gistfile1.js

/**
 * InviteWindow
 */

YUI().use('node', 'value-change', 'substitute', 'form-overlabels', 'resource', function(Y){
    
    Y.on('domready', function(){
        
        var inviteForm          = Y.one('#invite').plug(Y.Plugin.FormOverlabels),
            inviteFormInput     = inviteForm.one('input'),
            inviteFormControl   = inviteForm.one('button'),
            inviteFormMessage   = inviteForm.one('#invite-message'),
            inviteResource      = new Y.Resource({ uri: inviteForm.get('action') }),
            messageTemplate     = '<p>Hmmm… <strong>{code}</strong> seems to be an invalid or already used invite code. ' +
                                  'Let us know if this seems wrong: ' +
                                  '<strong><a href="mailto:support@">support@</a></strong></p>';
        
        inviteFormControl.set('disabled', inviteFormInput.get('value').length === 0);
        
        inviteFormInput.on('valueChange', function(e){
            inviteFormControl.set('disabled', e.newVal.length === 0);
            inviteFormMessage.setContent(null);
        });
        
        inviteForm.on('submit', function(e){
            
            e.preventDefault();
            
            inviteResource.POST({
                
                params  : { code: inviteFormInput.get('value') },
                on      : {
                    
                    success : function(e){
                        window.location.reload(true);
                    },
                    
                    failure : function(e){
                        inviteFormMessage.setContent(Y.substitute(messageTemplate, e.request.params));
                    }
                    
                }
                
            });
            
        });

    });
    
});