// Copyright (C) 2017 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only

#include "waylandeglclientbufferintegration_p.h"

#include <QtWaylandCompositor/QWaylandCompositor>
#include <qpa/qplatformnativeinterface.h>
#include <QtOpenGL/QOpenGLTexture>
#include <QtGui/QGuiApplication>
#include <QtGui/QOpenGLContext>
#include <QtGui/QOffscreenSurface>
#include <qpa/qplatformscreen.h>
#include <QtGui/QWindow>
#include <QtCore/QPointer>
#include <QDebug>

#include <QMutex>
#include <QMutexLocker>
#include <QVarLengthArray>
#include <QtCore/private/qcore_unix_p.h>
#include <QtGui/private/qeglstreamconvenience_p.h>

#ifndef GL_TEXTURE_EXTERNAL_OES
#define GL_TEXTURE_EXTERNAL_OES     0x8D65
#endif

#ifndef EGL_WAYLAND_BUFFER_WL
#define EGL_WAYLAND_BUFFER_WL       0x31D5
#endif

#ifndef EGL_WAYLAND_EGLSTREAM_WL
#define EGL_WAYLAND_EGLSTREAM_WL    0x334B
#endif

#ifndef EGL_WAYLAND_PLANE_WL
#define EGL_WAYLAND_PLANE_WL        0x31D6
#endif

#ifndef EGL_WAYLAND_Y_INVERTED_WL
#define EGL_WAYLAND_Y_INVERTED_WL   0x31DB
#endif

#ifndef EGL_TEXTURE_RGB
#define EGL_TEXTURE_RGB             0x305D
#endif

#ifndef EGL_TEXTURE_RGBA
#define EGL_TEXTURE_RGBA            0x305E
#endif

#ifndef EGL_TEXTURE_EXTERNAL_WL
#define EGL_TEXTURE_EXTERNAL_WL     0x31DA
#endif

#ifndef EGL_TEXTURE_Y_U_V_WL
#define EGL_TEXTURE_Y_U_V_WL        0x31D7
#endif

#ifndef EGL_TEXTURE_Y_UV_WL
#define EGL_TEXTURE_Y_UV_WL         0x31D8
#endif

#ifndef EGL_TEXTURE_Y_XUXV_WL
#define EGL_TEXTURE_Y_XUXV_WL       0x31D9
#endif

#ifndef EGL_PLATFORM_X11_KHR
#define EGL_PLATFORM_X11_KHR        0x31D5
#endif

/* Needed for compatibility with Mesa older than 10.0. */
typedef EGLBoolean (EGLAPIENTRYP PFNEGLQUERYWAYLANDBUFFERWL_compat) (EGLDisplay dpy, struct wl_resource *buffer, EGLint attribute, EGLint *value);

#ifndef EGL_WL_bind_wayland_display
typedef EGLBoolean (EGLAPIENTRYP PFNEGLBINDWAYLANDDISPLAYWL) (EGLDisplay dpy, struct wl_display *display);
typedef EGLBoolean (EGLAPIENTRYP PFNEGLUNBINDWAYLANDDISPLAYWL) (EGLDisplay dpy, struct wl_display *display);
#endif

#ifndef EGL_KHR_image
typedef EGLImageKHR (EGLAPIENTRYP PFNEGLCREATEIMAGEKHRPROC) (EGLDisplay dpy, EGLContext ctx, EGLenum target, EGLClientBuffer buffer, const EGLint *attrib_list);
typedef EGLBoolean (EGLAPIENTRYP PFNEGLDESTROYIMAGEKHRPROC) (EGLDisplay dpy, EGLImageKHR image);
#endif

#ifndef GL_OES_EGL_image
typedef void (GL_APIENTRYP PFNGLEGLIMAGETARGETTEXTURE2DOESPROC) (GLenum target, GLeglImageOES image);
typedef void (GL_APIENTRYP PFNGLEGLIMAGETARGETRENDERBUFFERSTORAGEOESPROC) (GLenum target, GLeglImageOES image);
#endif

