/* 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/DocGroup.h"

#include "mozilla/AbstractThread.h"
#include "mozilla/SchedulerGroup.h"
#include "mozilla/StaticPrefs_dom.h"
#include "mozilla/ThrottledEventQueue.h"
#include "mozilla/dom/BlobURLProtocolHandler.h"
#include "mozilla/dom/BrowsingContext.h"
#include "mozilla/dom/CustomElementRegistry.h"
#include "mozilla/dom/DOMTypes.h"
#include "mozilla/dom/JSExecutionManager.h"
#include "mozilla/dom/MediaSource.h"
#include "mozilla/dom/WindowContext.h"
#include "nsDOMMutationObserver.h"
#include "nsIDirectTaskDispatcher.h"
#include "nsIXULRuntime.h"
#include "nsProxyRelease.h"
#include "nsThread.h"
#if defined(XP_WIN)
#  include <processthreadsapi.h>  // for GetCurrentProcessId()
#else
#  include <unistd.h>  // for getpid()
#endif                 // defined(XP_WIN)

namespace mozilla::dom {

AutoTArray<RefPtr<DocGroup>, 2>* DocGroup::sPendingDocGroups = nullptr;

NS_IMPL_CYCLE_COLLECTION_CLASS(DocGroup)

NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(DocGroup)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mSignalSlotList)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mBrowsingContextGroup)

  for (const MediaSourceURLEntry& entry : tmp->mMediaSourceURLs.Values()) {
    CycleCollectionNoteChild(cb, entry.mMediaSource.get(),
                             "mMediaSourceURLs[].mMediaSource");
    CycleCollectionNoteChild(cb, entry.mOwner.get(),
                             "mMediaSourceURLs[].mOwner");
  }
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END

NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(DocGroup)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mSignalSlotList)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mBrowsingContextGroup)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mMediaSourceURLs)

  // If we still have any documents in this array, they were just unlinked, so
  // clear out our weak pointers to them.
  tmp->mDocuments.Clear();
NS_IMPL_CYCLE_COLLECTION_UNLINK_END

/* static */
already_AddRefed<DocGroup> DocGroup::Create(
    BrowsingContextGroup* aBrowsingContextGroup, const DocGroupKey& aKey) {
  return do_AddRef(new DocGroup(aBrowsingContextGroup, aKey));
}

void DocGroup::AssertMatches(const Document* aDocument) const {
  nsCOMPtr<nsIPrincipal> principal = aDocument->NodePrincipal();

  // Ensure that this DocGroup is correctly origin keyed / non-origin-keyed.
  Maybe<bool> usesOriginAgentCluster =
      mBrowsingContextGroup->UsesOriginAgentCluster(principal);
  MOZ_RELEASE_ASSERT(
      usesOriginAgentCluster.isSome(),
      "Document principal with unknown OriginAgentCluster behaviour");
  MOZ_RELEASE_ASSERT(*usesOriginAgentCluster == mKey.mOriginKeyed,
                     "DocGroup origin keying does not match Principal");

  // Ensure that the origin is as expected. Note that `GetSiteOrigin` can fail
  // after the TLD service is shut down, and we don't want to assert in that
  // case.
  nsresult rv = NS_ERROR_FAILURE;
  nsAutoCString key;
  if (mKey.mOriginKeyed) {
    rv = principal->GetOrigin(key);
  } else {
    rv = principal->GetSiteOrigin(key);
  }
  if (NS_SUCCEEDED(rv)) {
    MOZ_RELEASE_ASSERT(key == mKey.mKey,
                       "DocGroup Key does not match Document");
  }
}

void DocGroup::SetExecutionManager(JSExecutionManager* aManager) {
  mExecutionManager = aManager;
}

mozilla::dom::CustomElementReactionsStack*
DocGroup::CustomElementReactionsStack() {
  MOZ_ASSERT(NS_IsMainThread());
  if (!mReactionsStack) {
    mReactionsStack = new mozilla::dom::CustomElementReactionsStack();
  }

  return mReactionsStack;
}

void DocGroup::AddDocument(Document* aDocument) {
  MOZ_ASSERT(NS_IsMainThread());
  MOZ_ASSERT(!mDocuments.Contains(aDocument));
  MOZ_ASSERT(mBrowsingContextGroup);
  // If the document is loaded as data it may not have a container, in which
  // case it can be difficult to determine the BrowsingContextGroup it's
  // associated with. XSLT can also add the document to the DocGroup before it
  // gets a container in some cases, in which case this will be asserted
  // elsewhere.
  MOZ_ASSERT_IF(
      aDocument->GetBrowsingContext(),
      aDocument->GetBrowsingContext()->Group() == mBrowsingContextGroup);
  mDocuments.AppendElement(aDocument);
}

