PresentationConnection.cpp

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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 "PresentationConnection.h"

#include "ControllerConnectionCollection.h"
#include "mozilla/AsyncEventDispatcher.h"
#include "mozilla/dom/DOMException.h"
#include "mozilla/dom/File.h"
#include "mozilla/dom/MessageEvent.h"
#include "mozilla/dom/MessageEventBinding.h"
#include "mozilla/dom/PresentationConnectionCloseEvent.h"
#include "mozilla/ErrorNames.h"
#include "mozilla/DebugOnly.h"
#include "mozilla/IntegerPrintfMacros.h"
#include "nsContentUtils.h"
#include "nsCycleCollectionParticipant.h"
#include "nsIPresentationService.h"
#include "nsServiceManagerUtils.h"
#include "nsStringStream.h"
#include "PresentationConnectionList.h"
#include "PresentationLog.h"

namespace mozilla {
namespace dom {

NS_IMPL_CYCLE_COLLECTION_CLASS(PresentationConnection)

NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(PresentationConnection,
                                                  DOMEventTargetHelper)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mOwningConnectionList)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END

NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(PresentationConnection,
                                                DOMEventTargetHelper)
  tmp->Shutdown();
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mOwningConnectionList)
NS_IMPL_CYCLE_COLLECTION_UNLINK_END

NS_IMPL_ADDREF_INHERITED(PresentationConnection, DOMEventTargetHelper)
NS_IMPL_RELEASE_INHERITED(PresentationConnection, DOMEventTargetHelper)

NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(PresentationConnection)
  NS_INTERFACE_MAP_ENTRY(nsIPresentationSessionListener)
  NS_INTERFACE_MAP_ENTRY(nsIRequest)
NS_INTERFACE_MAP_END_INHERITING(DOMEventTargetHelper)

PresentationConnection::PresentationConnection(
    nsPIDOMWindowInner* aWindow, const nsAString& aId, const nsAString& aUrl,
    const uint8_t aRole, PresentationConnectionList* aList)
    : DOMEventTargetHelper(aWindow),
      mId(aId),
      mUrl(aUrl),
      mState(PresentationConnectionState::Connecting),
      mOwningConnectionList(aList),
      mBinaryType(PresentationConnectionBinaryType::Arraybuffer) {
  MOZ_ASSERT(aRole == nsIPresentationService::ROLE_CONTROLLER ||
             aRole == nsIPresentationService::ROLE_RECEIVER);
  mRole = aRole;
}

/* virtual */ PresentationConnection::~PresentationConnection() = default;

/* static */
already_AddRefed<PresentationConnection> PresentationConnection::Create(
    nsPIDOMWindowInner* aWindow, const nsAString& aId, const nsAString& aUrl,
    const uint8_t aRole, PresentationConnectionList* aList) {
  MOZ_ASSERT(aRole == nsIPresentationService::ROLE_CONTROLLER ||
             aRole == nsIPresentationService::ROLE_RECEIVER);
  RefPtr<PresentationConnection> connection =
      new PresentationConnection(aWindow, aId, aUrl, aRole, aList);
  if (NS_WARN_IF(!connection->Init())) {
    return nullptr;
  }

  if (aRole == nsIPresentationService::ROLE_CONTROLLER) {
    ControllerConnectionCollection::GetSingleton()->AddConnection(connection,
                                                                  aRole);
  }

  return connection.forget();
}

bool PresentationConnection::Init() {
  if (NS_WARN_IF(mId.IsEmpty())) {
    return false;
  }

  nsCOMPtr<nsIPresentationService> service =
      do_GetService(PRESENTATION_SERVICE_CONTRACTID);
  if (NS_WARN_IF(!service)) {
    return false;
  }

  nsresult rv = service->RegisterSessionListener(mId, mRole, this);
  if (NS_WARN_IF(NS_FAILED(rv))) {
    return false;
  }

  rv = AddIntoLoadGroup();
  if (NS_WARN_IF(NS_FAILED(rv))) {
    return false;
  }

  return true;
}

void PresentationConnection::Shutdown() {
  PRES_DEBUG("connection shutdown:id[%s], role[%d]\n",
             NS_ConvertUTF16toUTF8(mId).get(), mRole);

  nsCOMPtr<nsIPresentationService> service =
      do_GetService(PRESENTATION_SERVICE_CONTRACTID);
  if (NS_WARN_IF(!service)) {
    return;
  }

