Bidirection switch and light/group sync

Bidirection switch and light sync.yaml

blueprint:
  name: Sync Switch or Light with Target (Bi-directional)
  description: >
    Keeps a switch or light (controller) in sync with another light or switch (target),
    which can be a group or a single entity. Toggling either will toggle the other.
    Prevents feedback loops using state checks.

  domain: automation
  input:
    controller:
      name: Controller
      description: A switch or light that toggles the target (e.g. wall switch)
      selector:
        entity:
          domain:
            - switch
            - light
    target:
      name: Target
      description: A light, switch, or group that should stay in sync with the controller
      selector:
        entity:
          domain:
            - switch
            - light

trigger:
  - platform: state
    entity_id: !input controller
    to:
      - "on"
      - "off"
  - platform: state
    entity_id: !input target
    to:
      - "on"
      - "off"

variables:
  controller_entity: !input controller
  target_entity: !input target
  controller_state: "{{ states(controller_entity) }}"
  target_state: "{{ states(target_entity) }}"

mode: queued

action:
  - choose:
      # Controller changed → mirror to target if states differ
      - conditions:
          - condition: template
            value_template: "{{ trigger.entity_id == controller_entity }}"
          - condition: template
            value_template: "{{ controller_state != target_state }}"
        sequence:
          - service: >
              {% if controller_state == 'on' %}
                homeassistant.turn_on
              {% else %}
                homeassistant.turn_off
              {% endif %}
            target:
              entity_id: !input target

      # Target changed → mirror to controller if states differ
      - conditions:
          - condition: template
            value_template: "{{ trigger.entity_id == target_entity }}"
          - condition: template
            value_template: "{{ target_state != controller_state }}"
        sequence:
          - service: >
              {% if target_state == 'on' %}
                homeassistant.turn_on
              {% else %}
                homeassistant.turn_off
              {% endif %}
            target:
              entity_id: !input controller