unify Shanghai time across Semi UI workspaces

vehicle-data-platform/apps/web/src/v2/domain/formatters.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, it } from 'vitest';
-import { formatZhNumber } from './formatters';
+import { formatShanghaiDateTime, formatZhNumber } from './formatters';
 
 describe('formatZhNumber', () => {
   it('formats Chinese locale numbers with independent precision caches', () => {
@@ -13,3 +13,17 @@ describe('formatZhNumber', () => {
     expect(formatZhNumber(Number.NaN, 2)).toBe('NaN');
   });
 });
+
+describe('formatShanghaiDateTime', () => {
+  it('renders explicit timestamps in Shanghai and preserves local business values', () => {
+    expect(formatShanghaiDateTime('2026-07-18T02:33:00Z')).toBe('2026-07-18 10:33:00');
+    expect(formatShanghaiDateTime('2026-07-18T02:33:00+08:00')).toBe('2026-07-18 02:33:00');
+    expect(formatShanghaiDateTime('2026-07-18 02:33:00')).toBe('2026-07-18 02:33:00');
+  });
+
+  it('converts timezone-less UTC service timestamps only when the source contract says UTC', () => {
+    expect(formatShanghaiDateTime('2026-07-18 02:33:00', { sourceZone: 'utc' })).toBe('2026-07-18 10:33:00');
+    expect(formatShanghaiDateTime('', { sourceZone: 'utc' })).toBe('—');
+    expect(formatShanghaiDateTime(undefined, { empty: '尚未上报' })).toBe('尚未上报');
+  });
+});

vehicle-data-platform/apps/web/src/v2/domain/formatters.ts

@@ -1,4 +1,16 @@
 const zhNumberFormatters = new Map<number, Intl.NumberFormat>();
+const shanghaiDateTimeFormatter = new Intl.DateTimeFormat('sv-SE', {
+  timeZone: 'Asia/Shanghai',
+  year: 'numeric',
+  month: '2-digit',
+  day: '2-digit',
+  hour: '2-digit',
+  minute: '2-digit',
+  second: '2-digit',
+  hour12: false
+});
+
+export type DateTimeSourceZone = 'preserve' | 'utc';
 
 export function formatZhNumber(value: number, maximumFractionDigits = 0) {
   let formatter = zhNumberFormatters.get(maximumFractionDigits);
@@ -8,3 +20,18 @@ export function formatZhNumber(value: number, maximumFractionDigits = 0) {
   }
   return formatter.format(value);
 }
+
+export function formatShanghaiDateTime(
+  value?: string,
+  { empty = '—', sourceZone = 'preserve' }: { empty?: string; sourceZone?: DateTimeSourceZone } = {}
+) {
+  if (!value?.trim()) return empty;
+  const source = value.trim();
+  const fallback = source.replace('T', ' ').replace(/\.\d{1,9}/, '').replace(/Z$/, '').slice(0, 19);
+  const hasExplicitZone = /(?:Z|[+-]\d{2}:?\d{2})$/i.test(source);
+  if (!hasExplicitZone && sourceZone === 'preserve') return fallback;
+  const normalized = hasExplicitZone ? source : `${source.replace(' ', 'T')}Z`;
+  const parsed = new Date(normalized);
+  if (!Number.isFinite(parsed.getTime())) return fallback || empty;
+  return shanghaiDateTimeFormatter.format(parsed).replace('T', ' ');
+}