#include "store.hpp"

#include <iterator>
#include <sstream>
#include <stdexcept>

#include <components/debug/debuglog.hpp>
#include <components/esm/records.hpp>
#include <components/esm3/esmreader.hpp>
#include <components/esm3/esmwriter.hpp>
#include <components/loadinglistener/loadinglistener.hpp>
#include <components/misc/rng.hpp>

#include <apps/openmw/mwworld/cell.hpp>

namespace
{
    // TODO: Switch to C++23 to get a working version of std::unordered_map::erase
    template <class T, class Id>
    bool eraseFromMap(T& map, const Id& value)
    {
        auto it = map.find(value);
        if (it != map.end())
        {
            map.erase(it);
            return true;
        }
        return false;
    }
}

namespace MWWorld
{
    RecordId::RecordId(const ESM::RefId& id, bool isDeleted)
        : mId(id)
        , mIsDeleted(isDeleted)
    {
    }

    template <typename T>
    IndexedStore<T>::IndexedStore()
    {
    }
    template <typename T>
    typename IndexedStore<T>::iterator IndexedStore<T>::begin() const
    {
        return mStatic.begin();
    }
    template <typename T>
    typename IndexedStore<T>::iterator IndexedStore<T>::end() const
    {
        return mStatic.end();
    }
    template <typename T>
    void IndexedStore<T>::load(ESM::ESMReader& esm)
    {
        T record;
        bool isDeleted = false;

        record.load(esm, isDeleted);
        auto idx = record.mIndex;
        mStatic.insert_or_assign(idx, std::move(record));
    }
    template <typename T>
    int IndexedStore<T>::getSize() const
    {
        return mStatic.size();
    }
    template <typename T>
    void IndexedStore<T>::setUp()
    {
    }
    template <typename T>
    const T* IndexedStore<T>::search(int index) const
    {
        typename Static::const_iterator it = mStatic.find(index);
        if (it != mStatic.end())
            return &(it->second);
        return nullptr;
    }
    template <typename T>
    const T* IndexedStore<T>::find(int index) const
    {
        const T* ptr = search(index);
        if (ptr == nullptr)
        {
            std::stringstream msg;
            msg << T::getRecordType() << " with index " << index << " not found";
            throw std::runtime_error(msg.str());
        }
        return ptr;
    }

    // Need to instantiate these before they're used
    template class IndexedStore<ESM::MagicEffect>;
    template class IndexedStore<ESM::Skill>;

    template <class T, class Id>
    TypedDynamicStore<T, Id>::TypedDynamicStore()
    {
    }

    template <class T, class Id>
    TypedDynamicStore<T, Id>::TypedDynamicStore(const TypedDynamicStore<T, Id>& orig)
        : mStatic(orig.mStatic)
    {
    }

    template <class T, class Id>
    void TypedDynamicStore<T, Id>::clearDynamic()
    {
        // remove the dynamic part of mShared
        assert(mShared.size() >= mStatic.size());
        mShared.erase(mShared.begin() + mStatic.size(), mShared.end());
        mDynamic.clear();
    }

    template <class T, class Id>
    const T* TypedDynamicStore<T, Id>::search(const Id& id) const
    {
        typename Dynamic::const_iterator dit = mDynamic.find(id);
        if (dit != mDynamic.end())
            return &dit->second;

        typename Static::const_iterator it = mStatic.find(id);
        if (it != mStatic.end())
            return &(it->second);

        return nullptr;
    }
    template <class T, class Id>
    const T* TypedDynamicStore<T, Id>::searchStatic(const Id& id) const
    {
        typename Static::const_iterator it = mStatic.find(id);
        if (it != mStatic.end())
            return &(it->second);

        return nullptr;
    }

    template <class T, class Id>
    bool TypedDynamicStore<T, Id>::isDynamic(const Id& id) const
    {
        typename Dynamic::const_iterator dit = mDynamic.find(id);
        return (dit != mDynamic.end());
    }
    template <class T, class Id>
    const T* TypedDynamicStore<T, Id>::searchRandom(const std::string_view prefix, Misc::Rng::Generator& prng) const
    {
        if constexpr (std::is_same_v<Id, ESM::RefId>)
        {
            std::vector<const T*> results;
            std::copy_if(mShared.begin(), mShared.end(), std::back_inserter(results),
                [prefix](const T* item) { return item->mId.startsWith(prefix); });
            if (!results.empty())
                return results[Misc::Rng::rollDice(results.size(), prng)];
            return nullptr;
        }
        else
            throw std::runtime_error("Store<T>::searchRandom is supported only if Id is ESM::RefId");
    }
    template <class T, class Id>
    const T* TypedDynamicStore<T, Id>::find(const Id& id) const
    {
        const T* ptr = search(id);
        if (ptr == nullptr)
        {
            std::stringstream msg;
            if constexpr (!ESM::isESM4Rec(T::sRecordId))
            {
                msg << T::getRecordType();
            }
            else
            {
                msg << "ESM::REC_" << getRecNameString(T::sRecordId).toStringView();
            }
            msg << " '" << id << "' not found";
            throw std::runtime_error(msg.str());
        }
        return ptr;
    }
    template <class T, class Id>
    RecordId TypedDynamicStore<T, Id>::load(ESM::ESMReader& esm)
    {
        T record;
        bool isDeleted = false;
        if constexpr (!ESM::isESM4Rec(T::sRecordId))
        {
            record.load(esm, isDeleted);
        }

