/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtOpenGL module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights.  These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include "qgl.h"
#include <private/qt_x11_p.h>
#include <private/qpixmap_x11_p.h>
#include <private/qgl_p.h>
#include <private/qpaintengine_opengl_p.h>
#include "qgl_egl_p.h"
#include "qcolormap.h"
#include <QDebug>


QT_BEGIN_NAMESPACE

bool QGLFormat::hasOpenGL()
{
    return true;
}

bool QGLFormat::hasOpenGLOverlays()
{
    return false;
}

void qt_egl_add_platform_config(QEglProperties& props, QPaintDevice *device)
{
    if (device->devType() == QInternal::Image)
        props.setPixelFormat(static_cast<QImage *>(device)->format());
}

bool QGLContext::chooseContext(const QGLContext* shareContext)
{
    Q_D(QGLContext);

    if (!device())
        return false;

    int devType = device()->devType();

    // Get the display and initialize it.
    d->eglContext = new QEglContext();
    d->eglContext->setApi(QEgl::OpenGL);
    if (!d->eglContext->openDisplay(device())) {
        delete d->eglContext;
        d->eglContext = 0;
        return false;
    }

    // Construct the configuration we need for this surface.
    QEglProperties configProps;
    qt_egl_set_format(configProps, devType, d->glFormat);
    qt_egl_add_platform_config(configProps, device());
    configProps.setRenderableType(QEgl::OpenGL);

    // Search for a matching configuration, reducing the complexity
    // each time until we get something that matches.
    if (!d->eglContext->chooseConfig(configProps, QEgl::BestPixelFormat)) {
        delete d->eglContext;
        d->eglContext = 0;
        return false;
    }

    // Inform the higher layers about the actual format properties.
    qt_egl_update_format(*(d->eglContext), d->glFormat);

    // Create a new context for the configuration.
    if (!d->eglContext->createContext
            (shareContext ? shareContext->d_func()->eglContext : 0)) {
        delete d->eglContext;
        d->eglContext = 0;
        return false;
    }

#if defined(EGL_VERSION_1_1)
    if (d->glFormat.swapInterval() != -1 && devType == QInternal::Widget)
        eglSwapInterval(d->eglContext->display(), d->glFormat.swapInterval());
#endif

    return true;
}


void QGLContext::reset()
{
    Q_D(QGLContext);
    if (!d->valid)
        return;
    d->cleanup();
    doneCurrent();
    if (d->eglContext) {
        delete d->eglContext;
        d->eglContext = 0;
    }
    d->crWin = false;
    d->sharing = false;
    d->valid = false;
    d->transpColor = QColor();
    d->initDone = false;
    qgl_share_reg()->removeShare(this);
}

void QGLContext::makeCurrent()
{
    Q_D(QGLContext);
    if(!d->valid || !d->eglContext) {
        qWarning("QGLContext::makeCurrent(): Cannot make invalid context current");
        return;
    }

    if (d->eglContext->makeCurrent())
        QGLContextPrivate::setCurrentContext(this);
}

void QGLContext::doneCurrent()
{
    Q_D(QGLContext);
    if (d->eglContext)
        d->eglContext->doneCurrent();

    QGLContextPrivate::setCurrentContext(0);
}


void QGLContext::swapBuffers() const
{
    Q_D(const QGLContext);
    if(!d->valid || !d->eglContext)
        return;

    d->eglContext->swapBuffers();
}

QColor QGLContext::overlayTransparentColor() const
{
    return QColor(0, 0, 0);                // Invalid color
}

uint QGLContext::colorIndex(const QColor &c) const
{
    //### color index doesn't work on egl
    Q_UNUSED(c);
    return 0;
}

void QGLContext::generateFontDisplayLists(const QFont & fnt, int listBase)
{
    Q_UNUSED(fnt);
    Q_UNUSED(listBase);
}

void *QGLContext::getProcAddress(const QString &proc) const
{
    return (void*)eglGetProcAddress(reinterpret_cast<const char *>(proc.toLatin1().data()));
}

void QGLWidget::setMouseTracking(bool enable)
{
    QWidget::setMouseTracking(enable);
}


void QGLWidget::resizeEvent(QResizeEvent *)
{
    Q_D(QGLWidget);
    if (!isValid())
        return;
    makeCurrent();
    if (!d->glcx->initialized())
        glInit();
    resizeGL(width(), height());
    //handle overlay
}

