Editing Add a parallel authentication routine (section)

=== changing the way the puid is displayed, and selected ===
As defined earlier, the puid is a text field in the user object, and will contain a puid in the form of ''1234:5678#My+department''.
Standard eprints functionality for a text field is to display the contents in an input field, and allow the user to edit it. This is no use to us, as we want the user to select between one of three options:
* None
* Current: Dept 1
* New: Dept 2
(depending, of course, on what is currently set and whether there is a mis-match between <code>user->puid</code> and the puid from ''myCookie'')

We can alter the way the object deals with a field using local functions. In <code>archives/''ARCHIVEID''/cfg/cfg.d/user_fields.pl</code>, we add references to the functions for rendering the field  and for changing the value. These two methods return DOM fragments of XML:
<pre>
    {
        'name'                => 'puid',
        'type'                => 'text',
        'render_single_value' => \&render_puid,
        'render_input'        => \&select_puid,
    },
</pre>
In <code>archives/''ARCHIVEID''/cfg/cfg.d/user_fields.pl</code> we also add the two methods:
<pre>
sub render_puid
{
    my ( $session, $field, $value ) = @_;

     	if(!EPrints::Utils::is_set($value)) 
	{
		return $session->make_text("You have no automatic authentication");
	}

	# split the value into two parts, on the first # (there may be more than one..)
	my ( $rawpuid, $inst) = split /#/, $value, 2; 
	$inst =~ s/\+/ /g;

	if( !EPrints::Utils::is_set($inst) )
	{
        	return $session->make_text(
            		"You have an institution defined, but it is un-named");
	}

        $inst =~ s/\+/ /g;
        # we should have an institutionl name set, but just in case...
        return $session->make_text(
            "Your defined authenticating institution is $inst")

 
}

sub select_puid {
    my ( $field, $session, $puid, $dataset, $staff, $hidden_fields, $user,
        $basename ) = @_;
   my @order = ('none');
   my $desc = { none => 'No PUID stuff' };
   my $values = { 'none' => '' };

   my $default = 'none';

   if( EPrints::Utils::is_set( $value ) )
   {
     push @order, 'old';
     $values->{old} = $value;
     my ($uid, $org) = split /\#/, $value;
     $org =~ s/\+/ /g;
     $desc->{old} = "Current value: $org";
     $default = 'old';
   }

   my $cookie_puid = $session->puid_from_cookie;
   if( defined $cookie_puid && $cookie_puid ne $value )
   {
     push @order, 'new';
     $values->{new} = $cookie_puid;
     my ($uid, $org) = split /\#/, $cookie_puid;
     $org =~ s/\+/ /g;
     $desc->{new} = "New value: $org";
   }

   my $div = $session->make_element( "div" );
   foreach my $bit ( @order ) 
   {
      my $div2 = $session->make_element( "div" );
      my $label = $session->make_element( "label" );
      $div->appendChild( $div2 );
      $div2->appendChild( $label );
      my %iopts = (
                type=>'radio',
                name=>$basename,
                value=>$values->{$bit} );
      if( $default eq $bit ) { $iopts{checked} = 'checked'; }
      $label->appendChild( $session->make_element( "input", %iopts ) );
      $label->appendChild( $session->make_text( " ".$desc->{$bit} ) );
   }
     
   return $div;

 
}
</pre>