QT_BEGIN_NAMESPACE

static const char *
egl_error_string(EGLint code)
{
#define MYERRCODE(x) case x: return #x;
    switch (code) {
    MYERRCODE(EGL_SUCCESS)
    MYERRCODE(EGL_NOT_INITIALIZED)
    MYERRCODE(EGL_BAD_ACCESS)
    MYERRCODE(EGL_BAD_ALLOC)
    MYERRCODE(EGL_BAD_ATTRIBUTE)
    MYERRCODE(EGL_BAD_CONTEXT)
    MYERRCODE(EGL_BAD_CONFIG)
    MYERRCODE(EGL_BAD_CURRENT_SURFACE)
    MYERRCODE(EGL_BAD_DISPLAY)
    MYERRCODE(EGL_BAD_SURFACE)
    MYERRCODE(EGL_BAD_MATCH)
    MYERRCODE(EGL_BAD_PARAMETER)
    MYERRCODE(EGL_BAD_NATIVE_PIXMAP)
    MYERRCODE(EGL_BAD_NATIVE_WINDOW)
    MYERRCODE(EGL_CONTEXT_LOST)
    default:
        return "unknown";
    }
#undef MYERRCODE
}

struct BufferState
{
    BufferState() = default;

    enum EglMode {
        ModeUninitialized,
        ModeEGLImage,
        ModeEGLStream
    };

    EGLint egl_format = EGL_TEXTURE_RGBA;
    QVarLengthArray<EGLImageKHR, 3> egl_images;
    QOpenGLTexture *textures[3] = {nullptr, nullptr, nullptr};
    QOpenGLContext *texturesContext[3] = {nullptr, nullptr, nullptr};
    QMetaObject::Connection texturesAboutToBeDestroyedConnection[3] = {QMetaObject::Connection(), QMetaObject::Connection(), QMetaObject::Connection()};
    QMutex texturesLock;

    EGLStreamKHR egl_stream = EGL_NO_STREAM_KHR;

    bool isYInverted = true;
    QSize size;
    EglMode eglMode = ModeUninitialized;
};

class WaylandEglClientBufferIntegrationPrivate
{
public:
    WaylandEglClientBufferIntegrationPrivate();

    void initBuffer(WaylandEglClientBuffer *buffer);
    void initEglTexture(WaylandEglClientBuffer *buffer, EGLint format);
    bool ensureContext();
    bool initEglStream(WaylandEglClientBuffer *buffer, struct ::wl_resource *bufferHandle);
    void setupBufferAndCleanup(BufferState *bs, QOpenGLTexture *texture, int plane);
    void handleEglstreamTexture(WaylandEglClientBuffer *buffer, wl_resource *bufferHandle);
    void registerBuffer(struct ::wl_resource *buffer, BufferState state);
    void deleteGLTextureWhenPossible(QOpenGLTexture *texture, QOpenGLContext *ctx);
    void deleteOrphanedTextures();
    void deleteSpecificOrphanedTexture(QOpenGLTexture *texture);

    EGLDisplay egl_display = EGL_NO_DISPLAY;
    bool display_bound = false;
    ::wl_display *wlDisplay = nullptr;
    QOffscreenSurface *offscreenSurface = nullptr;
    QOpenGLContext *localContext = nullptr;

    QMutex orphanedTexturesLock;
    QList<QOpenGLTexture *> orphanedTextures;
    QList<QMetaObject::Connection> orphanedTexturesAboutToBeDestroyedConnection;


    PFNEGLBINDWAYLANDDISPLAYWL egl_bind_wayland_display = nullptr;
    PFNEGLUNBINDWAYLANDDISPLAYWL egl_unbind_wayland_display = nullptr;
    PFNEGLQUERYWAYLANDBUFFERWL_compat egl_query_wayland_buffer = nullptr;

    PFNEGLCREATEIMAGEKHRPROC egl_create_image = nullptr;
    PFNEGLDESTROYIMAGEKHRPROC egl_destroy_image = nullptr;

    PFNGLEGLIMAGETARGETTEXTURE2DOESPROC gl_egl_image_target_texture_2d = nullptr;

