notification.rb

# frozen_string_literal: true

class Notification < ApplicationRecord
  TARGETS_TO_KINDS = {
    announcement: [:announced],
    mention: [:mentioned],
    comment: %i[came_comment answered],
    check: %i[checked assigned_as_checker product_update],
    watching: [:watching],
    following_report: [:following_report]
  }.freeze

  belongs_to :user
  belongs_to :sender, class_name: 'User'

  paginates_per 20

  enum kind: {
    came_comment: 0,
    checked: 1,
    mentioned: 2,
    submitted: 3,
    answered: 4,
    announced: 5,
    came_question: 6,
    first_report: 7,
    watching: 8,
    retired: 9,
    trainee_report: 10,
    moved_up_event_waiting_user: 11,
    create_pages: 12,
    following_report: 13,
    chose_correct_answer: 14,
    consecutive_sad_report: 15,
    assigned_as_checker: 16,
    product_update: 17,
    graduated: 18,
    hibernated: 19,
    signed_up: 20,
    regular_event_updated: 21,
    no_correct_answer: 22,
    comebacked: 23,
    create_article: 24,
    added_work: 25,
    came_inquiry: 26
  }

  scope :unreads, -> { where(read: false) }
  scope :with_avatar, -> { preload(sender: { avatar_attachment: :blob }) }
  scope :by_read_status, ->(status) { status == 'unread' ? unreads.with_avatar : with_avatar }

  scope :by_target, lambda { |target|
    target ? where(kind: TARGETS_TO_KINDS[target]) : all
  }

  scope :latest_of_each_link, lambda {
    select('DISTINCT ON (link) *').order(link: :asc, created_at: :desc, id: :desc) # 「作成日時が最新の通知」が複数ある場合に取得する1件の通知を一定にするため、ORDER BY の最後に id の降順を指定した
  }

  after_create NotificationCallbacks.new
  after_update NotificationCallbacks.new
  after_destroy NotificationCallbacks.new

  def unread?
    !read
  end

  def unique?(scope: [])
    !other_duplicates(scope:).exists?
  end

  private

  def other_duplicates(scope: [])
    duplicates = scope.inject(Notification.all) { |notifications, scope_item| notifications.where(scope_item => self[scope_item]) }
    duplicates.where.not(id:)
  end
end