$(function() {

    function capitalize(s){
        return s.replace( /\b./g, function(a){ return a.toUpperCase(); } );
    };

    function generate_user_name() {
        var first_name = $('#registration_first_name').val();
        var last_name = $('#registration_last_name').val();
        var user_name = capitalize(first_name) + capitalize(last_name);
        return user_name.replace( /[\s-]/g, '')
    };

  	// autocomplete of the username (registration form)
    $('#registration_first_name').keyup(function () {
        $('#registration_username').val( generate_user_name() );
    });
    $('#registration_last_name').keyup(function() {
        $('#registration_username').val( generate_user_name() );
    });
});