#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <locale.h>

/*	Author: Ruud Harmsen, 30 November 2024.
	Copyrighted in principle, but please do with it whatever you will.

 	This is a filter (stdin to stdout) that transforms a poem
	of the form Quasi-Alexandrinos (see
	https://rudhar.com/lingtics/intrlnga/poesia/quasalex.htm
	from a raw but easy to handle text form, like:
	word1 word2 -- word3 word4 word5
	to the HTML required to make it look good in a browser, like:
	<tr><td>word1 word2</td> <td>&ndash;</td> <td>word3 word4 word5</td></tr>
 */

static char sep[] = "--";

char linebuf[512];
int main (void)
{
   char *p, *p1, *p2, *p3, *p4;

   setlocale(LC_ALL, "C");

   while (fgets(linebuf, sizeof linebuf, stdin))
   {
      /* comment? */
      for (p1 = linebuf; *p1 && isspace(*p1); p1++)
         ;
      if (*p1 == '#')
         printf("%s", linebuf);
      /* normal line, one of three? */
      else if ((p = strstr(linebuf, sep)) != NULL)
      {
         for (p1 = linebuf; p1 < p && isspace(*p1); p1++)
            ;
         for (p2 = p; p2 > linebuf && isspace(p2[-1]); p2--)
            ;
         for (p3 = p + strlen(sep); *p3 && isspace(*p3); p3++)
            ;
         for (p4 = p + strlen(p); p4 > p3 && isspace(p4[-1]); p4--)
            ;
         printf("   <tr><td>%.*s</td> <td>&ndash;</td> <td>%.*s</td></tr>\n",
            p2 - p1, p1, p4 - p3, p3);
      }
      /* fourth line? */
      else
      {
         for (p1 = linebuf; *p1 && isspace(*p1); p1++)
            ;
         for (p2 = linebuf + strlen(linebuf);
              p2 > linebuf && isspace(p2[-1]); p2--)
            ;
         if (*p1)
            printf("   <tr><td>%.*s</td><td colspan=2></td></tr>\n",
               p2 - p1, p1);
         else
            printf("   <tr><td class=separastrophe colspan=3>&nbsp;</td></tr>\n\n");
      }
   }

   return 0;
}