Returns the first segment past known TlDs

CleanHostHeaders.cs

/// <summary>
/// Returns the first segment past known TLDs
/// </summary>
/// <param name="uri">Source Uri</param>
/// <param name="tlds">http://data.iana.org/TLD/tlds-alpha-by-domain.txt</param>
/// <returns>Target Uri</returns>
private static Uri CleanHostHeaders(Uri uri, IEnumerable<string> tlds)
{
    // IANA currently has the list upper case
    string host = uri.Host.ToUpper();
    var hostSegments = host.Split('.');

    var matchedSegments = new List<string>();
    for (int i = hostSegments.Length; i >= 1; i--)
    {
        string segment = hostSegments[i - 1];
        if (tlds.Any(x => x.Contains(segment)))
            matchedSegments.Add(segment);
        else
        {
            // There wasn't a match so mean it could be the 
            //  domain name if we've found any tld match
            if (matchedSegments.Any())
            {
                matchedSegments.Add(hostSegments[i - 1]);
                break;
            }
        }
    }

    matchedSegments.Reverse();
    return new Uri(string.Concat(uri.Scheme, Uri.SchemeDelimiter, string.Join(".", matchedSegments)));
}