        std::pair<typename Static::iterator, bool> inserted = mStatic.insert_or_assign(record.mId, record);
        if (inserted.second)
            mShared.push_back(&inserted.first->second);

        if constexpr (std::is_same_v<Id, ESM::RefId>)
            return RecordId(record.mId, isDeleted);
        else
            return RecordId();
    }

    template <class T, class Id>
    void TypedDynamicStore<T, Id>::setUp()
    {
    }

    template <class T, class Id>
    typename TypedDynamicStore<T, Id>::iterator TypedDynamicStore<T, Id>::begin() const
    {
        return mShared.begin();
    }
    template <class T, class Id>
    typename TypedDynamicStore<T, Id>::iterator TypedDynamicStore<T, Id>::end() const
    {
        return mShared.end();
    }

    template <class T, class Id>
    size_t TypedDynamicStore<T, Id>::getSize() const
    {
        return mShared.size();
    }

    template <class T, class Id>
    int TypedDynamicStore<T, Id>::getDynamicSize() const
    {
        return mDynamic.size();
    }
    template <class T, class Id>
    void TypedDynamicStore<T, Id>::listIdentifier(std::vector<Id>& list) const
    {
        list.reserve(list.size() + getSize());
        typename std::vector<T*>::const_iterator it = mShared.begin();
        for (; it != mShared.end(); ++it)
        {
            list.push_back((*it)->mId);
        }
    }
    template <class T, class Id>
    T* TypedDynamicStore<T, Id>::insert(const T& item, bool overrideOnly)
    {
        if (overrideOnly)
        {
            auto it = mStatic.find(item.mId);
            if (it == mStatic.end())
                return nullptr;
        }
        std::pair<typename Dynamic::iterator, bool> result = mDynamic.insert_or_assign(item.mId, item);
        T* ptr = &result.first->second;
        if (result.second)
            mShared.push_back(ptr);
        return ptr;
    }
    template <class T, class Id>
    T* TypedDynamicStore<T, Id>::insertStatic(const T& item)
    {
        std::pair<typename Static::iterator, bool> result = mStatic.insert_or_assign(item.mId, item);
        T* ptr = &result.first->second;
        if (result.second)
            mShared.push_back(ptr);
        return ptr;
    }
    template <class T, class Id>
    bool TypedDynamicStore<T, Id>::eraseStatic(const Id& id)
    {
        typename Static::iterator it = mStatic.find(id);

        if (it != mStatic.end())
        {
            // delete from the static part of mShared
            typename std::vector<T*>::iterator sharedIter = mShared.begin();
            typename std::vector<T*>::iterator end = sharedIter + mStatic.size();

            while (sharedIter != mShared.end() && sharedIter != end)
            {
                if ((*sharedIter)->mId == id)
                {
                    mShared.erase(sharedIter);
                    break;
                }
                ++sharedIter;
            }
            mStatic.erase(it);
        }

        return true;
    }

    template <class T, class Id>
    bool TypedDynamicStore<T, Id>::erase(const Id& id)
    {
        if (!eraseFromMap(mDynamic, id))
            return false;

        // have to reinit the whole shared part
        assert(mShared.size() >= mStatic.size());
        mShared.erase(mShared.begin() + mStatic.size(), mShared.end());
        for (auto it = mDynamic.begin(); it != mDynamic.end(); ++it)
        {
            mShared.push_back(&it->second);
        }
        return true;
    }
    template <class T, class Id>
    bool TypedDynamicStore<T, Id>::erase(const T& item)
    {
        return erase(item.mId);
    }
    template <class T, class Id>
    void TypedDynamicStore<T, Id>::write(ESM::ESMWriter& writer, Loading::Listener& progress) const
    {
        for (typename Dynamic::const_iterator iter(mDynamic.begin()); iter != mDynamic.end(); ++iter)
        {
            if constexpr (!ESM::isESM4Rec(T::sRecordId))
            {
                writer.startRecord(T::sRecordId);
                iter->second.save(writer);
                writer.endRecord(T::sRecordId);
            }
        }
    }
    template <class T, class Id>
    RecordId TypedDynamicStore<T, Id>::read(ESM::ESMReader& reader, bool overrideOnly)
    {
        T record;
        bool isDeleted = false;
        if constexpr (!ESM::isESM4Rec(T::sRecordId))
        {
            record.load(reader, isDeleted);
        }
        insert(record, overrideOnly);

        if constexpr (std::is_same_v<Id, ESM::RefId>)
            return RecordId(record.mId, isDeleted);
        else
            return RecordId();
    }

    // LandTexture
    //=========================================================================
    Store<ESM::LandTexture>::Store() {}
    const ESM::LandTexture* Store<ESM::LandTexture>::search(size_t index, size_t plugin) const
    {
        assert(plugin < mStatic.size());
        const LandTextureList& ltexl = mStatic[plugin];

        if (index >= ltexl.size())
            return nullptr;
        return &ltexl[index];
    }
    const ESM::LandTexture* Store<ESM::LandTexture>::find(size_t index, size_t plugin) const
    {
        const ESM::LandTexture* ptr = search(index, plugin);
        if (ptr == nullptr)
        {
            const std::string msg = "Land texture with index " + std::to_string(index) + " not found";
            throw std::runtime_error(msg);
        }
        return ptr;
    }

    void Store<ESM::LandTexture>::resize(std::size_t num)
    {
        mStatic.resize(num);
    }

    size_t Store<ESM::LandTexture>::getSize() const
    {
        return mStatic.size();
    }
    size_t Store<ESM::LandTexture>::getSize(size_t plugin) const
    {
        assert(plugin < mStatic.size());
        return mStatic[plugin].size();
    }
    RecordId Store<ESM::LandTexture>::load(ESM::ESMReader& esm)
    {
        ESM::LandTexture lt;
        bool isDeleted = false;

        lt.load(esm, isDeleted);

