/* -*- 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 "MediaStreamAudioSourceNode.h"

#include "mozilla/dom/MediaStreamAudioSourceNodeBinding.h"

#include "AudioNodeEngine.h"

#include "AudioNodeExternalInputStream.h"

#include "AudioStreamTrack.h"

#include "nsIDocument.h"

#include "mozilla/CORSMode.h"

#include "nsContentUtils.h"

#include "nsIScriptError.h"

namespace mozilla {

namespace dom {

NS_IMPL_CYCLE_COLLECTION_CLASS(MediaStreamAudioSourceNode)

NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(MediaStreamAudioSourceNode)

  tmp->Destroy();

  NS_IMPL_CYCLE_COLLECTION_UNLINK(mInputStream)

  NS_IMPL_CYCLE_COLLECTION_UNLINK(mInputTrack)

NS_IMPL_CYCLE_COLLECTION_UNLINK_END_INHERITED(AudioNode)

NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(MediaStreamAudioSourceNode, AudioNode)

  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mInputStream)

  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mInputTrack)

NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END

NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(MediaStreamAudioSourceNode)

NS_INTERFACE_MAP_END_INHERITING(AudioNode)

NS_IMPL_ADDREF_INHERITED(MediaStreamAudioSourceNode, AudioNode)

NS_IMPL_RELEASE_INHERITED(MediaStreamAudioSourceNode, AudioNode)

MediaStreamAudioSourceNode::MediaStreamAudioSourceNode(AudioContext* aContext)

  : AudioNode(aContext,

              2,

              ChannelCountMode::Max,

              ChannelInterpretation::Speakers)

{

}

/* static */ already_AddRefed<MediaStreamAudioSourceNode>

MediaStreamAudioSourceNode::Create(AudioContext& aAudioContext,

                                   const MediaStreamAudioSourceOptions& aOptions,

                                   ErrorResult& aRv)

{

  if (aAudioContext.IsOffline()) {

    aRv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);

    return nullptr;

  }

  if (aAudioContext.CheckClosed(aRv)) {

    return nullptr;

  }

  if (aAudioContext.Graph() != aOptions.mMediaStream->GetPlaybackStream()->Graph()) {

    nsCOMPtr<nsPIDOMWindowInner> pWindow = aAudioContext.GetParentObject();

    nsIDocument* document = pWindow ? pWindow->GetExtantDoc() : nullptr;

    nsContentUtils::ReportToConsole(nsIScriptError::warningFlag,

                                    NS_LITERAL_CSTRING("Web Audio"),

                                    document,

                                    nsContentUtils::eDOM_PROPERTIES,

                                    "MediaStreamAudioSourceNodeDifferentRate");

    aRv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);

    return nullptr;

  }

  RefPtr<MediaStreamAudioSourceNode> node =

    new MediaStreamAudioSourceNode(&aAudioContext);

  node->Init(aOptions.mMediaStream, aRv);

  if (aRv.Failed()) {

    return nullptr;

  }

  return node.forget();

}

void

MediaStreamAudioSourceNode::Init(DOMMediaStream* aMediaStream, ErrorResult& aRv)

{

  if (!aMediaStream) {

    aRv.Throw(NS_ERROR_FAILURE);

    return;

  }

  MediaStream* inputStream = aMediaStream->GetPlaybackStream();

  MediaStreamGraph* graph = Context()->Graph();

  if (NS_WARN_IF(graph != inputStream->Graph())) {

    aRv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);

    return;

  }

  mInputStream = aMediaStream;

  AudioNodeEngine* engine = new MediaStreamAudioSourceNodeEngine(this);

  mStream = AudioNodeExternalInputStream::Create(graph, engine);

  mInputStream->AddConsumerToKeepAlive(ToSupports(this));

  mInputStream->RegisterTrackListener(this);

  AttachToFirstTrack(mInputStream);

}

void

MediaStreamAudioSourceNode::Destroy()

{

  if (mInputStream) {

    mInputStream->UnregisterTrackListener(this);

    mInputStream = nullptr;

  }

  DetachFromTrack();

}

MediaStreamAudioSourceNode::~MediaStreamAudioSourceNode()

{

  Destroy();

}

void

MediaStreamAudioSourceNode::AttachToTrack(const RefPtr<MediaStreamTrack>& aTrack)

{

  MOZ_ASSERT(!mInputTrack);

  MOZ_ASSERT(aTrack->AsAudioStreamTrack());

  if (!mStream) {

    return;

  }

  mInputTrack = aTrack;