    QEGLStreamConvenience *funcs = nullptr;
    static WaylandEglClientBufferIntegrationPrivate *get(WaylandEglClientBufferIntegration *integration) {
        return shuttingDown ? nullptr : integration->d_ptr.data();
    }

    static bool shuttingDown;
};

bool WaylandEglClientBufferIntegrationPrivate::shuttingDown = false;

WaylandEglClientBufferIntegrationPrivate::WaylandEglClientBufferIntegrationPrivate()
{
}

void WaylandEglClientBufferIntegrationPrivate::initBuffer(WaylandEglClientBuffer *buffer)
{
    EGLint format;

    if (egl_query_wayland_buffer(egl_display, buffer->waylandBufferHandle(), EGL_TEXTURE_FORMAT, &format))
        initEglTexture(buffer, format);
}

void WaylandEglClientBufferIntegrationPrivate::initEglTexture(WaylandEglClientBuffer *buffer, EGLint format)
{
// Non-streaming case

    // Resolving GL functions may need a context current, so do it only here.
    if (!gl_egl_image_target_texture_2d)
        gl_egl_image_target_texture_2d = reinterpret_cast<PFNGLEGLIMAGETARGETTEXTURE2DOESPROC>(eglGetProcAddress("glEGLImageTargetTexture2DOES"));

    if (!gl_egl_image_target_texture_2d) {
        qCWarning(qLcWaylandCompositorHardwareIntegration)
                << "BindTextureToBuffer() failed. Could not find glEGLImageTargetTexture2DOES.";
        return;
    }

    BufferState &state = *buffer->d;
    state.egl_format = format;
    state.eglMode = BufferState::ModeEGLImage;

#if defined(EGL_WAYLAND_Y_INVERTED_WL)
    EGLint isYInverted;
    EGLBoolean ret = egl_query_wayland_buffer(egl_display, buffer->waylandBufferHandle(), EGL_WAYLAND_Y_INVERTED_WL, &isYInverted);
    // Yes, this looks strange, but the specification says that EGL_FALSE return
    // value (not supported) should be treated the same as EGL_TRUE return value
    // and EGL_TRUE in value.
    state.isYInverted = (ret == EGL_FALSE || isYInverted == EGL_TRUE);
#endif

    int planes = 1;

    switch (format) {
    default:
    case EGL_TEXTURE_RGB:
    case EGL_TEXTURE_RGBA:
    case EGL_TEXTURE_EXTERNAL_WL:
        planes = 1;
        break;
    case EGL_TEXTURE_Y_UV_WL:
        planes = 2;
        break;
    case EGL_TEXTURE_Y_U_V_WL:
        planes = 3;
        break;
    case EGL_TEXTURE_Y_XUXV_WL:
        planes = 2;
        break;
    }

    for (int i = 0; i < planes; i++) {
        EGLint attribs[5] = { EGL_WAYLAND_PLANE_WL, i, EGL_NONE };
#ifdef EGL_EXT_protected_content
        if (buffer->isProtected()) {
            attribs[2] = EGL_PROTECTED_CONTENT_EXT;
            attribs[3] = EGL_TRUE;
            attribs[4] = EGL_NONE;
        }
#endif
        EGLImageKHR image = egl_create_image(egl_display,
                                             EGL_NO_CONTEXT,
                                             EGL_WAYLAND_BUFFER_WL,
                                             buffer->waylandBufferHandle(),
                                             attribs);

        if (image == EGL_NO_IMAGE_KHR) {
            qCWarning(qLcWaylandCompositorHardwareIntegration)
                    << "Failed to create EGL image for plane" << i;
        }

        state.egl_images << image;

