#pragma once

#include "Defines.h"

#include "iAlgMath_global.h"

class QPointF;
class QLineF;

// 几何基础类
class I_ALGMATH_EXPORT zxGmyBase
{
public:

    zxGmyBase();
    virtual ~zxGmyBase();

public:

    // ccw > 0
    double triangle_area(double ax, double ay, double bx, double by, double cx, double cy);

    // ccw > 0, cw < 0, empty = 0
    double triangle_ccw(double ax, double ay, double bx, double by, double cx, double cy);

    //
    double triangle_interpolate(double x1, double y1, double z1, double x2, double y2, double z2, double x3, double y3, double z3,double x, double y);

    // out < 0, cocircular = 0, in > 0
    double in_circle(double ax, double ay, double bx, double by, double cx, double cy, double dx, double dy);

    //         < 0
    //  a +--- = 0 ----+ b
    //         > 0
    double orient2d(double ax, double ay, double bx, double by, double cx, double cy);

    //     | d
    //     |
    // a --+--  b
    //     |
    //     | c
    bool is_segment_intersect(double ax, double ay, double bx, double by, double cx, double cy, double dx, double dy);

    // 角度
    double degToRad(double _deg);
    double radToDeg(double _rad);
    double kross(const QPointF& a, const QPointF& b);
    double lengthSquared(const QPointF& a);
    double pointSegmentDistanceSquared2D(const QPointF& q, const QPointF& p0, const QPointF& p1, double & t);
    double pointLineDistanceSquared2D(const QPointF& q, const QPointF& p0, const QPointF& p1, double & t);

    // 距离（有待优化）
    double dot(double ax, double ay, double bx, double by);
    double distance_squared(double ax, double ay, double bx, double by);
    double distance(double ax, double ay, double bx, double by);
    //double distance(double x0, double y0, double x1, double y1);
    double distanceSquared(double x0, double y0, double x1, double y1);
    double dot(const QPointF& a, const QPointF& b);

    int findIntersection(const QPointF& seg0_a, const QPointF& seg0_b, const QPointF& seg1_a, const QPointF& seg1_b, QPointF ip[2]);
    int findIntersection(const QLineF & seg0, const QLineF & seg1, QPointF ip[2]);

    void cubic_bezier(double & _x, double & _y, double t,
                      double _x0, double _y0, double _x1, double _y1,
                      double _x2, double _y2, double _x3, double _y3);

    bool polygonContainsPoint(const QVector<QPointF> & poly, double x, double y);
    bool polygonIsCcw(const QVector<QPointF> & poly);
    double polygonArea(const QVector<QPointF> & poly);
    void polygonSimplify(QVector<QPointF> & out, const QVector<QPointF> & in, double maxErrDistance2);

    int _findIntersection(double u0, double u1, double v0, double v1, double w[2]);
    void simplifyPolygonRdp(QVector<QPointF> & out, const QPointF in[], int in_count, int ia, int ib, double maxErrDistance2);

    // 计算pt到直线line的垂足。返回值表示垂足是否在线段内部（含端点）
    bool getPadel(const QPointF& pt, const QLineF& line, QPointF& ptPadel);

public:

    ///  @brief 计算直线距离
    static double calDistanceOf(QPointF pt1, QPointF pt2);

    ///  @brief 计算点P(x,y)与X轴正方向的夹角, 夹角弧度
    static double calRadToAxisX(double x, double y);

    ///  @brief 计算点P(x,y)与X轴正方向的夹角, 夹角°
    static double calAngleToAxisX(double x, double y);

    ///  @brief 点pt围绕点ptCenter旋转弧度fAngleR后的坐标,fAngleR 旋转弧度 or du，顺时针为正
    static QPointF rotatePt(QPointF pt, QPointF ptCenter, \
                            double fAngleR, bool bRad = true);

    ///  @brief 计算两点形成直线的倾斜角（0-180）
    static double calSlopeOf(QPointF pt1, QPointF pt2);

    ///  @brief 判断两条直线是否平行;
    static bool isParallelLines(QLineF line1, QLineF line2);

    ///  @brief 计算两条直线的距离（如果不平行，返回-1）;
    static double calDisOfLines(QLineF line1, QLineF line2);

    ///  @brief 计算两条直线/线段的相交点坐标;
    /// bOnlySegment:true 只考虑线段，false考虑直线，即线段延长线
    static bool calCrossOfLines(QPointF& ptCross, \
                                QLineF line1, QLineF line2, \
                                bool bOnlySegment = false);

    ///  @brief 计算点到直线距离
    static double calDisOfPt2Line(QPointF pt, QLineF line);
    static double calDisOfPt2Line(QPointF pt, \
                                    QPointF pt1, QPointF pt2);

    // y = kx + b
    static double leastSquareMethodSlop(int cnt,const double x[],const double y[],double &b);
    static double leastSquareMethodSlopEx(int cnt,const double x[],const double y[],double &b);

};