/****************************************************************************
**
** Copyright (C) 2014 Digia Plc
** All rights reserved.
** For any questions to Digia, please use contact form at http://qt.digia.com
**
** This file is part of the QtDataVisualization module.
**
** Licensees holding valid Qt Enterprise licenses may use this file in
** accordance with the Qt Enterprise License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia.
**
** If you have questions regarding the use of this file, please use
** contact form at http://qt.digia.com
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#include "qabstract3dgraph.h"
#include "qabstract3dgraph_p.h"
#include "abstract3dcontroller_p.h"
#include "qabstract3dinputhandler_p.h"
#include "q3dscene_p.h"
#include "qutils.h"

#include <QGuiApplication>
#include <QOpenGLContext>
#include <QOpenGLPaintDevice>
#include <QPainter>


QT_BEGIN_NAMESPACE_DATAVISUALIZATION

/*!
 * \class QAbstract3DGraph
 * \inmodule QtDataVisualization
 * \brief The QAbstract3DGraph class provides a window and render loop for graphs.
 * \since Qt Data Visualization 1.0
 *
 * This class subclasses a QWindow and provides render loop for graphs inheriting it.
 *
 * You should not need to use this class directly, but one of its subclasses instead.
 *
 * Anti-aliasing is turned on by default on C++, except in OpenGL ES2
 * environments, where anti-aliasing is not supported by Qt Data Visualization.
 * To specify non-default anti-aliasing for a graph, give a custom surface format as
 * a constructor parameter. You can use the convenience function \c QtDataVisualization::qDefaultSurfaceFormat()
 * to create the surface format object.
 *
 * \note QAbstract3DGraph sets window flag \c Qt::FramelessWindowHint on by default. If you want to display
 * graph windows as standalone windows with regular window frame, clear this flag after constructing
 * the graph. For example:
 *
 * \code
 *  Q3DBars *graphWindow = new Q3DBars;
 *  graphWindow->setFlags(graphWindow->flags() ^ Qt::FramelessWindowHint);
 * \endcode
 *
 * \sa Q3DBars, Q3DScatter, Q3DSurface, {Qt Data Visualization C++ Classes}
 */

/*!
    \enum QAbstract3DGraph::SelectionFlag

    Item selection modes. Values of this enumeration can be combined with OR operator.

    \value SelectionNone
           Selection mode disabled.
    \value SelectionItem
           Selection highlights a single item.
    \value SelectionRow
           Selection highlights a single row.
    \value SelectionItemAndRow
           Combination flag for highlighting both item and row with different colors.
    \value SelectionColumn
           Selection highlights a single column.
    \value SelectionItemAndColumn
           Combination flag for highlighting both item and column with different colors.
    \value SelectionRowAndColumn
           Combination flag for highlighting both row and column.
    \value SelectionItemRowAndColumn
           Combination flag for highlighting item, row, and column.
    \value SelectionSlice
           Setting this mode flag indicates that the graph should take care of the slice view handling
           automatically. If you wish to control the slice view yourself via Q3DScene, do not set this
           flag. When setting this mode flag, either \c SelectionRow or \c SelectionColumn must also
           be set, but not both. Slicing is supported by Q3DBars and Q3DSurface only.
           When this flag is set, slice mode is entered in the following situations:
           \list
           \li When selection is changed explicitly via series API to a visible item
           \li When selection is changed by clicking on the graph
           \li When the selection mode changes and the selected item is visible
           \endlist
    \value SelectionMultiSeries
           Setting this mode means that items for all series at same position are highlighted, instead
           of just the selected item. The actual selection in the other series doesn't change.
           Multi-series selection is not supported for Q3DScatter.
*/

/*!
    \enum QAbstract3DGraph::ShadowQuality

    Quality of shadows.

