Refine device inventory layout and last-seen details

src/web/utils/format.js

@@ -29,3 +29,38 @@ export function formatTime(iso) {
   if (!iso) return "";
   return new Date(iso).toLocaleTimeString("ru-RU", { hour12: false });
 }
+
+export function formatLastSeen(iso, now = new Date()) {
+  const date = new Date(iso);
+  if (Number.isNaN(date.getTime())) return { label: "Нет данных", tooltip: "Нет данных" };
+  const current = new Date(now);
+  const day = (value) => Date.UTC(value.getFullYear(), value.getMonth(), value.getDate());
+  const daysAgo = Math.round((day(current) - day(date)) / 86_400_000);
+  const time = date.toLocaleTimeString("ru-RU", { hour: "2-digit", minute: "2-digit" });
+  const dateLabel = daysAgo === 0
+    ? "Сегодня"
+    : daysAgo === 1
+      ? "Вчера"
+      : date.toLocaleDateString("ru-RU", {
+          day: "numeric",
+          month: "long",
+          ...(date.getFullYear() === current.getFullYear() ? {} : { year: "numeric" }),
+        });
+  const elapsedMs = Math.max(0, current.getTime() - date.getTime());
+  const units = elapsedMs < 60 * 60 * 1000
+    ? [Math.max(1, Math.floor(elapsedMs / 60_000)), "minute"]
+    : elapsedMs < 24 * 60 * 60 * 1000
+      ? [Math.floor(elapsedMs / 3_600_000), "hour"]
+      : [Math.floor(elapsedMs / 86_400_000), "day"];
+  const relative = elapsedMs < 60_000
+    ? "только что"
+    : new Intl.RelativeTimeFormat("ru-RU", { numeric: "always" }).format(-units[0], units[1]);
+  const full = date.toLocaleString("ru-RU", {
+    day: "numeric",
+    month: "long",
+    year: "numeric",
+    hour: "2-digit",
+    minute: "2-digit",
+  });
+  return { label: `${dateLabel}, ${time}`, tooltip: `${full} (${relative})` };
+}