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#include "qdirectpainter_qws.h"

#include "qscreen_qws.h"

#include "private/qobject_p.h"

#include "private/qapplication_p.h"

#include "qwsdisplay_qws.h"

#include "qwidget.h"

#include "qimage.h"

#include <qwsevent_qws.h>

#include <private/qwindowsurface_qws_p.h>

#include <private/qwsdisplay_qws_p.h>

QT_BEGIN_NAMESPACE

#ifdef Q_WS_QWS

#ifndef QT_NO_DIRECTPAINTER

/*!

    \class QDirectPainter

    \ingroup painting

    \ingroup qws

    \brief The QDirectPainter class provides direct access to the

    underlying hardware in Qt for Embedded Linux.

    Note that this class is only available in \l{Qt for Embedded Linux}.

    QDirectPainter allows a client application to reserve a region of

    the framebuffer and render directly onto the screen. There are two

    ways of using the QDirectPainter class: You can either reserve a

    region using the provided static functions, or you can instantiate

    an object and make use of its more dynamic API.

    \tableofcontents

    \section1 Dynamic Allocation

    By instantiating a QDirectPainter object using the default

    QDirectPainter::NonReserved surface flag, the client application

    only gets some control over the reserved region, i.e., it can

    still render directly onto the screen but the allocated region may

    change (for example, if a window with a higher focus requests

    parts of the same region). The currently allocated region can be

    retrieved using the allocatedRegion() function, while the

    requestedRegion() function returns the originally reserved

    region.

    \section1 Static Allocation

    Using the static approach, the client application gets complete

    control over the reserved region, i.e., the affected region will

    never be modified by the screen driver.

    To create a static region, pass the QDirectPainter::Reserved

    surface flag to the constructor. After the reserved region is

    reported through regionChanged(), the allocated region will not

    change, unless setRegion() is called.

    If QDirectPainter::ReservedSynchronous is passed to the

    constructor, calls to setRegion() will block until the region is

    reserved, meaning that allocatedRegion() will be available immediately.

    Note that in the current version setRegion() will cause the application

    event loop to be entered, potentially causing reentrancy issues.

    \section1 Rendering

    To draw on a given region, the application must first get hold of

    a pointer to the framebuffer. In most cases, this pointer can be

    retrieved using the QDirectPainter::frameBuffer() function. But

    note that if the current screen has subscreens, you must query the

    screen driver instead to identify the correct subscreen. A pointer

    to the current screen driver can always be retrieved using the

    static QScreen::instance() function. Then use QScreen's \l

    {QScreen::}{subScreenIndexAt()} and \l {QScreen::}{subScreens()}

    functions to access the correct subscreen, and the subscreen's \l

    {QScreen::}{base()} function to retrieve a pointer to the

    framebuffer.

    Depending on the hardware, it might be necessary to lock the

    framebuffer for exclusive use while writing to it. This is

    possible using the lock() and unlock() functions. Note that

    calling lock() will prevent all other applications from working

    until unlock() is called.

    In addition, QDirectPainter provides several functions returning

    information about the framebuffer: the linestep() function returns

    the length (in bytes) of each scanline of the framebuffer while

    the screenDepth(), screenWidth() and screenHeight() function

    return the screen metrics.

    \sa QScreen, QWSEmbedWidget, {Qt for Embedded Linux Architecture}

*/

/*!

    \enum QDirectPainter::SurfaceFlag

    This enum describes the behavior of the region reserved by this

    QDirectPainter object.

    \value NonReserved The allocated region may change, e.g., if a

    window with a higher focus requests parts of the same region. See

    also \l {Dynamic Allocation}.

    \value Reserved The allocated region will never change. See also

    \l {Static Allocation}.

    \value ReservedSynchronous The allocated region will never change and

    each function that changes the allocated region will be blocking.

    \sa allocatedRegion()

*/

/*!

    \fn QRegion QDirectPainter::region()

    \obsolete

    Use QDirectPainter::allocatedRegion() instead.

*/

static inline QScreen *getPrimaryScreen()

{

    QScreen *screen = QScreen::instance();

    if (!screen->base()) {

        QList<QScreen*> subScreens = screen->subScreens();

        if (subScreens.size() < 1)

            return 0;

        screen = subScreens.at(0);

    }

    return screen;

}

static inline QSize screenS()

{

    QScreen *screen = getPrimaryScreen();

    if (!screen)

        return QSize();

    return QSize(screen->width(), screen->height());

}

static inline QSize devS()

{

    QScreen *screen = getPrimaryScreen();

    if (!screen)

        return QSize();

    return QSize(screen->deviceWidth(), screen->deviceHeight());

