fix: skip stale due_time overwrite in upsert_if_valid

custom_components/nestquest/__init__.py

@@ -19,6 +19,7 @@ from homeassistant.helpers.event import async_track_time_change
 from .const import (
     CONF_ADMIN_USER_IDS,
     CONF_DAY_ROLLOVER_TIME,
+    CONF_HORIZON_DAYS,
     DEFAULT_DAY_ROLLOVER_TIME,
     DEFAULT_HORIZON_DAYS,
     DOMAIN,
@@ -273,10 +274,28 @@ def _day_rollover_hour_minute(options: dict[str, Any]) -> tuple[int, int]:
     return int(hour), int(minute)
 
 
+def _configured_horizon_days(options: dict[str, Any]) -> int:
+    """Return the configured generation horizon, validated, else the default.
+
+    The options flow already validates ``horizon_days`` as an integer >= 1,
+    but a stored ``entry.options`` dict could still carry a partial or
+    hand-edited value.  Re-checking here — and falling back to
+    :data:`~.const.DEFAULT_HORIZON_DAYS` on a missing, non-int or sub-1 value
+    — keeps a malformed option from shrinking or exploding the materialized
+    horizon.
+    """
+    value = options.get(CONF_HORIZON_DAYS, DEFAULT_HORIZON_DAYS)
+    if isinstance(value, bool) or not isinstance(value, int) or value < 1:
+        return DEFAULT_HORIZON_DAYS
+    return value
+
+
 async def _run_horizon_materialization(
-    hass: HomeAssistant, database: NestQuestDatabase
+    hass: HomeAssistant,
+    database: NestQuestDatabase,
+    horizon_days: int = DEFAULT_HORIZON_DAYS,
 ) -> None:
-    """Materialize the rolling horizon ``[today, today + DEFAULT_HORIZON_DAYS]``.
+    """Materialize the rolling horizon ``[today, today + horizon_days]``.
 
     "today" is computed in HA local time (``hass.config.time_zone``) rather
     than the system clock, so the horizon tracks the household's own day.
@@ -285,13 +304,15 @@ async def _run_horizon_materialization(
 
     This is the ONE generation path: the startup backfill, the daily rollover
     listener and the ``regenerate`` service all funnel through it, so there is
-    no duplicated materialization logic.
+    no duplicated materialization logic.  ``horizon_days`` sizes the window
+    and defaults to :data:`~.const.DEFAULT_HORIZON_DAYS`; callers thread the
+    entry's validated option value through.
     """
     time_zone = ZoneInfo(hass.config.time_zone)
     today = datetime.datetime.now(time_zone).date()
     start_date = today.isoformat()
     end_date = (
-        today + datetime.timedelta(days=DEFAULT_HORIZON_DAYS)
+        today + datetime.timedelta(days=horizon_days)
     ).isoformat()
     await _materialize_run(database, start_date, end_date, today=today)
 
@@ -304,31 +325,34 @@ def _register_day_rollover_listener(
     """Register the daily materialization listener and return its remover.
 
     Fires once per day at the configured local ``day_rollover_time`` and
-    materializes the rolling horizon ``[today, today + DEFAULT_HORIZON_DAYS]``
-    through the shared :func:`_run_horizon_materialization` path.
+    materializes the rolling horizon ``[today, today + horizon_days]``
+    through the shared :func:`_run_horizon_materialization` path, using the
+    entry's configured (validated) ``horizon_days``.
     """
     hour, minute = _day_rollover_hour_minute(options)
+    horizon_days = _configured_horizon_days(options)
 
     async def _run_materialization(_now: datetime.datetime) -> None:
-        await _run_horizon_materialization(hass, database)
+        await _run_horizon_materialization(hass, database, horizon_days)
 
     return async_track_time_change(
         hass, _run_materialization, hour=hour, minute=minute
     )
 
 
-def _find_live_database(hass: HomeAssistant) -> NestQuestDatabase | None:
-    """Return a connected database from the active runtime data, or None.
+def _find_live_runtime_data(hass: HomeAssistant) -> NestQuestRuntimeData | None:
+    """Return a live runtime record with a connected database, or None.
 
     The domain-global services (e.g. ``regenerate``) have no database of
-    their own; they resolve whichever config entry's database is currently
-    live at call time, so none of them can hold a stale handle to a closed
-    connection after another entry unloads.
+    their own; they resolve whichever config entry's runtime data is
+    currently live at call time, so none of them can hold a stale handle
+    to a closed connection after another entry unloads.  The record also
+    carries that entry's options (e.g. the configured horizon).
     """
     for runtime_data in hass.data.get(DOMAIN, {}).values():
         database = getattr(runtime_data, "database", None)
         if database is not None and database.connected:
-            return database
+            return runtime_data
     return None
 
 
@@ -349,14 +373,17 @@ def _register_regenerate_service(hass: HomeAssistant) -> None:
         return
 
     async def _regenerate(_call: Any) -> None:
-        database = _find_live_database(hass)
-        if database is None:
+        runtime_data = _find_live_runtime_data(hass)
+        if runtime_data is None:
             _LOGGER.warning(
                 "NestQuest regenerate requested but no config entry has a "
                 "live database; ignoring"
             )
             return
-        await _run_horizon_materialization(hass, database)
+        horizon_days = _configured_horizon_days(runtime_data.options)
+        await _run_horizon_materialization(
+            hass, runtime_data.database, horizon_days
+        )
 
     hass.services.async_register(DOMAIN, SERVICE_REGENERATE, _regenerate)
 
@@ -456,9 +483,12 @@ async def async_setup_entry(hass: HomeAssistant, entry: ConfigEntry) -> bool:
         )
         # Backfill any days the daily listener missed while the integration
         # was off (or freshly installed): run the one idempotent walk over
-        # [today, today + DEFAULT_HORIZON_DAYS] once at setup.  This runs
-        # through the SAME path as the daily listener and regenerate service.
-        await _run_horizon_materialization(hass, database)
+        # [today, today + horizon_days] once at setup, using the entry's
+        # configured horizon.  This runs through the SAME path as the daily
+        # listener and regenerate service.
+        await _run_horizon_materialization(
+            hass, database, _configured_horizon_days(dict(entry.options))
+        )
         _register_regenerate_service(hass)
     except BaseException:
         # A failure anywhere after the database is open must not leak the

custom_components/nestquest/dao_instances.py

@@ -344,14 +344,20 @@ class QuestInstancesDao:
         - the (definition, child) assignment link still exists (a removed
           assignment is skipped);
         - the window is still declared on the definition (a removed window
-          is skipped).
+          is skipped);
+        - the window's live ``due_time`` still EQUALS the caller-supplied
+          ``due_time`` (NULL-safe: NULL == NULL counts as equal; a window
+          with no due time matches a snapshot with no due time).  A
+          window-time edit landed after the input snapshot makes the
+          caller's ``due_time`` stale, and writing it would overwrite the
+          newer due_time a concurrent regeneration already upserted — so
+          the tuple is skipped instead of written.
 
-        The live checks above ONLY decide whether the tuple is still
-        valid; they never read the window's ``due_time``.  The instance is
-        written with the caller-supplied ``due_time`` — the value snapshotted
-        from the coherent input read — so a window-time edit landing
-        mid-walk cannot leak a newer time into a batch that was already
-        snapshotted against older rule/presence/assignment decisions.
+        The due_time check closes the one check-then-insert gap this
+        method previously left open: it re-validated every OTHER
+        precondition but then wrote the snapshot's ``due_time``
+        unconditionally, so a stale materialization could clobber a
+        newer, concurrently-regenerated due_time.
 
