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#ifndef QGRAPHICSANCHORLAYOUT_P_H

#define QGRAPHICSANCHORLAYOUT_P_H

//

//  W A R N I N G

//  -------------

//

// This file is not part of the Qt API.  It exists purely as an

// implementation detail.  This header file may change from version to

// version without notice, or even be removed.

//

// We mean it.

//

#include <QGraphicsWidget>

#include <private/qobject_p.h>

#include "qgraphicslayout_p.h"

#include "qgraphicsanchorlayout.h"

#include "qgraph_p.h"

#include "qsimplex_p.h"

QT_BEGIN_NAMESPACE

/*

  The public QGraphicsAnchorLayout interface represents an anchorage point

  as a pair of a <QGraphicsLayoutItem *> and a <Qt::AnchorPoint>.

  Internally though, it has a graph of anchorage points (vertices) and

  anchors (edges), represented by the AnchorVertex and AnchorData structs

  respectively.

*/

/*!

  \internal

  Represents a vertex (anchorage point) in the internal graph

*/

struct AnchorVertex {

    AnchorVertex(QGraphicsLayoutItem *item, Qt::AnchorPoint edge)

    AnchorVertex()

#ifdef QT_DEBUG

    inline QString toString() const;

#endif

    QGraphicsLayoutItem *m_item;

    Qt::AnchorPoint m_edge;

    // Current distance from this vertex to the layout edge (Left or Top)

    // Value is calculated from the current anchors sizes.

    qreal distance;

};

#ifdef QT_DEBUG

inline QString AnchorVertex::toString() const

{

        return QLatin1String("NULL");

    }

    QString edge;

    switch (m_edge) {

    case Qt::AnchorLeft:

        edge = QLatin1String("Left");

        break;

    case Qt::AnchorHorizontalCenter:

        edge = QLatin1String("HorizontalCenter");

        break;

    case Qt::AnchorRight:

        edge = QLatin1String("Right");

        break;

    case Qt::AnchorTop:

        edge = QLatin1String("Top");

        break;

    case Qt::AnchorVerticalCenter:

        edge = QLatin1String("VerticalCenter");

        break;

    case Qt::AnchorBottom:

        edge = QLatin1String("Bottom");

        break;

    default:

        edge = QLatin1String("None");

        break;

    }

    QString itemName;

    if (m_item->isLayout()) {

        itemName = QLatin1String("layout");

    } else {

        if (QGraphicsItem *item = m_item->graphicsItem()) {

            itemName = item->data(0).toString();

        }

    }

    edge.insert(0, QLatin1String("%1_"));

    return edge.arg(itemName);

}

#endif

/*!

  \internal

  Representation of a valid path for a given vertex in the graph.

  In this struct, "positives" is the set of anchors that have been

  traversed in the forward direction, while "negatives" is the set

  with the ones walked backwards.

  This paths are compared against each other to produce LP Constraints,

  the exact order in which the anchors were traversed is not relevant.

*/

class GraphPath

{

public:

    GraphPath() {}

    QSimplexConstraint *constraint(const GraphPath &path) const;

#ifdef QT_DEBUG

    QString toString() const;

#endif

    QSet<AnchorData *> positives;

    QSet<AnchorData *> negatives;

};

class QGraphicsAnchorLayoutPrivate;

/*!

    \internal

*/

class QGraphicsAnchorPrivate : public QObjectPrivate

{

    Q_DECLARE_PUBLIC(QGraphicsAnchor)

public:

    explicit QGraphicsAnchorPrivate(int version = QObjectPrivateVersion);

    ~QGraphicsAnchorPrivate();

    void setSpacing(qreal value);

    void unsetSpacing();

    qreal spacing() const;

    void setSizePolicy(QSizePolicy::Policy policy);

    QGraphicsAnchorLayoutPrivate *layoutPrivate;

    AnchorData *data;

    QSizePolicy::Policy sizePolicy;

};

/*!

  \internal

  QGraphicsAnchorLayout private methods and attributes.

*/

class Q_AUTOTEST_EXPORT QGraphicsAnchorLayoutPrivate : public QGraphicsLayoutPrivate

{

    Q_DECLARE_PUBLIC(QGraphicsAnchorLayout)

public:

    // When the layout geometry is different from its Minimum, Preferred

    // or Maximum values, interpolation is used to calculate the geometries

    // of the items.

    //

    // Interval represents which interpolation interval are we operating in.

    enum Interval {

    };

    // Several structures internal to the layout are duplicated to handle

    // both Horizontal and Vertical restrictions.