        QMutexLocker locker(&state.texturesLock);
        state.textures[i] = nullptr;
    }
}

bool WaylandEglClientBufferIntegrationPrivate::ensureContext()
{
    bool localContextNeeded = false;
    if (!QOpenGLContext::currentContext()) {
        if (!localContext && QOpenGLContext::globalShareContext()) {
            localContext = new QOpenGLContext;
            localContext->setShareContext(QOpenGLContext::globalShareContext());
            localContext->create();
        }
        if (localContext) {
            if (!offscreenSurface) {
                offscreenSurface = new QOffscreenSurface;
                offscreenSurface->setFormat(localContext->format());
                offscreenSurface->create();
            }
            localContext->makeCurrent(offscreenSurface);
            localContextNeeded = true;
        }
    }
    return localContextNeeded;
}


void WaylandEglClientBufferIntegrationPrivate::setupBufferAndCleanup(BufferState *bs, QOpenGLTexture *texture, int plane)
{
    QMutexLocker locker(&bs->texturesLock);

    bs->textures[plane] = texture;
    bs->texturesContext[plane] = QOpenGLContext::currentContext();

    Q_ASSERT(bs->texturesContext[plane] != nullptr);

    qCDebug(qLcWaylandCompositorHardwareIntegration)
            << Q_FUNC_INFO
            << "(egl) creating a cleanup-lambda for QOpenGLContext::aboutToBeDestroyed!"
            << ", texture: " << bs->textures[plane]
            << ", ctx: " << (void*)bs->texturesContext[plane];

    bs->texturesAboutToBeDestroyedConnection[plane] =
            QObject::connect(bs->texturesContext[plane], &QOpenGLContext::aboutToBeDestroyed,
                             bs->texturesContext[plane], [bs, plane]() {

        QMutexLocker locker(&bs->texturesLock);

        // See above lock - there is a chance that this has already been removed from textures[plane]!
        // Furthermore, we can trust that all the rest (e.g. disconnect) has also been properly executed!
        if (bs->textures[plane] == nullptr)
            return;

        delete bs->textures[plane];

        qCDebug(qLcWaylandCompositorHardwareIntegration)
                << Q_FUNC_INFO
                << "texture deleted due to QOpenGLContext::aboutToBeDestroyed!"
                << "Pointer (now dead) was:" << (void*)(bs->textures[plane])
                << "  Associated context (about to die too) is: " << (void*)(bs->texturesContext[plane]);

        bs->textures[plane] = nullptr;
        bs->texturesContext[plane] = nullptr;

        QObject::disconnect(bs->texturesAboutToBeDestroyedConnection[plane]);
        bs->texturesAboutToBeDestroyedConnection[plane] = QMetaObject::Connection();

    }, Qt::DirectConnection);
}

bool WaylandEglClientBufferIntegrationPrivate::initEglStream(WaylandEglClientBuffer *buffer, wl_resource *bufferHandle)
{
    BufferState &state = *buffer->d;
    state.egl_format = EGL_TEXTURE_EXTERNAL_WL;
    state.isYInverted = false;

    EGLNativeFileDescriptorKHR streamFd = EGL_NO_FILE_DESCRIPTOR_KHR;

    if (egl_query_wayland_buffer(egl_display, bufferHandle, EGL_WAYLAND_BUFFER_WL, &streamFd)) {
        state.egl_stream = funcs->create_stream_from_file_descriptor(egl_display, streamFd);
        close(streamFd);
    } else {
        EGLAttrib stream_attribs[] = {
            EGL_WAYLAND_EGLSTREAM_WL, (EGLAttrib)bufferHandle,
            EGL_NONE
        };
        state.egl_stream = funcs->create_stream_attrib_nv(egl_display, stream_attribs);
    }

    if (state.egl_stream == EGL_NO_STREAM_KHR) {
        qCWarning(qLcWaylandCompositorHardwareIntegration, "%s:%d: eglCreateStreamFromFileDescriptorKHR failed: 0x%x", Q_FUNC_INFO, __LINE__, eglGetError());
        return false;
    }
    state.eglMode = BufferState::ModeEGLStream;

    if (!QOpenGLContext::currentContext()) {
        qCWarning(qLcWaylandCompositorHardwareIntegration)
                << "EglClientBufferIntegration: creating texture with no current context";
        return false;
    }

    auto texture = new QOpenGLTexture(static_cast<QOpenGLTexture::Target>(GL_TEXTURE_EXTERNAL_OES));
    texture->create();
    setupBufferAndCleanup(buffer->d, texture, 0);

