Allow clearing optional weather sources in Options

Optional weather source fields used the current selection as the form
default. A cleared field that the frontend omits was refilled with the
old sources by voluptuous, and an options key missing from the
submission fell back to the original setup data. Optional providers
could therefore not be removed in the UI.

Pre-fill with suggested values instead, and save omitted optional lists
as empty so they override older entry data. No UI strings changed.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

custom_components/heating_mpc/config_flow.py

@@ -63,11 +63,21 @@ def _weather_schema(config: dict[str, Any], metrics: tuple[str, ...]):
             # A temperature source is mandatory: other weather inputs are optional.
             marker = vol.Required(key, default=selected) if selected else vol.Required(key)
         else:
-            marker = vol.Optional(key, default=selected)
+            # A default would re-insert old sources whenever a cleared field is
+            # omitted from the submission; a suggested value only pre-fills the form.
+            marker = vol.Optional(key, description={"suggested_value": selected})
         schema[marker] = _entity_picker(multiple=True)
     return vol.Schema(schema)
 
 
+def _with_cleared_weather(user_input: dict[str, Any], metrics: tuple[str, ...]) -> dict[str, Any]:
+    """Store an omitted optional source list as empty, so it overrides older data."""
+    result = dict(user_input)
+    for metric in metrics:
+        result.setdefault(WEATHER_SOURCES[metric], [])
+    return result
+
+
 def _weight_schema(rooms: list[str], existing: dict[str, float] | None = None):
     weights = existing or {}
     return vol.Schema({
@@ -110,14 +120,14 @@ class HeatingMPCConfigFlow(config_entries.ConfigFlow, domain=DOMAIN):
             if not _valid_weather(self._draft[CONF_ROOMS], user_input):
                 return self.async_show_form(step_id="weather", data_schema=_weather_schema(
                     user_input, WEATHER_MAIN), errors={"base": "invalid_weather"})
-            self._draft.update(user_input)
+            self._draft.update(_with_cleared_weather(user_input, WEATHER_MAIN))
             return await self.async_step_weather_extra()
         return self.async_show_form(step_id="weather", data_schema=_weather_schema(
             self._draft, WEATHER_MAIN))
 
     async def async_step_weather_extra(self, user_input: dict[str, Any] | None = None):
         if user_input is not None:
-            self._draft.update(user_input)
+            self._draft.update(_with_cleared_weather(user_input, WEATHER_EXTRA))
             return await self.async_step_weights()
         return self.async_show_form(step_id="weather_extra", data_schema=_weather_schema(
             self._draft, WEATHER_EXTRA))
@@ -161,7 +171,7 @@ class HeatingMPCOptionsFlow(config_entries.OptionsFlow):
             if not _valid_weather(self._draft[CONF_ROOMS], user_input):
                 return self.async_show_form(step_id="weather", data_schema=_weather_schema(
                     user_input, WEATHER_MAIN), errors={"base": "invalid_weather"})
-            self._draft.update(user_input)
+            self._draft.update(_with_cleared_weather(user_input, WEATHER_MAIN))
             return await self.async_step_weather_extra()
         return self.async_show_form(step_id="weather", data_schema=_weather_schema(
             config, WEATHER_MAIN))
@@ -169,7 +179,7 @@ class HeatingMPCOptionsFlow(config_entries.OptionsFlow):
     async def async_step_weather_extra(self, user_input: dict[str, Any] | None = None):
         config = {**self.config_entry.data, **self.config_entry.options, **self._draft}
         if user_input is not None:
-            self._draft.update(user_input)
+            self._draft.update(_with_cleared_weather(user_input, WEATHER_EXTRA))
             return await self.async_step_weights()
         return self.async_show_form(step_id="weather_extra", data_schema=_weather_schema(
             config, WEATHER_EXTRA))