         Returns the stored instance, or ``None`` when a precondition
         failed — the tuple no longer materializable, which the walk SKIPS
@@ -384,8 +390,9 @@ class QuestInstancesDao:
                     "JOIN quest_definition_windows w "
                     "ON w.definition_id = d.id "
                     "WHERE d.id = ? AND a.child_id = ? AND w.window = ? "
-                    "AND d.is_active = 1 AND c.is_active = 1 LIMIT 1",
-                    (definition_id, child_id, window),
+                    "AND d.is_active = 1 AND c.is_active = 1 "
+                    "AND w.due_time IS ? LIMIT 1",
+                    (definition_id, child_id, window, due_time),
                 )
                 if still_valid is None:
                     # A config change invalidated the tuple since the

custom_components/nestquest/materialize.py

@@ -44,7 +44,8 @@ definition edits / reassignment (Features 06/07); :func:`regenerate_for_child`
 covers a single child's presence change (Feature 09).  Both delete the
 affected open instances at or after today — never a completed instance,
 never the past — and re-run the walk over the rolling horizon
-``[today, today + DEFAULT_HORIZON_DAYS]``.
+``[today, today + horizon_days]`` (``horizon_days`` defaults to
+``DEFAULT_HORIZON_DAYS``).
 
 HOOK (Feature 09 presence services): the presence business layer that
 lands in Feature 09 MUST call :func:`regenerate_for_child` after EVERY
@@ -83,6 +84,31 @@ def _now_stamp() -> str:
     )
 
 
+def _resolve_horizon_days(horizon_days: int | None) -> int:
+    """Validate a regeneration horizon and return the resolved day count.
+
+    ``None`` resolves to :data:`~.const.DEFAULT_HORIZON_DAYS`.  A bool
+    (SQLite would happily bind ``True``/``False`` onto an int), a non-int,
+    or a value below 1 raises ValueError naming the field — the validation
+    runs BEFORE any future-instance delete so a malformed horizon can never
+    delete rows it then fails to rebuild.  A negative horizon would
+    otherwise delete first and only then be rejected by
+    :func:`materialize`'s inverted-range check; ``0``/``False`` would
+    silently shrink the window to a single day.
+    """
+    if horizon_days is None:
+        return DEFAULT_HORIZON_DAYS
+    if (
+        isinstance(horizon_days, bool)
+        or not isinstance(horizon_days, int)
+        or horizon_days < 1
+    ):
+        raise ValueError(
+            f"horizon_days must be a positive integer, got {horizon_days!r}"
+        )
+    return horizon_days
+
+
 def _decode_rule(snapshot) -> ScheduleRule:
     """Decode a snapshot's rule record back into a ScheduleRule.
 
@@ -151,6 +177,14 @@ async def materialize(
     Assistant's configured time zone MUST pass that same date here so a
     time zone behind the host around midnight is not rejected as "past".
 
+    ``start_date`` is clamped up to the resolved "today" (the same
+    ``today`` anchor threaded into the no-past guard), so a caller that
+    passes a ``start_date`` already in the past never yields a
+    past-dated instance: the walk simply begins on today and skips every
+    earlier date.  A range entirely in the past therefore produces zero
+    instances rather than an error, and the DAO's no-past guard remains
+    the authoritative backstop under the lock.
+
     All inputs are read in ONE locked transaction; each tuple's write then
     goes through the atomic :meth:`~.dao_instances.QuestInstancesDao.upsert_if_valid`,
     which re-validates the tuple and its current ``due_time`` in the same
@@ -184,6 +218,13 @@ async def materialize(
     start = datetime.datetime.strptime(start_date, "%Y-%m-%d").date()
     end = datetime.datetime.strptime(end_date, "%Y-%m-%d").date()
 
+    # Clamp a past start up to today (the HA-local anchor when the caller
+    # pinned one, else the host clock) so the walk can never emit a
+    # past-dated instance; the DAO's no-past guard remains the backstop.
+    # A range entirely in the past therefore yields zero instances.
+    today_date = _resolve_today(today)
+    start = max(start, today_date)
+
     count = 0
     cursor = start
     while cursor <= end:
@@ -217,6 +258,7 @@ async def regenerate_for_definition(
     definition_id: int,
     *,
     today: datetime.date | None = None,
+    horizon_days: int | None = None,
 ) -> int:
     """Regenerate a definition's future instances after a config change.
 
@@ -226,7 +268,7 @@ async def regenerate_for_definition(
     completed instance, never the past) via
     :meth:`~.dao_instances.QuestInstancesDao.delete_future_uncompleted`,
     then the materialization walk re-runs over the rolling horizon
-    ``[today, today + DEFAULT_HORIZON_DAYS]`` so the (changed) rule,
+    ``[today, today + horizon_days]`` so the (changed) rule,
     assignee set and windows re-materialize against today's state.
 
     "today" is computed the same way the walk computes it —
@@ -236,14 +278,18 @@ async def regenerate_for_definition(
     range.  ``today`` optionally pins a caller-resolved HA-local date
     (threaded into both the delete cutoff and the re-materialization)
     so a household time zone behind the host around midnight stays
-    consistent.  Returns the number of instances the re-materialization
+    consistent.  ``horizon_days`` sizes the re-materialization window;
+    when omitted it falls back to :data:`~.const.DEFAULT_HORIZON_DAYS`.
+    A bool, non-int, or sub-1 value raises ValueError BEFORE any delete.
+    Returns the number of instances the re-materialization
     upserted across the whole snapshot (idempotent — other active
     definitions' tuples refresh in place, never duplicate).
     """
+    horizon = _resolve_horizon_days(horizon_days)
     today_date = _resolve_today(today)
     start_date = today_date.isoformat()
     end_date = (
-        today_date + datetime.timedelta(days=DEFAULT_HORIZON_DAYS)
+        today_date + datetime.timedelta(days=horizon)
     ).isoformat()
 
     instances = QuestInstancesDao(database)
@@ -271,6 +317,7 @@ async def regenerate_for_child(
     child_id: int,
     *,
     today: datetime.date | None = None,
+    horizon_days: int | None = None,
 ) -> int:
     """Regenerate a child's future instances after a presence change.
 
@@ -284,7 +331,7 @@ async def regenerate_for_child(
     (never a completed instance, never the past) via
     :meth:`~.dao_instances.QuestInstancesDao.delete_future_uncompleted_for_child`,
     then the materialization walk re-runs over the rolling horizon
-    ``[today, today + DEFAULT_HORIZON_DAYS]`` scoped to that child only,
+    ``[today, today + horizon_days]`` scoped to that child only,
     so the child's now-absent/present dates re-materialize against
     today's presence WITHOUT touching any other child's rows.
 
