/****************************************************************************
**
** Copyright (C) 2014 BlackBerry Ltd.
** Copyright (C) 2015 The Qt Company Ltd.
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****************************************************************************/

#include "qquickopenglinfo_p.h"
#include "qopenglcontext.h"
#include "qquickwindow.h"
#include "qquickitem.h"

QT_BEGIN_NAMESPACE

/*!
    \qmltype OpenGLInfo
    \instantiates QQuickOpenGLInfo
    \inqmlmodule QtQuick
    \ingroup qtquick-effects
    \since 5.4
    \brief Provides information about the used OpenGL version

    The OpenGLInfo attached type provides information about the OpenGL
    version being used to render the surface of the attachee item.

    If the attachee item is not currently associated with any graphical
    surface, the properties are set to the values of the default surface
    format. When it becomes associated with a surface, all properties
    will update.

    \sa ShaderEffect
 */
QQuickOpenGLInfo::QQuickOpenGLInfo(QQuickItem *item)
    : QObject(item)
    , m_window(0)
    , m_majorVersion(2)
    , m_minorVersion(0)
    , m_profile(NoProfile)
    , m_renderableType(Unspecified)
{
    connect(item, SIGNAL(windowChanged(QQuickWindow*)), this, SLOT(setWindow(QQuickWindow*)));
    setWindow(item->window());
}

/*!
    \qmlproperty int QtQuick::OpenGLInfo::majorVersion

    This property holds the major OpenGL version.

    The default version is \c 2.0.

    \sa minorVersion, profile
 */
int QQuickOpenGLInfo::majorVersion() const
{
    return m_majorVersion;
}

/*!
    \qmlproperty int QtQuick::OpenGLInfo::minorVersion

    This property holds the minor OpenGL version.

    The default version is \c 2.0.

    \sa majorVersion, profile
 */
int QQuickOpenGLInfo::minorVersion() const
{
    return m_minorVersion;
}

/*!
    \qmlproperty enumeration QtQuick::OpenGLInfo::profile

    This property holds the configured OpenGL context profile.

    The possible values are:
    \list
    \li OpenGLInfo.NoProfile (default) - OpenGL version is lower than 3.2.
    \li OpenGLInfo.CoreProfile - Functionality deprecated in OpenGL version 3.0 is not available.
    \li OpenGLInfo.CompatibilityProfile - Functionality from earlier OpenGL versions is available.
    \endlist

    Reusable QML components will typically use this property in bindings in order to
    choose between core and non core profile compatible shader sources.

    \sa majorVersion, minorVersion
 */
QQuickOpenGLInfo::ContextProfile QQuickOpenGLInfo::profile() const
{
    return m_profile;
}

/*!
    \qmlproperty enumeration QtQuick::OpenGLInfo::renderableType

    This property holds the renderable type.

    The possible values are:
    \list
    \li OpenGLInfo.Unspecified (default) - Unspecified rendering method
    \li OpenGLInfo.OpenGL - Desktop OpenGL rendering
    \li OpenGLInfo.OpenGLES - OpenGL ES rendering
    \endlist
 */
QQuickOpenGLInfo::RenderableType QQuickOpenGLInfo::renderableType() const
{
    return m_renderableType;
}

QQuickOpenGLInfo *QQuickOpenGLInfo::qmlAttachedProperties(QObject *object)
{
    if (QQuickItem *item = qobject_cast<QQuickItem *>(object))
        return new QQuickOpenGLInfo(item);
    return 0;
}

void QQuickOpenGLInfo::updateFormat()
{
    QOpenGLContext *context = 0;
    if (m_window)
        context = m_window->openglContext();
    QSurfaceFormat format = context ? context->format() : QSurfaceFormat::defaultFormat();

    if (m_majorVersion != format.majorVersion()) {
        m_majorVersion = format.majorVersion();
        emit majorVersionChanged();
    }

    if (m_minorVersion != format.minorVersion()) {
        m_minorVersion = format.minorVersion();
        emit minorVersionChanged();
    }

    ContextProfile profile = static_cast<ContextProfile>(format.profile());
    if (m_profile != profile) {
        m_profile = profile;
        emit profileChanged();
    }

    RenderableType renderableType = static_cast<RenderableType>(format.renderableType());
    if (m_renderableType != renderableType) {
        m_renderableType = renderableType;
        emit renderableTypeChanged();
    }
}

void QQuickOpenGLInfo::setWindow(QQuickWindow *window)
{
    if (m_window != window) {
        if (m_window) {
            disconnect(m_window, SIGNAL(sceneGraphInitialized()), this, SLOT(updateFormat()));
            disconnect(m_window, SIGNAL(sceneGraphInvalidated()), this, SLOT(updateFormat()));
        }
        if (window) {
            connect(window, SIGNAL(sceneGraphInitialized()), this, SLOT(updateFormat()));
            connect(window, SIGNAL(sceneGraphInvalidated()), this, SLOT(updateFormat()));
        }
        m_window = window;
    }
    updateFormat();
}

QT_END_NAMESPACE