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// #define QBBWINDOW_DEBUG

#include "qbbwindow.h"
#include "qbbglcontext.h"
#include "qbbscreen.h"

#include <QtGui/QWidget>
#include <QDebug>
#include <QtGui/QPlatformWindowFormat>
#include <QtGui/QWindowSystemInterface>

#include <errno.h>

QT_BEGIN_NAMESPACE

QBBWindow::QBBWindow(QWidget *window, screen_context_t context, QBBScreen *screen)
    : QPlatformWindow(window),
      mContext(context),
      mCurrentBufferIndex(-1),
      mPreviousBufferIndex(-1),
      mPlatformGlContext(NULL),
      mScreen(NULL),
      mParent(NULL),
      mVisible(true)
{
#if defined(QBBWINDOW_DEBUG)
    qDebug() << "QBBWindow::QBBWindow - w=" << window << ", s=" << window->size();
#endif
    int result;

    // create child QNX window
    errno = 0;
    result = screen_create_window_type(&mWindow, mContext, SCREEN_CHILD_WINDOW);
    if (result != 0) {
        qFatal("QBBWindow: failed to create window, errno=%d", errno);
    }

    // set window buffer usage based on rendering API
    int val;
    QPlatformWindowFormat format = widget()->platformWindowFormat();
    switch (format.windowApi()) {
    case QPlatformWindowFormat::Raster:
        val = SCREEN_USAGE_NATIVE | SCREEN_USAGE_READ | SCREEN_USAGE_WRITE;
        break;
    case QPlatformWindowFormat::OpenGL:
        val = SCREEN_USAGE_OPENGL_ES2;
        break;
    default:
        qFatal("QBBWindow: unsupported window API");
        break;
    }

    errno = 0;
    result = screen_set_window_property_iv(mWindow, SCREEN_PROPERTY_USAGE, &val);
    if (result != 0) {
        qFatal("QBBWindow: failed to set window buffer usage, errno=%d", errno);
    }

    // alpha channel is always pre-multiplied if present
    errno = 0;
    val = SCREEN_PRE_MULTIPLIED_ALPHA;
    result = screen_set_window_property_iv(mWindow, SCREEN_PROPERTY_ALPHA_MODE, &val);
    if (result != 0) {
        qFatal("QBBWindow: failed to set window alpha mode, errno=%d", errno);
    }

    // make the window opaque
    errno = 0;
    val = SCREEN_TRANSPARENCY_NONE;
    result = screen_set_window_property_iv(mWindow, SCREEN_PROPERTY_TRANSPARENCY, &val);
    if (result != 0) {
        qFatal("QBBWindow: failed to set window transparency, errno=%d", errno);
    }

    // set the window swap interval
    errno = 0;
    val = 1;
    result = screen_set_window_property_iv(mWindow, SCREEN_PROPERTY_SWAP_INTERVAL, &val);
    if (result != 0) {
        qFatal("QBBWindow: failed to set window swap interval, errno=%d", errno);
    }

    // Set the screen to the primary display (this is the default specified by screen).
    setScreen(screen);

    // Qt somtimes doesn't call these setters after creating the window, so we need to do that
    // ourselves here
    if (window->parentWidget() && window->parentWidget()->platformWindow())
        setParent(window->parentWidget()->platformWindow());
    setGeometry(window->geometry());
    setVisible(window->isVisible());
}

QBBWindow::~QBBWindow()
{
#if defined(QBBWINDOW_DEBUG)
    qDebug() << "QBBWindow::~QBBWindow - w=" << widget();
#endif

    // Qt should have already deleted the children before deleting the parent.
    Q_ASSERT(mChildren.size() == 0);

    // Remove from parent's Hierarchy.
    removeFromParent();
    mScreen->updateHierarchy();

    // cleanup OpenGL/OpenVG context if it exists
    if (mPlatformGlContext != NULL) {
        delete mPlatformGlContext;
    }

    // cleanup QNX window and its buffers
    screen_destroy_window(mWindow);
}

void QBBWindow::setGeometry(const QRect &rect)
{
    int val[2];

#if defined(QBBWINDOW_DEBUG)
    qDebug() << "QBBWindow::setGeometry - w=" << widget() << ", (" << rect.x() << "," << rect.y() << "," << rect.width() << "," << rect.height() << ")";
#endif

    QRect oldGeometry = geometry();

    // call parent method
    QPlatformWindow::setGeometry(rect);

