state_manager.h

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#ifndef HEDGEHOG_STATE_MANAGER_H_
#define HEDGEHOG_STATE_MANAGER_H_
 
#include <utility>
 
#include "abstract_state.h"
#include "../../behavior/copyable.h"
#include "../../behavior/task_node.h"
 
namespace hh {
 
template<size_t Separator, class ...AllTypes>
class StateManager
    : public behavior::TaskNode,
      public behavior::CanTerminate,
      public behavior::Cleanable,
      public behavior::Copyable<StateManager<Separator, AllTypes...>>,
      public tool::BehaviorMultiReceiversTypeDeducer_t<tool::Inputs<Separator, AllTypes...>>,
      public tool::BehaviorMultiSendersTypeDeducer_t<tool::Outputs<Separator, AllTypes...>> {
 private:
  std::shared_ptr<AbstractState<Separator, AllTypes...>> state_ = nullptr; 
  std::shared_ptr<core::CoreStateManager<Separator, AllTypes...>> coreStateManager_ = nullptr; 
 
 public:
  explicit StateManager(
      std::shared_ptr<AbstractState<Separator, AllTypes...>> state,
      std::string const &name = "State manager",
      bool const automaticStart = false)
      : behavior::TaskNode(std::make_shared<core::CoreStateManager<Separator, AllTypes...>>(this,
                                                                                            state,
                                                                                            name,
                                                                                            automaticStart)),
        behavior::Copyable<StateManager<Separator, AllTypes...>>(1),
        tool::BehaviorMultiSendersTypeDeducer_t<tool::Outputs<Separator, AllTypes...>>(),
        state_(state) {
    if (state == nullptr) {
      throw std::runtime_error("The state given to the state manager should be valid (!= nullptr).");
    }
 
    if (auto
        coreStateManager = std::dynamic_pointer_cast<core::CoreStateManager<Separator, AllTypes...>>(this->core())) {
      coreStateManager_ = coreStateManager;
    } else {
      throw std::runtime_error("The core used by the state manager should be a CoreStateManager.");
    }
  }
 
  explicit StateManager(
      std::shared_ptr<core::CoreStateManager<Separator, AllTypes...>> core,
      std::shared_ptr<AbstractState<Separator, AllTypes...>> state)
      : behavior::TaskNode(std::move(core)),
        behavior::Copyable<StateManager<Separator, AllTypes...>>(1),
        tool::BehaviorMultiSendersTypeDeducer_t<tool::Outputs<Separator, AllTypes...>>() {
    if (state == nullptr) {
      throw std::runtime_error("The state given to the state manager should be valid (!= nullptr).");
    }
    if (this->core() == nullptr) {
      throw std::runtime_error("The core given to the state manager should be valid (!= nullptr).");
    }
    if (auto
        coreStateManager = std::dynamic_pointer_cast<core::CoreStateManager<Separator, AllTypes...>>(this->core())) {
      coreStateManager_ = coreStateManager;
    } else {
      throw std::runtime_error("The core used by the state manager should be a CoreStateManager.");
    }
  }
 
  ~StateManager() override = default;
 
  std::shared_ptr<AbstractState<Separator, AllTypes...>> const &state() const { return state_; }
 
  [[nodiscard]] bool automaticStart() const { return this->coreStateManager()->automaticStart(); }
 
  std::shared_ptr<core::CoreStateManager<Separator, AllTypes...>> const &coreStateManager() const {
    return coreStateManager_;
  }
 
  [[nodiscard]] bool canTerminate() const override {
    return !coreStateManager_->hasNotifierConnected() && coreStateManager_->receiversEmpty();
  }
 
  std::shared_ptr<StateManager<Separator, AllTypes...>> copy() final {
    auto copy = copyStateManager(this->state_);
    if (copy == nullptr) {
      std::ostringstream oss;
      oss
          << "A copy of the state manager " << this->name() << " has been invoked but return nullptr. "
          << "Please implement the copyStateManager method to create a copy of the current state manager with the same state.";
      throw std::runtime_error(oss.str());
    }
    if (copy->state_ != this->state_) {
      std::ostringstream oss;
      oss << "A copy and the state manager \"" << this->name() << "\" do not share the same state.\n";
      throw std::runtime_error(oss.str());
    }
    return copy;
  }
 
  virtual std::shared_ptr<StateManager<Separator, AllTypes...>>
  copyStateManager(std::shared_ptr<AbstractState<Separator, AllTypes...>> state) {
    return std::make_shared<StateManager<Separator, AllTypes...>>(state, this->name(), this->automaticStart());
  }
 
};
}
 
#endif //HEDGEHOG_STATE_MANAGER_H_