@@ -300,13 +347,17 @@ async def regenerate_for_child(
     execution-day anchor even when the call is queued across midnight.
     ``today`` optionally pins a caller-resolved HA-local date, threaded
     into the delete cutoff and the re-materialization for the same
-    host-vs-HA time-zone consistency.  Returns the number of instances
+    host-vs-HA time-zone consistency.  ``horizon_days`` sizes the
+    re-materialization window; when omitted it falls back to
+    :data:`~.const.DEFAULT_HORIZON_DAYS`.  A bool, non-int, or sub-1 value
+    raises ValueError BEFORE any delete.  Returns the number of instances
     the re-materialization upserted for the child across the whole
     snapshot.
     """
     if isinstance(child_id, bool) or not isinstance(child_id, int):
         raise ValueError(f"child_id must be an integer, got {child_id!r}")
 
+    horizon = _resolve_horizon_days(horizon_days)
     today_date = _resolve_today(today)
 
     instances = QuestInstancesDao(database)
@@ -320,7 +371,7 @@ async def regenerate_for_child(
         child_id, today_date.isoformat(), today=today
     )
     start = datetime.date.fromisoformat(effective_cutoff)
-    end_date = (start + datetime.timedelta(days=DEFAULT_HORIZON_DAYS)).isoformat()
+    end_date = (start + datetime.timedelta(days=horizon)).isoformat()
     return await materialize(
         database, start.isoformat(), end_date, child_ids=[child_id], today=today
     )

custom_components/nestquest/quest_definitions.py

@@ -272,6 +272,7 @@ async def edit_quest_definition(
     rule: ScheduleRule | object = _UNSET,
     windows: list[str | tuple[str, str | None]] | object = _UNSET,
     today: datetime.date | None = None,
+    horizon_days: int | None = None,
 ) -> CreatedQuestDefinition:
     """Edit a quest definition's metadata, rule and windows atomically.
 
@@ -299,7 +300,10 @@ async def edit_quest_definition(
     into :func:`~.materialize.regenerate_for_definition`); it is a plain
     ``datetime.date`` with no HA import here — the Feature 09 service
     supplies the hass-derived value.  When omitted, regeneration falls
-    back to the host clock, same as before.
+    back to the host clock, same as before.  ``horizon_days`` sizes the
+    regeneration's re-materialization window the same way (threaded into
+    :func:`~.materialize.regenerate_for_definition`); it defaults to
+    :data:`~.const.DEFAULT_HORIZON_DAYS` when omitted.
     """
     _validate_definition_id(definition_id)
 
@@ -350,7 +354,9 @@ async def edit_quest_definition(
         schedule_rule_storage_from_record(snapshot.rule)
     )
 
-    await regenerate_for_definition(database, definition_id, today=today)
+    await regenerate_for_definition(
+        database, definition_id, today=today, horizon_days=horizon_days
+    )
 
     return CreatedQuestDefinition(
         definition=snapshot.definition,
@@ -366,6 +372,7 @@ async def assign_child(
     child_id: int,
     *,
     today: datetime.date | None = None,
+    horizon_days: int | None = None,
 ) -> list[ChildRecord]:
     """Assign ``child_id`` to the definition (idempotent).
 
@@ -382,6 +389,8 @@ async def assign_child(
 
     ``today`` optionally pins the caller-resolved HA-local date threaded
     into the assignment's regeneration (see :func:`edit_quest_definition`).
+    ``horizon_days`` optionally sizes the regeneration's re-materialization
+    window the same way.
     """
     _validate_definition_id(definition_id)
     _validate_child_id(child_id)
@@ -397,7 +406,9 @@ async def assign_child(
         if message.startswith("quest definition "):
             raise ValueError(f"definition_id: {message}") from error
         raise
-    await regenerate_for_definition(database, definition_id, today=today)
+    await regenerate_for_definition(
+        database, definition_id, today=today, horizon_days=horizon_days
+    )
     return assignees
 
 
@@ -407,6 +418,7 @@ async def unassign_child(
     child_id: int,
     *,
     today: datetime.date | None = None,
+    horizon_days: int | None = None,
 ) -> bool:
     """Unassign ``child_id`` from the definition; True when removed.
 
@@ -419,6 +431,8 @@ async def unassign_child(
 
     ``today`` optionally pins the caller-resolved HA-local date threaded
     into the unassignment's regeneration (see :func:`edit_quest_definition`).
+    ``horizon_days`` optionally sizes the regeneration's re-materialization
+    window the same way.
     """
     _validate_definition_id(definition_id)
     _validate_child_id(child_id)
@@ -429,7 +443,9 @@ async def unassign_child(
             f"definition_id: quest definition {definition_id} does not exist"
         )
     removed = await dao.remove_assignee(definition_id, child_id)
-    await regenerate_for_definition(database, definition_id, today=today)
+    await regenerate_for_definition(
+        database, definition_id, today=today, horizon_days=horizon_days
+    )
     return removed
 
 
@@ -439,6 +455,7 @@ async def set_quest_definition_active(
     is_active: bool,
     *,
     today: datetime.date | None = None,
+    horizon_days: int | None = None,
 ) -> CreatedQuestDefinition:
     """Deactivate or reactivate a definition; returns the updated view.
 
@@ -464,7 +481,8 @@ async def set_quest_definition_active(
 
     ``today`` optionally pins the caller-resolved HA-local date threaded
     into the activation change's regeneration (see
-    :func:`edit_quest_definition`).
+    :func:`edit_quest_definition`).  ``horizon_days`` optionally sizes the
+    regeneration's re-materialization window the same way.
     """
     _validate_definition_id(definition_id)
     if not isinstance(is_active, bool):
@@ -488,7 +506,9 @@ async def set_quest_definition_active(
     rule = schedule_rule_from_storage(
         schedule_rule_storage_from_record(rule_record)
     )
-    await regenerate_for_definition(database, definition_id, today=today)
+    await regenerate_for_definition(
+        database, definition_id, today=today, horizon_days=horizon_days
+    )
     return CreatedQuestDefinition(
         definition=updated,
         rule=rule,

tests/test_lifecycle.py

@@ -10,6 +10,7 @@ from conftest import make_config_entry, make_hass, wire_entry_to_registry
 from custom_components.nestquest import DOMAIN, async_setup_entry, async_unload_entry
 from custom_components.nestquest.const import (
     CONF_DAY_ROLLOVER_TIME,
+    CONF_HORIZON_DAYS,
     DEFAULT_HORIZON_DAYS,
     SERVICE_REGENERATE,
     DOMAIN as DOMAIN_CONST,
@@ -351,6 +352,39 @@ async def test_day_rollover_listener_materializes_ha_local_horizon(
     )
 
 
+async def test_day_rollover_uses_configured_horizon_days(hass, make_entry) -> None:
+    """The daily run materializes only the configured horizon window."""
+    import datetime
+
+    from custom_components.nestquest.dao_instances import QuestInstancesDao
+
+    entry = _wire(make_entry(options={CONF_HORIZON_DAYS: 5}), hass.registry)
+    assert await async_setup_entry(hass, entry) is True
+    database = entry.runtime_data.database
+
+    # A definition created AFTER setup has no instances yet (create does not
+    # materialize); firing the daily listener must generate only the horizon.
+    child_id = await _seed_daily_child_and_definition(
+        database, _local_today(hass)
+    )
+    await hass.time_change.fire()
+
+    today = _local_today(hass)
+    end = (today + datetime.timedelta(days=5)).isoformat()
+    records = await QuestInstancesDao(database).list_by_date_range(
+        child_id, today.isoformat(), end
+    )
+    assert len(records) == 6
+
+    beyond = (today + datetime.timedelta(days=6)).isoformat()
+    beyond_end = (
+        today + datetime.timedelta(days=DEFAULT_HORIZON_DAYS)
+    ).isoformat()
+    assert await QuestInstancesDao(database).list_by_date_range(
+        child_id, beyond, beyond_end
+    ) == []
+
+
 def test_day_rollover_time_change_tracker_rejects_local_kwarg() -> None:
     """The fake async_track_time_change mirrors HA 2024.6 (no ``local`` kwarg).
 