    // set window geometry equal to widget geometry
    errno = 0;
    val[0] = rect.x();
    val[1] = rect.y();
    int result = screen_set_window_property_iv(mWindow, SCREEN_PROPERTY_POSITION, val);
    if (result != 0) {
        qFatal("QBBWindow: failed to set window position, errno=%d", errno);
    }

    errno = 0;
    val[0] = rect.width();
    val[1] = rect.height();
    result = screen_set_window_property_iv(mWindow, SCREEN_PROPERTY_SIZE, val);
    if (result != 0) {
        qFatal("QBBWindow: failed to set window size, errno=%d", errno);
    }

    // set viewport size equal to window size
    errno = 0;
    result = screen_set_window_property_iv(mWindow, SCREEN_PROPERTY_SOURCE_SIZE, val);
    if (result != 0) {
        qFatal("QBBWindow: failed to set window source size, errno=%d", errno);
    }

    // Now move all children.
    QPoint offset;
    if (!oldGeometry.isEmpty()) {
        offset = rect.topLeft();
        offset -= oldGeometry.topLeft();

        QList<QBBWindow*>::iterator it;
        for (it = mChildren.begin(); it != mChildren.end(); it++) {
            (*it)->offset(offset);
        }
    }
}

void QBBWindow::offset(const QPoint &offset)
{
    // Move self and then children.
    QRect newGeometry = geometry();
    newGeometry.translate(offset);

    // call the base class
    QPlatformWindow::setGeometry(newGeometry);

    int val[2];

    errno = 0;
    val[0] = newGeometry.x();
    val[1] = newGeometry.y();
    int result = screen_set_window_property_iv(mWindow, SCREEN_PROPERTY_POSITION, val);
    if (result != 0) {
        qFatal("QBBWindow: failed to set window position, errno=%d", errno);
    }

    QList<QBBWindow*>::iterator it;
    for (it = mChildren.begin(); it != mChildren.end(); it++) {
        (*it)->offset(offset);
    }
}

void QBBWindow::setVisible(bool visible)
{
#if defined(QBBWINDOW_DEBUG)
    qDebug() << "QBBWindow::setVisible - w=" << widget() << ", v=" << visible;
#endif

    mVisible = visible;

    QBBWindow* root = this;
    while (root->mParent)
        root = root->mParent;

    root->updateVisibility(root->mVisible);

    widget()->activateWindow();

    // Flush the context when invisible, otherwise it won't disappear immediately,
    // but still allow navigator to capture screenshot (thumbnail) when minimized
    if (!visible && !(widget()->windowState() & Qt::WindowMinimized))
        screen_flush_context(mContext, 0);
}

void QBBWindow::updateVisibility(bool parentVisible)
{
    // set window visibility
    errno = 0;
    int val = (mVisible && parentVisible) ? 1 : 0;
    int result = screen_set_window_property_iv(mWindow, SCREEN_PROPERTY_VISIBLE, &val);
    if (result != 0) {
        qFatal("QBBWindow: failed to set window visibility, errno=%d", errno);
    }

    QList<QBBWindow*>::iterator it;
    for (it = mChildren.begin(); it != mChildren.end(); it++) {
        (*it)->updateVisibility(mVisible && parentVisible);
    }
}

void QBBWindow::setOpacity(qreal level)
{
#if defined(QBBWINDOW_DEBUG)
    qDebug() << "QBBWindow::setOpacity - w=" << widget() << ", o=" << level;
#endif

    // set window global alpha
    errno = 0;
    int val = (int)(level * 255);
    int result = screen_set_window_property_iv(mWindow, SCREEN_PROPERTY_GLOBAL_ALPHA, &val);
    if (result != 0) {
        qFatal("QBBWindow: failed to set window global alpha, errno=%d", errno);
    }

    // TODO: How to handle children of this window? If we change all the visibilities, then
    //       the transparency will look wrong...
}

void QBBWindow::setBufferSize(const QSize &size)
{
#if defined(QBBWINDOW_DEBUG)
    qDebug() << "QBBWindow::setBufferSize - w=" << widget() << ", s=" << size;
#endif

    // set window buffer size
    errno = 0;
    int val[2] = { size.width(), size.height() };
    int result = screen_set_window_property_iv(mWindow, SCREEN_PROPERTY_BUFFER_SIZE, val);
    if (result != 0) {
        qFatal("QBBWindow: failed to set window buffer size, errno=%d", errno);
    }

    // create window buffers if they do not exist
    if (!hasBuffers()) {
#if defined(QBBWINDOW_DEBUG)
        qDebug() << "QBBWindow::setBufferSize - create buffers";
#endif