    qCDebug(qLcWaylandCompositorHardwareIntegration)
            << " NEW texture! It's pointer and ctx pointer: "
            << (void*)state.textures[0] << "; " << (void*)state.texturesContext[0];

    texture->bind();

    auto newStream = funcs->stream_consumer_gltexture(egl_display, state.egl_stream);
    if (!newStream) {
        EGLint code = eglGetError();
        qCWarning(qLcWaylandCompositorHardwareIntegration) << "Could not initialize EGLStream:" << egl_error_string(code) << Qt::hex << (long)code;
        funcs->destroy_stream(egl_display, state.egl_stream);
        state.egl_stream = EGL_NO_STREAM_KHR;
        return false;
    }
    return true;
}

void WaylandEglClientBufferIntegrationPrivate::handleEglstreamTexture(WaylandEglClientBuffer *buffer, struct ::wl_resource *bufferHandle)
{
    bool usingLocalContext = ensureContext();

    if (buffer->d->eglMode == BufferState::ModeUninitialized) {
        bool streamOK = initEglStream(buffer, bufferHandle);
        if (!streamOK)
            return;
    }

    BufferState &state = *buffer->d;
    auto texture = state.textures[0];

    // EGLStream requires calling acquire on every frame.
    texture->bind();
    EGLint stream_state;
    funcs->query_stream(egl_display, state.egl_stream, EGL_STREAM_STATE_KHR, &stream_state);

    if (stream_state == EGL_STREAM_STATE_NEW_FRAME_AVAILABLE_KHR) {
        if (funcs->stream_consumer_acquire(egl_display, state.egl_stream) != EGL_TRUE)
            qCWarning(qLcWaylandCompositorHardwareIntegration,
                      "%s:%d: eglStreamConsumerAcquireKHR failed: 0x%x", Q_FUNC_INFO, __LINE__,
                      eglGetError());
    }

    if (usingLocalContext)
        localContext->doneCurrent();
}

void WaylandEglClientBufferIntegrationPrivate::deleteGLTextureWhenPossible(QOpenGLTexture *texture, QOpenGLContext *ctx) {
    QMutexLocker locker(&orphanedTexturesLock);

    Q_ASSERT(ctx != nullptr);
    Q_ASSERT(orphanedTextures.size() == orphanedTexturesAboutToBeDestroyedConnection.size());

    qCDebug(qLcWaylandCompositorHardwareIntegration)
            << Q_FUNC_INFO << " got texture and ctx to be deleted!"
            << (void*)texture << "; " << (void*)ctx;

    orphanedTextures << texture;
    orphanedTexturesAboutToBeDestroyedConnection << QObject::connect(ctx, &QOpenGLContext::aboutToBeDestroyed,
                                                                     ctx, [this, texture]() {
        this->deleteSpecificOrphanedTexture(texture);
    }, Qt::DirectConnection);
}

void WaylandEglClientBufferIntegrationPrivate::deleteOrphanedTextures()
{
    Q_ASSERT(QOpenGLContext::currentContext());

    QMutexLocker locker(&orphanedTexturesLock);

    for (int i=0; i < orphanedTextures.size(); i++) {
        qCDebug(qLcWaylandCompositorHardwareIntegration)
                << Q_FUNC_INFO << " about to delete a texture: "
                << (void*)orphanedTextures[i];
    }

    qDeleteAll(orphanedTextures);

    for (QMetaObject::Connection con : orphanedTexturesAboutToBeDestroyedConnection)
        QObject::disconnect(con);

    orphanedTexturesAboutToBeDestroyedConnection.clear();
    orphanedTextures.clear();
}

void WaylandEglClientBufferIntegrationPrivate::deleteSpecificOrphanedTexture(QOpenGLTexture *texture)
{
    Q_ASSERT(orphanedTextures.size() == orphanedTexturesAboutToBeDestroyedConnection.size());

    QMutexLocker locker(&orphanedTexturesLock);