  DebugOnly<nsresult> rv = service->UnregisterSessionListener(mId, mRole);
  NS_WARNING_ASSERTION(NS_SUCCEEDED(rv), "UnregisterSessionListener failed");

  DebugOnly<nsresult> rv2 = RemoveFromLoadGroup();
  NS_WARNING_ASSERTION(NS_SUCCEEDED(rv2), "RemoveFromLoadGroup failed");

  if (mRole == nsIPresentationService::ROLE_CONTROLLER) {
    ControllerConnectionCollection::GetSingleton()->RemoveConnection(this,
                                                                     mRole);
  }
}

/* virtual */
void PresentationConnection::DisconnectFromOwner() {
  Unused << NS_WARN_IF(NS_FAILED(ProcessConnectionWentAway()));
  DOMEventTargetHelper::DisconnectFromOwner();
}

/* virtual */
JSObject* PresentationConnection::WrapObject(
    JSContext* aCx, JS::Handle<JSObject*> aGivenProto) {
  return PresentationConnection_Binding::Wrap(aCx, this, aGivenProto);
}

void PresentationConnection::GetId(nsAString& aId) const {
  if (nsContentUtils::ShouldResistFingerprinting()) {
    aId = EmptyString();
    return;
  }

  aId = mId;
}

void PresentationConnection::GetUrl(nsAString& aUrl) const {
  if (nsContentUtils::ShouldResistFingerprinting()) {
    aUrl = EmptyString();
    return;
  }

  aUrl = mUrl;
}

PresentationConnectionState PresentationConnection::State() const {
  if (nsContentUtils::ShouldResistFingerprinting()) {
    return PresentationConnectionState::Terminated;
  }

  return mState;
}

PresentationConnectionBinaryType PresentationConnection::BinaryType() const {
  if (nsContentUtils::ShouldResistFingerprinting()) {
    return PresentationConnectionBinaryType::Blob;
  }

  return mBinaryType;
}

void PresentationConnection::SetBinaryType(
    PresentationConnectionBinaryType aType) {
  if (nsContentUtils::ShouldResistFingerprinting()) {
    return;
  }

  mBinaryType = aType;
}

void PresentationConnection::Send(const nsAString& aData, ErrorResult& aRv) {
  if (nsContentUtils::ShouldResistFingerprinting()) {
    return;
  }

  // Sending is not allowed if the session is not connected.
  if (NS_WARN_IF(mState != PresentationConnectionState::Connected)) {
    aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
    return;
  }

  nsCOMPtr<nsIPresentationService> service =
      do_GetService(PRESENTATION_SERVICE_CONTRACTID);
  if (NS_WARN_IF(!service)) {
    AsyncCloseConnectionWithErrorMsg(
        u"Unable to send message due to an internal error."_ns);
    return;
  }

  nsresult rv = service->SendSessionMessage(mId, mRole, aData);
  if (NS_WARN_IF(NS_FAILED(rv))) {
    const uint32_t kMaxMessageLength = 256;
    nsAutoString data(Substring(aData, 0, kMaxMessageLength));

