post '/signup' do
          if is_logged_in?
              redirect to "/users/#{current_user.id}"
          else
            @user = User.new(:username => params['username'], :email => params['email'], :password => params['password'])
            if @user.valid? && @user.present?
                @user.save
                session[:id] = @user.id
                redirect to "/users/#{current_user.id}"
            else
                flash[:message] = @user.errors.messages
                redirect to '/signup'
            end
        end
     end