module Middleman::CoreExtensions::ExternalHelpers

def registered(app)
  # Setup a default helpers paths
  app.set :helpers_dir, "helpers"
  app.set :helpers_filename_glob, "**{,/*/**}/*.rb"
  app.set :helpers_filename_to_module_name_proc, Proc.new { |filename|
    basename = File.basename(filename, File.extname(filename))
    basename.camelcase
  }
  # After config
  app.after_configuration do
    helpers_path = File.expand_path(helpers_dir, root)
    next unless File.exists?(helpers_path)
    Dir[File.join(helpers_path, helpers_filename_glob)].each do |filename|
      module_name = helpers_filename_to_module_name_proc.call(filename)
      next unless module_name
      require filename
      next unless Object.const_defined?(module_name.to_sym)
      helpers Object.const_get(module_name.to_sym)
    end
  end
end