    AsyncCloseConnectionWithErrorMsg(u"Unable to send message: \""_ns + data +
                                     u"\""_ns);
  }
}

void PresentationConnection::Send(Blob& aData, ErrorResult& aRv) {
  if (nsContentUtils::ShouldResistFingerprinting()) {
    return;
  }

  if (NS_WARN_IF(mState != PresentationConnectionState::Connected)) {
    aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
    return;
  }

  nsCOMPtr<nsIPresentationService> service =
      do_GetService(PRESENTATION_SERVICE_CONTRACTID);
  if (NS_WARN_IF(!service)) {
    AsyncCloseConnectionWithErrorMsg(
        u"Unable to send message due to an internal error."_ns);
    return;
  }

  nsresult rv = service->SendSessionBlob(mId, mRole, &aData);
  if (NS_WARN_IF(NS_FAILED(rv))) {
    AsyncCloseConnectionWithErrorMsg(
        u"Unable to send binary message for Blob message."_ns);
  }
}

void PresentationConnection::Send(const ArrayBuffer& aData, ErrorResult& aRv) {
  if (nsContentUtils::ShouldResistFingerprinting()) {
    return;
  }

  if (NS_WARN_IF(mState != PresentationConnectionState::Connected)) {
    aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
    return;
  }

  nsCOMPtr<nsIPresentationService> service =
      do_GetService(PRESENTATION_SERVICE_CONTRACTID);
  if (NS_WARN_IF(!service)) {
    AsyncCloseConnectionWithErrorMsg(
        u"Unable to send message due to an internal error."_ns);
    return;
  }

  aData.ComputeState();

  static_assert(sizeof(*aData.Data()) == 1, "byte-sized data required");

  uint32_t length = aData.Length();
  char* data = reinterpret_cast<char*>(aData.Data());
  nsDependentCSubstring msgString(data, length);

  nsresult rv = service->SendSessionBinaryMsg(mId, mRole, msgString);
  if (NS_WARN_IF(NS_FAILED(rv))) {
    AsyncCloseConnectionWithErrorMsg(nsLiteralString(
        u"Unable to send binary message for ArrayBuffer message."));
  }
}

void PresentationConnection::Send(const ArrayBufferView& aData,
                                  ErrorResult& aRv) {
  if (nsContentUtils::ShouldResistFingerprinting()) {
    return;
  }

  if (NS_WARN_IF(mState != PresentationConnectionState::Connected)) {
    aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
    return;
  }

  nsCOMPtr<nsIPresentationService> service =
      do_GetService(PRESENTATION_SERVICE_CONTRACTID);
  if (NS_WARN_IF(!service)) {
    AsyncCloseConnectionWithErrorMsg(
        u"Unable to send message due to an internal error."_ns);
    return;
  }

  aData.ComputeState();

  static_assert(sizeof(*aData.Data()) == 1, "byte-sized data required");

  uint32_t length = aData.Length();
  char* data = reinterpret_cast<char*>(aData.Data());
  nsDependentCSubstring msgString(data, length);

  nsresult rv = service->SendSessionBinaryMsg(mId, mRole, msgString);
  if (NS_WARN_IF(NS_FAILED(rv))) {
    AsyncCloseConnectionWithErrorMsg(nsLiteralString(
        u"Unable to send binary message for ArrayBufferView message."));
  }
}

void PresentationConnection::Close(ErrorResult& aRv) {
  if (nsContentUtils::ShouldResistFingerprinting()) {
    return;
  }

  // It only works when the state is CONNECTED or CONNECTING.
  if (NS_WARN_IF(mState != PresentationConnectionState::Connected &&
                 mState != PresentationConnectionState::Connecting)) {
    return;
  }

  nsCOMPtr<nsIPresentationService> service =
      do_GetService(PRESENTATION_SERVICE_CONTRACTID);
  if (NS_WARN_IF(!service)) {
    aRv.Throw(NS_ERROR_DOM_OPERATION_ERR);
    return;
  }

  Unused << NS_WARN_IF(NS_FAILED(service->CloseSession(
      mId, mRole, nsIPresentationService::CLOSED_REASON_CLOSED)));
}

void PresentationConnection::Terminate(ErrorResult& aRv) {
  if (nsContentUtils::ShouldResistFingerprinting()) {
    return;
  }

