/* display.c                                */
/* ABZ 21/04/1990, 15/05/1990               */
/*                                          */
/* Output file using bold, underline, etc.  */
/* Interprets  *xxxx*  as bold              */
/*             _xxxx_  as underlined        */
/*  and bold generated by printing the same */
/* character in the same place several times*/
/* and underline by backspacing an underline*/
/* character, also some LaTeX {\xxxx word}  */
/* stuff for bold, etc.                     */
/* (The programming in this is atrocious    */
/* ... but it works.  I'll get round to a   */
/* proper re-write soon.)                   */

#include <stdio.h>
#include <ctype.h>
#define STDIN 0
#define STDOUT 1
#define STDERR 2

FILE *f_ptr=STDIN;
int c;
int lastc=0;
int under_flg=0; /* Not used */
int bold_flg=0; /* Not used */
int wrap=0;
int convert=0;
int xclude=0;
int column=0;

main(ac,av)
  unsigned ac;
  char *av[];
{
int here=1;

if ((av[1][0]=='-' & av[1][1]!='p' & av[1][1]!='o' & av[1][1]!='x')
	 | ac > 3 | av[2][0] == '-') {
  pr_string(STDERR,"Usage: ");
  pr_string(STDERR,av[0]);
  pr_string(STDERR," [-p|x|o] [filename]\n");
  exit(1);
  }
if (av[1][1]=='o' & av[1][0]=='-') {
  effect('0');
  exit(0);
  }
if (av[1][0]=='-' & av[1][1]=='x') { xclude++; here++; }
if (av[1][0]=='-' & av[1][1]=='p') { convert++; here++; }
if (av[here][0] != 0) {
  f_ptr=fopen(av[here],"r");
  if (f_ptr==NULL) {
    perror(av[here]); /* report error */
    exit(1);
    }
  }
while((c=get_a_char()) != EOF) {
  do_this_char();
  do_last();
  lastc=c;
  if (c<' ') { do_last(); }
  }
do_last();
if (f_ptr != STDIN) { fclose(f_ptr); }
}

do_this_char()
{
  if (c==8 & convert==0) { do_back(); }
  if (c=='_') { do_under(); } /* This must be after do_back */
  if (c=='*' && !isalpha(lastc) && xclude==0) {
    do_last(); lastc=c; c=get_a_char(); do_char('*','1'); }
  if (c=='{' & xclude==0) { do_curly(); }
}

do_last()
{
if (lastc != 0) { p_char(lastc); lastc=0; }
}

p_char(c)
int c;
{
if (c==9) {
  p_char(' ');
  while ((column & 7) != 0) { p_char(' '); }
  }
 else {
  if (c!=0) {
    if (c==13 || c==10) { column=0; }
     else { column++; }
    putchar(c);
    }
  }
}

do_tab()
{
do_last();
while ((column & 7) != 2) { p_char(' '); }
c=0;
}

get_a_char()
{
int c;

if (f_ptr != STDIN) { c=getc(f_ptr); }
  else { c=getchar(); }
return(c);
}

do_curly()  /* This copes with {\em bold} words */
{
int c2;
if ((c2=get_a_char()) != 92) {
  do_last();
  lastc=c;
  c=c2;
  do_this_char(); }
 else {
  if ((c2=get_a_char()) != 'e') {
    do_last();
    p_char('{');
    lastc=92;
    c=c2;
    do_this_char(); }
   else {
    if ((c2=get_a_char()) != 'm') {
      do_last();
      p_char('{');
      p_char(92);
      lastc='e';
      c=c2;
      do_this_char(); } 
     else {
      if ((c2=get_a_char()) != ' ') {
        do_last();
        p_char('{');
        p_char(92);
        p_char('e');
        lastc='m';
        c=c2;
        do_this_char(); }
       else {
        do_last(); c=0;
        do_char('}','1');
        c=0;
        }
      }
    }
  }
}

do_under() /* This copes with words underlined with a backspace */
{
int c2,c3;
c3=lastc;
do_last();
c2=get_a_char();
if (c2 == '_') {
  lastc=c2; c=c2; do_under();
  }
 else {
  if (c2 != 8) {
    lastc=c;
    c=c2; /* was <'!' */
    if (!isalpha(c3) & xclude==0) {
      do_char('_','4');  /* Try _underline_ */
      c3=get_a_char();
      if (isalpha(c3)) { /* _word_word_ intersperced '_' */
        if (convert==0) { effect('4'); }
        do_marked(' ','_','4');
        do_marked(c3,'_','4');
        lastc=0; do_under();
        }
       else {
        p_char(c);
        p_char(c3); /* _word_$ - real end of underline */
        c=0; }
      } /* end of yes-it's-a-letter and yes-I'm-converting */
    } /* end of underline followed by not-BS */
   else { /* Underline,BS */
    effect('4');
    p_char(get_a_char());
    effect('0');
    c=0; lastc=0;
    }
  }
}

do_back() /* Words made bold by backspacing */
{
int c2,c3;
c2=get_a_char();
while((c2=get_a_char()) == 8) { c3=get_a_char(); }
effect('1');
do_last();
effect('0');
c=c2;
}

do_char(marker,fx_code) /* *Bold* and _underline_  */
int marker,fx_code;     /* (Also end of {\em bold} */
{
int c2;
c2=get_a_char(); /* below used to have || c==39 for "'" */
if ((c2==marker && c2!='_') || c2<' ' || c==39 ||
    (c<'!' && c>0) || c=='.' || c==marker) {
  do_last();
  p_char(c); /* the quote, dot or marker */
  c=c2;
  }
 else {
  if (convert==0) { effect(fx_code); }
  if (c2=='_' && marker==c2) c2=' ';
  do_marked(c,marker,fx_code); do_marked(c2,marker,fx_code);
  while ((c2=get_a_char()) != marker & c2 != EOF)
    { do_marked(c2,marker,fx_code); }
  if (convert==0) { effect('0'); }
  lastc=0; c=0;
  }
}

do_marked(c,marker,fx_code)
int c,marker,fx_code;
{
if (c<' ') {
  if (convert==0) { effect('0'); }
  wrap=1;
  }
if (wrap==1 & c>' ') {
  if (convert==0) { effect(fx_code); }
  wrap=0;
  }
if (convert==0 | wrap==1) { p_char(c); }
  else {
  if (marker=='*' | marker=='}') { /* *Bold* */
    putchar(c); putchar(8); putchar(c); putchar(8);
    putchar(c); putchar(8); p_char(c);
    }
  if (marker=='_') { /* _Underline_ */
    putchar('_'); putchar(8); p_char(c);
    }
  }
}
 
effect(a)
int a;
{
putchar(27); putchar('['); putchar(a); putchar('m');
}

pr_string(out,s) /* Writes string to specific output */
char *s;
int out;
{
write (out,s,strlen(s));
}