}

class QDirectPainterPrivate : public QObjectPrivate

{

    Q_DECLARE_PUBLIC(QDirectPainter);

public:

    QDirectPainterPrivate() : surface(0), seenRegion(false) {}

    ~QDirectPainterPrivate() {

        if (QPaintDevice::qwsDisplay()) { // make sure not in QApplication destructor

            qApp->d_func()->directPainters->remove(surface->windowId());

            surface->setGeometry(QRect());

        }

        delete surface;

    }

    QWSDirectPainterSurface *surface;

    QRegion requested_region;

    static QDirectPainter *staticPainter;

    bool seenRegion;

};

QDirectPainter *QDirectPainterPrivate::staticPainter = 0;

void qt_directpainter_region(QDirectPainter *dp, const QRegion &alloc, int type)

{

    QDirectPainterPrivate *d = dp->d_func();

    QRegion r = alloc;

    QScreen *screen = d->surface->screen();

    if (screen->isTransformed()) {

        const QSize screenSize(screen->width(), screen->height());

        r = screen->mapToDevice(r, screenSize);

    }

    if (type == QWSRegionEvent::Allocation) {

        d->surface->setClipRegion(alloc);

        d->seenRegion = true;

        if (dp != QDirectPainterPrivate::staticPainter) {

            if (!d->surface->flushingRegionEvents) // recursion guard

                dp->regionChanged(r);

        }

    }

}

#ifndef QT_NO_QWSEMBEDWIDGET

void qt_directpainter_embedevent(QDirectPainter *dp, const QWSEmbedEvent *event)

{

    if (event->type | QWSEmbedEvent::Region) {

        QScreen *screen = dp->d_func()->surface->screen();

        QRegion r = event->region;

        if (screen->isTransformed()) {

            const QSize screenSize(screen->width(), screen->height());

            r = screen->mapToDevice(r, screenSize);

        }

        dp->setRegion(r);

    }

}

#endif

/*!

    Constructs a QDirectPainter object with the given \a parent and

    surface \a flag.

*/

QDirectPainter::QDirectPainter(QObject *parent, SurfaceFlag flag)

    :QObject(*new QDirectPainterPrivate, parent)

{

    Q_D(QDirectPainter);

    d->surface = new QWSDirectPainterSurface(true, flag);

    if (flag != NonReserved)

        d->surface->setReserved();

    QApplicationPrivate *ad = qApp->d_func();

    if (!ad->directPainters)

        ad->directPainters = new QMap<WId, QDirectPainter*>;

    ad->directPainters->insert(d->surface->windowId(), this);

}

/*!

    Destroys this QDirectPainter object, releasing the reserved region.

    \sa allocatedRegion()

*/

QDirectPainter::~QDirectPainter()

{

    /* should not be necessary

    if (this == QDirectPainterPrivate::staticPainter)

        QDirectPainterPrivate::staticPainter = 0;

    */

}

/*!

    \fn void QDirectPainter::setGeometry(const QRect &rectangle)

    \since 4.2

    Request to reserve the given \a rectangle of the framebuffer.

    Note that the actually allocated region might differ from the

    requested one, e.g., if the given region overlaps with the

    region of another QDirectPainter object.

    \sa geometry(), allocatedRegion(), setRegion()

*/

void QDirectPainter::setGeometry(const QRect &rect)

{

    setRegion(rect);

}

/*!

    \since 4.2

    Returns the bounding rectangle of the requested region.

    \sa setGeometry(), requestedRegion()

*/

QRect QDirectPainter::geometry() const

{

    Q_D(const QDirectPainter);

    return d->requested_region.boundingRect();

}

/*!

    \since 4.2

    Requests to reserve the given \a region of the framebuffer.

    Note that the actually allocated region might differ from the

    requested one, e.g., if the given region overlaps with the region

    of another QDirectPainter object.

    \sa requestedRegion(), allocatedRegion(), {Dynamic Allocation}

*/

void QDirectPainter::setRegion(const QRegion &region)

{

    Q_D(QDirectPainter);

    d->requested_region = region;

    const QScreen *screen = d->surface->screen();

    if (screen->isTransformed()) {

        const QSize devSize(screen->deviceWidth(), screen->deviceHeight());

        const QRegion r = screen->mapFromDevice(region, devSize);

        d->surface->setRegion(r);

    } else {

        d->surface->setRegion(region);

    }

}

/*!

    \since 4.2

    Returns the region requested by this QDirectPainter.

    Note that if the QDirectPainter::Reserved flag is set, the region

    returned by this function will always be equivalent to the region

    returned by the allocatedRegion() function. Otherwise they might

    differ (see \l {Dynamic Allocation} for details).

