AnswerQueue.h

#pragma once

#include <list>

#include <Poco/Event.h>
#include <Poco/Timespan.h>

#include "core/Answer.h"
#include "util/Loggable.h"

namespace BeeeOn {

/*
 * The responses are added to the queue during the Answer creation. After
 * the status is changed in the Result, the Answer is set to dirty and the
 * Answer notifies the queue about this change.
 *
 * It is possible to wait for Answer from queue for a given time using
 * wait(Timespan, dirtyList). After a given time Answers with the set dirty
 * (the status Response was set to the Answers) are stored to the dirtyList.
 */
class AnswerQueue : public Loggable {
        friend Answer;
public:
        AnswerQueue();

        /*
         * Blocking waiting for the list of the Answers in which
         * change Results were.  Returns true if the event became
         * signalled within the specified time interval, false otherwise.
         */
        bool wait(const Poco::Timespan &timeout,
                std::list<Answer::Ptr> &dirtyList);

        Answer::Ptr newAnswer();

        void remove(const Answer::Ptr answer);

        std::list<Answer::Ptr> finishedAnswers();

        Poco::Event &event();

        unsigned long size() const;

        void dispose();

        void notifyUpdated();

protected:
        void add(Answer *answer);

        bool isDisposed() const;

        bool block(const Poco::Timespan &timeout);

        /*
         * List of Answer, which were set as dirty.
         */
        void listDirty(std::list<Answer::Ptr> &dirtyList) const;

protected:
        std::list<Answer::Ptr> m_answerList;
        Poco::Event m_event;
        mutable Poco::FastMutex m_mutex;
        Poco::AtomicCounter m_disposed;
};

}