  // It only works when the state is CONNECTED.
  if (NS_WARN_IF(mState != PresentationConnectionState::Connected)) {
    return;
  }

  nsCOMPtr<nsIPresentationService> service =
      do_GetService(PRESENTATION_SERVICE_CONTRACTID);
  if (NS_WARN_IF(!service)) {
    aRv.Throw(NS_ERROR_DOM_OPERATION_ERR);
    return;
  }

  Unused << NS_WARN_IF(NS_FAILED(service->TerminateSession(mId, mRole)));
}

bool PresentationConnection::Equals(uint64_t aWindowId, const nsAString& aId) {
  return GetOwner() && aWindowId == GetOwner()->WindowID() && mId.Equals(aId);
}

NS_IMETHODIMP
PresentationConnection::NotifyStateChange(const nsAString& aSessionId,
                                          uint16_t aState, nsresult aReason) {
  PRES_DEBUG("connection state change:id[%s], state[%" PRIx32
             "], reason[%" PRIx32 "], role[%d]\n",
             NS_ConvertUTF16toUTF8(aSessionId).get(), aState,
             static_cast<uint32_t>(aReason), mRole);

  if (!aSessionId.Equals(mId)) {
    return NS_ERROR_INVALID_ARG;
  }

  // A terminated connection should always remain in terminated.
  if (mState == PresentationConnectionState::Terminated) {
    return NS_OK;
  }

  PresentationConnectionState state;
  switch (aState) {
    case nsIPresentationSessionListener::STATE_CONNECTING:
      state = PresentationConnectionState::Connecting;
      break;
    case nsIPresentationSessionListener::STATE_CONNECTED:
      state = PresentationConnectionState::Connected;
      break;
    case nsIPresentationSessionListener::STATE_CLOSED:
      state = PresentationConnectionState::Closed;
      break;
    case nsIPresentationSessionListener::STATE_TERMINATED:
      state = PresentationConnectionState::Terminated;
      break;
    default:
      NS_WARNING("Unknown presentation session state.");
      return NS_ERROR_INVALID_ARG;
  }

  if (mState == state) {
    return NS_OK;
  }
  mState = state;

  nsresult rv = ProcessStateChanged(aReason);
  if (NS_WARN_IF(NS_FAILED(rv))) {
    return rv;
  }

  if (mOwningConnectionList) {
    mOwningConnectionList->NotifyStateChange(aSessionId, this);
  }

  return NS_OK;
}

nsresult PresentationConnection::ProcessStateChanged(nsresult aReason) {
  switch (mState) {
    case PresentationConnectionState::Connecting:
      return NS_OK;
    case PresentationConnectionState::Connected: {
      if (nsContentUtils::ShouldResistFingerprinting()) {
        return NS_OK;
      }

      RefPtr<AsyncEventDispatcher> asyncDispatcher =
          new AsyncEventDispatcher(this, u"connect"_ns, CanBubble::eNo);
      return asyncDispatcher->PostDOMEvent();
    }
    case PresentationConnectionState::Closed: {
      PresentationConnectionClosedReason reason =
          PresentationConnectionClosedReason::Closed;

      nsString errorMsg;
      if (NS_FAILED(aReason)) {
        reason = PresentationConnectionClosedReason::Error;
        nsCString name, message;

        // If aReason is not a DOM error, use error name as message.
        if (NS_FAILED(
                NS_GetNameAndMessageForDOMNSResult(aReason, name, message))) {
          GetErrorName(aReason, message);
          message.InsertLiteral("Internal error: ", 0);
        }
        CopyUTF8toUTF16(message, errorMsg);
      }

