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

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** this package.

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

#include "qnetworkreplyimpl_p.h"

#include "qnetworkaccessbackend_p.h"

#include "qnetworkcookie.h"

#include "qabstractnetworkcache.h"

#include "QtCore/qcoreapplication.h"

#include "QtCore/qdatetime.h"

#include "QtNetwork/qsslconfiguration.h"

#include "qnetworkaccesshttpbackend_p.h"

#include <QtCore/QCoreApplication>

QT_BEGIN_NAMESPACE

inline QNetworkReplyImplPrivate::QNetworkReplyImplPrivate()

    : backend(0), outgoingData(0), outgoingDataBuffer(0),

      copyDevice(0),

      cacheEnabled(false), cacheSaveDevice(0),

      notificationHandlingPaused(false),

      bytesDownloaded(0), lastBytesDownloaded(-1), bytesUploaded(-1),

      httpStatusCode(0),

      state(Idle)

{

}

void QNetworkReplyImplPrivate::_q_startOperation()

{

    // ensure this function is only being called once

    if (state == Working) {

        qDebug("QNetworkReplyImpl::_q_startOperation was called more than once");

        return;

    }

    state = Working;

    if (!backend) {

        error(QNetworkReplyImpl::ProtocolUnknownError,

              QCoreApplication::translate("QNetworkReply", "Protocol \"%1\" is unknown").arg(url.scheme())); // not really true!;

        finished();

        return;

    }

    backend->open();

    if (state != Finished) {

        if (operation == QNetworkAccessManager::GetOperation)

            pendingNotifications.append(NotifyDownstreamReadyWrite);

        handleNotifications();

    }

}

void QNetworkReplyImplPrivate::_q_copyReadyRead()

{

    Q_Q(QNetworkReplyImpl);

    if (state != Working)

        return;

    if (!copyDevice || !q->isOpen())

        return;

    forever {

        qint64 bytesToRead = nextDownstreamBlockSize();

        if (bytesToRead == 0)

            // we'll be called again, eventually

            break;

        bytesToRead = qBound<qint64>(1, bytesToRead, copyDevice->bytesAvailable());

        QByteArray byteData;

        byteData.resize(bytesToRead);

        qint64 bytesActuallyRead = copyDevice->read(byteData.data(), byteData.size());

        if (bytesActuallyRead == -1) {

            byteData.clear();

            backendNotify(NotifyCopyFinished);

            break;

        }

        byteData.resize(bytesActuallyRead);

        readBuffer.append(byteData);

        if (!copyDevice->isSequential() && copyDevice->atEnd()) {

            backendNotify(NotifyCopyFinished);

            bytesDownloaded += bytesActuallyRead;

            break;

        }

        bytesDownloaded += bytesActuallyRead;

    }

    if (bytesDownloaded == lastBytesDownloaded) {

        // we didn't read anything

        return;

    }

    lastBytesDownloaded = bytesDownloaded;

    QVariant totalSize = cookedHeaders.value(QNetworkRequest::ContentLengthHeader);

    pauseNotificationHandling();

    emit q->downloadProgress(bytesDownloaded,

                             totalSize.isNull() ? Q_INT64_C(-1) : totalSize.toLongLong());

    emit q->readyRead();

    resumeNotificationHandling();

}

void QNetworkReplyImplPrivate::_q_copyReadChannelFinished()

{

    _q_copyReadyRead();

}

void QNetworkReplyImplPrivate::_q_bufferOutgoingDataFinished()

{

    Q_Q(QNetworkReplyImpl);

    // make sure this is only called once, ever.

