Change page locale and translate url

application.html.erb

<ul id="choose_language">
  <% I18n.available_locales.each do |locale| %>
    <li class="<%=locale.to_s%>">
      <a href="http://<%=locale==I18n.default_locale ? 'www' : locale.to_s%>.mydomain.dev/pages/change_locale?url=<%=request.path%>" rel="nofollow"><span>en</span></a>
    </li>
  <% end %>
</ul>

pages_controller.html.rb

class PagesController < ApplicationController
  def change_locale
    path = ActionController::Routing::Routes.recognize_path params[:url]
    redirect_to path
  end
end