Umbraco : on root node, redirect to current users browser culture ex: /en/ or /fr/

RedirectToLanguage.cshtml

@using System.Globalization
@inherits Umbraco.Web.Mvc.UmbracoTemplatePage
@{
    Layout = null;

    string[] languages = HttpContext.Current.Request.UserLanguages;
    var detectedLanguage = false;
    var urlToRedirect = "/en/";  // TODO : go to first node homepage?

	HttpCookie cookieOptIn = Request.Cookies.Get("curLang");
	
	@* If it's the first time a user goes to this website and there's no cookie yet *@
	if(cookieOptIn == null) 
	{
		if (languages != null && languages.Any())
		{
			var allHomapeges = Model.Content.Descendants("Homepage");
	
			if (allHomapeges != null && allHomapeges.Any())
			{
				foreach (var lang in languages)
				{
					if (detectedLanguage)
					{
						break;
					}
	
					var letfLanguageTag = CultureInfo.GetCultureInfoByIetfLanguageTag(lang.Split(';')[0]).IetfLanguageTag;
	
					<div>@lang » @letfLanguageTag</div>
	
					foreach (var homepage in allHomapeges)
					{
						if (homepage.Name.Equals(letfLanguageTag, StringComparison.InvariantCultureIgnoreCase))
						{
							urlToRedirect = homepage.Url;
							
							cookieOptIn = new HttpCookie("curLang");
							cookieOptIn.Value = urlToRedirect;
							cookieOptIn.Expires = DateTime.Now.AddDays(30);
							Response.Cookies.Add(cookieOptIn);
							
							detectedLanguage = true;
							break;
						}
	
						if (detectedLanguage)
						{
							break;
						}
					}
				}
			}
		}
	}
	else
	{
		var urlPPath = cookieOptIn.Value;
		urlToRedirect = urlPPath;
	}
	
	Response.RedirectPermanent(urlToRedirect);  // DONT END RESPONSE; RedirectPermanent = 301
}

// TODO: if user change website language on language menu selector, UPDATE cookie