/*
 * $OpenXM: OpenXM_contrib2/asir2018/engine/p-itv.c,v 1.2 2018/09/28 08:20:28 noro Exp $
*/
#if defined(INTERVAL)
#include "ca.h"
#include "base.h"
#if defined(PARI)
#include "genpari.h"
#endif

extern int zerorewrite;

void itvtois(Itv a, Num *inf, Num *sup)
{
  if ( !a )
    *inf = *sup = (Num)0;
  else if ( NID(a) <= N_B ) {
    *inf = (Num)a; *sup = (Num)a;
  } else {
    *inf = INF(a);
    *sup = SUP(a);
  }
}

void istoitv(Num inf, Num sup, Itv *rp)
{
  Num  i, s;
  Itv c;
  int  type=0;

  if ( !inf && !sup ) {
    *rp = 0;
    return;
  }
  if ( !sup ) {
    s = 0;
  }
  else if ( NID( sup )==N_B ) {
    type = 1;
    ToBf(sup, (BF *)&s);
  } else {
    s = sup;
  }
  if ( !inf ) {
    i = 0;
  }
  else if ( NID( inf )==N_B ) {
    type = 1;
    ToBf(inf, (BF *)&i);
  } else {
    i = inf;
  }
  if ( type ) {
//    NEWIntervalBigFloat((IntervalBigFloat)c);
    c=MALLOC(sizeof(struct oIntervalBigFloat));
    OID(c)=O_N;
    NID(c)=N_IntervalBigFloat;
  } else 
    NEWItvP(c);

  if ( compnum(0,i,s) >= 0 ) {
    INF(c) = s; SUP(c) = i;
  } else {
    INF(c) = i; SUP(c) = s;
  }

  if (zerorewrite)
    if ( initvp(0,c) ) {
      *rp = 0;
      return;
    }
  *rp = c;
}

void additvp(Itv a, Itv b, Itv *c)
{
  Num  ai,as,bi,bs;
  Num  inf,sup;

  if ( !a )
    *c = b;
  else if ( !b )
    *c = a;
  else if ( (NID(a) <= N_B) && (NID(b) <= N_B ) )
    addnum(0,(Num)a,(Num)b,(Num *)c);
  else if ( (NID(a) == N_IP) && (NID(b) == N_R ) 
    ||(NID(a) == N_R ) && (NID(b) == N_IP) )
    additvd((Num)a,(Num)b,(IntervalDouble *)c);
  else {
    itvtois(a,&ai,&as);
    itvtois(b,&bi,&bs);
    addnum(0,ai,bi,&inf);
    addnum(0,as,bs,&sup);
    istoitv(inf,sup,c);
  }
}

void subitvp(Itv a, Itv b, Itv *c)
{
  Num  ai,as,bi,bs;
  Num  inf,sup;

  if ( !a )
    chsgnnum((Num)b,(Num *)c);
  else if ( !b )
    *c = a;
  else if ( (NID(a) <= N_B) && (NID(b) <= N_B ) )
    subnum(0,(Num)a,(Num)b,(Num *)c);
  else if ( (NID(a) == N_IP) && (NID(b) == N_R ) 
    ||(NID(a) == N_R ) && (NID(b) == N_IP) )
    subitvd((Num)a,(Num)b,(IntervalDouble *)c);
  else {
    itvtois(a,&ai,&as);
    itvtois(b,&bi,&bs);
    subnum(0,ai,bs,&inf);
    subnum(0,as,bi,&sup);
    istoitv(inf,sup,c);
  }
}

void mulitvp(Itv a, Itv b, Itv *c)
{
  Num  ai,as,bi,bs,a1,a2,b1,b2,c1,c2,p,t;
  int  ba,bb;

  if ( !a || !b )
    *c = 0;
  else if ( (NID(a) <= N_B) && (NID(b) <= N_B ) )
    mulnum(0,(Num)a,(Num)b,(Num *)c);
  else if ( (NID(a) == N_IP) && (NID(b) == N_R ) 
    ||(NID(a) == N_R ) && (NID(b) == N_IP) )
    mulitvd((Num)a,(Num)b,(IntervalDouble *)c);
  else {
    itvtois(a,&ai,&as);
    itvtois(b,&bi,&bs);
    chsgnnum(as,&a2);
    chsgnnum(bs,&b2);
    if ( ba = (compnum(0,0,a2) > 0) ) {
      a1 = ai;
    } else {
      a1 = a2;
      a2 = ai;
    }
    if ( bb = (compnum(0,0,b2) > 0) ) {
      b1 = bi;
    } else {
      b1 = b2;
      b2 = bi;
    }
    mulnum(0,a2,b2,&t);
    subnum(0,0,t,&c2);
    if ( compnum(0,0,b1) > 0 ) {
      mulnum(0,a2,b1,&t);
      subnum(0,0,t,&c1);
      if ( compnum(0,0,a1) > 0 ) {
        mulnum(0,a1,b2,&t);
        subnum(0,0,t,&p);
        if ( compnum(0,c1,p) > 0 ) c1 = p;
        mulnum(0,a1,b1,&t);
        subnum(0,0,t,&p);
        if ( compnum(0,c2,p) > 0 ) c2 = p;
      }
    } else {
      if ( compnum(0,0,a1) > 0 ) {
        mulnum(0,a1,b2,&t);
        subnum(0,0,t,&c1);
      } else {
        mulnum(0,a1,b1,&c1);
      }
    }
    if ( ba == bb ) {
      subnum(0,0,c2,&t);
      istoitv(c1,t,c);
    } else {
      subnum(0,0,c1,&t);
      istoitv(c2,t,c);
    }
  }
}

