fix: harden countdown validation and recurrence

tests/test_countdowns.py

@@ -1,3 +1,4 @@
+from copy import deepcopy
 from datetime import date
 
 from backend.lunar_support import (
@@ -265,3 +266,149 @@ def test_countdown_backup_merge_remaps_ids_owned_by_another_user(client):
     replaced = client.get("/api/v1/countdowns").json()
     assert len(replaced) == 1
     assert replaced[0]["id"] == items[0]["id"]
+
+
+def test_countdown_rejects_blank_text_and_preserves_lunar_recurrence(client):
+    boot(client)
+    assert create_countdown(client, title="   ").status_code == 422
+    assert create_countdown(client, icon="\n\t").status_code == 422
+    lunar = {
+        "calendar_mode": "lunar",
+        "lunar_month": 8,
+        "lunar_day": 4,
+        "event_date": "2026-01-01",
+    }
+    weekly = create_countdown(client, repeat_rule="weekly", **lunar)
+    monthly = create_countdown(client, repeat_rule="monthly", **lunar)
+    assert weekly.status_code == 201
+    assert monthly.status_code == 201
+    assert weekly.json()["repeat_rule"] == "weekly"
+    assert monthly.json()["repeat_rule"] == "monthly"
+
+
+def test_future_fixed_year_lunar_countdown_does_not_occur_before_anchor(client):
+    boot(client)
+    created = create_countdown(
+        client,
+        title="未来农历事件",
+        event_date="2030-01-01",
+        calendar_mode="lunar",
+        lunar_month=1,
+        lunar_day=1,
+        repeat_rule="yearly",
+    )
+    assert created.status_code == 201
+    item = created.json()
+    assert item["event_date"] == "2030-02-03"
+    assert item["display_date"] >= item["event_date"]
+
+
+def test_archived_countdown_cannot_be_edited(client):
+    boot(client)
+    item = create_countdown(client).json()
+    assert client.delete(f"/api/v1/countdowns/{item['id']}").status_code == 204
+    response = client.patch(f"/api/v1/countdowns/{item['id']}", json={"title": "归档后偷改"})
+    assert response.status_code == 409
+
+
+def test_stale_countdown_edit_is_rejected(client):
+    boot(client)
+    item = create_countdown(client).json()
+    first = client.patch(
+        f"/api/v1/countdowns/{item['id']}",
+        json={"title": "第一次修改", "expected_updated_at": item["updated_at"]},
+    )
+    assert first.status_code == 200
+    stale = client.patch(
+        f"/api/v1/countdowns/{item['id']}",
+        json={"title": "过期修改", "expected_updated_at": item["updated_at"]},
+    )
+    assert stale.status_code == 409
+    current = client.get("/api/v1/countdowns").json()[0]
+    assert current["title"] == "第一次修改"
+
+
+def test_restore_rejects_malformed_countdowns_atomically(client):
+    boot(client)
+    original = create_countdown(client, title="必须保留").json()
+    exported = client.get("/api/v1/export").json()
+
+    malformed = deepcopy(exported)
+    malformed["countdowns"][0]["archived_at"] = "not-a-date"
+    response = client.post("/api/v1/restore", params={"mode": "replace"}, json=malformed)
+    assert response.status_code == 422
+    assert [item["id"] for item in client.get("/api/v1/countdowns").json()] == [original["id"]]
+
+    for invalid in (None, 7):
+        malformed = deepcopy(exported)
+        malformed["countdowns"] = invalid
+        response = client.post("/api/v1/restore", params={"mode": "replace"}, json=malformed)
+        assert response.status_code == 422
+        assert [item["id"] for item in client.get("/api/v1/countdowns").json()] == [original["id"]]
+
+    duplicate = deepcopy(exported)
+    duplicate["countdowns"].append(deepcopy(duplicate["countdowns"][0]))
+    response = client.post("/api/v1/restore", params={"mode": "replace"}, json=duplicate)
+    assert response.status_code == 422
+    assert [item["id"] for item in client.get("/api/v1/countdowns").json()] == [original["id"]]
+
+    two_pinned = deepcopy(exported)
+    extra = deepcopy(two_pinned["countdowns"][0])
+    extra["id"] = "34deeea0-d976-4581-b378-a66f28623de8"
+    extra["title"] = "第二个置顶"
+    two_pinned["countdowns"][0]["pinned"] = True
+    extra["pinned"] = True
+    two_pinned["countdowns"].append(extra)
+    response = client.post("/api/v1/restore", params={"mode": "replace"}, json=two_pinned)
+    assert response.status_code == 200
+    assert sum(item["pinned"] for item in client.get("/api/v1/countdowns").json()) == 1
+
+
+def test_restore_validates_lunar_metadata_booleans_and_count(client):
+    boot(client)
+    item = create_countdown(
+        client,
+        title="农历备份",
+        event_date="2025-01-01",
+        calendar_mode="lunar",
+        lunar_month=8,
+        lunar_day=4,
+    ).json()
+    exported = client.get("/api/v1/export").json()
+
+    contradictory = deepcopy(exported)
+    contradictory["countdowns"][0]["event_date"] = "2025-01-01"
+    assert client.post("/api/v1/restore", params={"mode": "replace"}, json=contradictory).status_code == 422
+    assert client.get("/api/v1/countdowns").json()[0]["id"] == item["id"]
+
+    string_booleans = deepcopy(exported)
+    string_booleans["countdowns"][0]["ignore_year"] = "false"
+    string_booleans["countdowns"][0]["pinned"] = "false"
+    assert client.post("/api/v1/restore", params={"mode": "replace"}, json=string_booleans).status_code == 422
+
+    clean = deepcopy(exported)
+    clean["countdowns"][0]["id"] = "13ad79f4-78bc-4a53-a952-e1da84be1a9a"
+    restored = client.post("/api/v1/restore", params={"mode": "merge"}, json=clean)
+    assert restored.status_code == 200
+    assert restored.json()["restored"] == 1
+
+
+def test_restore_accepts_lunar_dates_whose_solar_anchor_is_in_next_year(client):
+    boot(client)
+    created = create_countdown(
+        client,
+        title="跨公历年农历日",
+        event_date="2001-01-01",
+        calendar_mode="lunar",
+        lunar_month=12,
+        lunar_day=20,
+    )
+    assert created.status_code == 201
+    assert created.json()["event_date"] == "2002-02-01"
+    exported = client.get("/api/v1/export").json()
+
+    restored = client.post("/api/v1/restore", params={"mode": "replace"}, json=exported)
+    assert restored.status_code == 200
+    item = client.get("/api/v1/countdowns").json()[0]
+    assert item["event_date"] == "2002-02-01"
+    assert item["lunar_year"] == 2001