    //

    // Orientation is used to reference the right structure in each context

    enum Orientation {

        Horizontal = 0,

        Vertical,

        NOrientations

    };

    QGraphicsAnchorLayoutPrivate();

    static QGraphicsAnchorLayoutPrivate *get(QGraphicsAnchorLayout *q)

    {

        return q ? q->d_func() : 0;

    }

    static Qt::AnchorPoint oppositeEdge(

        Qt::AnchorPoint edge);

    static Orientation edgeOrientation(Qt::AnchorPoint edge);

    static Qt::AnchorPoint pickEdge(Qt::AnchorPoint edge, Orientation orientation)

    {

        if (orientation == Vertical && int(edge) <= 2)

            return (Qt::AnchorPoint)(edge + 3);

        else if (orientation == Horizontal && int(edge) >= 3) {

            return (Qt::AnchorPoint)(edge - 3);

        }

        return edge;

    }

    // Init methods

    void createLayoutEdges();

    void deleteLayoutEdges();

    void createItemEdges(QGraphicsLayoutItem *item);

    void createCenterAnchors(QGraphicsLayoutItem *item, Qt::AnchorPoint centerEdge);

    void removeCenterAnchors(QGraphicsLayoutItem *item, Qt::AnchorPoint centerEdge, bool substitute = true);

    void removeCenterConstraints(QGraphicsLayoutItem *item, Orientation orientation);

    QGraphicsAnchor *acquireGraphicsAnchor(AnchorData *data)

    {

        Q_Q(QGraphicsAnchorLayout);

        if (!data->graphicsAnchor) {

            data->graphicsAnchor = new QGraphicsAnchor(q);

            data->graphicsAnchor->d_func()->data = data;

        }

        return data->graphicsAnchor;

    }

    // function used by the 4 API functions

    QGraphicsAnchor *addAnchor(QGraphicsLayoutItem *firstItem,

                            Qt::AnchorPoint firstEdge,

                            QGraphicsLayoutItem *secondItem,

                            Qt::AnchorPoint secondEdge,

                            qreal *spacing = 0);

    // Helper for Anchor Manipulation methods

    void addAnchor_helper(QGraphicsLayoutItem *firstItem,

                   Qt::AnchorPoint firstEdge,

                   QGraphicsLayoutItem *secondItem,

                   Qt::AnchorPoint secondEdge,

                   AnchorData *data);

    QGraphicsAnchor *getAnchor(QGraphicsLayoutItem *firstItem, Qt::AnchorPoint firstEdge,

                               QGraphicsLayoutItem *secondItem, Qt::AnchorPoint secondEdge);

    void removeAnchor(AnchorVertex *firstVertex, AnchorVertex *secondVertex);

    void removeAnchor_helper(AnchorVertex *v1, AnchorVertex *v2);

    void removeAnchors(QGraphicsLayoutItem *item);

    void removeVertex(QGraphicsLayoutItem *item, Qt::AnchorPoint edge);

    void correctEdgeDirection(QGraphicsLayoutItem *&firstItem,

                              Qt::AnchorPoint &firstEdge,

                              QGraphicsLayoutItem *&secondItem,

                              Qt::AnchorPoint &secondEdge);

    void calculateGraphs();

    void calculateGraphs(Orientation orientation);

    bool calculateTrunk(Orientation orientation, const GraphPath &trunkPath,

                        const QList<QSimplexConstraint *> &constraints,

                        const QList<AnchorData *> &variables);

    bool calculateNonTrunk(const QList<QSimplexConstraint *> &constraints,

                           const QList<AnchorData *> &variables);

    void findPaths(Orientation orientation);

    void constraintsFromPaths(Orientation orientation);

    void updateAnchorSizes(Orientation orientation);

    QList<QSimplexConstraint *> constraintsFromSizeHints(const QList<AnchorData *> &anchors);

    QList<QList<QSimplexConstraint *> > getGraphParts(Orientation orientation);

    void identifyFloatItems(const QSet<AnchorData *> &visited, Orientation orientation);

    void identifyNonFloatItems_helper(const AnchorData *ad, QSet<QGraphicsLayoutItem *> *nonFloatingItemsIdentifiedSoFar);

    inline AnchorVertex *internalVertex(const QPair<QGraphicsLayoutItem*, Qt::AnchorPoint> &itemEdge) const

    {

        return m_vertexList.value(itemEdge).first;

    }

    inline AnchorVertex *internalVertex(const QGraphicsLayoutItem *item, Qt::AnchorPoint edge) const

    {

        return internalVertex(qMakePair(const_cast<QGraphicsLayoutItem *>(item), edge));

    }