#!/usr/bin/perl
use strict;
use warnings;
use LWP;
use URI;
use CGI;

my $query = CGI->new;
my $id = $query->param('id');
my $fmt = $query->param('fmt');
my $fnc = $query->param('callback');

my $ua = LWP::UserAgent->new();
my $req = HTTP::Request->new(GET=> "http://www.youtube.com/get_video_info?video_id=$id" );
my $res = $ua->request( $req );
my @pairs = split(/&/,$res->content);

my ($name, $val);
my %querys;
for ( @pairs ) {
	($name, $val) = split(/=/, $_);
	$querys{ $name } = $val;
}
my $t = $querys{'token'};

my $uri = "";
if ($t)	{
	my $urlText = "http://www.youtube.com/get_video?video_id=$id&t=$t" . ($fmt ? "&fmt=$fmt":"");
	$req = new HTTP::Request POST => $urlText;
	$req->content_type('application/x-www-form-urlencoded');
	$req->content('match=www&errors=0');
	$res = $ua->request($req);
	$uri = URI->new($res->header('Location'));
}

print "Content-type: text/javascript\n\n";
if ($uri)	{
	$req = HTTP::Request->new(HEAD=> $uri );
	$res = $ua->request($req);
	if ($res->content_type =~ /video|mp4|x-flv/i)	{
		print $fnc . '("' . $uri . '");';
		exit;
	}
}
print $fnc . '("");';