void DocGroup::RemoveDocument(Document* aDocument) {
  MOZ_ASSERT(NS_IsMainThread());
  MOZ_ASSERT(mDocuments.Contains(aDocument));
  mDocuments.RemoveElement(aDocument);

  if (mDocuments.IsEmpty()) {
    mBrowsingContextGroup = nullptr;
  }
}

DocGroup::DocGroup(BrowsingContextGroup* aBrowsingContextGroup,
                   const DocGroupKey& aKey)
    : mKey(aKey),
      mBrowsingContextGroup(aBrowsingContextGroup),
      mAgentClusterId(nsID::GenerateUUID()) {
  // This method does not add itself to
  // mBrowsingContextGroup->mDocGroups as the caller does it for us.
  MOZ_ASSERT(NS_IsMainThread());
  mArena = new mozilla::dom::DOMArena(aKey.mKey);
}

DocGroup::~DocGroup() {
  MOZ_RELEASE_ASSERT(NS_IsMainThread());
  MOZ_RELEASE_ASSERT(mDocuments.IsEmpty());
}

void DocGroup::SignalSlotChange(HTMLSlotElement& aSlot) {
  MOZ_ASSERT(!mSignalSlotList.Contains(&aSlot));
  mSignalSlotList.AppendElement(&aSlot);

  if (!sPendingDocGroups) {
    // Queue a mutation observer compound microtask.
    nsDOMMutationObserver::QueueMutationObserverMicroTask();
    sPendingDocGroups = new AutoTArray<RefPtr<DocGroup>, 2>;
  }

  sPendingDocGroups->AppendElement(this);
}

nsTArray<RefPtr<HTMLSlotElement>> DocGroup::MoveSignalSlotList() {
  for (const RefPtr<HTMLSlotElement>& slot : mSignalSlotList) {
    slot->RemovedFromSignalSlotList();
  }
  return std::move(mSignalSlotList);
}

bool DocGroup::IsActive() const {
  for (Document* doc : mDocuments) {
    if (doc->IsCurrentActiveDocument()) {
      return true;
    }
  }

  return false;
}

nsresult DocGroup::RegisterMediaSourceURL(nsGlobalWindowInner* aWindow,
                                          MediaSource* aMediaSource,
                                          nsACString& aURL) {
  NS_ENSURE_ARG(aWindow);
  NS_ENSURE_ARG(aMediaSource);

  if (NS_WARN_IF(aWindow->IsDying()) ||
      NS_WARN_IF(aWindow->GetDocGroup() != this)) {
    return NS_ERROR_FAILURE;
  }

  nsCOMPtr<nsIPrincipal> principal = aWindow->PrincipalOrNull();
  if (NS_WARN_IF(!principal)) {
    return NS_ERROR_DOM_SECURITY_ERR;
  }
  nsresult rv = BlobURLProtocolHandler::GenerateURIString(principal, aURL);
  if (NS_WARN_IF(NS_FAILED(rv))) {
    return rv;
  }

  MOZ_ASSERT(!mMediaSourceURLs.Contains(aURL), "URL collision?");
  mMediaSourceURLs.InsertOrUpdate(
      aURL,
      MediaSourceURLEntry{.mMediaSource = aMediaSource, .mOwner = aWindow});

  // Ensure the Window knows about this URL so it can be cleaned up when the
  // Window is destroyed, and can be reported in the memory reporter.
  aWindow->NoteMediaSourceURL(aURL);
  return NS_OK;
}

bool DocGroup::UnregisterMediaSourceURL(const nsACString& aURL,
                                        bool aNotifyWindow) {
  auto removed = mMediaSourceURLs.Extract(aURL);
  if (aNotifyWindow && removed && removed->mOwner) {
    // Remove this MediaSource from the Window which created the URL, removing
    // it from the memory report and ensuring UnregisterMediaSourceURL won't be
    // called when the window is destroyed.
    removed->mOwner->UnnoteMediaSourceURL(aURL);
  }
  return removed.isSome();
}

already_AddRefed<MediaSource> DocGroup::LookupMediaSourceURL(nsIURI* aURI) {
  MOZ_ASSERT(aURI && aURI->SchemeIs(BLOBURI_SCHEME));

  nsAutoCString spec;
  if (NS_WARN_IF(NS_FAILED(aURI->GetSpec(spec)))) {
    return nullptr;
  }
  if (auto entry = mMediaSourceURLs.Lookup(spec)) {
    return do_AddRef(entry->mMediaSource);
  }
  return nullptr;
}

}  // namespace mozilla::dom