gecko/dom/push/PushManager.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 "mozilla/dom/PushManager.h"

#include "mozilla/Preferences.h"
#include "mozilla/Services.h"
#include "mozilla/dom/PushManagerBinding.h"
#include "mozilla/dom/PushSubscriptionBinding.h"
#include "mozilla/dom/ServiceWorkerGlobalScopeBinding.h"

#include "mozilla/dom/Promise.h"
#include "mozilla/dom/PromiseWorkerProxy.h"

#include "nsIGlobalObject.h"
#include "nsIPermissionManager.h"
#include "nsIPrincipal.h"
#include "nsIPushClient.h"

#include "nsComponentManagerUtils.h"
#include "nsFrameMessageManager.h"
#include "nsContentCID.h"

#include "WorkerRunnable.h"
#include "WorkerPrivate.h"
#include "WorkerScope.h"

namespace mozilla {
namespace dom {

using namespace workers;

namespace {

nsresult
GetPermissionState(nsIPrincipal* aPrincipal,
                            PushPermissionState& aState)
{
  nsCOMPtr<nsIPermissionManager> permManager =
    mozilla::services::GetPermissionManager();

  if (!permManager) {
    return NS_ERROR_FAILURE;
  }
  uint32_t permission = nsIPermissionManager::UNKNOWN_ACTION;
  nsresult rv = permManager->TestExactPermissionFromPrincipal(
                  aPrincipal,
                  "desktop-notification",
                  &permission);
  if (NS_WARN_IF(NS_FAILED(rv))) {
    return rv;
  }

  if (permission == nsIPermissionManager::ALLOW_ACTION) {
    aState = PushPermissionState::Granted;
  } else if (permission == nsIPermissionManager::DENY_ACTION) {
    aState = PushPermissionState::Denied;
  } else {
    aState = PushPermissionState::Prompt;
  }
  return NS_OK;
}

} // anonymous namespace

class UnsubscribeResultCallback final : public nsIUnsubscribeResultCallback
{
public:
  NS_DECL_ISUPPORTS

  explicit UnsubscribeResultCallback(Promise* aPromise)
    : mPromise(aPromise)
  {
    AssertIsOnMainThread();
  }

  NS_IMETHOD
  OnUnsubscribe(nsresult aStatus, bool aSuccess) override
  {
    if (NS_SUCCEEDED(aStatus)) {
      mPromise->MaybeResolve(aSuccess);
    } else {
      mPromise->MaybeReject(NS_ERROR_DOM_NETWORK_ERR);
    }

    return NS_OK;
  }

private:
  ~UnsubscribeResultCallback()
  {}

  RefPtr<Promise> mPromise;
};

NS_IMPL_ISUPPORTS(UnsubscribeResultCallback, nsIUnsubscribeResultCallback)

already_AddRefed<Promise>
PushSubscription::Unsubscribe(ErrorResult& aRv)
{
  MOZ_ASSERT(mPrincipal);

  nsCOMPtr<nsIPushClient> client =
    do_CreateInstance("@mozilla.org/push/PushClient;1");
  if (NS_WARN_IF(!client)) {
    aRv = NS_ERROR_FAILURE;
    return nullptr;
  }

  RefPtr<Promise> p = Promise::Create(mGlobal, aRv);
  if (NS_WARN_IF(aRv.Failed())) {
    return nullptr;
  }

  RefPtr<UnsubscribeResultCallback> callback =
    new UnsubscribeResultCallback(p);
  client->Unsubscribe(mScope, mPrincipal, callback);
  return p.forget();
}

PushSubscription::PushSubscription(nsIGlobalObject* aGlobal,
                                   const nsAString& aEndpoint,
                                   const nsAString& aScope,
                                   const nsTArray<uint8_t>& aRawP256dhKey)
  : mGlobal(aGlobal)
  , mEndpoint(aEndpoint)
  , mScope(aScope)
  , mRawP256dhKey(aRawP256dhKey)
{
}

PushSubscription::~PushSubscription()
{
}

JSObject*
PushSubscription::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto)
{
  return PushSubscriptionBinding::Wrap(aCx, this, aGivenProto);
}

void
PushSubscription::GetKey(JSContext* aCx,
                         PushEncryptionKeyName aType,
                         JS::MutableHandle<JSObject*> aP256dhKey)
{
  if (aType == PushEncryptionKeyName::P256dh && !mRawP256dhKey.IsEmpty()) {
    aP256dhKey.set(ArrayBuffer::Create(aCx,
                                       mRawP256dhKey.Length(),
                                       mRawP256dhKey.Elements()));
  } else {
    aP256dhKey.set(nullptr);
  }
}

void
PushSubscription::SetPrincipal(nsIPrincipal* aPrincipal)
{
  MOZ_ASSERT(!mPrincipal);
  mPrincipal = aPrincipal;
}