    // In this case, deleteOrphanedTextures was called while we entered (see lock!) this function!
    if (orphanedTextures.length()==0) {
        qCWarning(qLcWaylandCompositorHardwareIntegration)
                << Q_FUNC_INFO
                << "Looks like deleteOrphanedTextures() and this function where called simultaneously!"
                << "This might cause issues!";
        return;
    }

    int i = orphanedTextures.indexOf(texture);
    Q_ASSERT(i!=-1);  // If it isn't empty (see above if), then it should be guaranteed to still contain this texture

    orphanedTextures.removeAt(i);
    QMetaObject::Connection con = orphanedTexturesAboutToBeDestroyedConnection.takeAt(i);

    QObject::disconnect(con);
    delete texture;

    qCDebug(qLcWaylandCompositorHardwareIntegration)
            << Q_FUNC_INFO
            << "texture deleted due to QOpenGLContext::aboutToBeDestroyed!"
            << "Pointer (now dead) was:" << (void*)texture;
}

WaylandEglClientBufferIntegration::WaylandEglClientBufferIntegration()
    : d_ptr(new WaylandEglClientBufferIntegrationPrivate)
{
}

WaylandEglClientBufferIntegration::~WaylandEglClientBufferIntegration()
{
    WaylandEglClientBufferIntegrationPrivate::shuttingDown = true;
    Q_D(WaylandEglClientBufferIntegration);
    if (d->egl_unbind_wayland_display && d->display_bound) {
        Q_ASSERT(d->wlDisplay);
        if (!d->egl_unbind_wayland_display(d->egl_display, d->wlDisplay))
            qCWarning(qLcWaylandCompositorHardwareIntegration) << "eglUnbindWaylandDisplayWL failed";
    }
}

void WaylandEglClientBufferIntegration::initializeHardware(struct wl_display *display)
{
    Q_D(WaylandEglClientBufferIntegration);

    const bool ignoreBindDisplay = !qgetenv("QT_WAYLAND_IGNORE_BIND_DISPLAY").isEmpty();

    QPlatformNativeInterface *nativeInterface = QGuiApplication::platformNativeInterface();
    if (!nativeInterface) {
        qCWarning(qLcWaylandCompositorHardwareIntegration)
                << "Failed to initialize EGL display. No native platform interface available.";
        return;
    }

    d->egl_display = nativeInterface->nativeResourceForIntegration("EglDisplay");
    if (!d->egl_display) {
        qCWarning(qLcWaylandCompositorHardwareIntegration)
                << "Failed to initialize EGL display. Could not get EglDisplay for window.";
        return;
    }

    const char *extensionString = eglQueryString(d->egl_display, EGL_EXTENSIONS);
    if ((!extensionString || !strstr(extensionString, "EGL_WL_bind_wayland_display")) && !ignoreBindDisplay) {
        qCWarning(qLcWaylandCompositorHardwareIntegration)
                << "Failed to initialize EGL display. There is no EGL_WL_bind_wayland_display extension.";
        return;
    }

    d->egl_bind_wayland_display = reinterpret_cast<PFNEGLBINDWAYLANDDISPLAYWL>(eglGetProcAddress("eglBindWaylandDisplayWL"));
    d->egl_unbind_wayland_display = reinterpret_cast<PFNEGLUNBINDWAYLANDDISPLAYWL>(eglGetProcAddress("eglUnbindWaylandDisplayWL"));
    if ((!d->egl_bind_wayland_display || !d->egl_unbind_wayland_display) && !ignoreBindDisplay) {
        qCWarning(qLcWaylandCompositorHardwareIntegration)
                << "Failed to initialize EGL display. Could not find eglBindWaylandDisplayWL and eglUnbindWaylandDisplayWL.";
        return;
    }

    d->egl_query_wayland_buffer = reinterpret_cast<PFNEGLQUERYWAYLANDBUFFERWL_compat>(eglGetProcAddress("eglQueryWaylandBufferWL"));
    if (!d->egl_query_wayland_buffer) {
        qCWarning(qLcWaylandCompositorHardwareIntegration)
                << "Failed to initialize EGL display. Could not find eglQueryWaylandBufferWL.";
        return;
    }

