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#ifndef QTRIANGULATINGSTROKER_P_H

#define QTRIANGULATINGSTROKER_P_H

#include <private/qdatabuffer_p.h>

#include <private/qvectorpath_p.h>

#include <private/qbezier_p.h>

#include <private/qnumeric_p.h>

#include <private/qmath_p.h>

class QTriangulatingStroker

{

public:

    void process(const QVectorPath &path, const QPen &pen);

    inline int vertexCount() const { return m_vertices.size(); }

    inline const float *vertices() const { return m_vertices.data(); }

    inline void setInvScale(qreal invScale) { m_inv_scale = invScale; }

private:

    inline void emitLineSegment(float x, float y, float nx, float ny);

    inline void moveTo(const qreal *pts);

    inline void lineTo(const qreal *pts);

    void cubicTo(const qreal *pts);

    inline void join(const qreal *pts);

    inline void normalVector(float x1, float y1, float x2, float y2, float *nx, float *ny);

    inline void endCap(const qreal *pts);

    inline void arc(float x, float y);

    void endCapOrJoinClosed(const qreal *start, const qreal *cur, bool implicitClose, bool endsAtStart);

    QDataBuffer<float> m_vertices;

    float m_cx, m_cy;           // current points

    float m_nvx, m_nvy;         // normal vector...

    float m_width;

    qreal m_miter_limit;

    int m_roundness;            // Number of line segments in a round join

    qreal m_sin_theta;          // sin(m_roundness / 360);

    qreal m_cos_theta;          // cos(m_roundness / 360);

    qreal m_inv_scale;

    float m_curvyness_mul;

    float m_curvyness_add;

    Qt::PenJoinStyle m_join_style;

    Qt::PenCapStyle m_cap_style;

};

class QDashedStrokeProcessor

{

public:

    QDashedStrokeProcessor();

    void process(const QVectorPath &path, const QPen &pen);

    inline void addElement(QPainterPath::ElementType type, qreal x, qreal y) {

        m_points.add(x);

        m_points.add(y);

        m_types.add(type);

    }

    inline int elementCount() const { return m_types.size(); }

    inline qreal *points() const { return m_points.data(); }

    inline QPainterPath::ElementType *elementTypes() const { return m_types.data(); }

    inline void setInvScale(qreal invScale) { m_inv_scale = invScale; }

private:

    QDataBuffer<qreal> m_points;

    QDataBuffer<QPainterPath::ElementType> m_types;

    QDashStroker m_dash_stroker;

    qreal m_inv_scale;

};

inline void QTriangulatingStroker::normalVector(float x1, float y1, float x2, float y2,

                                                float *nx, float *ny)

{

    float dx = x2 - x1;

    float dy = y2 - y1;

    float pw = m_width / sqrt(dx*dx + dy*dy);

    *nx = -dy * pw;

    *ny = dx * pw;

}

inline void QTriangulatingStroker::emitLineSegment(float x, float y, float vx, float vy)

{

    m_vertices.add(x + vx);

    m_vertices.add(y + vy);

    m_vertices.add(x - vx);

    m_vertices.add(y - vy);

}

// We draw a full circle for any round join or round cap which is a

// bit of overkill...

inline void QTriangulatingStroker::arc(float x, float y)

{

    float dx = m_width;

    float dy = 0;

    for (int i=0; i<=m_roundness; ++i) {

        float tmpx = dx * m_cos_theta - dy * m_sin_theta;

        float tmpy = dx * m_sin_theta + dy * m_cos_theta;

        dx = tmpx;

        dy = tmpy;

        emitLineSegment(x, y, dx, dy);

    }

}

inline void QTriangulatingStroker::endCap(const qreal *pts)

{

    switch (m_cap_style) {

    case Qt::FlatCap:

        break;

    case Qt::SquareCap: {

        float dx = m_cx - *(pts - 2);

        float dy = m_cy - *(pts - 1);

        float len = m_width / sqrt(dx * dx + dy * dy);

        dx = dx * len;

        dy = dy * len;

        emitLineSegment(m_cx + dx, m_cy + dy, m_nvx, m_nvy);

        break; }

    case Qt::RoundCap:

        arc(m_cx, m_cy);

        break;

    default: break; // to shut gcc up...

