/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* 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 "HighlightRegistry.h"

#include "Document.h"
#include "Highlight.h"
#include "PresShell.h"
#include "mozilla/CompactPair.h"
#include "mozilla/ErrorResult.h"
#include "mozilla/dom/HighlightBinding.h"
#include "nsAtom.h"
#include "nsCycleCollectionParticipant.h"
#include "nsFrameSelection.h"

namespace mozilla::dom {

NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE_CLASS(HighlightRegistry)

NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(HighlightRegistry)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mDocument)
  for (auto const& iter : tmp->mHighlightsOrdered) {
    iter.second()->RemoveFromHighlightRegistry(*tmp, *iter.first());
  }
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mHighlightsOrdered)
  NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
NS_IMPL_CYCLE_COLLECTION_UNLINK_END

NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(HighlightRegistry)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDocument)
  for (size_t i = 0; i < tmp->mHighlightsOrdered.Length(); ++i) {
    NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mHighlightsOrdered[i].second())
  }
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END

NS_IMPL_CYCLE_COLLECTING_ADDREF(HighlightRegistry)
NS_IMPL_CYCLE_COLLECTING_RELEASE(HighlightRegistry)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(HighlightRegistry)
  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
  NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END

HighlightRegistry::HighlightRegistry(Document* aDocument)
    : mDocument(aDocument) {}

HighlightRegistry::~HighlightRegistry() {
  for (auto const& iter : mHighlightsOrdered) {
    iter.second()->RemoveFromHighlightRegistry(*this, *iter.first());
  }
}

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

void HighlightRegistry::MaybeAddRangeToHighlightSelection(
    AbstractRange& aRange, Highlight& aHighlight) {
  RefPtr<nsFrameSelection> frameSelection = GetFrameSelection();
  if (!frameSelection) {
    return;
  }
  MOZ_ASSERT(frameSelection->GetPresShell());
  if (!frameSelection->GetPresShell()->GetDocument() ||
      frameSelection->GetPresShell()->GetDocument() !=
          aRange.GetComposedDocOfContainers()) {
    // ranges that belong to a different document must not be added.
    return;
  }
  for (auto const& iter : mHighlightsOrdered) {
    if (iter.second() != &aHighlight) {
      continue;
    }

    const RefPtr<nsAtom> highlightName = iter.first();
    frameSelection->AddHighlightSelectionRange(highlightName, aHighlight,
                                               aRange);
  }
}

void HighlightRegistry::MaybeRemoveRangeFromHighlightSelection(
    AbstractRange& aRange, Highlight& aHighlight) {
  RefPtr<nsFrameSelection> frameSelection = GetFrameSelection();
  if (!frameSelection) {
    return;
  }
  MOZ_ASSERT(frameSelection->GetPresShell());

  for (auto const& iter : mHighlightsOrdered) {
    if (iter.second() != &aHighlight) {
      continue;
    }

    const RefPtr<nsAtom> highlightName = iter.first();
    frameSelection->RemoveHighlightSelectionRange(highlightName, aRange);
  }
}

void HighlightRegistry::RemoveHighlightSelection(Highlight& aHighlight) {
  RefPtr<nsFrameSelection> frameSelection = GetFrameSelection();
  if (!frameSelection) {
    return;
  }
  for (auto const& iter : mHighlightsOrdered) {
    if (iter.second() != &aHighlight) {
      continue;
    }

    const RefPtr<nsAtom> highlightName = iter.first();
    frameSelection->RemoveHighlightSelection(highlightName);
  }
}

void HighlightRegistry::RepaintHighlightSelection(Highlight& aHighlight) {
  RefPtr<nsFrameSelection> frameSelection = GetFrameSelection();
  if (!frameSelection) {
    return;
  }
  for (auto const& iter : mHighlightsOrdered) {
    if (iter.second() != &aHighlight) {
      continue;
    }

    const RefPtr<nsAtom> highlightName = iter.first();
    frameSelection->RepaintHighlightSelection(highlightName);
  }
}

void HighlightRegistry::AddHighlightSelectionsToFrameSelection() {
  if (mHighlightsOrdered.IsEmpty()) {
    return;
  }
  RefPtr<nsFrameSelection> frameSelection = GetFrameSelection();
  if (!frameSelection) {
    return;
  }
  for (auto const& iter : mHighlightsOrdered) {
    RefPtr<nsAtom> highlightName = iter.first();
    RefPtr<Highlight> highlight = iter.second();
    frameSelection->AddHighlightSelection(highlightName, *highlight);
  }
}