    //_q_bufferOutgoingData may call it or the readChannelFinished emission

    if (state != Buffering)

        return;

    // disconnect signals

    QObject::disconnect(outgoingData, SIGNAL(readyRead()), q, SLOT(_q_bufferOutgoingData()));

    QObject::disconnect(outgoingData, SIGNAL(readChannelFinished()), q, SLOT(_q_bufferOutgoingDataFinished()));

    // finally, start the request

    QMetaObject::invokeMethod(q, "_q_startOperation", Qt::QueuedConnection);

}

void QNetworkReplyImplPrivate::_q_bufferOutgoingData()

{

    Q_Q(QNetworkReplyImpl);

    if (!outgoingDataBuffer) {

        // first call, create our buffer

        outgoingDataBuffer = new QRingBuffer();

        QObject::connect(outgoingData, SIGNAL(readyRead()), q, SLOT(_q_bufferOutgoingData()));

        QObject::connect(outgoingData, SIGNAL(readChannelFinished()), q, SLOT(_q_bufferOutgoingDataFinished()));

    }

    qint64 bytesBuffered = 0;

    qint64 bytesToBuffer = 0;

    // read data into our buffer

    forever {

        bytesToBuffer = outgoingData->bytesAvailable();

        // unknown? just try 2 kB, this also ensures we always try to read the EOF

        if (bytesToBuffer <= 0)

            bytesToBuffer = 2*1024;

        char *dst = outgoingDataBuffer->reserve(bytesToBuffer);

        bytesBuffered = outgoingData->read(dst, bytesToBuffer);

        if (bytesBuffered == -1) {

            // EOF has been reached.

            outgoingDataBuffer->chop(bytesToBuffer);

            _q_bufferOutgoingDataFinished();

            break;

        } else if (bytesBuffered == 0) {

            // nothing read right now, just wait until we get called again

            outgoingDataBuffer->chop(bytesToBuffer);

            break;

        } else {

            // don't break, try to read() again

            outgoingDataBuffer->chop(bytesToBuffer - bytesBuffered);

        }

    }

}

void QNetworkReplyImplPrivate::setup(QNetworkAccessManager::Operation op, const QNetworkRequest &req,

                                     QIODevice *data)

{

    Q_Q(QNetworkReplyImpl);

    outgoingData = data;

    request = req;

    url = request.url();

    operation = op;

    if (outgoingData && backend) {

        // there is data to be uploaded, e.g. HTTP POST.

        if (!backend->needsResetableUploadData() || !outgoingData->isSequential()) {

            // backend does not need upload buffering or

            // fixed size non-sequential

            // just start the operation

            QMetaObject::invokeMethod(q, "_q_startOperation", Qt::QueuedConnection);

        } else {

            bool bufferingDisallowed =

                    req.attribute(QNetworkRequest::DoNotBufferUploadDataAttribute,

                                             false).toBool();

            if (bufferingDisallowed) {

                // if a valid content-length header for the request was supplied, we can disable buffering

                // if not, we will buffer anyway

                if (req.header(QNetworkRequest::ContentLengthHeader).isValid()) {

                    QMetaObject::invokeMethod(q, "_q_startOperation", Qt::QueuedConnection);

                } else {

                    state = Buffering;

                    QMetaObject::invokeMethod(q, "_q_bufferOutgoingData", Qt::QueuedConnection);

                }

            } else {

                // _q_startOperation will be called when the buffering has finished.

                state = Buffering;

                QMetaObject::invokeMethod(q, "_q_bufferOutgoingData", Qt::QueuedConnection);

            }

        }

    } else {

        // No outgoing data (e.g. HTTP GET request)

        // or no backend

        // if no backend, _q_startOperation will handle the error of this

        QMetaObject::invokeMethod(q, "_q_startOperation", Qt::QueuedConnection);

    }

    q->QIODevice::open(QIODevice::ReadOnly);

}

void QNetworkReplyImplPrivate::backendNotify(InternalNotifications notification)

{

    Q_Q(QNetworkReplyImpl);

    if (!pendingNotifications.contains(notification))

        pendingNotifications.enqueue(notification);

    if (pendingNotifications.size() == 1)

        QCoreApplication::postEvent(q, new QEvent(QEvent::NetworkReplyUpdated));

}

void QNetworkReplyImplPrivate::handleNotifications()

{

    if (notificationHandlingPaused)

        return;

    NotificationQueue current = pendingNotifications;

    pendingNotifications.clear();

    if (state != Working)

        return;

    while (!current.isEmpty()) {

        InternalNotifications notification = current.dequeue();

        switch (notification) {

        case NotifyDownstreamReadyWrite:

            if (copyDevice)

