#!/usr/bin/perl

# postconffix - add HTML paragraphs

# Basic operation:
#
# - Process input as text blocks separated by one or more empty
# (or all whitespace) lines.
#
# - Don't touch blocks that start with `<' in column zero.
#
# The only changes made are:
#
# - Put <p>..</p> around text blocks that start in column zero.
#
# - Put <pre>..</pre> around text blocks that start elsewhere.

#use Getopt::Std;

#$opt_h = undef;
#$opt_v = undef;
#getopts("hv");

#die "Usage: $0 [-hv]\n" if ($opt_h);

#push @ARGV, "/dev/null"; # XXX

while(<>) {

    # Pass through comments and blank linkes before a text block.
    if (/^(#|\s*$)/) {
	print;
	next;
    }

    # Gobble up the next text block.
    $block = "";
    do {
	$_ =~ s/\s+\n$/\n/;
	$block .= $_;
    } while(($_ = <>) && /\S/);

    # Don't touch a text block starting with < in column zero.
    if ($block =~ /^</) {
	print "$block\n";
    }

    # Meta block.
    elsif ($block =~ /^%/) {
	print "$block\n";
    }

    # Example block.
    elsif ($block =~ /^\S+\s=/) {
	print "<pre>\n$block</pre>\n\n";
    }

    # Pre-formatted block.
    elsif ($block =~ /^\s/) {
	print "<pre>\n$block</pre>\n\n";
    }

    # Paragraph block.
    elsif ($block =~ /^\S/) {
	print "<p>\n$block</p>\n\n";
    }

    # Can't happen.
    else {
	die "Unrecognized text block:\n$block";
    }
}