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#include "qmirclientglcontext.h"
#include "qmirclientlogging.h"
#include "qmirclientwindow.h"

#include <QOpenGLFramebufferObject>
#include <QtEglSupport/private/qeglconvenience_p.h>
#include <QtEglSupport/private/qeglpbuffer_p.h>
#include <QtGui/private/qopenglcontext_p.h>

Q_LOGGING_CATEGORY(mirclientGraphics, "qt.qpa.mirclient.graphics", QtWarningMsg)

namespace {

void printEglConfig(EGLDisplay display, EGLConfig config)
{
    Q_ASSERT(display != EGL_NO_DISPLAY);
    Q_ASSERT(config != nullptr);

    const char *string = eglQueryString(display, EGL_VENDOR);
    qCDebug(mirclientGraphics, "EGL vendor: %s", string);

    string = eglQueryString(display, EGL_VERSION);
    qCDebug(mirclientGraphics, "EGL version: %s", string);

    string = eglQueryString(display, EGL_EXTENSIONS);
    qCDebug(mirclientGraphics, "EGL extensions: %s", string);

    qCDebug(mirclientGraphics, "EGL configuration attributes:");
    q_printEglConfig(display, config);
}

} // anonymous namespace

QMirClientOpenGLContext::QMirClientOpenGLContext(const QSurfaceFormat &format, QPlatformOpenGLContext *share,
                                         EGLDisplay display)
    : QEGLPlatformContext(format, share, display, 0)
{
    if (mirclientGraphics().isDebugEnabled()) {
        printEglConfig(display, eglConfig());
    }
}

static bool needsFBOReadBackWorkaround()
{
    static bool set = false;
    static bool needsWorkaround = false;

    if (Q_UNLIKELY(!set)) {
        const char *rendererString = reinterpret_cast<const char *>(glGetString(GL_RENDERER));
        needsWorkaround = qstrncmp(rendererString, "Mali-400", 8) == 0
                          || qstrncmp(rendererString, "Mali-T7", 7) == 0
                          || qstrncmp(rendererString, "PowerVR Rogue G6200", 19) == 0;
        set = true;
    }

    return needsWorkaround;
}

bool QMirClientOpenGLContext::makeCurrent(QPlatformSurface* surface)
{
    const bool ret = QEGLPlatformContext::makeCurrent(surface);

    if (Q_LIKELY(ret)) {
        QOpenGLContextPrivate *ctx_d = QOpenGLContextPrivate::get(context());
        if (!ctx_d->workaround_brokenFBOReadBack && needsFBOReadBackWorkaround()) {
            ctx_d->workaround_brokenFBOReadBack = true;
        }
    }
    return ret;
}

// Following method used internally in the base class QEGLPlatformContext to access
// the egl surface of a QPlatformSurface/QMirClientWindow
EGLSurface QMirClientOpenGLContext::eglSurfaceForPlatformSurface(QPlatformSurface *surface)
{
    if (surface->surface()->surfaceClass() == QSurface::Window) {
        return static_cast<QMirClientWindow *>(surface)->eglSurface();
    } else {
        return static_cast<QEGLPbuffer *>(surface)->pbuffer();
    }
}

void QMirClientOpenGLContext::swapBuffers(QPlatformSurface* surface)
{
    QEGLPlatformContext::swapBuffers(surface);

    if (surface->surface()->surfaceClass() == QSurface::Window) {
        // notify window on swap completion
        auto platformWindow = static_cast<QMirClientWindow *>(surface);
        platformWindow->onSwapBuffersDone();
    }
}