// static
already_AddRefed<PushSubscription>
PushSubscription::Constructor(GlobalObject& aGlobal,
                              const nsAString& aEndpoint,
                              const nsAString& aScope,
                              const Nullable<ArrayBuffer>& aP256dhKey,
                              ErrorResult& aRv)
{
  MOZ_ASSERT(!aEndpoint.IsEmpty());
  MOZ_ASSERT(!aScope.IsEmpty());

  nsCOMPtr<nsIGlobalObject> global = do_QueryInterface(aGlobal.GetAsSupports());

  nsTArray<uint8_t> rawKey;
  if (!aP256dhKey.IsNull()) {
    const ArrayBuffer& key = aP256dhKey.Value();
    key.ComputeLengthAndData();
    rawKey.SetLength(key.Length());
    rawKey.ReplaceElementsAt(0, key.Length(), key.Data(), key.Length());
  }
  RefPtr<PushSubscription> sub = new PushSubscription(global,
                                                        aEndpoint,
                                                        aScope,
                                                        rawKey);

  return sub.forget();
}

NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(PushSubscription, mGlobal, mPrincipal)

NS_IMPL_CYCLE_COLLECTING_ADDREF(PushSubscription)
NS_IMPL_CYCLE_COLLECTING_RELEASE(PushSubscription)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(PushSubscription)
  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
  NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END

PushManager::PushManager(nsIGlobalObject* aGlobal, const nsAString& aScope)
  : mGlobal(aGlobal), mScope(aScope)
{
  AssertIsOnMainThread();
}

PushManager::~PushManager()
{}

JSObject*
PushManager::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto)
{
  // XXXnsm I don't know if this is the right way to do it, but I want to assert
  // that an implementation has been set before this object gets exposed to JS.
  MOZ_ASSERT(mImpl);
  return PushManagerBinding::Wrap(aCx, this, aGivenProto);
}

void
PushManager::SetPushManagerImpl(PushManagerImpl& foo, ErrorResult& aRv)
{
  MOZ_ASSERT(NS_IsMainThread());
  MOZ_ASSERT(!mImpl);
  mImpl = &foo;
}

already_AddRefed<Promise>
PushManager::Subscribe(ErrorResult& aRv)
{
  MOZ_ASSERT(mImpl);
  return mImpl->Subscribe(aRv);
}

already_AddRefed<Promise>
PushManager::GetSubscription(ErrorResult& aRv)
{
  MOZ_ASSERT(mImpl);
  return mImpl->GetSubscription(aRv);
}

already_AddRefed<Promise>
PushManager::PermissionState(ErrorResult& aRv)
{
  MOZ_ASSERT(mImpl);
  return mImpl->PermissionState(aRv);
}

NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(PushManager, mGlobal, mImpl)
NS_IMPL_CYCLE_COLLECTING_ADDREF(PushManager)
NS_IMPL_CYCLE_COLLECTING_RELEASE(PushManager)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(PushManager)
  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
  NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END

// WorkerPushSubscription

WorkerPushSubscription::WorkerPushSubscription(const nsAString& aEndpoint,
                                               const nsAString& aScope,
                                               const nsTArray<uint8_t>& aRawP256dhKey)
  : mEndpoint(aEndpoint), mScope(aScope), mRawP256dhKey(aRawP256dhKey)
{
  MOZ_ASSERT(!aScope.IsEmpty());
  MOZ_ASSERT(!aEndpoint.IsEmpty());
}

WorkerPushSubscription::~WorkerPushSubscription()
{}

JSObject*
WorkerPushSubscription::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto)
{
  return PushSubscriptionBinding_workers::Wrap(aCx, this, aGivenProto);
}