        // get pixel format from EGL config if using OpenGL;
        // otherwise inherit pixel format of window's screen
        if (mPlatformGlContext != NULL) {
            val[0] = platformWindowFormatToNativeFormat(mPlatformGlContext->platformWindowFormat());
        } else {
            val[0] = mScreen->nativeFormat();
        }

        errno = 0;
        result = screen_set_window_property_iv(mWindow, SCREEN_PROPERTY_FORMAT, val);
        if (result != 0) {
            qFatal("QBBWindow: failed to set window pixel format, errno=%d", errno);
        }

        errno = 0;
        result = screen_create_window_buffers(mWindow, MAX_BUFFER_COUNT);
        if (result != 0) {
            qFatal("QBBWindow: failed to create window buffers, errno=%d", errno);
        }

        // check if there are any buffers available
        int bufferCount = 0;
        result = screen_get_window_property_iv(mWindow, SCREEN_PROPERTY_RENDER_BUFFER_COUNT, &bufferCount);

        if (result != 0) {
            qFatal("QBBWindow: failed to query window buffer count, errno=%d", errno);
        }

        if (bufferCount != MAX_BUFFER_COUNT) {
            qFatal("QBBWindow: invalid buffer count. Expected = %d, got = %d", MAX_BUFFER_COUNT, bufferCount);
        }
    }

    // cache new buffer size
    mBufferSize = size;

    // buffers were destroyed; reacquire them
    mCurrentBufferIndex = -1;
    mPreviousDirty = QRegion();
    mScrolled = QRegion();
}

QBBBuffer &QBBWindow::renderBuffer()
{
#if defined(QBBWINDOW_DEBUG)
    qDebug() << "QBBWindow::renderBuffer - w=" << widget();
#endif

    return buffer(BACK_BUFFER);
}

QBBBuffer &QBBWindow::frontBuffer()
{
#if defined(QBBWINDOW_DEBUG)
    qDebug() << "QBBWindow::frontBuffer - w=" << widget();
#endif

    return buffer(FRONT_BUFFER);
}

QBBBuffer &QBBWindow::buffer(QBBWindow::Buffer bufferIndex)
{
#if defined(QBBWINDOW_DEBUG)
    qDebug() << "QBBWindow::buffer - w=" << widget();
#endif

    // check if render buffer is invalid
    if (mCurrentBufferIndex == -1) {
        // get all buffers available for rendering
        errno = 0;
        screen_buffer_t buffers[MAX_BUFFER_COUNT];
        const int result = screen_get_window_property_pv(mWindow, SCREEN_PROPERTY_RENDER_BUFFERS, (void **)buffers);
        if (result != 0) {
            qFatal("QBBWindow: failed to query window buffers, errno=%d", errno);
        }

        // wrap each buffer
        for (int i = 0; i < MAX_BUFFER_COUNT; i++) {
            mBuffers[i] = QBBBuffer(buffers[i]);
        }

        // use the first available render buffer
        mCurrentBufferIndex = 0;
        mPreviousBufferIndex = -1;
    }

    if (bufferIndex == BACK_BUFFER) {
        return mBuffers[mCurrentBufferIndex];
    } else if (bufferIndex == FRONT_BUFFER) {
        int buf = mCurrentBufferIndex - 1;

        if (buf < 0)
            buf = MAX_BUFFER_COUNT - 1;

        return mBuffers[buf];
    }

    qFatal("QBBWindow::buffer() - invalid buffer index. Aborting");

    // never happens
    return mBuffers[mCurrentBufferIndex];
}

void QBBWindow::scroll(const QRegion &region, int dx, int dy, bool flush)
{
    copyBack(region, dx, dy, flush);
    mScrolled += region;
}

void QBBWindow::post(const QRegion &dirty)
{
    // check if render buffer exists and something was rendered
    if (mCurrentBufferIndex != -1 && !dirty.isEmpty()) {

#if defined(QBBWINDOW_DEBUG)
        qDebug() << "QBBWindow::post - w=" << widget();
#endif
        QBBBuffer &currentBuffer = mBuffers[mCurrentBufferIndex];

        // copy unmodified region from old render buffer to new render buffer;
        // required to allow partial updates
        QRegion preserve = mPreviousDirty - dirty - mScrolled;
        copyBack(preserve, 0, 0);

        // calculate region that changed
        QRegion modified = preserve + dirty + mScrolled;
        QRect rect = modified.boundingRect();
        int dirtyRect[4] = { rect.x(), rect.y(), rect.x() + rect.width(), rect.y() + rect.height() };

        // update the display with contents of render buffer
        errno = 0;
        int result = screen_post_window(mWindow, currentBuffer.nativeBuffer(), 1, dirtyRect, 0);
        if (result != 0) {
            qFatal("QBBWindow: failed to post window buffer, errno=%d", errno);
        }

