module VulgataCallbacks
  extend ActiveSupport::Concern

  included do
    if Vulgata::Helpers.vulgata_table_exists?
      after_create :init_vulgata_states, unless: :vlg_skip_init
      after_update :pendify_translation_states
      after_destroy :destroy_translation_states
    else
      logger.warn("WARNING: 'vulgata_translation_states' doesn't exist, vulgata will not create translation states. Please create the table using vulgata's migration and then run the init script again.")
    end
  end

  def init_vulgata_states(reload = true)
    
    source_translation, translated_item_id = vulgata_source_and_translated_item_id

    # no source no states - translators cant translate without source
    return if source_translation.nil?

    source_attributes = {
      item_type: self.vulgata_item_type,
      item_id: translated_item_id,
      status: Vulgata::TranslationState.statuses[:source],
      locale: source_translation.locale
    }

    Vulgata::TranslationState.find_or_create_by(source_attributes) do |state|
      state.created_at = source_translation.created_at
      state.updated_at = source_translation.updated_at
    end

    not_source_locales = Vulgata::Helpers.available_locales - [source_translation.locale.to_sym]

    not_source_locales.each do |locale|
      state = Vulgata::TranslationState.find_or_initialize_by(item_type: self.vulgata_item_type, item_id: translated_item_id, locale: locale)
      state.priority = self.vulgata_priority
      translation = vlg_strategy.translation_data_with_meta state
      if translation.present?
        state.status = Vulgata::TranslationState.statuses[:approved]
        state.comment = "Initial"
        state.created_at = translation.created_at
        state.updated_at = translation.updated_at
      else
        state.status = Vulgata::TranslationState.statuses[:pending]
        state.comment = "Initial"
        state.created_at = source_translation.created_at
        state.updated_at = source_translation.updated_at
      end
      state.save
    end

    self.reload if reload
  end

  def pendify_translation_states
    # after translation is created we should skip the update
    if self.vlg_skip_pendify
      self.vlg_skip_pendify = nil
      return true
    end

    # check if the update includes the attributes being translated
    return unless vlg_strategy.translation_data_changed? self

    source_translation, translated_item_id = vulgata_source_and_translated_item_id

    # no source no states - translators cant translate without source
    return if source_translation.nil?

    not_source_locales = Vulgata::Helpers.available_locales - [source_translation.locale.to_sym]

    # update all translations to pending
    not_source_locales.each do |locale|
      state = Vulgata::TranslationState.where(item_type: self.vulgata_item_type, item_id: translated_item_id, locale: locale).first_or_initialize
      state.status = :pending
      state.user = nil
      state.priority = self.vulgata_priority
      state.save
    end
  end

  def destroy_translation_states
    Vulgata::TranslationState.destroy_all(item_type: self.vulgata_item_type, item_id: self.id)
  end

  private

  def vulgata_source_and_translated_item_id
    source_translation = self.vlg_strategy.source_translation(self)

    # some translation strategies use the same table with locale column and some have another translation table
    # we should handle both situations to find the coresponding id by checking the class of the translation
    translating_item_id = source_translation.class == self.class ? source_translation.id : self.id
    return source_translation, translating_item_id
  end
end