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#include "qeglfshooks.h"

#include <ui/DisplayInfo.h>
#include <ui/FramebufferNativeWindow.h>
#include <gui/SurfaceComposerClient.h>
#include <fcntl.h>
#include <unistd.h>
#include <linux/fb.h>
#include <sys/ioctl.h>

using namespace android;

QT_BEGIN_NAMESPACE

class QEglFSPandaHooks : public QEglFSHooks
{
public:
    QEglFSPandaHooks();
    virtual EGLNativeWindowType createNativeWindow(const QSize &size, const QSurfaceFormat &format);
    virtual QSize screenSize() const;
    virtual int screenDepth() const;
    virtual bool filterConfig(EGLDisplay display, EGLConfig config) const;

private:
    EGLNativeWindowType createNativeWindowSurfaceFlinger(const QSize &size, const QSurfaceFormat &format);
    EGLNativeWindowType createNativeWindowFramebuffer(const QSize &size, const QSurfaceFormat &format);

    void ensureFramebufferNativeWindowCreated();

    // androidy things
    sp<android::SurfaceComposerClient> mSession;
    sp<android::SurfaceControl> mControl;
    sp<android::Surface> mAndroidSurface;

    sp<android::FramebufferNativeWindow> mFramebufferNativeWindow;
    EGLint mFramebufferVisualId;

    bool mUseFramebuffer;
};

QEglFSPandaHooks::QEglFSPandaHooks()
    : mFramebufferVisualId(EGL_DONT_CARE)
{
    mUseFramebuffer = qgetenv("QT_QPA_EGLFS_NO_SURFACEFLINGER").toInt();
}

void QEglFSPandaHooks::ensureFramebufferNativeWindowCreated()
{
    if (mFramebufferNativeWindow.get())
        return;
    mFramebufferNativeWindow = new FramebufferNativeWindow();
    framebuffer_device_t const *fbDev = mFramebufferNativeWindow->getDevice();
    if (!fbDev)
        qFatal("Failed to get valid FramebufferNativeWindow, no way to create EGL surfaces");

    ANativeWindow *window = mFramebufferNativeWindow.get();

    window->query(window, NATIVE_WINDOW_FORMAT, &mFramebufferVisualId);
}

EGLNativeWindowType QEglFSPandaHooks::createNativeWindow(const QSize &size, const QSurfaceFormat &format)
{
    return mUseFramebuffer ? createNativeWindowFramebuffer(size, format) : createNativeWindowSurfaceFlinger(size, format);
}

EGLNativeWindowType QEglFSPandaHooks::createNativeWindowFramebuffer(const QSize &size, const QSurfaceFormat &)
{
    Q_UNUSED(size);
    ensureFramebufferNativeWindowCreated();
    return mFramebufferNativeWindow.get();
}

EGLNativeWindowType QEglFSPandaHooks::createNativeWindowSurfaceFlinger(const QSize &size, const QSurfaceFormat &)
{
    Q_UNUSED(size);

    mSession = new SurfaceComposerClient();
    DisplayInfo dinfo;
    int status=0;
    status = mSession->getDisplayInfo(0, &dinfo);
    mControl = mSession->createSurface(
            0, dinfo.w, dinfo.h, PIXEL_FORMAT_RGB_888);
    SurfaceComposerClient::openGlobalTransaction();
    mControl->setLayer(0x40000000);
//    mControl->setAlpha(1);
    SurfaceComposerClient::closeGlobalTransaction();
    mAndroidSurface = mControl->getSurface();

    EGLNativeWindowType eglWindow = mAndroidSurface.get();
    return eglWindow;
}

bool QEglFSPandaHooks::filterConfig(EGLDisplay display, EGLConfig config) const
{
    if (!mUseFramebuffer)
        return true;

    const_cast<QEglFSPandaHooks *>(this)->ensureFramebufferNativeWindowCreated();

    if (mFramebufferVisualId == EGL_DONT_CARE)
        return true;

    EGLint nativeVisualId = 0;
    eglGetConfigAttrib(display, config, EGL_NATIVE_VISUAL_ID, &nativeVisualId);

    return nativeVisualId == mFramebufferVisualId;
}

QSize  QEglFSPandaHooks::screenSize() const
{
    static QSize size;

    if (size.isEmpty()) {
        int width = qgetenv("QT_QPA_EGLFS_WIDTH").toInt();
        int height = qgetenv("QT_QPA_EGLFS_HEIGHT").toInt();

        if (width && height) {
            // no need to read fb0
            size.setWidth(width);
            size.setHeight(height);
            return size;
        }

        struct fb_var_screeninfo vinfo;
        int fd = open("/dev/graphics/fb0", O_RDONLY);

        if (fd != -1) {
            if (ioctl(fd, FBIOGET_VSCREENINFO, &vinfo) == -1)
                qWarning("Could not query variable screen info.");
            else
                size = QSize(vinfo.xres, vinfo.yres);

            close(fd);
        } else {
            qWarning("Failed to open /dev/graphics/fb0 to detect screen resolution.");
        }

        // override fb0 from environment var setting
        if (width)
            size.setWidth(width);
        if (height)
            size.setHeight(height);
    }

    return size;
}

int QEglFSPandaHooks::screenDepth() const
{
    static int depth = qgetenv("QT_QPA_EGLFS_DEPTH").toInt();

    if (depth == 0) {
        struct fb_var_screeninfo vinfo;
        int fd = open("/dev/graphics/fb0", O_RDONLY);

        if (fd != -1) {
            if (ioctl(fd, FBIOGET_VSCREENINFO, &vinfo) == -1)
                qWarning("Could not query variable screen info.");
            else
                depth = vinfo.bits_per_pixel;

            close(fd);
        } else {
            qWarning("Failed to open /dev/graphics/fb0 to detect screen depth.");
        }
    }

    return depth == 0 ? 32 : depth;
}

static QEglFSPandaHooks eglFSPandaHooks;
QEglFSHooks *platformHooks = &eglFSPandaHooks;

QT_END_NAMESPACE