        // Replace texture for records with given ID and index from all plugins.
        for (unsigned int i = 0; i < mStatic.size(); i++)
        {
            ESM::LandTexture* tex = const_cast<ESM::LandTexture*>(search(lt.mIndex, i));
            if (tex)
            {
                if (tex->mId == lt.mId)
                    tex->mTexture = lt.mTexture;
            }
        }

        LandTextureList& ltexl = mStatic.back();
        if (lt.mIndex + 1 > (int)ltexl.size())
            ltexl.resize(lt.mIndex + 1);

        // Store it
        auto idx = lt.mIndex;
        ltexl[idx] = std::move(lt);

        return RecordId(ltexl[idx].mId, isDeleted);
    }
    Store<ESM::LandTexture>::iterator Store<ESM::LandTexture>::begin(size_t plugin) const
    {
        assert(plugin < mStatic.size());
        return mStatic[plugin].begin();
    }
    Store<ESM::LandTexture>::iterator Store<ESM::LandTexture>::end(size_t plugin) const
    {
        assert(plugin < mStatic.size());
        return mStatic[plugin].end();
    }

    // Land
    //=========================================================================
    Store<ESM::Land>::~Store() {}
    size_t Store<ESM::Land>::getSize() const
    {
        return mStatic.size();
    }
    Store<ESM::Land>::iterator Store<ESM::Land>::begin() const
    {
        return iterator(mStatic.begin());
    }
    Store<ESM::Land>::iterator Store<ESM::Land>::end() const
    {
        return iterator(mStatic.end());
    }
    const ESM::Land* Store<ESM::Land>::search(int x, int y) const
    {
        std::pair<int, int> comp(x, y);
        if (auto it = mStatic.find(comp); it != mStatic.end() && it->mX == x && it->mY == y)
            return &*it;
        return nullptr;
    }
    const ESM::Land* Store<ESM::Land>::find(int x, int y) const
    {
        const ESM::Land* ptr = search(x, y);
        if (ptr == nullptr)
        {
            const std::string msg = "Land at (" + std::to_string(x) + ", " + std::to_string(y) + ") not found";
            throw std::runtime_error(msg);
        }
        return ptr;
    }
    RecordId Store<ESM::Land>::load(ESM::ESMReader& esm)
    {
        ESM::Land land;
        bool isDeleted = false;

        land.load(esm, isDeleted);

        // Same area defined in multiple plugins? -> last plugin wins
        auto it = mStatic.lower_bound(land);
        if (it != mStatic.end() && (std::tie(it->mX, it->mY) == std::tie(land.mX, land.mY)))
        {
            auto nh = mStatic.extract(it);
            nh.value() = std::move(land);
            mStatic.insert(std::move(nh));
        }
        else
            mStatic.insert(it, std::move(land));

        return RecordId(ESM::RefId(), isDeleted);
    }
    void Store<ESM::Land>::setUp()
    {
        // The land is static for given game session, there is no need to refresh it every load.
        if (mBuilt)
            return;

        mBuilt = true;
    }

    // Cell
    //=========================================================================

    const ESM::Cell* Store<ESM::Cell>::search(const ESM::RefId& cellId) const
    {
        auto foundCellIt = mCells.find(cellId);
        if (foundCellIt != mCells.end())
            return &foundCellIt->second;
        return nullptr;
    }

    const ESM::Cell* Store<ESM::Cell>::search(const ESM::Cell& cell) const
    {
        return search(cell.mId);
    }

    // this method *must* be called right after esm3.loadCell()
    void Store<ESM::Cell>::handleMovedCellRefs(ESM::ESMReader& esm, ESM::Cell* cell)
    {
        ESM::CellRef ref;
        ESM::MovedCellRef cMRef;
        bool deleted = false;
        bool moved = false;

        ESM::ESM_Context ctx = esm.getContext();

        // Handling MovedCellRefs, there is no way to do it inside loadcell
        // TODO: verify above comment
        //
        // Get regular moved reference data. Adapted from CellStore::loadRefs. Maybe we can optimize the following
        //  implementation when the oher implementation works as well.
        while (ESM::Cell::getNextRef(esm, ref, deleted, cMRef, moved, ESM::Cell::GetNextRefMode::LoadOnlyMoved))
        {
            if (!moved)
                continue;

            ESM::Cell* cellAlt = const_cast<ESM::Cell*>(searchOrCreate(cMRef.mTarget[0], cMRef.mTarget[1]));

            // Add data required to make reference appear in the correct cell.
            // We should not need to test for duplicates, as this part of the code is pre-cell merge.
            cell->mMovedRefs.push_back(cMRef);

