module Core
  class Instructor < ActiveRecord::Base
    belongs_to :organisation
    has_many :assignments
    has_many :events, through: :assignments

    validates :name, presence: true

    before_destroy :check_for_events

    default_scope { order('created_at') }

    private

    def check_for_events
      unless events.empty?
        self.errors[:base] << 'Cannot delete Instructors with Events'

        return false
      end
    end
  end
end