问用图数据结构实现状态模式

EN

class ExecutionParameters;
class IState;
using SPState = std::shared_ptr<IState>;
using SPStates = std::list<SPState>;
class _declspec(novtable) IState
{
public:
    virtual void Execute(Context& context, const ExecutionParameters& params) = 0;
    virtual SPStates GetAdjacentStates() const noexcept = 0;
};

class _declspec(novtable) ITransitionCriteria
{
public:
    virtual SPState ComputeNextState() const = 0;
};

class CostBasedTransition : public ITransitionCriteria
{
public:
    SPState ComputeNextState() const override
    {
         // Find min transition cost adjacent node
    }
};
using SPTransitionCriteria = std::shared_ptr<ITransitionCriteria>;

class StateNode : public IState
{
public:
    StateNode(int id, SPTransitionCriteria spTransitionCriteria) :m_id(id), m_spTransitionCriteria(spTransitionCriteria)
    {}
    StateNode(int id) :StateNode(id, nullptr)//Choose default transition criteria//)
    {}

    void Execute(Context& context, const ExecutionParameters& params) override
    {
        // Perform action

        // Update context state
        context.SetState(m_spTransitionCriteria->GetNextState());
    }

    SPStates GetAdjacentStates() const noexcept
    {
        return m_spAdjacentStates;
    }

    void AddAjacentState(SPState spState)
    {
    }

    void RemoveAjacentState(int stateId)
    {
    }
private:
    int m_id;
    SPStates m_spAdjacentStates;
    SPTransitionCriteria m_spTransitionCriteria;
};

class Context
{
public:
    void Execute(const ExecutionParameters& params)
    {
        m_spState->Execute(*this, params);
    }

    void SetState(SPState& spState)
    {
        m_spState = spState;
    }
private:
    SPState m_spState;
};