# frozen_string_literal: true

class Tip < ApplicationRecord
  include Creation

  has_many :exercise_tips
  has_many :exercises, through: :exercise_tips
  belongs_to :file_type, optional: true
  validates :file_type, presence: {if: :example?}
  validate :content?

  def content?
    unless [
      description?, example?
    ].include?(true)
      errors.add :description, :at_least, attribute: Tip.human_attribute_name('example')
    end
  end

  def to_s
    if title?
      "#{Tip.model_name.human}: #{title} (#{id})"
    else
      "#{Tip.model_name.human} #{id}"
    end
  end

  def can_be_destroyed?
    # This tip can only be destroyed if it is no parent to any other exercise tip
    ExerciseTip.where(parent_exercise_tip: exercise_tips).none?
  end
end