// static
already_AddRefed<WorkerPushSubscription>
WorkerPushSubscription::Constructor(GlobalObject& aGlobal,
                                    const nsAString& aEndpoint,
                                    const nsAString& aScope,
                                    const Nullable<ArrayBuffer>& aP256dhKey,
                                    ErrorResult& aRv)
{
  WorkerPrivate* worker = GetCurrentThreadWorkerPrivate();
  MOZ_ASSERT(worker);
  worker->AssertIsOnWorkerThread();

  nsTArray<uint8_t> rawKey;
  if (!aP256dhKey.IsNull()) {
    const ArrayBuffer& key = aP256dhKey.Value();
    key.ComputeLengthAndData();
    rawKey.SetLength(key.Length());
    rawKey.ReplaceElementsAt(0, key.Length(), key.Data(), key.Length());
  }
  RefPtr<WorkerPushSubscription> sub = new WorkerPushSubscription(aEndpoint,
                                                                    aScope,
                                                                    rawKey);

  return sub.forget();
}

void
WorkerPushSubscription::GetKey(JSContext* aCx,
                               PushEncryptionKeyName aType,
                               JS::MutableHandle<JSObject*> aP256dhKey)
{
  if (aType == mozilla::dom::PushEncryptionKeyName::P256dh &&
      !mRawP256dhKey.IsEmpty()) {
    aP256dhKey.set(ArrayBuffer::Create(aCx,
                                       mRawP256dhKey.Length(),
                                       mRawP256dhKey.Elements()));
  } else {
    aP256dhKey.set(nullptr);
  }
}

class UnsubscribeResultRunnable final : public WorkerRunnable
{
public:
  UnsubscribeResultRunnable(PromiseWorkerProxy* aProxy,
                            nsresult aStatus,
                            bool aSuccess)
    : WorkerRunnable(aProxy->GetWorkerPrivate(), WorkerThreadModifyBusyCount)
    , mProxy(aProxy)
    , mStatus(aStatus)
    , mSuccess(aSuccess)
  {
    AssertIsOnMainThread();
  }

  bool
  WorkerRun(JSContext* aCx, WorkerPrivate* aWorkerPrivate) override
  {
    MOZ_ASSERT(aWorkerPrivate);
    aWorkerPrivate->AssertIsOnWorkerThread();

    RefPtr<Promise> promise = mProxy->WorkerPromise();
    if (NS_SUCCEEDED(mStatus)) {
      promise->MaybeResolve(mSuccess);
    } else {
      promise->MaybeReject(NS_ERROR_DOM_NETWORK_ERR);
    }

    mProxy->CleanUp(aCx);
    return true;
  }
private:
  ~UnsubscribeResultRunnable()
  {}

  RefPtr<PromiseWorkerProxy> mProxy;
  nsresult mStatus;
  bool mSuccess;
};

class WorkerUnsubscribeResultCallback final : public nsIUnsubscribeResultCallback
{
public:
  NS_DECL_ISUPPORTS

  explicit WorkerUnsubscribeResultCallback(PromiseWorkerProxy* aProxy)
    : mProxy(aProxy)
  {
    AssertIsOnMainThread();
  }

  NS_IMETHOD
  OnUnsubscribe(nsresult aStatus, bool aSuccess) override
  {
    AssertIsOnMainThread();
    MOZ_ASSERT(mProxy, "OnUnsubscribe() called twice?");

    RefPtr<PromiseWorkerProxy> proxy = mProxy.forget();

    MutexAutoLock lock(proxy->Lock());
    if (proxy->CleanedUp()) {
      return NS_OK;
    }

    AutoJSAPI jsapi;
    jsapi.Init();

    RefPtr<UnsubscribeResultRunnable> r =
      new UnsubscribeResultRunnable(proxy, aStatus, aSuccess);
    r->Dispatch(jsapi.cx());
    return NS_OK;
  }

private:
  ~WorkerUnsubscribeResultCallback()
  {
  }

  RefPtr<PromiseWorkerProxy> mProxy;
};

NS_IMPL_ISUPPORTS(WorkerUnsubscribeResultCallback, nsIUnsubscribeResultCallback)

class UnsubscribeRunnable final : public nsRunnable
{
public:
  UnsubscribeRunnable(PromiseWorkerProxy* aProxy,
                      const nsAString& aScope)
    : mProxy(aProxy)
    , mScope(aScope)
  {
    MOZ_ASSERT(aProxy);
    MOZ_ASSERT(!aScope.IsEmpty());
  }

  NS_IMETHOD
  Run() override
  {
    AssertIsOnMainThread();
    MutexAutoLock lock(mProxy->Lock());
    if (mProxy->CleanedUp()) {
      return NS_OK;
    }