  ProcessedMediaStream* outputStream =

    static_cast<ProcessedMediaStream*>(mStream.get());

  mInputPort = mInputTrack->ForwardTrackContentsTo(outputStream);

  PrincipalChanged(mInputTrack); // trigger enabling/disabling of the connector

  mInputTrack->AddPrincipalChangeObserver(this);

}

void

MediaStreamAudioSourceNode::DetachFromTrack()

{

  if (mInputTrack) {

    mInputTrack->RemovePrincipalChangeObserver(this);

    mInputTrack = nullptr;

  }

  if (mInputPort) {

    mInputPort->Destroy();

    mInputPort = nullptr;

  }

}

void

MediaStreamAudioSourceNode::AttachToFirstTrack(const RefPtr<DOMMediaStream>& aMediaStream)

{

  nsTArray<RefPtr<AudioStreamTrack>> tracks;

  aMediaStream->GetAudioTracks(tracks);

  for (const RefPtr<AudioStreamTrack>& track : tracks) {

    if (track->Ended()) {

      continue;

    }

    AttachToTrack(track);

    MarkActive();

    return;

  }

  // There was no track available. We'll allow the node to be garbage collected.

  MarkInactive();

}

void

MediaStreamAudioSourceNode::NotifyTrackAdded(const RefPtr<MediaStreamTrack>& aTrack)

{

  if (mInputTrack) {

    return;

  }

  if (!aTrack->AsAudioStreamTrack()) {

    return;

  }

  AttachToTrack(aTrack);

}

void

MediaStreamAudioSourceNode::NotifyTrackRemoved(const RefPtr<MediaStreamTrack>& aTrack)

{

  if (aTrack != mInputTrack) {

    return;

  }

  DetachFromTrack();

  AttachToFirstTrack(mInputStream);

}

/**

 * Changes the principal. Note that this will be called on the main thread, but

 * changes will be enacted on the MediaStreamGraph thread. If the principal

 * change results in the document principal losing access to the stream, then

 * there needs to be other measures in place to ensure that any media that is

 * governed by the new stream principal is not available to the MediaStreamGraph

 * before this change completes. Otherwise, a site could get access to

 * media that they are not authorized to receive.

 *

 * One solution is to block the altered content, call this method, then dispatch

 * another change request to the MediaStreamGraph thread that allows the content

 * under the new principal to flow. This might be unnecessary if the principal

 * change is changing to be the document principal.

 */

void

MediaStreamAudioSourceNode::PrincipalChanged(MediaStreamTrack* aMediaStreamTrack)

{

  MOZ_ASSERT(aMediaStreamTrack == mInputTrack);

  bool subsumes = false;

  nsIDocument* doc = nullptr;

  if (nsPIDOMWindowInner* parent = Context()->GetParentObject()) {

    doc = parent->GetExtantDoc();

    if (doc) {

      nsIPrincipal* docPrincipal = doc->NodePrincipal();

      nsIPrincipal* trackPrincipal = aMediaStreamTrack->GetPrincipal();

      if (!trackPrincipal || NS_FAILED(docPrincipal->Subsumes(trackPrincipal, &subsumes))) {

        subsumes = false;

      }

    }

  }

  auto stream = static_cast<AudioNodeExternalInputStream*>(mStream.get());

  bool enabled = subsumes || aMediaStreamTrack->GetCORSMode() != CORS_NONE;

  stream->SetInt32Parameter(MediaStreamAudioSourceNodeEngine::ENABLE, enabled);

  if (!enabled && doc) {

    nsContentUtils::ReportToConsole(nsIScriptError::warningFlag,

                                    NS_LITERAL_CSTRING("Web Audio"),

                                    doc,

                                    nsContentUtils::eDOM_PROPERTIES,

                                    CrossOriginErrorString());

  }

}

size_t

MediaStreamAudioSourceNode::SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const

{

  // Future:

  // - mInputStream

  size_t amount = AudioNode::SizeOfExcludingThis(aMallocSizeOf);

  if (mInputPort) {

    amount += mInputPort->SizeOfIncludingThis(aMallocSizeOf);

  }

  return amount;

}

size_t

MediaStreamAudioSourceNode::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const

{

  return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);

}

void

MediaStreamAudioSourceNode::DestroyMediaStream()

{

  if (mInputPort) {

    mInputPort->Destroy();

    mInputPort = nullptr;

  }

  AudioNode::DestroyMediaStream();

}

JSObject*

MediaStreamAudioSourceNode::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto)

{

  return MediaStreamAudioSourceNode_Binding::Wrap(aCx, this, aGivenProto);

}

} // namespace dom

} // namespace mozilla