const QGLContext* QGLWidget::overlayContext() const
{
    return 0;
}

void QGLWidget::makeOverlayCurrent()
{
    //handle overlay
}

void QGLWidget::updateOverlayGL()
{
    //handle overlay
}

void QGLWidget::setContext(QGLContext *context, const QGLContext* shareContext, bool deleteOldContext)
{
    Q_D(QGLWidget);
    if (context == 0) {
        qWarning("QGLWidget::setContext: Cannot set null context");
        return;
    }
    if (!context->deviceIsPixmap() && context->device() != this) {
        qWarning("QGLWidget::setContext: Context must refer to this widget");
        return;
    }

    if (d->glcx)
        d->glcx->doneCurrent();
    QGLContext* oldcx = d->glcx;
    d->glcx = context;

    if (parentWidget()) {
        // force creation of delay-created widgets
        parentWidget()->winId();
        if (parentWidget()->x11Info().screen() != x11Info().screen())
            d_func()->xinfo = parentWidget()->d_func()->xinfo;
    }

    // If the application has set WA_TranslucentBackground and not explicitly set
    // the alpha buffer size to zero, modify the format so it have an alpha channel
    QGLFormat& fmt = d->glcx->d_func()->glFormat;
    const bool useArgbVisual = testAttribute(Qt::WA_TranslucentBackground);
    if (useArgbVisual && fmt.alphaBufferSize() == -1)
        fmt.setAlphaBufferSize(1);

    bool createFailed = false;
    if (!d->glcx->isValid()) {
        if (!d->glcx->create(shareContext ? shareContext : oldcx))
            createFailed = true;
    }
    if (createFailed) {
        if (deleteOldContext)
            delete oldcx;
        return;
    }

    if (d->glcx->windowCreated() || d->glcx->deviceIsPixmap()) {
        if (deleteOldContext)
            delete oldcx;
        return;
    }

    bool visible = isVisible();
    if (visible)
        hide();

    XVisualInfo vi;
    memset(&vi, 0, sizeof(XVisualInfo));

    // Check to see if EGL is suggesting an appropriate visual id:
    EGLint nativeVisualId;
    QEglContext* qeglCtx = d->glcx->d_func()->eglContext;
    qeglCtx->configAttrib(EGL_NATIVE_VISUAL_ID, &nativeVisualId);
    vi.visualid = nativeVisualId;

    if (vi.visualid) {
        // EGL has suggested a visual id, so get the rest of the visual info for that id:
        XVisualInfo *chosenVisualInfo;
        int matchingCount = 0;
        chosenVisualInfo = XGetVisualInfo(x11Info().display(), VisualIDMask, &vi, &matchingCount);
        if (chosenVisualInfo) {
#if !defined(QT_NO_XRENDER)
            if (useArgbVisual) {
                // Check to make sure the visual provided by EGL is ARGB
                XRenderPictFormat *format;
                format = XRenderFindVisualFormat(x11Info().display(), chosenVisualInfo->visual);
                if (format->type == PictTypeDirect && format->direct.alphaMask) {
                    qDebug("Using opaque X Visual ID (%d) provided by EGL", (int)vi.visualid);
                    vi = *chosenVisualInfo;
                }
                else {
                    qWarning("Warning: EGL suggested using X visual ID %d for config %d, but this is not ARGB",
                             nativeVisualId, (int)qeglCtx->config());
                    vi.visualid = 0;
                }
            } else
#endif
            {
                qDebug("Using opaque X Visual ID (%d) provided by EGL", (int)vi.visualid);
                vi = *chosenVisualInfo;
            }
            XFree(chosenVisualInfo);
        }
        else {
            qWarning("Warning: EGL suggested using X visual ID %d for config %d, but this seems to be invalid!",
                     nativeVisualId, (int)qeglCtx->config());
            vi.visualid = 0;
        }
    }