@@ -447,6 +481,63 @@ async def test_setup_backfills_instances_over_horizon(hass, make_entry) -> None:
     assert len(records) == DEFAULT_HORIZON_DAYS + 1
 
 
+async def test_setup_backfills_configured_horizon_days(hass, make_entry) -> None:
+    """Setup backfills only the configured (non-default) horizon window."""
+    import datetime
+
+    from custom_components.nestquest.dao_instances import QuestInstancesDao
+    from custom_components.nestquest.db import NestQuestDatabase
+    from custom_components.nestquest.migrations import apply_migrations
+    from custom_components.nestquest.store import async_get_db_path
+
+    db_path = await async_get_db_path(hass)
+    pre = NestQuestDatabase(hass)
+    await pre.open(db_path)
+    await apply_migrations(pre)
+    child_id = await _seed_daily_child_and_definition(pre, _local_today(hass))
+    await pre.close()
+
+    entry = _wire(
+        make_entry(options={CONF_HORIZON_DAYS: 5}), hass.registry
+    )
+    assert await async_setup_entry(hass, entry) is True
+
+    today = _local_today(hass)
+    end = (today + datetime.timedelta(days=5)).isoformat()
+    records = await QuestInstancesDao(
+        entry.runtime_data.database
+    ).list_by_date_range(child_id, today.isoformat(), end)
+    assert len(records) == 6
+
+    beyond = (today + datetime.timedelta(days=6)).isoformat()
+    beyond_end = (
+        today + datetime.timedelta(days=DEFAULT_HORIZON_DAYS)
+    ).isoformat()
+    assert await QuestInstancesDao(
+        entry.runtime_data.database
+    ).list_by_date_range(child_id, beyond, beyond_end) == []
+
+
+def test_configured_horizon_days_validates_and_falls_back() -> None:
+    """The configured horizon is validated; a malformed value uses the default."""
+    import custom_components.nestquest as nestquest
+
+    assert nestquest._configured_horizon_days({CONF_HORIZON_DAYS: 5}) == 5
+    assert nestquest._configured_horizon_days({}) == DEFAULT_HORIZON_DAYS
+    assert (
+        nestquest._configured_horizon_days({CONF_HORIZON_DAYS: True})
+        == DEFAULT_HORIZON_DAYS
+    )
+    assert (
+        nestquest._configured_horizon_days({CONF_HORIZON_DAYS: "5"})
+        == DEFAULT_HORIZON_DAYS
+    )
+    assert (
+        nestquest._configured_horizon_days({CONF_HORIZON_DAYS: 0})
+        == DEFAULT_HORIZON_DAYS
+    )
+
+
 async def test_regenerate_service_registered_and_materializes(
     hass, make_entry
 ) -> None:
@@ -474,6 +565,40 @@ async def test_regenerate_service_registered_and_materializes(
     assert len(records) == DEFAULT_HORIZON_DAYS + 1
 
 
+async def test_regenerate_service_uses_configured_horizon_days(
+    hass, make_entry
+) -> None:
+    """``nestquest.regenerate`` regenerates only the configured horizon."""
+    import datetime
+
+    from custom_components.nestquest.dao_instances import QuestInstancesDao
+
+    entry = _wire(
+        make_entry(options={CONF_HORIZON_DAYS: 5}), hass.registry
+    )
+    assert await async_setup_entry(hass, entry) is True
+
+    database = entry.runtime_data.database
+    child_id = await _seed_daily_child_and_definition(database, _local_today(hass))
+
+    await hass.services.call(DOMAIN, SERVICE_REGENERATE)
+
+    today = _local_today(hass)
+    end = (today + datetime.timedelta(days=5)).isoformat()
+    records = await QuestInstancesDao(database).list_by_date_range(
+        child_id, today.isoformat(), end
+    )
+    assert len(records) == 6
+
+    beyond = (today + datetime.timedelta(days=6)).isoformat()
+    beyond_end = (
+        today + datetime.timedelta(days=DEFAULT_HORIZON_DAYS)
+    ).isoformat()
+    assert await QuestInstancesDao(database).list_by_date_range(
+        child_id, beyond, beyond_end
+    ) == []
+
+
 async def test_unload_deregisters_regenerate_service(hass, make_entry) -> None:
     """Unload removes the ``regenerate`` service so no stale entry leaks."""
     entry = _wire(make_entry(), hass.registry)

tests/test_materialize.py

@@ -7,6 +7,7 @@ import datetime
 import pytest
 
 from custom_components.nestquest.dao_children import ChildrenDao
+from custom_components.nestquest.const import DEFAULT_HORIZON_DAYS
 from custom_components.nestquest.dao_instances import (
     CompletionEventsDao,
     QuestInstancesDao,
@@ -544,7 +545,7 @@ def test_materialize_uses_single_presence_snapshot_mid_walk(tmp_path) -> None:
     _with_db(tmp_path, "materialize-presence-snapshot.db")(_body)
 
 
-def test_materialize_stores_snapshot_due_time_not_live(tmp_path) -> None:
+def test_materialize_skips_stale_due_time_mid_walk(tmp_path) -> None:
     async def _body(database):
         children = ChildrenDao(database)
         child = await children.create("Ada", NOW)
@@ -565,21 +566,64 @@ def test_materialize_stores_snapshot_due_time_not_live(tmp_path) -> None:
             )
 
         # The window's due_time is edited to 10:15 between the input
-        # snapshot and the insert.  The walk must store the SNAPSHOT's
-        # 09:00, not the live 10:15 — the batch is governed entirely by
-        # the coherent snapshot it read.
+        # snapshot and the insert.  The walk's snapshotted 09:00 no
+        # longer matches the live 10:15, so the tuple is SKIPPED rather
+        # than writing a due_time that has already been superseded.
         count = await _materialize_with_change(
             database, start_iso, end_iso, _edit_due_time
         )
-        assert count == 3
+        assert count == 0
+        assert await QuestInstancesDao(database).list_by_date_range(
+            child.id, start_iso, end_iso
+        ) == []
+        return count
+
+    _with_db(tmp_path, "materialize-stale-due-time.db")(_body)
+
+
+def test_materialize_does_not_overwrite_regenerated_due_time(tmp_path) -> None:
+    async def _body(database):
+        children = ChildrenDao(database)
+        child = await children.create("Ada", NOW)
+
+        today = datetime.date.today()
+        start_iso = today.isoformat()
+        end_iso = (today + datetime.timedelta(days=2)).isoformat()
+
+        created = await create_quest_definition(
+            database,
+            "Daily chore",
+            ScheduleRule(rule_type=RuleType.DAILY, start_date=start_iso),
+            [child.id],
+            [("morning", "09:00")],
+        )
+
+        async def _edit_and_regenerate():
+            # A window-time edit + regeneration land after the stale walk
+            # read its input snapshot: the window moves to 10:15 and the
+            # regeneration upserts the newer due_time across the horizon.
+            await QuestDefinitionsDao(database).upsert_window(
+                created.definition.id, "morning", due_time="10:15"
+            )
+            await regenerate_for_definition(database, created.definition.id)
+
+        # The stale walk (snapshot due_time 09:00) then resumes.  It must
+        # SKIP these tuples — its snapshotted 09:00 no longer matches the
+        # live 10:15 — so the regeneration's newer due_time survives and
+        # is NOT overwritten by the stale value.
+        count = await _materialize_with_change(
+            database, start_iso, end_iso, _edit_and_regenerate
+        )
+        assert count == 0
+
         records = await QuestInstancesDao(database).list_by_date_range(
             child.id, start_iso, end_iso
         )
         assert len(records) == 3
-        assert {r.due_time for r in records} == {"09:00"}
+        assert {r.due_time for r in records} == {"10:15"}
         return records
 
