class SurveyItem < ActiveRecord::Base
  belongs_to :scale
  has_one :measure, through: :scale

  has_many :survey_item_responses

  def score(school:, academic_year:)
    @score ||= Hash.new do |memo|
      memo[[school, academic_year]] = survey_item_responses.where(school:, academic_year:).average(:likert_score).to_f
    end

    @score[[school, academic_year]]
  end

  scope :student_survey_items, lambda {
    where("survey_item_id LIKE 's-%'")
  }
  scope :teacher_survey_items, lambda {
    where("survey_item_id LIKE 't-%'")
  }
end