lila/app/controllers/I18n.scala

package controllers

import play.api.data._
import play.api.data.Forms._
import play.api.libs.json.Json

import lila.app._
import lila.common.HTTPRequest

final class I18n(env: Env) extends LilaController(env) {

  private def toLang = lila.i18n.I18nLangPicker.byStr _

  private val form = Form(single("lang" -> text.verifying { code =>
    toLang(code).isDefined
  }))

  def select = OpenBody { implicit ctx =>
    implicit val req = ctx.body
    form.bindFromRequest.fold(
      _ => notFound,
      code => {
        val lang = toLang(code) err "Universe is collapsing"
        ctx.me.filterNot(_.lang contains lang.code).?? { me =>
          env.user.repo.setLang(me.id, lang.code)
        } >> negotiate(
          html = {
            val redir = Redirect {
              HTTPRequest.referer(ctx.req).fold(routes.Lobby.home.url) { str =>
                try {
                  val pageUrl = new java.net.URL(str)
                  val path = pageUrl.getPath
                  val query = pageUrl.getQuery
                  if (query == null) path
                  else path + "?" + query
                } catch {
                  case e: java.net.MalformedURLException => routes.Lobby.home.url
                }
              }
            }
            if (ctx.isAnon) redir.withCookies(env.lilaCookie.session("lang", lang.code))
            else redir
          }.fuccess,
          api = _ => Ok(Json.obj("lang" -> lang.code)).fuccess
        )
      }
    )
  }
}