thermostat_id = data.get('thermostat')
heat_state = data.get('heat_state', 'heat')
idle_state = data.get('idle_state', 'off')
idle_heat_temp = data.get('idle_heat_temp', 8)

if thermostat_id:
    thermostat = hass.states.get(thermostat_id)
    attributes = thermostat.attributes.copy()
    attributes['operation_list'] = '{},{}'.format(heat_state, idle_state)
    if float(attributes['temperature']) > idle_heat_temp:
        state = heat_state
        attributes['operation_mode'] = heat_state
    else:
        state = idle_state
        attributes['operation_mode'] = idle_state
    hass.states.set(thermostat_id, state, attributes)
else:
    logger.error("Wrong arguments!")