# frozen_string_literal: true

# == Schema Information
#
# Table name: poll_votes
#
#  id             :integer          not null, primary key
#  rank           :integer
#  created_at     :datetime         not null
#  poll_option_id :integer          not null
#  user_id        :integer          not null
#
# Indexes
#
#  index_poll_votes_on_poll_option_id_and_user_id  (poll_option_id,user_id) UNIQUE
#  index_poll_votes_on_user_id                     (user_id)
#
# Foreign Keys
#
#  fk_rails_...  (poll_option_id => poll_options.id) ON DELETE => cascade ON UPDATE => cascade
#  fk_rails_...  (user_id => users.id) ON DELETE => cascade ON UPDATE => cascade
#
class PollVote < ApplicationRecord
  belongs_to :user, optional: true
  belongs_to :option, class_name: 'PollOption', foreign_key: 'poll_option_id', inverse_of: :votes, optional: true
  has_one :poll, through: :option, foreign_key: 'poll_id'
  has_one :topic, through: :option

  # Make sure a user can only vote on the same option once
  validates :poll_option_id, uniqueness: { scope: :user_id }

  after_create :increase_counters
  after_destroy :decrease_counters

  def increase_counters
    option.increment! :vote_count
    poll.increment! :total_votes
  end

  def decrease_counters
    option.decrement! :vote_count
    poll.decrement! :total_votes
  end
end