            // But there may be duplicates here!
            ESM::CellRefTracker::iterator iter = std::find_if(
                cellAlt->mLeasedRefs.begin(), cellAlt->mLeasedRefs.end(), ESM::CellRefTrackerPredicate(ref.mRefNum));
            if (iter == cellAlt->mLeasedRefs.end())
                cellAlt->mLeasedRefs.emplace_back(std::move(ref), deleted);
            else
                *iter = std::make_pair(std::move(ref), deleted);

            cMRef.mRefNum.mIndex = 0;
        }

        esm.restoreContext(ctx);
    }
    const ESM::Cell* Store<ESM::Cell>::search(std::string_view name) const
    {
        DynamicInt::const_iterator it = mInt.find(name);
        if (it != mInt.end())
        {
            return it->second;
        }

        DynamicInt::const_iterator dit = mDynamicInt.find(name);
        if (dit != mDynamicInt.end())
        {
            return dit->second;
        }

        return nullptr;
    }
    const ESM::Cell* Store<ESM::Cell>::search(int x, int y) const
    {
        std::pair<int, int> key(x, y);
        DynamicExt::const_iterator it = mExt.find(key);
        if (it != mExt.end())
            return it->second;

        DynamicExt::const_iterator dit = mDynamicExt.find(key);
        if (dit != mDynamicExt.end())
            return dit->second;

        return nullptr;
    }
    const ESM::Cell* Store<ESM::Cell>::searchStatic(int x, int y) const
    {
        DynamicExt::const_iterator it = mExt.find(std::make_pair(x, y));
        if (it != mExt.end())
            return (it->second);
        return nullptr;
    }
    const ESM::Cell* Store<ESM::Cell>::searchOrCreate(int x, int y)
    {
        std::pair<int, int> key(x, y);
        DynamicExt::const_iterator it = mExt.find(key);
        if (it != mExt.end())
            return (it->second);

        DynamicExt::const_iterator dit = mDynamicExt.find(key);
        if (dit != mDynamicExt.end())
            return dit->second;

        ESM::Cell newCell;
        newCell.mData.mX = x;
        newCell.mData.mY = y;
        newCell.mData.mFlags = ESM::Cell::HasWater;
        newCell.mAmbi.mAmbient = 0;
        newCell.mAmbi.mSunlight = 0;
        newCell.mAmbi.mFog = 0;
        newCell.mAmbi.mFogDensity = 0;
        newCell.updateId();

        ESM::Cell* newCellInserted = &mCells.insert(std::make_pair(newCell.mId, newCell)).first->second;

        return mExt.insert(std::make_pair(key, newCellInserted)).first->second;
    }
    const ESM::Cell* Store<ESM::Cell>::find(const ESM::RefId& id) const
    {
        const ESM::Cell* ptr = search(id);
        if (ptr == nullptr)
        {
            const std::string msg = "Cell " + id.toDebugString() + " not found";
            throw std::runtime_error(msg);
        }
        return ptr;
    }
    const ESM::Cell* Store<ESM::Cell>::find(std::string_view id) const
    {
        const ESM::Cell* ptr = search(id);
        if (ptr == nullptr)
        {
            const std::string msg = "Cell '" + std::string(id) + "' not found";
            throw std::runtime_error(msg);
        }
        return ptr;
    }
    const ESM::Cell* Store<ESM::Cell>::find(int x, int y) const
    {
        const ESM::Cell* ptr = search(x, y);
        if (ptr == nullptr)
        {
            const std::string msg = "Exterior at (" + std::to_string(x) + ", " + std::to_string(y) + ") not found";
            throw std::runtime_error(msg);
        }
        return ptr;
    }
    void Store<ESM::Cell>::clearDynamic()
    {
        setUp();
    }

    void Store<ESM::Cell>::setUp()
    {
        mSharedInt.clear();
        mSharedInt.reserve(mInt.size());
        for (auto& [_, cell] : mInt)
            mSharedInt.push_back(cell);

        mSharedExt.clear();
        mSharedExt.reserve(mExt.size());
        for (auto& [_, cell] : mExt)
            mSharedExt.push_back(cell);
    }
    RecordId Store<ESM::Cell>::load(ESM::ESMReader& esm)
    {
        // Don't automatically assume that a new cell must be spawned. Multiple plugins write to the same cell,
        //  and we merge all this data into one Cell object. However, we can't simply search for the cell id,
        //  as many exterior cells do not have a name. Instead, we need to search by (x,y) coordinates - and they
        //  are not available until both cells have been loaded at least partially!

        // All cells have a name record, even nameless exterior cells.
        ESM::Cell* emplacedCell = nullptr;
        bool isDeleted = false;

        {
            ESM::Cell cellToLoad;
            cellToLoad.loadNameAndData(esm, isDeleted);
            emplacedCell = &mCells.insert(std::make_pair(cellToLoad.mId, cellToLoad)).first->second;
        }
        ESM::Cell& cell = *emplacedCell;
        // Load the (x,y) coordinates of the cell, if it is an exterior cell,
        // so we can find the cell we need to merge with
        if (cell.mData.mFlags & ESM::Cell::Interior)
        {
            // Store interior cell by name, try to merge with existing parent data.
            ESM::Cell* oldcell = const_cast<ESM::Cell*>(search(cell.mName));
            if (oldcell)
            {
                // merge new cell into old cell
                // push the new references on the list of references to manage (saveContext = true)
                oldcell->mData = cell.mData;
                oldcell->mName
                    = cell.mName; // merge name just to be sure (ID will be the same, but case could have been changed)
                oldcell->loadCell(esm, true);
            }
            else
            {
                // spawn a new cell
                cell.loadCell(esm, true);

                mInt[cell.mName] = &cell;
            }
        }
        else
        {
            // Store exterior cells by grid position, try to merge with existing parent data.
            ESM::Cell* oldcell = const_cast<ESM::Cell*>(search(cell.getGridX(), cell.getGridY()));
            if (oldcell)
            {
                // merge new cell into old cell
                oldcell->mData = cell.mData;
                oldcell->mName = cell.mName;
                oldcell->loadCell(esm, false);

