# Default Derivation Rules
# Reusable derivation rules for calculating derived properties from source properties.
# These can be referenced by name in derived_properties definitions.

version: "1.0"

derivations:
  # ============================================
  # BATTERY DERIVATIONS
  # ============================================

  # Battery status from percentage
  # Threshold: < 20% = low, >= 20% = ok
  battery_status_from_percentage:
    description: "Derive battery status enum from percentage value"
    rule:
      type: threshold
      thresholds:
        - max: 19
          value: "low"
        - value: "ok"

  # ============================================
  # ILLUMINANCE DERIVATIONS
  # ============================================

  # Illuminance level from lux density
  # Based on typical indoor lighting levels:
  # - dark: < 10 lux (moonlight, very dim)
  # - dusky: 10-100 lux (dim indoor lighting)
  # - moderate: 100-1000 lux (typical indoor lighting)
  # - bright: >= 1000 lux (bright indoor or daylight)
  illuminance_level_from_density:
    description: "Derive illuminance level enum from lux value"
    rule:
      type: threshold
      thresholds:
        - max: 9
          value: "dark"
        - max: 99
          value: "dusky"
        - max: 999
          value: "moderate"
        - value: "bright"

  # ============================================
  # LOCK DERIVATIONS
  # ============================================

  # Lock status from on/off state
  # on=true means locked, on=false means unlocked
  lock_status_from_on:
    description: "Derive lock status enum from on/off boolean"
    rule:
      type: boolean_map
      true_value: "locked"
      false_value: "unlocked"

  # ============================================
  # GAS SENSOR DERIVATIONS
  # ============================================

  # Gas status from detected boolean
  # detected=true means alarm, detected=false means normal
  gas_status_from_detected:
    description: "Derive gas sensor status from detected boolean"
    rule:
      type: boolean_map
      true_value: "alarm"
      false_value: "normal"

  # ============================================
  # LEAK SENSOR DERIVATIONS
  # ============================================

  # Leak level from detected boolean
  # detected=true means high, detected=false means none
  leak_level_from_detected:
    description: "Derive leak level from detected boolean"
    rule:
      type: boolean_map
      true_value: "high"
      false_value: "none"

  # ============================================
  # WINDOW COVERING DERIVATIONS
  # ============================================

  # Window covering status from position percentage
  # 0% = closed, 100% = opened, between = stopped (in partial position)
  window_covering_status_from_position:
    description: "Derive window covering status from position percentage"
    rule:
      type: position_status
      closed_value: "closed"
      opened_value: "opened"
      partial_value: "stopped"

  # ============================================
  # SULPHUR DIOXIDE DERIVATIONS
  # ============================================

  # SO2 level from density (µg/m³)
  # Based on WHO guidelines and air quality standards:
  # - good: < 20 µg/m³ (safe levels)
  # - moderate: 20-100 µg/m³ (acceptable)
  # - poor: 100-350 µg/m³ (unhealthy for sensitive groups)
  # - very_poor: >= 350 µg/m³ (unhealthy)
  sulphur_dioxide_level_from_density:
    description: "Derive SO2 air quality level from density"
    rule:
      type: threshold
      thresholds:
        - max: 19
          value: "good"
        - max: 99
          value: "moderate"
        - max: 349
          value: "poor"
        - value: "very_poor"

  # ============================================
  # AIR QUALITY INDEX DERIVATIONS
  # ============================================

  # AQI level from value
  # Based on standard AQI breakpoints:
  # - excellent: 0-50 (Good)
  # - good: 51-100 (Moderate)
  # - fair: 101-150 (Unhealthy for Sensitive Groups)
  # - inferior: 151-200 (Unhealthy)
  # - poor: 201+ (Very Unhealthy/Hazardous)
  aqi_level_from_value:
    description: "Derive air quality level from AQI value"
    rule:
      type: threshold
      thresholds:
        - max: 50
          value: "excellent"
        - max: 100
          value: "good"
        - max: 150
          value: "fair"
        - max: 200
          value: "inferior"
        - value: "poor"

  # ============================================
  # FILTER DERIVATIONS
  # ============================================

  # Filter status from life remaining percentage
  # - good: > 20% life remaining
  # - replace_soon: 5-20% life remaining
  # - replace_now: < 5% life remaining
  filter_status_from_life:
    description: "Derive filter status from life remaining percentage"
    rule:
      type: threshold
      thresholds:
        - max: 4
          value: "replace_now"
        - max: 20
          value: "replace_soon"
        - value: "good"