      Unused << NS_WARN_IF(
          NS_FAILED(DispatchConnectionCloseEvent(reason, errorMsg)));

      return RemoveFromLoadGroup();
    }
    case PresentationConnectionState::Terminated: {
      if (!nsContentUtils::ShouldResistFingerprinting()) {
        // Ensure onterminate event is fired.
        RefPtr<AsyncEventDispatcher> asyncDispatcher =
            new AsyncEventDispatcher(this, u"terminate"_ns, CanBubble::eNo);
        Unused << NS_WARN_IF(NS_FAILED(asyncDispatcher->PostDOMEvent()));
      }

      nsCOMPtr<nsIPresentationService> service =
          do_GetService(PRESENTATION_SERVICE_CONTRACTID);
      if (NS_WARN_IF(!service)) {
        return NS_ERROR_NOT_AVAILABLE;
      }

      nsresult rv = service->UnregisterSessionListener(mId, mRole);
      if (NS_WARN_IF(NS_FAILED(rv))) {
        return rv;
      }

      return RemoveFromLoadGroup();
    }
    default:
      MOZ_CRASH("Unknown presentation session state.");
      return NS_ERROR_INVALID_ARG;
  }
}

NS_IMETHODIMP
PresentationConnection::NotifyMessage(const nsAString& aSessionId,
                                      const nsACString& aData, bool aIsBinary) {
  PRES_DEBUG("connection %s:id[%s], data[%s], role[%d]\n", __func__,
             NS_ConvertUTF16toUTF8(aSessionId).get(),
             nsPromiseFlatCString(aData).get(), mRole);

  if (!aSessionId.Equals(mId)) {
    return NS_ERROR_INVALID_ARG;
  }

  // No message should be expected when the session is not connected.
  if (NS_WARN_IF(mState != PresentationConnectionState::Connected)) {
    return NS_ERROR_DOM_INVALID_STATE_ERR;
  }

  if (NS_WARN_IF(NS_FAILED(DoReceiveMessage(aData, aIsBinary)))) {
    AsyncCloseConnectionWithErrorMsg(u"Unable to receive a message."_ns);
    return NS_ERROR_FAILURE;
  }

  return NS_OK;
}

nsresult PresentationConnection::DoReceiveMessage(const nsACString& aData,
                                                  bool aIsBinary) {
  if (nsContentUtils::ShouldResistFingerprinting()) {
    return NS_OK;
  }

  // Transform the data.
  AutoJSAPI jsapi;
  if (!jsapi.Init(GetOwner())) {
    return NS_ERROR_FAILURE;
  }
  JSContext* cx = jsapi.cx();
  JS::Rooted<JS::Value> jsData(cx);

  nsresult rv;
  if (aIsBinary) {
    if (mBinaryType == PresentationConnectionBinaryType::Blob) {
      RefPtr<Blob> blob =
          Blob::CreateStringBlob(GetOwnerGlobal(), aData, EmptyString());
      if (NS_WARN_IF(!blob)) {
        return NS_ERROR_FAILURE;
      }

      if (!ToJSValue(cx, blob, &jsData)) {
        return NS_ERROR_FAILURE;
      }
    } else if (mBinaryType == PresentationConnectionBinaryType::Arraybuffer) {
      JS::Rooted<JSObject*> arrayBuf(cx);
      rv = nsContentUtils::CreateArrayBuffer(cx, aData, arrayBuf.address());
      if (NS_WARN_IF(NS_FAILED(rv))) {
        return rv;
      }
      jsData.setObject(*arrayBuf);
    } else {
      MOZ_CRASH("Unknown binary type!");
    }
  } else {
    NS_ConvertUTF8toUTF16 utf16Data(aData);
    if (NS_WARN_IF(!ToJSValue(cx, utf16Data, &jsData))) {
      return NS_ERROR_FAILURE;
    }
  }

  return DispatchMessageEvent(jsData);
}

nsresult PresentationConnection::DispatchConnectionCloseEvent(
    PresentationConnectionClosedReason aReason, const nsAString& aMessage,
    bool aDispatchNow) {
  if (nsContentUtils::ShouldResistFingerprinting()) {
    return NS_OK;
  }

  if (mState != PresentationConnectionState::Closed) {
    MOZ_ASSERT(false, "The connection state should be closed.");
    return NS_ERROR_FAILURE;
  }

