#ifndef TUTIL_INCLUDED
#define TUTIL_INCLUDED

#include "tcommon.h"
#include <math.h>

#ifdef _WIN32
#include <windows.h>
#include <winbase.h>
#endif

//! Type definition for a pair of double.
typedef std::pair<double, double> DoublePair;

//! Type definition for a pair of integer.
typedef std::pair<int, int> IntPair;

//! Square of x.
/*!
  \par x val to square
 */
template <class T>
inline T sq(T x)
{
	return x * x;
}

//! Calculates the floor of a value.
/*!
  Return the largest integer that is less than or equal to x.
  \par x val to floor
  \ret largest integer that is less than or equal to x
 */
inline int tfloor(double x)
{
	return ((int)(x) > (x) ? (int)(x)-1 : (int)(x));
}

//! Calculates the ceiling of a value.
/*!
  Return the smallest integer that is greater than or equal to x.
  \par x val to floor
  \ret smallest integer that is greater than or equal to x.
 */
inline int tceil(double x)
{
	return ((int)(x) < (x) ? (int)(x) + 1 : (int)(x));
}

//! Check if value is an integer.
/*!
  Return largest integer that is less than or equal to x
  \par x val to test
  \ret true if val is integer
 */
inline bool isInt(double x)
{
	return (int)(x) == (x);
}

inline int tfloor(int x, int step)
{
	return step * (x >= 0 ? (x / step) : -((-1 - x + step) / step));
}

inline int tceil(int x, int step)
{
	return step * (x >= 0 ? ((x + step - 1) / step) : -((-x) / step));
}

inline int intLE(double x)
{
	return tfloor(x);
}

inline int intGT(double x)
{
	return tfloor(x) + 1;
}

inline int intLT(double x)
{
	return tceil(x) - 1;
}

inline int intGE(double x)
{
	return tceil(x);
}

//! convert radiant to degree
/*!
  Convert an angle from radiant to angle.
  \par angle in radiant
  \ret angle in degree
 */
inline double rad2degree(double rad)
{
	return rad * TConsts::invOf_pi_180;
}

//! convert degree to radiant
/*!
  Convert an angle from degree to radiant.
  \par angle in degree
  \ret angle in radiant
 */
inline double degree2rad(double degree)
{
	return degree * TConsts::pi_180;
}

//! Sign of argument.
/*!
 Return sign of argument.
 \par arg value to test
 \ret -1 if arg is negative, 1 if arg is positive, 0 if arg is zero
 */
template <class T>
inline int tsign(T arg)
{
	return arg < 0 ? -1 : arg > 0 ? 1 : 0;
}

//! Check if two values are very similar.
/*!
  Check if two values are very similar.
  \par a first value
  \par b second value
  \par err max distance from value
  \ret bool if value are very similar.
 */
inline bool areAlmostEqual(double a, double b, double err = TConsts::epsilon)
{
	return fabs(a - b) < err;
}

//! Check if two values are very similar.
/*!
  Check if two values are very similar.
  \par a first value
  \par b second value
  \par err max distance from value
  \ret bool if value are very similar.
 */
template <class T>
inline bool areAlmostEqual(const T &a, const T &b, double err = TConsts::epsilon)
{
	return tdistance(a, b) < err;
}

struct TDeleteObjectFunctor {
	template <typename T>
	void operator()(T *ptr)
	{
		delete ptr;
	}
};

//! Clear a container deleting all elements.
/*!
  Clear a container, but before recall delete for all elements.
  \par c container
  \note the code doesn't work with map because it's impossible
        to deduce template
 */
template <class T>
inline void clearPointerContainer(T &c) throw()
{
	T tmp;
	std::for_each(c.begin(), c.end(), TDeleteObjectFunctor());
	c.swap(tmp);
}

#endif