sub get_user_name( $ )
{
   my $data;
   my $query;   

   my $self = shift;

   my $dbh  = $self->{'dbh'};   
    

   my $sqlQuery = "SELECT UserName 
                     FROM USERINFORMATION                     
                    WHERE UserID = \'$self->{user_id}\'";
                        
    $query = $dbh->prepare( $sqlQuery );
      
    $query-> execute() || die $dbh->errstr;

    if( $data = $query->fetchrow_array() )
    {       
        $self->{'error_type'}   = "";   
        $self->{'error_string'} = "";   
        return( $data );
                            
     }
     else
     {
         $self->{'error_type'}   = "variable returned no value";   
         $self->{'error_string'} = "variable returned no value";    
         return( undef ); 
     }  
   
}  





sub update_user_name( $ )
{
   my @data;
   my $query;   

   my $self = shift;

   my $dbh  = $self->{'dbh'};   
    
   # Test for zero length input and 
   if( $_[0] eq "" )
   {
      
      $self->{'error_type'}   = "blank";   
      $self->{'error_string'} = "This variable must be filled in."; 
      return( undef );  
   
   }
    
   # test for input string being too long
   elsif( length( $_[0] ) > 20 )
   {
      
    $self->{'error_type'}   = "overlength";   
      $self->{'error_string'} = "This variable may only be 20 characters."; 
      return( undef );  
   
   } 
    
   # test for chracter correctness
   elsif( $_[0] =~ /[^A-Za-z0-9_]/  )
   {
         
    $self->{'error_type'}   = "illegal characters";   
      $self->{'error_string'} = "Only the chracters A-Z a-z 0-9 _ are allowed.";    
      return( undef );  
   
   }
   
   # test for variable specific cases here

   # username must be unique
   
   
   my $sqlQuery = "SELECT UserID, UserName
                     FROM USERINFORMATION
                    WHERE UserName = \'$_[0]\'";

   my $query = $dbh->prepare( $sqlQuery );

   $query->execute() || die $dbh->errstr;

   @data = $query->fetchrow_array();
   
   #if the userid of the duplicate groupname
   #matches the current userid of the person
   #registering the system then proceed 
   if( $data[0] != $self->{'user_id'} && $data[1] ne "" )  
   { 
   
        $self->{'error_type'}   = "not unique";   
        $self->{'error_string'} = "User Name already in use please choose another.";    
        return( undef );        
   }
   

   else
   {
        my $update = &format_for_mysql( $_[0] );
       
        my $sqlQuery = "UPDATE USERINFORMATION
                          SET UserName = \'$update\'
                          WHERE UserID = $self->{user_id}";
                        
        $query  = $dbh->do( $sqlQuery );
      
         return( 1 );
      
    
    }

}