  PresentationConnectionCloseEventInit init;
  init.mReason = aReason;
  init.mMessage = aMessage;

  RefPtr<PresentationConnectionCloseEvent> closedEvent =
      PresentationConnectionCloseEvent::Constructor(this, u"close"_ns, init);
  closedEvent->SetTrusted(true);

  if (aDispatchNow) {
    ErrorResult rv;
    DispatchEvent(*closedEvent, rv);
    return rv.StealNSResult();
  }

  RefPtr<AsyncEventDispatcher> asyncDispatcher =
      new AsyncEventDispatcher(this, closedEvent);
  return asyncDispatcher->PostDOMEvent();
}

nsresult PresentationConnection::DispatchMessageEvent(
    JS::Handle<JS::Value> aData) {
  nsCOMPtr<nsIGlobalObject> global = do_QueryInterface(GetOwner());
  if (NS_WARN_IF(!global)) {
    return NS_ERROR_NOT_AVAILABLE;
  }

  // Get the origin.
  nsAutoString origin;
  nsresult rv = nsContentUtils::GetUTFOrigin(global->PrincipalOrNull(), origin);
  if (NS_WARN_IF(NS_FAILED(rv))) {
    return rv;
  }

  RefPtr<MessageEvent> messageEvent = new MessageEvent(this, nullptr, nullptr);

  messageEvent->InitMessageEvent(
      nullptr, u"message"_ns, CanBubble::eNo, Cancelable::eNo, aData, origin,
      EmptyString(), nullptr, Sequence<OwningNonNull<MessagePort>>());
  messageEvent->SetTrusted(true);

  RefPtr<AsyncEventDispatcher> asyncDispatcher =
      new AsyncEventDispatcher(this, messageEvent);
  return asyncDispatcher->PostDOMEvent();
}

nsresult PresentationConnection::ProcessConnectionWentAway() {
  if (mState != PresentationConnectionState::Connected &&
      mState != PresentationConnectionState::Connecting) {
    // If the state is not connected or connecting, do not need to
    // close the session.
    return NS_OK;
  }

  mState = PresentationConnectionState::Terminated;

  nsCOMPtr<nsIPresentationService> service =
      do_GetService(PRESENTATION_SERVICE_CONTRACTID);
  if (NS_WARN_IF(!service)) {
    return NS_ERROR_NOT_AVAILABLE;
  }

  return service->CloseSession(mId, mRole,
                               nsIPresentationService::CLOSED_REASON_WENTAWAY);
}

NS_IMETHODIMP
PresentationConnection::GetName(nsACString& aResult) {
  aResult.AssignLiteral("about:presentation-connection");
  return NS_OK;
}

NS_IMETHODIMP
PresentationConnection::IsPending(bool* aRetval) {
  *aRetval = true;
  return NS_OK;
}

NS_IMETHODIMP
PresentationConnection::GetStatus(nsresult* aStatus) {
  *aStatus = NS_OK;
  return NS_OK;
}

NS_IMETHODIMP
PresentationConnection::Cancel(nsresult aStatus) {
  nsCOMPtr<nsIRunnable> event = NewRunnableMethod(
      "dom::PresentationConnection::ProcessConnectionWentAway", this,
      &PresentationConnection::ProcessConnectionWentAway);
  return NS_DispatchToCurrentThread(event);
}
NS_IMETHODIMP
PresentationConnection::Suspend(void) { return NS_ERROR_NOT_IMPLEMENTED; }
NS_IMETHODIMP
PresentationConnection::Resume(void) { return NS_ERROR_NOT_IMPLEMENTED; }