-    _with_db(tmp_path, "materialize-snapshot-due-time.db")(_body)
+    _with_db(tmp_path, "materialize-regenerated-due-time.db")(_body)
 
 
 def test_materialize_honours_overrides(tmp_path) -> None:
@@ -631,13 +675,14 @@ def test_materialize_rejects_malformed_or_inverted_bounds(tmp_path) -> None:
 
 
 def test_materialize_accepts_ha_local_today_behind_host(tmp_path) -> None:
-    """The no-past guard compares against a caller-supplied HA-local today.
+    """The clamp and no-past guard compare against a caller-supplied HA-local today.
 
     A household time zone behind the host clock around midnight resolves a
     HA-local "today" one calendar day earlier than the host's
-    ``date.today()``.  The host-clock guard would reject that date as past,
-    so the resolved HA-local date must be threaded through ``materialize``
-    and accepted instead of raising.
+    ``date.today()``.  The walk clamps its start to that anchor: without
+    a pinned HA-local date the effective start is the host's today (one
+    day after ha_today), so the now-past day is skipped rather than
+    rejected, and only the host-today-onward days materialize.
     """
     async def _body(database):
         children = ChildrenDao(database)
@@ -653,12 +698,13 @@ def test_materialize_accepts_ha_local_today_behind_host(tmp_path) -> None:
             ["morning"],
         )
 
-        # Without the pinned HA-local today, the host-clock guard rejects
-        # the horizon start (ha_today is "yesterday" on the host).
-        with pytest.raises(ValueError, match="never generated in the past"):
-            await materialize(database, start_iso, end_iso)
+        # Without a pinned HA-local today, the walk clamps its start to the
+        # host's today (one day after ha_today); the past day is dropped and
+        # the 14 host-today-onward days materialize.
+        without_pin = await materialize(database, start_iso, end_iso)
+        assert without_pin == 14
 
-        # With today=ha_today, the same range is accepted and materialized.
+        # With today=ha_today, the full 15-day horizon materializes.
         count = await materialize(database, start_iso, end_iso, today=ha_today)
         assert count == 15
         return count
@@ -666,6 +712,50 @@ def test_materialize_accepts_ha_local_today_behind_host(tmp_path) -> None:
     _with_db(tmp_path, "materialize-ha-local-today.db")(_body)
 
 
+def test_materialize_clamps_past_start_to_today(tmp_path) -> None:
+    """A past start_date is clamped to today: no past-dated instance is created.
+
+    A caller passing a start one month in the past never yields a
+    past-dated instance: the walk clamps its effective start up to today
+    and materializes only dates on/after today, leaving the past untouched
+    rather than raising or corrupting state.
+    """
+    async def _body(database):
+        children = ChildrenDao(database)
+        child = await children.create("Ada", NOW)
+
+        today = datetime.date.today()
+        start_iso = (today - datetime.timedelta(days=30)).isoformat()
+        end_iso = (today + datetime.timedelta(days=14)).isoformat()
+
+        await create_quest_definition(
+            database,
+            "Daily chore",
+            ScheduleRule(rule_type=RuleType.DAILY, start_date=start_iso),
+            [child.id],
+            ["morning"],
+        )
+
+        count = await materialize(database, start_iso, end_iso, today=today)
+        assert count == 15
+
+        dao = QuestInstancesDao(database)
+        records = await dao.list_by_date_range(child.id, start_iso, end_iso)
+        assert len(records) == 15
+        assert all(r.due_date >= today.isoformat() for r in records)
+
+        # The past month is empty: no past-dated instance was ever created.
+        past_records = await dao.list_by_date_range(
+            child.id,
+            start_iso,
+            (today - datetime.timedelta(days=1)).isoformat(),
+        )
+        assert past_records == []
+        return count
+
+    _with_db(tmp_path, "materialize-past-start.db")(_body)
+
+
 def test_materialize_skips_inactive_definitions(tmp_path) -> None:
     async def _body(database):
         from custom_components.nestquest.quest_definitions import (
@@ -1067,6 +1157,494 @@ def test_regenerate_for_child_is_child_scoped(tmp_path) -> None:
     _with_db(tmp_path, "regenerate-child-scoped.db")(_body)
 
