class TartifletteScoringService
  def self.scored?(tartiflette, session)
    session[:scored_tartiflettes]&.include?(tartiflette.id)
  end

  def self.mark_as_scored(tartiflette, session)
    session[:scored_tartiflettes] ||= []
    unless scored?(tartiflette, session)
      session[:scored_tartiflettes] << tartiflette.id
    end
  end

  def self.submit_scores(tartiflette, scores, session)
    scores.each do |criterium_id, value|
      Score.create!(
        tartiflette: tartiflette,
        scoring_criterium_id: criterium_id,
        value: value[:value]
      )
    end
    mark_as_scored(tartiflette, session)
  end

  def self.average_score(tartiflette)
    tartiflette.scores.average(:value).to_f
  end

  def self.average_score_by_category(tartiflette)
    tartiflette
      .scores
      .group_by { |score| score.scoring_criterium.category }
      .transform_values do |scores|
      (scores.sum(&:value).to_f / scores.size).round(2)
    end
  end

  def self.total_score_by_category(tartiflette)
    tartiflette
      .scores
      .group_by { |score| score.scoring_criterium.category }
      .transform_values do |scores|
      (scores.sum(&:value).to_f / scores.size).round(2)
    end
  end

  def self.leaderboard
    Tartiflette
      .joins(:scores)
      .select("tartiflettes.*, SUM(scores.value) AS total_score")
      .group("tartiflettes.id")
      .order("total_score DESC")
      .map { |tartiflette| [ tartiflette, tartiflette.total_score.to_f ] }
  end
end