    // If EGL does not know the visual ID, so try to select an appropriate one ourselves, first
    // using XRender if we're supposed to have an alpha, then falling back to XGetVisualInfo

    bool useArgb = context->format().alpha() && !context->deviceIsPixmap();
#if !defined(QT_NO_XRENDER)
    if (vi.visualid == 0 && useArgb) {
        // Try to use XRender to find an ARGB visual we can use
        vi.screen  = x11Info().screen();
        vi.depth   = 32;
        vi.c_class = TrueColor;
        XVisualInfo *matchingVisuals;
        int matchingCount = 0;
        matchingVisuals = XGetVisualInfo(x11Info().display(),
                                         VisualScreenMask|VisualDepthMask|VisualClassMask,
                                         &vi, &matchingCount);

        for (int i = 0; i < matchingCount; ++i) {
            XRenderPictFormat *format;
            format = XRenderFindVisualFormat(x11Info().display(), matchingVisuals[i].visual);
            if (format->type == PictTypeDirect && format->direct.alphaMask) {
                vi = matchingVisuals[i];
                qDebug("Using X Visual ID (%d) for ARGB visual as provided by XRender", (int)vi.visualid);
                break;
            }
        }
        XFree(matchingVisuals);
    }
#endif

    if (vi.visualid == 0) {
        EGLint depth;
        qeglCtx->configAttrib(EGL_BUFFER_SIZE, &depth);
        int err;
        err = XMatchVisualInfo(x11Info().display(), x11Info().screen(), depth, TrueColor, &vi);
        if (err == 0) {
            qWarning("Warning: Can't find an X visual which matches the EGL config(%d)'s depth (%d)!",
                     (int)qeglCtx->config(), depth);
            depth = x11Info().depth();
            err = XMatchVisualInfo(x11Info().display(), x11Info().screen(), depth, TrueColor, &vi);
            if (err == 0) {
                qWarning("Error: Couldn't get any matching X visual!");
                return;
            } else
                qWarning("         - Falling back to X11 suggested depth (%d)", depth);
        } else
            qDebug("Using X Visual ID (%d) for EGL provided depth (%d)", (int)vi.visualid, depth);

        // Don't try to use ARGB now unless the visual is 32-bit - even then it might stil fail :-(
        if (useArgb)
            useArgb = vi.depth == 32;
    }

//    qDebug("Visual Info:");
//    qDebug("   bits_per_rgb=%d", vi.bits_per_rgb);
//    qDebug("   red_mask=0x%x", vi.red_mask);
//    qDebug("   green_mask=0x%x", vi.green_mask);
//    qDebug("   blue_mask=0x%x", vi.blue_mask);
//    qDebug("   colormap_size=%d", vi.colormap_size);
//    qDebug("   c_class=%d", vi.c_class);
//    qDebug("   depth=%d", vi.depth);
//    qDebug("   screen=%d", vi.screen);
//    qDebug("   visualid=%d", vi.visualid);

    XSetWindowAttributes a;

    Window p = RootWindow(x11Info().display(), x11Info().screen());
    if (parentWidget())
        p = parentWidget()->winId();

    QColormap colmap = QColormap::instance(vi.screen);
    a.background_pixel = colmap.pixel(palette().color(backgroundRole()));
    a.border_pixel = colmap.pixel(Qt::black);

    unsigned int valueMask = CWBackPixel|CWBorderPixel;
    if(useArgb) {
        a.colormap = XCreateColormap(x11Info().display(), p, vi.visual, AllocNone);
        valueMask |= CWColormap;
    }

    Window w = XCreateWindow(x11Info().display(), p, x(), y(), width(), height(),
                             0, vi.depth, InputOutput, vi.visual, valueMask, &a);

    if (deleteOldContext)
        delete oldcx;
    oldcx = 0;

    create(w); // Create with the ID of the window we've just created


    // Create the EGL surface to draw into.
    if (!d->glcx->d_func()->eglContext->createSurface(this)) {
        delete d->glcx->d_func()->eglContext;
        d->glcx->d_func()->eglContext = 0;
        return;
    }

    d->eglSurfaceWindowId = w; // Remember the window id we created the surface for

    if (visible)
        show();

    XFlush(X11->display);
    d->glcx->setWindowCreated(true);
}

void QGLWidgetPrivate::init(QGLContext *context, const QGLWidget* shareWidget)
{
    Q_Q(QGLWidget);

    initContext(context, shareWidget);

    if(q->isValid() && glcx->format().hasOverlay()) {
        //no overlay
        qWarning("QtOpenGL ES doesn't currently support overlays");
    }
}

bool QGLWidgetPrivate::renderCxPm(QPixmap*)
{
    return false;
}

void QGLWidgetPrivate::cleanupColormaps()
{
}

const QGLColormap & QGLWidget::colormap() const
{
    return d_func()->cmap;
}

void QGLWidget::setColormap(const QGLColormap &)
{
}

void QGLExtensions::init()
{
    static bool init_done = false;

    if (init_done)
        return;
    init_done = true;

