/*
 * Copyright (C) 2001-2015 Klaralvdalens Datakonsult AB.  All rights reserved.
 *
 * This file is part of the KD Chart library.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

#include "KChartChart.h"
#include "KChartChart_p.h"

#include <QList>
#include <QtDebug>
#include <QGridLayout>
#include <QLabel>
#include <QHash>
#include <QToolTip>
#include <QPainter>
#include <QPaintEvent>
#include <QLayoutItem>
#include <QPushButton>
#include <QApplication>
#include <QEvent>

#include "KChartCartesianCoordinatePlane.h"
#include "KChartAbstractCartesianDiagram.h"
#include "KChartHeaderFooter.h"
#include "KChartEnums.h"
#include "KChartLegend.h"
#include "KChartLayoutItems.h"
#include <KChartTextAttributes.h>
#include <KChartMarkerAttributes.h>
#include "KChartPainterSaver_p.h"
#include "KChartPrintingParameters.h"

#include <algorithm>

#if defined KDAB_EVAL
#include "../evaldialog/evaldialog.h"
#endif

#if 0
// dumpLayoutTree dumps a QLayout tree in a hopefully easy to read format to stderr - feel free to
// use, improve and extend; it is very useful for looking at any layout problem.

#include <typeinfo>

// this is this different from both QRect::isEmpty() and QRect::isNull() for "wrong" QRects,
// i.e. those where topLeft() is actually below and / or right of bottomRight().
static bool isZeroArea(const QRect &r)
{
    return !r.width() || !r.height();
}

static QString lineProlog(int nestingDepth, int lineno)
{
    QString numbering(QString::number(lineno).rightJustified(5).append(QChar::fromAscii(':')));
    QString indent(nestingDepth * 4, QLatin1Char(' '));
    return numbering + indent;
}

static void dumpLayoutTreeRecurse(QLayout *l, int *counter, int depth)
{
    const QLatin1String colorOn(isZeroArea(l->geometry()) ? "\033[0m" : "\033[32m");
    const QLatin1String colorOff("\033[0m");

    QString prolog = lineProlog(depth, *counter);
    (*counter)++;

    qDebug() << colorOn + prolog << l->metaObject()->className() << l->geometry()
             << "hint" << l->sizeHint()
             << l->hasHeightForWidth() << "min" << l->minimumSize()
             << "max" << l->maximumSize()
             << l->expandingDirections() << l->alignment()
             << colorOff;
    for (int i = 0; i < l->count(); i++) {
        QLayoutItem *child = l->itemAt(i);
        if (QLayout *childL = child->layout()) {
            dumpLayoutTreeRecurse(childL, counter, depth + 1);
        } else {
            // The isZeroArea check culls usually largely useless output - you might want to remove it in
            // some debugging situations. Add a boolean parameter to this and dumpLayoutTree() if you do.
            if (!isZeroArea(child->geometry())) {
                prolog = lineProlog(depth + 1, *counter);
                (*counter)++;
                qDebug() << colorOn + prolog << typeid(*child).name() << child->geometry()
                         << "hint" << child->sizeHint()
                         << child->hasHeightForWidth() << "min" << child->minimumSize()
                         << "max" << child->maximumSize()
                         << child->expandingDirections() << child->alignment()
                         << colorOff;
            }
        }
    }
}

static void dumpLayoutTree(QLayout *l)
{
    int counter = 0;
    dumpLayoutTreeRecurse(l, &counter, 0);
}
#endif

static const Qt::Alignment s_gridAlignments[ 3 ][ 3 ] = { // [ row ][ column ]
    { Qt::AlignTop | Qt::AlignLeft,     Qt::AlignTop | Qt::AlignHCenter,     Qt::AlignTop | Qt::AlignRight },
    { Qt::AlignVCenter | Qt::AlignLeft, Qt::AlignVCenter | Qt::AlignHCenter, Qt::AlignVCenter | Qt::AlignRight },
    { Qt::AlignBottom | Qt::AlignLeft,  Qt::AlignBottom | Qt::AlignHCenter,  Qt::AlignBottom | Qt::AlignRight }
};

static void getRowAndColumnForPosition(KChartEnums::PositionValue pos, int* row, int* column)
{
    switch ( pos ) {
    case KChartEnums::PositionNorthWest:  *row = 0;  *column = 0;
        break;
    case KChartEnums::PositionNorth:      *row = 0;  *column = 1;
        break;
    case KChartEnums::PositionNorthEast:  *row = 0;  *column = 2;
        break;
    case KChartEnums::PositionEast:       *row = 1;  *column = 2;
        break;
    case KChartEnums::PositionSouthEast:  *row = 2;  *column = 2;
        break;
    case KChartEnums::PositionSouth:      *row = 2;  *column = 1;
        break;
    case KChartEnums::PositionSouthWest:  *row = 2;  *column = 0;
        break;
    case KChartEnums::PositionWest:       *row = 1;  *column = 0;
        break;
    case KChartEnums::PositionCenter:     *row = 1;  *column = 1;
        break;
    default:                               *row = -1; *column = -1;
        break;
    }
}

using namespace KChart;

// Layout widgets even if they are not visible (that's why isEmpty() is overridden) - at least that
// was the original reason...
class MyWidgetItem : public QWidgetItem
{
public:
    explicit MyWidgetItem(QWidget *w, Qt::Alignment alignment = Qt::Alignment())
        : QWidgetItem( w )
    {
        setAlignment( alignment );
    }

    // All of the methods are reimplemented from QWidgetItem, and work around some oddity in QLayout and / or
    // KD Chart - I forgot the details between writing this code as an experiment and committing it, very
    // sorry about that!
    // Feel free to comment out any of them and then try the line-breaking feature in horizontal legends in
    // the Legends/Advanced example. It will not work well in various ways - won't get enough space and look
    // very broken, will inhibit resizing the window etc.

    QSize sizeHint() const override
    {
        QWidget* w = const_cast< MyWidgetItem * >( this )->widget();
        return w->sizeHint();
    }

    QSize minimumSize() const override
    {
        QWidget* w = const_cast< MyWidgetItem * >( this )->widget();
        return w->minimumSize();
    }

    QSize maximumSize() const override
    {
        // Not just passing on w->maximumSize() fixes that the size policy of Legend is disregarded, making
        // Legend take all available space, which makes both the Legend internal layout and the overall
        // layout of chart + legend look bad. QWidget::maximumSize() is not a virtual method, it's a
        // property, so "overriding" that one would be even uglier, and prevent user-set property
        // values from doing anything.
        QWidget* w = const_cast< MyWidgetItem * >( this )->widget();
        QSize ret = w->maximumSize();
        const QSize hint = w->sizeHint();
        const QSizePolicy::Policy hPolicy = w->sizePolicy().horizontalPolicy();
        if (hPolicy == QSizePolicy::Fixed || hPolicy == QSizePolicy::Maximum) {
            ret.rwidth() = hint.width();
        }
        const QSizePolicy::Policy vPolicy = w->sizePolicy().verticalPolicy();
        if (vPolicy == QSizePolicy::Fixed || vPolicy == QSizePolicy::Maximum) {
            ret.rheight() = hint.height();
        }
        return ret;
    }

    Qt::Orientations expandingDirections() const override
    {
        QWidget* w = const_cast< MyWidgetItem * >( this )->widget();
        if ( isEmpty() ) {
            return Qt::Orientations();
        }
        Qt::Orientations e = w->sizePolicy().expandingDirections();
        return e;
    }

    void setGeometry(const QRect &g) override
    {
        QWidget* w = const_cast< MyWidgetItem * >( this )->widget();
        w->setGeometry(g);
    }

    QRect geometry() const override
    {
        QWidget* w = const_cast< MyWidgetItem * >( this )->widget();
        return w->geometry();
    }

    bool hasHeightForWidth() const override
    {
        QWidget* w = const_cast< MyWidgetItem * >( this )->widget();
        bool ret = !isEmpty() &&
        qobject_cast< Legend* >( w )->hasHeightForWidth();
        return ret;
    }

    int heightForWidth( int width ) const override
    {
        QWidget* w = const_cast< MyWidgetItem * >( this )->widget();
        int ret = w->heightForWidth( width );
        return ret;
    }

    bool isEmpty() const override {
        QWidget* w = const_cast< MyWidgetItem * >( this )->widget();
        // legend->hide() should indeed hide the legend,
        // but a legend in a chart that hasn't been shown yet isn't hidden
        // (as can happen when using Chart::paint() without showing the chart)
        return w->isHidden() && w->testAttribute( Qt::WA_WState_ExplicitShowHide );
    }
};

