/****************************************************************************
** COPYRIGHT (C):    1997 Cay S. Horstmann. All Rights Reserved.
** PROJECT:          Practical OO Development with C++ and Java
** FILE:             setfmt.cpp
** PURPOSE:          setformat manipulator
** VERSION           1.0
** PROGRAMMERS:      Cay Horstmann (CSH)
** RELEASE DATE:     3-15-97 (CSH)
** UPDATE HISTORY:
****************************************************************************/

#include "setup.h"
#include <ctype.h>
#include <stdlib.h>

EXPORT ostream& do_setformat(ostream& os, const char* fmt)
{  int i = 0;
   while (fmt[i] != 0)
   {  if (fmt[i] != '%') { os << fmt[i]; i++; }
      else
      {  i++;
         if (fmt[i] == '%') { os << fmt[i]; i++; }
         else
         {  bool ok = true;
            int istart = i;
            bool more = true;
            int width = 0;
            int precision = 6;
            long flags = 0;
            char fill = ' ';
            bool alternate = false;
            while (more)
            {  switch (fmt[i])
               {  case '+':
                     flags |= ios::showpos;
                     break;
                  case '-':
                     flags |= ios::left;
                     break;
                  case '0':
                     flags |= ios::internal;
                     fill = '0';
                     break;
                  case '#':
                     alternate = true;
                     break;
                  case ' ':
                     break;
                  default:
                     more = false;
                     break;
               }
               if (more) i++;
            }
            if (isdigit(fmt[i])) 
            {  width = atoi(fmt+i); 
               do i++; while (isdigit(fmt[i]));
            }
            if (fmt[i] == '.')
            {  i++;
               precision = atoi(fmt+i); 
               while (isdigit(fmt[i])) i++;
            }
            switch (fmt[i])
            {  case 'd':
                  flags |= ios::dec;
                  break;
               case 'x':
                  flags |= ios::hex;
                  if (alternate) flags |= ios::showbase;
                  break;
               case 'X':
                  flags |= ios::hex | ios::uppercase;
                  if (alternate) flags |= ios::showbase;
                  break;
               case 'o':
                  flags |= ios::hex;
                  if (alternate) flags |= ios::showbase;
                  break;
               case 'f':
                  flags |= ios::fixed;
                  if (alternate) flags |= ios::showpoint;
                  break;
               case 'e':
                  flags |= ios::scientific;
                  if (alternate) flags |= ios::showpoint;
                  break;
               case 'E':
                  flags |= ios::scientific | ios::uppercase;
                  if (alternate) flags |= ios::showpoint;
                  break;
               case 'g':
                  if (alternate) flags |= ios::showpoint;
                  break;
               case 'G':
                  flags |= ios::uppercase;
                  if (alternate) flags |= ios::showpoint;
                  break;
               default:
                  ok = false;
               break;
            }
            i++;
            if (fmt[i] != 0) ok = false;
            if (ok)
            {  os.unsetf(ios::adjustfield | ios::basefield | ios::floatfield);
               os.setf(flags);
               os.width(width);
               os.precision(precision);
               os.fill(fill);
            }
            else i = istart;
         }
      }
   }
   return os;
}

EXPORT template <class S, class T>
class Manipulator
{
public:
   typedef S& (*Action)(S&, T);
   Manipulator(Action a, T v) { _action = a; _value = v; }
friend S& operator<<(S&, const Manipulator&);
private:
  Action _action;
  T _value;
};

EXPORT template <class S, class T>
inline S& operator<<(S& s, const Manipulator<S, T>& m)
{  (*m._action)(s, m._value);
   return s;
}

EXPORT inline Manipulator<ostream, const char*> setformat(const char* s)
{  return Manipulator<ostream, const char*>(do_setformat, s);
}