    \value ShadowQualityNone
           Shadows are disabled.
    \value ShadowQualityLow
           Shadows are rendered in low quality.
    \value ShadowQualityMedium
           Shadows are rendered in medium quality.
    \value ShadowQualityHigh
           Shadows are rendered in high quality.
    \value ShadowQualitySoftLow
           Shadows are rendered in low quality with softened edges.
    \value ShadowQualitySoftMedium
           Shadows are rendered in medium quality with softened edges.
    \value ShadowQualitySoftHigh
           Shadows are rendered in high quality with softened edges.
*/

/*!
 * \internal
 */
QAbstract3DGraph::QAbstract3DGraph(QAbstract3DGraphPrivate *d, const QSurfaceFormat *format,
                                   QWindow *parent)
    : QWindow(parent),
      d_ptr(d)
{
    qRegisterMetaType<QAbstract3DGraph::ShadowQuality>("QAbstract3DGraph::ShadowQuality");

    // Default to frameless window, as typically graphs are not toplevel
    setFlags(flags() | Qt::FramelessWindowHint);

    QSurfaceFormat surfaceFormat;
    if (format) {
        surfaceFormat = *format;
        // Make sure renderable type is correct
#if !defined(QT_OPENGL_ES_2)
        surfaceFormat.setRenderableType(QSurfaceFormat::OpenGL);
#else
        surfaceFormat.setRenderableType(QSurfaceFormat::OpenGLES);
#endif
    } else {
        surfaceFormat = qDefaultSurfaceFormat();
    }

    d_ptr->m_context = new QOpenGLContext(this);
    setSurfaceType(QWindow::OpenGLSurface);
    setFormat(surfaceFormat);

    create();

    d_ptr->m_context->setFormat(requestedFormat());
    d_ptr->m_context->create();
    d_ptr->m_context->makeCurrent(this);

    initializeOpenGLFunctions();

    const GLubyte *shaderVersion = glGetString(GL_SHADING_LANGUAGE_VERSION);
#ifndef QT_NO_DEBUG
    const GLubyte *openGLVersion = glGetString(GL_VERSION);
    qDebug() << "OpenGL version:" << (const char *)openGLVersion;
    qDebug() << "GLSL version:" << (const char *)shaderVersion;
#endif

#if !defined(QT_OPENGL_ES_2)
    // If we have real OpenGL, GLSL version must be 1.2 or over. Quit if not.
    QStringList splitversionstr = QString::fromLatin1((const char *)shaderVersion).split(QChar::fromLatin1(' '));
    if (splitversionstr[0].toFloat() < 1.2)
        qFatal("GLSL version must be 1.20 or higher. Try installing latest display drivers.");
#else
    Q_UNUSED(shaderVersion)
#endif

    d_ptr->renderLater();
}

/*!
 * Destroys QAbstract3DGraph.
 */
QAbstract3DGraph::~QAbstract3DGraph()
{
}

/*!
 * Adds the given \a inputHandler to the graph. The input handlers added via addInputHandler
 * are not taken in to use directly. Only the ownership of the \a inputHandler is given to the graph.
 * The \a inputHandler must not be null or already added to another graph.
 *
 * \sa releaseInputHandler(), setActiveInputHandler()
 */
void QAbstract3DGraph::addInputHandler(QAbstract3DInputHandler *inputHandler)
{
    d_ptr->m_visualController->addInputHandler(inputHandler);
}

/*!
 * Releases the ownership of the \a inputHandler back to the caller, if it was added to this graph.
 * If the released \a inputHandler is in use there will be no input handler active after this call.
 *
 * If the default input handler is released and added back later, it behaves as any other input handler would.
 *
 * \sa addInputHandler(), setActiveInputHandler()
 */
void QAbstract3DGraph::releaseInputHandler(QAbstract3DInputHandler *inputHandler)
{
    d_ptr->m_visualController->releaseInputHandler(inputHandler);
}

/*!
 * \property QAbstract3DGraph::activeInputHandler
 *
 * The active \a inputHandler used in the graph. Implicitly calls addInputHandler() to transfer
 * ownership of the \a inputHandler to this graph.
 *
 * If the \a inputHandler is null, no input handler will be active after this call.
 *
 * \sa addInputHandler(), releaseInputHandler()
 */
void QAbstract3DGraph::setActiveInputHandler(QAbstract3DInputHandler *inputHandler)
{
    d_ptr->m_visualController->setActiveInputHandler(inputHandler);
}

QAbstract3DInputHandler *QAbstract3DGraph::activeInputHandler()
{
    return d_ptr->m_visualController->activeInputHandler();
}

/*!
 * \return list of all added input handlers.
 *
 * \sa addInputHandler()
 */
QList<QAbstract3DInputHandler *> QAbstract3DGraph::inputHandlers() const
{
    return d_ptr->m_visualController->inputHandlers();
}