    \sa geometry(), setRegion(), allocatedRegion()

*/

QRegion QDirectPainter::requestedRegion() const

{

    Q_D(const QDirectPainter);

    return d->requested_region;

}

/*!

    \since 4.2

    Returns the currently reserved region.

    Note that if the QDirectPainter::Reserved flag is set, the region

    returned by this function will always be equivalent to the region

    returned by the requestedRegion() function. Otherwise they might

    differ (see \l {Dynamic Allocation} for details).

    \sa requestedRegion(), geometry()

*/

QRegion QDirectPainter::allocatedRegion() const

{

    Q_D(const QDirectPainter);

    const QScreen *screen = d->surface->screen();

    if (screen->isTransformed()) {

        const QSize screenSize(screen->width(), screen->height());

        return screen->mapToDevice(d->surface->region(), screenSize);

    } else {

        return d->surface->region();

    }

}

/*!

    \since 4.2

    Returns the window system identifier of the widget.

*/

WId QDirectPainter::winId() const

{

    Q_D(const QDirectPainter);

    return d->surface->windowId();

}

/*!

    \fn void QDirectPainter::regionChanged(const QRegion &newRegion)

    \since 4.2

    This function is called when the allocated region changes.

    This function is not called for region changes that happen while the

    startPainting() function is executing.

    Note that the given region, \a newRegion, is not guaranteed to be correct at the

    time you access the display. To prevent reentrancy problems you should

    always call startPainting() before updating the display and then use

    allocatedRegion() to retrieve the correct region.

    \sa allocatedRegion(), startPainting(), {Dynamic Allocation}

*/

void QDirectPainter::regionChanged(const QRegion &region)

{

    Q_UNUSED(region);

}

/*!

    \since 4.2

    Call this function before you start updating the pixels in the

    allocated region. The hardware will be notified, if necessary,

    that you are about to start painting operations.

    Set \a lockDisplay if you want startPainting() and endPainting()

    to lock() and unlock() the display automatically.

    Note that for a NonReserved direct painter, you must call

    allocatedRegion() after calling this function, since the allocated

    region is only guaranteed to be correct after this function has

    returned.

    The regionChanged() function will not be called between startPainting()

    and endPainting().

    \sa endPainting(), flush()

*/

void QDirectPainter::startPainting(bool lockDisplay)

{

    Q_D(QDirectPainter);

    d->surface->setLocking(lockDisplay);

    const QScreen *screen = d->surface->screen();

    if (screen->isTransformed()) {

        const QSize devSize(screen->deviceWidth(), screen->deviceHeight());

        const QRegion r = screen->mapFromDevice(d->surface->region(), devSize);

        d->surface->beginPaint(r);

    } else {

        d->surface->beginPaint(d->surface->region());

    }

}

/*!

    \since 4.2

    Call this function when you are done updating the screen. It will

    notify the hardware, if necessary, that your painting operations

    have ended.

*/

void QDirectPainter::endPainting()

{

    Q_D(QDirectPainter);

    const QScreen *screen = d->surface->screen();

    if (screen->isTransformed()) {

        const QSize devSize(screen->deviceWidth(), screen->deviceHeight());

        const QRegion r = screen->mapFromDevice(d->surface->region(), devSize);

        d->surface->endPaint(r);

    } else {

        d->surface->endPaint(d->surface->region());

    }

}

/*!

    \since 4.3

    \overload

    This function will automatically call flush() to flush the

    \a region to the display before notifying the hardware, if

    necessary, that painting operations have ended.

*/

void QDirectPainter::endPainting(const QRegion &region)

{

    endPainting();

    flush(region);

}

/*!

    \since 4.3

    Flushes the \a region onto the screen.

*/

void QDirectPainter::flush(const QRegion &region)

{

    Q_D(QDirectPainter);

    const QScreen *screen = d->surface->screen();

    if (screen->isTransformed()) {

        const QSize devSize(screen->deviceWidth(), screen->deviceHeight());

        const QRegion r = screen->mapFromDevice(region, devSize);

        d->surface->flush(0, r, QPoint());

    } else {

        d->surface->flush(0, region, QPoint());

    }

}

/*!

    \since 4.2

    Raises the reserved region to the top of the widget stack.

    After this call the reserved region will be visually in front of

    any overlapping widgets.

    \sa lower(), requestedRegion()

*/

void QDirectPainter::raise()

{

    QWidget::qwsDisplay()->setAltitude(winId(),QWSChangeAltitudeCommand::Raise);

}

/*!

    \since 4.2

    Lowers the reserved region to the bottom of the widget stack.

    After this call the reserved region will be visually behind (and

    therefore obscured by) any overlapping widgets.

    \sa raise(), requestedRegion()

*/

void QDirectPainter::lower()

{