Home Assistant Constant Lux Light Controller

constant_lux_light_controller.yaml

blueprint:
  name: "Constant Lux Light Controller"
  description: >
    Maintains a constant lux level by adjusting light brightness.
    Features:
    - Prioritized light groups (ceiling vs accent)
    - Sun-based color temperature for ceiling lights
    - Presence detection with delay
    - State restoration when returning to room
    - Smooth transitions
  domain: automation

  input:
    # Sensors
    lux_sensor:
      name: Lux Sensor
      description: "The light sensor to monitor lux levels"
      selector:
        entity:
          domain: sensor
          device_class: illuminance

    presence_sensor:
      name: Presence Sensor
      description: "Binary sensor for room presence detection"
      selector:
        entity:
          domain: binary_sensor

    # Conditions
    awake_sensor:
      name: Awake Sensor
      description: "Binary sensor that must be ON for automation to run"
      selector:
        entity:
          domain: binary_sensor

    bypass_switch:
      name: Bypass Switch
      description: "Input boolean that disables the automation when ON"
      selector:
        entity:
          domain: input_boolean

    # Light Groups
    ceiling_lights:
      name: Ceiling Lights (Primary)
      description: "Primary lights - dimmed first when too bright, brightened last when too dark. Color temperature follows sun."
      selector:
        entity:
          domain: light
          multiple: true

    accent_lights:
      name: Accent Lights (Secondary)
      description: "Secondary lights - dimmed after ceiling lights are off, brightened first when too dark. Maintains existing colors."
      selector:
        entity:
          domain: light
          multiple: true

    # Configuration
    target_lux:
      name: Target Lux Helper
      description: "Input number helper that contains the target lux level to maintain"
      selector:
        entity:
          domain: input_number

    presence_delay:
      name: Presence Off Delay
      description: "Minutes to wait after presence is lost before turning off lights"
      default: 3
      selector:
        number:
          min: 0
          max: 30
          unit_of_measurement: minutes
          mode: slider

    transition_time:
      name: Adjustment Transition Time
      description: "Transition time in seconds for brightness adjustments"
      default: 30
      selector:
        number:
          min: 0
          max: 120
          unit_of_measurement: seconds
          mode: slider

    turn_off_transition:
      name: Turn Off Transition Time
      description: "Transition time in seconds when turning off lights (no presence)"
      default: 5
      selector:
        number:
          min: 0
          max: 30
          unit_of_measurement: seconds
          mode: slider

    restore_transition:
      name: Restore Transition Time
      description: "Transition time in seconds when restoring lights on return"
      default: 2
      selector:
        number:
          min: 0
          max: 30
          unit_of_measurement: seconds
          mode: slider

    min_color_temp:
      name: Minimum Color Temperature
      description: "Color temperature at sunrise/sunset (warm)"
      default: 2000
      selector:
        color_temp:
          min_mireds: 153
          max_mireds: 500
          unit: kelvin

    max_color_temp:
      name: Maximum Color Temperature
      description: "Color temperature at solar noon (cool)"
      default: 6500
      selector:
        color_temp:
          min_mireds: 153
          max_mireds: 500
          unit: kelvin

    scene_name:
      name: Snapshot Scene Name
      description: "Unique name for the scene used to save/restore light states (no spaces, use underscores)"
      default: "lux_controller_snapshot"
      selector:
        text:

mode: single

trigger:
  - platform: time_pattern
    minutes: "/1"
    id: "time_trigger"
  - platform: state
    entity_id: !input presence_sensor
    from: "off"
    to: "on"
    id: "presence_restored"

condition:
  - condition: state
    entity_id: !input awake_sensor
    state: "on"
  - condition: state
    entity_id: !input bypass_switch
    state: "off"

action:
  - variables:
      # Input references - define these first
      lux_sensor_entity: !input lux_sensor
      target_lux_entity: !input target_lux
      ceiling_light_entities: !input ceiling_lights
      accent_light_entities: !input accent_lights
      presence_delay_minutes: !input presence_delay
      transition_seconds: !input transition_time
      turn_off_transition_seconds: !input turn_off_transition
      restore_transition_seconds: !input restore_transition
      min_color_temp_kelvin: !input min_color_temp
      max_color_temp_kelvin: !input max_color_temp
      snapshot_scene_id: !input scene_name

      # Derived variables
      all_light_entities: "{{ ceiling_light_entities + accent_light_entities }}"
      snapshot_scene_entity: "scene.{{ snapshot_scene_id }}"
      target_lux_value: "{{ states(target_lux_entity) | float(60) }}"

      # Check if snapshot scene exists (means we need to restore, not do lux management)
      scene_exists: "{{ states(snapshot_scene_entity) not in ['unknown', 'unavailable'] }}"

