#ifndef ADVSAHREDMEMORYMANAGER_H
#define ADVSAHREDMEMORYMANAGER_H

#include "advabstractmemorymanager.h"
#include "advmemorymanager_global.h"
#include <QSharedMemory>
#include <QDebug>
#ifdef Q_OS_LINUX
#include <fcntl.h>
#include <sys/shm.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <unistd.h>
#endif

template <class T>
class ADVSahredMemoryManager : public ADVAbstractMemoryManager<T>
{
public:
    explicit ADVSahredMemoryManager(const QString &key) : ADVAbstractMemoryManager<T>(), m_key(key), shm(new QSharedMemory) { instantiateMemory(); }
    virtual ~ADVSahredMemoryManager() { freeMemory(); }

    bool isValid() {return m_valid;}

protected:
    void instantiateMemory()
    {
        dataPtr = nullptr;
        shm->setNativeKey(m_key);
        if (attach()) {
            qWarning()<<QObject::tr("Shm exists, attached")<<m_key<<"!";
            m_valid = true;
        } else {
            if (create())
            {
#ifndef Q_OS_LINUX
                dataPtr = shm->data();
#endif
                memset(dataPtr, 0, sizeof(T));

                qWarning()<<QObject::tr("Shm created")<<m_key;
                m_valid = true;
            } else {
                qWarning()<<QObject::tr("Cannot create shm")<<m_key<<"!!!";
                m_valid = false;
                return;
            }
        }
        ADVAbstractMemoryManager<T>::setDataPointer(reinterpret_cast<T *>(dataPtr));
    }

    void freeMemory()
    {
        if (isAttached()) {
            qDebug()<<"Detach"<<m_key;
            detach();
        }
        delete shm;
    }

private:
    QString m_key;
    QSharedMemory *shm;
    void *dataPtr;

    bool m_valid;

    bool attach() {
#ifndef Q_OS_LINUX
        if (shm->attach()) {
            dataPtr = shm->data();
            return true;
        }
        return false;
#endif
#ifdef Q_OS_LINUX
        int shm_fd = shm_open(shm->nativeKey().toUtf8().toStdString().c_str(), O_RDWR, 0666);
        if (shm_fd >= 0) {
            dataPtr = mmap(nullptr, sizeof(T), PROT_READ | PROT_WRITE, MAP_SHARED, shm_fd, 0);
            if (dataPtr)
                return true;
        }
        return false;
#endif
    }
    void detach() {
#ifndef Q_OS_LINUX
        shm->detach();
#endif
#ifdef Q_OS_LINUX
        shm_unlink(shm->nativeKey().toUtf8().toStdString().c_str());
#endif
    }
    bool create() {
#ifndef Q_OS_LINUX
        return shm->create(sizeof(T));
#endif
#ifdef Q_OS_LINUX
        int shm_fd = shm_open(shm->nativeKey().toUtf8().toStdString().c_str(), O_RDWR | O_CREAT | O_EXCL, 0666);
        if (shm_fd >= 0) {
            int ret = ftruncate(shm_fd, sizeof(T));
            if (ret == 0)
                dataPtr = mmap(nullptr, sizeof(T), PROT_READ | PROT_WRITE, MAP_SHARED, shm_fd, 0);
            else {
                qDebug()<<"Error code ftruncate : "<<errno;
                detach();
            }
            if (dataPtr)
                return true;
            else
                detach();
        }
        return false;
#endif
    }
    bool isAttached() {
#ifndef Q_OS_LINUX
        return shm->isAttached();
#endif
#ifdef Q_OS_LINUX
        return dataPtr != nullptr;
#endif
    }
};

#endif // ADVSAHREDMEMORYMANAGER_H

IF NOT shmOpened THEN
    IF shmHandler <> 0 THEN
        SysSharedMemoryClose(shmHandler);
    END_IF
    shmSize := SIZEOF(SharedArea);
    shmHandler := SysSharedMemoryOpen2(shmKey, 0, ADR(shmSize), ADR(shmOpenResult));
    IF shmOpenResult = 0 AND shmHandler > 0 THEN
        areaExchange := SysSharedMemoryGetPointer(shmHandler, ADR(shmPointerResult));
        ShmGlv.fieldArea REF= areaExchange^;
        IF shmPointerResult = 0 THEN
            shmOpened := TRUE;
        END_IF
    END_IF
ELSE
    IF areaExchange^.watchDogPC = areaExchange^.watchDogPLC THEN
        areaExchange^.watchDogPLC := areaExchange^.watchDogPLC + 1;
        shmCounterWatchdog := 0;
        IF areaExchange^.watchDogPC > 0 THEN
            IF NOT shmConnected THEN
                shmConnected := TRUE;
            END_IF;
        END_IF
    ELSE
        shmCounterWatchdog := shmCounterWatchdog + 1;
        IF shmCounterWatchdog >= MAX_WATCHDOG_COUNTER THEN
            IF shmConnected THEN
                shmConnected := FALSE;
            END_IF
        END_IF
    END_IF;
END_IF