// When "abusing" QLayouts to lay out items with different geometry from the backing QWidgets,
// some manual work is required to correctly update all the sublayouts.
// This is because all the convenient ways to deal with QLayouts assume QWidgets somewhere.
// What this does is somewhat similar to QLayout::activate(), but it never refers to the parent
// QWidget which has the wrong geometry.
static void invalidateLayoutTree( QLayoutItem *item )
{
    QLayout *layout = item->layout();
    if ( layout ) {
        const int count = layout->count();
        for ( int i = 0; i < count; i++ ) {
            invalidateLayoutTree( layout->itemAt( i ) );
        }
    }
    item->invalidate();
}

void Chart::Private::slotUnregisterDestroyedLegend( Legend *l )
{
    chart->takeLegend( l );
}

void Chart::Private::slotUnregisterDestroyedHeaderFooter( HeaderFooter* hf )
{
    chart->takeHeaderFooter( hf );
}

void Chart::Private::slotUnregisterDestroyedPlane( AbstractCoordinatePlane* plane )
{
    coordinatePlanes.removeAll( plane );
    Q_FOREACH ( AbstractCoordinatePlane* p, coordinatePlanes ) {
        if ( p->referenceCoordinatePlane() == plane) {
            p->setReferenceCoordinatePlane( nullptr );
        }
    }
    plane->layoutPlanes();
}

Chart::Private::Private( Chart* chart_ )
    : chart( chart_ )
    , useNewLayoutSystem( false )
    , layout(nullptr)
    , vLayout(nullptr)
    , planesLayout(nullptr)
    , headerLayout(nullptr)
    , footerLayout(nullptr)
    , dataAndLegendLayout(nullptr)
    , leftOuterSpacer(nullptr)
    , rightOuterSpacer(nullptr)
    , topOuterSpacer(nullptr)
    , bottomOuterSpacer(nullptr)
    , isFloatingLegendsLayoutDirty( true )
    , isPlanesLayoutDirty( true )
    , globalLeadingLeft(0)
    , globalLeadingRight(0)
    , globalLeadingTop(0)
    , globalLeadingBottom(0)
{
    for ( int row = 0; row < 3; ++row ) {
        for ( int column = 0; column < 3; ++column ) {
            for ( int i = 0; i < 2; i++ ) {
                innerHdFtLayouts[ i ][ row ][ column ] = nullptr;
            }
        }
    }
}

Chart::Private::~Private()
{
}

enum VisitorState{ Visited, Unknown };
struct ConnectedComponentsComparator{
    bool operator()( const LayoutGraphNode *lhs, const LayoutGraphNode *rhs ) const
    {
        return lhs->priority < rhs->priority;
    }
};

static QVector< LayoutGraphNode* > getPrioritySortedConnectedComponents( QVector< LayoutGraphNode* > &nodeList )
{
    QVector< LayoutGraphNode* >connectedComponents;
    QHash< LayoutGraphNode*, VisitorState > visitedComponents;
    Q_FOREACH ( LayoutGraphNode* node, nodeList )
        visitedComponents[ node ] = Unknown;
    for ( int i = 0; i < nodeList.size(); ++i )
    {
        LayoutGraphNode *curNode = nodeList[ i ];
        LayoutGraphNode *representativeNode = curNode;
        if ( visitedComponents[ curNode ] != Visited )
        {
            QStack< LayoutGraphNode* > stack;
            stack.push( curNode );
            while ( !stack.isEmpty() )
            {
                curNode = stack.pop();
                Q_ASSERT( visitedComponents[ curNode ] != Visited );
                visitedComponents[ curNode ] = Visited;
                if ( curNode->bottomSuccesor && visitedComponents[ curNode->bottomSuccesor ] != Visited )
                    stack.push( curNode->bottomSuccesor );
                if ( curNode->leftSuccesor && visitedComponents[ curNode->leftSuccesor ] != Visited )
                    stack.push( curNode->leftSuccesor );
                if ( curNode->sharedSuccesor && visitedComponents[ curNode->sharedSuccesor ] != Visited )
                    stack.push( curNode->sharedSuccesor );
                if ( curNode->priority < representativeNode->priority )
                    representativeNode = curNode;
            }
            connectedComponents.append( representativeNode );
        }
    }
    std::sort( connectedComponents.begin(), connectedComponents.end(), ConnectedComponentsComparator() );
    return connectedComponents;
}

struct PriorityComparator{
public:
    PriorityComparator( QHash< AbstractCoordinatePlane*, LayoutGraphNode* > mapping )
        : m_mapping( mapping )
    {}
    bool operator() ( AbstractCoordinatePlane *lhs, AbstractCoordinatePlane *rhs ) const
    {
        const LayoutGraphNode *lhsNode = m_mapping[ lhs ];
        Q_ASSERT( lhsNode );
        const LayoutGraphNode *rhsNode = m_mapping[ rhs ];
        Q_ASSERT( rhsNode );
        return lhsNode->priority < rhsNode->priority;
    }

    const QHash< AbstractCoordinatePlane*, LayoutGraphNode* > m_mapping;
};

void checkExistingAxes( LayoutGraphNode* node )
{
    if ( node && node->diagramPlane && node->diagramPlane->diagram() )
    {
        AbstractCartesianDiagram *diag = qobject_cast< AbstractCartesianDiagram* >( node->diagramPlane->diagram() );
        if ( diag )
        {
            Q_FOREACH( const CartesianAxis* axis, diag->axes() )
            {
                switch ( axis->position() )
                {
                case( CartesianAxis::Top ):
                    node->topAxesLayout = true;
                    break;
                case( CartesianAxis::Bottom ):
                    node->bottomAxesLayout = true;
                    break;
                case( CartesianAxis::Left ):
                    node->leftAxesLayout = true;
                    break;
                case( CartesianAxis::Right ):
                    node->rightAxesLayout = true;
                    break;
                }
            }
        }
    }
}

static void mergeNodeAxisInformation( LayoutGraphNode* lhs, LayoutGraphNode* rhs )
{
    lhs->topAxesLayout |= rhs->topAxesLayout;
    rhs->topAxesLayout = lhs->topAxesLayout;

    lhs->bottomAxesLayout |= rhs->bottomAxesLayout;
    rhs->bottomAxesLayout = lhs->bottomAxesLayout;

    lhs->leftAxesLayout |= rhs->leftAxesLayout;
    rhs->leftAxesLayout = lhs->leftAxesLayout;

    lhs->rightAxesLayout |= rhs->rightAxesLayout;
    rhs->rightAxesLayout = lhs->rightAxesLayout;
}

static CoordinatePlaneList findSharingAxisDiagrams( AbstractCoordinatePlane* plane,
                                                    const CoordinatePlaneList& list,
                                                    Chart::Private::AxisType type,
                                                    QVector< CartesianAxis* >* sharedAxes )
{
    if ( !plane || !plane->diagram() )
        return CoordinatePlaneList();
    Q_ASSERT( plane );
    Q_ASSERT( plane->diagram() );
    CoordinatePlaneList result;
    AbstractCartesianDiagram* diagram = qobject_cast< AbstractCartesianDiagram* >( plane->diagram() );
    if ( !diagram )
        return CoordinatePlaneList();

    QList< CartesianAxis* > axes;
    Q_FOREACH( CartesianAxis* axis, diagram->axes() ) {
        if ( ( type == Chart::Private::Ordinate &&
              ( axis->position() == CartesianAxis::Left || axis->position() == CartesianAxis::Right ) )
            ||
             ( type == Chart::Private::Abscissa &&
              ( axis->position() == CartesianAxis::Top || axis->position() == CartesianAxis::Bottom ) ) ) {
            axes.append( axis );
        }
    }
    Q_FOREACH( AbstractCoordinatePlane *curPlane, list )
    {
        AbstractCartesianDiagram* diagram =
                qobject_cast< AbstractCartesianDiagram* > ( curPlane->diagram() );
        if ( !diagram )
            continue;
        Q_FOREACH( CartesianAxis* curSearchedAxis, axes )
        {
            Q_FOREACH( CartesianAxis* curAxis, diagram->axes() )
            {
                if ( curSearchedAxis == curAxis )
                {
                    result.append( curPlane );
                    if ( !sharedAxes->contains( curSearchedAxis ) )
                        sharedAxes->append( curSearchedAxis );
                }
            }
        }
    }

