/*
  interval.tcc -- implement Interval_t

  source file of the Flower Library

  (c) 1996, 1997--1998 Han-Wen Nienhuys <hanwen@cs.uu.nl>
*/


#ifndef INTERVAL_TCC
#define INTERVAL_TCC

#include <assert.h> 
#include <math.h>
#include "interval.hh"
#include "string.hh"
#include "flower-debug.hh"

template<class T>
void
Interval_t<T>::print () const
{
  fdebug << str ();
}

template<class T>
int
_Interval__compare (const Interval_t<T>&a,Interval_t<T> const&b)
{
  if (a.left == b.left && a.right == b.right)
	return 0;
  
  if (a.left <= b.left && a.right >= b.right)
	return 1;

  if (a.left >= b.left && a.right <= b.right)
	return -1;

  return -2;
}

template<class T>
bool 
Interval_t<T>::contains_b (Interval_t<T> const& a) const
{
  int c_i= _Interval__compare (*this, a);
  if (c_i == -2)
	return false;
  return c_i >= 0;
}

template<class T>
int
Interval__compare (const Interval_t<T>&a,Interval_t<T> const&b)
{
  int i = _Interval__compare (a,b);
  if (i < -1)
	assert (false);
  return i;
}

template<class T>
void
Interval_t<T>::set_empty()
{
  left = (T) infinity();
  right = (T) -infinity();
}

template<class T>
T
Interval_t<T>::length() const 
{
  if (right < left) 
    return 0;
  else 
    return right-left;
}

template<class T>
void
Interval_t<T>::unite (Interval_t<T> h)
{
  if (h.left<left)
	left = h.left;
  if (h.right>right)
	right = h.right;
}

/**
  smallest Interval which includes *this and #h#
 */

template<class T>
void
Interval_t<T>::intersect (Interval_t<T> h)
{
#if defined (__GNUG__) && ! defined (__STRICT_ANSI__)
  left = h.left >? left;
  right = h.right <?right;
#else
  left = max (h.left, left);
  right = min (h.right, right);
#endif
}

template<class T>
Interval_t<T>
intersect (Interval_t<T> x, Interval_t<T> const &y)
{
  x.intersect (y);
  return x;
}

template<class T>
String
Interval_t<T>::str() const
{
  if (empty_b())
	return "[empty]";
  String s ("[");
 
  return s + T_to_str (left) + String ("," ) + T_to_str (right ) + String ("]" );
}

template<class T>
bool
Interval_t<T>::elt_b (T r)
{
  return r >= left && r <= right;
}


#define INTERVAL__INSTANTIATE(T) struct Interval_t<T>;\
  template  int Interval__compare(const Interval_t<T>&,Interval_t<T> const&)

#endif // INTERVAL_TCC
