Example.rb

class RecountMediamapService
  def initialize(task)
    @task = task
    @comparisons_ids = Film.where.not(kinopoisk_rate: nil).where.not(kinopoisk_rate: 0).where('kinopoisk_num > 10').order(year: :desc, kinopoisk_rate: :desc, kinopoisk_num: :desc).limit(20000).pluck(:id)
    @film = Film.includes(:genres, :subgenres, :countries, :tags, :people).find(@task.task.to_i)
  end

  def recount
    begin
      kbs = {}
      @comparisons_ids.each do |comparison_id|
        comparison = Film.includes(:genres, :subgenres, :countries, :tags, :people).find(comparison_id)
        unless comparison.id == @film.id
          kb = genres_count(comparison) + subgenres_count(comparison) + tags_count(comparison) + countries_count(comparison) + people_count(comparison)
          kbs.update({ comparison.id => kb })
        end
      end
      kbs = kbs.sort {|a,b| b[1]<=>a[1]}
      kbs[0...50].each do |item|
        Likefilm.where(film_id: @film.id, likefilm_id: item[0]).first_or_create(kb: item[1])
      end
      @task.complete
    rescue => e
      @task.error(e)
    end
  end

  protected

  def genres_count(comparison)
    genres_ids = []
    @film.genres.each do |genre|
      genres_ids << genre.id
    end

    like_genres_ids = []
    comparison.genres.each do |genre|
      like_genres_ids << genre.id
    end

    ids = genres_ids & like_genres_ids

    genres_size = ids.size
    if genres_size == 0
      genres_count = 0
    elsif genres_size == 1
      genres_count = 10
    elsif genres_size == 2
      genres_count = 20
    elsif genres_size >= 3
      genres_count = 30
    end
  end

  def subgenres_count(comparison)
    subgenres_ids = []
    @film.subgenres.each do |subgenre|
      subgenres_ids << subgenre.id
    end

    like_subgenres_ids = []
    comparison.subgenres.each do |subgenre|
      like_subgenres_ids << subgenre.id
    end

    if subgenres_ids.size == 0 || like_subgenres_ids.size == 0
      subgenres_count=0
    else
      ids = subgenres_ids & like_subgenres_ids
      subgenres_size = ids.size
      if subgenres_size >= 1
        subgenres_count = 30
      elsif subgenres_size == 0
        subgenres_count = 0
      end
    end
  end

  def tags_count(comparison)
    tags_ids = []
    @film.tags.each do |tag|
      tags_ids << tag.id
    end

    like_tags_ids = []
    comparison.tags.each do |tag|
      like_tags_ids << tag.id
    end

    ids = tags_ids & like_tags_ids
    tags_size = ids.size
    if tags_size == 0
      tags_count = 0
    elsif tags_size == 1
      tags_count = 20
    elsif tags_size == 2
      tags_count = 25
    elsif tags_size >= 3
      tags_count = 30
    end
  end

  def countries_count(comparison)
    countries_ids = []
    @film.countries.each do |country|
      countries_ids << country.id
    end

    like_countries_ids = []
    comparison.countries.each do |country|
      like_countries_ids << country.id
    end

    ids = countries_ids & like_countries_ids
    if ids.size >= 1
      countries_count = 10
    else
      countries_count = 0
    end
  end

  def people_count(comparison)
    directors_ids = []
    writers_ids = []
    actors_ids = []
    @film.films_people.each do |person|
      case person.role
      when 1
        directors_ids << person.person_id
      when 2
        writers_ids << person.person_id
      when 3
        actors_ids << person.person_id
      end
    end

    like_directors_ids = []
    like_writers_ids = []
    like_actors_ids = []
    comparison.films_people.each do |person|
      case person.role
      when 1
        like_directors_ids << person.person_id
      when 2
        like_writers_ids << person.person_id
      when 3
        like_actors_ids << person.person_id
      end
    end

    directors = directors_ids & like_directors_ids
    writers = writers_ids & like_writers_ids
    actors = actors_ids & like_actors_ids

    directors_size = directors.size
    if directors_size == 0
      directors_count = 0
    elsif directors_size >= 1
      directors_count = 20
    end

    writers_size = writers.size
    if writers_size == 0
      writers_count = 0
    elsif writers_size >= 1
      writers_count = 20
    end

    actors_size = actors.size
    if actors_size == 0
      actors_count = 0
    elsif actors_size == 1
      actors_count = 7
    elsif actors_size >= 2
      actors_count = 10
    end

    people_count = directors_count + writers_count + actors_count
  end
end