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#include "qwaylanddataoffer_p.h"
#include "qwaylanddatadevicemanager_p.h"
#include "qwaylanddisplay_p.h"

#include <QtCore/private/qcore_unix_p.h>
#include <QtGui/private/qguiapplication_p.h>
#include <qpa/qplatformclipboard.h>

#include <QtCore/QDebug>

QT_BEGIN_NAMESPACE

namespace QtWaylandClient {

static QString utf8Text()
{
    return QStringLiteral("text/plain;charset=utf-8");
}

QWaylandDataOffer::QWaylandDataOffer(QWaylandDisplay *display, struct ::wl_data_offer *offer)
    : QtWayland::wl_data_offer(offer)
    , m_display(display)
    , m_mimeData(new QWaylandMimeData(this))
{
}

QWaylandDataOffer::~QWaylandDataOffer()
{
    destroy();
}


QString QWaylandDataOffer::firstFormat() const
{
    if (m_mimeData->formats().isEmpty())
        return QString();

    return m_mimeData->formats().first();
}

QMimeData *QWaylandDataOffer::mimeData()
{
    return m_mimeData.data();
}

void QWaylandDataOffer::startReceiving(const QString &mimeType, int fd)
{
    receive(mimeType, fd);
    wl_display_flush(m_display->wl_display());
}

void QWaylandDataOffer::data_offer_offer(const QString &mime_type)
{
    m_mimeData->appendFormat(mime_type);
}

QWaylandMimeData::QWaylandMimeData(QWaylandAbstractDataOffer *dataOffer)
    : m_dataOffer(dataOffer)
{
}

QWaylandMimeData::~QWaylandMimeData()
{
}

void QWaylandMimeData::appendFormat(const QString &mimeType)
{
    m_types << mimeType;
    m_data.remove(mimeType); // Clear previous contents
}

bool QWaylandMimeData::hasFormat_sys(const QString &mimeType) const
{
    if (m_types.contains(mimeType))
        return true;

    if (mimeType == QStringLiteral("text/plain") && m_types.contains(utf8Text()))
        return true;

    return false;
}

QStringList QWaylandMimeData::formats_sys() const
{
    return m_types;
}

QVariant QWaylandMimeData::retrieveData_sys(const QString &mimeType, QMetaType type) const
{
    Q_UNUSED(type);

    if (m_data.contains(mimeType))
        return m_data.value(mimeType);

    QString mime = mimeType;

    if (!m_types.contains(mimeType)) {
        if (mimeType == QStringLiteral("text/plain") && m_types.contains(utf8Text()))
            mime = utf8Text();
        else
            return QVariant();
    }

    int pipefd[2];
    if (qt_safe_pipe(pipefd) == -1) {
        qWarning("QWaylandMimeData: pipe2() failed");
        return QVariant();
    }

    m_dataOffer->startReceiving(mime, pipefd[1]);

    close(pipefd[1]);

    QByteArray content;
    if (readData(pipefd[0], content) != 0) {
        qWarning("QWaylandDataOffer: error reading data for mimeType %s", qPrintable(mimeType));
        content = QByteArray();
    }

    close(pipefd[0]);
    m_data.insert(mimeType, content);
    return content;
}

int QWaylandMimeData::readData(int fd, QByteArray &data) const
{
    fd_set readset;
    FD_ZERO(&readset);
    FD_SET(fd, &readset);
    struct timeval timeout;
    timeout.tv_sec = 1;
    timeout.tv_usec = 0;

    Q_FOREVER {
        int ready = select(FD_SETSIZE, &readset, nullptr, nullptr, &timeout);
        if (ready < 0) {
            qWarning() << "QWaylandDataOffer: select() failed";
            return -1;
        } else if (ready == 0) {
            qWarning("QWaylandDataOffer: timeout reading from pipe");
            return -1;
        } else {
            char buf[4096];
            int n = QT_READ(fd, buf, sizeof buf);

            if (n < 0) {
                qWarning("QWaylandDataOffer: read() failed");
                return -1;
            } else if (n == 0) {
                return 0;
            } else if (n > 0) {
                data.append(buf, n);
            }
        }
    }
}

}

QT_END_NAMESPACE
