: # *-*-perl-*-*
    eval 'exec perl -S $0 "$@"'
    if $running_under_some_shell;

#
# HTML-sum.pl
#
# $Id: HTML-sum.pl,v 2.2 2000/02/03 12:45:55 sxw Exp $
#
# andy powell <a.powell@ukoln.ac.uk>
#
#############################################################################
#
#  Harvest Indexer http://harvest.sourceforge.net/
#  -----------------------------------------------
#
#  The Harvest Indexer is a continued development of code developed by
#  the Harvest Project. Development is carried out by numerous individuals
#  in the Internet community, and is not officially connected with the
#  original Harvest Project or its funding sources.
#
#  Please mail lee@arco.de if you are interested in participating
#  in the development effort.
#
#  This program is free software; you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation; either version 2 of the License, or
#  (at your option) any later version.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with this program; if not, write to the Free Software
#  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#
#########################################################################
#
# Parse HTML file to generate SOIF record on STDOUT
#
# Usage: HTML-sum.pl [-u URL] filename
#
# Giving the -u URL option causes a complete SOIF record to be generated
# incluing an opening
#
# @FILE { URL
#
# and a closing
#
# }
#
# Otherwise a simple list of SOIF attributes is generated which is what
# Harvest expects from HTML-sum.pl.

$ENV{'HARVEST_HOME'} = "/usr/local/harvest" if (!defined($ENV{'HARVEST_HOME'}));
unshift(@INC, "$ENV{'HARVEST_HOME'}/lib");      # use local files
require "soif.pl";
require HTML::Parser;
use Getopt::Std;
use HTML::Entities ();

package P; @ISA = qw(HTML::Parser);

# Change these as desired...
#
$createURLTexts = 1; # Create SOIF 'url-texts' attribute to match
                     # 'url-references'
$createComments = 1; # Create SOIF 'comments' attribute from HTML comments
$createScriptLanguages = 1; # Create SOIF 'script-languages' attribute to
                     # indicate scripting languages used on page
$createApplets = 1;  # Create SOIF 'applets' attribute from HTML applet tags
$splitFullText = 1;  # Add blank lines to SOIF 'full-text' attribute on some
                     # tags - may help with later text processing of SOIF
                     # record?
@paraTags = (        # List of tags that cause a paragraph break...
    'title',
    'h1',
    'h2',
    'h3',
    'h4',
    'h5',
    'h6',
    'p',
    'ul',
    'ol',
    'dl',
    'pre',
    'div',
    'center',
    'blockquote',
    'form',
    'hr',
    'table',
);
@keytags = (         # List of tags that go into SOIF keywords...
    'b',
    'i',
    'a',
    'em',
    'h1',
    'h2',
    'h3',
    'h4',
    'h5',
    'h6',
);

Getopt::Std::getopts('u:');
$url = $Getopt::Std::opt_u;
die "Usage: HTML-sum.pl [-u URL] filename" unless ($file = shift(@ARGV));

# Called for each opening HTML tag
#
sub start
{
    my($self, $tag, $attr) = @_;
    my($name, $content, $href, $code, $alt, $src);
    if ($tag eq 'title') {
	$titletext++;
    }
    if ($tag =~ /^h[1-6]$/) {
	$headingstext++;
    }
    if (grep(/^$tag$/, @keytags)) {
	$keywordstext++;
    }
    if ($tag eq 'meta') {
	for (keys %$attr) {
	    $name = $attr->{$_} if (/^name$/i);
	    $content = $attr->{$_} if (/^content$/i);
	}
	$name =~ tr/A-Z/a-z/; # ignore case of name
	if ($name eq 'keywords') { # Treat this specially - we'll use it
				   # later to over-ride generated value
	    push(@metakeywords, $content);
	}
	else {
	    push(@metaname, $name) unless $meta{$name};
	    $meta{$name} .= "$content\n";
	}
    }
    if ($tag eq 'a') {
	for (keys %$attr) {
	    $href = $attr->{$_} if (/^href$/i);
	}
	push(@soif'urlreferences, $href);
	$urltext++;
    }
    if ($tag eq 'script') {
	for (keys %$attr) {
	    $lang = $attr->{$_} if (/^language$/i);
	}
	$soif'scriptlanguages{$lang}++;
	$inscript++;
    }
    if (grep(/^$tag$/, @paraTags)) {
	push(@soif'fulltext, "\n") if $splitFullText;
    }
    if ($tag eq 'applet') {
	for (keys %$attr) {
	    $code = $attr->{$_} if (/^code$/i);
	}
	push(@soif'applets, $code);
    }
    if ($tag eq 'img') {
	for (keys %$attr) {
	    $alt = $attr->{$_} if (/^alt$/i);
	    $src = $attr->{$_} if (/^src$/i);
	}
	push(@soif'fulltext, "\n\n$alt\n\n");
	push(@soif'urlreferences, $src);
	push(@soif'urltexts, "$alt\n");
    }
}