    d->egl_create_image = reinterpret_cast<PFNEGLCREATEIMAGEKHRPROC>(eglGetProcAddress("eglCreateImageKHR"));
    d->egl_destroy_image = reinterpret_cast<PFNEGLDESTROYIMAGEKHRPROC>(eglGetProcAddress("eglDestroyImageKHR"));
    if (!d->egl_create_image || !d->egl_destroy_image) {
        qCWarning(qLcWaylandCompositorHardwareIntegration)
                << "Failed to initialize EGL display. Could not find eglCreateImageKHR and eglDestroyImageKHR.";
        return;
    }

    if (d->egl_bind_wayland_display && d->egl_unbind_wayland_display) {
        d->display_bound = d->egl_bind_wayland_display(d->egl_display, display);
        if (!d->display_bound)
            qCDebug(qLcWaylandCompositorHardwareIntegration) << "Wayland display already bound by other client buffer integration.";
        d->wlDisplay = display;
    }

    d->funcs = new QEGLStreamConvenience;
    d->funcs->initialize(d->egl_display);
}

QtWayland::ClientBuffer *WaylandEglClientBufferIntegration::createBufferFor(wl_resource *buffer)
{
    Q_D(WaylandEglClientBufferIntegration);
    int w = -1;
    bool q = d->egl_query_wayland_buffer(d->egl_display, buffer, EGL_WIDTH, &w);
    if (!q || w <= 0)
        return nullptr;
    return new WaylandEglClientBuffer(this, buffer);
}

WaylandEglClientBuffer::WaylandEglClientBuffer(WaylandEglClientBufferIntegration *integration, wl_resource *buffer)
    : ClientBuffer(buffer)
    , m_integration(integration)
{
    auto *p = WaylandEglClientBufferIntegrationPrivate::get(m_integration);
    d = new BufferState;
    if (buffer && !wl_shm_buffer_get(buffer)) {
        EGLint width, height;
        p->egl_query_wayland_buffer(p->egl_display, buffer, EGL_WIDTH, &width);
        p->egl_query_wayland_buffer(p->egl_display, buffer, EGL_HEIGHT, &height);
        d->size = QSize(width, height);

        p->initBuffer(this);
    }
}


WaylandEglClientBuffer::~WaylandEglClientBuffer()
{
    auto *p = WaylandEglClientBufferIntegrationPrivate::get(m_integration);

    if (p) {
        for (auto image : d->egl_images)
            p->egl_destroy_image(p->egl_display, image);

        if (d->egl_stream)
            p->funcs->destroy_stream(p->egl_display, d->egl_stream);


        QMutexLocker locker(&d->texturesLock);

        for (int i=0; i<3; i++) {
            if (d->textures[i] != nullptr) {

                qCDebug(qLcWaylandCompositorHardwareIntegration)
                        << Q_FUNC_INFO << " handing over texture!"
                        << (void*)d->textures[i] << "; " << (void*)d->texturesContext[i]
                        <<  " ... current context might be the same: " << QOpenGLContext::currentContext();

                p->deleteGLTextureWhenPossible(d->textures[i], d->texturesContext[i]);
                d->textures[i] = nullptr;               // in case the aboutToBeDestroyed lambda is called while we where here
                d->texturesContext[i] = nullptr;
                QObject::disconnect(d->texturesAboutToBeDestroyedConnection[i]);
                d->texturesAboutToBeDestroyedConnection[i] = QMetaObject::Connection();
            }
        }
    }

    delete d;
}

static QWaylandBufferRef::BufferFormatEgl formatFromEglFormat(EGLint format) {
    switch (format) {
    case EGL_TEXTURE_RGB:
        return QWaylandBufferRef::BufferFormatEgl_RGB;
    case EGL_TEXTURE_RGBA:
        return QWaylandBufferRef::BufferFormatEgl_RGBA;
    case EGL_TEXTURE_EXTERNAL_WL:
        return QWaylandBufferRef::BufferFormatEgl_EXTERNAL_OES;
    case EGL_TEXTURE_Y_UV_WL:
        return QWaylandBufferRef::BufferFormatEgl_Y_UV;
    case EGL_TEXTURE_Y_U_V_WL:
        return QWaylandBufferRef::BufferFormatEgl_Y_U_V;
    case EGL_TEXTURE_Y_XUXV_WL:
        return QWaylandBufferRef::BufferFormatEgl_Y_XUXV;
    }

