Use uuid prefix in task table

ui/src/utils.ts

@@ -0,0 +1,61 @@
+interface Duration {
+  hour: number;
+  minute: number;
+  second: number;
+  totalSeconds: number;
+}
+
+// start and end are in milliseconds.
+function durationBetween(start: number, end: number): Duration {
+  const durationInMillisec = start - end;
+  const totalSeconds = Math.floor(durationInMillisec / 1000);
+  const hour = Math.floor(totalSeconds / 3600);
+  const minute = Math.floor((totalSeconds - 3600 * hour) / 60);
+  const second = totalSeconds - 3600 * hour - 60 * minute;
+  return { hour, minute, second, totalSeconds };
+}
+
+function stringifyDuration(d: Duration): string {
+  return (
+    (d.hour !== 0 ? `${d.hour}h` : "") +
+    (d.minute !== 0 ? `${d.minute}m` : "") +
+    `${d.second}s`
+  );
+}
+
+export function durationBefore(timestamp: string): string {
+  try {
+    const duration = durationBetween(Date.parse(timestamp), Date.now());
+    if (duration.totalSeconds < 1) {
+      return "now";
+    }
+    return "in " + stringifyDuration(duration);
+  } catch {
+    return "-";
+  }
+}
+
+export function timeAgo(timestamp: string): string {
+  try {
+    const duration = durationBetween(Date.now(), Date.parse(timestamp));
+    return stringifyDuration(duration) + " ago";
+  } catch {
+    return "-";
+  }
+}
+
+export function getCurrentUTCDate(): string {
+  const today = new Date();
+  const dd = today.getUTCDate().toString().padStart(2, "0");
+  const mm = (today.getMonth() + 1).toString().padStart(2, "0");
+  const yyyy = today.getFullYear();
+  return `${yyyy}-${mm}-${dd}`;
+}
+
+export function uuidPrefix(uuid: string): string {
+  const idx = uuid.indexOf("-");
+  if (idx === -1) {
+    return uuid;
+  }
+  return uuid.substr(0, idx);
+}