/* -*- 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 "FetchObserver.h"
#include "mozilla/dom/Event.h"

namespace mozilla {
namespace dom {

NS_IMPL_CYCLE_COLLECTION_CLASS(FetchObserver)

NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(FetchObserver,
                                                  DOMEventTargetHelper)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mFollowingSignal)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END

NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(FetchObserver,
                                                DOMEventTargetHelper)
  tmp->Unfollow();
NS_IMPL_CYCLE_COLLECTION_UNLINK_END

NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(FetchObserver)
NS_INTERFACE_MAP_END_INHERITING(DOMEventTargetHelper)

NS_IMPL_ADDREF_INHERITED(FetchObserver, DOMEventTargetHelper)
NS_IMPL_RELEASE_INHERITED(FetchObserver, DOMEventTargetHelper)

FetchObserver::FetchObserver(nsIGlobalObject* aGlobal,
                             AbortSignalImpl* aSignalImpl)
    : DOMEventTargetHelper(aGlobal), mState(FetchState::Requesting) {
  if (aSignalImpl) {
    Follow(aSignalImpl);
  }
}

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

FetchState FetchObserver::State() const { return mState; }

void FetchObserver::Abort() { SetState(FetchState::Aborted); }

void FetchObserver::SetState(FetchState aState) {
  MOZ_ASSERT(mState < aState);

  if (mState == FetchState::Aborted || mState == FetchState::Errored ||
      mState == FetchState::Complete) {
    // We are already in a final state.
    return;
  }

  // We cannot pass from Requesting to Complete directly.
  if (mState == FetchState::Requesting && aState == FetchState::Complete) {
    SetState(FetchState::Responding);
  }

  mState = aState;

  if (mState == FetchState::Aborted || mState == FetchState::Errored ||
      mState == FetchState::Complete) {
    Unfollow();
  }

  EventInit init;
  init.mBubbles = false;
  init.mCancelable = false;

  // TODO which kind of event should we dispatch here?

  RefPtr<Event> event = Event::Constructor(this, u"statechange"_ns, init);
  event->SetTrusted(true);

  DispatchEvent(*event);
}

}  // namespace dom
}  // namespace mozilla