    }

    int count = m_vertices.size();

    m_vertices.add(m_vertices.at(count-2));

    m_vertices.add(m_vertices.at(count-1));

}

void QTriangulatingStroker::moveTo(const qreal *pts)

{

    m_cx = pts[0];

    m_cy = pts[1];

    float x2 = pts[2];

    float y2 = pts[3];

    normalVector(m_cx, m_cy, x2, y2, &m_nvx, &m_nvy);

    // To acheive jumps we insert zero-area tringles. This is done by

    // adding two identical points in both the end of previous strip

    // and beginning of next strip

    bool invisibleJump = m_vertices.size();

    switch (m_cap_style) {

    case Qt::FlatCap:

        if (invisibleJump) {

            m_vertices.add(m_cx + m_nvx);

            m_vertices.add(m_cy + m_nvy);

        }

        break;

    case Qt::SquareCap: {

        float dx = x2 - m_cx;

        float dy = y2 - m_cy;

        float len = m_width / sqrt(dx * dx + dy * dy);

        dx = dx * len;

        dy = dy * len;

        float sx = m_cx - dx;

        float sy = m_cy - dy;

        if (invisibleJump) {

            m_vertices.add(sx + m_nvx);

            m_vertices.add(sy + m_nvy);

        }

        emitLineSegment(sx, sy, m_nvx, m_nvy);

        break; }

    case Qt::RoundCap:

        if (invisibleJump) {

            m_vertices.add(m_cx + m_nvx);

            m_vertices.add(m_cy + m_nvy);

        }

        // This emitLineSegment is not needed for the arc, but we need

        // to start where we put the invisibleJump vertex, otherwise

        // we'll have visible triangles between subpaths.

        emitLineSegment(m_cx, m_cy, m_nvx, m_nvy);

        arc(m_cx, m_cy);

        break;

    default: break; // ssssh gcc...

    }

    emitLineSegment(m_cx, m_cy, m_nvx, m_nvy);

}

void QTriangulatingStroker::lineTo(const qreal *pts)

{

    emitLineSegment(pts[0], pts[1], m_nvx, m_nvy);

    m_cx = pts[0];

    m_cy = pts[1];

}

void QTriangulatingStroker::join(const qreal *pts)

{

    // Creates a join to the next segment (m_cx, m_cy) -> (pts[0], pts[1])

    normalVector(m_cx, m_cy, pts[0], pts[1], &m_nvx, &m_nvy);

    switch (m_join_style) {

    case Qt::BevelJoin:

        break;

    case Qt::MiterJoin: {

        int p1 = m_vertices.size() - 6;

        int p2 = m_vertices.size() - 2;

        QLineF line(m_vertices.at(p1), m_vertices.at(p1+1),

                    m_vertices.at(p2), m_vertices.at(p2+1));

        QLineF nextLine(m_cx - m_nvx, m_cy - m_nvy,

                        pts[0] - m_nvx, pts[1] - m_nvy);

        QPointF isect;

        if (line.intersect(nextLine, &isect) != QLineF::NoIntersection

            && QLineF(line.p2(), isect).length() <= m_miter_limit) {

            // The intersection point mirrored over the m_cx, m_cy point

            m_vertices.add(m_cx - (isect.x() - m_cx));

            m_vertices.add(m_cy - (isect.y() - m_cy));

            // The intersection point

            m_vertices.add(isect.x());

            m_vertices.add(isect.y());

        }

        // else

        // Do a plain bevel join if the miter limit is exceeded or if

        // the lines are parallel. This is not what the raster

        // engine's stroker does, but it is both faster and similar to

        // what some other graphics API's do.

        break; }

    case Qt::RoundJoin:

        arc(m_cx, m_cy);

        break;

    default: break; // gcc warn--

    }

    emitLineSegment(m_cx, m_cy, m_nvx, m_nvy);

}

#endif