    return result;
}

/*
  * this method determines the needed layout of the graph
  * taking care of the sharing problematic
  * its NOT allowed to have a diagram that shares
  * more than one axis in the same direction
  */
QVector< LayoutGraphNode* > Chart::Private::buildPlaneLayoutGraph()
{
    QHash< AbstractCoordinatePlane*, LayoutGraphNode* > planeNodeMapping;
    QVector< LayoutGraphNode* > allNodes;
    // create all nodes and a mapping between plane and nodes
    Q_FOREACH( AbstractCoordinatePlane* curPlane, coordinatePlanes )
    {
        if ( curPlane->diagram() )
        {
            allNodes.append( new LayoutGraphNode );
            allNodes[ allNodes.size() - 1 ]->diagramPlane = curPlane;
            allNodes[ allNodes.size() - 1 ]->priority = allNodes.size();
            checkExistingAxes( allNodes[ allNodes.size() - 1 ] );
            planeNodeMapping[ curPlane ] = allNodes[ allNodes.size() - 1 ];
        }
    }
    // build the graph connections
    Q_FOREACH( LayoutGraphNode* curNode, allNodes )
    {
        QVector< CartesianAxis* > sharedAxes;
        CoordinatePlaneList xSharedPlanes = findSharingAxisDiagrams( curNode->diagramPlane, coordinatePlanes, Abscissa, &sharedAxes );
        Q_ASSERT( sharedAxes.size() < 2 );
        // TODO duplicated code make a method out of it
        if ( sharedAxes.size() == 1 && xSharedPlanes.size() > 1 )
        {
            //xSharedPlanes.removeAll( sharedAxes.first()->diagram()->coordinatePlane() );
            //std::sort( xSharedPlanes.begin(), xSharedPlanes.end(), PriorityComparator( planeNodeMapping ) );
            for ( int i = 0; i < xSharedPlanes.size() - 1; ++i )
            {
                LayoutGraphNode *tmpNode = planeNodeMapping[ xSharedPlanes[ i ] ];
                Q_ASSERT( tmpNode );
                LayoutGraphNode *tmpNode2 = planeNodeMapping[ xSharedPlanes[ i + 1 ] ];
                Q_ASSERT( tmpNode2 );
                tmpNode->bottomSuccesor = tmpNode2;
            }
//            if ( sharedAxes.first()->diagram() &&  sharedAxes.first()->diagram()->coordinatePlane() )
//            {
//                LayoutGraphNode *lastNode = planeNodeMapping[ xSharedPlanes.last() ];
//                Q_ASSERT( lastNode );
//                Q_ASSERT( sharedAxes.first()->diagram()->coordinatePlane() );
//                LayoutGraphNode *ownerNode = planeNodeMapping[ sharedAxes.first()->diagram()->coordinatePlane() ];
//                Q_ASSERT( ownerNode );
//                lastNode->bottomSuccesor = ownerNode;
//            }
            //merge AxisInformation, needs a two pass run
            LayoutGraphNode axisInfoNode;
            for ( int count = 0; count < 2; ++count )
            {
                for ( int i = 0; i < xSharedPlanes.size(); ++i )
                {
                    mergeNodeAxisInformation( &axisInfoNode, planeNodeMapping[ xSharedPlanes[ i ] ] );
                }
            }
        }
        sharedAxes.clear();
        CoordinatePlaneList ySharedPlanes = findSharingAxisDiagrams( curNode->diagramPlane, coordinatePlanes, Ordinate, &sharedAxes );
        Q_ASSERT( sharedAxes.size() < 2 );
        if ( sharedAxes.size() == 1 && ySharedPlanes.size() > 1 )
        {
            //ySharedPlanes.removeAll( sharedAxes.first()->diagram()->coordinatePlane() );
            //std::sort( ySharedPlanes.begin(), ySharedPlanes.end(), PriorityComparator( planeNodeMapping ) );
            for ( int i = 0; i < ySharedPlanes.size() - 1; ++i )
            {
                LayoutGraphNode *tmpNode = planeNodeMapping[ ySharedPlanes[ i ] ];
                Q_ASSERT( tmpNode );
                LayoutGraphNode *tmpNode2 = planeNodeMapping[ ySharedPlanes[ i + 1 ] ];
                Q_ASSERT( tmpNode2 );
                tmpNode->leftSuccesor = tmpNode2;
            }
//            if ( sharedAxes.first()->diagram() &&  sharedAxes.first()->diagram()->coordinatePlane() )
//            {
//                LayoutGraphNode *lastNode = planeNodeMapping[ ySharedPlanes.last() ];
//                Q_ASSERT( lastNode );
//                Q_ASSERT( sharedAxes.first()->diagram()->coordinatePlane() );
//                LayoutGraphNode *ownerNode = planeNodeMapping[ sharedAxes.first()->diagram()->coordinatePlane() ];
//                Q_ASSERT( ownerNode );
//                lastNode->bottomSuccesor = ownerNode;
//            }
            //merge AxisInformation, needs a two pass run
            LayoutGraphNode axisInfoNode;
            for ( int count = 0; count < 2; ++count )
            {
                for ( int i = 0; i < ySharedPlanes.size(); ++i )
                {
                    mergeNodeAxisInformation( &axisInfoNode, planeNodeMapping[ ySharedPlanes[ i ] ] );
                }
            }
        }
        sharedAxes.clear();
        if ( curNode->diagramPlane->referenceCoordinatePlane() )
            curNode->sharedSuccesor = planeNodeMapping[ curNode->diagramPlane->referenceCoordinatePlane() ];
    }

    return allNodes;
}

QHash<AbstractCoordinatePlane*, PlaneInfo> Chart::Private::buildPlaneLayoutInfos()
{
    /* There are two ways in which planes can be caused to interact in
     * where they are put layouting wise: The first is the reference plane. If
     * such a reference plane is set, on a plane, it will use the same cell in the
     * layout as that one. In addition to this, planes can share an axis. In that case
     * they will be laid out in relation to each other as suggested by the position
     * of the axis. If, for example Plane1 and Plane2 share an axis at position Left,
     * that will result in the layout: Axis Plane1 Plane 2, vertically. If Plane1
     * also happens to be Plane2's referece plane, both planes are drawn over each
     * other. The reference plane concept allows two planes to share the same space
     * even if neither has any axis, and in case there are shared axis, it is used
     * to decided, whether the planes should be painted on top of each other or
     * laid out vertically or horizontally next to each other. */
    QHash<CartesianAxis*, AxisInfo> axisInfos;
    QHash<AbstractCoordinatePlane*, PlaneInfo> planeInfos;
    Q_FOREACH(AbstractCoordinatePlane* plane, coordinatePlanes ) {
        PlaneInfo p;
        // first check if we share space with another plane
        p.referencePlane = plane->referenceCoordinatePlane();
        planeInfos.insert( plane, p );

        Q_FOREACH( AbstractDiagram* abstractDiagram, plane->diagrams() ) {
            AbstractCartesianDiagram* diagram =
                    qobject_cast<AbstractCartesianDiagram*> ( abstractDiagram );
            if ( !diagram ) {
                continue;
            }

            Q_FOREACH( CartesianAxis* axis, diagram->axes() ) {
                if ( !axisInfos.contains( axis ) ) {
                    /* If this is the first time we see this axis, add it, with the
                     * current plane. The first plane added to the chart that has
                     * the axis associated with it thus "owns" it, and decides about
                     * layout. */
                    AxisInfo i;
                    i.plane = plane;
                    axisInfos.insert( axis, i );
                } else {
                    AxisInfo i = axisInfos[axis];
                    if ( i.plane == plane ) {
                        continue; // we don't want duplicates, only shared
                    }

                    /* The user expects diagrams to be added on top, and to the right
                     * so that horizontally we need to move the new diagram, vertically
                     * the reference one. */
                    PlaneInfo pi = planeInfos[plane];
                    // plane-to-plane linking overrides linking via axes
                    if ( !pi.referencePlane ) {
                        // we're not the first plane to see this axis, mark us as a slave
                        pi.referencePlane = i.plane;
                        if ( axis->position() == CartesianAxis::Left ||
                             axis->position() == CartesianAxis::Right ) {
                            pi.horizontalOffset += 1;
                        }
                        planeInfos[plane] = pi;

                        pi = planeInfos[i.plane];
                        if ( axis->position() == CartesianAxis::Top ||
                             axis->position() == CartesianAxis::Bottom )  {
                            pi.verticalOffset += 1;
                        }

                        planeInfos[i.plane] = pi;
                    }
                }
            }
        }
        // Create a new grid layout for each plane that has no reference.
        p = planeInfos[plane];
        if ( p.referencePlane == nullptr ) {
            p.gridLayout = new QGridLayout();
            p.gridLayout->setContentsMargins( 0, 0, 0, 0 );
            planeInfos[plane] = p;
        }
    }
    return planeInfos;
}

void Chart::Private::slotLayoutPlanes()
{
    /*TODO make sure this is really needed */
    const QBoxLayout::Direction oldPlanesDirection = planesLayout ? planesLayout->direction()
                                                                  : QBoxLayout::TopToBottom;
    if ( planesLayout && dataAndLegendLayout )
        dataAndLegendLayout->removeItem( planesLayout );

    const bool hadPlanesLayout = planesLayout != nullptr;
    int left, top, right, bottom;
    if ( hadPlanesLayout )
        planesLayout->getContentsMargins(&left, &top, &right, &bottom);

