/* 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 "BackgroundChannelRegistrar.h"

#include "mozilla/ClearOnShutdown.h"
#include "mozilla/StaticPtr.h"
#include "HttpBackgroundChannelParent.h"
#include "HttpChannelParent.h"
#include "nsXULAppAPI.h"

namespace {
mozilla::StaticRefPtr<mozilla::net::BackgroundChannelRegistrar>
    gBackgroundChannelRegistrarSingleton;
}

namespace mozilla {
namespace net {

NS_IMPL_ISUPPORTS(BackgroundChannelRegistrar, nsIBackgroundChannelRegistrar)

BackgroundChannelRegistrar::BackgroundChannelRegistrar() {
  // BackgroundChannelRegistrar is a main-thread-only object.
  // All the operations should be run on main thread.
  // It should be used on chrome process only.
  MOZ_ASSERT(XRE_IsParentProcess());
  MOZ_ASSERT(NS_IsMainThread());
}

BackgroundChannelRegistrar::~BackgroundChannelRegistrar() {
  MOZ_ASSERT(NS_IsMainThread());
}

// static
already_AddRefed<BackgroundChannelRegistrar>
BackgroundChannelRegistrar::GetOrCreate() {
  if (!gBackgroundChannelRegistrarSingleton) {
    gBackgroundChannelRegistrarSingleton = new BackgroundChannelRegistrar();
    ClearOnShutdown(&gBackgroundChannelRegistrarSingleton);
  }
  return do_AddRef(gBackgroundChannelRegistrarSingleton);
}

void BackgroundChannelRegistrar::NotifyChannelLinked(
    HttpChannelParent* aChannelParent, HttpBackgroundChannelParent* aBgParent) {
  MOZ_ASSERT(NS_IsMainThread());
  MOZ_ASSERT(aChannelParent);
  MOZ_ASSERT(aBgParent);

  // Only link the two actors when they originate from the same content
  // process, since the channel Id used as the key is supplied by
  // the content process.
  if (aChannelParent->GetContentParentId() != aBgParent->GetContentParentId()) {
    return;
  }

  aBgParent->LinkToChannel(aChannelParent);
  aChannelParent->OnBackgroundParentReady(aBgParent);
}

// nsIBackgroundChannelRegistrar
void BackgroundChannelRegistrar::DeleteChannel(uint64_t aKey) {
  MOZ_ASSERT(NS_IsMainThread());

  RefPtr<HttpChannelParent> channel;
  mChannels.Remove(aKey, getter_AddRefs(channel));
  RefPtr<HttpBackgroundChannelParent> bgChannel;
  mBgChannels.Remove(aKey, getter_AddRefs(bgChannel));
}

void BackgroundChannelRegistrar::DeleteChannelIfMatches(
    uint64_t aKey, HttpChannelParent* aExpected) {
  MOZ_ASSERT(NS_IsMainThread());

  RefPtr<HttpChannelParent> channel;
  if (mChannels.GetWeak(aKey) == aExpected) {
    mChannels.Remove(aKey, getter_AddRefs(channel));
  }
  RefPtr<HttpBackgroundChannelParent> bgChannel;
  mBgChannels.Remove(aKey, getter_AddRefs(bgChannel));
}

void BackgroundChannelRegistrar::LinkHttpChannel(uint64_t aKey,
                                                 HttpChannelParent* aChannel) {
  MOZ_ASSERT(NS_IsMainThread());
  MOZ_ASSERT(aChannel);

  RefPtr<HttpBackgroundChannelParent> bgParent;
  bool found = mBgChannels.Remove(aKey, getter_AddRefs(bgParent));

  if (!found) {
    mChannels.InsertOrUpdate(aKey, RefPtr{aChannel});
    return;
  }

  MOZ_ASSERT(bgParent);
  NotifyChannelLinked(aChannel, bgParent);
}

void BackgroundChannelRegistrar::LinkBackgroundChannel(
    uint64_t aKey, HttpBackgroundChannelParent* aBgChannel) {
  MOZ_ASSERT(NS_IsMainThread());
  MOZ_ASSERT(aBgChannel);

  RefPtr<HttpChannelParent> parent;
  bool found = mChannels.Remove(aKey, getter_AddRefs(parent));

  if (!found) {
    mBgChannels.InsertOrUpdate(aKey, RefPtr{aBgChannel});
    return;
  }

  MOZ_ASSERT(parent);
  NotifyChannelLinked(parent, aBgChannel);
}

}  // namespace net
}  // namespace mozilla