sub content_type      {
    my $self = shift;
    my $ct = $self->{'content-type'};
    $self->{'content-type'} = shift if @_;
    $ct = $ct->[0] if ref($ct) eq 'ARRAY';
    return '' unless defined($ct) && length($ct);
    my @ct = split(/;\s*/, $ct, 2);
    for ($ct[0]) {
	s/\s+//g;
	$_ = lc($_);
    }
    wantarray ? @ct : $ct[0];
}

sub content_is_html {
    my $self = shift;
    return $self->content_type eq 'text/html' || $self->content_is_xhtml;
}

sub content_is_xhtml {
    my $ct = shift->content_type;
    return $ct eq "application/xhtml+xml" ||
           $ct eq "application/vnd.wap.xhtml+xml";
}

sub content_is_xml {
    my $ct = shift->content_type;
    return 1 if $ct eq "text/xml";
    return 1 if $ct eq "application/xml";
    return 1 if $ct =~ /\+xml$/;
    return 0;
}

sub referer           {
    my $self = shift;
    if (@_ && $_[0] =~ /#/) {
	# Strip fragment per RFC 2616, section 14.36.
	my $uri = shift;
	if (ref($uri)) {
	    $uri = $uri->clone;
	    $uri->fragment(undef);
	}
	else {
	    $uri =~ s/\#.*//;
	}
	unshift @_, $uri;
    }
    ($self->_header('Referer', @_))[0];
}
*referrer = \&referer;  # on tchrist's request

sub title             { (shift->_header('Title',            @_))[0] }
sub content_encoding  { (shift->_header('Content-Encoding', @_))[0] }
sub content_language  { (shift->_header('Content-Language', @_))[0] }
sub content_length    { (shift->_header('Content-Length',   @_))[0] }

sub user_agent        { (shift->_header('User-Agent',       @_))[0] }
sub server            { (shift->_header('Server',           @_))[0] }

sub from              { (shift->_header('From',             @_))[0] }
sub warning           { (shift->_header('Warning',          @_))[0] }

sub www_authenticate  { (shift->_header('WWW-Authenticate', @_))[0] }
sub authorization     { (shift->_header('Authorization',    @_))[0] }

sub proxy_authenticate  { (shift->_header('Proxy-Authenticate',  @_))[0] }
sub proxy_authorization { (shift->_header('Proxy-Authorization', @_))[0] }

sub authorization_basic       { shift->_basic_auth("Authorization",       @_) }
sub proxy_authorization_basic { shift->_basic_auth("Proxy-Authorization", @_) }

sub _basic_auth {
    require MIME::Base64;
    my($self, $h, $user, $passwd) = @_;
    my($old) = $self->_header($h);
    if (defined $user) {
	Carp::croak("Basic authorization user name can't contain ':'")
	  if $user =~ /:/;
	$passwd = '' unless defined $passwd;
	$self->_header($h => 'Basic ' .
                             MIME::Base64::encode("$user:$passwd", ''));
    }
    if (defined $old && $old =~ s/^\s*Basic\s+//) {
	my $val = MIME::Base64::decode($old);
	return $val unless wantarray;
	return split(/:/, $val, 2);
    }
    return;
}


1;

__END__

=head1 NAME

HTTP::Headers - Class encapsulating HTTP Message headers