weby-lv/weeler

# Weeler I18n backend import helper module.
#
# Loads file translations into datebase.
# Supports: csv, xls, xlsx or ods
#
#   if params[:file].present?
#     I18n::Backend::Weeler::Translation.import params[:file]
#     Setting.i18n_updated_at = Time.now
#   end

begin
  require 'roo'
rescue LoadError => e
  puts "can't use Exporter because: #{e.message}"
end

module I18n
  module Backend
    class Weeler
      module Importer
        extend ActiveSupport::Concern

        module ClassMethods
          # Loads file and iterates each sheet and row.
          def import(file)
            xls = open_spreadsheet(file)

            first_row = xls.first
            locales = locales_from_xlsx_sheet_row(first_row)
            tranlsations_by_locales = Translation.where(locale: locales).group_by(&:locale)

            xls.each_with_index do |row, index|
              next if index.zero?

              store_translations_from_xlsx_row(tranlsations_by_locales, row, locales)
            end
          end

          private

          # Open csv, xls, xlsx or ods file and read content
          def open_spreadsheet(file)
            case File.extname(file.original_filename)
            when ".csv"  then Roo::CSV.new(file.path, file_warning: :ignore)
            when ".xls"  then Roo::Excel.new(file.path, file_warning: :ignore)
            when ".xlsx" then Roo::Excelx.new(file.path, file_warning: :ignore)
            when ".ods"  then Roo::OpenOffice.new(file.path, file_warning: :ignore)
            else raise "Unknown file type: #{file.original_filename}"
            end
          end

          # Lookup locales and sequence for loading
          def locales_from_xlsx_sheet_row(row)
            locales = []
            row.each_with_index do |cell, i|
              next unless i.positive?

              locale = cell.downcase

              # check if legal local
              next if locale.size != 2

              locales.push(cell.downcase)
            end
            locales
          end

          # Iterate each cell in row and store translation by locale
          def store_translations_from_xlsx_row(tranlsations_by_locales, row, locales)
            locale = nil
            key = nil

            row.each_with_index do |cell, i|
              if i.zero?
                key = cell
              else
                locale = locales[i - 1]

                store_translation_from_xlsx_cell(tranlsations_by_locales[locale.to_s], locale, key, cell) if locale.present?
              end
            end
          end

          # Store locale if locale and key present
          def store_translation_from_xlsx_cell(locale_translations, locale, key, cell)
            value = cell.nil? ? '' : cell

            return if locale.blank? || key.blank?

            translation = locale_translations&.find { |t| t.key == key }

            return if translation.present? && translation.value == value

            translation ||= Translation.new(locale: locale, key: key)
            translation.value = value
            translation.save
          end
        end
      end

      Translation.send(:include, Importer)
    end
  end
end