    RefPtr<WorkerUnsubscribeResultCallback> callback =
      new WorkerUnsubscribeResultCallback(mProxy);

    nsCOMPtr<nsIPushClient> client =
      do_CreateInstance("@mozilla.org/push/PushClient;1");
    if (!client) {
      callback->OnUnsubscribe(NS_ERROR_FAILURE, false);
      return NS_OK;
    }

    nsCOMPtr<nsIPrincipal> principal = mProxy->GetWorkerPrivate()->GetPrincipal();
    if (NS_WARN_IF(NS_FAILED(client->Unsubscribe(mScope, principal, callback)))) {
      callback->OnUnsubscribe(NS_ERROR_FAILURE, false);
      return NS_OK;
    }
    return NS_OK;
  }

private:
  ~UnsubscribeRunnable()
  {}

  RefPtr<PromiseWorkerProxy> mProxy;
  nsString mScope;
};

already_AddRefed<Promise>
WorkerPushSubscription::Unsubscribe(ErrorResult &aRv)
{
  WorkerPrivate* worker = GetCurrentThreadWorkerPrivate();
  MOZ_ASSERT(worker);
  worker->AssertIsOnWorkerThread();

  nsCOMPtr<nsIGlobalObject> global = worker->GlobalScope();
  RefPtr<Promise> p = Promise::Create(global, aRv);
  if (NS_WARN_IF(aRv.Failed())) {
    return nullptr;
  }

  RefPtr<PromiseWorkerProxy> proxy = PromiseWorkerProxy::Create(worker, p);
  if (!proxy) {
    p->MaybeReject(NS_ERROR_DOM_NETWORK_ERR);
    return p.forget();
  }

  RefPtr<UnsubscribeRunnable> r =
    new UnsubscribeRunnable(proxy, mScope);
  MOZ_ALWAYS_TRUE(NS_SUCCEEDED(NS_DispatchToMainThread(r)));

  return p.forget();
}

NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE_0(WorkerPushSubscription)

NS_IMPL_CYCLE_COLLECTING_ADDREF(WorkerPushSubscription)
NS_IMPL_CYCLE_COLLECTING_RELEASE(WorkerPushSubscription)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(WorkerPushSubscription)
  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
  NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END

// WorkerPushManager

WorkerPushManager::WorkerPushManager(const nsAString& aScope)
  : mScope(aScope)
{
}

JSObject*
WorkerPushManager::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto)
{
  return PushManagerBinding_workers::Wrap(aCx, this, aGivenProto);
}

class GetSubscriptionResultRunnable final : public WorkerRunnable
{
public:
  GetSubscriptionResultRunnable(PromiseWorkerProxy* aProxy,
                                nsresult aStatus,
                                const nsAString& aEndpoint,
                                const nsAString& aScope,
                                const nsTArray<uint8_t>& aRawP256dhKey)
    : WorkerRunnable(aProxy->GetWorkerPrivate(), WorkerThreadModifyBusyCount)
    , mProxy(aProxy)
    , mStatus(aStatus)
    , mEndpoint(aEndpoint)
    , mScope(aScope)
    , mRawP256dhKey(aRawP256dhKey)
  { }

  bool
  WorkerRun(JSContext* aCx, WorkerPrivate* aWorkerPrivate) override
  {
    RefPtr<Promise> promise = mProxy->WorkerPromise();
    if (NS_SUCCEEDED(mStatus)) {
      if (mEndpoint.IsEmpty()) {
        promise->MaybeResolve(JS::NullHandleValue);
      } else {
        RefPtr<WorkerPushSubscription> sub =
          new WorkerPushSubscription(mEndpoint, mScope, mRawP256dhKey);
        promise->MaybeResolve(sub);
      }
    } else {
      promise->MaybeReject(NS_ERROR_DOM_PUSH_ABORT_ERR);
    }

    mProxy->CleanUp(aCx);
    return true;
  }
private:
  ~GetSubscriptionResultRunnable()
  {}

  RefPtr<PromiseWorkerProxy> mProxy;
  nsresult mStatus;
  nsString mEndpoint;
  nsString mScope;
  nsTArray<uint8_t> mRawP256dhKey;
};

class GetSubscriptionCallback final : public nsIPushEndpointCallback
{
public:
  NS_DECL_ISUPPORTS

  explicit GetSubscriptionCallback(PromiseWorkerProxy* aProxy,
                                   const nsAString& aScope)
    : mProxy(aProxy)
    , mScope(aScope)
  {}

