Fix overwrite of existing cookiejar.

auth.go

@@ -122,18 +122,31 @@ func (kf *KF) TwoFactorAuth(ctx context.Context, resp *http.Response, code uint3
 	return kf.Do(req)
 }
 
-func (kf *KF) RefreshSession(ctx context.Context) error {
+func (kf *KF) IsLoggedIn() bool {
+	return getCookie(kf.client.Jar, kf.domain, "xf_user") != nil
+}
+
+func (kf *KF) RefreshSession(ctx context.Context) (string, error) {
+	const COOKIE_NAME = "xf_session"
+
+	jar := kf.client.Jar
+
 	// Clear any existing session token to request a new one.
-	setCookie(kf.domain, kf.client.Jar, &http.Cookie{
-		Name:  "xf_session",
+	setCookie(jar, kf.domain, &http.Cookie{
+		Name:  COOKIE_NAME,
 		Value: "",
 	})
 
 	resp, err := kf.Get(ctx, kf.domain)
 	if err != nil {
-		return err
+		return "", err
 	}
 	resp.Body.Close()
 
-	return nil
+	session := getCookie(jar, kf.domain, COOKIE_NAME)
+	if session == nil {
+		return "", errors.New("Failed to get new xf_session cookie.")
+	}
+
+	return session.Value, nil
 }