int     initvp(Num a, Itv b)
{
  Num inf, sup;

  itvtois(b, &inf, &sup);
  if ( compnum(0,inf,a) > 0 ) return 0;
  else if ( compnum(0,a,sup) > 0 ) return 0;
  else return 1;
}

int     itvinitvp(Itv a, Itv b)
{
  Num ai,as,bi,bs;

  itvtois(a, &ai, &as);
  itvtois(b, &bi, &bs);
  if ( compnum(0,ai,bi) >= 0  && compnum(0,bs,as) >= 0 ) return 1;
  else return 0;
}

void divitvp(Itv a, Itv b, Itv *c)
{
  Num  ai,as,bi,bs,a1,a2,b1,b2,c1,c2,t;
  int  ba,bb;

  if ( !b )
    error("divitv : division by 0");
  else if ( !a )
    *c = 0;
  else if ( (NID(a) <= N_B) && (NID(b) <= N_B ) )
    divnum(0,(Num)a,(Num)b,(Num *)c);
  else if ( (NID(a) == N_IP) && (NID(b) == N_R ) 
    ||(NID(a) == N_R ) && (NID(b) == N_IP) )
    divitvd((Num)a,(Num)b,(IntervalDouble *)c);
  else {
    itvtois(a,&ai,&as);
    itvtois(b,&bi,&bs);
    chsgnnum(as,&a2);
    chsgnnum(bs,&b2);
    if ( ba = (compnum(0,0,a2) > 0) ) {
      a1 = ai;
    } else {
      a1 = a2;
      a2 = ai;
    }
    if ( bb = (compnum(0,0,b2) > 0) ) {
      b1 = bi;
    } else {
      b1 = b2;
      b2 = bi;
    }
    if ( compnum(0,0,b1) >= 0 ) {
      error("divitv : division by interval including 0.");
    } else {
      divnum(0,a2,b1,&c2);
      if ( compnum(0,0,a1) > 0 ) {
        divnum(0,a1,b1,&c1);
      } else {
        divnum(0,a1,b2,&t);
        subnum(0,0,t,&c1);
      }
    }
    if ( ba == bb ) {
      subnum(0,0,c2,&t);
      istoitv(c1,t,c);
    } else {
      subnum(0,0,c1,&t);
      istoitv(c2,t,c);
    }
  }
}

void pwritvp(Itv a, Num e, Itv *c)
{
  int ei;
  Itv t;

  if ( !e )
    *c = (Itv)ONE;
  else if ( !a )
    *c = 0;
  else if ( NID(a) <= N_B )
    pwrnum(0,(Num)a,(Num)e,(Num *)c);
  else if ( !INT(e) ) {
#if defined(PARI) && 0
    gpui_ri((Obj)a,(Obj)c,(Obj *)c);
#else
    error("pwritv : can't calculate a fractional power");
#endif
  } else {
    ei = ZTOS((Q)e);
    pwritv0p(a,ei,&t);
    if ( SGN((Q)e) < 0 )
      divnum(0,(Num)ONE,(Num)t,(Num *)c);
    else
      *c = t;
  }
}

void pwritv0p(Itv a, int e, Itv *c)
{
  Num inf, sup;
  Num ai,Xmin,Xmax;
  Q  ne;

  if ( e == 1 )
    *c = a;
  else {
    STOZ(e,ne);
    if ( !(e%2) ) {
      if ( initvp(0,a) ) {
        Xmin = 0;
        chsgnnum(INF(a),&ai);
        if ( compnum(0,ai,SUP(a)) > 0 ) {
          Xmax = ai;
        } else {
          Xmax = SUP(a);
        }
      } else {
        if ( compnum(0,INF(a),0) > 0 ) {
          Xmin = INF(a);
          Xmax = SUP(a);
        } else {
          Xmin = SUP(a);
          Xmax = INF(a);
        }
      }
    } else {
      Xmin = INF(a);
      Xmax = SUP(a);
    }
    if ( ! Xmin )  inf = 0;
    else    pwrnum(0,Xmin,(Num)ne,&inf);
    pwrnum(0,Xmax,(Num)ne,&sup);
    istoitv(inf,sup,c);
  }
}