    Q_FOREACH( AbstractLayoutItem* plane, planeLayoutItems ) {
        plane->removeFromParentLayout();
    }
    //TODO they should get a correct parent, but for now it works
    Q_FOREACH( AbstractLayoutItem* plane, planeLayoutItems ) {
        if ( dynamic_cast< AutoSpacerLayoutItem* >( plane ) )
            delete plane;
    }

    planeLayoutItems.clear();
    delete planesLayout;
    //hint: The direction is configurable by the user now, as
    //      we are using a QBoxLayout rather than a QVBoxLayout.  (khz, 2007/04/25)
    planesLayout = new QBoxLayout( oldPlanesDirection );

    isPlanesLayoutDirty = true; // here we create the layouts; we need to "run" them before painting

    if ( useNewLayoutSystem )
    {
        gridPlaneLayout = new QGridLayout;
        planesLayout->addLayout( gridPlaneLayout );

        if (hadPlanesLayout)
            planesLayout->setContentsMargins(left, top, right, bottom);
        planesLayout->setObjectName( QString::fromLatin1( "planesLayout" ) );

        /* First go through all planes and all axes and figure out whether the planes
         * need to coordinate. If they do, they share a grid layout, if not, each
         * get their own. See buildPlaneLayoutInfos() for more details. */

        QVector< LayoutGraphNode* > vals = buildPlaneLayoutGraph();
        //qDebug() << Q_FUNC_INFO << "GraphNodes" << vals.size();
        QVector< LayoutGraphNode* > connectedComponents = getPrioritySortedConnectedComponents( vals );
        //qDebug() << Q_FUNC_INFO << "SubGraphs" << connectedComponents.size();
        int row = 0;
        int col = 0;
        QSet< CartesianAxis* > laidOutAxes;
        for ( int i = 0; i < connectedComponents.size(); ++i )
        {
            LayoutGraphNode *curComponent = connectedComponents[ i ];
            for ( LayoutGraphNode *curRowComponent = curComponent; curRowComponent; curRowComponent = curRowComponent->bottomSuccesor )
            {
                col = 0;
                for ( LayoutGraphNode *curColComponent = curRowComponent; curColComponent; curColComponent = curColComponent->leftSuccesor )
                {
                    Q_ASSERT( curColComponent->diagramPlane->diagrams().size() == 1 );
                    Q_FOREACH( AbstractDiagram* diagram, curColComponent->diagramPlane->diagrams() )
                    {
                        const int planeRowOffset = 1;//curColComponent->topAxesLayout ? 1 : 0;
                        const int planeColOffset = 1;//curColComponent->leftAxesLayout ? 1 : 0;
                        //qDebug() << Q_FUNC_INFO << row << col << planeRowOffset << planeColOffset;

                        //qDebug() << Q_FUNC_INFO << row + planeRowOffset << col + planeColOffset;
                        planeLayoutItems << curColComponent->diagramPlane;
                        AbstractCartesianDiagram *cartDiag = qobject_cast< AbstractCartesianDiagram* >( diagram );
                        if ( cartDiag )
                        {
                            gridPlaneLayout->addItem( curColComponent->diagramPlane, row + planeRowOffset, col + planeColOffset, 2, 2 );
                            curColComponent->diagramPlane->setParentLayout( gridPlaneLayout );
                            QHBoxLayout *leftLayout = nullptr;
                            QHBoxLayout *rightLayout = nullptr;
                            QVBoxLayout *topLayout = nullptr;
                            QVBoxLayout *bottomLayout = nullptr;
                            if ( curComponent->sharedSuccesor )
                            {
                                gridPlaneLayout->addItem( curColComponent->sharedSuccesor->diagramPlane, row + planeRowOffset, col + planeColOffset, 2, 2 );
                                curColComponent->sharedSuccesor->diagramPlane->setParentLayout( gridPlaneLayout );
                                planeLayoutItems << curColComponent->sharedSuccesor->diagramPlane;
                            }
                            Q_FOREACH( CartesianAxis* axis, cartDiag->axes() )
                            {
                                if ( axis->isAbscissa() )
                                {
                                    if ( curColComponent->bottomSuccesor )
                                        continue;
                                }
                                if ( laidOutAxes.contains( axis ) )
                                    continue;
        //                        if ( axis->diagram() != diagram )
        //                            continue;
                                switch ( axis->position() )
                                {
                                case( CartesianAxis::Top ):
                                    if ( !topLayout )
                                        topLayout = new QVBoxLayout;
                                    topLayout->addItem( axis );
                                    axis->setParentLayout( topLayout );
                                    break;
                                case( CartesianAxis::Bottom ):
                                    if ( !bottomLayout )
                                        bottomLayout = new QVBoxLayout;
                                    bottomLayout->addItem( axis );
                                    axis->setParentLayout( bottomLayout );
                                    break;
                                case( CartesianAxis::Left ):
                                    if ( !leftLayout )
                                        leftLayout = new QHBoxLayout;
                                    leftLayout->addItem( axis );
                                    axis->setParentLayout( leftLayout );
                                    break;
                                case( CartesianAxis::Right ):
                                    if ( !rightLayout )
                                    {
                                        rightLayout = new QHBoxLayout;
                                    }
                                    rightLayout->addItem( axis );
                                    axis->setParentLayout( rightLayout );
                                    break;
                                }
                                planeLayoutItems << axis;
                                laidOutAxes.insert( axis );
                            }
                            if ( leftLayout )
                                gridPlaneLayout->addLayout( leftLayout, row + planeRowOffset, col, 2, 1,
                                                            Qt::AlignRight | Qt::AlignVCenter );
                            if ( rightLayout )
                                gridPlaneLayout->addLayout( rightLayout, row, col + planeColOffset + 2, 2, 1,
                                                            Qt::AlignLeft | Qt::AlignVCenter );
                            if ( topLayout )
                                gridPlaneLayout->addLayout( topLayout, row, col + planeColOffset, 1, 2,
                                                            Qt::AlignBottom | Qt::AlignHCenter );
                            if ( bottomLayout )
                                gridPlaneLayout->addLayout( bottomLayout, row + planeRowOffset + 2,
                                                            col + planeColOffset, 1, 2, Qt::AlignTop | Qt::AlignHCenter );
                        }
                        else
                        {
                            gridPlaneLayout->addItem( curColComponent->diagramPlane, row, col, 4, 4 );
                            curColComponent->diagramPlane->setParentLayout( gridPlaneLayout );
                        }
                        col += planeColOffset + 2 + ( 1 );
                    }
                }
                int axisOffset = 2;//curRowComponent->topAxesLayout ? 1 : 0;
                //axisOffset += curRowComponent->bottomAxesLayout ? 1 : 0;
                const int rowOffset = axisOffset + 2;
                row += rowOffset;
            }

    //        if ( planesLayout->direction() == QBoxLayout::TopToBottom )
    //            ++row;
    //        else
    //            ++col;
        }

        qDeleteAll( vals );
        // re-add our grid(s) to the chart's layout
        if ( dataAndLegendLayout ) {
            dataAndLegendLayout->addLayout( planesLayout, 1, 1 );
            dataAndLegendLayout->setRowStretch( 1, 1000 );
            dataAndLegendLayout->setColumnStretch( 1, 1000 );
        }
        slotResizePlanes();
#ifdef NEW_LAYOUT_DEBUG
        for ( int i = 0; i < gridPlaneLayout->rowCount(); ++i )
        {
            for ( int j = 0; j < gridPlaneLayout->columnCount(); ++j )
            {
                if ( gridPlaneLayout->itemAtPosition( i, j ) )
                    qDebug() << Q_FUNC_INFO << "item at" << i << j << gridPlaneLayout->itemAtPosition( i, j )->geometry();
                else
                    qDebug() << Q_FUNC_INFO << "item at" << i << j << "no item present";
            }
        }
        //qDebug() << Q_FUNC_INFO << "Relayout ended";
#endif
    } else {
        if ( hadPlanesLayout ) {
            planesLayout->setContentsMargins( left, top, right, bottom );
        }

        planesLayout->setContentsMargins( 0, 0, 0, 0 );
        planesLayout->setSpacing( 0 );
        planesLayout->setObjectName( QString::fromLatin1( "planesLayout" ) );

        /* First go through all planes and all axes and figure out whether the planes
         * need to coordinate. If they do, they share a grid layout, if not, each
         * gets their own. See buildPlaneLayoutInfos() for more details. */
        QHash<AbstractCoordinatePlane*, PlaneInfo> planeInfos = buildPlaneLayoutInfos();
        QHash<AbstractAxis*, AxisInfo> axisInfos;
        Q_FOREACH( AbstractCoordinatePlane* plane, coordinatePlanes ) {
            Q_ASSERT( planeInfos.contains(plane) );
            PlaneInfo& pi = planeInfos[ plane ];
            const int column = pi.horizontalOffset;
            const int row = pi.verticalOffset;
            //qDebug() << "processing plane at column" << column << "and row" << row;
            QGridLayout *planeLayout = pi.gridLayout;

            if ( !planeLayout ) {
                PlaneInfo& refPi = pi;
                // if this plane is sharing an axis with another one, recursively check for the original plane and use
                // the grid of that as planeLayout.
                while ( !planeLayout && refPi.referencePlane ) {
                    refPi = planeInfos[refPi.referencePlane];
                    planeLayout = refPi.gridLayout;
                }
                Q_ASSERT_X( planeLayout,
                            "Chart::Private::slotLayoutPlanes()",
                            "Invalid reference plane. Please check that the reference plane has been added to the Chart." );
            } else {
                planesLayout->addLayout( planeLayout );
            }

