module I18n::Tasks::Configuration
  # i18n-tasks config (defaults + config/i18n-tasks.yml)
  # @return [Hash{String => String,Hash,Array}]
  def config
    @config || (self.config = {})
  end

  def config=(conf)
    @config          = I18n::Tasks.config.deep_merge(conf)
    @config_sections = {}
    @config
  end

  # data config
  #  @return [{adapter: String, options: Hash}]
  def data_config
    @config_sections[:data] ||= begin
      conf    = (config[:data] || {}).with_indifferent_access
      adapter = (conf[:adapter].presence || conf[:class].presence || :file_system).to_s
      if adapter !~ /[A-Z]/
        adapter = "I18n::Tasks::Data::#{adapter.camelize}"
      end
      {adapter: adapter, options: conf.except(:adapter, :class)}
    end
  end

  def relative_roots
    @config_sections[:relative_roots] ||= config[:relative_roots].presence || %w(app/views)
  end

  # translation config
  # @return [Hash{String => String,Hash,Array}]
  def translation_config
    @config_sections[:translation] ||= begin
      conf           = (config[:translation] || {}).with_indifferent_access
      conf[:api_key] ||= ENV['GOOGLE_TRANSLATE_API_KEY'] if ENV.key?('GOOGLE_TRANSLATE_API_KEY')
      conf
    end
  end

  def search_config
    @config_sections[:search] ||= {
        scanner: scanner.class.name,
        config:  scanner.config
    }
  end

  # @return [Array<String>] all available locales, base_locale is always first
  def locales
    @config_sections[:locales] ||= begin
      locales = (config[:locales] || I18n.available_locales).map(&:to_s)
      if locales.include?(base_locale)
        [base_locale] + (locales - [base_locale])
      else
        [base_locale] + locales
      end
    end
  end

  # @return [String] default i18n locale
  def base_locale
    @config_sections[:base_locale] ||= config[:base_locale] || I18n.default_locale.to_s
  end

  # evaluated configuration (as the app sees it)
  def config_sections
    # init all sections
    base_locale
    locales
    data_config
    search_config
    relative_roots
    translation_config
    @config_sections
  end

  def config_for_inspect
    # hide empty sections, stringify keys
    Hash[config_sections.reject { |k, v| v.empty? }.map { |k, v| [k.to_s, v.respond_to?(:stringify_keys) ? v.stringify_keys : v] }]
  end
end