// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only

#include "qwindowsdirect2dbackingstore.h"
#include "qwindowsdirect2dplatformpixmap.h"
#include "qwindowsdirect2dintegration.h"
#include "qwindowsdirect2dcontext.h"
#include "qwindowsdirect2dpaintdevice.h"
#include "qwindowsdirect2dbitmap.h"
#include "qwindowsdirect2ddevicecontext.h"
#include "qwindowsdirect2dwindow.h"

#include "qwindowscontext.h"

#include <QtGui/qpainter.h>
#include <QtGui/qwindow.h>
#include <QtCore/qdebug.h>

QT_BEGIN_NAMESPACE

/*!
    \class QWindowsDirect2DBackingStore
    \brief Backing store for windows.
    \internal
*/

static inline QWindowsDirect2DPlatformPixmap *platformPixmap(QPixmap *p)
{
    return static_cast<QWindowsDirect2DPlatformPixmap *>(p->handle());
}

static inline QWindowsDirect2DBitmap *bitmap(QPixmap *p)
{
    return platformPixmap(p)->bitmap();
}

static inline QWindowsDirect2DWindow *nativeWindow(QWindow *window)
{
    return static_cast<QWindowsDirect2DWindow *>(window->handle());
}

QWindowsDirect2DBackingStore::QWindowsDirect2DBackingStore(QWindow *window)
    : QPlatformBackingStore(window)
{
}

QWindowsDirect2DBackingStore::~QWindowsDirect2DBackingStore()
{
}

void QWindowsDirect2DBackingStore::beginPaint(const QRegion &region)
{
    QPixmap *pixmap = nativeWindow(window())->pixmap();
    bitmap(pixmap)->deviceContext()->begin();

    QPainter painter(pixmap);
    QColor clear(Qt::transparent);

    painter.setCompositionMode(QPainter::CompositionMode_Source);

    for (const QRect &r : region)
        painter.fillRect(r, clear);
}

void QWindowsDirect2DBackingStore::endPaint()
{
    bitmap(nativeWindow(window())->pixmap())->deviceContext()->end();
}

QPaintDevice *QWindowsDirect2DBackingStore::paintDevice()
{
    return nativeWindow(window())->pixmap();
}

void QWindowsDirect2DBackingStore::flush(QWindow *targetWindow, const QRegion &region, const QPoint &offset)
{
    if (targetWindow != window()) {
        QSharedPointer<QWindowsDirect2DBitmap> copy(nativeWindow(window())->copyBackBuffer());
        nativeWindow(targetWindow)->flush(copy.data(), region, offset);
    }

    nativeWindow(targetWindow)->present(region);
}

void QWindowsDirect2DBackingStore::resize(const QSize &size, const QRegion &region)
{
    QPixmap old = nativeWindow(window())->pixmap()->copy();

    nativeWindow(window())->resizeSwapChain(size);
    QPixmap *newPixmap = nativeWindow(window())->pixmap();

    if (!old.isNull()) {
        for (const QRect &rect : region)
            platformPixmap(newPixmap)->copy(old.handle(), rect);
    }
}

QImage QWindowsDirect2DBackingStore::toImage() const
{
    return nativeWindow(window())->pixmap()->toImage();
}

QT_END_NAMESPACE