  - choose:
      # ========== PRESENCE RESTORED - Restore previous light states ==========
      - conditions:
          - condition: trigger
            id: "presence_restored"
          - condition: template
            value_template: "{{ scene_exists }}"
        sequence:
          # Restore the scene
          - service: scene.turn_on
            target:
              entity_id: "{{ snapshot_scene_entity }}"
            data:
              transition: "{{ restore_transition_seconds }}"
          # Delete the scene so lux management can resume
          - delay:
              seconds: "{{ restore_transition_seconds + 2 }}"
          - service: scene.delete
            data:
              entity_id: "{{ snapshot_scene_entity }}"

      # ========== NO PRESENCE - Save state then turn off ==========
      - conditions:
          - condition: state
            entity_id: !input presence_sensor
            state: "off"
            for:
              minutes: "{{ presence_delay_minutes }}"
          - condition: template
            value_template: "{{ not scene_exists }}"  # <-- ADD THIS LINE
        sequence:
          # Save current light states before turning off
          - service: scene.create
            data:
              scene_id: "{{ snapshot_scene_id }}"
              snapshot_entities: "{{ all_light_entities }}"
          - delay:
              seconds: 2
          # Then turn off all lights
          - service: light.turn_off
            target:
              entity_id: "{{ all_light_entities }}"
            data:
              transition: "{{ turn_off_transition_seconds }}"

      # ========== PRESENCE DETECTED - Manage lux (only if no pending restore) ==========
      - conditions:
          - condition: state
            entity_id: !input presence_sensor
            state: "on"
          - condition: template
            value_template: "{{ not scene_exists }}"
        sequence:
          - variables:
              current_lux: "{{ states(lux_sensor_entity) | float(0) }}"
              lux_diff: "{{ current_lux - target_lux_value }}"

              # Calculate sun-based color temperature
              sun_elevation: "{{ state_attr('sun.sun', 'elevation') | float(0) }}"
              color_temp_range: "{{ max_color_temp_kelvin - min_color_temp_kelvin }}"
              sun_color_temp_kelvin: >-
                {% if sun_elevation <= 0 %}
                  {{ min_color_temp_kelvin }}
                {% elif sun_elevation >= 90 %}
                  {{ max_color_temp_kelvin }}
                {% else %}
                  {{ (min_color_temp_kelvin + (sun_elevation / 90) * color_temp_range) | int }}
                {% endif %}

              # Get brightness of each ceiling light
              ceiling_brightnesses: >-
                {% set ns = namespace(brightnesses=[]) %}
                {% for light in ceiling_light_entities %}
                  {% set brightness = state_attr(light, 'brightness') | int(0) if is_state(light, 'on') else 0 %}
                  {% set ns.brightnesses = ns.brightnesses + [{'entity': light, 'brightness': brightness}] %}
                {% endfor %}
                {{ ns.brightnesses }}

              # Get brightness of each accent light
              accent_brightnesses: >-
                {% set ns = namespace(brightnesses=[]) %}
                {% for light in accent_light_entities %}
                  {% set brightness = state_attr(light, 'brightness') | int(0) if is_state(light, 'on') else 0 %}
                  {% set ns.brightnesses = ns.brightnesses + [{'entity': light, 'brightness': brightness}] %}
                {% endfor %}
                {{ ns.brightnesses }}

              # Check if any lights are on
              any_ceiling_on: "{{ ceiling_brightnesses | selectattr('brightness', 'gt', 0) | list | count > 0 }}"
              any_accent_on: "{{ accent_brightnesses | selectattr('brightness', 'gt', 0) | list | count > 0 }}"

              # Check if all lights at max
              all_accent_at_max: "{{ accent_brightnesses | selectattr('brightness', 'lt', 255) | list | count == 0 and accent_brightnesses | length > 0 }}"
              all_ceiling_at_max: "{{ ceiling_brightnesses | selectattr('brightness', 'lt', 255) | list | count == 0 and ceiling_brightnesses | length > 0 }}"

              # Find brightest ceiling light (for dimming)
              brightest_ceiling: >-
                {% set sorted = ceiling_brightnesses | sort(attribute='brightness', reverse=true) %}
                {% if sorted | length > 0 and sorted[0].brightness > 0 %}
                  {{ sorted[0] }}
                {% else %}
                  {{ {'entity': 'none', 'brightness': 0} }}
                {% endif %}

              # Find dimmest ceiling light (for brightening)
              dimmest_ceiling: >-
                {% set sorted = ceiling_brightnesses | sort(attribute='brightness') %}
                {% if sorted | length > 0 and sorted[0].brightness < 255 %}
                  {{ sorted[0] }}
                {% else %}
                  {{ {'entity': 'none', 'brightness': 255} }}
                {% endif %}

              # Find brightest accent light (for dimming)
              brightest_accent: >-
                {% set sorted = accent_brightnesses | sort(attribute='brightness', reverse=true) %}
                {% if sorted | length > 0 and sorted[0].brightness > 0 %}
                  {{ sorted[0] }}
                {% else %}
                  {{ {'entity': 'none', 'brightness': 0} }}
                {% endif %}