    // We need a context current to initialize the extensions.
    QGLWidget tmpWidget;
    tmpWidget.makeCurrent();

    init_extensions();

    tmpWidget.doneCurrent();
}

// Re-creates the EGL surface if the window ID has changed or if force is true
void QGLWidgetPrivate::recreateEglSurface(bool force)
{
    Q_Q(QGLWidget);

    Window currentId = q->winId();

    if ( force || (currentId != eglSurfaceWindowId) ) {
        // The window id has changed so we need to re-create the EGL surface
        if (!glcx->d_func()->eglContext->recreateSurface(q))
            qWarning("Error creating EGL window surface: 0x%x", eglGetError());

        eglSurfaceWindowId = currentId;
    }
}


QGLTexture *QGLContextPrivate::bindTextureFromNativePixmap(QPixmapData* pd, const qint64 key,
                                                           QGLContext::BindOptions options)
{
    Q_Q(QGLContext);

    // The EGL texture_from_pixmap has no facility to invert the y coordinate
    if (!(options & QGLContext::CanFlipNativePixmapBindOption))
        return 0;

    Q_ASSERT(pd->classId() == QPixmapData::X11Class);

    static bool checkedForTFP = false;
    static bool haveTFP = false;

    if (!checkedForTFP) {
        // Check for texture_from_pixmap egl extension
        checkedForTFP = true;
        if (eglContext->hasExtension("EGL_NOKIA_texture_from_pixmap") ||
            eglContext->hasExtension("EGL_EXT_texture_from_pixmap"))
        {
            qDebug("Found texture_from_pixmap EGL extension!");
            haveTFP = true;
        }
    }

    if (!haveTFP)
        return 0;

    QX11PixmapData *pixmapData = static_cast<QX11PixmapData*>(pd);

    bool hasAlpha = pixmapData->hasAlphaChannel();

    // Check to see if the surface is still valid
    if (pixmapData->gl_surface &&
        hasAlpha != (pixmapData->flags & QX11PixmapData::GlSurfaceCreatedWithAlpha))
    {
        // Surface is invalid!
        destroyGlSurfaceForPixmap(pixmapData);
    }

    EGLint pixmapAttribs[] = {
        EGL_TEXTURE_TARGET, EGL_TEXTURE_2D,
        EGL_TEXTURE_FORMAT, hasAlpha ? EGL_TEXTURE_RGBA : EGL_TEXTURE_RGB,
        EGL_NONE
    };
    Q_ASSERT(sizeof(Qt::HANDLE) >= sizeof(EGLSurface)); // Just to make totally sure!
    if (pixmapData->gl_surface == 0)
        pixmapData->gl_surface = (Qt::HANDLE)EGL_NO_SURFACE;
    EGLSurface pixmapSurface = (EGLSurface)pixmapData->gl_surface;
    static EGLConfig pixmapRGBConfig = 0;
    static EGLConfig pixmapRGBAConfig = 0;

    // Check to see if we need to find a config
    if ((hasAlpha && !pixmapRGBAConfig) || (!hasAlpha && !pixmapRGBConfig) ) {
        const EGLint configAttribs[] = {
            EGL_SURFACE_TYPE,           EGL_PIXMAP_BIT,
            EGL_RENDERABLE_TYPE,	EGL_OPENGL_ES2_BIT,
            EGL_DEPTH_SIZE,		0,
            hasAlpha ? EGL_BIND_TO_TEXTURE_RGBA : EGL_BIND_TO_TEXTURE_RGB, EGL_TRUE,
            EGL_NONE
        };

        EGLint configCount = 0;
        eglChooseConfig(eglContext->display(), configAttribs, 0, 256, &configCount);
        if (configCount == 0) {
            haveTFP = false;
            qWarning("bindTextureFromNativePixmap() - Couldn't find a suitable config");
            return 0;
        }

        EGLConfig *configList = new EGLConfig[configCount];
        eglChooseConfig(eglContext->display(), configAttribs, configList, configCount, &configCount);
        Q_ASSERT(configCount);