        // advance to next nender buffer
        mPreviousBufferIndex = mCurrentBufferIndex++;
        if (mCurrentBufferIndex >= MAX_BUFFER_COUNT) {
            mCurrentBufferIndex = 0;
        }

        // save modified region and clear scrolled region
        mPreviousDirty = dirty;
        mScrolled = QRegion();

        // notify screen that window posted
        if (mScreen != NULL) {
            mScreen->onWindowPost(this);
        }
    }
}

QPlatformGLContext *QBBWindow::glContext() const
{
#if defined(QBBWINDOW_DEBUG)
    qDebug() << "QBBWindow::glContext - w=" << widget();
#endif
    // create opengl context on first access if rendering API is correct
    QPlatformWindowFormat format = widget()->platformWindowFormat();
    if (mPlatformGlContext == NULL && format.windowApi() == QPlatformWindowFormat::OpenGL) {
        mPlatformGlContext = new QBBGLContext( const_cast<QBBWindow*>(this) );
    }
    return mPlatformGlContext;
}

void QBBWindow::setScreen(QBBScreen *platformScreen)
{
#if defined(QBBWINDOW_DEBUG)
    qDebug() << "QBBWindow::setScreen - w=" << widget();
#endif

    if (mScreen == platformScreen)
        return;

    if (mScreen)
        mScreen->removeWindow(this);
    platformScreen->addWindow(this);
    mScreen = platformScreen;

    // The display may not have a root (desktop) window yet so we must ensure that one has been
    // created before we can join its group or get its native display property.
    mScreen->ensureDisplayCreated();

    // move window to proper display
    errno = 0;
    screen_display_t display = platformScreen->nativeDisplay();
    int result = screen_set_window_property_pv(mWindow, SCREEN_PROPERTY_DISPLAY, (void **)&display);
    if (result != 0) {
        qFatal("QBBWindow: failed to set window display, errno=%d", errno);
    }

    // add window to display's window group
    errno = 0;
    result = screen_join_window_group(mWindow, platformScreen->windowGroupName());
    if (result != 0) {
        qFatal("QBBWindow: failed to join window group, errno=%d", errno);
    }

    QList<QBBWindow*>::iterator it;
    for (it = mChildren.begin(); it != mChildren.end(); it++) {
        // Only subwindows and tooltips need necessarily be moved to another display with
        // the window.
        if ((widget()->windowType() & Qt::WindowType_Mask) == Qt::SubWindow ||
            (widget()->windowType() & Qt::WindowType_Mask) == Qt::ToolTip)
            (*it)->setScreen(platformScreen);
    }

    mScreen->updateHierarchy();
}

void QBBWindow::removeFromParent()
{
    // Remove from old Hierarchy position
    if (mParent) {
        if (mParent->mChildren.removeAll(this))
            mParent = 0;
        else
            qFatal("QBBWindow: Window Hierarchy broken; window has parent, but parent hasn't got child.");
    } else {
        mScreen->removeWindow(this);
    }
}

void QBBWindow::setParent(const QPlatformWindow *window)
{
#if defined(QBBWINDOW_DEBUG)
    qDebug() << "QBBWindow::setParent - w=" << widget() << " p=" << window;
#endif

    // Cast away the const, we need to modify the Hierarchy.
    QBBWindow* newParent = 0;

    if (window)
        newParent = static_cast<QBBWindow*>((QPlatformWindow *)window);

    if (newParent == mParent)
        return;

    removeFromParent();
    mParent = newParent;

    // Add to new Hierarchy position.
    if (mParent) {
        if (mParent->mScreen != mScreen)
            setScreen(mParent->mScreen);

        mParent->mChildren.push_back(this);
    } else {
        mScreen->addWindow(this);
    }

    mScreen->updateHierarchy();
}

void QBBWindow::raise()
{
#if defined(QBBWINDOW_DEBUG)
    qDebug() << "QBBWindow::raise - w=" << widget();
#endif

    if (mParent) {
        mParent->mChildren.removeAll(this);
        mParent->mChildren.push_back(this);
    } else {
        mScreen->raiseWindow(this);
    }

    mScreen->updateHierarchy();
}

void QBBWindow::lower()
{
#if defined(QBBWINDOW_DEBUG)
    qDebug() << "QBBWindow::lower - w=" << widget();
#endif

    if (mParent) {
        mParent->mChildren.removeAll(this);
        mParent->mChildren.push_front(this);
    } else {
        mScreen->lowerWindow(this);
    }

    mScreen->updateHierarchy();
}

void QBBWindow::requestActivateWindow()
{
#if defined(QBBWINDOW_DEBUG)
    qDebug() << "QBBWindow::requestActivateWindow - w=" << widget();
#endif

    // TODO: Tell screen to set keyboard focus to this window.

