add overnight desk handling and effective window configuration for train schedules

apps/edr-freight-api/src/modules/train-scheduling/batch-window.util.spec.ts

@@ -119,6 +119,34 @@ describe('computeImportWindowTimes — first-window open respects office hours',
     );
     expect(windowClosesAt.toISOString()).toBe(departure.toISOString());
   });
+
+  describe('overnight desk (open > close, wraps past midnight)', () => {
+    // Desk open 08:00, closes 05:00 next morning — open across midnight.
+    const overnight = { ...bounded, windowOpenHour: 8, windowCloseHour: 5 };
+
+    it('opens NOW at 00:00 (deep night is INSIDE the overnight window)', () => {
+      // Now = 05 Jul 00:00 EAT (04 Jul 21:00 UTC): after midnight, before 05:00 →
+      // inside the overnight desk → open immediately. This is the reported bug.
+      const now = new Date('2026-07-04T21:00:00.000Z');
+      const { windowOpensAt } = computeImportWindowTimes(departure, overnight, now);
+      expect(windowOpensAt.toISOString()).toBe('2026-07-04T21:00:00.000Z');
+    });
+
+    it('opens NOW at 22:00 (evening is INSIDE the overnight window)', () => {
+      // Now = 05 Jul 22:00 EAT (19:00 UTC): after 08:00 open → inside → open now.
+      const now = new Date('2026-07-05T19:00:00.000Z');
+      const { windowOpensAt } = computeImportWindowTimes(departure, overnight, now);
+      expect(windowOpensAt.toISOString()).toBe('2026-07-05T19:00:00.000Z');
+    });
+
+    it('waits to 08:00 when now is in the daytime gap [05:00, 08:00)', () => {
+      // Now = 05 Jul 06:00 EAT (03:00 UTC): desk shut (gap) → open 08:00 today.
+      const now = new Date('2026-07-05T03:00:00.000Z');
+      const { windowOpensAt } = computeImportWindowTimes(departure, overnight, now);
+      // 05 Jul 08:00 EAT = 05:00 UTC.
+      expect(windowOpensAt.toISOString()).toBe('2026-07-05T05:00:00.000Z');
+    });
+  });
 });
 
 describe('computeImportWindowTimes — overnight desk (open > close, wraps midnight)', () => {