first commit

web/src/lib/format.ts

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+/** Time formatting for a screen you look at for three seconds. */
+
+export function relTime(ts: number, now: number): string {
+  const delta = Math.max(0, now - ts);
+  const s = Math.round(delta / 1000);
+  if (s < 5) return "now";
+  if (s < 60) return `${s}s ago`;
+  const m = Math.round(s / 60);
+  if (m < 60) return `${m}m ago`;
+  const h = Math.round(m / 60);
+  if (h < 24) return `${h}h ago`;
+  return `${Math.round(h / 24)}d ago`;
+}
+
+export function clockTime(ts: number): string {
+  return new Date(ts).toLocaleTimeString([], { hour: "2-digit", minute: "2-digit" });
+}
+
+export function duration(ms: number): string {
+  if (ms < 1000) return `${ms}ms`;
+  if (ms < 60_000) return `${(ms / 1000).toFixed(ms < 10_000 ? 1 : 0)}s`;
+  const m = Math.floor(ms / 60_000);
+  const s = Math.round((ms % 60_000) / 1000);
+  return `${m}m ${s}s`;
+}
+
+/** Seconds left, floored at zero, for an approval countdown. */
+export function secondsLeft(expiresAt: number, now: number): number {
+  return Math.max(0, Math.ceil((expiresAt - now) / 1000));
+}