NS_IMETHODIMP
PresentationConnection::GetLoadGroup(nsILoadGroup** aLoadGroup) {
  *aLoadGroup = nullptr;

  nsCOMPtr<Document> doc = GetOwner() ? GetOwner()->GetExtantDoc() : nullptr;
  if (!doc) {
    return NS_ERROR_FAILURE;
  }

  *aLoadGroup = doc->GetDocumentLoadGroup().take();
  return NS_OK;
}

NS_IMETHODIMP
PresentationConnection::SetLoadGroup(nsILoadGroup* aLoadGroup) {
  return NS_ERROR_UNEXPECTED;
}

NS_IMETHODIMP
PresentationConnection::GetLoadFlags(nsLoadFlags* aLoadFlags) {
  *aLoadFlags = nsIRequest::LOAD_BACKGROUND;
  return NS_OK;
}

NS_IMETHODIMP
PresentationConnection::SetLoadFlags(nsLoadFlags aLoadFlags) { return NS_OK; }

NS_IMETHODIMP
PresentationConnection::GetTRRMode(nsIRequest::TRRMode* aTRRMode) {
  return GetTRRModeImpl(aTRRMode);
}

NS_IMETHODIMP
PresentationConnection::SetTRRMode(nsIRequest::TRRMode aTRRMode) {
  return SetTRRModeImpl(aTRRMode);
}

nsresult PresentationConnection::AddIntoLoadGroup() {
  // Avoid adding to loadgroup multiple times
  if (mWeakLoadGroup) {
    return NS_OK;
  }

  nsCOMPtr<nsILoadGroup> loadGroup;
  nsresult rv = GetLoadGroup(getter_AddRefs(loadGroup));
  if (NS_WARN_IF(NS_FAILED(rv))) {
    return rv;
  }

  rv = loadGroup->AddRequest(this, nullptr);
  if (NS_WARN_IF(NS_FAILED(rv))) {
    return rv;
  }

  mWeakLoadGroup = do_GetWeakReference(loadGroup);
  return NS_OK;
}

nsresult PresentationConnection::RemoveFromLoadGroup() {
  if (!mWeakLoadGroup) {
    return NS_OK;
  }

  nsCOMPtr<nsILoadGroup> loadGroup = do_QueryReferent(mWeakLoadGroup);
  if (loadGroup) {
    mWeakLoadGroup = nullptr;
    return loadGroup->RemoveRequest(this, nullptr, NS_OK);
  }

  return NS_OK;
}

void PresentationConnection::AsyncCloseConnectionWithErrorMsg(
    const nsAString& aMessage) {
  if (mState == PresentationConnectionState::Terminated) {
    return;
  }

  nsString message = nsString(aMessage);
  RefPtr<PresentationConnection> self = this;
  nsCOMPtr<nsIRunnable> r = NS_NewRunnableFunction(
      "dom::PresentationConnection::AsyncCloseConnectionWithErrorMsg",
      [self, message]() -> void {
        // Set |mState| to |PresentationConnectionState::Closed| here to avoid
        // calling |ProcessStateChanged|.
        self->mState = PresentationConnectionState::Closed;

        // Make sure dispatching the event and closing the connection are
        // invoked at the same time by setting |aDispatchNow| to true.
        Unused << NS_WARN_IF(NS_FAILED(self->DispatchConnectionCloseEvent(
            PresentationConnectionClosedReason::Error, message, true)));

        nsCOMPtr<nsIPresentationService> service =
            do_GetService(PRESENTATION_SERVICE_CONTRACTID);
        if (NS_WARN_IF(!service)) {
          return;
        }

        Unused << NS_WARN_IF(NS_FAILED(service->CloseSession(
            self->mId, self->mRole,
            nsIPresentationService::CLOSED_REASON_ERROR)));
      });

  Unused << NS_WARN_IF(NS_FAILED(NS_DispatchToMainThread(r)));
}

}  // namespace dom
}  // namespace mozilla