gecko-dev/dom/permission/PermissionStatus.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/PermissionStatus.h"
#include "mozilla/PermissionDelegateHandler.h"

#include "mozilla/AsyncEventDispatcher.h"
#include "mozilla/Permission.h"
#include "mozilla/Services.h"
#include "nsIPermissionManager.h"
#include "PermissionObserver.h"
#include "PermissionUtils.h"

namespace mozilla::dom {

/* static */
already_AddRefed<PermissionStatus> PermissionStatus::Create(
    nsPIDOMWindowInner* aWindow, PermissionName aName, ErrorResult& aRv) {
  RefPtr<PermissionStatus> status = new PermissionStatus(aWindow, aName);
  aRv = status->Init();
  if (NS_WARN_IF(aRv.Failed())) {
    return nullptr;
  }

  return status.forget();
}

PermissionStatus::PermissionStatus(nsPIDOMWindowInner* aWindow,
                                   PermissionName aName)
    : DOMEventTargetHelper(aWindow),
      mName(aName),
      mState(PermissionState::Denied) {
  KeepAliveIfHasListenersFor(nsGkAtoms::onchange);
}

nsresult PermissionStatus::Init() {
  mObserver = PermissionObserver::GetInstance();
  if (NS_WARN_IF(!mObserver)) {
    return NS_ERROR_FAILURE;
  }

  mObserver->AddSink(this);

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

  return NS_OK;
}

PermissionStatus::~PermissionStatus() {
  if (mObserver) {
    mObserver->RemoveSink(this);
  }
}

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

nsresult PermissionStatus::UpdateState() {
  nsCOMPtr<nsPIDOMWindowInner> window = GetOwner();
  if (NS_WARN_IF(!window)) {
    return NS_ERROR_FAILURE;
  }

  RefPtr<Document> document = window->GetExtantDoc();
  if (NS_WARN_IF(!document)) {
    return NS_ERROR_FAILURE;
  }

  uint32_t action = nsIPermissionManager::DENY_ACTION;

  PermissionDelegateHandler* permissionHandler =
      document->GetPermissionDelegateHandler();
  if (NS_WARN_IF(!permissionHandler)) {
    return NS_ERROR_FAILURE;
  }

  nsresult rv = permissionHandler->GetPermissionForPermissionsAPI(
      PermissionNameToType(mName), &action);
  if (NS_WARN_IF(NS_FAILED(rv))) {
    return rv;
  }

  mState = ActionToPermissionState(action);
  return NS_OK;
}

already_AddRefed<nsIPrincipal> PermissionStatus::GetPrincipal() const {
  nsCOMPtr<nsPIDOMWindowInner> window = GetOwner();
  if (NS_WARN_IF(!window)) {
    return nullptr;
  }

  Document* doc = window->GetExtantDoc();
  if (NS_WARN_IF(!doc)) {
    return nullptr;
  }

  nsCOMPtr<nsIPrincipal> principal =
      Permission::ClonePrincipalForPermission(doc->NodePrincipal());
  NS_ENSURE_TRUE(principal, nullptr);

  return principal.forget();
}

void PermissionStatus::PermissionChanged() {
  nsCOMPtr<nsPIDOMWindowInner> window = GetOwner();
  if (NS_WARN_IF(!window) || !window->IsFullyActive()) {
    return;
  }
  auto oldState = mState;
  UpdateState();
  if (mState != oldState) {
    RefPtr<AsyncEventDispatcher> eventDispatcher =
        new AsyncEventDispatcher(this, u"change"_ns, CanBubble::eNo);
    eventDispatcher->PostDOMEvent();
  }
}

void PermissionStatus::DisconnectFromOwner() {
  IgnoreKeepAliveIfHasListenersFor(nsGkAtoms::onchange);

  if (mObserver) {
    mObserver->RemoveSink(this);
    mObserver = nullptr;
  }

  DOMEventTargetHelper::DisconnectFromOwner();
}

}  // namespace mozilla::dom