                // handle moved ref (MVRF) subrecords
                handleMovedCellRefs(esm, &cell);

                // push the new references on the list of references to manage
                oldcell->postLoad(esm);

                // merge lists of leased references, use newer data in case of conflict
                for (ESM::MovedCellRefTracker::const_iterator it = cell.mMovedRefs.begin(); it != cell.mMovedRefs.end();
                     ++it)
                {
                    // remove reference from current leased ref tracker and add it to new cell
                    ESM::MovedCellRefTracker::iterator itold
                        = std::find(oldcell->mMovedRefs.begin(), oldcell->mMovedRefs.end(), it->mRefNum);
                    if (itold != oldcell->mMovedRefs.end())
                    {
                        if (it->mTarget[0] != itold->mTarget[0] || it->mTarget[1] != itold->mTarget[1])
                        {
                            ESM::Cell* wipecell = const_cast<ESM::Cell*>(search(itold->mTarget[0], itold->mTarget[1]));
                            ESM::CellRefTracker::iterator it_lease = std::find_if(wipecell->mLeasedRefs.begin(),
                                wipecell->mLeasedRefs.end(), ESM::CellRefTrackerPredicate(it->mRefNum));
                            if (it_lease != wipecell->mLeasedRefs.end())
                                wipecell->mLeasedRefs.erase(it_lease);
                            else
                                Log(Debug::Error) << "Error: can't find " << it->mRefNum.mIndex << " "
                                                  << it->mRefNum.mContentFile << " in leasedRefs";
                        }
                        *itold = *it;
                    }
                    else
                        oldcell->mMovedRefs.push_back(*it);
                }

                // We don't need to merge mLeasedRefs of cell / oldcell. This list is filled when another cell moves a
                // reference to this cell, so the list for the new cell should be empty. The list for oldcell,
                // however, could have leased refs in it and so should be kept.
            }
            else
            {
                // spawn a new cell
                emplacedCell->loadCell(esm, false);

                // handle moved ref (MVRF) subrecords
                handleMovedCellRefs(esm, emplacedCell);

                // push the new references on the list of references to manage
                emplacedCell->postLoad(esm);

                mExt[std::make_pair(cell.mData.mX, cell.mData.mY)] = &cell;
            }
        }

        return RecordId(cell.mId, isDeleted);
    }
    Store<ESM::Cell>::iterator Store<ESM::Cell>::intBegin() const
    {
        return iterator(mSharedInt.begin());
    }
    Store<ESM::Cell>::iterator Store<ESM::Cell>::intEnd() const
    {
        return iterator(mSharedInt.end());
    }
    Store<ESM::Cell>::iterator Store<ESM::Cell>::extBegin() const
    {
        return iterator(mSharedExt.begin());
    }
    Store<ESM::Cell>::iterator Store<ESM::Cell>::extEnd() const
    {
        return iterator(mSharedExt.end());
    }
    const ESM::Cell* Store<ESM::Cell>::searchExtByName(std::string_view name) const
    {
        const ESM::Cell* cell = nullptr;
        for (const ESM::Cell* sharedCell : mSharedExt)
        {
            if (Misc::StringUtils::ciEqual(sharedCell->mName, name))
            {
                if (cell == nullptr || (sharedCell->mData.mX > cell->mData.mX)
                    || (sharedCell->mData.mX == cell->mData.mX && sharedCell->mData.mY > cell->mData.mY))
                {
                    cell = sharedCell;
                }
            }
        }
        return cell;
    }
    const ESM::Cell* Store<ESM::Cell>::searchExtByRegion(const ESM::RefId& id) const
    {
        const ESM::Cell* cell = nullptr;
        for (const ESM::Cell* sharedCell : mSharedExt)
        {
            if (sharedCell->mRegion == id)
            {
                if (cell == nullptr || (sharedCell->mData.mX > cell->mData.mX)
                    || (sharedCell->mData.mX == cell->mData.mX && sharedCell->mData.mY > cell->mData.mY))
                {
                    cell = sharedCell;
                }
            }
        }
        return cell;
    }
    size_t Store<ESM::Cell>::getSize() const
    {
        return mSharedInt.size() + mSharedExt.size();
    }
    size_t Store<ESM::Cell>::getExtSize() const
    {
        return mSharedExt.size();
    }
    size_t Store<ESM::Cell>::getIntSize() const
    {
        return mSharedInt.size();
    }
    void Store<ESM::Cell>::listIdentifier(std::vector<ESM::RefId>& list) const
    {
        list.reserve(list.size() + mSharedInt.size());

        for (const ESM::Cell* sharedCell : mSharedInt)
        {
            list.push_back(ESM::RefId::stringRefId(sharedCell->mName));
        }
    }
    ESM::Cell* Store<ESM::Cell>::insert(const ESM::Cell& cell)
    {
        if (search(cell) != nullptr)
        {
            const std::string cellType = (cell.isExterior()) ? "exterior" : "interior";
            throw std::runtime_error("Failed to create " + cellType + " cell");
        }
        ESM::Cell* insertedCell = &mCells.emplace(cell.mId, cell).first->second;
        if (cell.isExterior())
        {
            std::pair<int, int> key(cell.getGridX(), cell.getGridY());