HighlightRegistry* HighlightRegistry::Set(const nsAString& aKey,
                                          Highlight& aValue, ErrorResult& aRv) {
  // manually check if the highlight `aKey` is already registered to be able to
  // provide a fast path later that avoids calling `std::find_if()`.
  const bool highlightAlreadyPresent =
      HighlightRegistry_Binding::MaplikeHelpers::Has(this, aKey, aRv);
  if (aRv.Failed()) {
    return this;
  }
  HighlightRegistry_Binding::MaplikeHelpers::Set(this, aKey, aValue, aRv);
  if (aRv.Failed()) {
    return this;
  }
  RefPtr<nsFrameSelection> frameSelection = GetFrameSelection();
  RefPtr<nsAtom> highlightNameAtom = NS_AtomizeMainThread(aKey);
  if (highlightAlreadyPresent) {
    // If the highlight named `aKey` was present before, replace its value.
    auto foundIter =
        std::find_if(mHighlightsOrdered.begin(), mHighlightsOrdered.end(),
                     [&highlightNameAtom](auto const& aElm) {
                       return aElm.first() == highlightNameAtom;
                     });
    MOZ_ASSERT(foundIter != mHighlightsOrdered.end(),
               "webIDL maplike and DOM mirror are not in sync");
    foundIter->second()->RemoveFromHighlightRegistry(*this, *highlightNameAtom);
    if (frameSelection) {
      frameSelection->RemoveHighlightSelection(highlightNameAtom);
    }
    foundIter->second() = &aValue;
  } else {
    mHighlightsOrdered.AppendElement(
        CompactPair<RefPtr<nsAtom>, RefPtr<Highlight>>(highlightNameAtom,
                                                       &aValue));
  }
  aValue.AddToHighlightRegistry(*this, *highlightNameAtom);
  if (frameSelection) {
    frameSelection->AddHighlightSelection(highlightNameAtom, aValue);
  }
  return this;
}

void HighlightRegistry::Clear(ErrorResult& aRv) {
  HighlightRegistry_Binding::MaplikeHelpers::Clear(this, aRv);
  if (aRv.Failed()) {
    return;
  }
  auto frameSelection = GetFrameSelection();
  AutoFrameSelectionBatcher batcher(__FUNCTION__);
  batcher.AddFrameSelection(frameSelection);
  for (auto const& iter : mHighlightsOrdered) {
    const RefPtr<nsAtom>& highlightName = iter.first();
    const RefPtr<Highlight>& highlight = iter.second();
    highlight->RemoveFromHighlightRegistry(*this, *highlightName);
    if (frameSelection) {
      // The selection batcher makes sure that no script is run in this call.
      // However, `nsFrameSelection::RemoveHighlightSelection` is marked
      // `MOZ_CAN_RUN_SCRIPT`, therefore `MOZ_KnownLive` is needed regardless.
      frameSelection->RemoveHighlightSelection(MOZ_KnownLive(highlightName));
    }
  }

  mHighlightsOrdered.Clear();
}

bool HighlightRegistry::Delete(const nsAString& aKey, ErrorResult& aRv) {
  if (!HighlightRegistry_Binding::MaplikeHelpers::Delete(this, aKey, aRv)) {
    return false;
  }
  RefPtr<nsAtom> highlightNameAtom = NS_AtomizeMainThread(aKey);
  auto foundIter =
      std::find_if(mHighlightsOrdered.cbegin(), mHighlightsOrdered.cend(),
                   [&highlightNameAtom](auto const& aElm) {
                     return aElm.first() == highlightNameAtom;
                   });
  MOZ_ASSERT(foundIter != mHighlightsOrdered.cend(),
             "HighlightRegistry: maplike and internal data are out of sync!");

  RefPtr<Highlight> highlight = foundIter->second();
  mHighlightsOrdered.RemoveElementAt(foundIter);

  if (auto frameSelection = GetFrameSelection()) {
    frameSelection->RemoveHighlightSelection(highlightNameAtom);
  }
  highlight->RemoveFromHighlightRegistry(*this, *highlightNameAtom);
  return true;
}

RefPtr<nsFrameSelection> HighlightRegistry::GetFrameSelection() {
  return RefPtr<nsFrameSelection>(
      mDocument->GetPresShell() ? mDocument->GetPresShell()->FrameSelection()
                                : nullptr);
}

}  // namespace mozilla::dom