Data::Microformat::hFeed - A module to parse and create hFeeds

    use Data::Microformat::hFeed;

    my $feed = Data::Microformat::hFeed->parse($a_web_page);

	print "Feed title is ".$feed->title;
	print "Feed author is ".$feed->author->fullname;	
	foreach my $entry ($feed->entries) {
		print $entry->title."\n";
	}

	# Create a new feed from scratch
	my $feed = Data::Microformat::hFeed->new;
	$feed->id(rand().time().$$);
	$feed->title("A feedtitle");
	$feed->tagline("Some pithy tagline");
	$feed->description("Somebody did something");
	$feed->modified(DateTime->now);
	$feed->copyright({ href => $url, text => 'Some licence' });
	foreach my $category (qw(cat1 cat2 cat3)) {
		$feed->categoriess($tags);
	}
	$feed->author($hcard);
	$feed->entries($entry);

    my $feed = Data::Microformat::hFeed->parse($content);

    my @feeds = Data::Microformat::hFeed->parse($content);

    my $feed = Data::Microformat::hFeed->new;

    my $output = $feed->to_html;

package Data::Microformat::hFeed;

use strict;
use base qw(Data::Microformat);
use Data::Microformat::hFeed::hEntry;
use Data::Microformat::geo;

sub class_name { "hfeed" }
sub singular_fields { qw(id title base language geo link tagline description author modified copyright generator) }
sub plural_fields { qw(entries categories) }

sub from_tree {
 	my $class = shift;
    my $tree  = shift;
	my $url   = shift;

	my @feeds;
	foreach my $feed_tree ($tree->look_down('class', qr/hfeed/)) {
		push @feeds, $class->_convert($feed_tree, $url);
	}
	# As per the spec :
    # "the Feed element is optional and, if missing, is assumed to be the page"
	push @feeds, $class->_convert($tree, $url) unless @feeds;

	return wantarray ? @feeds : $feeds[0];
}

sub generator { shift->SUPER::generator(@_) || __PACKAGE__ }

sub _convert {
	my $class = shift;
	my $tree  = shift;
	my $url   = shift;
	my $feed = $class->new;
	$feed->{_no_dupe_keys} = 1;
	if (defined $url) {
		$feed->link($url);
		$feed->base($url);
	}
	my %tags;
	$tree->look_down(sub {
		my $bit = shift;
		my $feed_class = $bit->attr('class') || $bit->attr('rel') || $bit->attr('lang') || $bit->attr("http-equiv") || $bit->tag || return 0;
		if (!$feed_class) {
			return 0;
		} elsif (_match($feed_class, 'hentry')) {
			$bit->detach;
			$feed->entries(Data::Microformat::hFeed::hEntry->from_tree($bit, $url));
			$bit->delete;
        } elsif (_match($feed_class, 'feed-title')) {
			$feed->title($bit->as_text);
			foreach my $attr (qw(id lang)) {
				$feed->$attr($bit->attr($attr)) if $bit->attr($attr);
			}
        } elsif (_match($feed_class, 'feed-language')) {
			$feed->language($bit->attr('content') || $bit->as_text);
        } elsif (_match($feed_class, 'Content-Language')) {
			$feed->language($bit->attr('content'));
        } elsif (_match($feed_class, 'lang') && $bit->tag eq 'body') {
			$feed->language($bit->attr('lang'));
        } elsif (_match($feed_class, 'self') && $bit->tag eq 'link')  {
			$feed->link($class->_url_decode($bit->attr('href')));
        } elsif (_match($feed_class, 'bookmark'))  {
			$feed->link($class->_url_decode($bit->attr('href')));
        } elsif (_match($feed_class, 'title')) {
			$feed->title($bit->as_text);
        } elsif (_match($feed_class, 'feed-tagline')) {
			$feed->tagline($bit->as_text);
        } elsif (_match($feed_class, 'feed-description')) {
			$feed->description($bit->as_text);
		} elsif (_match($feed_class, 'updated')) {
			$feed->modified(_do_date($bit));
		} elsif (_match($feed_class, 'license')) {
			my $opts = {};
			$opts->{href} = $class->_url_decode($bit->attr('href')) if $bit->attr('href');
			$opts->{text} = $bit->as_text if $bit->as_text;
			$feed->copyright($opts);
		} elsif (_match($feed_class,'vcard')) {
			$bit->detach;
			my $card = Data::Microformat::hCard->from_tree($bit, $url);
			$feed->author($card);
			$bit->delete;
		} elsif (_match($feed_class, 'geo')) {
			$bit->detach;
			my $geo = Data::Microformat::geo->from_tree($bit, $url);
			$feed->geo($geo);
			$bit->delete;
		} elsif (_match($feed_class, 'tag') && _match($feed_class, 'directory')) {
			$feed->categories($bit->as_text);
		} else {
			# print "Unknown class $feed_class\n";
		}
		return 0;
	});
	$feed->{_no_dupe_keys} = 0;
	return $feed;
}

sub _do_date {
	my $element = shift;
	my $title   = $element->attr('title') || return;
	return DateTime::Format::W3CDTF->parse_datetime($title);
}

sub _match {
	my $field  = shift || return 0;
	my $target = shift;
	return $field =~ m!(^|\s)$target(\s|$)!;
}

sub _to_hcard_elements {
	my $feed     = shift;

	my $root  = HTML::Element->new('div', class => 'hfeed');
	$root->attr('id', $feed->id)         if defined $feed->id;
	$root->attr('lang', $feed->language) if defined $feed->language;

	# title
	# link
	if (defined $feed->title) {
		my $title =  HTML::Element->new('div', class => 'feed-title');
		if ($feed->link) {
			my $link = HTML::Element->new('a', href => $feed->link, rel => 'bookmark');
			$link->push_content($feed->title);
			$title->push_content($link);
		} else {
			$title->push_content($feed->title);
		}
		$root->push_content($title);
	}

	# updated
	if ($feed->modified) {
		my $div  = HTML::Element->new('div');
		my $abbr = HTML::Element->new('abbr', class => "updated", title => DateTime::Format::W3CDTF->format_datetime($feed->modified));
		$abbr->push_content($feed->modified->strftime("%B %d, %Y"));
		$div->push_content($abbr);
		$root->push_content($div);
	}

	# tagline
	# description
	foreach my $attr (qw(tagline description)) {
		next unless $feed->$attr;
		my $div = HTML::Element->new('div', class => "feed-$attr");
		$div->push_content($feed->$attr);
		$root->push_content($div);
	}

	# license
	if ($feed->copyright) {
		my $license = $feed->copyright;
		my $div     = HTML::Element->new('div');
		my $a       = HTML::Element->new('a', rel => 'license');
		$a->attr('href', $license->{href})    if defined $license->{href};
		$a->push_content($license->{content}) if  defined $license->{content};
		$div->push_content($a);
		$root->push_content($div);
	}

	# author
	# geo
	foreach my $attr (qw(author geo)) {
		next unless $feed->$attr;
		my $div = HTML::Element->new('div');
		$div->push_content($feed->$attr->_to_hcard_elements);
		$root->push_content($div);
	}

	# categories
	my @categories = $feed->categories;
	if (@categories) {
		my $div = HTML::Element->new('div', class => 'feed-categories');
		$div->push_content("Categories: ");
		foreach my $category (@categories) {
			my $a =  HTML::Element->new('div', rel => 'tag directory');
			$a->push_content($category);
			$div->push_content($a);
		}
		$root->push_content($div);
	}
	
	# entries
	foreach my $entry ($feed->entries) {
		$root->push_content($entry->_to_hcard_elements);
	}
	return $root;
}

1;

__END__

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