            // duplicate insertions are avoided by search(ESM::Cell &)
            DynamicExt::iterator result = mDynamicExt.emplace(key, insertedCell).first;
            mSharedExt.push_back(result->second);
            return result->second;
        }
        else
        {
            // duplicate insertions are avoided by search(ESM::Cell &)
            DynamicInt::iterator result = mDynamicInt.emplace(cell.mName, insertedCell).first;
            mSharedInt.push_back(result->second);
            return result->second;
        }
    }
    bool Store<ESM::Cell>::erase(const ESM::Cell& cell)
    {
        if (cell.isExterior())
        {
            return erase(cell.getGridX(), cell.getGridY());
        }
        return erase(cell.mName);
    }
    bool Store<ESM::Cell>::erase(std::string_view name)
    {
        auto it = mDynamicInt.find(name);

        if (it == mDynamicInt.end())
        {
            return false;
        }
        mDynamicInt.erase(it);
        mSharedInt.erase(mSharedInt.begin() + mSharedInt.size(), mSharedInt.end());

        for (it = mDynamicInt.begin(); it != mDynamicInt.end(); ++it)
        {
            mSharedInt.push_back(it->second);
        }

        return true;
    }
    bool Store<ESM::Cell>::erase(int x, int y)
    {
        std::pair<int, int> key(x, y);
        DynamicExt::iterator it = mDynamicExt.find(key);

        if (it == mDynamicExt.end())
        {
            return false;
        }
        mDynamicExt.erase(it);
        mSharedExt.erase(mSharedExt.begin() + mSharedExt.size(), mSharedExt.end());

        for (it = mDynamicExt.begin(); it != mDynamicExt.end(); ++it)
        {
            mSharedExt.push_back(it->second);
        }

        return true;
    }

    // Pathgrid
    //=========================================================================

    Store<ESM::Pathgrid>::Store()
        : mCells(nullptr)
    {
    }

    void Store<ESM::Pathgrid>::setCells(Store<ESM::Cell>& cells)
    {
        mCells = &cells;
    }
    RecordId Store<ESM::Pathgrid>::load(ESM::ESMReader& esm)
    {
        ESM::Pathgrid pathgrid;
        bool isDeleted = false;

        pathgrid.load(esm, isDeleted);

        // Unfortunately the Pathgrid record model does not specify whether the pathgrid belongs to an interior or
        // exterior cell. For interior cells, mCell is the cell name, but for exterior cells it is either the cell name
        // or if that doesn't exist, the cell's region name. mX and mY will be (0,0) for interior cells, but there is
        // also an exterior cell with the coordinates of (0,0), so that doesn't help. Check whether mCell is an interior
        // cell. This isn't perfect, will break if a Region with the same name as an interior cell is created. A proper
        // fix should be made for future versions of the file format.
        bool interior = pathgrid.mData.mX == 0 && pathgrid.mData.mY == 0
            && mCells->search(pathgrid.mCell.getRefIdString()) != nullptr;

        ESM::RefId cell
            = interior ? pathgrid.mCell : ESM::RefId::esm3ExteriorCell(pathgrid.mData.mX, pathgrid.mData.mY);
        // deal with mods that have empty pathgrid records (Issue #6209)
        // we assume that these records are empty on purpose (i.e. to remove old pathgrid on an updated cell)
        if (isDeleted || pathgrid.mPoints.empty() || pathgrid.mEdges.empty())
        {
            mStatic.erase(cell);

            return RecordId(ESM::RefId(), isDeleted);
        }

        // Try to overwrite existing record
        auto ret = mStatic.emplace(cell, pathgrid);
        if (!ret.second)
            ret.first->second = pathgrid;

        return RecordId(ESM::RefId(), isDeleted);
    }
    size_t Store<ESM::Pathgrid>::getSize() const
    {
        return mStatic.size();
    }
    void Store<ESM::Pathgrid>::setUp() {}
    const ESM::Pathgrid* Store<ESM::Pathgrid>::search(const ESM::RefId& name) const
    {
        auto it = mStatic.find(name);
        if (it != mStatic.end())
            return &(it->second);
        return nullptr;
    }
    const ESM::Pathgrid* Store<ESM::Pathgrid>::find(const ESM::RefId& name) const
    {
        const ESM::Pathgrid* pathgrid = search(name);
        if (pathgrid == nullptr)
            throw std::runtime_error("Pathgrid in cell " + name.toDebugString() + " is not found");
        return pathgrid;
    }
    const ESM::Pathgrid* Store<ESM::Pathgrid>::search(const ESM::Cell& cell) const
    {
        return search(cell.mId);
    }
    const ESM::Pathgrid* Store<ESM::Pathgrid>::search(const MWWorld::Cell& cellVariant) const
    {
        return ESM::visit(ESM::VisitOverload{
                              [&](const ESM::Cell& cell) { return search(cell); },
                              [&](const ESM4::Cell& cell) -> const ESM::Pathgrid* { return nullptr; },
                          },
            cellVariant);
    }
    const ESM::Pathgrid* Store<ESM::Pathgrid>::find(const ESM::Cell& cell) const
    {
        return find(cell.mId);
    }

    // Skill
    //=========================================================================