            /* Put the plane in the center of the layout. If this is our own, that's
             * the middle of the layout, if we are sharing, it's a cell in the center
             * column of the shared grid. */
            planeLayoutItems << plane;
            plane->setParentLayout( planeLayout );
            planeLayout->addItem( plane, row, column, 1, 1 );
            //qDebug() << "Chart slotLayoutPlanes() calls planeLayout->addItem("<< row << column << ")";
            planeLayout->setRowStretch( row, 2 );
            planeLayout->setColumnStretch( column, 2 );
            Q_FOREACH( AbstractDiagram* abstractDiagram, plane->diagrams() )
            {
                AbstractCartesianDiagram* diagram =
                    qobject_cast< AbstractCartesianDiagram* >( abstractDiagram );
                if ( !diagram ) {
                    continue;  // FIXME what about polar ?
                }

                if ( pi.referencePlane != nullptr )
                {
                    pi.topAxesLayout = planeInfos[ pi.referencePlane ].topAxesLayout;
                    pi.bottomAxesLayout = planeInfos[ pi.referencePlane ].bottomAxesLayout;
                    pi.leftAxesLayout = planeInfos[ pi.referencePlane ].leftAxesLayout;
                    pi.rightAxesLayout = planeInfos[ pi.referencePlane ].rightAxesLayout;
                }

                // collect all axes of a kind into sublayouts
                if ( pi.topAxesLayout == nullptr )
                {
                    pi.topAxesLayout = new QVBoxLayout;
                    pi.topAxesLayout->setContentsMargins( 0, 0, 0, 0 );
                    pi.topAxesLayout->setObjectName( QString::fromLatin1( "topAxesLayout" ) );
                }
                if ( pi.bottomAxesLayout == nullptr )
                {
                    pi.bottomAxesLayout = new QVBoxLayout;
                    pi.bottomAxesLayout->setContentsMargins( 0, 0, 0, 0 );
                    pi.bottomAxesLayout->setObjectName( QString::fromLatin1( "bottomAxesLayout" ) );
                }
                if ( pi.leftAxesLayout == nullptr )
                {
                    pi.leftAxesLayout = new QHBoxLayout;
                    pi.leftAxesLayout->setContentsMargins( 0, 0, 0, 0 );
                    pi.leftAxesLayout->setObjectName( QString::fromLatin1( "leftAxesLayout" ) );
                }
                if ( pi.rightAxesLayout == nullptr )
                {
                    pi.rightAxesLayout = new QHBoxLayout;
                    pi.rightAxesLayout->setContentsMargins( 0, 0, 0, 0 );
                    pi.rightAxesLayout->setObjectName( QString::fromLatin1( "rightAxesLayout" ) );
                }

                if ( pi.referencePlane != nullptr )
                {
                    planeInfos[ pi.referencePlane ].topAxesLayout = pi.topAxesLayout;
                    planeInfos[ pi.referencePlane ].bottomAxesLayout = pi.bottomAxesLayout;
                    planeInfos[ pi.referencePlane ].leftAxesLayout = pi.leftAxesLayout;
                    planeInfos[ pi.referencePlane ].rightAxesLayout = pi.rightAxesLayout;
                }

                //pi.leftAxesLayout->setSizeConstraint( QLayout::SetFixedSize );
                Q_FOREACH( CartesianAxis* axis, diagram->axes() ) {
                    if ( axisInfos.contains( axis ) ) {
                        continue; // already laid out this one
                    }
                    Q_ASSERT ( axis );
                    axis->setCachedSizeDirty();
                    //qDebug() << "--------------- axis added to planeLayoutItems  -----------------";
                    planeLayoutItems << axis;

                    switch ( axis->position() ) {
                    case CartesianAxis::Top:
                        axis->setParentLayout( pi.topAxesLayout );
                        pi.topAxesLayout->addItem( axis );
                        break;
                    case CartesianAxis::Bottom:
                        axis->setParentLayout( pi.bottomAxesLayout );
                        pi.bottomAxesLayout->addItem( axis );
                        break;
                    case CartesianAxis::Left:
                        axis->setParentLayout( pi.leftAxesLayout );
                        pi.leftAxesLayout->addItem( axis );
                        break;
                    case CartesianAxis::Right:
                        axis->setParentLayout( pi.rightAxesLayout );
                        pi.rightAxesLayout->addItem( axis );
                        break;
                    default:
                        Q_ASSERT_X( false, "Chart::paintEvent", "unknown axis position" );
                        break;
                    };
                    axisInfos.insert( axis, AxisInfo() );
                }
                /* Put each stack of axes-layouts in the cells surrounding the
                 * associated plane. We are laying out in the oder the planes
                 * were added, and the first one gets to lay out shared axes.
                 * Private axes go here as well, of course. */

                if ( !pi.topAxesLayout->parent() ) {
                    planeLayout->addLayout( pi.topAxesLayout, row - 1, column );
                }
                if ( !pi.bottomAxesLayout->parent() ) {
                    planeLayout->addLayout( pi.bottomAxesLayout, row + 1, column );
                }
                if ( !pi.leftAxesLayout->parent() ) {
                    planeLayout->addLayout( pi.leftAxesLayout, row, column - 1 );
                }
                if ( !pi.rightAxesLayout->parent() ) {
                    planeLayout->addLayout( pi.rightAxesLayout,row, column + 1 );
                }
            }

            // use up to four auto-spacer items in the corners around the diagrams:
    #define ADD_AUTO_SPACER_IF_NEEDED( \
            spacerRow, spacerColumn, hLayoutIsAtTop, hLayout, vLayoutIsAtLeft, vLayout ) \
            { \
                if ( hLayout || vLayout ) { \
                    AutoSpacerLayoutItem * spacer \
                    = new AutoSpacerLayoutItem( hLayoutIsAtTop, hLayout, vLayoutIsAtLeft, vLayout ); \
                    planeLayout->addItem( spacer, spacerRow, spacerColumn, 1, 1 ); \
                    spacer->setParentLayout( planeLayout ); \
                    planeLayoutItems << spacer; \
                } \
            }

            if ( plane->isCornerSpacersEnabled() ) {
                ADD_AUTO_SPACER_IF_NEEDED( row - 1, column - 1, false, pi.leftAxesLayout,  false, pi.topAxesLayout )
                ADD_AUTO_SPACER_IF_NEEDED( row + 1, column - 1, true,  pi.leftAxesLayout,  false,  pi.bottomAxesLayout )
                ADD_AUTO_SPACER_IF_NEEDED( row - 1, column + 1, false, pi.rightAxesLayout, true, pi.topAxesLayout )
                ADD_AUTO_SPACER_IF_NEEDED( row + 1, column + 1, true,  pi.rightAxesLayout, true,  pi.bottomAxesLayout )
            }
        }
        // re-add our grid(s) to the chart's layout
        if ( dataAndLegendLayout ) {
            dataAndLegendLayout->addLayout( planesLayout, 1, 1 );
            dataAndLegendLayout->setRowStretch( 1, 1000 );
            dataAndLegendLayout->setColumnStretch( 1, 1000 );
        }

        slotResizePlanes();
    }
}

void Chart::Private::createLayouts()
{
    // The toplevel layout provides the left and right global margins
    layout = new QHBoxLayout( chart );
    layout->setContentsMargins( 0, 0, 0, 0 );
    layout->setObjectName( QString::fromLatin1( "Chart::Private::layout" ) );
    layout->addSpacing( globalLeadingLeft );
    leftOuterSpacer = layout->itemAt( layout->count() - 1 )->spacerItem();

    // The vLayout provides top and bottom global margins and lays
    // out headers, footers and the diagram area.
    vLayout = new QVBoxLayout();
    vLayout->setContentsMargins( 0, 0, 0, 0 );
    vLayout->setObjectName( QString::fromLatin1( "vLayout" ) );

    layout->addLayout( vLayout, 1000 );
    layout->addSpacing( globalLeadingRight );
    rightOuterSpacer = layout->itemAt( layout->count() - 1 )->spacerItem();

    // 1. the spacing above the header area
    vLayout->addSpacing( globalLeadingTop );
    topOuterSpacer = vLayout->itemAt( vLayout->count() - 1 )->spacerItem();
    // 2. the header area
    headerLayout = new QGridLayout();
    headerLayout->setContentsMargins( 0, 0, 0, 0 );
    vLayout->addLayout( headerLayout );
    // 3. the area containing coordinate planes, axes, and legends
    dataAndLegendLayout = new QGridLayout();
    dataAndLegendLayout->setContentsMargins( 0, 0, 0, 0 );
    dataAndLegendLayout->setObjectName( QString::fromLatin1( "dataAndLegendLayout" ) );
    vLayout->addLayout( dataAndLegendLayout, 1000 );
    // 4. the footer area
    footerLayout = new QGridLayout();
    footerLayout->setContentsMargins( 0, 0, 0, 0 );
    footerLayout->setObjectName( QString::fromLatin1( "footerLayout" ) );
    vLayout->addLayout( footerLayout );