                _q_copyReadyRead();

            else

                backend->downstreamReadyWrite();

            break;

        case NotifyCloseDownstreamChannel:

            backend->closeDownstreamChannel();

            break;

        case NotifyCopyFinished: {

            QIODevice *dev = copyDevice;

            copyDevice = 0;

            backend->copyFinished(dev);

            break;

        }

        }

    }

}

// Do not handle the notifications while we are emitting downloadProgress

// or readyRead

void QNetworkReplyImplPrivate::pauseNotificationHandling()

{

    notificationHandlingPaused = true;

}

// Resume notification handling

void QNetworkReplyImplPrivate::resumeNotificationHandling()

{

    Q_Q(QNetworkReplyImpl);

    notificationHandlingPaused = false;

    if (pendingNotifications.size() >= 1)

        QCoreApplication::postEvent(q, new QEvent(QEvent::NetworkReplyUpdated));

}

QAbstractNetworkCache *QNetworkReplyImplPrivate::networkCache() const

{

    if (!backend)

        return 0;

    return backend->networkCache();

}

void QNetworkReplyImplPrivate::createCache()

{

    // check if we can save and if we're allowed to

    if (!networkCache()

        || !request.attribute(QNetworkRequest::CacheSaveControlAttribute, true).toBool()

        || request.attribute(QNetworkRequest::CacheLoadControlAttribute,

                             QNetworkRequest::PreferNetwork).toInt()

            == QNetworkRequest::AlwaysNetwork)

        return;

    cacheEnabled = true;

}

bool QNetworkReplyImplPrivate::isCachingEnabled() const

{

    return (cacheEnabled && networkCache() != 0);

}

void QNetworkReplyImplPrivate::setCachingEnabled(bool enable)

{

    if (!enable && !cacheEnabled)

        return;                 // nothing to do

    if (enable && cacheEnabled)

        return;                 // nothing to do either!

    if (enable) {

        if (bytesDownloaded) {

            // refuse to enable in this case

            qCritical("QNetworkReplyImpl: backend error: caching was enabled after some bytes had been written");

            return;

        }

        createCache();

    } else {

        // someone told us to turn on, then back off?

        // ok... but you should make up your mind

        qDebug("QNetworkReplyImpl: setCachingEnabled(true) called after setCachingEnabled(false) -- "

               "backend %s probably needs to be fixed",

               backend->metaObject()->className());

        networkCache()->remove(url);

        cacheSaveDevice = 0;

        cacheEnabled = false;

    }

}

void QNetworkReplyImplPrivate::completeCacheSave()

{

    if (cacheEnabled && errorCode != QNetworkReplyImpl::NoError) {

        networkCache()->remove(url);

    } else if (cacheEnabled && cacheSaveDevice) {

        networkCache()->insert(cacheSaveDevice);

    }

    cacheSaveDevice = 0;

    cacheEnabled = false;

}

void QNetworkReplyImplPrivate::emitUploadProgress(qint64 bytesSent, qint64 bytesTotal)

{

    Q_Q(QNetworkReplyImpl);

    bytesUploaded = bytesSent;

    pauseNotificationHandling();

    emit q->uploadProgress(bytesSent, bytesTotal);

    resumeNotificationHandling();

}

qint64 QNetworkReplyImplPrivate::nextDownstreamBlockSize() const

{

    enum { DesiredBufferSize = 32 * 1024 };

    if (readBufferMaxSize == 0)

        return DesiredBufferSize;

    return qMax<qint64>(0, readBufferMaxSize - readBuffer.byteAmount());

}

// we received downstream data and send this to the cache

// and to our readBuffer (which in turn gets read by the user of QNetworkReply)

void QNetworkReplyImplPrivate::appendDownstreamData(QByteDataBuffer &data)

{

    Q_Q(QNetworkReplyImpl);

    if (!q->isOpen())

        return;

    if (cacheEnabled && !cacheSaveDevice) {

        // save the meta data

        QNetworkCacheMetaData metaData;

        metaData.setUrl(url);

        metaData = backend->fetchCacheMetaData(metaData);