    return QWaylandBufferRef::BufferFormatEgl_RGBA;
}

static QOpenGLTexture::TextureFormat openGLFormatFromEglFormat(EGLint format) {
    switch (format) {
    case EGL_TEXTURE_RGB:
        return QOpenGLTexture::RGBFormat;
    case EGL_TEXTURE_RGBA:
        return QOpenGLTexture::RGBAFormat;
    default:
        return QOpenGLTexture::NoFormat;
    }
}

QWaylandBufferRef::BufferFormatEgl WaylandEglClientBuffer::bufferFormatEgl() const
{
    return formatFromEglFormat(d->egl_format);
}

QOpenGLTexture *WaylandEglClientBuffer::toOpenGlTexture(int plane)
{
    auto *p = WaylandEglClientBufferIntegrationPrivate::get(m_integration);
    // At this point we should have a valid OpenGL context, so it's safe to destroy textures
    p->deleteOrphanedTextures();

    if (!m_buffer)
        return nullptr;

    auto texture = d->textures[plane];
    if (d->eglMode == BufferState::ModeEGLStream)
        return texture; // EGLStreams texture is maintained by handle_eglstream_texture()

    const auto target = static_cast<QOpenGLTexture::Target>(d->egl_format == EGL_TEXTURE_EXTERNAL_WL ? GL_TEXTURE_EXTERNAL_OES
                                                                        : GL_TEXTURE_2D);
    if (!texture) {
        texture = new QOpenGLTexture(target);
        texture->setFormat(openGLFormatFromEglFormat(d->egl_format));
        texture->setSize(d->size.width(), d->size.height());
        texture->create();
        p->setupBufferAndCleanup(this->d, texture, plane);
    }

    if (m_textureDirty) {
        m_textureDirty = false;
        texture->bind();
        glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
        p->gl_egl_image_target_texture_2d(target, d->egl_images[plane]);
#ifdef GL_EXT_protected_textures
        if (isProtected())
            glTexParameteri(target, GL_TEXTURE_PROTECTED_EXT, GL_TRUE);
#endif
    }
    return texture;
}

void WaylandEglClientBuffer::setCommitted(QRegion &damage)
{
    ClientBuffer::setCommitted(damage);
    if (d->eglMode == BufferState::ModeEGLStream || d->eglMode == BufferState::ModeUninitialized) {
        auto *p = WaylandEglClientBufferIntegrationPrivate::get(m_integration);
        p->handleEglstreamTexture(this, waylandBufferHandle());
    }
}

bool WaylandEglClientBuffer::isProtected()
{
    if (m_integration && m_buffer)
        return m_integration->isProtected(m_buffer);

    return false;
}


QWaylandSurface::Origin WaylandEglClientBuffer::origin() const
{
    return d->isYInverted ? QWaylandSurface::OriginTopLeft : QWaylandSurface::OriginBottomLeft;
}

quintptr WaylandEglClientBuffer::lockNativeBuffer()
{
    auto *p = WaylandEglClientBufferIntegrationPrivate::get(m_integration);

    if (d->egl_stream != EGL_NO_STREAM_KHR)
        return 0;

    EGLImageKHR image = p->egl_create_image(p->egl_display, EGL_NO_CONTEXT,
                                          EGL_WAYLAND_BUFFER_WL,
                                          m_buffer, nullptr);
    return reinterpret_cast<quintptr>(image);
}

void WaylandEglClientBuffer::unlockNativeBuffer(quintptr native_buffer) const
{
    if (!native_buffer)
        return;

    auto *p = WaylandEglClientBufferIntegrationPrivate::get(m_integration);

    EGLImageKHR image = reinterpret_cast<EGLImageKHR>(native_buffer);
    p->egl_destroy_image(p->egl_display, image);
}

QSize WaylandEglClientBuffer::size() const
{
    return d->size;
}

QT_END_NAMESPACE