    // 5. Prepare the header / footer layout cells:
    //    Each of the 9 header cells (the 9 footer cells)
    //    contain their own QVBoxLayout
    //    since there can be more than one header (footer) per cell.
    for ( int row = 0; row < 3; ++row ) {
        for ( int column = 0; column < 3; ++ column ) {
            const Qt::Alignment align = s_gridAlignments[ row ][ column ];
            for ( int headOrFoot = 0; headOrFoot < 2; headOrFoot++ ) {
                QVBoxLayout* innerLayout = new QVBoxLayout();
                innerLayout->setContentsMargins( 0, 0, 0, 0 );
                innerLayout->setAlignment( align );
                innerHdFtLayouts[ headOrFoot ][ row ][ column ] = innerLayout;

                QGridLayout* outerLayout = headOrFoot == 0 ? headerLayout : footerLayout;
                outerLayout->addLayout( innerLayout, row, column, align );
            }
        }
    }

    // 6. the spacing below the footer area
    vLayout->addSpacing( globalLeadingBottom );
    bottomOuterSpacer = vLayout->itemAt( vLayout->count() - 1 )->spacerItem();

    // the data+axes area
    dataAndLegendLayout->addLayout( planesLayout, 1, 1 );
    dataAndLegendLayout->setRowStretch( 1, 1 );
    dataAndLegendLayout->setColumnStretch( 1, 1 );
}

void Chart::Private::slotResizePlanes()
{
    if ( !dataAndLegendLayout ) {
        return;
    }
    if ( !overrideSize.isValid() ) {
        // activate() takes the size from the layout's parent QWidget, which is not updated when overrideSize
        // is set. So don't let the layout grab the wrong size in that case.
        // When overrideSize *is* set, we call layout->setGeometry() in paint( QPainter*, const QRect& ),
        // which also "activates" the layout in the sense that it distributes space internally.
        layout->activate();
    }
    // Adapt diagram drawing to the new size
    Q_FOREACH (AbstractCoordinatePlane* plane, coordinatePlanes ) {
        plane->layoutDiagrams();
    }
}

void Chart::Private::updateDirtyLayouts()
{
    if ( isPlanesLayoutDirty ) {
        Q_FOREACH ( AbstractCoordinatePlane* p, coordinatePlanes ) {
            p->setGridNeedsRecalculate();
            p->layoutPlanes();
            p->layoutDiagrams();
        }
    }
    if ( isPlanesLayoutDirty || isFloatingLegendsLayoutDirty ) {
        chart->reLayoutFloatingLegends();
    }
    isPlanesLayoutDirty = false;
    isFloatingLegendsLayoutDirty = false;
}

void Chart::Private::reapplyInternalLayouts()
{
    QRect geo = layout->geometry();

    invalidateLayoutTree( layout );
    layout->setGeometry( geo );
    slotResizePlanes();
}

void Chart::Private::paintAll( QPainter* painter )
{
    updateDirtyLayouts();

    QRect rect( QPoint( 0, 0 ), overrideSize.isValid() ? overrideSize : chart->size() );

    //qDebug() << this<<"::paintAll() uses layout size" << currentLayoutSize;

    // Paint the background (if any)
    AbstractAreaBase::paintBackgroundAttributes( *painter, rect, backgroundAttributes );
    // Paint the frame (if any)
    AbstractAreaBase::paintFrameAttributes( *painter, rect, frameAttributes );

    chart->reLayoutFloatingLegends();

    Q_FOREACH( AbstractLayoutItem* planeLayoutItem, planeLayoutItems ) {
        planeLayoutItem->paintAll( *painter );
    }
    Q_FOREACH( TextArea* textLayoutItem, textLayoutItems ) {
        textLayoutItem->paintAll( *painter );
    }
    Q_FOREACH( Legend *legend, legends ) {
        const bool hidden = legend->isHidden() && legend->testAttribute( Qt::WA_WState_ExplicitShowHide );
        if ( !hidden ) {
            //qDebug() << "painting legend at " << legend->geometry();
            legend->paintIntoRect( *painter, legend->geometry() );
        }
    }
}

// ******** Chart interface implementation ***********

#define d d_func()

Chart::Chart ( QWidget* parent )
    : QWidget ( parent )
    , _d( new Private( this ) )
{
#if defined KDAB_EVAL
    EvalDialog::checkEvalLicense( "KD Chart" );
#endif

    FrameAttributes frameAttrs;
// no frame per default...
//    frameAttrs.setVisible( true );
    frameAttrs.setPen( QPen( Qt::black ) );
    frameAttrs.setPadding( 1 );
    setFrameAttributes( frameAttrs );

    addCoordinatePlane( new CartesianCoordinatePlane ( this ) );

    d->createLayouts();
}

Chart::~Chart()
{
    delete d;
}

void Chart::setFrameAttributes( const FrameAttributes &a )
{
    d->frameAttributes = a;
}

FrameAttributes Chart::frameAttributes() const
{
    return d->frameAttributes;
}

void Chart::setBackgroundAttributes( const BackgroundAttributes &a )
{
    d->backgroundAttributes = a;
}

BackgroundAttributes Chart::backgroundAttributes() const
{
    return d->backgroundAttributes;
}

//TODO KChart 3.0; change QLayout into QBoxLayout::Direction
void Chart::setCoordinatePlaneLayout( QLayout * layout )
{
    if (layout == d->planesLayout)
        return;
    if (d->planesLayout) {
        // detach all QLayoutItem's the previous planesLayout has cause
        // otherwise deleting the planesLayout would delete them too.
        for(int i = d->planesLayout->count() - 1; i >= 0; --i) {
            d->planesLayout->takeAt(i);
        }
        delete d->planesLayout;
    }
    d->planesLayout = qobject_cast<QBoxLayout*>( layout );
    d->slotLayoutPlanes();
}

QLayout* Chart::coordinatePlaneLayout()
{
    return d->planesLayout;
}

AbstractCoordinatePlane* Chart::coordinatePlane()
{
    if ( d->coordinatePlanes.isEmpty() ) {
        qWarning() << "Chart::coordinatePlane: warning: no coordinate plane defined.";
        return nullptr;
    } else {
        return d->coordinatePlanes.first();
    }
}

CoordinatePlaneList Chart::coordinatePlanes()
{
    return d->coordinatePlanes;
}

void Chart::addCoordinatePlane( AbstractCoordinatePlane* plane )
{
    // Append
    insertCoordinatePlane( d->coordinatePlanes.count(), plane );
}

void Chart::insertCoordinatePlane( int index, AbstractCoordinatePlane* plane )
{
    if ( index < 0 || index > d->coordinatePlanes.count() ) {
        return;
    }

    connect( plane, SIGNAL(destroyedCoordinatePlane(AbstractCoordinatePlane*)),
             d,   SLOT(slotUnregisterDestroyedPlane(AbstractCoordinatePlane*)) );
    connect( plane, SIGNAL(needUpdate()),       this,   SLOT(update()) );
    connect( plane, SIGNAL(needRelayout()),     d,      SLOT(slotResizePlanes()) ) ;
    connect( plane, SIGNAL(needLayoutPlanes()), d,      SLOT(slotLayoutPlanes()) ) ;
    connect( plane, SIGNAL(propertiesChanged()),this, SIGNAL(propertiesChanged()) );
    d->coordinatePlanes.insert( index, plane );
    plane->setParent( this );
    d->slotLayoutPlanes();
}

void Chart::replaceCoordinatePlane( AbstractCoordinatePlane* plane,
                                    AbstractCoordinatePlane* oldPlane_ )
{
    if ( plane && oldPlane_ != plane ) {
        AbstractCoordinatePlane* oldPlane = oldPlane_;
        if ( d->coordinatePlanes.count() ) {
            if ( ! oldPlane ) {
                oldPlane = d->coordinatePlanes.first();
                if ( oldPlane == plane )
                    return;
            }
            takeCoordinatePlane( oldPlane );
        }
        delete oldPlane;
        addCoordinatePlane( plane );
    }
}

void Chart::takeCoordinatePlane( AbstractCoordinatePlane* plane )
{
    const int idx = d->coordinatePlanes.indexOf( plane );
    if ( idx != -1 ) {
        d->coordinatePlanes.takeAt( idx );
        disconnect( plane, nullptr, d, nullptr );
        disconnect( plane, nullptr, this, nullptr );
        plane->removeFromParentLayout();
        plane->setParent( nullptr );
        d->mouseClickedPlanes.removeAll(plane);
    }
    d->slotLayoutPlanes();
    // Need to Q_EMIT the signal: In case somebody has connected the signal
    // to her own slot for e.g. calling update() on a widget containing the chart.
    Q_EMIT propertiesChanged();
}

