Notification callback skipped for second listener when value is identical across listeners

[ckaysen]

When multiple entities (e.g. a binary_sensor and a switch in Home Assistant) register a notify callback for the same resource ID via add_notify_event(), only the first-registered callback receives the value change. The second (and any subsequent) listener never gets called, because _ihcvalues[ihcid] is updated inside the inner loop over callbacks, causing the equality check value != self._ihcvalues[ihcid] to be False for every listener after the first one in the same notification cycle.

Relevant code in ihccontroller.py, _notify_fn():

for ihcid, value in changes:
    if ihcid in self._ihcevents:
        for callback in self._ihcevents[ihcid]:
            if (
                ihcid not in self._ihcvalues
                or value != self._ihcvalues[ihcid]
            ):
                callback(ihcid, value)
            self._ihcvalues[ihcid] = value

Since self._ihcvalues[ihcid] = value is set inside the for callback loop, after the first callback executes, all later callbacks in the same loop see value == self._ihcvalues[ihcid] and are skipped.

Suggested fix: move self._ihcvalues[ihcid] = value outside the inner for callback loop, so the comparison happens once per resource change, not once per callback:

for ihcid, value in changes:
    if ihcid in self._ihcevents:
        if ihcid not in self._ihcvalues or value != self._ihcvalues[ihcid]:
            for callback in self._ihcevents[ihcid]:
                callback(ihcid, value)
        self._ihcvalues[ihcid] = value

Reproduction:

1. Define the same IHC resource ID both as a binary_sensor (autosetup) and as the status id for a switch (manual setup with on_id/off_id) in HA's IHC integration (haihc-betatest / version 2.0).
2. Restart Home Assistant.
3. Change the underlying IHC resource value (e.g. toggle an alarm panel physically).
4. Observe: the binary_sensor (registered first) updates correctly. The switch (registered second) never updates and stays "unknown" forever, even though debug logs confirm both listeners are correctly registered via add_notify_event().

Confirmed on:

• IHC Controller HW 6.1, Firmware 2.7.220
• Home Assistant 2026.x with haihc-betatest (IHC integration v2026.3.0)