    Store<ESM::Skill>::Store() {}

    // Game Settings
    //=========================================================================

    const ESM::GameSetting* Store<ESM::GameSetting>::search(const ESM::RefId& id) const
    {
        return TypedDynamicStore::search(id);
    }

    const ESM::GameSetting* Store<ESM::GameSetting>::find(std::string_view id) const
    {
        return TypedDynamicStore::find(ESM::RefId::stringRefId(id));
    }

    const ESM::GameSetting* Store<ESM::GameSetting>::search(std::string_view id) const
    {
        return TypedDynamicStore::search(ESM::RefId::stringRefId(id));
    }

    // Magic effect
    //=========================================================================
    Store<ESM::MagicEffect>::Store() {}

    // Attribute
    //=========================================================================

    Store<ESM::Attribute>::Store()
    {
        mStatic.reserve(ESM::Attribute::Length);
    }
    const ESM::Attribute* Store<ESM::Attribute>::search(size_t index) const
    {
        if (index >= mStatic.size())
        {
            return nullptr;
        }
        return &mStatic[index];
    }

    const ESM::Attribute* Store<ESM::Attribute>::find(size_t index) const
    {
        const ESM::Attribute* ptr = search(index);
        if (ptr == nullptr)
        {
            const std::string msg = "Attribute with index " + std::to_string(index) + " not found";
            throw std::runtime_error(msg);
        }
        return ptr;
    }
    void Store<ESM::Attribute>::setUp()
    {
        for (int i = 0; i < ESM::Attribute::Length; ++i)
        {
            ESM::Attribute newAttribute;
            newAttribute.mId = ESM::Attribute::sAttributeIds[i];
            newAttribute.mName = ESM::Attribute::sGmstAttributeIds[i];
            newAttribute.mDescription = ESM::Attribute::sGmstAttributeDescIds[i];
            mStatic.push_back(newAttribute);
        }
    }
    size_t Store<ESM::Attribute>::getSize() const
    {
        return mStatic.size();
    }
    Store<ESM::Attribute>::iterator Store<ESM::Attribute>::begin() const
    {
        return mStatic.begin();
    }
    Store<ESM::Attribute>::iterator Store<ESM::Attribute>::end() const
    {
        return mStatic.end();
    }

    // Dialogue
    //=========================================================================

    Store<ESM::Dialogue>::Store()
        : mKeywordSearchModFlag(true)
    {
    }

    void Store<ESM::Dialogue>::setUp()
    {
        // DialInfos marked as deleted are kept during the loading phase, so that the linked list
        // structure is kept intact for inserting further INFOs. Delete them now that loading is done.
        for (auto& [_, dial] : mStatic)
            dial.setUp();

        mShared.clear();
        mShared.reserve(mStatic.size());
        for (auto& [_, dial] : mStatic)
            mShared.push_back(&dial);
        // TODO: verify and document this inconsistent behaviour
        // TODO: if we require this behaviour, maybe we should move it to the place that requires it
        std::sort(mShared.begin(), mShared.end(),
            [](const ESM::Dialogue* l, const ESM::Dialogue* r) -> bool { return l->mId < r->mId; });

        mKeywordSearchModFlag = true;
    }

    const ESM::Dialogue* Store<ESM::Dialogue>::search(const ESM::RefId& id) const
    {
        typename Static::const_iterator it = mStatic.find(id);
        if (it != mStatic.end())
            return &(it->second);

        return nullptr;
    }

    const ESM::Dialogue* Store<ESM::Dialogue>::find(const ESM::RefId& id) const
    {
        const ESM::Dialogue* ptr = search(id);
        if (ptr == nullptr)
        {
            std::stringstream msg;
            msg << ESM::Dialogue::getRecordType() << " '" << id << "' not found";
            throw std::runtime_error(msg.str());
        }
        return ptr;
    }

    typename Store<ESM::Dialogue>::iterator Store<ESM::Dialogue>::begin() const
    {
        return mShared.begin();
    }

    typename Store<ESM::Dialogue>::iterator Store<ESM::Dialogue>::end() const
    {
        return mShared.end();
    }

    size_t Store<ESM::Dialogue>::getSize() const
    {
        return mShared.size();
    }

    inline RecordId Store<ESM::Dialogue>::load(ESM::ESMReader& esm)
    {
        // The original letter case of a dialogue ID is saved, because it's printed
        ESM::Dialogue dialogue;
        bool isDeleted = false;

        dialogue.loadId(esm);

        Static::iterator found = mStatic.find(dialogue.mId);
        if (found == mStatic.end())
        {
            dialogue.loadData(esm, isDeleted);
            mStatic.emplace(dialogue.mId, dialogue);
        }
        else
        {
            found->second.loadData(esm, isDeleted);
            dialogue.mId = found->second.mId;
        }

        mKeywordSearchModFlag = true;

        return RecordId(dialogue.mId, isDeleted);
    }

    bool Store<ESM::Dialogue>::eraseStatic(const ESM::RefId& id)
    {
        if (eraseFromMap(mStatic, id))
            mKeywordSearchModFlag = true;

        return true;
    }

    void Store<ESM::Dialogue>::listIdentifier(std::vector<ESM::RefId>& list) const
    {
        list.reserve(list.size() + getSize());
        for (const auto& dialogue : mShared)
            list.push_back(dialogue->mId);
    }

    const MWDialogue::KeywordSearch<std::string, int>& Store<ESM::Dialogue>::getDialogIdKeywordSearch() const
    {
        if (mKeywordSearchModFlag)
        {
            mKeywordSearch.clear();

            std::vector<std::string> keywordList;
            keywordList.reserve(getSize());
            for (const auto& it : *this)
                keywordList.push_back(Misc::StringUtils::lowerCase(it.mId.getRefIdString()));
            sort(keywordList.begin(), keywordList.end());

            for (const auto& it : keywordList)
                mKeywordSearch.seed(it, 0 /*unused*/);

            mKeywordSearchModFlag = false;
        }

        return mKeywordSearch;
    }

    // ESM4 Cell
    //=========================================================================

    const ESM4::Cell* Store<ESM4::Cell>::searchCellName(std::string_view cellName) const
    {
        const auto foundCell = mCellNameIndex.find(cellName);
        if (foundCell == mCellNameIndex.end())
            return nullptr;
        return foundCell->second;
    }

