In order to try and keep the generated tweets below the 140 char limit I have made some modifications to the prepareMessage function.

The general gist of the code is:

• if generated message is <140 then carry on as normal
• if the message with a full URL is <120 characters then we will truncate the title and append "..."
• If that is still too long then sue a short URL using the node id

(this code assumes directory URL's - a small modification is required if not used.)

            if (template.Replace("#title#", title).Replace("#url#", url).Length < 140)
            {
                template = template.Replace("#title#", title).Replace("#url#", url);
            }
            else if (template.Replace("#url#", url).Length < 120)
            {
                //allow full URL & truncated title - less than 120 to leave enough space for meaningful title
                template = template.Replace("#url#", url).Replace("#title#", title.Substring(0, 135 - template.Replace("#url#", url).Length) + "...");
            }
            else
            {
                // otherwise url will be http:example.com/1234  (assumes directory URL's)
                Uri u = HttpContext.Current.Request.Url;
                String baseUrl = u.Scheme + "://" + u.Host + "/";
                template = template.Replace("#url#", baseUrl + d.Id.ToString()).Replace("#title#", title.Substring(0, 135 - template.Replace("#url#", url).Length) + "...");
            }