/*!
 * Adds the given \a theme to the graph. The themes added via addTheme are not taken in to use
 * directly. Only the ownership of the a\ theme is given to the graph.
 * The \a theme must not be null or already added to another graph.
 *
 * \sa releaseTheme(), setActiveTheme()
 */
void QAbstract3DGraph::addTheme(Q3DTheme *theme)
{
    d_ptr->m_visualController->addTheme(theme);
}

/*!
 * Releases the ownership of the \a theme back to the caller, if it was added to this graph.
 * If the released \a theme is in use, a new default theme will be created and set active.
 *
 * If the default theme is released and added back later, it behaves as any other theme would.
 *
 * \sa addTheme(), setActiveTheme()
 */
void QAbstract3DGraph::releaseTheme(Q3DTheme *theme)
{
    d_ptr->m_visualController->releaseTheme(theme);
}

/*!
 * \property QAbstract3DGraph::activeTheme
 *
 * The active \a theme to be used for the graph. Implicitly calls addTheme() to transfer ownership
 * of the \a theme to this graph.
 * If the \a theme is null, a temporary default theme is created. This temporary theme is destroyed
 * if any theme is explicitly set later.
 * Properties of the \a theme can be modified even after setting it, and the modifications take
 * effect immediately.
 */
void QAbstract3DGraph::setActiveTheme(Q3DTheme *theme)
{
    d_ptr->m_visualController->setActiveTheme(theme);
}


Q3DTheme *QAbstract3DGraph::activeTheme() const
{
    return d_ptr->m_visualController->activeTheme();
}

/*!
 * \return list of all added themes.
 *
 * \sa addTheme()
 */
QList<Q3DTheme *> QAbstract3DGraph::themes() const
{
    return d_ptr->m_visualController->themes();
}

/*!
 * \property QAbstract3DGraph::selectionMode
 *
 * Sets selection \a mode to a combination of SelectionFlags. It is preset to
 * \c SelectionItem by default.
 * Different graph types support different selection modes. See SelectionFlags
 * documentation for details.
 */
void QAbstract3DGraph::setSelectionMode(SelectionFlags mode)
{
    d_ptr->m_visualController->setSelectionMode(mode);
}

QAbstract3DGraph::SelectionFlags QAbstract3DGraph::selectionMode() const
{
    return d_ptr->m_visualController->selectionMode();
}

/*!
 * \property QAbstract3DGraph::shadowQuality
 *
 * Sets shadow \a quality to one of ShadowQuality. It is preset to
 * \c ShadowQualityMedium by default.
 *
 * \note If setting ShadowQuality of a certain level fails, a level is lowered
 * until it is successful and shadowQualityChanged signal is emitted for each time the change is
 * done.
 */
void QAbstract3DGraph::setShadowQuality(ShadowQuality quality)
{
    d_ptr->m_visualController->setShadowQuality(quality);
}

QAbstract3DGraph::ShadowQuality QAbstract3DGraph::shadowQuality() const
{
    return d_ptr->m_visualController->shadowQuality();
}

/*!
 * \property QAbstract3DGraph::scene
 *
 * This property contains the read only Q3DScene that can be used to access for example a camera object.
 */
Q3DScene *QAbstract3DGraph::scene() const
{
    return d_ptr->m_visualController->scene();
}

/*!
 * Clears selection from all attached series.
 */
void QAbstract3DGraph::clearSelection()
{
    d_ptr->m_visualController->clearSelection();
}

/*!
 * \internal
 */
bool QAbstract3DGraph::event(QEvent *event)
{
    switch (event->type()) {
    case QEvent::UpdateRequest:
        d_ptr->renderNow();
        return true;
    case QEvent::TouchBegin:
    case QEvent::TouchCancel:
    case QEvent::TouchUpdate:
    case QEvent::TouchEnd:
        d_ptr->m_visualController->touchEvent(static_cast<QTouchEvent *>(event));
        return true;
    default:
        return QWindow::event(event);
    }
}

/*!
 * \internal
 */
void QAbstract3DGraph::resizeEvent(QResizeEvent *event)
{
    Q_UNUSED(event);

    Q3DScene *scene = d_ptr->m_visualController->scene();
    scene->d_ptr->setWindowSize(QSize(width(), height()));
    scene->d_ptr->setViewport(QRect(0, 0, width(), height()));
}

