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#ifndef QNETWORKACCESSBACKEND_P_H

#define QNETWORKACCESSBACKEND_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 "qnetworkreplyimpl_p.h"

#include "QtCore/qobject.h"

QT_BEGIN_NAMESPACE

class QAuthenticator;

class QNetworkProxy;

class QNetworkProxyQuery;

class QNetworkRequest;

class QUrl;

class QUrlInfo;

class QSslConfiguration;

class QNetworkAccessManagerPrivate;

class QNetworkReplyImplPrivate;

class QAbstractNetworkCache;

class QNetworkCacheMetaData;

class QNetworkAccessBackendUploadIODevice;

class QNonContiguousByteDevice;

// Should support direct file upload from disk or download to disk.

//

// - The HTTP handler will use two QIODevices for communication (pull mechanism)

// - KIO uses a pull mechanism too (data/dataReq signals)

class QNetworkAccessBackend : public QObject

{

    Q_OBJECT

public:

    QNetworkAccessBackend();

    virtual ~QNetworkAccessBackend();

    // To avoid mistaking with QIODevice names, the functions here

    // have different names. The Connection has two streams:

    //

    // - Upstream:

    //   The upstream uses a QNonContiguousByteDevice provided

    //   by the backend. This device emits the usual readyRead()

    //   signal when the backend has data available for the connection

    //   to write. The different backends can listen on this signal

    //   and then pull upload data from the QNonContiguousByteDevice and

    //   deal with it.

    //

    //

    // - Downstream:

    //   Downstream is the data that is being read from this

    //   connection and is given to the user. Downstream operates in a

    //   semi-"push" mechanism: the Connection object pushes the data

    //   it gets from the network, but it should avoid writing too

    //   much if the data isn't being used fast enough. The value

    //   returned by suggestedDownstreamBlockSize() can be used to

    //   determine how much should be written at a time. The

    //   downstreamBytesConsumed() function will be called when the

    //   downstream buffer is consumed by the user -- the Connection

    //   may choose to re-fill it with more data it has ready or get

    //   more data from the network (for instance, by reading from its

    //   socket).

    virtual void open() = 0;

    virtual void closeDownstreamChannel() = 0;

    virtual bool waitForDownstreamReadyRead(int msecs) = 0;

    // slot-like:

    virtual void downstreamReadyWrite();

    virtual void setDownstreamLimited(bool b);

    virtual void copyFinished(QIODevice *);

    virtual void ignoreSslErrors();

    virtual void ignoreSslErrors(const QList<QSslError> &errors);

    virtual void fetchSslConfiguration(QSslConfiguration &configuration) const;

    virtual void setSslConfiguration(const QSslConfiguration &configuration);

    virtual QNetworkCacheMetaData fetchCacheMetaData(const QNetworkCacheMetaData &metaData) const;

    // information about the request

    QNetworkAccessManager::Operation operation() const;

    QNetworkRequest request() const;

#ifndef QT_NO_NETWORKPROXY

    QList<QNetworkProxy> proxyList() const;

#endif

    QAbstractNetworkCache *networkCache() const;

    void setCachingEnabled(bool enable);

    bool isCachingEnabled() const;

    // information about the reply

    QUrl url() const;

    void setUrl(const QUrl &url);

    // "cooked" headers

    QVariant header(QNetworkRequest::KnownHeaders header) const;

    void setHeader(QNetworkRequest::KnownHeaders header, const QVariant &value);

    // raw headers:

    bool hasRawHeader(const QByteArray &headerName) const;

    QList<QByteArray> rawHeaderList() const;

    QByteArray rawHeader(const QByteArray &headerName) const;

    void setRawHeader(const QByteArray &headerName, const QByteArray &value);

    // attributes:

    QVariant attribute(QNetworkRequest::Attribute code) const;

    void setAttribute(QNetworkRequest::Attribute code, const QVariant &value);

    // return true if the QNonContiguousByteDevice of the upload

    // data needs to support reset(). Currently needed for HTTP.

    // This will possibly enable buffering of the upload data.

    virtual bool needsResetableUploadData() { return false; }

protected:

    // Create the device used for reading the upload data

    QNonContiguousByteDevice* createUploadByteDevice();

    // these functions control the downstream mechanism

    // that is, data that has come via the connection and is going out the backend

    qint64 nextDownstreamBlockSize() const;

    void writeDownstreamData(QByteDataBuffer &list);

public slots:

    // for task 251801, needs to be a slot to be called asynchronously

    void writeDownstreamData(QIODevice *data);

protected slots:

    void finished();

    void error(QNetworkReply::NetworkError code, const QString &errorString);

#ifndef QT_NO_NETWORKPROXY

    void proxyAuthenticationRequired(const QNetworkProxy &proxy, QAuthenticator *auth);

#endif

    void authenticationRequired(QAuthenticator *auth);

    void metaDataChanged();

    void redirectionRequested(const QUrl &destination);

    void sslErrors(const QList<QSslError> &errors);

    void emitReplyUploadProgress(qint64 bytesSent, qint64 bytesTotal);

private:

    friend class QNetworkAccessManager;

    friend class QNetworkAccessManagerPrivate;

    friend class QNetworkAccessBackendUploadIODevice;

    QNetworkAccessManagerPrivate *manager;

    QNetworkReplyImplPrivate *reply;

};

class QNetworkAccessBackendFactory

{

public:

    QNetworkAccessBackendFactory();

    virtual ~QNetworkAccessBackendFactory();

    virtual QNetworkAccessBackend *create(QNetworkAccessManager::Operation op,

                                          const QNetworkRequest &request) const = 0;

};

QT_END_NAMESPACE

#endif