffer.Data(), aBuffer.Length(),
                  contentType);

  nsCOMPtr<DecodeErrorCallback> failureCallback;
  if (aFailureCallback.WasPassed()) {
    failureCallback = aFailureCallback.Value().get();
  }
  nsAutoPtr<WebAudioDecodeJob> job(
    new WebAudioDecodeJob(contentType, aBuffer, this,
                          &aSuccessCallback, failureCallback));
  mDecoder.AsyncDecodeMedia(contentType.get(),
                            job->mBuffer, job->mLength, *job);
  // Transfer the ownership to mDecodeJobs
  mDecodeJobs.AppendElement(job.forget());
}

void
AudioContext::RemoveFromDecodeQueue(WebAudioDecodeJob* aDecodeJob)
{
  mDecodeJobs.RemoveElement(aDecodeJob);
}

MediaStreamGraph*
AudioContext::Graph() const
{
  return Destination()->Stream()->Graph();
}

MediaStream*
AudioContext::DestinationStream() const
{
  return Destination()->Stream();
}

double
AudioContext::CurrentTime() const
{
  return MediaTimeToSeconds(Destination()->Stream()->GetCurrentTime());
}

void
AudioContext::Suspend()
{
  DestinationStream()->ChangeExplicitBlockerCount(1);
}

void
AudioContext::Resume()
{
  DestinationStream()->ChangeExplicitBlockerCount(-1);
}

}
}