 
+def test_regenerate_for_definition_respects_horizon_days(tmp_path) -> None:
+    """A non-default horizon_days sizes the definition's rebuild window."""
+    async def _body(database):
+        children = ChildrenDao(database)
+        child = await children.create("Ada", NOW)
+
+        today = datetime.date.today()
+        start_iso = today.isoformat()
+
+        created = await create_quest_definition(
+            database,
+            "Daily chore",
+            ScheduleRule(rule_type=RuleType.DAILY, start_date=start_iso),
+            [child.id],
+            [("morning", "09:00")],
+        )
+
+        # ``create`` does not materialize; regeneration over a 5-day horizon
+        # must build exactly today..today+5 (six daily rows).
+        await regenerate_for_definition(
+            database, created.definition.id, horizon_days=5
+        )
+
+        dao = QuestInstancesDao(database)
+        horizon_end = today + datetime.timedelta(days=5)
+        records = await dao.list_by_date_range(
+            child.id, start_iso, horizon_end.isoformat()
+        )
+        assert len(records) == 6
+
+        # The window is BOUNDED: nothing must exist at day 6 or later (a
+        # hard-coded 14-day default would still emit rows there).
+        beyond = (today + datetime.timedelta(days=6)).isoformat()
+        beyond_end = (
+            today + datetime.timedelta(days=DEFAULT_HORIZON_DAYS)
+        ).isoformat()
+        assert await dao.list_by_date_range(child.id, beyond, beyond_end) == []
+        return None
+
+    _with_db(tmp_path, "regenerate-def-horizon.db")(_body)
+
+
+def test_regenerate_for_child_respects_horizon_days(tmp_path) -> None:
+    """A non-default horizon_days sizes the child's rebuild window."""
+    async def _body(database):
+        children = ChildrenDao(database)
+        child = await children.create("Ada", NOW)
+
+        today = datetime.date.today()
+        start_iso = today.isoformat()
+
+        await create_quest_definition(
+            database,
+            "Daily chore",
+            ScheduleRule(rule_type=RuleType.DAILY, start_date=start_iso),
+            [child.id],
+            [("morning", "09:00")],
+        )
+
+        await regenerate_for_child(database, child.id, horizon_days=5)
+
+        dao = QuestInstancesDao(database)
+        horizon_end = today + datetime.timedelta(days=5)
+        records = await dao.list_by_date_range(
+            child.id, start_iso, horizon_end.isoformat()
+        )
+        assert len(records) == 6
+
+        # Bounded window: nothing must exist at day 6 or later.
+        beyond = (today + datetime.timedelta(days=6)).isoformat()
+        beyond_end = (
+            today + datetime.timedelta(days=DEFAULT_HORIZON_DAYS)
+        ).isoformat()
+        assert await dao.list_by_date_range(child.id, beyond, beyond_end) == []
+        return None
+
+    _with_db(tmp_path, "regenerate-child-horizon.db")(_body)
+
+
+@pytest.mark.parametrize("bad", [-1, 0, True, False, "5", 1.5])
+def test_regenerate_for_definition_rejects_invalid_horizon_before_delete(
+    tmp_path, bad
+) -> None:
+    """A malformed horizon fails BEFORE any future-instance delete."""
+    async def _body(database):
+        children = ChildrenDao(database)
+        child = await children.create("Ada", NOW)
+
+        today = datetime.date.today()
+        start_iso = today.isoformat()
+        horizon_end = today + datetime.timedelta(days=DEFAULT_HORIZON_DAYS)
+
+        created = await create_quest_definition(
+            database,
+            "Daily chore",
+            ScheduleRule(rule_type=RuleType.DAILY, start_date=start_iso),
+            [child.id],
+            [("morning", "09:00")],
+        )
+        dao = QuestInstancesDao(database)
+        await materialize(database, start_iso, horizon_end.isoformat())
+
+        with pytest.raises(ValueError, match="horizon_days"):
+            await regenerate_for_definition(
+                database, created.definition.id, horizon_days=bad
+            )
+
+        # The refused call deleted nothing: the seeded horizon survives.
+        records = await dao.list_by_date_range(
+            child.id, start_iso, horizon_end.isoformat()
+        )
+        assert len(records) == DEFAULT_HORIZON_DAYS + 1
+        return None
+
+    _with_db(tmp_path, "regenerate-def-horizon-invalid.db")(_body)
+
+
+@pytest.mark.parametrize("bad", [-1, 0, True, False, "5", 1.5])
+def test_regenerate_for_child_rejects_invalid_horizon_before_delete(
+    tmp_path, bad
+) -> None:
+    """A malformed child horizon fails BEFORE any future-instance delete."""
+    async def _body(database):
+        children = ChildrenDao(database)
+        child = await children.create("Ada", NOW)
+
+        today = datetime.date.today()
+        start_iso = today.isoformat()
+        horizon_end = today + datetime.timedelta(days=DEFAULT_HORIZON_DAYS)
+
+        await create_quest_definition(
+            database,
+            "Daily chore",
+            ScheduleRule(rule_type=RuleType.DAILY, start_date=start_iso),
+            [child.id],
+            [("morning", "09:00")],
+        )
+        dao = QuestInstancesDao(database)
+        await materialize(database, start_iso, horizon_end.isoformat())
+
+        with pytest.raises(ValueError, match="horizon_days"):
+            await regenerate_for_child(database, child.id, horizon_days=bad)
+
+        records = await dao.list_by_date_range(
+            child.id, start_iso, horizon_end.isoformat()
+        )
+        assert len(records) == DEFAULT_HORIZON_DAYS + 1
+        return None
+
+    _with_db(tmp_path, "regenerate-child-horizon-invalid.db")(_body)
+
+
+#: Fixed end-to-end anchor: 2026-06-01 is a Monday AND the 1st of its month,
+#: so the two-week custody cycle is week-aligned and the yearly rule's
+#: "1st of the anchor month" is GUARANTEED to fire inside the 28-day window
+#: (pin ``today=anchor`` throughout so the walk never clamps this fixed
+#: calendar date up to the host clock).
+_E2E_ANCHOR = "2026-06-01"
+
+#: Hand-checked oracle over 2026-06-01 .. 2026-06-28 (69 entries).  Each row
+#: is one independent (definition, child, window, due_date, due_time); the
+#: definition/child slugs are substituted with runtime ids, but the dates are
+#: literal, reviewed by hand — no recurrence/presence math is re-run here.
+#: Custody (2-week cycle anchored on the Monday): A present weeks 0 and 2,
+#: B present weeks 1 and 3, C present every day.
+_E2E_EXPECTED = [
+    # daily  [A, C]  morning 09:00, every day.  A present weeks 0, 2.
+    ("daily", "A", "morning", "2026-06-01", "09:00"),
+    ("daily", "A", "morning", "2026-06-02", "09:00"),
+    ("daily", "A", "morning", "2026-06-03", "09:00"),
+    ("daily", "A", "morning", "2026-06-04", "09:00"),
+    ("daily", "A", "morning", "2026-06-05", "09:00"),
+    ("daily", "A", "morning", "2026-06-06", "09:00"),
+    ("daily", "A", "morning", "2026-06-07", "09:00"),
+    ("daily", "A", "morning", "2026-06-15", "09:00"),
+    ("daily", "A", "morning", "2026-06-16", "09:00"),
+    ("daily", "A", "morning", "2026-06-17", "09:00"),
+    ("daily", "A", "morning", "2026-06-18", "09:00"),
+    ("daily", "A", "morning", "2026-06-19", "09:00"),
+    ("daily", "A", "morning", "2026-06-20", "09:00"),
+    ("daily", "A", "morning", "2026-06-21", "09:00"),
+    # daily  C is present every day: all 28 days.
+    ("daily", "C", "morning", "2026-06-01", "09:00"),
+    ("daily", "C", "morning", "2026-06-02", "09:00"),
+    ("daily", "C", "morning", "2026-06-03", "09:00"),
+    ("daily", "C", "morning", "2026-06-04", "09:00"),
+    ("daily", "C", "morning", "2026-06-05", "09:00"),
+    ("daily", "C", "morning", "2026-06-06", "09:00"),
+    ("daily", "C", "morning", "2026-06-07", "09:00"),
+    ("daily", "C", "morning", "2026-06-08", "09:00"),
+    ("daily", "C", "morning", "2026-06-09", "09:00"),
+    ("daily", "C", "morning", "2026-06-10", "09:00"),
+    ("daily", "C", "morning", "2026-06-11", "09:00"),
+    ("daily", "C", "morning", "2026-06-12", "09:00"),
+    ("daily", "C", "morning", "2026-06-13", "09:00"),
+    ("daily", "C", "morning", "2026-06-14", "09:00"),
+    ("daily", "C", "morning", "2026-06-15", "09:00"),
+    ("daily", "C", "morning", "2026-06-16", "09:00"),
+    ("daily", "C", "morning", "2026-06-17", "09:00"),
+    ("daily", "C", "morning", "2026-06-18", "09:00"),
+    ("daily", "C", "morning", "2026-06-19", "09:00"),
+    ("daily", "C", "morning", "2026-06-20", "09:00"),
+    ("daily", "C", "morning", "2026-06-21", "09:00"),
+    ("daily", "C", "morning", "2026-06-22", "09:00"),
+    ("daily", "C", "morning", "2026-06-23", "09:00"),
+    ("daily", "C", "morning", "2026-06-24", "09:00"),
+    ("daily", "C", "morning", "2026-06-25", "09:00"),
+    ("daily", "C", "morning", "2026-06-26", "09:00"),
+    ("daily", "C", "morning", "2026-06-27", "09:00"),
+    ("daily", "C", "morning", "2026-06-28", "09:00"),
+    # weekly  [B, C]  Mondays, morning 07:00 + evening 19:00.
+    # B present weeks 1, 3 -> Mondays 06-08 and 06-22.
+    ("weekly", "B", "morning", "2026-06-08", "07:00"),
+    ("weekly", "B", "evening", "2026-06-08", "19:00"),
+    ("weekly", "B", "morning", "2026-06-22", "07:00"),
+    ("weekly", "B", "evening", "2026-06-22", "19:00"),
+    # C present every Monday: 06-01, 06-08, 06-15, 06-22.
+    ("weekly", "C", "morning", "2026-06-01", "07:00"),
+    ("weekly", "C", "evening", "2026-06-01", "19:00"),
+    ("weekly", "C", "morning", "2026-06-08", "07:00"),
+    ("weekly", "C", "evening", "2026-06-08", "19:00"),
+    ("weekly", "C", "morning", "2026-06-15", "07:00"),
+    ("weekly", "C", "evening", "2026-06-15", "19:00"),
+    ("weekly", "C", "morning", "2026-06-22", "07:00"),
+    ("weekly", "C", "evening", "2026-06-22", "19:00"),
+    # month_day  [C]  the 15th, morning 08:00.  2026-06-15 is the 15th.
+    ("month_day", "C", "morning", "2026-06-15", "08:00"),
+    # month_wd  [C]  2nd Wednesday, morning 07:30.  June 2026's 2nd
+    # Wednesday is 06-10 (the 1st is 06-03).
+    ("month_wd", "C", "morning", "2026-06-10", "07:30"),
+    # yearly  [C]  1st of June, afternoon 12:00.  Fires on 06-01.
+    ("yearly", "C", "afternoon", "2026-06-01", "12:00"),
+    # custom  [A, C]  Saturdays + Sundays, evening 20:00.
+    # A present weeks 0, 2 -> 06-06, 06-07, 06-20, 06-21.
+    ("custom", "A", "evening", "2026-06-06", "20:00"),