void Chart::setGlobalLeading( int left, int top, int right, int bottom )
{
    setGlobalLeadingLeft( left );
    setGlobalLeadingTop( top );
    setGlobalLeadingRight( right );
    setGlobalLeadingBottom( bottom );
}

void Chart::setGlobalLeadingLeft( int leading )
{
    d->globalLeadingLeft = leading;
    d->leftOuterSpacer->changeSize( leading, 0, QSizePolicy::Fixed, QSizePolicy::Minimum );
    d->reapplyInternalLayouts();
}

int Chart::globalLeadingLeft() const
{
    return d->globalLeadingLeft;
}

void Chart::setGlobalLeadingTop( int leading )
{
    d->globalLeadingTop = leading;
    d->topOuterSpacer->changeSize( 0, leading, QSizePolicy::Minimum, QSizePolicy::Fixed );
    d->reapplyInternalLayouts();
}

int Chart::globalLeadingTop() const
{
    return d->globalLeadingTop;
}

void Chart::setGlobalLeadingRight( int leading )
{
    d->globalLeadingRight = leading;
    d->rightOuterSpacer->changeSize( leading, 0, QSizePolicy::Fixed, QSizePolicy::Minimum );
    d->reapplyInternalLayouts();
}

int Chart::globalLeadingRight() const
{
    return d->globalLeadingRight;
}

void Chart::setGlobalLeadingBottom( int leading )
{
    d->globalLeadingBottom = leading;
    d->bottomOuterSpacer->changeSize( 0, leading, QSizePolicy::Minimum, QSizePolicy::Fixed );
    d->reapplyInternalLayouts();
}

int Chart::globalLeadingBottom() const
{
    return d->globalLeadingBottom;
}

void Chart::paint( QPainter* painter, const QRect& rect )
{
    if ( rect.isEmpty() || !painter ) {
        return;
    }

    QPaintDevice* prevDevice = GlobalMeasureScaling::paintDevice();
    GlobalMeasureScaling::setPaintDevice( painter->device() );
    int prevScaleFactor = PrintingParameters::scaleFactor();

    PrintingParameters::setScaleFactor( qreal( painter->device()->logicalDpiX() ) / qreal( logicalDpiX() ) );

    const QRect oldGeometry( geometry() );
    if ( oldGeometry != rect ) {
        setGeometry( rect );
        d->isPlanesLayoutDirty = true;
        d->isFloatingLegendsLayoutDirty = true;
    }
    painter->translate( rect.left(), rect.top() );
    d->paintAll( painter );

    // for debugging
    // painter->setPen( QPen( Qt::blue, 8 ) );
    // painter->drawRect( rect );

    painter->translate( -rect.left(), -rect.top() );
    if ( oldGeometry != rect ) {
        setGeometry( oldGeometry );
        d->isPlanesLayoutDirty = true;
        d->isFloatingLegendsLayoutDirty = true;
    }

    PrintingParameters::setScaleFactor( prevScaleFactor );
    GlobalMeasureScaling::setPaintDevice( prevDevice );
}

void Chart::resizeEvent ( QResizeEvent* event )
{
    d->isPlanesLayoutDirty = true;
    d->isFloatingLegendsLayoutDirty = true;
    QWidget::resizeEvent( event );
}

void Chart::reLayoutFloatingLegends()
{
    Q_FOREACH( Legend *legend, d->legends ) {
        const bool hidden = legend->isHidden() && legend->testAttribute( Qt::WA_WState_ExplicitShowHide );
        if ( legend->position().isFloating() && !hidden ) {
            // resize the legend
            const QSize legendSize( legend->sizeHint() );
            legend->setGeometry( QRect( legend->geometry().topLeft(), legendSize ) );
            // find the legends corner point (reference point plus any paddings)
            const RelativePosition relPos( legend->floatingPosition() );
            QPointF pt( relPos.calculatedPoint( size() ) );
            //qDebug() << pt;
            // calculate the legend's top left point
            const Qt::Alignment alignTopLeft = Qt::AlignBottom | Qt::AlignLeft;
            if ( (relPos.alignment() & alignTopLeft) != alignTopLeft ) {
                if ( relPos.alignment() & Qt::AlignRight )
                    pt.rx() -= legendSize.width();
                else if ( relPos.alignment() & Qt::AlignHCenter )
                    pt.rx() -= 0.5 * legendSize.width();

                if ( relPos.alignment() & Qt::AlignBottom )
                    pt.ry() -= legendSize.height();
                else if ( relPos.alignment() & Qt::AlignVCenter )
                    pt.ry() -= 0.5 * legendSize.height();
            }
            //qDebug() << pt << endl;
            legend->move( static_cast<int>(pt.x()), static_cast<int>(pt.y()) );
        }
    }
}


void Chart::paintEvent( QPaintEvent* )
{
    QPainter painter( this );
    d->paintAll( &painter );
    Q_EMIT finishedDrawing();
}

void Chart::addHeaderFooter( HeaderFooter* hf )
{
    Q_ASSERT( hf->type() == HeaderFooter::Header || hf->type() == HeaderFooter::Footer );
    int row;
    int column;
    getRowAndColumnForPosition( hf->position().value(), &row, &column );
    if ( row == -1 ) {
        qWarning( "Unknown header/footer position" );
        return;
    }

    d->headerFooters.append( hf );
    d->textLayoutItems.append( hf );
    connect( hf, SIGNAL(destroyedHeaderFooter(HeaderFooter*)),
             d, SLOT(slotUnregisterDestroyedHeaderFooter(HeaderFooter*)) );
    connect( hf, SIGNAL(positionChanged(HeaderFooter*)),
             d, SLOT(slotHeaderFooterPositionChanged(HeaderFooter*)) );

    // set the text attributes (why?)

    TextAttributes textAttrs( hf->textAttributes() );
    Measure measure( textAttrs.fontSize() );
    measure.setRelativeMode( this, KChartEnums::MeasureOrientationMinimum );
    measure.setValue( 20 );
    textAttrs.setFontSize( measure );
    hf->setTextAttributes( textAttrs );

    // add it to the appropriate layout

    int innerLayoutIdx = hf->type() == HeaderFooter::Header ? 0 : 1;
    QVBoxLayout* headerFooterLayout = d->innerHdFtLayouts[ innerLayoutIdx ][ row ][ column ];

    hf->setParentLayout( headerFooterLayout );
    hf->setAlignment( s_gridAlignments[ row ][ column ] );
    headerFooterLayout->addItem( hf );

    d->slotResizePlanes();
}

void Chart::replaceHeaderFooter( HeaderFooter* headerFooter,
                                 HeaderFooter* oldHeaderFooter_ )
{
    if ( headerFooter && oldHeaderFooter_ != headerFooter ) {
        HeaderFooter* oldHeaderFooter = oldHeaderFooter_;
        if ( d->headerFooters.count() ) {
            if ( ! oldHeaderFooter ) {
                oldHeaderFooter = d->headerFooters.first();
                if ( oldHeaderFooter == headerFooter )
                    return;
            }
            takeHeaderFooter( oldHeaderFooter );
        }
        delete oldHeaderFooter;
        addHeaderFooter( headerFooter );
    }
}

void Chart::takeHeaderFooter( HeaderFooter* headerFooter )
{
    const int idx = d->headerFooters.indexOf( headerFooter );
    if ( idx == -1 ) {
        return;
    }
    disconnect( headerFooter, SIGNAL(destroyedHeaderFooter(HeaderFooter*)),
                d, SLOT(slotUnregisterDestroyedHeaderFooter(HeaderFooter*)) );

    d->headerFooters.takeAt( idx );
    headerFooter->removeFromParentLayout();
    headerFooter->setParentLayout( nullptr );
    d->textLayoutItems.remove( d->textLayoutItems.indexOf( headerFooter ) );

    d->slotResizePlanes();
}

void Chart::Private::slotHeaderFooterPositionChanged( HeaderFooter* hf )
{
    chart->takeHeaderFooter( hf );
    chart->addHeaderFooter( hf );
}

HeaderFooter* Chart::headerFooter()
{
    if ( d->headerFooters.isEmpty() ) {
        return nullptr;
    } else {
        return d->headerFooters.first();
    }
}

HeaderFooterList Chart::headerFooters()
{
    return d->headerFooters;
}

void Chart::Private::slotLegendPositionChanged( AbstractAreaWidget* aw )
{
    Legend* legend = qobject_cast< Legend* >( aw );
    Q_ASSERT( legend );
    chart->takeLegend( legend );
    chart->addLegendInternal( legend, false );
}

void Chart::addLegend( Legend* legend )
{
    legend->show();
    addLegendInternal( legend, true );
    Q_EMIT propertiesChanged();
}

void Chart::addLegendInternal( Legend* legend, bool setMeasures )
{
    if ( !legend ) {
        return;
    }

    KChartEnums::PositionValue pos = legend->position().value();
    if ( pos == KChartEnums::PositionCenter ) {
       qWarning( "Not showing legend because PositionCenter is not supported for legends." );
    }

    int row;
    int column;
    getRowAndColumnForPosition( pos, &row, &column );
    if ( row < 0 && pos != KChartEnums::PositionFloating ) {
        qWarning( "Not showing legend because of unknown legend position." );
        return;
    }

    d->legends.append( legend );
    legend->setParent( this );

    // set text attributes (why?)

    if ( setMeasures ) {
        TextAttributes textAttrs( legend->textAttributes() );
        Measure measure( textAttrs.fontSize() );
        measure.setRelativeMode( this, KChartEnums::MeasureOrientationMinimum );
        measure.setValue( 20 );
        textAttrs.setFontSize( measure );
        legend->setTextAttributes( textAttrs );

        textAttrs = legend->titleTextAttributes();
        measure.setRelativeMode( this, KChartEnums::MeasureOrientationMinimum );
        measure.setValue( 24 );
        textAttrs.setFontSize( measure );

        legend->setTitleTextAttributes( textAttrs );
        legend->setReferenceArea( this );
    }

    // add it to the appropriate layout

    if ( pos != KChartEnums::PositionFloating ) {
        legend->needSizeHint();

        // in each edge and corner of the outer layout, there's a grid for the different alignments that we create
        // on demand. we don't remove it when empty.

