#!/usr/bin/perl -w -T
# rss_news.pl - Read from RSS Feeds and produce
# a web page.
# Note: This is not guaranteed to work on all
# RSS feeds.  It does not break on the ones listed.
# See this at work at
# http://barcelona.pm.org/news.cgi

use strict;

use XML::RSS;
use LWP::Simple qw(get);
use CGI qw(:standard escapeHTML);
# warningsToBrowser may not work in your version--
# if so, use comment this declaration and use the
# next one. Also, remove the fatalsToBrowser for a
# production site if you're worried about
# security.
use CGI::Carp qw(fatalsToBrowser warningsToBrowser);
#use CGI::Carp qw(fatalsToBrowser);

my $cgi = new CGI; # Hash reference
print $cgi->header()."\n\n";
# If warningsToBrowser doesn't work in your version,
# comment the next line.
warningsToBrowser(1);
print $cgi->start_html("news feeds")."\n\n";

# Read and process the channels listed at the
# end of the file.
my @channels;
while (<DATA>)
{
	push(@channels, $_);
}
map {get_channel($_, $cgi)} (@channels);

print $cgi->end_html()."\n";

sub get_channel
{
	# This subroutine takes a URL and a CGI object
	# and prints out the resulting RSS feed formatted
	# as HTML

	my ($url, $q) = @_;
	my $version = "1.0";

	# Use LWP::Simple to get the RSS feed.
	my $content = get($url) or carp("I couldn't get from $url");
	# Just to be sure...
	if ($content =~ m/^\s*$/)
	{
		carp("$url is empty");
		return;
	}

	# Determine the version based on regexes-- 
	# I based these on the feeds I was familiar
	# with, so this part could be improved by
	# finding the standard for this information
	if ($content =~ m#http://my.netscape.com/rdf/simple/0.9/#i)
	{
		$version = "0.9";
		print $q->comment("$url: RDF version 0.9")."\n";
	}
	elsif ($content =~ m#<rss version="0.91">#i)
	{
		$version = "0.91";
		print $q->comment("$url: RDF version 0.91")."\n";
	}
	else
	{
		print $q->comment("$url: looks like RDF version 1.0")."\n";
	}
	# Create the new rss object with this version
	my $result = new XML::RSS (version => "$version");

	# Parse the content
	$result->parse($content) or carp("I couldn't parse $url");

	# Channel Title
	my $channel = $result->{'channel'}; # Hash reference
	print $q->comment("This page was generated from $url.")."\n\n";
	print $q->h1("News from ".
		$q->a( { -href => $channel->{'link'}},
		$channel->{'title'}))."\n";
	print $q->h2($channel->{'description'})."\n";

	# Channel Image
	my $image = $result->{'image'}; # Hash reference
	if ($image->{'title'} ne "")
	{
		print $q->a( { -href => $image->{'link'}},
			img( { -src => $image->{'url'},
			-alt => $image->{'title'}}))."\n\n";
	}

	# Channel Items
	my $tcontent = "";
	my $items = $result->{'items'}; # Array reference
	map {
		$tcontent .= $q->Tr(
			$q->td(
				$q->a(
					{ -href => $_->{'link'}},
					$_->{'title'}
				)
			)
		)."\n"
	} (@{$items});
	print $q->table($tcontent)."\n\n";

	# Channel Search Form
	my $textinput = $result->{'textinput'}; # Hash Reference
	if ($textinput->{'link'} ne "")
	{
		print $q->h2($textinput->{'description'})."\n";
		print $q->start_form( {-action => $textinput->{'link'}} )."\n";
		print $q->input( {-name => $textinput->{'name'}} )."\n";
		print $q->input( {-type => "submit",
				-value => $textinput->{'title'} || "Search"})."\n";
		print $q->end_form()."\n\n";
	}
}
__DATA__
http://use.perl.org/useperl.rdf
http://search.cpan.org/recent.rdf
http://www.xml.com/cs/xml/query/q/19
http://www.perlmonks.org/headlines.rdf