# Called for each closing HTML tag
#
sub end
{
    my($self, $tag) = @_;
    if ($tag eq 'title') {
	$titletext--;
	undef $titletext if ($titletext < 0);
    }
    if ($tag =~ /^h[1-6]$/) {
	$headingstext--;
	undef $headingstext if ($headingstext < 0);
    }
    if (grep(/^$tag$/, @keytags)) {
	$keywordstext--;
	undef $keywordstext if ($keywordstext < 0);
    }
    if ($tag eq 'a') {
	push(@soif'urltexts, "\n");
	$urltext--;
	undef $urltext if ($urltext < 0);
    }
    if ($tag eq 'script') {
	$inscript--;
	undef $inscript if ($inscript < 0);
    }
    if (grep(/^$tag$/, @paraTags)) {
	push(@soif'fulltext, "\n") if $splitFullText;
    }
}

# Called for each bit of text
#
sub text
{
    my $self = shift;
    my $t = $_[0];
    return if $inscript; # Chuck out any script text
    # Strip leading newline
    $t =~ s/^\n+//;
#    $t =~ s/\s+/ /g;
    # Multiple spaces or tabs to single space...
    $t =~ s/[ \t]+/ /g;
    # Multiple newlines to single newline...
    $t =~ s/\n+/\n/g;
    # Throw out whitespace only lines
    return if ($t =~ /^\s*$/);
    $t = HTML::Entities::decode_entities($t);
    if ($t) {
	push(@soif'fulltext, $t);
	# Remove leading and trailing whitespace...
	$t =~ s/^\s*//;
	$t =~ s/\s*$//;
	push(@soif'title, $t) if $titletext;
	push(@soif'headings, $t) if $headingstext;
	$soif'keywords{$t}++ if $keywordstext;
	push(@soif'urltexts, $t) if $urltext;
    }
}

# Called for each HTML comment
#
sub comment
{
    my $self = shift;
    return if $inscript; # Chuck out any script text
    push(@soif'comments, $_[0]);
}

# Parse the HTML file
#
$p = new P;
$p->parse_file($file);

# Generate SOIF attribute/values
#
print "\@FILE { $url\n" if $url;
&soif'print_av('title', join(" ", @soif'title)) if @soif'title;
&soif'print_av('headings', join("\n", @soif'headings)) if @soif'headings;
foreach (keys %soif'keywords) {
    push(@soif'keywords, $_);
}
@soif'keywords = @metakeywords if (@metakeywords);
&soif'print_av('keywords', join("\n", sort @soif'keywords)) if @soif'keywords;
if (@soif'fulltext) {
    $tmp = join("\n", @soif'fulltext);
    $tmp =~ s/\n\n+/\n\n/g;
    $tmp =~ s/^\s*//;
    $tmp =~ s/\s*$//;
    &soif'print_av('full-text', $tmp);
}
&soif'print_av('url-references', join("\n", @soif'urlreferences)) if @soif'urlreferences;
if (@soif'urltexts && $createURLTexts) {
    $tmp = join("", @soif'urltexts);
    $tmp =~ s/^\s*//;
    $tmp =~ s/\s*$//;
    &soif'print_av('url-texts', $tmp);
}
foreach (@metaname) {
    $meta{$_} =~ s/\s+$//;
    &soif'print_av($_, $meta{$_});
}
&soif'print_av('comments', join("\n", @soif'comments)) if (@soif'comments && $createComments);
foreach (keys %soif'scriptlanguages) {
    push(@soif'scriptlanguages, $_);
}
&soif'print_av('script-languages', join("\n", sort @soif'scriptlanguages)) if (@soif'scriptlanguages && $createScriptLanguages);
&soif'print_av('applets', join("\n", sort @soif'applets)) if (@soif'applets && $createApplets);
print "}\n" if $url;