improve type guards

src/lib/helper/seconds-to-timestamp.ts

@@ -0,0 +1,18 @@
+function section(t: number) {
+	if (t < 10) return `0${t}`;
+	return t;
+}
+
+export function secondsToTimestamp(seconds: number) {
+	const hh = Math.floor(seconds / 3600);
+	const hh_remainder = seconds % 3600;
+	const mm = Math.floor(hh_remainder / 60);
+	const mm_remainder = hh_remainder % 60;
+	const ss = Math.floor(mm_remainder);
+
+	const hrs = hh > 0 ? `${section(hh)}:` : '';
+	const mins = mm ? `${section(mm)}:` : '00:';
+	const secs = ss ? `${section(ss)}` : '00';
+
+	return `${hrs}${mins}${secs}`;
+}