  NS_IMETHOD
  OnPushEndpoint(nsresult aStatus,
                 const nsAString& aEndpoint,
                 uint32_t aKeyLen,
                 uint8_t* aKey) override
  {
    AssertIsOnMainThread();
    MOZ_ASSERT(mProxy, "OnPushEndpoint() called twice?");

    RefPtr<PromiseWorkerProxy> proxy = mProxy.forget();

    MutexAutoLock lock(proxy->Lock());
    if (proxy->CleanedUp()) {
      return NS_OK;
    }

    AutoJSAPI jsapi;
    jsapi.Init();

    nsTArray<uint8_t> rawP256dhKey(aKeyLen);
    rawP256dhKey.ReplaceElementsAt(0, aKeyLen, aKey, aKeyLen);

    RefPtr<GetSubscriptionResultRunnable> r =
      new GetSubscriptionResultRunnable(proxy,
                                        aStatus,
                                        aEndpoint,
                                        mScope,
                                        rawP256dhKey);
    r->Dispatch(jsapi.cx());
    return NS_OK;
  }

protected:
  ~GetSubscriptionCallback()
  {}

private:
  RefPtr<PromiseWorkerProxy> mProxy;
  nsString mScope;
};

NS_IMPL_ISUPPORTS(GetSubscriptionCallback, nsIPushEndpointCallback)

class GetSubscriptionRunnable final : public nsRunnable
{
public:
  GetSubscriptionRunnable(PromiseWorkerProxy* aProxy,
                          const nsAString& aScope,
                          WorkerPushManager::SubscriptionAction aAction)
    : mProxy(aProxy)
    , mScope(aScope), mAction(aAction)
  {}

  NS_IMETHOD
  Run() override
  {
    AssertIsOnMainThread();
    MutexAutoLock lock(mProxy->Lock());
    if (mProxy->CleanedUp()) {
      return NS_OK;
    }

    RefPtr<GetSubscriptionCallback> callback = new GetSubscriptionCallback(mProxy, mScope);

    nsCOMPtr<nsIPrincipal> principal = mProxy->GetWorkerPrivate()->GetPrincipal();

    PushPermissionState state;
    nsresult rv = GetPermissionState(principal, state);
    if (NS_FAILED(rv)) {
      callback->OnPushEndpoint(NS_ERROR_FAILURE, EmptyString(), 0, nullptr);
      return NS_OK;
    }

    if (state != PushPermissionState::Granted) {
      if (mAction == WorkerPushManager::GetSubscriptionAction) {
        callback->OnPushEndpoint(NS_OK, EmptyString(), 0, nullptr);
        return NS_OK;
      }
      callback->OnPushEndpoint(NS_ERROR_FAILURE, EmptyString(), 0, nullptr);
      return NS_OK;
    }

    nsCOMPtr<nsIPushClient> client =
      do_CreateInstance("@mozilla.org/push/PushClient;1");
    if (!client) {
      callback->OnPushEndpoint(NS_ERROR_FAILURE, EmptyString(), 0, nullptr);
      return NS_OK;
    }

    if (mAction == WorkerPushManager::SubscribeAction) {
      rv = client->Subscribe(mScope, principal, callback);
    } else {
      MOZ_ASSERT(mAction == WorkerPushManager::GetSubscriptionAction);
      rv = client->GetSubscription(mScope, principal, callback);
    }

    if (NS_WARN_IF(NS_FAILED(rv))) {
      callback->OnPushEndpoint(NS_ERROR_FAILURE, EmptyString(), 0, nullptr);
      return NS_OK;
    }

    return NS_OK;
  }

private:
  ~GetSubscriptionRunnable()
  {}

  RefPtr<PromiseWorkerProxy> mProxy;
  nsString mScope;
  WorkerPushManager::SubscriptionAction mAction;
};

already_AddRefed<Promise>
WorkerPushManager::PerformSubscriptionAction(SubscriptionAction aAction, ErrorResult& aRv)
{
  WorkerPrivate* worker = GetCurrentThreadWorkerPrivate();
  MOZ_ASSERT(worker);
  worker->AssertIsOnWorkerThread();

  nsCOMPtr<nsIGlobalObject> global = worker->GlobalScope();
  RefPtr<Promise> p = Promise::Create(global, aRv);
  if (NS_WARN_IF(aRv.Failed())) {
    return nullptr;
  }

  RefPtr<PromiseWorkerProxy> proxy = PromiseWorkerProxy::Create(worker, p);
  if (!proxy) {
    p->MaybeReject(NS_ERROR_DOM_PUSH_ABORT_ERR);
    return p.forget();
  }