        // Try to create a pixmap surface for each config until one works
        for (int i = 0; i < configCount; ++i) {
            pixmapSurface = eglCreatePixmapSurface(eglContext->display(), configList[i],
                                                   (EGLNativePixmapType) pixmapData->handle(),
                                                   pixmapAttribs);
            if (pixmapSurface != EGL_NO_SURFACE) {
                // Got one!
                qDebug() << "Found an" << (hasAlpha ? "ARGB" : "RGB")
                         << "config (" << int(configList[i]) << ") to create a pixmap surface";
                if (hasAlpha)
                    pixmapRGBAConfig = configList[i];
                else
                    pixmapRGBConfig = configList[i];
                pixmapData->gl_surface = (Qt::HANDLE)pixmapSurface;
                break;
            }
        }
        delete configList;

        if ((hasAlpha && !pixmapRGBAConfig) || (!hasAlpha && !pixmapRGBConfig) ) {
            qDebug("Couldn't create a pixmap surface with any of the provided configs");
            haveTFP = false;
            return 0;
        }
    }

    if (pixmapSurface == EGL_NO_SURFACE) {
        pixmapSurface = eglCreatePixmapSurface(eglContext->display(),
                                               hasAlpha? pixmapRGBAConfig : pixmapRGBConfig,
                                               (EGLNativePixmapType) pixmapData->handle(),
                                               pixmapAttribs);
        if (pixmapSurface == EGL_NO_SURFACE) {
            qWarning("Failed to create a pixmap surface using config %d",
                        (int)(hasAlpha? pixmapRGBAConfig : pixmapRGBConfig));
            haveTFP = false;
            return 0;
        }
        pixmapData->gl_surface = (Qt::HANDLE)pixmapSurface;
    }

    // Make sure the cleanup hook gets called so we can delete the glx pixmap
    pixmapData->is_cached = true;
    Q_ASSERT(pixmapData->gl_surface);

    GLuint textureId;
    glGenTextures(1, &textureId);
    glEnable(GL_TEXTURE_2D);
    glBindTexture(GL_TEXTURE_2D, textureId);

    // bind the egl pixmap surface to a texture
    EGLBoolean success;
    success = eglBindTexImage(eglContext->display(), pixmapSurface, EGL_BACK_BUFFER);
    if (success == EGL_FALSE) {
        qWarning() << "eglBindTexImage() failed:" << eglContext->errorString(eglGetError());
        eglDestroySurface(eglContext->display(), pixmapSurface);
        pixmapData->gl_surface = (Qt::HANDLE)EGL_NO_SURFACE;
        haveTFP = false;
        return 0;
    }

    QGLTexture *texture = new QGLTexture(q, textureId, GL_TEXTURE_2D, options);
    pixmapData->flags |= QX11PixmapData::InvertedWhenBoundToTexture;

    // We assume the cost of bound pixmaps is zero
    QGLTextureCache::instance()->insert(q, key, texture, 0);

    glBindTexture(GL_TEXTURE_2D, textureId);
    return texture;
}

void QGLContextPrivate::destroyGlSurfaceForPixmap(QPixmapData* pmd)
{
    Q_ASSERT(pmd->classId() == QPixmapData::X11Class);
    QX11PixmapData *pixmapData = static_cast<QX11PixmapData*>(pmd);
    if (pixmapData->gl_surface) {
        EGLBoolean success;
        success = eglDestroySurface(QEglContext::defaultDisplay(0), (EGLSurface)pixmapData->gl_surface);
        if (success == EGL_FALSE) {
            qWarning() << "destroyGlSurfaceForPixmap() - Error deleting surface: "
                       << QEglContext::errorString(eglGetError());
        }
        pixmapData->gl_surface = 0;
    }
}

void QGLContextPrivate::unbindPixmapFromTexture(QPixmapData* pmd)
{
    Q_ASSERT(pmd->classId() == QPixmapData::X11Class);
    QX11PixmapData *pixmapData = static_cast<QX11PixmapData*>(pmd);
    if (pixmapData->gl_surface) {
        EGLBoolean success;
        success = eglReleaseTexImage(QEglContext::defaultDisplay(0),
                                     (EGLSurface)pixmapData->gl_surface,
                                     EGL_BACK_BUFFER);
        if (success == EGL_FALSE) {
            qWarning() << "unbindPixmapFromTexture() - Unable to release bound texture: "
                       << QEglContext::errorString(eglGetError());
        }
    }
}

QT_END_NAMESPACE