#pragma once

#include <XCEngine/Core/Types.h>

#include "engine/Runtime/Rendering/Picking/ObjectIdCodec.h"

#include <mutex>
#include <unordered_map>

namespace XCEngine {
namespace Rendering {

class RenderObjectIdRegistry {
public:
    static RenderObjectIdRegistry& Get();

    RenderObjectIdRegistry(const RenderObjectIdRegistry&) = delete;
    RenderObjectIdRegistry& operator=(const RenderObjectIdRegistry&) = delete;

    RenderObjectId GetOrAllocateRenderObjectId(Core::uint64 runtimeObjectId);
    bool TryGetRenderObjectId(
        Core::uint64 runtimeObjectId,
        RenderObjectId& outRenderObjectId) const;
    bool TryResolveRuntimeObjectId(
        RenderObjectId renderObjectId,
        Core::uint64& outRuntimeObjectId) const;
    Core::uint64 ResolveRuntimeObjectId(RenderObjectId renderObjectId) const;

    void Reset();
    Core::uint64 GetGeneration() const;

private:
    RenderObjectIdRegistry() = default;

    RenderObjectId AllocateRenderObjectIdLocked();
    void BumpGenerationLocked();

    mutable std::mutex m_mutex = {};
    RenderObjectId m_nextRenderObjectId = 1u;
    Core::uint64 m_generation = 1u;
    std::unordered_map<Core::uint64, RenderObjectId>
        m_renderObjectIdByRuntimeObjectId = {};
    std::unordered_map<RenderObjectId, Core::uint64>
        m_runtimeObjectIdByRenderObjectId = {};
};

} // namespace Rendering
} // namespace XCEngine