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****************************************************************************/

#ifndef QFUTUREINTERFACE_H

#define QFUTUREINTERFACE_H

#include <QtCore/qglobal.h>

#include <QtCore/qrunnable.h>

#ifndef QT_NO_QFUTURE

#include <QtCore/qmutex.h>

#include <QtCore/qtconcurrentexception.h>

#include <QtCore/qtconcurrentresultstore.h>

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE

QT_MODULE(Core)

template <typename T> class QFuture;

class QFutureInterfaceBasePrivate;

class QFutureWatcherBase;

class QFutureWatcherBasePrivate;

class Q_CORE_EXPORT QFutureInterfaceBase

{

public:

    enum State {

        NoState   = 0x00,

        Running   = 0x01,

        Started   = 0x02,

        Finished  = 0x04,

        Canceled  = 0x08,

        Paused    = 0x10,

        Throttled = 0x20

    };

    QFutureInterfaceBase(State initialState = NoState);

    QFutureInterfaceBase(const QFutureInterfaceBase &other);

    virtual ~QFutureInterfaceBase();

    // reporting functions available to the engine author:

    void reportStarted();

    void reportFinished();

    void reportCanceled();

#ifndef QT_NO_EXCEPTIONS

    void reportException(const QtConcurrent::Exception &e);

#endif

    void reportResultsReady(int beginIndex, int endIndex);

    void setRunnable(QRunnable *runnable);

    void setFilterMode(bool enable);

    void setProgressRange(int minimum, int maximum);

    int progressMinimum() const;

    int progressMaximum() const;

    bool isProgressUpdateNeeded() const;

    void setProgressValue(int progressValue);

    int progressValue() const;

    void setProgressValueAndText(int progressValue, const QString &progressText);

    QString progressText() const;

    void setExpectedResultCount(int resultCount);

    int expectedResultCount();

    int resultCount() const;

    bool queryState(State state) const;

    bool isRunning() const;

    bool isStarted() const;

    bool isCanceled() const;

    bool isFinished() const;

    bool isPaused() const;

    bool isThrottled() const;

    bool isResultReadyAt(int index) const;

    void cancel();

    void setPaused(bool paused);

    void togglePaused();

    void setThrottled(bool enable);

    void waitForFinished();

    bool waitForNextResult();

    void waitForResult(int resultIndex);

    void waitForResume();

    QMutex *mutex() const;

    QtConcurrent::internal::ExceptionStore &exceptionStore();

    QtConcurrent::ResultStoreBase &resultStoreBase();

    const QtConcurrent::ResultStoreBase &resultStoreBase() const;

    inline bool operator==(const QFutureInterfaceBase &other) const { return d == other.d; }

    inline bool operator!=(const QFutureInterfaceBase &other) const { return d != other.d; }

    QFutureInterfaceBase &operator=(const QFutureInterfaceBase &other);

protected:

    bool referenceCountIsOne() const;

public:

#ifndef QFUTURE_TEST

private:

#endif

    QFutureInterfaceBasePrivate *d;

private:

    friend class QFutureWatcherBase;

    friend class QFutureWatcherBasePrivate;

};

template <typename T>

class QFutureInterface : public QFutureInterfaceBase

{

public:

    QFutureInterface(State initialState = NoState)

        : QFutureInterfaceBase(initialState)

    { }

    QFutureInterface(const QFutureInterface &other)

        : QFutureInterfaceBase(other)

    { }

    ~QFutureInterface()

    {

        if (referenceCountIsOne())

            resultStore().clear();

    }

    static QFutureInterface canceledResult()

    { return QFutureInterface(State(Started | Finished | Canceled)); }

    QFutureInterface &operator=(const QFutureInterface &other)

    {

        if (referenceCountIsOne())

            resultStore().clear();

        QFutureInterfaceBase::operator=(other);

        return *this;

