ProxyAspect.hpp

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#ifndef DART_COMMON_DETAIL_PROXYASPECT_HPP_
#define DART_COMMON_DETAIL_PROXYASPECT_HPP_

#include "dart/common/Aspect.hpp"

namespace dart {
namespace common {
namespace detail {

//==============================================================================
template <class BaseT, class CompositeT, typename StateT>
class ProxyStateAspect : public BaseT
{
public:
  using Base = BaseT;
  using CompositeType = CompositeT;
  using State = StateT;

  virtual ~ProxyStateAspect() = default;

  template <typename... Args>
  ProxyStateAspect(Args&&... args)
    : Base(std::forward<Args>(args)...), mProxyState()
  {
    // Do nothing
  }

  // Documentation inherited
  void setAspectState(const Aspect::State& state) override final
  {
    mProxyState.set(static_cast<const State&>(state));
  }

  // Documentation inherited
  const Aspect::State* getAspectState() const override final
  {
    return &mProxyState;
  }

  // Documentation inherited
  std::unique_ptr<Aspect> cloneAspect() const override
  {
    return std::make_unique<ProxyStateAspect>();
  }

protected:
  void setComposite(Composite* newComposite) override
  {
    Base::setComposite(newComposite);

    // Check if the Composite is the correct Owner type
    typename State::Owner* owner
        = dynamic_cast<typename State::Owner*>(newComposite);

    if (owner && mProxyState.getOwner() != owner)
    {
      // Link the ProxyState to its new owner
      mProxyState = State(owner, mProxyState.get());
    }
  }

  void loseComposite(Composite* oldComposite) override
  {
    mProxyState = State(mProxyState.get());
    Base::loseComposite(oldComposite);
  }

  State mProxyState;
};

//==============================================================================
template <class BaseT, class CompositeT, typename PropertiesT>
class ProxyPropertiesAspect : public BaseT
{
public:
  using Base = BaseT;
  using CompositeType = CompositeT;
  using Properties = PropertiesT;

  virtual ~ProxyPropertiesAspect() = default;

  template <typename... Args>
  ProxyPropertiesAspect(Args&&... args)
    : Base(std::forward<Args>(args)...), mProxyProperties()
  {
    // Do nothing
  }

  // Documentation inherited
  void setAspectProperties(const Aspect::Properties& properties) override final
  {
    mProxyProperties.set(static_cast<const Properties&>(properties));
  }

  // Documentation inherited
  const Aspect::Properties* getAspectProperties() const override final
  {
    return &mProxyProperties;
  }

  // Documentation inherited
  std::unique_ptr<Aspect> cloneAspect() const override
  {
    return std::make_unique<ProxyPropertiesAspect>();
  }

protected:
  void setComposite(Composite* newComposite) override
  {
    Base::setComposite(newComposite);
    typename Properties::Owner* owner
        = dynamic_cast<typename Properties::Owner*>(newComposite);

    if (owner && mProxyProperties.getOwner() != owner)
    {
      // Link the ProxyProperties to its new owner
      mProxyProperties = Properties(owner, mProxyProperties.get());
    }
  }

  void loseComposite(Composite* oldComposite) override
  {
    mProxyProperties = Properties(mProxyProperties.get());
    Base::loseComposite(oldComposite);
  }

  Properties mProxyProperties;
};

} // namespace detail
} // namespace common
} // namespace dart

#endif // DART_COMMON_DETAIL_PROXYASPECT_HPP_