improved Login from response

Signed-off-by: Stephan Richter <s.richter@srsoftware.de>

frontend/src/Components/Login.svelte

@@ -36,7 +36,9 @@
     }
 
 
-    async function redirectTo(service){
+    async function redirectTo(e,service){
+        const btn = e.target;
+        btn.disabled = true;
         const url  = api(`user/oidc/redirect/${service}`);
         const resp = await fetch(url,{credentials:'include'});
         if (resp.ok){
@@ -46,6 +48,9 @@
                 delete json.authorization_endpoint;
                 location.href = endpoint + '?' + new URLSearchParams(json);
             }
+        } else {
+            error = resp.text();
+            btn.disabled = false;
         }
     }
 
@@ -100,6 +105,6 @@
 <fieldset>
     <legend>{t('oidc_Login')}</legend>
     {#each services as service,i}
-    <button onclick={() => redirectTo(service)}>{service}</button>
+    <button onclick={e => redirectTo(e,service)}>{service}</button>
     {/each}
 </fieldset>