URI HTTPS request

OK, I tried the redirect_receiver and got nothing back I understand. Here is my code. Tried this with a simple curl too... 

 let request = NSMutableURLRequest(URL: NSURL(string: "https://www.dropbox.com/oauth2/authorize?client_id=X&response_type=token&redirect_uri=https://www.dropbox.com/1/oauth2/redirect_receiver&state=MTIzNDEyMzQ=")!)

        let session = NSURLSession.sharedSession()

        request.HTTPMethod = "GET"

        let task = session.dataTaskWithRequest(request, completionHandler: {data, response, error -> Void in

            if let error = error {

                completion(string: nil, error: error)

                return

            }

            let strData = NSString(data: data!, encoding: NSUTF8StringEncoding)

            print("getAuth: \(strData)\n\n")

            do {

                let jsonResult = try NSJSONSerialization.JSONObjectWithData(data!, options:NSJSONReadingOptions.MutableContainers);

                completion(string: ", error: nil)

            } catch {

                completion(string: nil, error: error)

            }

        })

        task.resume()

Obviously X here, is my client ID. It returns data, which presumably is parsable if you're running this thru a web browser which as you can see I am not. The guide talks about acting on the authorisation code? which is found where in this 128 lines of text that comes back? I need to run the subsequent http request as I understand the guide? But using the auth code I find under what  in this response?

https://www.example.com/mycallback?code=<authorization code>&state=<CSRF token>

Still lost on the client ID? How does it know the login credentials of the client if all I am giving it is the app ID I setup; I need this to be accessing the local dropbox of the client it is running under.