feat: Enhance group selection logic to exclude duplicates for main schedules and past documents

test/directory.test.js

@@ -166,3 +166,32 @@ test("Поиск группы: любое написание, без учёта
   assert.equal(findGroups(idx, {}).results.length, 0);
   assert.equal(findGroups(idx, {}).total, 4);
 });
+
+test("Выбор группы: зачёты не дублируют группу с основным расписанием", async () => {
+  const { findGroups } = await import("../server/directory.js");
+  const credits = parseDocx(fixture("isf-credits-26-arh"), { name: "26-АРХ.docx" });
+  const main = { ...credits, period: "Осенний семестр" };
+  const doc = (id, schedule) => ({ id, file: { id, name: "26-АРХ.docx", faculty: "ИСФ", course: "1 курс" }, schedule });
+  // With a semester timetable the credits stay in the session countdown, not in the picker.
+  const both = findGroups({ docs: [doc("main", main), doc("credits", credits)] }, { q: "26-АРХ" });
+  assert.deepEqual(both.results.map((r) => [r.group, r.fileId]), [["26-АРХ", "main"]]);
+  assert.equal(both.total, 1);
+  // A group with only a credit schedule can still open it.
+  const only = findGroups({ docs: [doc("credits", credits)] }, { q: "26-АРХ" });
+  assert.deepEqual(only.results.map((r) => [r.group, r.fileId, r.period]), [["26-АРХ", "credits", "Зачёты"]]);
+});
+
+test("Выбор группы: прошедший документ с датами не дублирует основное расписание", async () => {
+  const { findGroups } = await import("../server/directory.js");
+  // A document dated 8–27 June 2026, like an orientation week, beside the group's semester timetable.
+  const dated = parseDocx(fixture("itzs-summer-2026"), { name: "23-ИТзс.docx" });
+  const main = { ...dated, period: "Осенний семестр", lessons: dated.lessons.map(({ date, ...l }) => l) };
+  const doc = (id, schedule) => ({ id, file: { id, name: `${id}.docx` }, schedule });
+  const idx = { docs: [doc("main", main), doc("dated", dated)] };
+  const ids = (today) => findGroups(idx, { q: "23-ИТзс", today }).results.map((r) => r.fileId);
+  assert.deepEqual(ids("2026-10-19"), ["main"]);
+  // Before it is over, both are offered.
+  assert.deepEqual(ids("2026-06-20").sort(), ["dated", "main"]);
+  // Alone, even a finished one stays: it is all the group has.
+  assert.deepEqual(findGroups({ docs: [doc("dated", dated)] }, { q: "23-ИТзс", today: "2026-10-19" }).results.length, 1);
+});