+    ("custom", "A", "evening", "2026-06-07", "20:00"),
+    ("custom", "A", "evening", "2026-06-20", "20:00"),
+    ("custom", "A", "evening", "2026-06-21", "20:00"),
+    # C present every weekend day.
+    ("custom", "C", "evening", "2026-06-06", "20:00"),
+    ("custom", "C", "evening", "2026-06-07", "20:00"),
+    ("custom", "C", "evening", "2026-06-13", "20:00"),
+    ("custom", "C", "evening", "2026-06-14", "20:00"),
+    ("custom", "C", "evening", "2026-06-20", "20:00"),
+    ("custom", "C", "evening", "2026-06-21", "20:00"),
+    ("custom", "C", "evening", "2026-06-27", "20:00"),
+    ("custom", "C", "evening", "2026-06-28", "20:00"),
+]
+
+# The tuples that must disappear when Cleo (C) is overridden to ABSENT for
+# 2026-06-04 .. 2026-06-06 (a mid-window stretch): her two daily chores and
+# the Saturday-evening custom chore on 06-06.
+_E2E_REMOVED = [
+    ("daily", "C", "morning", "2026-06-04", "09:00"),
+    ("daily", "C", "morning", "2026-06-05", "09:00"),
+    ("daily", "C", "morning", "2026-06-06", "09:00"),
+    ("custom", "C", "evening", "2026-06-06", "20:00"),
+]
+
+
+def _resolve_e2e(raw, def_ids, child_ids) -> set:
+    """Substitute the oracle's definition/child slugs with runtime ids."""
+    return {
+        (def_ids[slug], child_ids[child], window, due_date, due_time)
+        for slug, child, window, due_date, due_time in raw
+    }
+
+
+async def _collect_keyed(database, child_ids, start, end) -> dict:
+    """Return {(definition_id, child_id, window, due_date): (id, due_time)}.
+
+    The stable parts of an instance — its widened key, its physical id and
+    its due_time snapshot — with the refreshable ``generated_at`` stamp
+    deliberately excluded.  Comparing two of these captures the real
+    re-run contract: no rows added/removed, ids stable (upsert refreshes
+    in place, never delete + reinsert), and due_time untouched.
+    """
+    dao = QuestInstancesDao(database)
+    keyed = {}
+    for child_id in child_ids:
+        for record in await dao.list_by_date_range(child_id, start, end):
+            key = (
+                record.definition_id,
+                record.child_id,
+                record.window,
+                record.due_date,
+            )
+            keyed[key] = (record.id, record.due_time)
+    return keyed
+
+
+async def _collect_records(database, child_ids, start, end) -> set:
+    """Return the full 7-field instance records over the children/range.
+
+    Includes the ``generated_at`` stamp, so this is only used for children
+    that should NEVER be written (Ada/Bo during Cleo's override): their
+    records are truly byte-for-byte untouched, unlike the idempotency
+    re-run where the stamp legitimately refreshes.
+    """
+    dao = QuestInstancesDao(database)
+    records = set()
+    for child_id in child_ids:
+        for record in await dao.list_by_date_range(child_id, start, end):
+            records.add(
+                (
+                    record.id,
+                    record.definition_id,
+                    record.child_id,
+                    record.window,
+                    record.due_date,
+                    record.due_time,
+                    record.generated_at,
+                )
+            )
+    return records
+
+
+def test_materialize_end_to_end_six_rule_types(tmp_path, monkeypatch) -> None:
+    import custom_components.nestquest.materialize as materialize_module
+
+    # Give each materialize run a DISTINCT batch stamp: production upserts
+    # rewrite generated_at on every re-run, so a shared pinned stamp would
+    # merely hide that rewrite.  The idempotency assertion below therefore
+    # ignores generated_at and checks the stable columns only.
+    stamps = {"n": 0}
+
+    def _distinct_stamp() -> str:
+        stamps["n"] += 1
+        return f"2026-06-01T00:00:{stamps['n']:02d}+00:00"
+
+    monkeypatch.setattr(materialize_module, "_now_stamp", _distinct_stamp)
+
+    async def _body(database):
+        from custom_components.nestquest.dao_presence import (
+            PresenceOverridesDao,
+        )
+        from custom_components.nestquest.presence import PresenceSchedule
+
+        children = ChildrenDao(database)
+        schedules = PresenceSchedulesDao(database)
+        overrides = PresenceOverridesDao(database)
+
+        a = await children.create("Ada", NOW)      # present weeks 0, 2
+        b = await children.create("Bo", NOW)       # present weeks 1, 3
+        c = await children.create("Cleo", NOW)     # no schedule: always present
+
+        anchor = datetime.date.fromisoformat(_E2E_ANCHOR)
+        start_iso = anchor.isoformat()
+        end_iso = (anchor + datetime.timedelta(days=27)).isoformat()
+
+        # Two-week custody with OPPOSITE weeks, encoded through the
+        # PresenceSchedule model on the fixed Monday anchor.
+        all_week = frozenset(range(7))
+        a_schedule = PresenceSchedule(a.id, 2, anchor, {0: all_week, 1: frozenset()})
+        b_schedule = PresenceSchedule(b.id, 2, anchor, {0: frozenset(), 1: all_week})
+        await schedules.upsert_by_child(a.id, 2, start_iso, a_schedule.encode())
+        await schedules.upsert_by_child(b.id, 2, start_iso, b_schedule.encode())
+
+        def_ids = {}
+        def_ids["daily"] = (await create_quest_definition(
+            database,
+            "Daily chore",
+            ScheduleRule(rule_type=RuleType.DAILY, start_date=start_iso),
+            [a.id, c.id],
+            [("morning", "09:00")],
+        )).definition.id
+        def_ids["weekly"] = (await create_quest_definition(
+            database,
+            "Weekly Monday chore",
+            ScheduleRule(
+                rule_type=RuleType.WEEKLY,
+                weekday_set={0},
+                start_date=start_iso,
+            ),
+            [b.id, c.id],
+            [("morning", "07:00"), ("evening", "19:00")],
+        )).definition.id
+        def_ids["month_day"] = (await create_quest_definition(
+            database,
+            "Monthly 15th chore",
+            ScheduleRule(
+                rule_type=RuleType.MONTHLY_DAY,
+                day_of_month=15,
+                start_date=start_iso,
+            ),
+            [c.id],
+            [("morning", "08:00")],
+        )).definition.id
+        def_ids["month_wd"] = (await create_quest_definition(
+            database,
+            "Monthly 2nd-Wednesday chore",
+            ScheduleRule(
+                rule_type=RuleType.MONTHLY_WEEKDAY,
+                nth_weekday=2,
+                nth_weekday_weekday=2,
+                start_date=start_iso,
+            ),
+            [c.id],
+            [("morning", "07:30")],
+        )).definition.id
+        def_ids["yearly"] = (await create_quest_definition(
+            database,
+            "Yearly first-of-June chore",
+            ScheduleRule(
+                rule_type=RuleType.YEARLY,
+                month=anchor.month,
+                day_of_month=1,
+                start_date=start_iso,
+            ),
+            [c.id],
+            [("afternoon", "12:00")],
+        )).definition.id
+        def_ids["custom"] = (await create_quest_definition(
+            database,
+            "Weekend chore",
+            ScheduleRule(
+                rule_type=RuleType.CUSTOM_DAYS,
+                weekday_set={5, 6},
+                start_date=start_iso,
+            ),
+            [a.id, c.id],
+            [("evening", "20:00")],
+        )).definition.id
+
+        child_ids = {"A": a.id, "B": b.id, "C": c.id}
+        expected = _resolve_e2e(_E2E_EXPECTED, def_ids, child_ids)
+        removed = _resolve_e2e(_E2E_REMOVED, def_ids, child_ids)
+        all_children = (a.id, b.id, c.id)
+
+        # First run: every (definition, child, window, date) tuple, exactly.
+        first = await materialize(database, start_iso, end_iso, today=anchor)
+        assert first == len(expected)
+        assert await _collect_instances(
+            database, all_children, start_iso, end_iso
+        ) == expected
+
+        # Re-run contract: the upsert refreshes each existing row IN PLACE,
+        # so the widened key set, the physical ids and each due_time are all
+        # stable (only generated_at may refresh to the new run's stamp).
+        first_keyed = await _collect_keyed(
+            database, all_children, start_iso, end_iso
+        )
+        second = await materialize(database, start_iso, end_iso, today=anchor)
+        assert second == len(expected)
+        assert await _collect_keyed(
+            database, all_children, start_iso, end_iso
+        ) == first_keyed
+
+        # Capture Ada and Bo's complete records BEFORE the override, so we
+        # can prove they are untouched afterward.
+        a_before = await _collect_records(database, (a.id,), start_iso, end_iso)
+        b_before = await _collect_records(database, (b.id,), start_iso, end_iso)
+
+        # Cleo is ABSENT 2026-06-04 .. 2026-06-06 (mid-window).
+        await overrides.create(
+            c.id, "2026-06-04", "2026-06-06", False, note="away"
+        )
+
+        # regenerate_for_child deletes + rebuilds CLEO ONLY (Ada and Bo are
+        # never touched).  It rebuilds a 14-day rolling horizon though, so
+        # the child-scoped materialize below restores the remainder of the
+        # 28-day window without ever writing another child.
+        await regenerate_for_child(database, c.id, today=anchor)
+        await materialize(
+            database, start_iso, end_iso, child_ids=[c.id], today=anchor
+        )
+
+        # Ada and Bo are byte-for-byte untouched: id, snapshot columns and
+        # generated_at alike.
+        assert await _collect_records(
+            database, (a.id,), start_iso, end_iso
+        ) == a_before
+        assert await _collect_records(
+            database, (b.id,), start_iso, end_iso
+        ) == b_before
+
+        # Exactly Cleo's override-covered tuples vanish; every other tuple
+        # survives.
+        remaining = await _collect_instances(
+            database, all_children, start_iso, end_iso
+        )
+        assert remaining == expected - removed
+        assert remaining.isdisjoint(removed)
+        return first
+
+    _with_db(tmp_path, "materialize-e2e.db")(_body)
+
+
 def test_regenerate_for_child_rejects_non_int_child_id(tmp_path) -> None:
     async def _body(database):
         for bad in (True, False, 1.0, "1"):

