module Lolita
  module I18n
    # Allow to operate with I18n keys and values.
    class Backend

      class << self
        # Get translation and decode it. Set translate from and to translations.
        # Return Hash with
        # * <tt>:key</tt> - translation key
        # * <tt>:value</tt> - translation
        # * <tt>:translate_to</tt> - translation locale, like <i>en</i>
        # * <tt>:translate_from</tt> - translation key for default language
        def get(key)
          result={:key=>key}
          result[:value]=decoded_value(key)
          result[:original_value]=decoded_value(translate_from(key))
          result[:translate_to]=translate_to(key)
          result[:translate_from]=translate_from(key)
          result
        end

        # Store translation, decode and store.
        # Accept:
        # * <tt>key</tt> - translation key
        # * <tt>translation</tt> - String with translation
        def set(key,translation)
          locale=translate_to(key)
          translation_key=translation_key(key)
          value=Yajl::Parser.parse(translation.to_json)
          if value.blank?
            del key
          else
            if Lolita.i18n.backend.store_translations(locale,{translation_key=>value},:escape=>false)
              true
            else
              false
            end
          end
        end

        def del key
          Lolita.i18n.store.del key
        end

        def locale(key)
          translate_to(key) || ::I18n.default_locale
        end

        def translation_key(key)
          (key.to_s.split('.')[1..-1]).join(".")
        end
        
        private

        def keys
          @keys||=Lolita.i18n.flattened_translations.keys.sort
        end

        def decoded_value(key)
          value=Lolita.i18n.backend.store[key]
          value ? (Yajl::Parser.parse(value) rescue "") : ::I18n.t(key.split('.')[1..-1].join('.'), :default => "", :locale => translate_to(key))
        end 

        def translate_to(key)
          key.to_s.split(".").first
        end

        def translate_from(key,locale=nil)
          (key.to_s.split('.')[1..-1]).insert(0,locale || ::I18n.default_locale).join(".")
        end

      end

    end
  end
end