        QLayoutItem* edgeItem = d->dataAndLegendLayout->itemAtPosition( row, column );
        QGridLayout* alignmentsLayout = dynamic_cast< QGridLayout* >( edgeItem );
        Q_ASSERT( !edgeItem || alignmentsLayout ); // if it exists, it must be a QGridLayout
        if ( !alignmentsLayout ) {
            alignmentsLayout = new QGridLayout;
            d->dataAndLegendLayout->addLayout( alignmentsLayout, row, column );
            alignmentsLayout->setContentsMargins( 0, 0, 0, 0 );
        }

        // in case there are several legends in the same edge or corner with the same alignment, they are stacked
        // vertically using a QVBoxLayout. it is created on demand as above.

        row = 1;
        column = 1;
        for ( int i = 0; i < 3; i++ ) {
            for ( int j = 0; j < 3; j++ ) {
                Qt::Alignment align = s_gridAlignments[ i ][ j ];
                if ( align == legend->alignment() ) {
                    row = i;
                    column = j;
                    break;
                }
            }
        }

        QLayoutItem* alignmentItem = alignmentsLayout->itemAtPosition( row, column );
        QVBoxLayout* sameAlignmentLayout = dynamic_cast< QVBoxLayout* >( alignmentItem );
        Q_ASSERT( !alignmentItem || sameAlignmentLayout ); // if it exists, it must be a QVBoxLayout
        if ( !sameAlignmentLayout ) {
            sameAlignmentLayout = new QVBoxLayout;
            alignmentsLayout->addLayout( sameAlignmentLayout, row, column );
            sameAlignmentLayout->setContentsMargins( 0, 0, 0, 0 );
        }

        sameAlignmentLayout->addItem( new MyWidgetItem( legend, legend->alignment() ) );
    }

    connect( legend, SIGNAL(destroyedLegend(Legend*)),
             d, SLOT(slotUnregisterDestroyedLegend(Legend*)) );
    connect( legend, SIGNAL(positionChanged(AbstractAreaWidget*)),
             d, SLOT(slotLegendPositionChanged(AbstractAreaWidget*)) );
    connect( legend, SIGNAL(propertiesChanged()), this, SIGNAL(propertiesChanged()) );

    d->slotResizePlanes();
}

void Chart::replaceLegend( Legend* legend, Legend* oldLegend_ )
{
    if ( legend && oldLegend_ != legend ) {
        Legend* oldLegend = oldLegend_;
        if ( d->legends.count() ) {
            if ( ! oldLegend ) {
                oldLegend = d->legends.first();
                if ( oldLegend == legend )
                    return;
            }
            takeLegend( oldLegend );
        }
        delete oldLegend;
        addLegend( legend );
    }
}

void Chart::takeLegend( Legend* legend )
{
    const int idx = d->legends.indexOf( legend );
    if ( idx == -1 ) {
        return;
    }

    d->legends.takeAt( idx );
    disconnect( legend, nullptr, d, nullptr );
    disconnect( legend, nullptr, this, nullptr );
    // the following removes the legend from its layout and destroys its MyWidgetItem (the link to the layout)
    legend->setParent( nullptr );

    d->slotResizePlanes();
    Q_EMIT propertiesChanged();
}

Legend* Chart::legend()
{
    return d->legends.isEmpty() ? nullptr : d->legends.first();
}

LegendList Chart::legends()
{
    return d->legends;
}

void Chart::mousePressEvent( QMouseEvent* event )
{
    const QPoint pos = mapFromGlobal( event->globalPos() );

    Q_FOREACH( AbstractCoordinatePlane* plane, d->coordinatePlanes ) {
        if ( plane->geometry().contains( event->pos() ) && plane->diagrams().size() > 0 ) {
            QMouseEvent ev( QEvent::MouseButtonPress, pos, event->globalPos(),
                            event->button(), event->buttons(), event->modifiers() );
            plane->mousePressEvent( &ev );
            d->mouseClickedPlanes.append( plane );
       }
    }
}

void Chart::mouseDoubleClickEvent( QMouseEvent* event )
{
    const QPoint pos = mapFromGlobal( event->globalPos() );

    Q_FOREACH( AbstractCoordinatePlane* plane, d->coordinatePlanes ) {
        if ( plane->geometry().contains( event->pos() ) && plane->diagrams().size() > 0 ) {
            QMouseEvent ev( QEvent::MouseButtonPress, pos, event->globalPos(),
                            event->button(), event->buttons(), event->modifiers() );
            plane->mouseDoubleClickEvent( &ev );
        }
    }
}

void Chart::mouseMoveEvent( QMouseEvent* event )
{
    QSet< AbstractCoordinatePlane* > eventReceivers = QSet< AbstractCoordinatePlane* >::fromList( d->mouseClickedPlanes );

    Q_FOREACH( AbstractCoordinatePlane* plane, d->coordinatePlanes ) {
        if ( plane->geometry().contains( event->pos() ) && plane->diagrams().size() > 0 ) {
            eventReceivers.insert( plane );
        }
    }

    const QPoint pos = mapFromGlobal( event->globalPos() );

    Q_FOREACH( AbstractCoordinatePlane* plane, eventReceivers ) {
        QMouseEvent ev( QEvent::MouseMove, pos, event->globalPos(),
                         event->button(), event->buttons(), event->modifiers() );
        plane->mouseMoveEvent( &ev );
    }
}

void Chart::mouseReleaseEvent( QMouseEvent* event )
{
    QSet< AbstractCoordinatePlane* > eventReceivers = QSet< AbstractCoordinatePlane* >::fromList( d->mouseClickedPlanes );

    Q_FOREACH( AbstractCoordinatePlane* plane, d->coordinatePlanes ) {
        if ( plane->geometry().contains( event->pos() ) && plane->diagrams().size() > 0 ) {
            eventReceivers.insert( plane );
        }
    }

    const QPoint pos = mapFromGlobal( event->globalPos() );

    Q_FOREACH( AbstractCoordinatePlane* plane, eventReceivers ) {
        QMouseEvent ev( QEvent::MouseButtonRelease, pos, event->globalPos(),
                         event->button(), event->buttons(), event->modifiers() );
        plane->mouseReleaseEvent( &ev );
    }

    d->mouseClickedPlanes.clear();
}

bool Chart::event( QEvent* event )
{
    if ( event->type() == QEvent::ToolTip ) {
        const QHelpEvent* const helpEvent = static_cast< QHelpEvent* >( event );
        Q_FOREACH( const AbstractCoordinatePlane* const plane, d->coordinatePlanes ) {
            // iterate diagrams in reverse, so that the top-most painted diagram is
            // queried first for a tooltip before the diagrams behind it
            const ConstAbstractDiagramList& diagrams = plane->diagrams();
            for (int i = diagrams.size() - 1; i >= 0; --i) {
                const AbstractDiagram* diagram = diagrams[i];
                if (diagram->isHidden()) {
                    continue;
                }
                const QModelIndex index = diagram->indexAt( helpEvent->pos() );
                const QVariant toolTip = index.data( Qt::ToolTipRole );
                if ( toolTip.isValid() ) {
                    QPoint pos = mapFromGlobal( helpEvent->pos() );
                    QRect rect( pos - QPoint( 1, 1 ), QSize( 3, 3 ) );
                    QToolTip::showText( QCursor::pos(), toolTip.toString(), this, rect );
                    return true;
                }
            }
        }
    }
    return QWidget::event( event );
}

bool Chart::useNewLayoutSystem() const
{
    return d_func()->useNewLayoutSystem;
}
void Chart::setUseNewLayoutSystem( bool value )
{
    if ( d_func()->useNewLayoutSystem != value )
        d_func()->useNewLayoutSystem = value;
}
