locales_update.rake

require 'ya2yaml' # Better than to_yaml, because it saves as UTF-8 and sorts hash by keys

namespace :locales do
  desc "Parses ActiveRecord models and updates locale files"
  task :update => :environment do
    Dir.glob(File.join(RAILS_ROOT, 'config', 'locales', '*.yml') ).each do |locale_file|
      # Read single locale file
      locale_hash = YAML.load(File.read(locale_file))
      language = locale_hash.keys.first
    
      # Find all ActiveRecord models
      all_models = Dir.glob(File.join(RAILS_ROOT, 'app', 'models', '*.rb')).map { |path| path[/.+\/(.+).rb/,1] }
      ar_models = all_models.select { |model| model.camelize.constantize < ActiveRecord::Base  }.collect { |model| model.camelize.constantize }
      
      ar_models.each do |model|
        # Model.human_name
        locale_hash[language]['activerecord']['models'][model.name.underscore] = model.human_name
        
        # Model.human_attribute_name
        model.column_names.each do |column_name|
          unless column_name.match /(_id\z|\Aid\z|_type\z)/
            (locale_hash[language]['activerecord']['attributes'][model.name.underscore] ||= {})[column_name] = model.human_attribute_name(column_name)
          end
        end
      end
    
      # Write updated locale file
      File.open(locale_file, 'w') do |file|
        file.write(locale_hash.ya2yaml)
      end
    end
  end
end