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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"

#ifndef QT_NO_GRAPHICSVIEW

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 {

    enum Type {

        Normal = 0,

        Pair

    };

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

        : m_item(item), m_edge(edge), m_type(Normal) {}

    AnchorVertex()

        : m_item(0), m_edge(Qt::AnchorPoint(0)), m_type(Normal) {}

#ifdef QT_DEBUG

    inline QString toString() const;

#endif

    QGraphicsLayoutItem *m_item;

    Qt::AnchorPoint m_edge;

    uint m_type : 1;

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

    // Value is calculated from the current anchors sizes.

    qreal distance;

};

/*!

  \internal

  Represents an edge (anchor) in the internal graph.

*/

struct AnchorData : public QSimplexVariable {

    enum Type {

        Normal = 0,

        Sequential,

        Parallel

    };

    enum Dependency {

        Independent = 0,

        Master,

        Slave

    };

    AnchorData()

        : QSimplexVariable(), from(0), to(0),

          minSize(0), prefSize(0), maxSize(0),

          minPrefSize(0), maxPrefSize(0),

          sizeAtMinimum(0), sizeAtPreferred(0),

          sizeAtMaximum(0), item(0), graphicsAnchor(0),

          type(Normal), isLayoutAnchor(false),

          isCenterAnchor(false), orientation(0),

          dependency(Independent) {}

    virtual ~AnchorData();

    virtual void updateChildrenSizes() {}

    void refreshSizeHints(const QLayoutStyleInfo *styleInfo = 0);

#ifdef QT_DEBUG

    void dump(int indent = 2);

    inline QString toString() const;

    QString name;

#endif

    // Anchor is semantically directed

    AnchorVertex *from;

    AnchorVertex *to;

    // Nominal sizes

    // These are the intrinsic size restrictions for a given item. They are

    // used as input for the calculation of the actual sizes.

    // These values are filled by the refreshSizeHints method, based on the

    // anchor size policy, the size hints of the item it (possibly) represents

    // and the layout spacing information.

    qreal minSize;

    qreal prefSize;

    qreal maxSize;

    qreal minPrefSize;

    qreal maxPrefSize;

    // Calculated sizes

    // These attributes define which sizes should that anchor be in when the

    // layout is at its minimum, preferred or maximum sizes. Values are

    // calculated by the Simplex solver based on the current layout setup.

    qreal sizeAtMinimum;

    qreal sizeAtPreferred;

    qreal sizeAtMaximum;

    // References to the classes that represent this anchor in the public world

    // An anchor may represent a LayoutItem, it may also be acessible externally

    // through a GraphicsAnchor "handler".

    QGraphicsLayoutItem *item;

    QGraphicsAnchor *graphicsAnchor;

    uint type : 2;            // either Normal, Sequential or Parallel

    uint isLayoutAnchor : 1;  // if this anchor is an internal layout anchor

    uint isCenterAnchor : 1;

    uint orientation : 1;

    uint dependency : 2;      // either Independent, Master or Slave

};

#ifdef QT_DEBUG

inline QString AnchorData::toString() const

{

    return QString::fromAscii("Anchor(%1)").arg(name);

}

#endif

struct SequentialAnchorData : public AnchorData

{

    SequentialAnchorData(const QVector<AnchorVertex *> &vertices, const QVector<AnchorData *> &edges)

        : AnchorData(), m_children(vertices), m_edges(edges)

    {

        type = AnchorData::Sequential;

        orientation = m_edges.at(0)->orientation;

#ifdef QT_DEBUG

        name = QString::fromAscii("%1 -- %2").arg(vertices.first()->toString(), vertices.last()->toString());

#endif

    }

    virtual void updateChildrenSizes();

    void calculateSizeHints();

    QVector<AnchorVertex*> m_children;          // list of vertices in the sequence

    QVector<AnchorData*> m_edges;               // keep the list of edges too.

};

struct ParallelAnchorData : public AnchorData

{

    ParallelAnchorData(AnchorData *first, AnchorData *second)

        : AnchorData(), firstEdge(first), secondEdge(second)

    {

        type = AnchorData::Parallel;

        orientation = first->orientation;

        // This assert whether the child anchors share their vertices

        Q_ASSERT(((first->from == second->from) && (first->to == second->to)) ||

                 ((first->from == second->to) && (first->to == second->from)));

        // Our convention will be that the parallel group anchor will have the same

        // direction as the first anchor.

        from = first->from;

        to = first->to;

#ifdef QT_DEBUG

        name = QString::fromAscii("%1 | %2").arg(first->toString(), second->toString());

#endif

    }

    virtual void updateChildrenSizes();

    bool calculateSizeHints();

    bool secondForward() const {

        // We have the convention that the first children will define the direction of the

        // pararell group. Note that we can't rely on 'this->from' or 'this->to'  because they

        // might be changed by vertex simplification.

        return firstEdge->from == secondEdge->from;

    }

    AnchorData* firstEdge;

    AnchorData* secondEdge;

    QList<QSimplexConstraint *> m_firstConstraints;

    QList<QSimplexConstraint *> m_secondConstraints;

};

struct AnchorVertexPair : public AnchorVertex {

    AnchorVertexPair(AnchorVertex *v1, AnchorVertex *v2, AnchorData *data)

        : AnchorVertex(), m_first(v1), m_second(v2), m_removedAnchor(data) {

        m_type = AnchorVertex::Pair;

    }

    AnchorVertex *m_first;

    AnchorVertex *m_second;

    AnchorData *m_removedAnchor;

    QList<AnchorData *> m_firstAnchors;

    QList<AnchorData *> m_secondAnchors;

};

#ifdef QT_DEBUG

inline QString AnchorVertex::toString() const

{

    if (!this) {

        return QLatin1String("NULL");

    } else if (m_type == Pair) {

        const AnchorVertexPair *vp = static_cast<const AnchorVertexPair *>(this);

        return QString::fromAscii("(%1, %2)").arg(vp->m_first->toString()).arg(vp->m_second->toString());

    } else if (!m_item) {

        return QString::fromAscii("NULL_%1").arg(quintptr(this));

    }

    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;

    // Size information for user controlled anchor

    QSizePolicy::Policy sizePolicy;

    qreal preferredSize;

    uint hasSize : 1;         // if false, get size from style.

};

/*!

  \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 {

        MinimumToMinPreferred = 0,

        MinPreferredToPreferred,

        PreferredToMaxPreferred,

        MaxPreferredToMaximum

    };

    // 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);

    QLayoutStyleInfo &styleInfo() const;

    AnchorData *addAnchorMaybeParallel(AnchorData *newAnchor, bool *feasible);

    // Activation

    void calculateGraphs();

    void calculateGraphs(Orientation orientation);

    // Simplification

    bool simplifyGraph(Orientation orientation);

    bool simplifyVertices(Orientation orientation);

    bool simplifyGraphIteration(Orientation orientation, bool *feasible);

    bool replaceVertex(Orientation orientation, AnchorVertex *oldV,

                       AnchorVertex *newV, const QList<AnchorData *> &edges);

    void restoreSimplifiedGraph(Orientation orientation);

    void restoreSimplifiedAnchor(AnchorData *edge);

    void restoreSimplifiedConstraints(ParallelAnchorData *parallel);

    void restoreVertices(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);

    // Support functions for calculateGraph()

    void refreshAllSizeHints(Orientation orientation);

    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));

    }

    inline void changeLayoutVertex(Orientation orientation, AnchorVertex *oldV, AnchorVertex *newV)

    {