        // save the redirect request also in the cache

        QVariant redirectionTarget = q->attribute(QNetworkRequest::RedirectionTargetAttribute);

        if (redirectionTarget.isValid()) {

            QNetworkCacheMetaData::AttributesMap attributes = metaData.attributes();

            attributes.insert(QNetworkRequest::RedirectionTargetAttribute, redirectionTarget);

            metaData.setAttributes(attributes);

        }

        cacheSaveDevice = networkCache()->prepare(metaData);

        if (!cacheSaveDevice || (cacheSaveDevice && !cacheSaveDevice->isOpen())) {

            if (cacheSaveDevice && !cacheSaveDevice->isOpen())

                qCritical("QNetworkReplyImpl: network cache returned a device that is not open -- "

                      "class %s probably needs to be fixed",

                      networkCache()->metaObject()->className());

            networkCache()->remove(url);

            cacheSaveDevice = 0;

            cacheEnabled = false;

        }

    }

    qint64 bytesWritten = 0;

    for (int i = 0; i < data.bufferCount(); i++) {

        QByteArray item = data[i];

        if (cacheSaveDevice)

            cacheSaveDevice->write(item.constData(), item.size());

        readBuffer.append(item);

        bytesWritten += item.size();

    }

    data.clear();

    bytesDownloaded += bytesWritten;

    lastBytesDownloaded = bytesDownloaded;

    QPointer<QNetworkReplyImpl> qq = q;

    QVariant totalSize = cookedHeaders.value(QNetworkRequest::ContentLengthHeader);

    pauseNotificationHandling();

    emit q->downloadProgress(bytesDownloaded,

                             totalSize.isNull() ? Q_INT64_C(-1) : totalSize.toLongLong());

    // important: At the point of this readyRead(), the data parameter list must be empty,

    // else implicit sharing will trigger memcpy when the user is reading data!

    emit q->readyRead();

    // hopefully we haven't been deleted here

    if (!qq.isNull()) {

        resumeNotificationHandling();

        // do we still have room in the buffer?

        if (nextDownstreamBlockSize() > 0)

            backendNotify(QNetworkReplyImplPrivate::NotifyDownstreamReadyWrite);

    }

}

// this is used when it was fetched from the cache, right?

void QNetworkReplyImplPrivate::appendDownstreamData(QIODevice *data)

{

    Q_Q(QNetworkReplyImpl);

    if (!q->isOpen())

        return;

    // read until EOF from data

    if (copyDevice) {

        qCritical("QNetworkReplyImpl: copy from QIODevice already in progress -- "

                  "backend probly needs to be fixed");

        return;

    }

    copyDevice = data;

    q->connect(copyDevice, SIGNAL(readyRead()), SLOT(_q_copyReadyRead()));

    q->connect(copyDevice, SIGNAL(readChannelFinished()), SLOT(_q_copyReadChannelFinished()));

    // start the copy:

    _q_copyReadyRead();

}

void QNetworkReplyImplPrivate::finished()

{

    Q_Q(QNetworkReplyImpl);

    if (state == Finished || state == Aborted)

        return;

    state = Finished;

    pendingNotifications.clear();

    pauseNotificationHandling();

    QVariant totalSize = cookedHeaders.value(QNetworkRequest::ContentLengthHeader);

    if (totalSize.isNull() || totalSize == -1) {

        emit q->downloadProgress(bytesDownloaded, bytesDownloaded);

    }

    if (bytesUploaded == -1 && (outgoingData || outgoingDataBuffer))

        emit q->uploadProgress(0, 0);

    resumeNotificationHandling();

    completeCacheSave();

    // note: might not be a good idea, since users could decide to delete us

    // which would delete the backend too...

    // maybe we should protect the backend

    pauseNotificationHandling();

    emit q->readChannelFinished();

    emit q->finished();

    resumeNotificationHandling();

}

void QNetworkReplyImplPrivate::error(QNetworkReplyImpl::NetworkError code, const QString &errorMessage)

{

    Q_Q(QNetworkReplyImpl);

    errorCode = code;

    q->setErrorString(errorMessage);

    // note: might not be a good idea, since users could decide to delete us

    // which would delete the backend too...

    // maybe we should protect the backend