/* -*- 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 "StorageNotifierService.h"

#include "mozilla/ClearOnShutdown.h"

#include "mozilla/StaticPtr.h"

namespace mozilla {

namespace dom {

namespace {

// This boolean is used to avoid the creation of the service after been

// distroyed on shutdown.

bool gStorageShuttingDown = false;

StaticRefPtr<StorageNotifierService> gStorageNotifierService;

} // anonymous

/* static */ StorageNotifierService*

StorageNotifierService::GetOrCreate()

{

  MOZ_ASSERT(NS_IsMainThread());

  if (!gStorageNotifierService && !gStorageShuttingDown) {

    gStorageNotifierService = new StorageNotifierService();

    ClearOnShutdown(&gStorageNotifierService);

  }

  return gStorageNotifierService;

}

StorageNotifierService::StorageNotifierService()

{

  MOZ_ASSERT(NS_IsMainThread());

  MOZ_ASSERT(!gStorageNotifierService);

}

StorageNotifierService::~StorageNotifierService()

{

  MOZ_ASSERT(NS_IsMainThread());

  MOZ_ASSERT(!gStorageNotifierService);

  gStorageShuttingDown = true;

}

/* static */ void

StorageNotifierService::Broadcast(StorageEvent* aEvent,

                                  const char16_t* aStorageType,

                                  bool aPrivateBrowsing,

                                  bool aImmediateDispatch)

{

  MOZ_ASSERT(NS_IsMainThread());

  RefPtr<StorageNotifierService> service = gStorageNotifierService;

  if (!service) {

    return;

  }

  RefPtr<StorageEvent> event = aEvent;

  nsTObserverArray<RefPtr<StorageNotificationObserver>>::ForwardIterator

    iter(service->mObservers);

  while (iter.HasMore()) {

    RefPtr<StorageNotificationObserver> observer = iter.GetNext();

    // Enforce that the source storage area's private browsing state matches

    // this window's state.  These flag checks and their maintenance independent

    // from the principal's OriginAttributes matter because chrome docshells

    // that are part of private browsing windows can be private browsing without

    // having their OriginAttributes set (because they have the system

    // principal).

    if (aPrivateBrowsing != observer->IsPrivateBrowsing()) {

      continue;

    }

    // No reasons to continue if the principal of the event doesn't match with

    // the window's one.

    if (!StorageUtils::PrincipalsEqual(aEvent->GetPrincipal(),

                                       observer->GetPrincipal())) {

      continue;

    }

    RefPtr<Runnable> r = NS_NewRunnableFunction(

      "StorageNotifierService::Broadcast",

      [observer, event, aStorageType, aPrivateBrowsing] () {

        observer->ObserveStorageNotification(event, aStorageType,

                                             aPrivateBrowsing);

      });

    if (aImmediateDispatch) {

      r->Run();

    } else {

      nsCOMPtr<nsIEventTarget> et = observer->GetEventTarget();

      if (et) {

        et->Dispatch(r.forget());

      }

    }

  }

}

void

StorageNotifierService::Register(StorageNotificationObserver* aObserver)

{

  MOZ_ASSERT(NS_IsMainThread());

  MOZ_ASSERT(aObserver);

  MOZ_ASSERT(!mObservers.Contains(aObserver));

  mObservers.AppendElement(aObserver);

}

void

StorageNotifierService::Unregister(StorageNotificationObserver* aObserver)

{

  MOZ_ASSERT(NS_IsMainThread());

  MOZ_ASSERT(aObserver);

  // No assertion about mObservers containing aObserver because window calls

  // this method multiple times.

  mObservers.RemoveElement(aObserver);

}

} // namespace dom

} // namespace mozilla