abstract_state.h

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#ifndef HEDGEHOG_ABSTRACT_STATE_H
#define HEDGEHOG_ABSTRACT_STATE_H

#include <memory>
#include <queue>
#include <shared_mutex>

#include "../../behavior/execute.h"
#include "../../tools/traits.h"

namespace hh {

template<class StateOutput, class ...StateInputs>
class AbstractState : public behavior::Execute<StateInputs> ... {
  static_assert(traits::isUnique<StateInputs...>, "A Task can't accept multiple inputs with the same type.");
  static_assert(sizeof... (StateInputs) >= 1, "A state need to have one output type and at least one output type.");
 private:
  mutable std::unique_ptr<std::shared_mutex> stateMutex_ = nullptr; 
  std::unique_ptr<std::queue<std::shared_ptr<StateOutput>>> readyList_ = nullptr; 

 public:
  AbstractState() {
    stateMutex_ = std::make_unique<std::shared_mutex>();
    readyList_ = std::make_unique<std::queue<std::shared_ptr<StateOutput>>>();
  }

  virtual ~AbstractState() = default;

  std::unique_ptr<std::queue<std::shared_ptr<StateOutput>>> const &readyList() const { return readyList_; }

  void push(std::shared_ptr<StateOutput> const &elem) { readyList_->push(elem); }

  std::shared_ptr<StateOutput> frontAndPop() {
    std::shared_ptr<StateOutput> elem = readyList_->front();
    readyList_->pop();
    return elem;
  }

  void lock() { stateMutex_->lock(); }

  void unlock() { stateMutex_->unlock(); }
};

}
#endif //HEDGEHOG_ABSTRACT_STATE_H