    // Notify that we gained focus.
    gainedFocus();
}

void QBBWindow::gainedFocus()
{
#if defined(QBBWINDOW_DEBUG)
    qDebug() << "QBBWindow::gainedFocus - w=" << widget();
#endif

    // Got focus
    QWindowSystemInterface::handleWindowActivated(widget());
}

QBBWindow *QBBWindow::findWindow(screen_window_t windowHandle)
{
    if (mWindow == windowHandle)
        return this;

    Q_FOREACH (QBBWindow *window, mChildren) {
        QBBWindow * const result = window->findWindow(windowHandle);
        if (result)
            return result;
    }

    return 0;
}

void QBBWindow::updateZorder(int &topZorder)
{
    errno = 0;
    int result = screen_set_window_property_iv(mWindow, SCREEN_PROPERTY_ZORDER, &topZorder);
    topZorder++;

    if (result != 0)
        qFatal("QBBWindow: failed to set window z-order=%d, errno=%d, mWindow=0x%08x", topZorder, errno, mWindow);

    QList<QBBWindow*>::const_iterator it;

    for (it = mChildren.begin(); it != mChildren.end(); it++)
        (*it)->updateZorder(topZorder);
}

void QBBWindow::copyBack(const QRegion &region, int dx, int dy, bool flush)
{
    int result;

    // abort if previous buffer is invalid
    if (mPreviousBufferIndex == -1) {
        return;
    }

    // abort if nothing to copy
    if (region.isEmpty()) {
        return;
    }

    QBBBuffer &currentBuffer = mBuffers[mCurrentBufferIndex];
    QBBBuffer &previousBuffer = mBuffers[mPreviousBufferIndex];

    // break down region into non-overlapping rectangles
    QVector<QRect> rects = region.rects();
    for (int i = rects.size() - 1; i >= 0; i--) {

        // clip rectangle to bounds of target
        QRect rect = rects[i].intersected( currentBuffer.rect() );

        if (rect.isEmpty())
            continue;

        // setup blit operation
        int attribs[] = { SCREEN_BLIT_SOURCE_X, rect.x(),
                          SCREEN_BLIT_SOURCE_Y, rect.y(),
                          SCREEN_BLIT_SOURCE_WIDTH, rect.width(),
                          SCREEN_BLIT_SOURCE_HEIGHT, rect.height(),
                          SCREEN_BLIT_DESTINATION_X, rect.x() + dx,
                          SCREEN_BLIT_DESTINATION_Y, rect.y() + dy,
                          SCREEN_BLIT_DESTINATION_WIDTH, rect.width(),
                          SCREEN_BLIT_DESTINATION_HEIGHT, rect.height(),
                          SCREEN_BLIT_END };

        // queue blit operation
        errno = 0;
        result = screen_blit(mContext, currentBuffer.nativeBuffer(), previousBuffer.nativeBuffer(), attribs);
        if (result != 0) {
            qFatal("QBBWindow: failed to blit buffers, errno=%d", errno);
        }
    }

    // check if flush requested
    if (flush) {

        // wait for all blits to complete
        errno = 0;
        result = screen_flush_blits(mContext, SCREEN_WAIT_IDLE);
        if (result != 0) {
            qFatal("QBBWindow: failed to flush blits, errno=%d", errno);
        }

        // buffer was modified outside the CPU
        currentBuffer.invalidateInCache();
    }
}

int QBBWindow::platformWindowFormatToNativeFormat(const QPlatformWindowFormat &format)
{
    // extract size of colour channels from window format
    int redSize = format.redBufferSize();
    if (redSize == -1) {
        qFatal("QBBWindow: red size not defined");
    }

    int greenSize = format.greenBufferSize();
    if (greenSize == -1) {
        qFatal("QBBWindow: green size not defined");
    }

    int blueSize = format.blueBufferSize();
    if (blueSize == -1) {
        qFatal("QBBWindow: blue size not defined");
    }

    // select matching native format
    if (redSize == 5 && greenSize == 6 && blueSize == 5) {
        return SCREEN_FORMAT_RGB565;
    } else if (redSize == 8 && greenSize == 8 && blueSize == 8) {
        return SCREEN_FORMAT_RGBA8888;
    } else {
        qFatal("QBBWindow: unsupported pixel format");
        return 0;
    }
}

QT_END_NAMESPACE