class MakeTrackedTimeEntryPolymorphic < ActiveRecord::Migration[7.1]
  def change
    add_reference :tracked_time_entries, :subject, polymorphic: true

    reversible do |dir|
      dir.up do
        TrackedTimeEntry.all.each do |entry|
          entry.update!(subject: Lecture.find(entry.lecture_id))
        end
      end

      dir.down do
        TrackedTimeEntry.all.each do |entry|
          entry.update!(lecture_id: entry.subject_id)
        end
      end
    end
  end
end