    ESM4::Cell* Store<ESM4::Cell>::insert(const ESM4::Cell& item, bool overrideOnly)
    {
        auto cellPtr = TypedDynamicStore<ESM4::Cell>::insert(item, overrideOnly);
        mCellNameIndex[cellPtr->mEditorId] = cellPtr;
        return cellPtr;
    }

    ESM4::Cell* Store<ESM4::Cell>::insertStatic(const ESM4::Cell& item)
    {
        auto cellPtr = TypedDynamicStore<ESM4::Cell>::insertStatic(item);
        mCellNameIndex[cellPtr->mEditorId] = cellPtr;
        return cellPtr;
    }
}

template class MWWorld::TypedDynamicStore<ESM::Activator>;
template class MWWorld::TypedDynamicStore<ESM::Apparatus>;
template class MWWorld::TypedDynamicStore<ESM::Armor>;
// template class MWWorld::Store<ESM::Attribute>;
template class MWWorld::TypedDynamicStore<ESM::BirthSign>;
template class MWWorld::TypedDynamicStore<ESM::BodyPart>;
template class MWWorld::TypedDynamicStore<ESM::Book>;
// template class MWWorld::Store<ESM::Cell>;
template class MWWorld::TypedDynamicStore<ESM::Class>;
template class MWWorld::TypedDynamicStore<ESM::Clothing>;
template class MWWorld::TypedDynamicStore<ESM::Container>;
template class MWWorld::TypedDynamicStore<ESM::Creature>;
template class MWWorld::TypedDynamicStore<ESM::CreatureLevList>;
// template class MWWorld::Store<ESM::Dialogue>;
template class MWWorld::TypedDynamicStore<ESM::Door>;
template class MWWorld::TypedDynamicStore<ESM::Enchantment>;
template class MWWorld::TypedDynamicStore<ESM::Faction>;
template class MWWorld::TypedDynamicStore<ESM::GameSetting>;
template class MWWorld::TypedDynamicStore<ESM::Global>;
template class MWWorld::TypedDynamicStore<ESM::Ingredient>;
template class MWWorld::TypedDynamicStore<ESM::ItemLevList>;
// template class MWWorld::Store<ESM::Land>;
// template class MWWorld::Store<ESM::LandTexture>;
template class MWWorld::TypedDynamicStore<ESM::Light>;
template class MWWorld::TypedDynamicStore<ESM::Lockpick>;
// template class MWWorld::Store<ESM::MagicEffect>;
template class MWWorld::TypedDynamicStore<ESM::Miscellaneous>;
template class MWWorld::TypedDynamicStore<ESM::NPC>;
// template class MWWorld::Store<ESM::Pathgrid>;
template class MWWorld::TypedDynamicStore<ESM::Potion>;
template class MWWorld::TypedDynamicStore<ESM::Probe>;
template class MWWorld::TypedDynamicStore<ESM::Race>;
template class MWWorld::TypedDynamicStore<ESM::Region>;
template class MWWorld::TypedDynamicStore<ESM::Repair>;
template class MWWorld::TypedDynamicStore<ESM::Script>;
// template class MWWorld::Store<ESM::Skill>;
template class MWWorld::TypedDynamicStore<ESM::Sound>;
template class MWWorld::TypedDynamicStore<ESM::SoundGenerator>;
template class MWWorld::TypedDynamicStore<ESM::Spell>;
template class MWWorld::TypedDynamicStore<ESM::StartScript>;
template class MWWorld::TypedDynamicStore<ESM::Static>;
template class MWWorld::TypedDynamicStore<ESM::Weapon>;

template class MWWorld::TypedDynamicStore<ESM4::Activator>;
template class MWWorld::TypedDynamicStore<ESM4::Potion>;
template class MWWorld::TypedDynamicStore<ESM4::Ammunition>;
template class MWWorld::TypedDynamicStore<ESM4::Armor>;
template class MWWorld::TypedDynamicStore<ESM4::Book>;
template class MWWorld::TypedDynamicStore<ESM4::Clothing>;
template class MWWorld::TypedDynamicStore<ESM4::Container>;
template class MWWorld::TypedDynamicStore<ESM4::Door>;
template class MWWorld::TypedDynamicStore<ESM4::Ingredient>;
template class MWWorld::TypedDynamicStore<ESM4::MiscItem>;
template class MWWorld::TypedDynamicStore<ESM4::Static>;
template class MWWorld::TypedDynamicStore<ESM4::Light>;
template class MWWorld::TypedDynamicStore<ESM4::Reference, ESM::FormId>;
template class MWWorld::TypedDynamicStore<ESM4::Cell>;
template class MWWorld::TypedDynamicStore<ESM4::Weapon>;
