def request_token
  fb = FreshbooksOauth.new(current_user.fb_url)
  @request_token = fb.get_request_token(fb_callback_url)
  session[:fb_request_token] = @request_token.token 
  session[:fb_request_token_secret] = @request_token.secret
  redirect_to @request_token.authorize_url    
end

def callback
  fb = FreshbooksOauth.new(current_user.fb_url)
  @access_token = fb.exchange_request_for_access_token(
          session[:fb_request_token], 
          session[:fb_request_token_secret], 
          params[:oauth_verifier])
  current_user.update_attributes(:fb_token=>@access_token.token.to_s, 
          :fb_secret=>@access_token.secret.to_s)
  redirect_to fb_show_path
end

def show
  if((current_user.fb_token.blank? || current_user.fb_secret.blank?) && session[:fb_error].blank?) 
    session[:fb_error] = true
    redirect_to fb_request_token_path 
    return
  end
 
  client = FreshBooks::Client.new(current_user.fb_url+'.freshbooks.com', 
          'YOUR FRESHBOOKS SUBDOMAIN HERE (i.e. clockwork)',
          'OAUTH SECRET HERE', 
          current_user.fb_token, 
          current_user.fb_secret)
  @invoices = client.invoice.list :status => 'unpaid'

  #If returns error
  if(@invoices['error'])
    #If first error, get new request token and try again
    if session[:fb_error].blank?
       session[:fb_error] = true
       redirect_to fb_request_token_path
    else
      session[:fb_error] = nil
      redirect_to freshbooks_path, 
              :notice => 'There was an authentication error'
    end
  end
end