  RefPtr<GetSubscriptionRunnable> r =
    new GetSubscriptionRunnable(proxy, mScope, aAction);
  MOZ_ALWAYS_TRUE(NS_SUCCEEDED(NS_DispatchToMainThread(r)));

  return p.forget();
}

already_AddRefed<Promise>
WorkerPushManager::Subscribe(ErrorResult& aRv)
{
  return PerformSubscriptionAction(SubscribeAction, aRv);
}

already_AddRefed<Promise>
WorkerPushManager::GetSubscription(ErrorResult& aRv)
{
  return PerformSubscriptionAction(GetSubscriptionAction, aRv);
}

class PermissionResultRunnable final : public WorkerRunnable
{
public:
  PermissionResultRunnable(PromiseWorkerProxy *aProxy,
                           nsresult aStatus,
                           PushPermissionState aState)
    : WorkerRunnable(aProxy->GetWorkerPrivate(), WorkerThreadModifyBusyCount)
    , mProxy(aProxy)
    , mStatus(aStatus)
    , mState(aState)
  {
    AssertIsOnMainThread();
  }

  bool
  WorkerRun(JSContext* aCx, WorkerPrivate* aWorkerPrivate) override
  {
    MOZ_ASSERT(aWorkerPrivate);
    aWorkerPrivate->AssertIsOnWorkerThread();

    RefPtr<Promise> promise = mProxy->WorkerPromise();
    if (NS_SUCCEEDED(mStatus)) {
      MOZ_ASSERT(uint32_t(mState) < ArrayLength(PushPermissionStateValues::strings));
      nsAutoCString stringState(PushPermissionStateValues::strings[uint32_t(mState)].value,
                                PushPermissionStateValues::strings[uint32_t(mState)].length);
      promise->MaybeResolve(NS_ConvertUTF8toUTF16(stringState));
    } else {
      promise->MaybeReject(aCx, JS::UndefinedHandleValue);
    }

    mProxy->CleanUp(aCx);
    return true;
  }

private:
  ~PermissionResultRunnable()
  {}

  RefPtr<PromiseWorkerProxy> mProxy;
  nsresult mStatus;
  PushPermissionState mState;
};

class PermissionStateRunnable final : public nsRunnable
{
public:
  explicit PermissionStateRunnable(PromiseWorkerProxy* aProxy)
    : mProxy(aProxy)
  {}

  NS_IMETHOD
  Run() override
  {
    AssertIsOnMainThread();
    MutexAutoLock lock(mProxy->Lock());
    if (mProxy->CleanedUp()) {
      return NS_OK;
    }

    PushPermissionState state;
    nsresult rv = GetPermissionState(
      mProxy->GetWorkerPrivate()->GetPrincipal(),
      state
    );

    AutoJSAPI jsapi;
    jsapi.Init();
    RefPtr<PermissionResultRunnable> r =
      new PermissionResultRunnable(mProxy, rv, state);
    r->Dispatch(jsapi.cx());
    return NS_OK;
  }

private:
  ~PermissionStateRunnable()
  {}

  RefPtr<PromiseWorkerProxy> mProxy;
};

already_AddRefed<Promise>
WorkerPushManager::PermissionState(ErrorResult& aRv)
{
  WorkerPrivate* worker = GetCurrentThreadWorkerPrivate();
  MOZ_ASSERT(worker);
  worker->AssertIsOnWorkerThread();

  nsCOMPtr<nsIGlobalObject> global = worker->GlobalScope();
  RefPtr<Promise> p = Promise::Create(global, aRv);
  if (NS_WARN_IF(aRv.Failed())) {
    return nullptr;
  }

  RefPtr<PromiseWorkerProxy> proxy = PromiseWorkerProxy::Create(worker, p);
  if (!proxy) {
    p->MaybeReject(worker->GetJSContext(), JS::UndefinedHandleValue);
    return p.forget();
  }

  RefPtr<PermissionStateRunnable> r =
    new PermissionStateRunnable(proxy);
  NS_DispatchToMainThread(r);

  return p.forget();
}

WorkerPushManager::~WorkerPushManager()
{}

NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE_0(WorkerPushManager)
NS_IMPL_CYCLE_COLLECTING_ADDREF(WorkerPushManager)
NS_IMPL_CYCLE_COLLECTING_RELEASE(WorkerPushManager)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(WorkerPushManager)
  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
  NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END
} // namespace dom
} // namespace mozilla