#!__PERL__

$rcsId=' $Id: build_docbook_index.prl,v 1.2 2001/04/04 13:11:27 awb Exp $ ';

=head1 build_html_index [-v]

=over 4

=item Created by

    Richard Caley, Sun Feb 14 1999

=item Last Modification

    $Date: 2001/04/04 13:11:27 $ by $Author: awb $

=item Locked by

    $Locker:  $

=back

=cut

sub useage
{
    print <<END;
    Useage:
	build_html_index [-v|-h] -m MODE -t TITLE IFILE OFILE

	-m MODE		MODE (html only at the moment)
	-t TITLE	Title for the index.
	IFILE		File produced by jade.
	OFILE		Docbook index is put in this file
END
}

#__SHARED_SETUP__

$title='';
$mode='debug';
$verbose=0;

while ($#ARGV>=0)
	{
	if ($ARGV[0] eq '-v')
	      {
	      $verbose++;
	      shift @ARGV;
	      }
	elsif ($ARGV[0] eq '-t')
	      {
	      shift @ARGV;
	      $title=shift @ARGV;
	      }
	elsif ($ARGV[0] eq '-m')
	      {
	      shift @ARGV;
	      $mode=shift @ARGV;
	      }
	elsif ($ARGV[0] eq '-h')
	      {
	      useage();
	      exit 0;
	      }
	else
		{
		last;
		}
	}

if ($#ARGV != 1)
    {
    useage();
    exit(1);
    }

if (!defined(&{"print_tree_as_$mode"}))
    {
    useage();
    exit(1);
    }


$datafile= shift @ARGV;
$indexfile= shift @ARGV;

open(DATA, $datafile) ||
    die "can't open $datafile - $!";

open(INDEX, ">$indexfile") ||
    die "can't create $indexfile - $!";

@entries=();

while(<DATA>)
    {
    if (/^INDEXTERM\s+(.*)/)
	{
	$current = {};
	$$current{INDEXTERM}=$1;
	}
    elsif (/^\/INDEXTERM/)
	{
	push(@entries, $current);
	}
    elsif (/^([a-z]+)\s+(.*)/i)
	{
	$$current{lc $1}=$2;
	}
    }

close(DATA);


@entries = sort entry_order @entries;

$tree=build_tree(\@entries);

&{"print_tree_as_$mode"}($tree, INDEX);

close(INDEX);

exit 0;

sub entry_order
{
    my ($o) = lc $$a{primary} cmp lc $$b{primary};

    $o = (lc $$a{secondary} cmp lc $$b{secondary})
	if $o ==0;

    $o = (lc $$a{tertiary} cmp lc $$b{tertiary})
	if $o ==0;

    $o = (lc $$a{id} cmp lc $$b{id})
	if $o ==0;

    return $o;
}

sub build_tree
{
    my ($entries) = @_;

    my ($root) = [];

    foreach $e (@$entries)
	{
	if ($#$root<0 || $$e{primary} ne $root->[$#$root][0])
	    {
	    push (@$root, [ $$e{primary}, []]);
	    }
	my ($p) = $root->[$#$root][1];

	if ($#$p<0 || $$e{secondary} ne $p->[$#$p][0])
	    {
	    push (@$p, [ $$e{secondary}, []]);
	    }
	my ($s) = $p->[$#$p][1];

	if ($#$s<0 || $$e{tertiary} ne $s->[$#$s][0])
	    {
	    push (@$s, [ $$e{tertiary}, []]);
	    }
	my ($t) = $s->[$#$s][1];

	push(@$t, $e);
	}

    return $root;
}

sub print_tree_as_debug
{
    my ($root) = @_;

    print "[\n";
    foreach $p (@$root)
	{
	print $$p[0], "\n";
	print "  [\n";
	foreach $s (@{$$p[1]})
	    {
	    print "  ", $$s[0], "\n";
	    print "    [\n";
	    foreach $t (@{$$s[1]})
		{
		print "    ", $$t[0], "\n";
		print "      {";
		foreach $e (@{$$t[1]})
		    {
		    print " $$e{id}";
		    }
		print "}\n";
		}
	    print "    ]\n";
	    }
	print "  ]\n";
	}
    print "]\n";
}

sub print_tree_as_html
{
    my ($root, $s) = @_;

    my ($div) = '';

    print $s "<index>\n";
    print $s "<title>$title</title>\n"
	if $title;
    foreach $p (@$root)
	{
	my ($pname) = $$p[0];

	my ($initial) = lc substr($pname, 0, 1);
	if ($initial ne $div)
	    {
	    print $s "</indexdiv>"
		if $div;
	    print $s "<indexdiv> <title> $initial </title>\n";
	    $div=$initial;
	    }
	print $s "  <indexentry>\n";
	print_node($s, $p, "    ", "primary", "secondary", "tertiary");
	print $s "  </indexentry>\n";
	}
    print $s "</indexdiv>\n"
	if $div;
    print $s "</index>\n";
}

sub print_node
{
    my ($s, $node, $ind, $which, @rest) = @_;

    my ($name) = $$node[0];
    my ($bits) = $$node[1];
    my ($i)=0;
    my (@links) = ();

    unless (ref($bits->[0]) eq 'ARRAY' && $bits->[0]->[0])
	{
	$i++;

	@links = @{get_links($bits)};
	}

    print_ie($s, $ind, $which, \@links, $name);

    if ($#rest >=0)
	{
	my ($next) = shift @rest;

	for(; $i <= $#$bits; $i++)
	    {
	    print_node($s, $$bits[$i], $ind."  ", $next, @rest);
	    }
	}
}

sub print_ie
{
    my ($s, $ind, $which, $links, $name) = @_;

    my ($c) =1;
    my ($lab) = $name;

    print $s "$ind<${which}ie>";
    if ($#$links >=0 )
	{
	foreach $e (@$links)
	    {
	    print $s "<link linkend='$$e{id}'>$lab</link> ";
	    $c++;
	    $lab = "ref $c";
	    }
	}
    else
	{
	print $s "$lab";
	}
    print $s "</${which}ie>\n";
}

sub get_links
{
    my ($node) = @_;

    while (ref($$node[0]) eq 'ARRAY')
	{
	$node = $node->[0]->[1];
	}
    return $node;
}


sub setup
{
}