fairmondo/fairmondo

#   Copyright (c) 2012-2017, Fairmondo eG.  This file is
#   licensed under the GNU Affero General Public License version 3 or later.
#   See the COPYRIGHT file for details.

module UserConcerns
  module Ratings
    extend ActiveSupport::Concern

    # Update percentage of positive and negative ratings of seller
    # @api public
    # @return [undefined]
    def update_rating_counter
      number_of_ratings = self.ratings.count

      self.update_attributes(percentage_of_positive_ratings: calculate_percentage_of_biased_ratings('positive', 50),
                            percentage_of_neutral_ratings:  calculate_percentage_of_biased_ratings('neutral', 50),
                            percentage_of_negative_ratings: calculate_percentage_of_biased_ratings('negative', 50))

      if (self.is_a?(LegalEntity) && number_of_ratings > 50) || (self.is_a?(PrivateUser) && number_of_ratings > 20)
        if percentage_of_negative_ratings > 50
          self.banned = true
        end
        update_seller_state
      end
    end

    # Calculates percentage of positive and negative ratings of seller
    # @api public
    # @param bias [String] positive or negative
    # @param limit [Integer]
    # @return [Float]
    def calculate_percentage_of_biased_ratings(bias, limit)
      biased_ratings = { 'positive' => 0, 'negative' => 0, 'neutral' => 0 }
      self.ratings.select(:rating).limit(limit).each do |rating|
        biased_ratings[rating.value] += 1
      end
      number_of_considered_ratings = biased_ratings.values.sum
      number_of_biased_ratings = biased_ratings[bias] || 0
      number_of_biased_ratings.fdiv(number_of_considered_ratings) * 100
    end

    def buyer_constants
      {
        not_registered_purchasevolume: 4,
        standard_purchasevolume: 12,
        trusted_bonus: 12,
        good_factor: 2,
        bad_purchasevolume: 6
      }
    end

    def purchase_volume
      purchase_volume = buyer_constants[:standard_purchasevolume]

      purchase_volume *= buyer_constants[:good_factor]        if good_buyer?
      purchase_volume = buyer_constants[:bad_purchasevolume]  if bad_buyer?
      purchase_volume
    end
  end
end