    }

    inline QFuture<T> future(); // implemented in qfuture.h

    inline void reportResult(const T *result, int index = -1);

    inline void reportResult(const T &result, int index = -1);

    inline void reportResults(const QVector<T> &results, int beginIndex = -1, int count = -1);

    inline void reportFinished(const T *result = 0);

    inline const T &resultReference(int index) const;

    inline const T *resultPointer(int index) const;

    inline QList<T> results();

private:

    QtConcurrent::ResultStore<T> &resultStore()

    { return static_cast<QtConcurrent::ResultStore<T> &>(resultStoreBase()); }

    const QtConcurrent::ResultStore<T> &resultStore() const

    { return static_cast<const QtConcurrent::ResultStore<T> &>(resultStoreBase()); }

};

template <typename T>

inline void QFutureInterface<T>::reportResult(const T *result, int index)

{

    QMutexLocker locker(mutex());

    if (this->queryState(Canceled) || this->queryState(Finished)) {

        return;

    }

    QtConcurrent::ResultStore<T> &store = resultStore();

    if (store.filterMode()) {

        const int resultCountBefore = store.count();

        store.addResult(index, result);

        this->reportResultsReady(resultCountBefore, resultCountBefore + store.count());

    } else {

        const int insertIndex = store.addResult(index, result);

        this->reportResultsReady(insertIndex, insertIndex + 1);

    }

}

template <typename T>

inline void QFutureInterface<T>::reportResult(const T &result, int index)

{

    reportResult(&result, index);

}

template <typename T>

inline void QFutureInterface<T>::reportResults(const QVector<T> &_results, int beginIndex, int count)

{

    QMutexLocker locker(mutex());

    if (this->queryState(Canceled) || this->queryState(Finished)) {

        return;

    }

    QtConcurrent::ResultStore<T> &store = resultStore();

    if (store.filterMode()) {

        const int resultCountBefore = store.count();

        store.addResults(beginIndex, &_results, count);

        this->reportResultsReady(resultCountBefore, store.count());

    } else {

        const int insertIndex = store.addResults(beginIndex, &_results, count);

        this->reportResultsReady(insertIndex, insertIndex + _results.count());    

    }

}

template <typename T>

inline void QFutureInterface<T>::reportFinished(const T *result)

{

    if (result)

        reportResult(result);

    QFutureInterfaceBase::reportFinished();

}

template <typename T>

inline const T &QFutureInterface<T>::resultReference(int index) const

{

    QMutexLocker lock(mutex());

    return resultStore().resultAt(index).value();

}

template <typename T>

inline const T *QFutureInterface<T>::resultPointer(int index) const

{

    QMutexLocker lock(mutex());

    return resultStore().resultAt(index).pointer();

}

template <typename T>

inline QList<T> QFutureInterface<T>::results()

{

    if (this->isCanceled()) {

        exceptionStore().throwPossibleException();

        return QList<T>();

    }

    QFutureInterfaceBase::waitForResult(-1);

    QList<T> res;

    QMutexLocker lock(mutex());

    QtConcurrent::ResultIterator<T> it = resultStore().begin();

    while (it != resultStore().end()) {

        res.append(it.value());

        ++it;

    }

    return res;

}

template <>

class QFutureInterface<void> : public QFutureInterfaceBase

{

public:

    QFutureInterface<void>(State initialState = NoState)

        : QFutureInterfaceBase(initialState)

    { }

    QFutureInterface<void>(const QFutureInterface<void> &other)

        : QFutureInterfaceBase(other)

    { }

    static QFutureInterface<void> canceledResult()

    { return QFutureInterface(State(Started | Finished | Canceled)); }

    QFutureInterface<void> &operator=(const QFutureInterface<void> &other)

    {

        QFutureInterfaceBase::operator=(other);

        return *this;

    }

    inline QFuture<void> future(); // implemented in qfuture.h

    void reportResult(const void *, int) { }

    void reportResults(const QVector<void> &, int) { }

    void reportFinished(void * = 0) { QFutureInterfaceBase::reportFinished(); }

};

QT_END_NAMESPACE

QT_END_HEADER

#endif // QT_NO_CONCURRENT

#endif // QFUTUREINTERFACE_H