#!/usr/local/bin/perl
#
# Convert mod.recipes/alt.gourmand recipes source to HTML.
#	- Cameron Simpson <cs@zip.com.au> 17may95
#

$usemetric=1;	# preference
$usecelcius=1;	# preference
%macro=(
	RH => \&RH,
	RZ => \&RZ,
	IH => \&IH,
	IG => \&IG,
	SK => \&SK,
	PH => \&PH,
	NX => \&NX,
	WR => \&WR,
	PP => \&PP,
	SH => \&SH,
	TE => \&TE,
	IR => \&IR,
	AB => \&AB,
	IB => \&IB,
	I  => \&I,
	B => \&B,
	'sp' => \&sp,
       );

$didhdr=0;

while (<STDIN>)
	{ chomp;
	  $rc_line=$_;

	  if (/^\.\s*(\S\S?)\s*/)
		{ $dir=$1; $args=$';
		  @args=&args($args);

		  if (defined $macro{$dir})
			{ &{$macro{$dir}}(@args);
			}
		  else
		  { print STDERR "line $.: can't handle macro .$dir: ignoring $_\n";
		  }
		}
	  else
	  { &needhdr;
	    print &mkhtml($_), "\n";
	    print "<BR>\n" if $nofill;
	  }
	}

exit 0;

sub args
	{ local($_)=@_;
	  my(@args);

	  while (length)
		{ s/^\s+//;
		  if (/^'([^']*)'/
		   || /^"([^"]*)"/)
			{ push(@args,$1);
			  $_=$';
			}
		  elsif (/^\S+/)
			{ push(@args,$&);
			  $_=$';
			}
		}

	  for (@args)
		{ $_=&mkhtml($_); }

	  @args;
	}

sub nohdr
	{ if ($didhdr)
		{ print STDERR "line $.: header already printed\n";
		}
	}

sub needhdr
	{ if (! $didhdr)
		{ my($title)="$rc_key($rc_class) - $rc_name - $rc_source - $rc_date";
		  print "<TITLE>$title</TITLE>\n";
		  &H1("$rc_key($rec_class) - $rc_name");
		  print "$rc_name - $rc_desc\n";
		  &P;
		  $didhdr=1;
		}
	}

sub mkhtml
	{ local($_)=@_;
	  my($sofar,$code,$match);

	  while (/\\\*?(\\|\(..|[^\\\(])/)
		{ $code=$1;
		  $sofar.=$`;
		  $match=$&;
		  $_=$';

		  if ($code eq '\\')	{ $sofar.='\\'; }
		  elsif ($code eq '(12'){ $sofar.="&frac12;"; }
		  elsif ($code eq '(14'){ $sofar.="&frac14;"; }
		  elsif ($code eq '(34'){ $sofar.="&frac34;"; }
		  elsif ($code eq '(em'){ $sofar.="&mdash;"; }
		  elsif ($code eq '(de'){ $sofar.="&deg;"; }
		  elsif ($code eq '(mu'){ $sofar.="&mu;"; }
		  elsif ($code eq '-')
			{ $sofar.=$code;
			}
		  else
		  { print STDERR "line $.: unknown code \"$match\"\n";
		    $sofar.=$match;
		  }
		}

	  $_=$sofar.$_;

	  s/&/&amp;/g;
	  s/</&lt;/g;
	  s/>/&gt;/g;

	  $_;
	}

sub RH	{ &nohdr(); ($rc_source,$rc_key,$rc_class,$rc_date,$rc_year)=@_; }
sub RZ	{ &nohdr(); ($rc_name,$rc_desc)=@_; }
sub IH	{ &needhdr;
	  my($serves)=@_;
	  &H1("INGREDIENTS ($serves)");
	}
sub IG	{ &needhdr;
	  &inDL;
	  my($imperial,$ingredient,$metric)=@_;
	  print "<DT>",
		join(' ',
			grep(length,
			    $usemetric
			    ? ($metric, length($imperial) ? "($imperial)" : '')
			    : ($imperial, length($metric) ? "($metric)" : '')
			    )
		    ),
		"\n";
	  print "<DD><I>$ingredient</I>\n";
	}
sub SK	{ &inDL;
	  my($step)=@_;
	  print "<DT>($step)<DD>\n";
	}
sub PH	{ &H1("PROCEDURE @_"); }
sub NX	{ &H1("NOTES"); }
sub WR	{ &H1("CONTRIBUTOR"); $nofill=1; }
sub IR	{ print "<I>$_[0]</I>$_[1]\n"; }
sub SH	{ &H1("@_"); }
sub AB	{ my($imperial,$metric,$blah)=@_;
	  print $usemetric ? $metric : $imperial;
	  print " $blah" if length $blah;
	  print "\n";
	}
sub TE	{ my($fahr,$cels,$blah)=@_;
	  print $usecelcius ? "$cels&deg;C" : "$fahr&deg;F";
	  print " $blah" if length $blah;
	  print "\n";
	}

sub IB	{ my($rec,$cr)=@_;
	  print "<A HREF=".lc($rec).".html>$rec</A> $cr\n";
	}
sub H1	{ &outDL; print "<H1>@_</H1>\n"; }
sub P	{ print "<P>\n"; }
sub PP	{ print "<P>\n"; }
sub I	{ print "<I>@_<\I>\n"; }
sub B	{ print "<B>@_<\B>\n"; }
sub sp	{ print "<PRE>\n</PRE>\n"; }
sub inDL{ if (! $inDL)
		{ print "<DL>\n";
		  $inDL=1;
		}
	}
sub outDL{ if ($inDL)
		{ print "</DL>\n";
		  $inDL=0;
		}
	 }