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

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** this package.

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

#ifndef QNETWORKACCESSCACHE_P_H

#define QNETWORKACCESSCACHE_P_H

//

//  W A R N I N G

//  -------------

//

// This file is not part of the Qt API.  It exists for the convenience

// of the Network Access API.  This header file may change from

// version to version without notice, or even be removed.

//

// We mean it.

//

#include "QtCore/qobject.h"

#include "QtCore/qbasictimer.h"

#include "QtCore/qbytearray.h"

#include "QtCore/qhash.h"

#include "QtCore/qmetatype.h"

QT_BEGIN_NAMESPACE

class QNetworkRequest;

class QUrl;

// this class is not about caching files but about

// caching objects used by QNetworkAccessManager, e.g. existing TCP connections

// or credentials.

class QNetworkAccessCache: public QObject

{

    Q_OBJECT

public:

    struct Node;

    typedef QHash<QByteArray, Node> NodeHash;

    class CacheableObject

    {

        friend class QNetworkAccessCache;

        QByteArray key;

        bool expires;

        bool shareable;

    public:

        CacheableObject();

        virtual ~CacheableObject();

        virtual void dispose() = 0;

        inline QByteArray cacheKey() const { return key; }

    protected:

        void setExpires(bool enable);

        void setShareable(bool enable);

    };

    QNetworkAccessCache();

    ~QNetworkAccessCache();

    void clear();

    void addEntry(const QByteArray &key, CacheableObject *entry);

    bool hasEntry(const QByteArray &key) const;

    bool requestEntry(const QByteArray &key, QObject *target, const char *member);

    CacheableObject *requestEntryNow(const QByteArray &key);

    void releaseEntry(const QByteArray &key);

    void removeEntry(const QByteArray &key);

signals:

    void entryReady(QNetworkAccessCache::CacheableObject *);

protected:

    void timerEvent(QTimerEvent *);

private:

    // idea copied from qcache.h

    NodeHash hash;

    Node *oldest;

    Node *newest;

    QBasicTimer timer;

    void linkEntry(const QByteArray &key);

    bool unlinkEntry(const QByteArray &key);

    void updateTimer();

    bool emitEntryReady(Node *node, QObject *target, const char *member);

};

QT_END_NAMESPACE

Q_DECLARE_METATYPE(QNetworkAccessCache::CacheableObject*)

#endif