disable buttons during long calculation

main.js

@@ -46,6 +46,7 @@ function evaluate() {
 	worker.postMessage({command: "compute", queue, m});
 	timeoutId = setTimeout(() => {
 		document.querySelector("#result").value = "calculating...";
+		switchButtons(false);
 	}, 500);
 }
 
@@ -117,8 +118,9 @@ function switchButtons(enabled) {
 let timeoutId = null;
 const worker = new Worker("./workers/compute.js");
 worker.addEventListener("message", (message) => {
-	document.querySelector("#result").value = message.data;
 	clearTimeout(timeoutId);
+	document.querySelector("#result").value = message.data;
+	switchButtons(true);
 });
 worker.addEventListener("error", (e) => {
 	console.log(e);