/* -*- 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 "VREventObserver.h"

#include "nsContentUtils.h"

#include "nsGlobalWindow.h"

#include "VRManagerChild.h"

#include "mozilla/Telemetry.h"

namespace mozilla {

namespace dom {

using namespace gfx;

/**

 * This class is used by nsGlobalWindow to implement window.onvrdisplayactivate,

 * window.onvrdisplaydeactivate, window.onvrdisplayconnected,

 * window.onvrdisplaydisconnected, and window.onvrdisplaypresentchange.

 */

VREventObserver::VREventObserver(nsGlobalWindowInner* aGlobalWindow)

  : mWindow(aGlobalWindow)

  , mIs2DView(true)

  , mHasReset(false)

{

  MOZ_ASSERT(aGlobalWindow);

  UpdateSpentTimeIn2DTelemetry(false);

  VRManagerChild* vmc = VRManagerChild::Get();

  if (vmc) {

    vmc->AddListener(this);

  }

}

VREventObserver::~VREventObserver()

{

  DisconnectFromOwner();

}

void

VREventObserver::DisconnectFromOwner()

{

  // In the event that nsGlobalWindow is deallocated, VREventObserver may

  // still be AddRef'ed elsewhere.  Ensure that we don't UAF by

  // dereferencing mWindow.

  UpdateSpentTimeIn2DTelemetry(true);

  mWindow = nullptr;

  // Unregister from VRManagerChild

  if (VRManagerChild::IsCreated()) {

    VRManagerChild* vmc = VRManagerChild::Get();

    vmc->RemoveListener(this);

  }

}

void

VREventObserver::UpdateSpentTimeIn2DTelemetry(bool aUpdate)

{

  // mHasReset for avoiding setting the telemetry continuously

  // for the telemetry is already been set when it is at the background.

  // then, it would be set again when the process is exit and calling

  // VREventObserver::DisconnectFromOwner().

  if (mWindow && mIs2DView && aUpdate && mHasReset) {

    // The WebVR content is closed, and we will collect the telemetry info

    // for the users who view it in 2D view only.

    Telemetry::Accumulate(Telemetry::WEBVR_USERS_VIEW_IN, 0);

    Telemetry::AccumulateTimeDelta(Telemetry::WEBVR_TIME_SPENT_VIEWING_IN_2D,

                                   mSpendTimeIn2DView);

    mHasReset = false;

  } else if (!aUpdate) {

    mSpendTimeIn2DView = TimeStamp::Now();

    mHasReset = true;

  }

}

void

VREventObserver::NotifyAfterLoad()

{

  if (VRManagerChild::IsCreated()) {

    VRManagerChild* vmc = VRManagerChild::Get();

    vmc->FireDOMVRDisplayConnectEventsForLoad(this);

  }

}

void

VREventObserver::NotifyVRDisplayMounted(uint32_t aDisplayID)

{

  if (mWindow && mWindow->AsInner()->IsCurrentInnerWindow()) {

    MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());

    mWindow->DispatchVRDisplayActivate(aDisplayID,

                                       VRDisplayEventReason::Mounted);

  }

}

void

VREventObserver::NotifyVRDisplayNavigation(uint32_t aDisplayID)

{

  if (mWindow && mWindow->AsInner()->IsCurrentInnerWindow()) {

    MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());

    mWindow->DispatchVRDisplayActivate(aDisplayID,

                                       VRDisplayEventReason::Navigation);

  }

}

void

VREventObserver::NotifyVRDisplayRequested(uint32_t aDisplayID)

{

  if (mWindow && mWindow->AsInner()->IsCurrentInnerWindow()) {

    MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());

    mWindow->DispatchVRDisplayActivate(aDisplayID,

                                       VRDisplayEventReason::Requested);

  }

}

void

VREventObserver::NotifyVRDisplayUnmounted(uint32_t aDisplayID)

{

  if (mWindow && mWindow->AsInner()->IsCurrentInnerWindow()) {

    MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());

    mWindow->DispatchVRDisplayDeactivate(aDisplayID,

                                         VRDisplayEventReason::Unmounted);

  }

}

void

VREventObserver::NotifyVRDisplayConnect(uint32_t aDisplayID)

{

  /**

   * We do not call nsGlobalWindow::NotifyActiveVRDisplaysChanged here, as we

   * can assume that a newly enumerated display is not presenting WebVR

   * content.

   */

  if (mWindow && mWindow->AsInner()->IsCurrentInnerWindow()) {

    MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());

    mWindow->DispatchVRDisplayConnect(aDisplayID);

  }

}

void

VREventObserver::NotifyVRDisplayDisconnect(uint32_t aDisplayID)

{

  if (mWindow && mWindow->AsInner()->IsCurrentInnerWindow()) {

    mWindow->NotifyActiveVRDisplaysChanged();

    MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());

    mWindow->DispatchVRDisplayDisconnect(aDisplayID);

  }

}

void

VREventObserver::NotifyVRDisplayPresentChange(uint32_t aDisplayID)

{

  // When switching to HMD present mode, it is no longer

  // to be a 2D view.

  mIs2DView = false;

  if (mWindow && mWindow->AsInner()->IsCurrentInnerWindow()) {

    mWindow->NotifyActiveVRDisplaysChanged();

    MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());

    mWindow->DispatchVRDisplayPresentChange(aDisplayID);

  }

}

void

VREventObserver::NotifyPresentationGenerationChanged(uint32_t aDisplayID) {

  if (mWindow && mWindow->AsInner()->IsCurrentInnerWindow()) {

    mWindow->NotifyPresentationGenerationChanged(aDisplayID);

    MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());

  }

}

} // namespace dom

} // namespace mozilla