#include <stdio.h>
#include <errno.h>
#include <ctype.h>
#include <stdlib.h>
#include <stdarg.h>
#include <strings.h>

#include "irdr.h"
#include "plot.h"
#include "istack.h"
#include "dirimpl.h"
#include "dir-output.h"

static char *lastfn = 0;

static char *new_fn(const char *prevfn)
{
 int l;
 int i;
 char *t;
 int dig;
 int dot;

 if (prevfn == 0) return(strdup("plot0001.pnm"));
 l = strlen(prevfn);
 t = malloc(l+2);
 bcopy(prevfn,t,l+1);
 dig = -1;
 dot = -1;
 for (i=0;i<l;i++)
  { if (isdigit((unsigned char)t[i])) dig = i;
    if (t[i] == '.') dot = i;
  }
 if (dig < 0)
  { if (dot < 0)
     { t[l++] = '1';
       t[l] = '\0';
       return(t);
     }
    bcopy(t+dot,t+dot+1,l+1-dot);
    t[dot] = '1';
    return(t);
  }
 while <"carry"> (dig >= 0)
  { switch (t[dig])
     { case '9':
	  t[dig] = '0';
	  dig --;
	  break;
       case '0': t[dig] = '1'; return(t); break;
       case '1': t[dig] = '2'; return(t); break;
       case '2': t[dig] = '3'; return(t); break;
       case '3': t[dig] = '4'; return(t); break;
       case '4': t[dig] = '5'; return(t); break;
       case '5': t[dig] = '6'; return(t); break;
       case '6': t[dig] = '7'; return(t); break;
       case '7': t[dig] = '8'; return(t); break;
       case '8': t[dig] = '9'; return(t); break;
       default:
	  break <"carry">;
     }
  }
 dig ++;
 bcopy(t+dig,t+dig+1,l+1-dot);
 t[dig] = '1';
 return(t);
}

DIRRV dir_output(void **privp __attribute__((__unused__)), DIROP op, ...)
{
 va_list ap;
 char *fn;
 FILE *f;

 va_start(ap,op);
 switch (op)
  { case DIROP_INIT:
       return(DIRRV_MORE);
       break;
    case DIROP_ARG:
       fn = va_arg(ap,char *);
       fn = fn ? strdup(fn) : new_fn(lastfn);
       f = fopen(fn,"w");
       if (! f)
	{ istack_err("%s: %s",fn,strerror(errno));
	  return(DIRRV_NOMORE);
	}
       plot_output(f);
       fclose(f);
       if (lastfn) free(lastfn);
       lastfn = fn;
       return(DIRRV_NOMORE);
       break;
  }
 va_end(ap);
 abort();
}