jQuery Autocomplete with Rails

routes.rb

  get 'users_autocomplete', to: 'users#autocomplete'

user.js

  
jQuery(document).ready(function () {

  jQuery("#selectedTrainerName").text('<%= @user.trained_by.present? ? @user.trained_by.name : 'none' %>');

  function setTrainer(id, label) {
    jQuery('#user_trainer_id').val(id);
    jQuery('#selectedTrainerName').text(label);
  }
  jQuery("#searchTrainerName").autocomplete({
    minLength: 3,
    source: "<%= users_autocomplete_url %>",
    select: function (event, ui) {
      // alert(("You picked '" + ui.item.label + "' with an ID of " + ui.item.id));
      setTrainer(ui.item.id, ui.item.label);
      jQuery(this).autocomplete('close'); 
      this.value = "";
      return false;
    }
  });
});

user.rb

# ...

  def self.search(q)
    lower_q_like = "%#{q.to_s.downcase}%"
    where("lower(users.first_name) LIKE ? OR lower(users.last_name) LIKE ?", lower_q_like, lower_q_like)
  end

  def self.autocomplete_for(term)
    names = self.search(term).compact
    names.map { |p|
      if (names.count(p.name) > 1)
        { label: "#{p.name} (#{p.email})", value: p.name, id: p.id }
      else
        { label: p.name, value: p.name, id: p.id }
      end
    }.sort_by { |p| p[:label] }.compact
  end

users_controller.rb

# ...

  def autocomplete
    render json: User.limit(10).autocomplete_for(params[:term].to_s), status: 200, layout: false
  end