void chsgnitvp(Itv a, Itv *c)
{
  Num inf,sup;

  if ( !a )
    *c = 0;
  else if ( NID(a) <= N_B )
    chsgnnum((Num)a,(Num *)c);
  else {
    chsgnnum(INF((Itv)a),&inf);
    chsgnnum(SUP((Itv)a),&sup);
    istoitv(inf,sup,c);
  }
}

int cmpitvp(Itv a, Itv b)
{
  Num  ai,as,bi,bs;
  int  s,t;

  if ( !a ) {
    if ( !b || (NID(b)<=N_B) ) {
      return compnum(0,(Num)a,(Num)b);
    } else {
      itvtois(b,&bi,&bs);
      if ( compnum(0,(Num)a,bs) > 0 ) return 1;
      else if ( compnum(0,bi,(Num)a) > 0 ) return -1;
      else  return 0;
    }
  } else if ( !b ) {
    if ( !a || (NID(a)<=N_B) ) {
      return compnum(0,(Num)a,(Num)b);
    } else {
      itvtois(a,&ai,&as);
      if ( compnum(0,ai,(Num)b) > 0 ) return 1;
      else if ( compnum(0,(Num)b,as) > 0 ) return -1;
      else  return 0;
    }
  } else {
    itvtois(a,&ai,&as);
    itvtois(b,&bi,&bs);
    s = compnum(0,ai,bs) ;
    t = compnum(0,bi,as) ;
    if ( s > 0 ) return 1;
    else if ( t > 0 ) return -1;
    else  return 0;
  }
}

void miditvp(Itv a, Num *b)
{
  Num  ai,as;
  Num  t;

  if ( ! a ) *b = 0;
  else if ( (NID(a) <= N_B) )
    *b = (Num)a;
  else {
    STOZ(2,TWO);
    itvtois(a,&ai,&as);
    addnum(0,ai,as,&t);
    divnum(0,t,(Num)TWO,b);
  }
}

void cupitvp(Itv a, Itv b, Itv *c)
{
  Num  ai,as,bi,bs;
  Num  inf,sup;

  itvtois(a,&ai,&as);
  itvtois(b,&bi,&bs);
  if ( compnum(0,ai,bi) > 0 )  inf = bi;
  else        inf = ai;
  if ( compnum(0,as,bs) > 0 )  sup = as;
  else        sup = bs;
  istoitv(inf,sup,c);
}

void capitvp(Itv a, Itv b, Itv *c)
{
  Num  ai,as,bi,bs;
  Num  inf,sup;

  itvtois(a,&ai,&as);
  itvtois(b,&bi,&bs);
  if ( compnum(0,ai,bi) > 0 )  inf = ai;
  else        inf = bi;
  if ( compnum(0,as,bs) > 0 )  sup = bs;
  else        sup = as;
  if ( compnum(0,inf,sup) > 0 )  *c = 0;
  else        istoitv(inf,sup,c);
}


void widthitvp(Itv a, Num *b)
{
  Num  ai,as;

  if ( ! a ) *b = 0;
  else if ( (NID(a) <= N_B) )
    *b = (Num)a;
  else {
    itvtois(a,&ai,&as);
    subnum(0,as,ai,b);
  }
}

void absitvp(Itv a, Num *b)
{
  Num  ai,as,bi,bs;

  if ( ! a ) *b = 0;
  else if ( (NID(a) <= N_B) ) {
    if ( compnum(0,(Num)a,0) < 0 ) chsgnnum((Num)a,b);
    else *b = (Num)a;
  } else {
    itvtois(a,&ai,&as);
    if ( compnum(0,ai,0) < 0 ) chsgnnum(ai,&bi);
    else bi = ai;
    if ( compnum(0,as,0) < 0 ) chsgnnum(as,&bs);
    else bs = as;
    if ( compnum(0,bi,bs) > 0 )  *b = bi;
    else        *b = bs;
  }
}

void distanceitvp(Itv a, Itv b, Num *c)
{
  Num  ai,as,bi,bs;
  Num  di,ds;
  Itv  d;

  itvtois(a,&ai,&as);
  itvtois(b,&bi,&bs);
  subnum(0,ai,bi,&di);
  subnum(0,as,bs,&ds);
  istoitv(di,ds,&d);
  absitvp(d,c);
}

#endif