#!/usr/bin/perl

use strict;
use warnings;

use HTML::Entities qw(encode_entities);
use XML::Twig;
use URI::Escape;


my @urls;
for(1..150000){
	push(@urls,
		{
			url => "http://www.example.com/some/really/interesting/file.html",
			priority => 0.5,
		}
	);
}

for(1..3){
	my $outfile = "test_sitemap". $_ .".xml";
	print "Working on $outfile, map $_ of 3 (".@urls." remaining URLs)\n";

	## this sitemap
	my $cnt;
	my $sitemap;
	$sitemap = Sitemap->new( type => 'html', file => $outfile );

	# build the xml structure inside out
	foreach my $i (1..49500){
		my $url = shift(@urls);

		last if @urls == 0;

		next if $url->{url} eq '';

		## add
		$sitemap->add({
			loc	 => $url->{url},
			priority => $url->{priority}
		});

		$cnt++;
	}

	my $output = $sitemap->output();
	print " Count: ".($sitemap->{cnt}->{html}||0)." html urls, ".($sitemap->{cnt}->{video}||0)." video urls.\n";
	$sitemap = undef;

	# check length
	if(length($output) < 10485760){
		print " This sitemap file is OK: (uncompressed under 10MB) ". (length($output)) ." bytes\n";
	}else{
		print " This sitemap file is TOO BIG (uncompressed over 10MB).\n";
	}

	open(my $DATEI, ">$outfile") or die "Could not open output file: $!";
	 binmode($DATEI);
	 print $DATEI $output;
	close($DATEI);

	$output = undef;
	print " $cnt URLs added to sitemap $outfile.\n";

	print " Doing gzip compress... ";
	system "gzip -f9 $outfile"; # f forced overwrite, compression level 9/best
	print "done.\n";

	if(-s "$outfile.gz" < 10485760){
		print " This sitemap file is OK (compressed under 10MB) ". (-s "$outfile.gz") ." bytes.\n";
	}else{
		print " This sitemap file is TOO BIG (compressed over 10MB).\n";
	}
}


package Sitemap;

use strict;
use warnings;

use XML::Twig;
use open OUT => ':utf8';
use HTML::Entities qw(encode_entities);
use Data::Dumper;


sub new {
	my ($class, %cfg) = @_;
	my $self = bless {
		xml	=> undef,
		type	=> $cfg{type} || 'html',	# sitemaps are either "video" or "html"
		cnt	=> undef,
	}, $class;

	if($cfg{type} eq 'video'){
		# init XML::Twig for a video-sitemap
		$self->{xml} = XML::Twig::Elt->new('urlset', {
			'xmlns'		=> 'http://www.sitemaps.org/schemas/sitemap/0.9',
			'xmlns:video'	=> 'http://www.google.com/schemas/sitemap-video/1.1',
		});
	}else{
		# init XML::Twig for standard sitemap
		$self->{xml} = XML::Twig::Elt->new('urlset', {
			'xmlns'		=> 'http://www.google.com/schemas/sitemap/0.84',
			'xmlns:xsi'	=> 'http://www.w3.org/2001/XMLSchema-instance',
			'xsi:schemaLocation' => join(' ',
				'http://www.google.com/schemas/sitemap/0.84',
				'http://www.google.com/schemas/sitemap/0.84/sitemap.xsd',
			),
		});
	}

	return $self;
}

sub add {
	my $self = shift;
	my $ref = shift;

	if($self->{type} eq 'video'){
		$self->add_video($ref);
	}else{
		$self->add_html($ref);
	}
}


sub add_html {
	my $self = shift;
	my $ref = shift;

	# step over elements in fixed order
	my @elements;
	foreach my $key (qw(loc changefreq lastmod priority)){
		if($key eq 'loc'){
			if($ref->{loc}){
				push(@elements, XML::Twig::Elt->new('loc', {}, $ref->{loc}) );
			}else{
				print "Error: 'loc' is a mandatory value and missing!\n"
			}
		}elsif($key eq 'priority'){
			if($ref->{priority}){
				push(@elements, XML::Twig::Elt->new('priority', {}, $ref->{priority}) );
			}else{
				print "Error: 'priority' is a mandatory value and missing!\n"
			}
		}
	}

	# wrap these sub-elements into an "url"-level
	my $elt = XML::Twig::Elt->new('url', {}, @elements);
	undef(@elements);

	# and add this url-sub-element nest to the xml-document
	$elt->paste(last_child => $self->{xml});

	$self->{cnt}->{html}++;
}


sub add_video {
	my $self = shift;
	my $ref = shift;

	## omitted
}

sub output {
	my $self = shift;
	my $file = shift;

	$self->{xml}->set_pretty_print('indented');
	my $header = '<?xml version="1.0" encoding="UTF-8"?>'."\n";

	if($file){
		open(my $fh, ">$file") or die "Could not open output file: $!";
		 binmode($fh);
		 print $fh $header . $self->{xml}->sprint();
		close($fh);

		return;
	}else{
		return $header . $self->{xml}->sprint();
	}
}

sub DESTROY {
	my $self = shift;

	undef($self->{xml});
	undef($self);
}

1;