tests/test_quest_definitions.py

@@ -8,6 +8,7 @@ import re
 import pytest
 
 from custom_components.nestquest.dao_children import ChildrenDao
+from custom_components.nestquest.const import DEFAULT_HORIZON_DAYS
 from custom_components.nestquest.dao_instances import (
     CompletionEventsDao,
     QuestInstancesDao,
@@ -1938,3 +1939,71 @@ def test_full_lifecycle_preserves_completed_and_history(tmp_path) -> None:
         return reactivated
 
     _with_db(tmp_path, "full-lifecycle.db")(_body)
+
+
+@pytest.mark.parametrize(
+    "mode",
+    ["edit", "assign", "unassign", "set_active"],
+)
+def test_wrappers_forward_horizon_days(tmp_path, mode) -> None:
+    """The four change wrappers forward a non-default horizon_days.
+
+    Each wrapper threads ``horizon_days`` into the regeneration it triggers;
+    passing 5 here must bound the regenerated window to today..today+5 —
+    proving the forwarding argument is actually honored, not dropped.
+    """
+    async def _body(database, children, rules, definitions, child):
+        created = await create_quest_definition(
+            database,
+            "Chore",
+            ScheduleRule(rule_type=RuleType.DAILY, start_date=_today_iso()),
+            [child.id],
+            ["morning"],
+        )
+        definition_id = created.definition.id
+        instances = QuestInstancesDao(database)
+
+        if mode == "edit":
+            await edit_quest_definition(
+                database,
+                definition_id,
+                windows=[("morning", "10:30")],
+                horizon_days=5,
+            )
+            tracked = child
+        elif mode == "assign":
+            bo = await children.create("Bo", NOW)
+            await assign_child(database, definition_id, bo.id, horizon_days=5)
+            tracked = bo
+        elif mode == "unassign":
+            # The remaining assignee (``child``) must be regenerated over
+            # the 5-day window after ``bo`` is removed.
+            bo = await children.create("Bo", NOW)
+            await assign_child(database, definition_id, bo.id)
+            await unassign_child(
+                database, definition_id, bo.id, horizon_days=5
+            )
+            tracked = child
+        else:  # set_active
+            await set_quest_definition_active(
+                database, definition_id, True, horizon_days=5
+            )
+            tracked = child
+
+        today = datetime.date.today()
+        end = (today + datetime.timedelta(days=5)).isoformat()
+        records = await instances.list_by_date_range(
+            tracked.id, today.isoformat(), end
+        )
+        assert len(records) == 6
+
+        beyond = (today + datetime.timedelta(days=6)).isoformat()
+        beyond_end = (
+            today + datetime.timedelta(days=DEFAULT_HORIZON_DAYS)
+        ).isoformat()
+        assert await instances.list_by_date_range(
+            tracked.id, beyond, beyond_end
+        ) == []
+        return None
+
+    _with_db(tmp_path, f"wrapper-horizon-{mode}.db")(_body)