#ifndef TCURVES_UTIL_INCLUDED
#define TCURVES_UTIL_INCLUDED

//#include "tutil.h"
#include "tgeometry.h"

#undef DVAPI
#undef DVVAR
#ifdef TGEOMETRY_EXPORTS
#define DVAPI DV_EXPORT_API
#define DVVAR DV_EXPORT_VAR
#else
#define DVAPI DV_IMPORT_API
#define DVVAR DV_IMPORT_VAR
#endif

//=============================================================================
//forwards declarations

class TSegment;
class TQuadratic;
class TThickQuadratic;

//=============================================================================

/*! area (orientata) del trapeziode limitato dalla curva
    e dall'asse delle ascisse. L'area e' positiva se p(0),...p(t)...,p(1),p(0)
      viene percorso in senso antiorario 
DVAPI double getArea(const TQuadratic &curve);
*/

/*! Returns true if the min distance between \b point an \b segment is less o equal to \b distance
*/
DVAPI bool isCloseToSegment(const TPointD &point, const TSegment &segment, double distance);

/*!
  Compute min distance between a segment and a point
  */
DVAPI double tdistance(const TSegment &segment, const TPointD &point);
inline double tdistance(const TPointD &point, const TSegment &segment)
{
	return tdistance(segment, point);
}

/*!
  Compute intersection between segments; 
  return the number of intersections (0/1/2/-1) and add them
  (as a param couple) to the vector 'intersections'
  \note 
    if the segment intersections is larger than one point
    (i.e. the segments share a sub-segment) return 2 and 
    in vector there are extremes of sub-segment.
 */

DVAPI int intersect(const TPointD &seg1p0, const TPointD &seg1p1, const TPointD &seg2p0, const TPointD &seg2p1,
					std::vector<DoublePair> &intersections);

DVAPI int intersect(const TSegment &first,
					const TSegment &second,
					std::vector<DoublePair> &intersections);

/*!
  Compute intersection between quadratics; 
  return the number of intersections (0-4) and add them
  (as a param couple) to the vector 'intersections'
 */
DVAPI int intersect(const TQuadratic &q0,
					const TQuadratic &q1,
					std::vector<DoublePair> &intersections, bool checksegments = true);

/*!
  Compute intersection between and a segment; 
  return the number of intersections [0,2] and add them
  (as a param couple) to the vector 'intersections'.
  Remark:
    In pair "first" is for the first object and "second"
    its for the second.
 */
DVAPI int intersect(const TQuadratic &q,
					const TSegment &s,
					std::vector<DoublePair> &intersections,
					bool firstQuad = true);

inline int intersect(const TSegment &s,
					 const TQuadratic &q,
					 std::vector<DoublePair> &intersections)
{
	return intersect(q, s, intersections, false);
}

template <class T>
void split(const T &tq,
		   const std::vector<double> &pars,
		   std::vector<T *> &v)
{
	if (pars.empty())
		return;

	T *q1, q2;

	UINT i;

	q1 = new T();
	tq.split(pars[0], *q1, q2);
	v.push_back(q1);

	for (i = 1; i < pars.size(); ++i) {
		double newPar = (pars[i] - pars[i - 1]) / (1.0 - pars[i - 1]);

		q1 = new T();
		q2.split(newPar, *q1, q2);
		v.push_back(q1);
	}

	v.push_back(new T(q2));
}

template <class T>
void split(const T &tq, double w0, double w1, T &qOut)
{
	T q2;

	assert(w0 <= w1);

	if ((w1 - w0 == 0.0) && w0 == 1.0) {
		tq.split(w0, q2, qOut);
		return;
	}

	tq.split(w0, qOut, q2);

	double newPar = (w1 - w0) / (1.0 - w0);

	q2.split(newPar, qOut, q2);
}

DVAPI double computeStep(const TQuadratic &quad, double pixelSize);

DVAPI double computeStep(const TThickQuadratic &quad, double pixelSize);

//=============================================================================

/*!
  TQuadraticLengthEvaulator is an explicit length builder that for a specified
  quadratic.

  The purpose of a dedicated evaluator for the length of a quadratic is that of
  minimizing its computational cost.
  Both assigning a quadratic to the evaluator and retrieving its length up
  to a given parameter cost 1 sqrt and 1 log.
*/
class TQuadraticLengthEvaluator
{
	double m_c, m_e, m_f, m_sqrt_a_div_2, m_tRef, m_primitive_0;
	bool m_constantSpeed, m_noSpeed0, m_squareIntegrand;

public:
	TQuadraticLengthEvaluator() {}
	TQuadraticLengthEvaluator(const TQuadratic &quad) { setQuad(quad); }

	void setQuad(const TQuadratic &quad);
	double getLengthAt(double t) const;
};

#endif
//-----------------------------------------------------------------------------
//  End Of File
//-----------------------------------------------------------------------------