/*!
 * \internal
 */
void QAbstract3DGraph::exposeEvent(QExposeEvent *event)
{
    Q_UNUSED(event);

    if (isExposed())
        d_ptr->renderNow();
}

/*!
 * \internal
 */
void QAbstract3DGraph::mouseDoubleClickEvent(QMouseEvent *event)
{
    d_ptr->m_visualController->mouseDoubleClickEvent(event);
}

/*!
 * \internal
 */
void QAbstract3DGraph::touchEvent(QTouchEvent *event)
{
    d_ptr->m_visualController->touchEvent(event);
}

/*!
 * \internal
 */
void QAbstract3DGraph::mousePressEvent(QMouseEvent *event)
{
    d_ptr->m_visualController->mousePressEvent(event, event->pos());
}

/*!
 * \internal
 */
void QAbstract3DGraph::mouseReleaseEvent(QMouseEvent *event)
{
    d_ptr->m_visualController->mouseReleaseEvent(event, event->pos());
}

/*!
 * \internal
 */
void QAbstract3DGraph::mouseMoveEvent(QMouseEvent *event)
{
    d_ptr->m_visualController->mouseMoveEvent(event, event->pos());
}

/*!
 * \internal
 */
void QAbstract3DGraph::wheelEvent(QWheelEvent *event)
{
    d_ptr->m_visualController->wheelEvent(event);
}

QAbstract3DGraphPrivate::QAbstract3DGraphPrivate(QAbstract3DGraph *q)
    : QObject(0),
      q_ptr(q),
      m_updatePending(false),
      m_visualController(0),
      m_devicePixelRatio(1.f)
{
}

QAbstract3DGraphPrivate::~QAbstract3DGraphPrivate()
{
    delete m_visualController;
}

void QAbstract3DGraphPrivate::setVisualController(Abstract3DController *controller)
{
    m_visualController = controller;

    QObject::connect(m_visualController, &Abstract3DController::activeInputHandlerChanged, q_ptr,
                     &QAbstract3DGraph::activeInputHandlerChanged);
    QObject::connect(m_visualController, &Abstract3DController::activeThemeChanged, q_ptr,
                     &QAbstract3DGraph::activeThemeChanged);
    QObject::connect(m_visualController, &Abstract3DController::selectionModeChanged, q_ptr,
                     &QAbstract3DGraph::selectionModeChanged);
    QObject::connect(m_visualController, &Abstract3DController::shadowQualityChanged, q_ptr,
                     &QAbstract3DGraph::shadowQualityChanged);
    QObject::connect(m_visualController, &Abstract3DController::needRender, this,
                     &QAbstract3DGraphPrivate::renderLater);

    QObject::connect(m_visualController, &Abstract3DController::axisXChanged, this,
                     &QAbstract3DGraphPrivate::handleAxisXChanged);
    QObject::connect(m_visualController, &Abstract3DController::axisYChanged, this,
                     &QAbstract3DGraphPrivate::handleAxisYChanged);
    QObject::connect(m_visualController, &Abstract3DController::axisZChanged, this,
                     &QAbstract3DGraphPrivate::handleAxisZChanged);
}

void QAbstract3DGraphPrivate::handleDevicePixelRatioChange()
{
    if (q_ptr->devicePixelRatio() == m_devicePixelRatio || !m_visualController)
        return;

    m_devicePixelRatio = q_ptr->devicePixelRatio();
    m_visualController->scene()->setDevicePixelRatio(m_devicePixelRatio);
}

void QAbstract3DGraphPrivate::render()
{
    handleDevicePixelRatioChange();
    m_visualController->synchDataToRenderer();
    m_visualController->render();
}

void QAbstract3DGraphPrivate::renderLater()
{
    if (!m_updatePending) {
        m_updatePending = true;
        QCoreApplication::postEvent(q_ptr, new QEvent(QEvent::UpdateRequest));
    }
}

void QAbstract3DGraphPrivate::renderNow()
{
    if (!q_ptr->isExposed())
        return;

    m_updatePending = false;

    m_context->makeCurrent(q_ptr);

    render();

    m_context->swapBuffers(q_ptr);
}

QT_END_NAMESPACE_DATAVISUALIZATION