Code for creating pool objects for the future

pool creation.rb

class PoolsCreator

  def create_all
    Week.where("starting_on > ?", 1.week.ago).each do |week|
      create_for_week(week)
    end
  end

  def create_for_week(week)
    City.active.each do |city|
      datetimes_for_city(week, city).each do |datetime|
        next if pool_exists?(city, datetime) 
        p "creating pool #{city.name} #{week.id} #{datetime}"
        Pool.create!(
          datetime: datetime,
          city_id: city.id,
          week_id: week.id,
        )
      end
    end
  end

  def pool_exists?(city, datetime)
    Pool.where(city_id: city.id)
      .where("datetime > ?", datetime - 12.hours)
      .where("datetime < ?", datetime + 12.hours)
      .exists?
  end

  def datetimes_for_city(week, city)
    (0..4).map do |day|
      date = week.starting_on + day.days
      dt = date.strftime("%Y-%m-%d 20:00:00")
      ActiveSupport::TimeZone[city.time_zone].parse(dt)
    end
  end
end