#!/usr/local/bin/perl
#
# updates the index.html file in the current directory
# by including a listing of all the other html files in the directory.
#
# Uses the last-modified date stamp on each file to see if there is
# any work to do (ie if any other files are newer than index.html).
#
# If there's some text in the document titles that you *don't* want
# in the index, include it in $remove below, or with -remove on
# the commandline (eg -remove=xxx).
#
# Earl Fogel, July 1996


$startpat = "<!-- start of generated list - DO NOT REMOVE OR EDIT THIS LINE -->";
$endpat   = "<!-- end of generated list - DO NOT REMOVE OR EDIT THIS LINE   -->";

# use -remove=xxx to remove 'xxx' from all titles
# or define $remove (eg. $remove="xxx";)
while ($_ = $ARGV[0], /^-/) {
    shift;
    last if /^--$/;
    /^-remove=(.*)/ && ($remove=$1);
}

($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size,
    $atime,$mtime,$ctime,$blksize,$blocks)
	= stat("index.html");
$indexchangetime = $mtime if -r _;
$somethingtodo = 0;
while (<*.html>) {
    ($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size,
	$atime,$mtime,$ctime,$blksize,$blocks)
	    = stat($_);
    $somethingtodo=1 if $mtime > $indexchangetime;
#    print "$_ is newer\n" if $mtime > $indexchangetime;
}
exit if ! $somethingtodo;

# read in the existing file
open (INDEX, "index.html") || die("can't read index.html\n");
@index = <INDEX>;
close(INDEX);

# now create a new one
open (INDEX, ">index.html") || die("can't write index.html\n");

# check file for ending pattern
# if it's not there, we'll insert it
foreach $line (@index) {
    $OKendpat = 1 if $line =~ /$endpat/i;
}

foreach $line (@index) {
    $skipping = 0 if $line =~ /$endpat/i;
    print INDEX $line if ! $skipping;
    if ($line =~ /$startpat/i && ! $done) {
	&InsertList;
	print INDEX "$endpat\n\n" if ! $OKendpat;
	$done = 1;
	$skipping = 1 if $OKendpat;
    }
}

# if we can't find where it belongs, add it to the end of the file
if (! $done) {
    print INDEX "\n$startpat\n";
    &InsertList;
    print INDEX "$endpat\n\n";
}
close(INDEX);

sub InsertList {

    while (<*.html>) {
	next if /^index.html/;

	$fname = $_;
	$title = $fname;
	if (open (IN, $_)) {
	    while (<IN>) {
		if (s/.*<title>//i) {
		    chop;
		    s/$remove//i if defined($remove);
		    s/<.title>.*//i;
		    $title = $_;
		}
	    }
	    close(IN);
	    print INDEX "<a href=\"$fname\">$title</a><br>\n";
	}
    }
}