              # Find dimmest accent light (for brightening)
              dimmest_accent: >-
                {% set sorted = accent_brightnesses | sort(attribute='brightness') %}
                {% if sorted | length > 0 and sorted[0].brightness < 255 %}
                  {{ sorted[0] }}
                {% else %}
                  {{ {'entity': 'none', 'brightness': 255} }}
                {% endif %}

              # Calculate brightness step
              brightness_step: "{{ [1, (lux_diff | abs / 2) | int] | max }}"

          - choose:
              # ========== TOO BRIGHT - REDUCE LIGHTS ==========
              - conditions:
                  - condition: template
                    value_template: "{{ lux_diff > 0 }}"
                sequence:
                  - choose:
                      # First: Reduce ceiling lights if any are on
                      - conditions:
                          - condition: template
                            value_template: "{{ any_ceiling_on and brightest_ceiling.entity != 'none' }}"
                        sequence:
                          - variables:
                              new_brightness: "{{ [0, brightest_ceiling.brightness - brightness_step] | max }}"
                          - choose:
                              - conditions:
                                  - condition: template
                                    value_template: "{{ new_brightness <= 0 }}"
                                sequence:
                                  - service: light.turn_off
                                    target:
                                      entity_id: "{{ brightest_ceiling.entity }}"
                                    data:
                                      transition: "{{ transition_seconds }}"
                            default:
                              - service: light.turn_on
                                target:
                                  entity_id: "{{ brightest_ceiling.entity }}"
                                data:
                                  brightness: "{{ new_brightness }}"
                                  color_temp_kelvin: "{{ sun_color_temp_kelvin }}"
                                  transition: "{{ transition_seconds }}"

                      # Second: If all ceiling lights are off, reduce accent lights
                      - conditions:
                          - condition: template
                            value_template: "{{ not any_ceiling_on and brightest_accent.entity != 'none' }}"
                        sequence:
                          - variables:
                              new_brightness: "{{ [0, brightest_accent.brightness - brightness_step] | max }}"
                          - choose:
                              - conditions:
                                  - condition: template
                                    value_template: "{{ new_brightness <= 0 }}"
                                sequence:
                                  - service: light.turn_off
                                    target:
                                      entity_id: "{{ brightest_accent.entity }}"
                                    data:
                                      transition: "{{ transition_seconds }}"
                            default:
                              - service: light.turn_on
                                target:
                                  entity_id: "{{ brightest_accent.entity }}"
                                data:
                                  brightness: "{{ new_brightness }}"
                                  transition: "{{ transition_seconds }}"

              # ========== TOO DARK - INCREASE LIGHTS ==========
              - conditions:
                  - condition: template
                    value_template: "{{ lux_diff < 0 }}"
                sequence:
                  - choose:
                      # First: Increase accent lights (if not all at max)
                      - conditions:
                          - condition: template
                            value_template: "{{ not all_accent_at_max and dimmest_accent.entity != 'none' }}"
                        sequence:
                          - variables:
                              new_brightness: "{{ [255, dimmest_accent.brightness + brightness_step] | min }}"
                          - choose:
                              - conditions:
                                  - condition: template
                                    value_template: "{{ dimmest_accent.brightness == 0 }}"
                                sequence:
                                  - service: light.turn_on
                                    target:
                                      entity_id: "{{ dimmest_accent.entity }}"
                                    data:
                                      brightness: "{{ brightness_step }}"
                                      transition: "{{ transition_seconds }}"
                            default:
                              - service: light.turn_on
                                target:
                                  entity_id: "{{ dimmest_accent.entity }}"
                                data:
                                  brightness: "{{ new_brightness }}"
                                  transition: "{{ transition_seconds }}"

                      # Second: If all accent lights at max, increase ceiling lights
                      - conditions:
                          - condition: template
                            value_template: "{{ all_accent_at_max and dimmest_ceiling.entity != 'none' }}"
                        sequence:
                          - variables:
                              new_brightness: "{{ [255, dimmest_ceiling.brightness + brightness_step] | min }}"
                          - choose:
                              - conditions:
                                  - condition: template
                                    value_template: "{{ dimmest_ceiling.brightness == 0 }}"
                                sequence:
                                  - service: light.turn_on
                                    target:
                                      entity_id: "{{ dimmest_ceiling.entity }}"
                                    data:
                                      brightness: "{{ brightness_step }}"
                                      color_temp_kelvin: "{{ sun_color_temp_kelvin }}"
                                      transition: "{{ transition_seconds }}"
                            default:
                              - service: light.turn_on
                                target:
                                  entity_id: "{{ dimmest_ceiling.entity }}"
                                data:
                                  brightness: "{{ new_brightness }}"
                                  color_temp_kelvin: "{{ sun_color_temp_kelvin }}"
                                  transition: "{{ transition_seconds }}"